1169689Skan/* Analyze RTL for GNU compiler. 290075Sobrien Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 3169689Skan 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006 Free Software 4169689Skan Foundation, Inc. 518334Speter 690075SobrienThis file is part of GCC. 718334Speter 890075SobrienGCC is free software; you can redistribute it and/or modify it under 990075Sobrienthe terms of the GNU General Public License as published by the Free 1090075SobrienSoftware Foundation; either version 2, or (at your option) any later 1190075Sobrienversion. 1218334Speter 1390075SobrienGCC is distributed in the hope that it will be useful, but WITHOUT ANY 1490075SobrienWARRANTY; without even the implied warranty of MERCHANTABILITY or 1590075SobrienFITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 1690075Sobrienfor more details. 1718334Speter 1818334SpeterYou should have received a copy of the GNU General Public License 1990075Sobrienalong with GCC; see the file COPYING. If not, write to the Free 20169689SkanSoftware Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 21169689Skan02110-1301, USA. */ 2218334Speter 2318334Speter 2418334Speter#include "config.h" 2550397Sobrien#include "system.h" 26132718Skan#include "coretypes.h" 27132718Skan#include "tm.h" 2890075Sobrien#include "toplev.h" 2918334Speter#include "rtl.h" 3090075Sobrien#include "hard-reg-set.h" 31117395Skan#include "insn-config.h" 32117395Skan#include "recog.h" 33169689Skan#include "target.h" 34169689Skan#include "output.h" 3590075Sobrien#include "tm_p.h" 36117395Skan#include "flags.h" 37117395Skan#include "real.h" 38169689Skan#include "regs.h" 39169689Skan#include "function.h" 4018334Speter 4150397Sobrien/* Forward declarations */ 42132718Skanstatic void set_of_1 (rtx, rtx, void *); 43169689Skanstatic bool covers_regno_p (rtx, unsigned int); 44169689Skanstatic bool covers_regno_no_parallel_p (rtx, unsigned int); 45132718Skanstatic int rtx_referenced_p_1 (rtx *, void *); 46132718Skanstatic int computed_jump_p_1 (rtx); 47132718Skanstatic void parms_set (rtx, rtx, void *); 4850397Sobrien 49169689Skanstatic unsigned HOST_WIDE_INT cached_nonzero_bits (rtx, enum machine_mode, 50169689Skan rtx, enum machine_mode, 51169689Skan unsigned HOST_WIDE_INT); 52169689Skanstatic unsigned HOST_WIDE_INT nonzero_bits1 (rtx, enum machine_mode, rtx, 53169689Skan enum machine_mode, 54169689Skan unsigned HOST_WIDE_INT); 55169689Skanstatic unsigned int cached_num_sign_bit_copies (rtx, enum machine_mode, rtx, 56169689Skan enum machine_mode, 57169689Skan unsigned int); 58169689Skanstatic unsigned int num_sign_bit_copies1 (rtx, enum machine_mode, rtx, 59169689Skan enum machine_mode, unsigned int); 60169689Skan 61169689Skan/* Offset of the first 'e', 'E' or 'V' operand for each rtx code, or 62169689Skan -1 if a code has no such operand. */ 63169689Skanstatic int non_rtx_starting_operands[NUM_RTX_CODE]; 64169689Skan 6518334Speter/* Bit flags that specify the machine subtype we are compiling for. 6618334Speter Bits are tested using macros TARGET_... defined in the tm.h file 6718334Speter and set by `-m...' switches. Must be defined in rtlanal.c. */ 6818334Speter 6918334Speterint target_flags; 70169689Skan 71169689Skan/* Truncation narrows the mode from SOURCE mode to DESTINATION mode. 72169689Skan If TARGET_MODE_REP_EXTENDED (DESTINATION, DESTINATION_REP) is 73169689Skan SIGN_EXTEND then while narrowing we also have to enforce the 74169689Skan representation and sign-extend the value to mode DESTINATION_REP. 75169689Skan 76169689Skan If the value is already sign-extended to DESTINATION_REP mode we 77169689Skan can just switch to DESTINATION mode on it. For each pair of 78169689Skan integral modes SOURCE and DESTINATION, when truncating from SOURCE 79169689Skan to DESTINATION, NUM_SIGN_BIT_COPIES_IN_REP[SOURCE][DESTINATION] 80169689Skan contains the number of high-order bits in SOURCE that have to be 81169689Skan copies of the sign-bit so that we can do this mode-switch to 82169689Skan DESTINATION. */ 83169689Skan 84169689Skanstatic unsigned int 85169689Skannum_sign_bit_copies_in_rep[MAX_MODE_INT + 1][MAX_MODE_INT + 1]; 8618334Speter 8718334Speter/* Return 1 if the value of X is unstable 8818334Speter (would be different at a different point in the program). 8918334Speter The frame pointer, arg pointer, etc. are considered stable 9018334Speter (within one function) and so is anything marked `unchanging'. */ 9118334Speter 9218334Speterint 93132718Skanrtx_unstable_p (rtx x) 9418334Speter{ 9590075Sobrien RTX_CODE code = GET_CODE (x); 9690075Sobrien int i; 9790075Sobrien const char *fmt; 9818334Speter 9990075Sobrien switch (code) 10090075Sobrien { 10190075Sobrien case MEM: 102169689Skan return !MEM_READONLY_P (x) || rtx_unstable_p (XEXP (x, 0)); 10318334Speter 10490075Sobrien case CONST: 10590075Sobrien case CONST_INT: 10690075Sobrien case CONST_DOUBLE: 10796263Sobrien case CONST_VECTOR: 10890075Sobrien case SYMBOL_REF: 10990075Sobrien case LABEL_REF: 11090075Sobrien return 0; 11118334Speter 11290075Sobrien case REG: 11390075Sobrien /* As in rtx_varies_p, we have to use the actual rtx, not reg number. */ 11490075Sobrien if (x == frame_pointer_rtx || x == hard_frame_pointer_rtx 11590075Sobrien /* The arg pointer varies if it is not a fixed register. */ 116169689Skan || (x == arg_pointer_rtx && fixed_regs[ARG_POINTER_REGNUM])) 11790075Sobrien return 0; 11890075Sobrien#ifndef PIC_OFFSET_TABLE_REG_CALL_CLOBBERED 11990075Sobrien /* ??? When call-clobbered, the value is stable modulo the restore 12090075Sobrien that must happen after a call. This currently screws up local-alloc 12190075Sobrien into believing that the restore is not needed. */ 12290075Sobrien if (x == pic_offset_table_rtx) 12390075Sobrien return 0; 12490075Sobrien#endif 12590075Sobrien return 1; 12618334Speter 12790075Sobrien case ASM_OPERANDS: 12890075Sobrien if (MEM_VOLATILE_P (x)) 12990075Sobrien return 1; 13090075Sobrien 131132718Skan /* Fall through. */ 13290075Sobrien 13390075Sobrien default: 13490075Sobrien break; 13590075Sobrien } 13690075Sobrien 13718334Speter fmt = GET_RTX_FORMAT (code); 13818334Speter for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) 13918334Speter if (fmt[i] == 'e') 14090075Sobrien { 14190075Sobrien if (rtx_unstable_p (XEXP (x, i))) 14290075Sobrien return 1; 14390075Sobrien } 14490075Sobrien else if (fmt[i] == 'E') 14590075Sobrien { 14690075Sobrien int j; 14790075Sobrien for (j = 0; j < XVECLEN (x, i); j++) 14890075Sobrien if (rtx_unstable_p (XVECEXP (x, i, j))) 14990075Sobrien return 1; 15090075Sobrien } 15190075Sobrien 15218334Speter return 0; 15318334Speter} 15418334Speter 15518334Speter/* Return 1 if X has a value that can vary even between two 15618334Speter executions of the program. 0 means X can be compared reliably 15718334Speter against certain constants or near-constants. 15890075Sobrien FOR_ALIAS is nonzero if we are called from alias analysis; if it is 15990075Sobrien zero, we are slightly more conservative. 16018334Speter The frame pointer and the arg pointer are considered constant. */ 16118334Speter 16218334Speterint 163132718Skanrtx_varies_p (rtx x, int for_alias) 16418334Speter{ 165132718Skan RTX_CODE code; 16690075Sobrien int i; 16790075Sobrien const char *fmt; 16818334Speter 169132718Skan if (!x) 170132718Skan return 0; 171132718Skan 172132718Skan code = GET_CODE (x); 17318334Speter switch (code) 17418334Speter { 17518334Speter case MEM: 176169689Skan return !MEM_READONLY_P (x) || rtx_varies_p (XEXP (x, 0), for_alias); 17790075Sobrien 17818334Speter case CONST: 17918334Speter case CONST_INT: 18018334Speter case CONST_DOUBLE: 18196263Sobrien case CONST_VECTOR: 18218334Speter case SYMBOL_REF: 18318334Speter case LABEL_REF: 18418334Speter return 0; 18518334Speter 18618334Speter case REG: 18718334Speter /* Note that we have to test for the actual rtx used for the frame 18818334Speter and arg pointers and not just the register number in case we have 18918334Speter eliminated the frame and/or arg pointer and are using it 19018334Speter for pseudos. */ 19190075Sobrien if (x == frame_pointer_rtx || x == hard_frame_pointer_rtx 19290075Sobrien /* The arg pointer varies if it is not a fixed register. */ 19390075Sobrien || (x == arg_pointer_rtx && fixed_regs[ARG_POINTER_REGNUM])) 19490075Sobrien return 0; 19590075Sobrien if (x == pic_offset_table_rtx 19690075Sobrien#ifdef PIC_OFFSET_TABLE_REG_CALL_CLOBBERED 19790075Sobrien /* ??? When call-clobbered, the value is stable modulo the restore 19890075Sobrien that must happen after a call. This currently screws up 19990075Sobrien local-alloc into believing that the restore is not needed, so we 20090075Sobrien must return 0 only if we are called from alias analysis. */ 20190075Sobrien && for_alias 20290075Sobrien#endif 20390075Sobrien ) 20490075Sobrien return 0; 20590075Sobrien return 1; 20618334Speter 20718334Speter case LO_SUM: 20818334Speter /* The operand 0 of a LO_SUM is considered constant 20990075Sobrien (in fact it is related specifically to operand 1) 21090075Sobrien during alias analysis. */ 21190075Sobrien return (! for_alias && rtx_varies_p (XEXP (x, 0), for_alias)) 21290075Sobrien || rtx_varies_p (XEXP (x, 1), for_alias); 213117395Skan 21490075Sobrien case ASM_OPERANDS: 21590075Sobrien if (MEM_VOLATILE_P (x)) 21690075Sobrien return 1; 21790075Sobrien 218132718Skan /* Fall through. */ 21990075Sobrien 22050397Sobrien default: 22150397Sobrien break; 22218334Speter } 22318334Speter 22418334Speter fmt = GET_RTX_FORMAT (code); 22518334Speter for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) 22618334Speter if (fmt[i] == 'e') 22790075Sobrien { 22890075Sobrien if (rtx_varies_p (XEXP (x, i), for_alias)) 22990075Sobrien return 1; 23090075Sobrien } 23190075Sobrien else if (fmt[i] == 'E') 23290075Sobrien { 23390075Sobrien int j; 23490075Sobrien for (j = 0; j < XVECLEN (x, i); j++) 23590075Sobrien if (rtx_varies_p (XVECEXP (x, i, j), for_alias)) 23690075Sobrien return 1; 23790075Sobrien } 23890075Sobrien 23918334Speter return 0; 24018334Speter} 24118334Speter 242169689Skan/* Return nonzero if the use of X as an address in a MEM can cause a trap. 243169689Skan MODE is the mode of the MEM (not that of X) and UNALIGNED_MEMS controls 244169689Skan whether nonzero is returned for unaligned memory accesses on strict 245169689Skan alignment machines. */ 24618334Speter 247169689Skanstatic int 248169689Skanrtx_addr_can_trap_p_1 (rtx x, enum machine_mode mode, bool unaligned_mems) 24918334Speter{ 25090075Sobrien enum rtx_code code = GET_CODE (x); 25118334Speter 25218334Speter switch (code) 25318334Speter { 25418334Speter case SYMBOL_REF: 25590075Sobrien return SYMBOL_REF_WEAK (x); 25690075Sobrien 25718334Speter case LABEL_REF: 25818334Speter return 0; 25918334Speter 26018334Speter case REG: 26118334Speter /* As in rtx_varies_p, we have to use the actual rtx, not reg number. */ 26290075Sobrien if (x == frame_pointer_rtx || x == hard_frame_pointer_rtx 26390075Sobrien || x == stack_pointer_rtx 26490075Sobrien /* The arg pointer varies if it is not a fixed register. */ 26590075Sobrien || (x == arg_pointer_rtx && fixed_regs[ARG_POINTER_REGNUM])) 26690075Sobrien return 0; 26790075Sobrien /* All of the virtual frame registers are stack references. */ 26890075Sobrien if (REGNO (x) >= FIRST_VIRTUAL_REGISTER 26990075Sobrien && REGNO (x) <= LAST_VIRTUAL_REGISTER) 27090075Sobrien return 0; 27190075Sobrien return 1; 27218334Speter 27318334Speter case CONST: 274169689Skan return rtx_addr_can_trap_p_1 (XEXP (x, 0), mode, unaligned_mems); 27518334Speter 27618334Speter case PLUS: 277169689Skan /* An address is assumed not to trap if: 278169689Skan - it is an address that can't trap plus a constant integer, 279169689Skan with the proper remainder modulo the mode size if we are 280169689Skan considering unaligned memory references. */ 281169689Skan if (!rtx_addr_can_trap_p_1 (XEXP (x, 0), mode, unaligned_mems) 282169689Skan && GET_CODE (XEXP (x, 1)) == CONST_INT) 283169689Skan { 284169689Skan HOST_WIDE_INT offset; 28518334Speter 286169689Skan if (!STRICT_ALIGNMENT 287169689Skan || !unaligned_mems 288169689Skan || GET_MODE_SIZE (mode) == 0) 289169689Skan return 0; 290169689Skan 291169689Skan offset = INTVAL (XEXP (x, 1)); 292169689Skan 293169689Skan#ifdef SPARC_STACK_BOUNDARY_HACK 294169689Skan /* ??? The SPARC port may claim a STACK_BOUNDARY higher than 295169689Skan the real alignment of %sp. However, when it does this, the 296169689Skan alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */ 297169689Skan if (SPARC_STACK_BOUNDARY_HACK 298169689Skan && (XEXP (x, 0) == stack_pointer_rtx 299169689Skan || XEXP (x, 0) == hard_frame_pointer_rtx)) 300169689Skan offset -= STACK_POINTER_OFFSET; 301169689Skan#endif 302169689Skan 303169689Skan return offset % GET_MODE_SIZE (mode) != 0; 304169689Skan } 305169689Skan 306169689Skan /* - or it is the pic register plus a constant. */ 307169689Skan if (XEXP (x, 0) == pic_offset_table_rtx && CONSTANT_P (XEXP (x, 1))) 308169689Skan return 0; 309169689Skan 310169689Skan return 1; 311169689Skan 31218334Speter case LO_SUM: 31390075Sobrien case PRE_MODIFY: 314169689Skan return rtx_addr_can_trap_p_1 (XEXP (x, 1), mode, unaligned_mems); 31590075Sobrien 31690075Sobrien case PRE_DEC: 31790075Sobrien case PRE_INC: 31890075Sobrien case POST_DEC: 31990075Sobrien case POST_INC: 32090075Sobrien case POST_MODIFY: 321169689Skan return rtx_addr_can_trap_p_1 (XEXP (x, 0), mode, unaligned_mems); 32290075Sobrien 32350397Sobrien default: 32450397Sobrien break; 32518334Speter } 32618334Speter 32718334Speter /* If it isn't one of the case above, it can cause a trap. */ 32818334Speter return 1; 32918334Speter} 33018334Speter 331169689Skan/* Return nonzero if the use of X as an address in a MEM can cause a trap. */ 332169689Skan 333169689Skanint 334169689Skanrtx_addr_can_trap_p (rtx x) 335169689Skan{ 336169689Skan return rtx_addr_can_trap_p_1 (x, VOIDmode, false); 337169689Skan} 338169689Skan 339132718Skan/* Return true if X is an address that is known to not be zero. */ 340132718Skan 341132718Skanbool 342132718Skannonzero_address_p (rtx x) 343132718Skan{ 344132718Skan enum rtx_code code = GET_CODE (x); 345132718Skan 346132718Skan switch (code) 347132718Skan { 348132718Skan case SYMBOL_REF: 349132718Skan return !SYMBOL_REF_WEAK (x); 350132718Skan 351132718Skan case LABEL_REF: 352132718Skan return true; 353132718Skan 354132718Skan case REG: 355132718Skan /* As in rtx_varies_p, we have to use the actual rtx, not reg number. */ 356132718Skan if (x == frame_pointer_rtx || x == hard_frame_pointer_rtx 357132718Skan || x == stack_pointer_rtx 358132718Skan || (x == arg_pointer_rtx && fixed_regs[ARG_POINTER_REGNUM])) 359132718Skan return true; 360132718Skan /* All of the virtual frame registers are stack references. */ 361132718Skan if (REGNO (x) >= FIRST_VIRTUAL_REGISTER 362132718Skan && REGNO (x) <= LAST_VIRTUAL_REGISTER) 363132718Skan return true; 364132718Skan return false; 365132718Skan 366132718Skan case CONST: 367132718Skan return nonzero_address_p (XEXP (x, 0)); 368132718Skan 369132718Skan case PLUS: 370132718Skan if (GET_CODE (XEXP (x, 1)) == CONST_INT) 371169689Skan return nonzero_address_p (XEXP (x, 0)); 372132718Skan /* Handle PIC references. */ 373132718Skan else if (XEXP (x, 0) == pic_offset_table_rtx 374132718Skan && CONSTANT_P (XEXP (x, 1))) 375132718Skan return true; 376132718Skan return false; 377132718Skan 378132718Skan case PRE_MODIFY: 379132718Skan /* Similar to the above; allow positive offsets. Further, since 380132718Skan auto-inc is only allowed in memories, the register must be a 381132718Skan pointer. */ 382132718Skan if (GET_CODE (XEXP (x, 1)) == CONST_INT 383132718Skan && INTVAL (XEXP (x, 1)) > 0) 384132718Skan return true; 385132718Skan return nonzero_address_p (XEXP (x, 0)); 386132718Skan 387132718Skan case PRE_INC: 388132718Skan /* Similarly. Further, the offset is always positive. */ 389132718Skan return true; 390132718Skan 391132718Skan case PRE_DEC: 392132718Skan case POST_DEC: 393132718Skan case POST_INC: 394132718Skan case POST_MODIFY: 395132718Skan return nonzero_address_p (XEXP (x, 0)); 396132718Skan 397132718Skan case LO_SUM: 398132718Skan return nonzero_address_p (XEXP (x, 1)); 399132718Skan 400132718Skan default: 401132718Skan break; 402132718Skan } 403132718Skan 404132718Skan /* If it isn't one of the case above, might be zero. */ 405132718Skan return false; 406132718Skan} 407132718Skan 408117395Skan/* Return 1 if X refers to a memory location whose address 40918334Speter cannot be compared reliably with constant addresses, 410117395Skan or if X refers to a BLKmode memory object. 41190075Sobrien FOR_ALIAS is nonzero if we are called from alias analysis; if it is 41290075Sobrien zero, we are slightly more conservative. */ 41318334Speter 41418334Speterint 415132718Skanrtx_addr_varies_p (rtx x, int for_alias) 41618334Speter{ 41790075Sobrien enum rtx_code code; 41890075Sobrien int i; 41990075Sobrien const char *fmt; 42018334Speter 42118334Speter if (x == 0) 42218334Speter return 0; 42318334Speter 42418334Speter code = GET_CODE (x); 42518334Speter if (code == MEM) 42690075Sobrien return GET_MODE (x) == BLKmode || rtx_varies_p (XEXP (x, 0), for_alias); 42718334Speter 42818334Speter fmt = GET_RTX_FORMAT (code); 42918334Speter for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) 43018334Speter if (fmt[i] == 'e') 43150397Sobrien { 43290075Sobrien if (rtx_addr_varies_p (XEXP (x, i), for_alias)) 43350397Sobrien return 1; 43450397Sobrien } 43550397Sobrien else if (fmt[i] == 'E') 43650397Sobrien { 43750397Sobrien int j; 43850397Sobrien for (j = 0; j < XVECLEN (x, i); j++) 43990075Sobrien if (rtx_addr_varies_p (XVECEXP (x, i, j), for_alias)) 44050397Sobrien return 1; 44150397Sobrien } 44218334Speter return 0; 44318334Speter} 44418334Speter 44518334Speter/* Return the value of the integer term in X, if one is apparent; 44618334Speter otherwise return 0. 44718334Speter Only obvious integer terms are detected. 44890075Sobrien This is used in cse.c with the `related_value' field. */ 44918334Speter 45018334SpeterHOST_WIDE_INT 451132718Skanget_integer_term (rtx x) 45218334Speter{ 45318334Speter if (GET_CODE (x) == CONST) 45418334Speter x = XEXP (x, 0); 45518334Speter 45618334Speter if (GET_CODE (x) == MINUS 45718334Speter && GET_CODE (XEXP (x, 1)) == CONST_INT) 45818334Speter return - INTVAL (XEXP (x, 1)); 45918334Speter if (GET_CODE (x) == PLUS 46018334Speter && GET_CODE (XEXP (x, 1)) == CONST_INT) 46118334Speter return INTVAL (XEXP (x, 1)); 46218334Speter return 0; 46318334Speter} 46418334Speter 46518334Speter/* If X is a constant, return the value sans apparent integer term; 46618334Speter otherwise return 0. 46718334Speter Only obvious integer terms are detected. */ 46818334Speter 46918334Speterrtx 470132718Skanget_related_value (rtx x) 47118334Speter{ 47218334Speter if (GET_CODE (x) != CONST) 47318334Speter return 0; 47418334Speter x = XEXP (x, 0); 47518334Speter if (GET_CODE (x) == PLUS 47618334Speter && GET_CODE (XEXP (x, 1)) == CONST_INT) 47718334Speter return XEXP (x, 0); 47818334Speter else if (GET_CODE (x) == MINUS 47918334Speter && GET_CODE (XEXP (x, 1)) == CONST_INT) 48018334Speter return XEXP (x, 0); 48118334Speter return 0; 48218334Speter} 48318334Speter 48490075Sobrien/* Return the number of places FIND appears within X. If COUNT_DEST is 48590075Sobrien zero, we do not count occurrences inside the destination of a SET. */ 48690075Sobrien 48790075Sobrienint 488132718Skancount_occurrences (rtx x, rtx find, int count_dest) 48990075Sobrien{ 49090075Sobrien int i, j; 49190075Sobrien enum rtx_code code; 49290075Sobrien const char *format_ptr; 49390075Sobrien int count; 49490075Sobrien 49590075Sobrien if (x == find) 49690075Sobrien return 1; 49790075Sobrien 49890075Sobrien code = GET_CODE (x); 49990075Sobrien 50090075Sobrien switch (code) 50190075Sobrien { 50290075Sobrien case REG: 50390075Sobrien case CONST_INT: 50490075Sobrien case CONST_DOUBLE: 50596263Sobrien case CONST_VECTOR: 50690075Sobrien case SYMBOL_REF: 50790075Sobrien case CODE_LABEL: 50890075Sobrien case PC: 50990075Sobrien case CC0: 51090075Sobrien return 0; 51190075Sobrien 51290075Sobrien case MEM: 513169689Skan if (MEM_P (find) && rtx_equal_p (x, find)) 51490075Sobrien return 1; 51590075Sobrien break; 51690075Sobrien 51790075Sobrien case SET: 51890075Sobrien if (SET_DEST (x) == find && ! count_dest) 51990075Sobrien return count_occurrences (SET_SRC (x), find, count_dest); 52090075Sobrien break; 52190075Sobrien 52290075Sobrien default: 52390075Sobrien break; 52490075Sobrien } 52590075Sobrien 52690075Sobrien format_ptr = GET_RTX_FORMAT (code); 52790075Sobrien count = 0; 52890075Sobrien 52990075Sobrien for (i = 0; i < GET_RTX_LENGTH (code); i++) 53090075Sobrien { 53190075Sobrien switch (*format_ptr++) 53290075Sobrien { 53390075Sobrien case 'e': 53490075Sobrien count += count_occurrences (XEXP (x, i), find, count_dest); 53590075Sobrien break; 53690075Sobrien 53790075Sobrien case 'E': 53890075Sobrien for (j = 0; j < XVECLEN (x, i); j++) 53990075Sobrien count += count_occurrences (XVECEXP (x, i, j), find, count_dest); 54090075Sobrien break; 54190075Sobrien } 54290075Sobrien } 54390075Sobrien return count; 54490075Sobrien} 54590075Sobrien 54618334Speter/* Nonzero if register REG appears somewhere within IN. 54718334Speter Also works if REG is not a register; in this case it checks 54818334Speter for a subexpression of IN that is Lisp "equal" to REG. */ 54918334Speter 55018334Speterint 551132718Skanreg_mentioned_p (rtx reg, rtx in) 55218334Speter{ 55390075Sobrien const char *fmt; 55490075Sobrien int i; 55590075Sobrien enum rtx_code code; 55618334Speter 55718334Speter if (in == 0) 55818334Speter return 0; 55918334Speter 56018334Speter if (reg == in) 56118334Speter return 1; 56218334Speter 56318334Speter if (GET_CODE (in) == LABEL_REF) 56418334Speter return reg == XEXP (in, 0); 56518334Speter 56618334Speter code = GET_CODE (in); 56718334Speter 56818334Speter switch (code) 56918334Speter { 57018334Speter /* Compare registers by number. */ 57118334Speter case REG: 572169689Skan return REG_P (reg) && REGNO (in) == REGNO (reg); 57318334Speter 57418334Speter /* These codes have no constituent expressions 57518334Speter and are unique. */ 57618334Speter case SCRATCH: 57718334Speter case CC0: 57818334Speter case PC: 57918334Speter return 0; 58018334Speter 58118334Speter case CONST_INT: 58296263Sobrien case CONST_VECTOR: 58318334Speter case CONST_DOUBLE: 58418334Speter /* These are kept unique for a given value. */ 58518334Speter return 0; 586117395Skan 58750397Sobrien default: 58850397Sobrien break; 58918334Speter } 59018334Speter 59118334Speter if (GET_CODE (reg) == code && rtx_equal_p (reg, in)) 59218334Speter return 1; 59318334Speter 59418334Speter fmt = GET_RTX_FORMAT (code); 59518334Speter 59618334Speter for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) 59718334Speter { 59818334Speter if (fmt[i] == 'E') 59918334Speter { 60090075Sobrien int j; 60118334Speter for (j = XVECLEN (in, i) - 1; j >= 0; j--) 60218334Speter if (reg_mentioned_p (reg, XVECEXP (in, i, j))) 60318334Speter return 1; 60418334Speter } 60518334Speter else if (fmt[i] == 'e' 60618334Speter && reg_mentioned_p (reg, XEXP (in, i))) 60718334Speter return 1; 60818334Speter } 60918334Speter return 0; 61018334Speter} 61118334Speter 61218334Speter/* Return 1 if in between BEG and END, exclusive of BEG and END, there is 61318334Speter no CODE_LABEL insn. */ 61418334Speter 61518334Speterint 616132718Skanno_labels_between_p (rtx beg, rtx end) 61718334Speter{ 61890075Sobrien rtx p; 61990075Sobrien if (beg == end) 62090075Sobrien return 0; 62118334Speter for (p = NEXT_INSN (beg); p != end; p = NEXT_INSN (p)) 622169689Skan if (LABEL_P (p)) 62318334Speter return 0; 62418334Speter return 1; 62518334Speter} 62618334Speter 62718334Speter/* Nonzero if register REG is used in an insn between 62818334Speter FROM_INSN and TO_INSN (exclusive of those two). */ 62918334Speter 63018334Speterint 631132718Skanreg_used_between_p (rtx reg, rtx from_insn, rtx to_insn) 63218334Speter{ 63390075Sobrien rtx insn; 63418334Speter 63518334Speter if (from_insn == to_insn) 63618334Speter return 0; 63718334Speter 63818334Speter for (insn = NEXT_INSN (from_insn); insn != to_insn; insn = NEXT_INSN (insn)) 63990075Sobrien if (INSN_P (insn) 64018334Speter && (reg_overlap_mentioned_p (reg, PATTERN (insn)) 641169689Skan || (CALL_P (insn) && find_reg_fusage (insn, USE, reg)))) 64218334Speter return 1; 64318334Speter return 0; 64418334Speter} 64518334Speter 64618334Speter/* Nonzero if the old value of X, a register, is referenced in BODY. If X 64718334Speter is entirely replaced by a new value and the only use is as a SET_DEST, 64818334Speter we do not consider it a reference. */ 64918334Speter 65018334Speterint 651132718Skanreg_referenced_p (rtx x, rtx body) 65218334Speter{ 65318334Speter int i; 65418334Speter 65518334Speter switch (GET_CODE (body)) 65618334Speter { 65718334Speter case SET: 65818334Speter if (reg_overlap_mentioned_p (x, SET_SRC (body))) 65918334Speter return 1; 66018334Speter 66118334Speter /* If the destination is anything other than CC0, PC, a REG or a SUBREG 66218334Speter of a REG that occupies all of the REG, the insn references X if 66318334Speter it is mentioned in the destination. */ 66418334Speter if (GET_CODE (SET_DEST (body)) != CC0 66518334Speter && GET_CODE (SET_DEST (body)) != PC 666169689Skan && !REG_P (SET_DEST (body)) 66718334Speter && ! (GET_CODE (SET_DEST (body)) == SUBREG 668169689Skan && REG_P (SUBREG_REG (SET_DEST (body))) 66918334Speter && (((GET_MODE_SIZE (GET_MODE (SUBREG_REG (SET_DEST (body)))) 67018334Speter + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD) 67118334Speter == ((GET_MODE_SIZE (GET_MODE (SET_DEST (body))) 67218334Speter + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD))) 67318334Speter && reg_overlap_mentioned_p (x, SET_DEST (body))) 67418334Speter return 1; 67550397Sobrien return 0; 67618334Speter 67718334Speter case ASM_OPERANDS: 67818334Speter for (i = ASM_OPERANDS_INPUT_LENGTH (body) - 1; i >= 0; i--) 67918334Speter if (reg_overlap_mentioned_p (x, ASM_OPERANDS_INPUT (body, i))) 68018334Speter return 1; 68150397Sobrien return 0; 68218334Speter 68318334Speter case CALL: 68418334Speter case USE: 68590075Sobrien case IF_THEN_ELSE: 68618334Speter return reg_overlap_mentioned_p (x, body); 68718334Speter 68818334Speter case TRAP_IF: 68918334Speter return reg_overlap_mentioned_p (x, TRAP_CONDITION (body)); 69018334Speter 69190075Sobrien case PREFETCH: 69290075Sobrien return reg_overlap_mentioned_p (x, XEXP (body, 0)); 69390075Sobrien 69418334Speter case UNSPEC: 69518334Speter case UNSPEC_VOLATILE: 69690075Sobrien for (i = XVECLEN (body, 0) - 1; i >= 0; i--) 69790075Sobrien if (reg_overlap_mentioned_p (x, XVECEXP (body, 0, i))) 69890075Sobrien return 1; 69990075Sobrien return 0; 70090075Sobrien 70118334Speter case PARALLEL: 70218334Speter for (i = XVECLEN (body, 0) - 1; i >= 0; i--) 70318334Speter if (reg_referenced_p (x, XVECEXP (body, 0, i))) 70418334Speter return 1; 70550397Sobrien return 0; 706117395Skan 70790075Sobrien case CLOBBER: 708169689Skan if (MEM_P (XEXP (body, 0))) 70990075Sobrien if (reg_overlap_mentioned_p (x, XEXP (XEXP (body, 0), 0))) 71090075Sobrien return 1; 71190075Sobrien return 0; 71290075Sobrien 71390075Sobrien case COND_EXEC: 71490075Sobrien if (reg_overlap_mentioned_p (x, COND_EXEC_TEST (body))) 71590075Sobrien return 1; 71690075Sobrien return reg_referenced_p (x, COND_EXEC_CODE (body)); 71790075Sobrien 71850397Sobrien default: 71950397Sobrien return 0; 72018334Speter } 72118334Speter} 72218334Speter 72318334Speter/* Nonzero if register REG is set or clobbered in an insn between 72418334Speter FROM_INSN and TO_INSN (exclusive of those two). */ 72518334Speter 72618334Speterint 727132718Skanreg_set_between_p (rtx reg, rtx from_insn, rtx to_insn) 72818334Speter{ 72990075Sobrien rtx insn; 73018334Speter 73118334Speter if (from_insn == to_insn) 73218334Speter return 0; 73318334Speter 73418334Speter for (insn = NEXT_INSN (from_insn); insn != to_insn; insn = NEXT_INSN (insn)) 73590075Sobrien if (INSN_P (insn) && reg_set_p (reg, insn)) 73618334Speter return 1; 73718334Speter return 0; 73818334Speter} 73918334Speter 74018334Speter/* Internals of reg_set_between_p. */ 74118334Speterint 742132718Skanreg_set_p (rtx reg, rtx insn) 74318334Speter{ 74418334Speter /* We can be passed an insn or part of one. If we are passed an insn, 74518334Speter check if a side-effect of the insn clobbers REG. */ 746132718Skan if (INSN_P (insn) 747132718Skan && (FIND_REG_INC_NOTE (insn, reg) 748169689Skan || (CALL_P (insn) 749169689Skan && ((REG_P (reg) 750169689Skan && REGNO (reg) < FIRST_PSEUDO_REGISTER 751259268Spfg && overlaps_hard_reg_set_p (regs_invalidated_by_call, 752259268Spfg GET_MODE (reg), REGNO (reg))) 753169689Skan || MEM_P (reg) 754132718Skan || find_reg_fusage (insn, CLOBBER, reg))))) 755132718Skan return 1; 75618334Speter 75790075Sobrien return set_of (reg, insn) != NULL_RTX; 75818334Speter} 75918334Speter 76018334Speter/* Similar to reg_set_between_p, but check all registers in X. Return 0 76118334Speter only if none of them are modified between START and END. Return 1 if 762132718Skan X contains a MEM; this routine does usememory aliasing. */ 76318334Speter 76418334Speterint 765132718Skanmodified_between_p (rtx x, rtx start, rtx end) 76618334Speter{ 76718334Speter enum rtx_code code = GET_CODE (x); 76890075Sobrien const char *fmt; 76918334Speter int i, j; 770132718Skan rtx insn; 77118334Speter 772132718Skan if (start == end) 773132718Skan return 0; 774132718Skan 77518334Speter switch (code) 77618334Speter { 77718334Speter case CONST_INT: 77818334Speter case CONST_DOUBLE: 77996263Sobrien case CONST_VECTOR: 78018334Speter case CONST: 78118334Speter case SYMBOL_REF: 78218334Speter case LABEL_REF: 78318334Speter return 0; 78418334Speter 78518334Speter case PC: 78618334Speter case CC0: 78718334Speter return 1; 78818334Speter 78918334Speter case MEM: 790132718Skan if (modified_between_p (XEXP (x, 0), start, end)) 79118334Speter return 1; 792169689Skan if (MEM_READONLY_P (x)) 793169689Skan return 0; 794132718Skan for (insn = NEXT_INSN (start); insn != end; insn = NEXT_INSN (insn)) 795132718Skan if (memory_modified_in_insn_p (x, insn)) 796132718Skan return 1; 797132718Skan return 0; 79818334Speter break; 79918334Speter 80018334Speter case REG: 80118334Speter return reg_set_between_p (x, start, end); 802117395Skan 80350397Sobrien default: 80450397Sobrien break; 80518334Speter } 80618334Speter 80718334Speter fmt = GET_RTX_FORMAT (code); 80818334Speter for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) 80918334Speter { 81018334Speter if (fmt[i] == 'e' && modified_between_p (XEXP (x, i), start, end)) 81118334Speter return 1; 81218334Speter 81390075Sobrien else if (fmt[i] == 'E') 81418334Speter for (j = XVECLEN (x, i) - 1; j >= 0; j--) 81518334Speter if (modified_between_p (XVECEXP (x, i, j), start, end)) 81618334Speter return 1; 81718334Speter } 81818334Speter 81918334Speter return 0; 82018334Speter} 82118334Speter 82218334Speter/* Similar to reg_set_p, but check all registers in X. Return 0 only if none 82318334Speter of them are modified in INSN. Return 1 if X contains a MEM; this routine 824132718Skan does use memory aliasing. */ 82518334Speter 82618334Speterint 827132718Skanmodified_in_p (rtx x, rtx insn) 82818334Speter{ 82918334Speter enum rtx_code code = GET_CODE (x); 83090075Sobrien const char *fmt; 83118334Speter int i, j; 83218334Speter 83318334Speter switch (code) 83418334Speter { 83518334Speter case CONST_INT: 83618334Speter case CONST_DOUBLE: 83796263Sobrien case CONST_VECTOR: 83818334Speter case CONST: 83918334Speter case SYMBOL_REF: 84018334Speter case LABEL_REF: 84118334Speter return 0; 84218334Speter 84318334Speter case PC: 84418334Speter case CC0: 84518334Speter return 1; 84618334Speter 84718334Speter case MEM: 848132718Skan if (modified_in_p (XEXP (x, 0), insn)) 84918334Speter return 1; 850169689Skan if (MEM_READONLY_P (x)) 851169689Skan return 0; 852132718Skan if (memory_modified_in_insn_p (x, insn)) 853132718Skan return 1; 854132718Skan return 0; 85518334Speter break; 85618334Speter 85718334Speter case REG: 85818334Speter return reg_set_p (x, insn); 85950397Sobrien 86050397Sobrien default: 86150397Sobrien break; 86218334Speter } 86318334Speter 86418334Speter fmt = GET_RTX_FORMAT (code); 86518334Speter for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) 86618334Speter { 86718334Speter if (fmt[i] == 'e' && modified_in_p (XEXP (x, i), insn)) 86818334Speter return 1; 86918334Speter 87090075Sobrien else if (fmt[i] == 'E') 87118334Speter for (j = XVECLEN (x, i) - 1; j >= 0; j--) 87218334Speter if (modified_in_p (XVECEXP (x, i, j), insn)) 87318334Speter return 1; 87418334Speter } 87518334Speter 87618334Speter return 0; 87718334Speter} 87818334Speter 87990075Sobrien/* Helper function for set_of. */ 88090075Sobrienstruct set_of_data 88190075Sobrien { 88290075Sobrien rtx found; 88390075Sobrien rtx pat; 88490075Sobrien }; 88590075Sobrien 88690075Sobrienstatic void 887132718Skanset_of_1 (rtx x, rtx pat, void *data1) 88890075Sobrien{ 88990075Sobrien struct set_of_data *data = (struct set_of_data *) (data1); 89090075Sobrien if (rtx_equal_p (x, data->pat) 891169689Skan || (!MEM_P (x) && reg_overlap_mentioned_p (data->pat, x))) 89290075Sobrien data->found = pat; 89390075Sobrien} 89490075Sobrien 89590075Sobrien/* Give an INSN, return a SET or CLOBBER expression that does modify PAT 89690075Sobrien (either directly or via STRICT_LOW_PART and similar modifiers). */ 89790075Sobrienrtx 898132718Skanset_of (rtx pat, rtx insn) 89990075Sobrien{ 90090075Sobrien struct set_of_data data; 90190075Sobrien data.found = NULL_RTX; 90290075Sobrien data.pat = pat; 90390075Sobrien note_stores (INSN_P (insn) ? PATTERN (insn) : insn, set_of_1, &data); 90490075Sobrien return data.found; 90590075Sobrien} 90690075Sobrien 90718334Speter/* Given an INSN, return a SET expression if this insn has only a single SET. 90818334Speter It may also have CLOBBERs, USEs, or SET whose output 90918334Speter will not be used, which we ignore. */ 91018334Speter 91118334Speterrtx 912132718Skansingle_set_2 (rtx insn, rtx pat) 91318334Speter{ 91490075Sobrien rtx set = NULL; 91590075Sobrien int set_verified = 1; 91618334Speter int i; 91718334Speter 91890075Sobrien if (GET_CODE (pat) == PARALLEL) 91918334Speter { 92090075Sobrien for (i = 0; i < XVECLEN (pat, 0); i++) 92190075Sobrien { 92290075Sobrien rtx sub = XVECEXP (pat, 0, i); 92390075Sobrien switch (GET_CODE (sub)) 92490075Sobrien { 92590075Sobrien case USE: 92690075Sobrien case CLOBBER: 92790075Sobrien break; 92890075Sobrien 92990075Sobrien case SET: 93090075Sobrien /* We can consider insns having multiple sets, where all 93190075Sobrien but one are dead as single set insns. In common case 93290075Sobrien only single set is present in the pattern so we want 93390075Sobrien to avoid checking for REG_UNUSED notes unless necessary. 93490075Sobrien 93590075Sobrien When we reach set first time, we just expect this is 93690075Sobrien the single set we are looking for and only when more 93790075Sobrien sets are found in the insn, we check them. */ 93890075Sobrien if (!set_verified) 93990075Sobrien { 94090075Sobrien if (find_reg_note (insn, REG_UNUSED, SET_DEST (set)) 94190075Sobrien && !side_effects_p (set)) 94290075Sobrien set = NULL; 94390075Sobrien else 94490075Sobrien set_verified = 1; 94590075Sobrien } 94690075Sobrien if (!set) 94790075Sobrien set = sub, set_verified = 0; 94890075Sobrien else if (!find_reg_note (insn, REG_UNUSED, SET_DEST (sub)) 94990075Sobrien || side_effects_p (sub)) 95090075Sobrien return NULL_RTX; 95190075Sobrien break; 95290075Sobrien 95390075Sobrien default: 95490075Sobrien return NULL_RTX; 95590075Sobrien } 95690075Sobrien } 95718334Speter } 95890075Sobrien return set; 95918334Speter} 96052284Sobrien 96152284Sobrien/* Given an INSN, return nonzero if it has more than one SET, else return 96252284Sobrien zero. */ 96352284Sobrien 96452284Sobrienint 965132718Skanmultiple_sets (rtx insn) 96652284Sobrien{ 96752284Sobrien int found; 96852284Sobrien int i; 969117395Skan 97052284Sobrien /* INSN must be an insn. */ 97190075Sobrien if (! INSN_P (insn)) 97252284Sobrien return 0; 97352284Sobrien 97452284Sobrien /* Only a PARALLEL can have multiple SETs. */ 97552284Sobrien if (GET_CODE (PATTERN (insn)) == PARALLEL) 97652284Sobrien { 97752284Sobrien for (i = 0, found = 0; i < XVECLEN (PATTERN (insn), 0); i++) 97852284Sobrien if (GET_CODE (XVECEXP (PATTERN (insn), 0, i)) == SET) 97952284Sobrien { 98052284Sobrien /* If we have already found a SET, then return now. */ 98152284Sobrien if (found) 98252284Sobrien return 1; 98352284Sobrien else 98452284Sobrien found = 1; 98552284Sobrien } 98652284Sobrien } 987117395Skan 98852284Sobrien /* Either zero or one SET. */ 98952284Sobrien return 0; 99052284Sobrien} 99118334Speter 99290075Sobrien/* Return nonzero if the destination of SET equals the source 99390075Sobrien and there are no side effects. */ 99418334Speter 99590075Sobrienint 996132718Skanset_noop_p (rtx set) 99790075Sobrien{ 99890075Sobrien rtx src = SET_SRC (set); 99990075Sobrien rtx dst = SET_DEST (set); 100090075Sobrien 1001132718Skan if (dst == pc_rtx && src == pc_rtx) 1002132718Skan return 1; 100390075Sobrien 1004169689Skan if (MEM_P (dst) && MEM_P (src)) 1005132718Skan return rtx_equal_p (dst, src) && !side_effects_p (dst); 100690075Sobrien 1007169689Skan if (GET_CODE (dst) == ZERO_EXTRACT) 100890075Sobrien return rtx_equal_p (XEXP (dst, 0), src) 1009132718Skan && ! BYTES_BIG_ENDIAN && XEXP (dst, 2) == const0_rtx 1010132718Skan && !side_effects_p (src); 101190075Sobrien 101290075Sobrien if (GET_CODE (dst) == STRICT_LOW_PART) 101390075Sobrien dst = XEXP (dst, 0); 101490075Sobrien 101590075Sobrien if (GET_CODE (src) == SUBREG && GET_CODE (dst) == SUBREG) 101690075Sobrien { 101790075Sobrien if (SUBREG_BYTE (src) != SUBREG_BYTE (dst)) 101890075Sobrien return 0; 101990075Sobrien src = SUBREG_REG (src); 102090075Sobrien dst = SUBREG_REG (dst); 102190075Sobrien } 102290075Sobrien 1023169689Skan return (REG_P (src) && REG_P (dst) 102490075Sobrien && REGNO (src) == REGNO (dst)); 102590075Sobrien} 102690075Sobrien 102790075Sobrien/* Return nonzero if an insn consists only of SETs, each of which only sets a 102890075Sobrien value to itself. */ 102990075Sobrien 103090075Sobrienint 1031132718Skannoop_move_p (rtx insn) 103290075Sobrien{ 103390075Sobrien rtx pat = PATTERN (insn); 103490075Sobrien 103590075Sobrien if (INSN_CODE (insn) == NOOP_MOVE_INSN_CODE) 103690075Sobrien return 1; 103790075Sobrien 103890075Sobrien /* Insns carrying these notes are useful later on. */ 103990075Sobrien if (find_reg_note (insn, REG_EQUAL, NULL_RTX)) 104090075Sobrien return 0; 104190075Sobrien 104290075Sobrien /* For now treat an insn with a REG_RETVAL note as a 104390075Sobrien a special insn which should not be considered a no-op. */ 104490075Sobrien if (find_reg_note (insn, REG_RETVAL, NULL_RTX)) 104590075Sobrien return 0; 104690075Sobrien 104790075Sobrien if (GET_CODE (pat) == SET && set_noop_p (pat)) 104890075Sobrien return 1; 104990075Sobrien 105090075Sobrien if (GET_CODE (pat) == PARALLEL) 105190075Sobrien { 105290075Sobrien int i; 105390075Sobrien /* If nothing but SETs of registers to themselves, 105490075Sobrien this insn can also be deleted. */ 105590075Sobrien for (i = 0; i < XVECLEN (pat, 0); i++) 105690075Sobrien { 105790075Sobrien rtx tem = XVECEXP (pat, 0, i); 105890075Sobrien 105990075Sobrien if (GET_CODE (tem) == USE 106090075Sobrien || GET_CODE (tem) == CLOBBER) 106190075Sobrien continue; 106290075Sobrien 106390075Sobrien if (GET_CODE (tem) != SET || ! set_noop_p (tem)) 106490075Sobrien return 0; 106590075Sobrien } 106690075Sobrien 106790075Sobrien return 1; 106890075Sobrien } 106990075Sobrien return 0; 107090075Sobrien} 107190075Sobrien 107290075Sobrien 107390075Sobrien/* Return the last thing that X was assigned from before *PINSN. If VALID_TO 107490075Sobrien is not NULL_RTX then verify that the object is not modified up to VALID_TO. 107590075Sobrien If the object was modified, if we hit a partial assignment to X, or hit a 107690075Sobrien CODE_LABEL first, return X. If we found an assignment, update *PINSN to 107790075Sobrien point to it. ALLOW_HWREG is set to 1 if hardware registers are allowed to 107890075Sobrien be the src. */ 107990075Sobrien 108018334Speterrtx 1081132718Skanfind_last_value (rtx x, rtx *pinsn, rtx valid_to, int allow_hwreg) 108218334Speter{ 108318334Speter rtx p; 108418334Speter 1085169689Skan for (p = PREV_INSN (*pinsn); p && !LABEL_P (p); 108618334Speter p = PREV_INSN (p)) 108790075Sobrien if (INSN_P (p)) 108818334Speter { 108918334Speter rtx set = single_set (p); 109018334Speter rtx note = find_reg_note (p, REG_EQUAL, NULL_RTX); 109118334Speter 109218334Speter if (set && rtx_equal_p (x, SET_DEST (set))) 109318334Speter { 109418334Speter rtx src = SET_SRC (set); 109518334Speter 109618334Speter if (note && GET_CODE (XEXP (note, 0)) != EXPR_LIST) 109718334Speter src = XEXP (note, 0); 109818334Speter 109990075Sobrien if ((valid_to == NULL_RTX 110090075Sobrien || ! modified_between_p (src, PREV_INSN (p), valid_to)) 110118334Speter /* Reject hard registers because we don't usually want 110218334Speter to use them; we'd rather use a pseudo. */ 1103169689Skan && (! (REG_P (src) 110452284Sobrien && REGNO (src) < FIRST_PSEUDO_REGISTER) || allow_hwreg)) 110518334Speter { 110618334Speter *pinsn = p; 110718334Speter return src; 110818334Speter } 110918334Speter } 1110117395Skan 111118334Speter /* If set in non-simple way, we don't have a value. */ 111218334Speter if (reg_set_p (x, p)) 111318334Speter break; 111418334Speter } 111518334Speter 111618334Speter return x; 1117117395Skan} 111818334Speter 111918334Speter/* Return nonzero if register in range [REGNO, ENDREGNO) 112018334Speter appears either explicitly or implicitly in X 112118334Speter other than being stored into. 112218334Speter 112318334Speter References contained within the substructure at LOC do not count. 112418334Speter LOC may be zero, meaning don't ignore anything. */ 112518334Speter 112618334Speterint 1127132718Skanrefers_to_regno_p (unsigned int regno, unsigned int endregno, rtx x, 1128132718Skan rtx *loc) 112918334Speter{ 113090075Sobrien int i; 113190075Sobrien unsigned int x_regno; 113290075Sobrien RTX_CODE code; 113390075Sobrien const char *fmt; 113418334Speter 113518334Speter repeat: 113618334Speter /* The contents of a REG_NONNEG note is always zero, so we must come here 113718334Speter upon repeat in case the last REG_NOTE is a REG_NONNEG note. */ 113818334Speter if (x == 0) 113918334Speter return 0; 114018334Speter 114118334Speter code = GET_CODE (x); 114218334Speter 114318334Speter switch (code) 114418334Speter { 114518334Speter case REG: 114690075Sobrien x_regno = REGNO (x); 114718334Speter 114818334Speter /* If we modifying the stack, frame, or argument pointer, it will 114918334Speter clobber a virtual register. In fact, we could be more precise, 115018334Speter but it isn't worth it. */ 115190075Sobrien if ((x_regno == STACK_POINTER_REGNUM 115218334Speter#if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM 115390075Sobrien || x_regno == ARG_POINTER_REGNUM 115418334Speter#endif 115590075Sobrien || x_regno == FRAME_POINTER_REGNUM) 115618334Speter && regno >= FIRST_VIRTUAL_REGISTER && regno <= LAST_VIRTUAL_REGISTER) 115718334Speter return 1; 115818334Speter 115990075Sobrien return (endregno > x_regno 1160117395Skan && regno < x_regno + (x_regno < FIRST_PSEUDO_REGISTER 1161169689Skan ? hard_regno_nregs[x_regno][GET_MODE (x)] 116218334Speter : 1)); 116318334Speter 116418334Speter case SUBREG: 116518334Speter /* If this is a SUBREG of a hard reg, we can see exactly which 116618334Speter registers are being modified. Otherwise, handle normally. */ 1167169689Skan if (REG_P (SUBREG_REG (x)) 116818334Speter && REGNO (SUBREG_REG (x)) < FIRST_PSEUDO_REGISTER) 116918334Speter { 117090075Sobrien unsigned int inner_regno = subreg_regno (x); 117190075Sobrien unsigned int inner_endregno 117218334Speter = inner_regno + (inner_regno < FIRST_PSEUDO_REGISTER 1173169689Skan ? hard_regno_nregs[inner_regno][GET_MODE (x)] : 1); 117418334Speter 117518334Speter return endregno > inner_regno && regno < inner_endregno; 117618334Speter } 117718334Speter break; 117818334Speter 117918334Speter case CLOBBER: 118018334Speter case SET: 118118334Speter if (&SET_DEST (x) != loc 118218334Speter /* Note setting a SUBREG counts as referring to the REG it is in for 118318334Speter a pseudo but not for hard registers since we can 118418334Speter treat each word individually. */ 118518334Speter && ((GET_CODE (SET_DEST (x)) == SUBREG 118618334Speter && loc != &SUBREG_REG (SET_DEST (x)) 1187169689Skan && REG_P (SUBREG_REG (SET_DEST (x))) 118818334Speter && REGNO (SUBREG_REG (SET_DEST (x))) >= FIRST_PSEUDO_REGISTER 118918334Speter && refers_to_regno_p (regno, endregno, 119018334Speter SUBREG_REG (SET_DEST (x)), loc)) 1191169689Skan || (!REG_P (SET_DEST (x)) 119218334Speter && refers_to_regno_p (regno, endregno, SET_DEST (x), loc)))) 119318334Speter return 1; 119418334Speter 119518334Speter if (code == CLOBBER || loc == &SET_SRC (x)) 119618334Speter return 0; 119718334Speter x = SET_SRC (x); 119818334Speter goto repeat; 119950397Sobrien 120050397Sobrien default: 120150397Sobrien break; 120218334Speter } 120318334Speter 120418334Speter /* X does not match, so try its subexpressions. */ 120518334Speter 120618334Speter fmt = GET_RTX_FORMAT (code); 120718334Speter for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) 120818334Speter { 120918334Speter if (fmt[i] == 'e' && loc != &XEXP (x, i)) 121018334Speter { 121118334Speter if (i == 0) 121218334Speter { 121318334Speter x = XEXP (x, 0); 121418334Speter goto repeat; 121518334Speter } 121618334Speter else 121718334Speter if (refers_to_regno_p (regno, endregno, XEXP (x, i), loc)) 121818334Speter return 1; 121918334Speter } 122018334Speter else if (fmt[i] == 'E') 122118334Speter { 122290075Sobrien int j; 1223132718Skan for (j = XVECLEN (x, i) - 1; j >= 0; j--) 122418334Speter if (loc != &XVECEXP (x, i, j) 122518334Speter && refers_to_regno_p (regno, endregno, XVECEXP (x, i, j), loc)) 122618334Speter return 1; 122718334Speter } 122818334Speter } 122918334Speter return 0; 123018334Speter} 123118334Speter 123218334Speter/* Nonzero if modifying X will affect IN. If X is a register or a SUBREG, 123318334Speter we check if any register number in X conflicts with the relevant register 123418334Speter numbers. If X is a constant, return 0. If X is a MEM, return 1 iff IN 123518334Speter contains a MEM (we don't bother checking for memory addresses that can't 123618334Speter conflict because we expect this to be a rare case. */ 123718334Speter 123818334Speterint 1239132718Skanreg_overlap_mentioned_p (rtx x, rtx in) 124018334Speter{ 124190075Sobrien unsigned int regno, endregno; 124218334Speter 1243169689Skan /* If either argument is a constant, then modifying X can not 1244169689Skan affect IN. Here we look at IN, we can profitably combine 1245169689Skan CONSTANT_P (x) with the switch statement below. */ 1246169689Skan if (CONSTANT_P (in)) 124750397Sobrien return 0; 124890075Sobrien 1249169689Skan recurse: 125090075Sobrien switch (GET_CODE (x)) 125118334Speter { 1252169689Skan case STRICT_LOW_PART: 1253169689Skan case ZERO_EXTRACT: 1254169689Skan case SIGN_EXTRACT: 1255169689Skan /* Overly conservative. */ 1256169689Skan x = XEXP (x, 0); 1257169689Skan goto recurse; 1258169689Skan 125990075Sobrien case SUBREG: 126018334Speter regno = REGNO (SUBREG_REG (x)); 126118334Speter if (regno < FIRST_PSEUDO_REGISTER) 126290075Sobrien regno = subreg_regno (x); 126390075Sobrien goto do_reg; 126418334Speter 126590075Sobrien case REG: 126690075Sobrien regno = REGNO (x); 126790075Sobrien do_reg: 126890075Sobrien endregno = regno + (regno < FIRST_PSEUDO_REGISTER 1269169689Skan ? hard_regno_nregs[regno][GET_MODE (x)] : 1); 127090075Sobrien return refers_to_regno_p (regno, endregno, in, (rtx*) 0); 127118334Speter 127290075Sobrien case MEM: 127390075Sobrien { 127490075Sobrien const char *fmt; 127590075Sobrien int i; 127618334Speter 1277169689Skan if (MEM_P (in)) 127818334Speter return 1; 127918334Speter 128090075Sobrien fmt = GET_RTX_FORMAT (GET_CODE (in)); 128190075Sobrien for (i = GET_RTX_LENGTH (GET_CODE (in)) - 1; i >= 0; i--) 1282169689Skan if (fmt[i] == 'e') 1283169689Skan { 1284169689Skan if (reg_overlap_mentioned_p (x, XEXP (in, i))) 1285169689Skan return 1; 1286169689Skan } 1287169689Skan else if (fmt[i] == 'E') 1288169689Skan { 1289169689Skan int j; 1290169689Skan for (j = XVECLEN (in, i) - 1; j >= 0; --j) 1291169689Skan if (reg_overlap_mentioned_p (x, XVECEXP (in, i, j))) 1292169689Skan return 1; 1293169689Skan } 129452284Sobrien 129590075Sobrien return 0; 129690075Sobrien } 129718334Speter 129890075Sobrien case SCRATCH: 129990075Sobrien case PC: 130090075Sobrien case CC0: 130190075Sobrien return reg_mentioned_p (x, in); 130218334Speter 130390075Sobrien case PARALLEL: 130490075Sobrien { 130590075Sobrien int i; 130618334Speter 130790075Sobrien /* If any register in here refers to it we return true. */ 130890075Sobrien for (i = XVECLEN (x, 0) - 1; i >= 0; i--) 130990075Sobrien if (XEXP (XVECEXP (x, 0, i), 0) != 0 131090075Sobrien && reg_overlap_mentioned_p (XEXP (XVECEXP (x, 0, i), 0), in)) 1311169689Skan return 1; 131290075Sobrien return 0; 131390075Sobrien } 131418334Speter 131590075Sobrien default: 1316169689Skan gcc_assert (CONSTANT_P (x)); 1317169689Skan return 0; 131890075Sobrien } 131918334Speter} 132090075Sobrien 132118334Speter/* Call FUN on each register or MEM that is stored into or clobbered by X. 132218334Speter (X would be the pattern of an insn). 132318334Speter FUN receives two arguments: 132418334Speter the REG, MEM, CC0 or PC being stored in or clobbered, 132518334Speter the SET or CLOBBER rtx that does the store. 132618334Speter 132718334Speter If the item being stored in or clobbered is a SUBREG of a hard register, 132818334Speter the SUBREG will be passed. */ 1329117395Skan 133018334Spetervoid 1331132718Skannote_stores (rtx x, void (*fun) (rtx, rtx, void *), void *data) 133218334Speter{ 133390075Sobrien int i; 133490075Sobrien 133590075Sobrien if (GET_CODE (x) == COND_EXEC) 133690075Sobrien x = COND_EXEC_CODE (x); 133790075Sobrien 133890075Sobrien if (GET_CODE (x) == SET || GET_CODE (x) == CLOBBER) 133918334Speter { 134090075Sobrien rtx dest = SET_DEST (x); 134190075Sobrien 134218334Speter while ((GET_CODE (dest) == SUBREG 1343169689Skan && (!REG_P (SUBREG_REG (dest)) 134418334Speter || REGNO (SUBREG_REG (dest)) >= FIRST_PSEUDO_REGISTER)) 134518334Speter || GET_CODE (dest) == ZERO_EXTRACT 134618334Speter || GET_CODE (dest) == STRICT_LOW_PART) 134718334Speter dest = XEXP (dest, 0); 134852284Sobrien 134990075Sobrien /* If we have a PARALLEL, SET_DEST is a list of EXPR_LIST expressions, 135096263Sobrien each of whose first operand is a register. */ 135190075Sobrien if (GET_CODE (dest) == PARALLEL) 135252284Sobrien { 135352284Sobrien for (i = XVECLEN (dest, 0) - 1; i >= 0; i--) 135490075Sobrien if (XEXP (XVECEXP (dest, 0, i), 0) != 0) 135596263Sobrien (*fun) (XEXP (XVECEXP (dest, 0, i), 0), x, data); 135652284Sobrien } 135752284Sobrien else 135890075Sobrien (*fun) (dest, x, data); 135918334Speter } 136090075Sobrien 136118334Speter else if (GET_CODE (x) == PARALLEL) 136290075Sobrien for (i = XVECLEN (x, 0) - 1; i >= 0; i--) 136390075Sobrien note_stores (XVECEXP (x, 0, i), fun, data); 136490075Sobrien} 136590075Sobrien 136690075Sobrien/* Like notes_stores, but call FUN for each expression that is being 136790075Sobrien referenced in PBODY, a pointer to the PATTERN of an insn. We only call 136890075Sobrien FUN for each expression, not any interior subexpressions. FUN receives a 136990075Sobrien pointer to the expression and the DATA passed to this function. 137090075Sobrien 137190075Sobrien Note that this is not quite the same test as that done in reg_referenced_p 137290075Sobrien since that considers something as being referenced if it is being 137390075Sobrien partially set, while we do not. */ 137490075Sobrien 137590075Sobrienvoid 1376132718Skannote_uses (rtx *pbody, void (*fun) (rtx *, void *), void *data) 137790075Sobrien{ 137890075Sobrien rtx body = *pbody; 137990075Sobrien int i; 138090075Sobrien 138190075Sobrien switch (GET_CODE (body)) 138218334Speter { 138390075Sobrien case COND_EXEC: 138490075Sobrien (*fun) (&COND_EXEC_TEST (body), data); 138590075Sobrien note_uses (&COND_EXEC_CODE (body), fun, data); 138690075Sobrien return; 138790075Sobrien 138890075Sobrien case PARALLEL: 138990075Sobrien for (i = XVECLEN (body, 0) - 1; i >= 0; i--) 139090075Sobrien note_uses (&XVECEXP (body, 0, i), fun, data); 139190075Sobrien return; 139290075Sobrien 139390075Sobrien case USE: 139490075Sobrien (*fun) (&XEXP (body, 0), data); 139590075Sobrien return; 139690075Sobrien 139790075Sobrien case ASM_OPERANDS: 139890075Sobrien for (i = ASM_OPERANDS_INPUT_LENGTH (body) - 1; i >= 0; i--) 139990075Sobrien (*fun) (&ASM_OPERANDS_INPUT (body, i), data); 140090075Sobrien return; 140190075Sobrien 140290075Sobrien case TRAP_IF: 140390075Sobrien (*fun) (&TRAP_CONDITION (body), data); 140490075Sobrien return; 140590075Sobrien 140690075Sobrien case PREFETCH: 140790075Sobrien (*fun) (&XEXP (body, 0), data); 140890075Sobrien return; 140990075Sobrien 141090075Sobrien case UNSPEC: 141190075Sobrien case UNSPEC_VOLATILE: 141290075Sobrien for (i = XVECLEN (body, 0) - 1; i >= 0; i--) 141390075Sobrien (*fun) (&XVECEXP (body, 0, i), data); 141490075Sobrien return; 141590075Sobrien 141690075Sobrien case CLOBBER: 1417169689Skan if (MEM_P (XEXP (body, 0))) 141890075Sobrien (*fun) (&XEXP (XEXP (body, 0), 0), data); 141990075Sobrien return; 142090075Sobrien 142190075Sobrien case SET: 142290075Sobrien { 142390075Sobrien rtx dest = SET_DEST (body); 142490075Sobrien 142590075Sobrien /* For sets we replace everything in source plus registers in memory 142690075Sobrien expression in store and operands of a ZERO_EXTRACT. */ 142790075Sobrien (*fun) (&SET_SRC (body), data); 142890075Sobrien 142990075Sobrien if (GET_CODE (dest) == ZERO_EXTRACT) 143090075Sobrien { 143190075Sobrien (*fun) (&XEXP (dest, 1), data); 143290075Sobrien (*fun) (&XEXP (dest, 2), data); 143390075Sobrien } 143490075Sobrien 143590075Sobrien while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART) 143690075Sobrien dest = XEXP (dest, 0); 143790075Sobrien 1438169689Skan if (MEM_P (dest)) 143990075Sobrien (*fun) (&XEXP (dest, 0), data); 144090075Sobrien } 144190075Sobrien return; 144290075Sobrien 144390075Sobrien default: 144490075Sobrien /* All the other possibilities never store. */ 144590075Sobrien (*fun) (pbody, data); 144690075Sobrien return; 144718334Speter } 144818334Speter} 144918334Speter 145018334Speter/* Return nonzero if X's old contents don't survive after INSN. 145118334Speter This will be true if X is (cc0) or if X is a register and 145218334Speter X dies in INSN or because INSN entirely sets X. 145318334Speter 1454169689Skan "Entirely set" means set directly and not through a SUBREG, or 1455169689Skan ZERO_EXTRACT, so no trace of the old contents remains. 145618334Speter Likewise, REG_INC does not count. 145718334Speter 145818334Speter REG may be a hard or pseudo reg. Renumbering is not taken into account, 145918334Speter but for this use that makes no difference, since regs don't overlap 146018334Speter during their lifetimes. Therefore, this function may be used 146118334Speter at any time after deaths have been computed (in flow.c). 146218334Speter 146318334Speter If REG is a hard reg that occupies multiple machine registers, this 146418334Speter function will only return 1 if each of those registers will be replaced 146518334Speter by INSN. */ 146618334Speter 146718334Speterint 1468132718Skandead_or_set_p (rtx insn, rtx x) 146918334Speter{ 147090075Sobrien unsigned int regno, last_regno; 147190075Sobrien unsigned int i; 147218334Speter 147318334Speter /* Can't use cc0_rtx below since this file is used by genattrtab.c. */ 147418334Speter if (GET_CODE (x) == CC0) 147518334Speter return 1; 147618334Speter 1477169689Skan gcc_assert (REG_P (x)); 147818334Speter 147918334Speter regno = REGNO (x); 148018334Speter last_regno = (regno >= FIRST_PSEUDO_REGISTER ? regno 1481169689Skan : regno + hard_regno_nregs[regno][GET_MODE (x)] - 1); 148218334Speter 148318334Speter for (i = regno; i <= last_regno; i++) 148418334Speter if (! dead_or_set_regno_p (insn, i)) 148518334Speter return 0; 148618334Speter 148718334Speter return 1; 148818334Speter} 148918334Speter 1490169689Skan/* Return TRUE iff DEST is a register or subreg of a register and 1491169689Skan doesn't change the number of words of the inner register, and any 1492169689Skan part of the register is TEST_REGNO. */ 1493169689Skan 1494169689Skanstatic bool 1495169689Skancovers_regno_no_parallel_p (rtx dest, unsigned int test_regno) 1496169689Skan{ 1497169689Skan unsigned int regno, endregno; 1498169689Skan 1499169689Skan if (GET_CODE (dest) == SUBREG 1500169689Skan && (((GET_MODE_SIZE (GET_MODE (dest)) 1501169689Skan + UNITS_PER_WORD - 1) / UNITS_PER_WORD) 1502169689Skan == ((GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest))) 1503169689Skan + UNITS_PER_WORD - 1) / UNITS_PER_WORD))) 1504169689Skan dest = SUBREG_REG (dest); 1505169689Skan 1506169689Skan if (!REG_P (dest)) 1507169689Skan return false; 1508169689Skan 1509169689Skan regno = REGNO (dest); 1510169689Skan endregno = (regno >= FIRST_PSEUDO_REGISTER ? regno + 1 1511169689Skan : regno + hard_regno_nregs[regno][GET_MODE (dest)]); 1512169689Skan return (test_regno >= regno && test_regno < endregno); 1513169689Skan} 1514169689Skan 1515169689Skan/* Like covers_regno_no_parallel_p, but also handles PARALLELs where 1516169689Skan any member matches the covers_regno_no_parallel_p criteria. */ 1517169689Skan 1518169689Skanstatic bool 1519169689Skancovers_regno_p (rtx dest, unsigned int test_regno) 1520169689Skan{ 1521169689Skan if (GET_CODE (dest) == PARALLEL) 1522169689Skan { 1523169689Skan /* Some targets place small structures in registers for return 1524169689Skan values of functions, and those registers are wrapped in 1525169689Skan PARALLELs that we may see as the destination of a SET. */ 1526169689Skan int i; 1527169689Skan 1528169689Skan for (i = XVECLEN (dest, 0) - 1; i >= 0; i--) 1529169689Skan { 1530169689Skan rtx inner = XEXP (XVECEXP (dest, 0, i), 0); 1531169689Skan if (inner != NULL_RTX 1532169689Skan && covers_regno_no_parallel_p (inner, test_regno)) 1533169689Skan return true; 1534169689Skan } 1535169689Skan 1536169689Skan return false; 1537169689Skan } 1538169689Skan else 1539169689Skan return covers_regno_no_parallel_p (dest, test_regno); 1540169689Skan} 1541169689Skan 154218334Speter/* Utility function for dead_or_set_p to check an individual register. Also 154318334Speter called from flow.c. */ 154418334Speter 154518334Speterint 1546132718Skandead_or_set_regno_p (rtx insn, unsigned int test_regno) 154718334Speter{ 154890075Sobrien rtx pattern; 154918334Speter 155090075Sobrien /* See if there is a death note for something that includes TEST_REGNO. */ 155190075Sobrien if (find_regno_note (insn, REG_DEAD, test_regno)) 155290075Sobrien return 1; 155318334Speter 1554169689Skan if (CALL_P (insn) 155518334Speter && find_regno_fusage (insn, CLOBBER, test_regno)) 155618334Speter return 1; 155718334Speter 155890075Sobrien pattern = PATTERN (insn); 155990075Sobrien 156090075Sobrien if (GET_CODE (pattern) == COND_EXEC) 156190075Sobrien pattern = COND_EXEC_CODE (pattern); 156290075Sobrien 156390075Sobrien if (GET_CODE (pattern) == SET) 1564169689Skan return covers_regno_p (SET_DEST (pattern), test_regno); 156590075Sobrien else if (GET_CODE (pattern) == PARALLEL) 156618334Speter { 156790075Sobrien int i; 156818334Speter 156990075Sobrien for (i = XVECLEN (pattern, 0) - 1; i >= 0; i--) 157018334Speter { 157190075Sobrien rtx body = XVECEXP (pattern, 0, i); 157218334Speter 157390075Sobrien if (GET_CODE (body) == COND_EXEC) 157490075Sobrien body = COND_EXEC_CODE (body); 157590075Sobrien 1576169689Skan if ((GET_CODE (body) == SET || GET_CODE (body) == CLOBBER) 1577169689Skan && covers_regno_p (SET_DEST (body), test_regno)) 1578169689Skan return 1; 157918334Speter } 158018334Speter } 158118334Speter 158218334Speter return 0; 158318334Speter} 158418334Speter 158518334Speter/* Return the reg-note of kind KIND in insn INSN, if there is one. 158618334Speter If DATUM is nonzero, look for one whose datum is DATUM. */ 158718334Speter 158818334Speterrtx 1589132718Skanfind_reg_note (rtx insn, enum reg_note kind, rtx datum) 159018334Speter{ 159190075Sobrien rtx link; 159218334Speter 1593169689Skan gcc_assert (insn); 1594169689Skan 159550397Sobrien /* Ignore anything that is not an INSN, JUMP_INSN or CALL_INSN. */ 159690075Sobrien if (! INSN_P (insn)) 159750397Sobrien return 0; 1598169689Skan if (datum == 0) 1599169689Skan { 1600169689Skan for (link = REG_NOTES (insn); link; link = XEXP (link, 1)) 1601169689Skan if (REG_NOTE_KIND (link) == kind) 1602169689Skan return link; 1603169689Skan return 0; 1604169689Skan } 160550397Sobrien 160618334Speter for (link = REG_NOTES (insn); link; link = XEXP (link, 1)) 1607169689Skan if (REG_NOTE_KIND (link) == kind && datum == XEXP (link, 0)) 160818334Speter return link; 160918334Speter return 0; 161018334Speter} 161118334Speter 161218334Speter/* Return the reg-note of kind KIND in insn INSN which applies to register 161318334Speter number REGNO, if any. Return 0 if there is no such reg-note. Note that 161418334Speter the REGNO of this NOTE need not be REGNO if REGNO is a hard register; 161518334Speter it might be the case that the note overlaps REGNO. */ 161618334Speter 161718334Speterrtx 1618132718Skanfind_regno_note (rtx insn, enum reg_note kind, unsigned int regno) 161918334Speter{ 162090075Sobrien rtx link; 162118334Speter 162250397Sobrien /* Ignore anything that is not an INSN, JUMP_INSN or CALL_INSN. */ 162390075Sobrien if (! INSN_P (insn)) 162450397Sobrien return 0; 162550397Sobrien 162618334Speter for (link = REG_NOTES (insn); link; link = XEXP (link, 1)) 162718334Speter if (REG_NOTE_KIND (link) == kind 162818334Speter /* Verify that it is a register, so that scratch and MEM won't cause a 162918334Speter problem here. */ 1630169689Skan && REG_P (XEXP (link, 0)) 163118334Speter && REGNO (XEXP (link, 0)) <= regno 163218334Speter && ((REGNO (XEXP (link, 0)) 163318334Speter + (REGNO (XEXP (link, 0)) >= FIRST_PSEUDO_REGISTER ? 1 1634169689Skan : hard_regno_nregs[REGNO (XEXP (link, 0))] 1635169689Skan [GET_MODE (XEXP (link, 0))])) 163618334Speter > regno)) 163718334Speter return link; 163818334Speter return 0; 163918334Speter} 164018334Speter 164190075Sobrien/* Return a REG_EQUIV or REG_EQUAL note if insn has only a single set and 164290075Sobrien has such a note. */ 164390075Sobrien 164490075Sobrienrtx 1645132718Skanfind_reg_equal_equiv_note (rtx insn) 164690075Sobrien{ 1647132718Skan rtx link; 164890075Sobrien 1649132718Skan if (!INSN_P (insn)) 165090075Sobrien return 0; 1651132718Skan for (link = REG_NOTES (insn); link; link = XEXP (link, 1)) 1652132718Skan if (REG_NOTE_KIND (link) == REG_EQUAL 1653132718Skan || REG_NOTE_KIND (link) == REG_EQUIV) 1654132718Skan { 1655132718Skan if (single_set (insn) == 0) 1656132718Skan return 0; 1657132718Skan return link; 1658132718Skan } 1659132718Skan return NULL; 166090075Sobrien} 166190075Sobrien 166218334Speter/* Return true if DATUM, or any overlap of DATUM, of kind CODE is found 166318334Speter in the CALL_INSN_FUNCTION_USAGE information of INSN. */ 166418334Speter 166518334Speterint 1666132718Skanfind_reg_fusage (rtx insn, enum rtx_code code, rtx datum) 166718334Speter{ 166818334Speter /* If it's not a CALL_INSN, it can't possibly have a 166918334Speter CALL_INSN_FUNCTION_USAGE field, so don't bother checking. */ 1670169689Skan if (!CALL_P (insn)) 167118334Speter return 0; 167218334Speter 1673169689Skan gcc_assert (datum); 167418334Speter 1675169689Skan if (!REG_P (datum)) 167618334Speter { 167790075Sobrien rtx link; 167818334Speter 167918334Speter for (link = CALL_INSN_FUNCTION_USAGE (insn); 1680117395Skan link; 168118334Speter link = XEXP (link, 1)) 1682117395Skan if (GET_CODE (XEXP (link, 0)) == code 168390075Sobrien && rtx_equal_p (datum, XEXP (XEXP (link, 0), 0))) 1684117395Skan return 1; 168518334Speter } 168618334Speter else 168718334Speter { 168890075Sobrien unsigned int regno = REGNO (datum); 168918334Speter 169018334Speter /* CALL_INSN_FUNCTION_USAGE information cannot contain references 169118334Speter to pseudo registers, so don't bother checking. */ 169218334Speter 169318334Speter if (regno < FIRST_PSEUDO_REGISTER) 1694117395Skan { 169590075Sobrien unsigned int end_regno 1696169689Skan = regno + hard_regno_nregs[regno][GET_MODE (datum)]; 169790075Sobrien unsigned int i; 169818334Speter 169918334Speter for (i = regno; i < end_regno; i++) 170018334Speter if (find_regno_fusage (insn, code, i)) 170118334Speter return 1; 1702117395Skan } 170318334Speter } 170418334Speter 170518334Speter return 0; 170618334Speter} 170718334Speter 170818334Speter/* Return true if REGNO, or any overlap of REGNO, of kind CODE is found 170918334Speter in the CALL_INSN_FUNCTION_USAGE information of INSN. */ 171018334Speter 171118334Speterint 1712132718Skanfind_regno_fusage (rtx insn, enum rtx_code code, unsigned int regno) 171318334Speter{ 171490075Sobrien rtx link; 171518334Speter 171618334Speter /* CALL_INSN_FUNCTION_USAGE information cannot contain references 171718334Speter to pseudo registers, so don't bother checking. */ 171818334Speter 171918334Speter if (regno >= FIRST_PSEUDO_REGISTER 1720169689Skan || !CALL_P (insn) ) 172118334Speter return 0; 172218334Speter 172318334Speter for (link = CALL_INSN_FUNCTION_USAGE (insn); link; link = XEXP (link, 1)) 172490075Sobrien { 172590075Sobrien unsigned int regnote; 172690075Sobrien rtx op, reg; 172718334Speter 172890075Sobrien if (GET_CODE (op = XEXP (link, 0)) == code 1729169689Skan && REG_P (reg = XEXP (op, 0)) 173090075Sobrien && (regnote = REGNO (reg)) <= regno 1731169689Skan && regnote + hard_regno_nregs[regnote][GET_MODE (reg)] > regno) 173290075Sobrien return 1; 173390075Sobrien } 173418334Speter 173518334Speter return 0; 173618334Speter} 173796263Sobrien 173896263Sobrien/* Return true if INSN is a call to a pure function. */ 173996263Sobrien 174096263Sobrienint 1741132718Skanpure_call_p (rtx insn) 174296263Sobrien{ 174396263Sobrien rtx link; 174496263Sobrien 1745169689Skan if (!CALL_P (insn) || ! CONST_OR_PURE_CALL_P (insn)) 174696263Sobrien return 0; 174796263Sobrien 174896263Sobrien /* Look for the note that differentiates const and pure functions. */ 174996263Sobrien for (link = CALL_INSN_FUNCTION_USAGE (insn); link; link = XEXP (link, 1)) 175096263Sobrien { 175196263Sobrien rtx u, m; 175296263Sobrien 175396263Sobrien if (GET_CODE (u = XEXP (link, 0)) == USE 1754169689Skan && MEM_P (m = XEXP (u, 0)) && GET_MODE (m) == BLKmode 175596263Sobrien && GET_CODE (XEXP (m, 0)) == SCRATCH) 175696263Sobrien return 1; 175796263Sobrien } 175896263Sobrien 175996263Sobrien return 0; 176096263Sobrien} 176118334Speter 176218334Speter/* Remove register note NOTE from the REG_NOTES of INSN. */ 176318334Speter 176418334Spetervoid 1765132718Skanremove_note (rtx insn, rtx note) 176618334Speter{ 176790075Sobrien rtx link; 176818334Speter 176990075Sobrien if (note == NULL_RTX) 177090075Sobrien return; 177190075Sobrien 177218334Speter if (REG_NOTES (insn) == note) 177318334Speter { 177418334Speter REG_NOTES (insn) = XEXP (note, 1); 177518334Speter return; 177618334Speter } 177718334Speter 177818334Speter for (link = REG_NOTES (insn); link; link = XEXP (link, 1)) 177918334Speter if (XEXP (link, 1) == note) 178018334Speter { 178118334Speter XEXP (link, 1) = XEXP (note, 1); 178218334Speter return; 178318334Speter } 178418334Speter 1785169689Skan gcc_unreachable (); 178618334Speter} 178752284Sobrien 178890075Sobrien/* Search LISTP (an EXPR_LIST) for an entry whose first operand is NODE and 178990075Sobrien return 1 if it is found. A simple equality test is used to determine if 179090075Sobrien NODE matches. */ 179152284Sobrien 179290075Sobrienint 1793132718Skanin_expr_list_p (rtx listp, rtx node) 179490075Sobrien{ 179590075Sobrien rtx x; 179652284Sobrien 179790075Sobrien for (x = listp; x; x = XEXP (x, 1)) 179890075Sobrien if (node == XEXP (x, 0)) 179990075Sobrien return 1; 180090075Sobrien 180190075Sobrien return 0; 180290075Sobrien} 180390075Sobrien 180490075Sobrien/* Search LISTP (an EXPR_LIST) for an entry whose first operand is NODE and 180590075Sobrien remove that entry from the list if it is found. 180690075Sobrien 180790075Sobrien A simple equality test is used to determine if NODE matches. */ 180890075Sobrien 180952284Sobrienvoid 1810132718Skanremove_node_from_expr_list (rtx node, rtx *listp) 181152284Sobrien{ 181252284Sobrien rtx temp = *listp; 181352284Sobrien rtx prev = NULL_RTX; 181452284Sobrien 181552284Sobrien while (temp) 181652284Sobrien { 181752284Sobrien if (node == XEXP (temp, 0)) 181852284Sobrien { 181952284Sobrien /* Splice the node out of the list. */ 182052284Sobrien if (prev) 182152284Sobrien XEXP (prev, 1) = XEXP (temp, 1); 182252284Sobrien else 182352284Sobrien *listp = XEXP (temp, 1); 182452284Sobrien 182552284Sobrien return; 182652284Sobrien } 182790075Sobrien 182890075Sobrien prev = temp; 182952284Sobrien temp = XEXP (temp, 1); 183052284Sobrien } 183152284Sobrien} 183218334Speter 183318334Speter/* Nonzero if X contains any volatile instructions. These are instructions 183418334Speter which may cause unpredictable machine state instructions, and thus no 183518334Speter instructions should be moved or combined across them. This includes 183618334Speter only volatile asms and UNSPEC_VOLATILE instructions. */ 183718334Speter 183818334Speterint 1839132718Skanvolatile_insn_p (rtx x) 184018334Speter{ 184190075Sobrien RTX_CODE code; 184218334Speter 184318334Speter code = GET_CODE (x); 184418334Speter switch (code) 184518334Speter { 184618334Speter case LABEL_REF: 184718334Speter case SYMBOL_REF: 184818334Speter case CONST_INT: 184918334Speter case CONST: 185018334Speter case CONST_DOUBLE: 185196263Sobrien case CONST_VECTOR: 185218334Speter case CC0: 185318334Speter case PC: 185418334Speter case REG: 185518334Speter case SCRATCH: 185618334Speter case CLOBBER: 185718334Speter case ADDR_VEC: 185818334Speter case ADDR_DIFF_VEC: 185918334Speter case CALL: 186018334Speter case MEM: 186118334Speter return 0; 186218334Speter 186318334Speter case UNSPEC_VOLATILE: 186418334Speter /* case TRAP_IF: This isn't clear yet. */ 186518334Speter return 1; 186618334Speter 1867110611Skan case ASM_INPUT: 186818334Speter case ASM_OPERANDS: 186918334Speter if (MEM_VOLATILE_P (x)) 187018334Speter return 1; 187150397Sobrien 187250397Sobrien default: 187350397Sobrien break; 187418334Speter } 187518334Speter 187618334Speter /* Recursively scan the operands of this expression. */ 187718334Speter 187818334Speter { 187990075Sobrien const char *fmt = GET_RTX_FORMAT (code); 188090075Sobrien int i; 1881117395Skan 188218334Speter for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) 188318334Speter { 188418334Speter if (fmt[i] == 'e') 188518334Speter { 188618334Speter if (volatile_insn_p (XEXP (x, i))) 188718334Speter return 1; 188818334Speter } 188990075Sobrien else if (fmt[i] == 'E') 189018334Speter { 189190075Sobrien int j; 189218334Speter for (j = 0; j < XVECLEN (x, i); j++) 189318334Speter if (volatile_insn_p (XVECEXP (x, i, j))) 189418334Speter return 1; 189518334Speter } 189618334Speter } 189718334Speter } 189818334Speter return 0; 189918334Speter} 190018334Speter 190118334Speter/* Nonzero if X contains any volatile memory references 190218334Speter UNSPEC_VOLATILE operations or volatile ASM_OPERANDS expressions. */ 190318334Speter 190418334Speterint 1905132718Skanvolatile_refs_p (rtx x) 190618334Speter{ 190790075Sobrien RTX_CODE code; 190818334Speter 190918334Speter code = GET_CODE (x); 191018334Speter switch (code) 191118334Speter { 191218334Speter case LABEL_REF: 191318334Speter case SYMBOL_REF: 191418334Speter case CONST_INT: 191518334Speter case CONST: 191618334Speter case CONST_DOUBLE: 191796263Sobrien case CONST_VECTOR: 191818334Speter case CC0: 191918334Speter case PC: 192018334Speter case REG: 192118334Speter case SCRATCH: 192218334Speter case CLOBBER: 192318334Speter case ADDR_VEC: 192418334Speter case ADDR_DIFF_VEC: 192518334Speter return 0; 192618334Speter 192718334Speter case UNSPEC_VOLATILE: 192818334Speter return 1; 192918334Speter 193018334Speter case MEM: 1931110611Skan case ASM_INPUT: 193218334Speter case ASM_OPERANDS: 193318334Speter if (MEM_VOLATILE_P (x)) 193418334Speter return 1; 193550397Sobrien 193650397Sobrien default: 193750397Sobrien break; 193818334Speter } 193918334Speter 194018334Speter /* Recursively scan the operands of this expression. */ 194118334Speter 194218334Speter { 194390075Sobrien const char *fmt = GET_RTX_FORMAT (code); 194490075Sobrien int i; 1945117395Skan 194618334Speter for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) 194718334Speter { 194818334Speter if (fmt[i] == 'e') 194918334Speter { 195018334Speter if (volatile_refs_p (XEXP (x, i))) 195118334Speter return 1; 195218334Speter } 195390075Sobrien else if (fmt[i] == 'E') 195418334Speter { 195590075Sobrien int j; 195618334Speter for (j = 0; j < XVECLEN (x, i); j++) 195718334Speter if (volatile_refs_p (XVECEXP (x, i, j))) 195818334Speter return 1; 195918334Speter } 196018334Speter } 196118334Speter } 196218334Speter return 0; 196318334Speter} 196418334Speter 196518334Speter/* Similar to above, except that it also rejects register pre- and post- 196618334Speter incrementing. */ 196718334Speter 196818334Speterint 1969132718Skanside_effects_p (rtx x) 197018334Speter{ 197190075Sobrien RTX_CODE code; 197218334Speter 197318334Speter code = GET_CODE (x); 197418334Speter switch (code) 197518334Speter { 197618334Speter case LABEL_REF: 197718334Speter case SYMBOL_REF: 197818334Speter case CONST_INT: 197918334Speter case CONST: 198018334Speter case CONST_DOUBLE: 198196263Sobrien case CONST_VECTOR: 198218334Speter case CC0: 198318334Speter case PC: 198418334Speter case REG: 198518334Speter case SCRATCH: 198618334Speter case ADDR_VEC: 198718334Speter case ADDR_DIFF_VEC: 198818334Speter return 0; 198918334Speter 199018334Speter case CLOBBER: 199118334Speter /* Reject CLOBBER with a non-VOID mode. These are made by combine.c 199218334Speter when some combination can't be done. If we see one, don't think 199318334Speter that we can simplify the expression. */ 199418334Speter return (GET_MODE (x) != VOIDmode); 199518334Speter 199618334Speter case PRE_INC: 199718334Speter case PRE_DEC: 199818334Speter case POST_INC: 199918334Speter case POST_DEC: 200090075Sobrien case PRE_MODIFY: 200190075Sobrien case POST_MODIFY: 200218334Speter case CALL: 200318334Speter case UNSPEC_VOLATILE: 200418334Speter /* case TRAP_IF: This isn't clear yet. */ 200518334Speter return 1; 200618334Speter 200718334Speter case MEM: 2008110611Skan case ASM_INPUT: 200918334Speter case ASM_OPERANDS: 201018334Speter if (MEM_VOLATILE_P (x)) 201118334Speter return 1; 201250397Sobrien 201350397Sobrien default: 201450397Sobrien break; 201518334Speter } 201618334Speter 201718334Speter /* Recursively scan the operands of this expression. */ 201818334Speter 201918334Speter { 202090075Sobrien const char *fmt = GET_RTX_FORMAT (code); 202190075Sobrien int i; 2022117395Skan 202318334Speter for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) 202418334Speter { 202518334Speter if (fmt[i] == 'e') 202618334Speter { 202718334Speter if (side_effects_p (XEXP (x, i))) 202818334Speter return 1; 202918334Speter } 203090075Sobrien else if (fmt[i] == 'E') 203118334Speter { 203290075Sobrien int j; 203318334Speter for (j = 0; j < XVECLEN (x, i); j++) 203418334Speter if (side_effects_p (XVECEXP (x, i, j))) 203518334Speter return 1; 203618334Speter } 203718334Speter } 203818334Speter } 203918334Speter return 0; 204018334Speter} 204118334Speter 2042169689Skanenum may_trap_p_flags 2043169689Skan{ 2044169689Skan MTP_UNALIGNED_MEMS = 1, 2045169689Skan MTP_AFTER_MOVE = 2 2046169689Skan}; 2047169689Skan/* Return nonzero if evaluating rtx X might cause a trap. 2048169689Skan (FLAGS & MTP_UNALIGNED_MEMS) controls whether nonzero is returned for 2049169689Skan unaligned memory accesses on strict alignment machines. If 2050169689Skan (FLAGS & AFTER_MOVE) is true, returns nonzero even in case the expression 2051169689Skan cannot trap at its current location, but it might become trapping if moved 2052169689Skan elsewhere. */ 205318334Speter 2054169689Skanstatic int 2055169689Skanmay_trap_p_1 (rtx x, unsigned flags) 205618334Speter{ 205718334Speter int i; 205818334Speter enum rtx_code code; 205990075Sobrien const char *fmt; 2060169689Skan bool unaligned_mems = (flags & MTP_UNALIGNED_MEMS) != 0; 206118334Speter 206218334Speter if (x == 0) 206318334Speter return 0; 206418334Speter code = GET_CODE (x); 206518334Speter switch (code) 206618334Speter { 206718334Speter /* Handle these cases quickly. */ 206818334Speter case CONST_INT: 206918334Speter case CONST_DOUBLE: 207096263Sobrien case CONST_VECTOR: 207118334Speter case SYMBOL_REF: 207218334Speter case LABEL_REF: 207318334Speter case CONST: 207418334Speter case PC: 207518334Speter case CC0: 207618334Speter case REG: 207718334Speter case SCRATCH: 207818334Speter return 0; 207918334Speter 208090075Sobrien case ASM_INPUT: 208118334Speter case UNSPEC_VOLATILE: 208218334Speter case TRAP_IF: 208318334Speter return 1; 208418334Speter 208590075Sobrien case ASM_OPERANDS: 208690075Sobrien return MEM_VOLATILE_P (x); 208790075Sobrien 208818334Speter /* Memory ref can trap unless it's a static var or a stack slot. */ 208918334Speter case MEM: 2090169689Skan if (/* MEM_NOTRAP_P only relates to the actual position of the memory 2091169689Skan reference; moving it out of condition might cause its address 2092169689Skan become invalid. */ 2093169689Skan !(flags & MTP_AFTER_MOVE) 2094169689Skan && MEM_NOTRAP_P (x) 2095169689Skan && (!STRICT_ALIGNMENT || !unaligned_mems)) 2096117395Skan return 0; 2097169689Skan return 2098169689Skan rtx_addr_can_trap_p_1 (XEXP (x, 0), GET_MODE (x), unaligned_mems); 209918334Speter 210018334Speter /* Division by a non-constant might trap. */ 210118334Speter case DIV: 210218334Speter case MOD: 210318334Speter case UDIV: 210418334Speter case UMOD: 2105117395Skan if (HONOR_SNANS (GET_MODE (x))) 2106117395Skan return 1; 2107169689Skan if (SCALAR_FLOAT_MODE_P (GET_MODE (x))) 2108169689Skan return flag_trapping_math; 2109169689Skan if (!CONSTANT_P (XEXP (x, 1)) || (XEXP (x, 1) == const0_rtx)) 211018334Speter return 1; 211150397Sobrien break; 211250397Sobrien 211318334Speter case EXPR_LIST: 211418334Speter /* An EXPR_LIST is used to represent a function call. This 211518334Speter certainly may trap. */ 211618334Speter return 1; 211750397Sobrien 211890075Sobrien case GE: 211990075Sobrien case GT: 212090075Sobrien case LE: 212190075Sobrien case LT: 2122169689Skan case LTGT: 212390075Sobrien case COMPARE: 212490075Sobrien /* Some floating point comparisons may trap. */ 2125117395Skan if (!flag_trapping_math) 2126117395Skan break; 212790075Sobrien /* ??? There is no machine independent way to check for tests that trap 212890075Sobrien when COMPARE is used, though many targets do make this distinction. 212990075Sobrien For instance, sparc uses CCFPE for compares which generate exceptions 213090075Sobrien and CCFP for compares which do not generate exceptions. */ 2131117395Skan if (HONOR_NANS (GET_MODE (x))) 213290075Sobrien return 1; 213390075Sobrien /* But often the compare has some CC mode, so check operand 213490075Sobrien modes as well. */ 2135117395Skan if (HONOR_NANS (GET_MODE (XEXP (x, 0))) 2136117395Skan || HONOR_NANS (GET_MODE (XEXP (x, 1)))) 213790075Sobrien return 1; 213890075Sobrien break; 213990075Sobrien 2140117395Skan case EQ: 2141117395Skan case NE: 2142117395Skan if (HONOR_SNANS (GET_MODE (x))) 2143117395Skan return 1; 2144117395Skan /* Often comparison is CC mode, so check operand modes. */ 2145117395Skan if (HONOR_SNANS (GET_MODE (XEXP (x, 0))) 2146117395Skan || HONOR_SNANS (GET_MODE (XEXP (x, 1)))) 2147117395Skan return 1; 2148117395Skan break; 2149117395Skan 2150117395Skan case FIX: 2151117395Skan /* Conversion of floating point might trap. */ 2152117395Skan if (flag_trapping_math && HONOR_NANS (GET_MODE (XEXP (x, 0)))) 2153117395Skan return 1; 2154117395Skan break; 2155117395Skan 215690075Sobrien case NEG: 215790075Sobrien case ABS: 2158169689Skan case SUBREG: 215990075Sobrien /* These operations don't trap even with floating point. */ 216090075Sobrien break; 216190075Sobrien 216218334Speter default: 216318334Speter /* Any floating arithmetic may trap. */ 2164169689Skan if (SCALAR_FLOAT_MODE_P (GET_MODE (x)) 2165117395Skan && flag_trapping_math) 216618334Speter return 1; 216718334Speter } 216818334Speter 216918334Speter fmt = GET_RTX_FORMAT (code); 217018334Speter for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) 217118334Speter { 217218334Speter if (fmt[i] == 'e') 217318334Speter { 2174169689Skan if (may_trap_p_1 (XEXP (x, i), flags)) 217518334Speter return 1; 217618334Speter } 217718334Speter else if (fmt[i] == 'E') 217818334Speter { 217990075Sobrien int j; 218018334Speter for (j = 0; j < XVECLEN (x, i); j++) 2181169689Skan if (may_trap_p_1 (XVECEXP (x, i, j), flags)) 218218334Speter return 1; 218318334Speter } 218418334Speter } 218518334Speter return 0; 218618334Speter} 2187169689Skan 2188169689Skan/* Return nonzero if evaluating rtx X might cause a trap. */ 2189169689Skan 2190169689Skanint 2191169689Skanmay_trap_p (rtx x) 2192169689Skan{ 2193169689Skan return may_trap_p_1 (x, 0); 2194169689Skan} 2195169689Skan 2196169689Skan/* Return nonzero if evaluating rtx X might cause a trap, when the expression 2197169689Skan is moved from its current location by some optimization. */ 2198169689Skan 2199169689Skanint 2200169689Skanmay_trap_after_code_motion_p (rtx x) 2201169689Skan{ 2202169689Skan return may_trap_p_1 (x, MTP_AFTER_MOVE); 2203169689Skan} 2204169689Skan 2205169689Skan/* Same as above, but additionally return nonzero if evaluating rtx X might 2206169689Skan cause a fault. We define a fault for the purpose of this function as a 2207169689Skan erroneous execution condition that cannot be encountered during the normal 2208169689Skan execution of a valid program; the typical example is an unaligned memory 2209169689Skan access on a strict alignment machine. The compiler guarantees that it 2210169689Skan doesn't generate code that will fault from a valid program, but this 2211169689Skan guarantee doesn't mean anything for individual instructions. Consider 2212169689Skan the following example: 2213169689Skan 2214169689Skan struct S { int d; union { char *cp; int *ip; }; }; 2215169689Skan 2216169689Skan int foo(struct S *s) 2217169689Skan { 2218169689Skan if (s->d == 1) 2219169689Skan return *s->ip; 2220169689Skan else 2221169689Skan return *s->cp; 2222169689Skan } 2223169689Skan 2224169689Skan on a strict alignment machine. In a valid program, foo will never be 2225169689Skan invoked on a structure for which d is equal to 1 and the underlying 2226169689Skan unique field of the union not aligned on a 4-byte boundary, but the 2227169689Skan expression *s->ip might cause a fault if considered individually. 2228169689Skan 2229169689Skan At the RTL level, potentially problematic expressions will almost always 2230169689Skan verify may_trap_p; for example, the above dereference can be emitted as 2231169689Skan (mem:SI (reg:P)) and this expression is may_trap_p for a generic register. 2232169689Skan However, suppose that foo is inlined in a caller that causes s->cp to 2233169689Skan point to a local character variable and guarantees that s->d is not set 2234169689Skan to 1; foo may have been effectively translated into pseudo-RTL as: 2235169689Skan 2236169689Skan if ((reg:SI) == 1) 2237169689Skan (set (reg:SI) (mem:SI (%fp - 7))) 2238169689Skan else 2239169689Skan (set (reg:QI) (mem:QI (%fp - 7))) 2240169689Skan 2241169689Skan Now (mem:SI (%fp - 7)) is considered as not may_trap_p since it is a 2242169689Skan memory reference to a stack slot, but it will certainly cause a fault 2243169689Skan on a strict alignment machine. */ 2244169689Skan 2245169689Skanint 2246169689Skanmay_trap_or_fault_p (rtx x) 2247169689Skan{ 2248169689Skan return may_trap_p_1 (x, MTP_UNALIGNED_MEMS); 2249169689Skan} 225018334Speter 225118334Speter/* Return nonzero if X contains a comparison that is not either EQ or NE, 225218334Speter i.e., an inequality. */ 225318334Speter 225418334Speterint 2255132718Skaninequality_comparisons_p (rtx x) 225618334Speter{ 225790075Sobrien const char *fmt; 225890075Sobrien int len, i; 225990075Sobrien enum rtx_code code = GET_CODE (x); 226018334Speter 226118334Speter switch (code) 226218334Speter { 226318334Speter case REG: 226418334Speter case SCRATCH: 226518334Speter case PC: 226618334Speter case CC0: 226718334Speter case CONST_INT: 226818334Speter case CONST_DOUBLE: 226996263Sobrien case CONST_VECTOR: 227018334Speter case CONST: 227118334Speter case LABEL_REF: 227218334Speter case SYMBOL_REF: 227318334Speter return 0; 227418334Speter 227518334Speter case LT: 227618334Speter case LTU: 227718334Speter case GT: 227818334Speter case GTU: 227918334Speter case LE: 228018334Speter case LEU: 228118334Speter case GE: 228218334Speter case GEU: 228318334Speter return 1; 2284117395Skan 228550397Sobrien default: 228650397Sobrien break; 228718334Speter } 228818334Speter 228918334Speter len = GET_RTX_LENGTH (code); 229018334Speter fmt = GET_RTX_FORMAT (code); 229118334Speter 229218334Speter for (i = 0; i < len; i++) 229318334Speter { 229418334Speter if (fmt[i] == 'e') 229518334Speter { 229618334Speter if (inequality_comparisons_p (XEXP (x, i))) 229718334Speter return 1; 229818334Speter } 229918334Speter else if (fmt[i] == 'E') 230018334Speter { 230190075Sobrien int j; 230218334Speter for (j = XVECLEN (x, i) - 1; j >= 0; j--) 230318334Speter if (inequality_comparisons_p (XVECEXP (x, i, j))) 230418334Speter return 1; 230518334Speter } 230618334Speter } 2307117395Skan 230818334Speter return 0; 230918334Speter} 231018334Speter 231150397Sobrien/* Replace any occurrence of FROM in X with TO. The function does 231250397Sobrien not enter into CONST_DOUBLE for the replace. 231318334Speter 231418334Speter Note that copying is not done so X must not be shared unless all copies 231518334Speter are to be modified. */ 231618334Speter 231718334Speterrtx 2318132718Skanreplace_rtx (rtx x, rtx from, rtx to) 231918334Speter{ 232090075Sobrien int i, j; 232190075Sobrien const char *fmt; 232218334Speter 232350397Sobrien /* The following prevents loops occurrence when we change MEM in 232490075Sobrien CONST_DOUBLE onto the same CONST_DOUBLE. */ 232550397Sobrien if (x != 0 && GET_CODE (x) == CONST_DOUBLE) 232650397Sobrien return x; 232750397Sobrien 232818334Speter if (x == from) 232918334Speter return to; 233018334Speter 233118334Speter /* Allow this function to make replacements in EXPR_LISTs. */ 233218334Speter if (x == 0) 233318334Speter return 0; 233418334Speter 233596263Sobrien if (GET_CODE (x) == SUBREG) 233696263Sobrien { 233796263Sobrien rtx new = replace_rtx (SUBREG_REG (x), from, to); 233896263Sobrien 233996263Sobrien if (GET_CODE (new) == CONST_INT) 234096263Sobrien { 234196263Sobrien x = simplify_subreg (GET_MODE (x), new, 234296263Sobrien GET_MODE (SUBREG_REG (x)), 234396263Sobrien SUBREG_BYTE (x)); 2344169689Skan gcc_assert (x); 234596263Sobrien } 234696263Sobrien else 234796263Sobrien SUBREG_REG (x) = new; 234896263Sobrien 234996263Sobrien return x; 235096263Sobrien } 235196263Sobrien else if (GET_CODE (x) == ZERO_EXTEND) 235296263Sobrien { 235396263Sobrien rtx new = replace_rtx (XEXP (x, 0), from, to); 235496263Sobrien 235596263Sobrien if (GET_CODE (new) == CONST_INT) 235696263Sobrien { 235796263Sobrien x = simplify_unary_operation (ZERO_EXTEND, GET_MODE (x), 235896263Sobrien new, GET_MODE (XEXP (x, 0))); 2359169689Skan gcc_assert (x); 236096263Sobrien } 236196263Sobrien else 236296263Sobrien XEXP (x, 0) = new; 236396263Sobrien 236496263Sobrien return x; 236596263Sobrien } 236696263Sobrien 236718334Speter fmt = GET_RTX_FORMAT (GET_CODE (x)); 236818334Speter for (i = GET_RTX_LENGTH (GET_CODE (x)) - 1; i >= 0; i--) 236918334Speter { 237018334Speter if (fmt[i] == 'e') 237118334Speter XEXP (x, i) = replace_rtx (XEXP (x, i), from, to); 237218334Speter else if (fmt[i] == 'E') 237318334Speter for (j = XVECLEN (x, i) - 1; j >= 0; j--) 237418334Speter XVECEXP (x, i, j) = replace_rtx (XVECEXP (x, i, j), from, to); 237518334Speter } 237618334Speter 237718334Speter return x; 2378117395Skan} 237918334Speter 2380132718Skan/* Replace occurrences of the old label in *X with the new one. 2381132718Skan DATA is a REPLACE_LABEL_DATA containing the old and new labels. */ 2382132718Skan 2383132718Skanint 2384132718Skanreplace_label (rtx *x, void *data) 2385132718Skan{ 2386132718Skan rtx l = *x; 2387132718Skan rtx old_label = ((replace_label_data *) data)->r1; 2388132718Skan rtx new_label = ((replace_label_data *) data)->r2; 2389132718Skan bool update_label_nuses = ((replace_label_data *) data)->update_label_nuses; 2390132718Skan 2391132718Skan if (l == NULL_RTX) 2392132718Skan return 0; 2393132718Skan 2394132718Skan if (GET_CODE (l) == SYMBOL_REF 2395132718Skan && CONSTANT_POOL_ADDRESS_P (l)) 2396132718Skan { 2397132718Skan rtx c = get_pool_constant (l); 2398132718Skan if (rtx_referenced_p (old_label, c)) 2399132718Skan { 2400132718Skan rtx new_c, new_l; 2401132718Skan replace_label_data *d = (replace_label_data *) data; 2402132718Skan 2403132718Skan /* Create a copy of constant C; replace the label inside 2404132718Skan but do not update LABEL_NUSES because uses in constant pool 2405132718Skan are not counted. */ 2406132718Skan new_c = copy_rtx (c); 2407132718Skan d->update_label_nuses = false; 2408132718Skan for_each_rtx (&new_c, replace_label, data); 2409132718Skan d->update_label_nuses = update_label_nuses; 2410132718Skan 2411132718Skan /* Add the new constant NEW_C to constant pool and replace 2412132718Skan the old reference to constant by new reference. */ 2413132718Skan new_l = XEXP (force_const_mem (get_pool_mode (l), new_c), 0); 2414132718Skan *x = replace_rtx (l, l, new_l); 2415132718Skan } 2416132718Skan return 0; 2417132718Skan } 2418132718Skan 2419132718Skan /* If this is a JUMP_INSN, then we also need to fix the JUMP_LABEL 2420132718Skan field. This is not handled by for_each_rtx because it doesn't 2421132718Skan handle unprinted ('0') fields. */ 2422169689Skan if (JUMP_P (l) && JUMP_LABEL (l) == old_label) 2423132718Skan JUMP_LABEL (l) = new_label; 2424132718Skan 2425132718Skan if ((GET_CODE (l) == LABEL_REF 2426132718Skan || GET_CODE (l) == INSN_LIST) 2427132718Skan && XEXP (l, 0) == old_label) 2428132718Skan { 2429132718Skan XEXP (l, 0) = new_label; 2430132718Skan if (update_label_nuses) 2431132718Skan { 2432132718Skan ++LABEL_NUSES (new_label); 2433132718Skan --LABEL_NUSES (old_label); 2434132718Skan } 2435132718Skan return 0; 2436132718Skan } 2437132718Skan 2438132718Skan return 0; 2439132718Skan} 2440132718Skan 2441132718Skan/* When *BODY is equal to X or X is directly referenced by *BODY 2442132718Skan return nonzero, thus FOR_EACH_RTX stops traversing and returns nonzero 2443132718Skan too, otherwise FOR_EACH_RTX continues traversing *BODY. */ 2444132718Skan 2445132718Skanstatic int 2446132718Skanrtx_referenced_p_1 (rtx *body, void *x) 2447132718Skan{ 2448132718Skan rtx y = (rtx) x; 2449132718Skan 2450132718Skan if (*body == NULL_RTX) 2451132718Skan return y == NULL_RTX; 2452132718Skan 2453132718Skan /* Return true if a label_ref *BODY refers to label Y. */ 2454169689Skan if (GET_CODE (*body) == LABEL_REF && LABEL_P (y)) 2455132718Skan return XEXP (*body, 0) == y; 2456132718Skan 2457132718Skan /* If *BODY is a reference to pool constant traverse the constant. */ 2458132718Skan if (GET_CODE (*body) == SYMBOL_REF 2459132718Skan && CONSTANT_POOL_ADDRESS_P (*body)) 2460132718Skan return rtx_referenced_p (y, get_pool_constant (*body)); 2461132718Skan 2462132718Skan /* By default, compare the RTL expressions. */ 2463132718Skan return rtx_equal_p (*body, y); 2464132718Skan} 2465132718Skan 2466132718Skan/* Return true if X is referenced in BODY. */ 2467132718Skan 2468132718Skanint 2469132718Skanrtx_referenced_p (rtx x, rtx body) 2470132718Skan{ 2471132718Skan return for_each_rtx (&body, rtx_referenced_p_1, x); 2472132718Skan} 2473132718Skan 2474132718Skan/* If INSN is a tablejump return true and store the label (before jump table) to 2475132718Skan *LABELP and the jump table to *TABLEP. LABELP and TABLEP may be NULL. */ 2476132718Skan 2477132718Skanbool 2478132718Skantablejump_p (rtx insn, rtx *labelp, rtx *tablep) 2479132718Skan{ 2480132718Skan rtx label, table; 2481132718Skan 2482169689Skan if (JUMP_P (insn) 2483132718Skan && (label = JUMP_LABEL (insn)) != NULL_RTX 2484132718Skan && (table = next_active_insn (label)) != NULL_RTX 2485169689Skan && JUMP_P (table) 2486132718Skan && (GET_CODE (PATTERN (table)) == ADDR_VEC 2487132718Skan || GET_CODE (PATTERN (table)) == ADDR_DIFF_VEC)) 2488132718Skan { 2489132718Skan if (labelp) 2490132718Skan *labelp = label; 2491132718Skan if (tablep) 2492132718Skan *tablep = table; 2493132718Skan return true; 2494132718Skan } 2495132718Skan return false; 2496132718Skan} 2497132718Skan 249890075Sobrien/* A subroutine of computed_jump_p, return 1 if X contains a REG or MEM or 249990075Sobrien constant that is not in the constant pool and not in the condition 250090075Sobrien of an IF_THEN_ELSE. */ 250150397Sobrien 250250397Sobrienstatic int 2503132718Skancomputed_jump_p_1 (rtx x) 250450397Sobrien{ 250550397Sobrien enum rtx_code code = GET_CODE (x); 250650397Sobrien int i, j; 250790075Sobrien const char *fmt; 250850397Sobrien 250950397Sobrien switch (code) 251050397Sobrien { 251150397Sobrien case LABEL_REF: 251250397Sobrien case PC: 251350397Sobrien return 0; 251450397Sobrien 251590075Sobrien case CONST: 251690075Sobrien case CONST_INT: 251790075Sobrien case CONST_DOUBLE: 251896263Sobrien case CONST_VECTOR: 251990075Sobrien case SYMBOL_REF: 252050397Sobrien case REG: 252150397Sobrien return 1; 252250397Sobrien 252350397Sobrien case MEM: 252450397Sobrien return ! (GET_CODE (XEXP (x, 0)) == SYMBOL_REF 252550397Sobrien && CONSTANT_POOL_ADDRESS_P (XEXP (x, 0))); 252650397Sobrien 252750397Sobrien case IF_THEN_ELSE: 252890075Sobrien return (computed_jump_p_1 (XEXP (x, 1)) 252990075Sobrien || computed_jump_p_1 (XEXP (x, 2))); 253050397Sobrien 253150397Sobrien default: 253250397Sobrien break; 253350397Sobrien } 253450397Sobrien 253550397Sobrien fmt = GET_RTX_FORMAT (code); 253650397Sobrien for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) 253750397Sobrien { 253850397Sobrien if (fmt[i] == 'e' 253990075Sobrien && computed_jump_p_1 (XEXP (x, i))) 254050397Sobrien return 1; 254150397Sobrien 254290075Sobrien else if (fmt[i] == 'E') 254350397Sobrien for (j = 0; j < XVECLEN (x, i); j++) 254490075Sobrien if (computed_jump_p_1 (XVECEXP (x, i, j))) 254550397Sobrien return 1; 254650397Sobrien } 254750397Sobrien 254850397Sobrien return 0; 254950397Sobrien} 255050397Sobrien 255150397Sobrien/* Return nonzero if INSN is an indirect jump (aka computed jump). 255250397Sobrien 255350397Sobrien Tablejumps and casesi insns are not considered indirect jumps; 255490075Sobrien we can recognize them by a (use (label_ref)). */ 255550397Sobrien 255650397Sobrienint 2557132718Skancomputed_jump_p (rtx insn) 255850397Sobrien{ 255950397Sobrien int i; 2560169689Skan if (JUMP_P (insn)) 256150397Sobrien { 256250397Sobrien rtx pat = PATTERN (insn); 256350397Sobrien 256490075Sobrien if (find_reg_note (insn, REG_LABEL, NULL_RTX)) 256590075Sobrien return 0; 256690075Sobrien else if (GET_CODE (pat) == PARALLEL) 256750397Sobrien { 256850397Sobrien int len = XVECLEN (pat, 0); 256950397Sobrien int has_use_labelref = 0; 257050397Sobrien 257150397Sobrien for (i = len - 1; i >= 0; i--) 257250397Sobrien if (GET_CODE (XVECEXP (pat, 0, i)) == USE 257350397Sobrien && (GET_CODE (XEXP (XVECEXP (pat, 0, i), 0)) 257450397Sobrien == LABEL_REF)) 257550397Sobrien has_use_labelref = 1; 257650397Sobrien 257750397Sobrien if (! has_use_labelref) 257850397Sobrien for (i = len - 1; i >= 0; i--) 257950397Sobrien if (GET_CODE (XVECEXP (pat, 0, i)) == SET 258050397Sobrien && SET_DEST (XVECEXP (pat, 0, i)) == pc_rtx 258190075Sobrien && computed_jump_p_1 (SET_SRC (XVECEXP (pat, 0, i)))) 258250397Sobrien return 1; 258350397Sobrien } 258450397Sobrien else if (GET_CODE (pat) == SET 258550397Sobrien && SET_DEST (pat) == pc_rtx 258690075Sobrien && computed_jump_p_1 (SET_SRC (pat))) 258750397Sobrien return 1; 258850397Sobrien } 258950397Sobrien return 0; 259050397Sobrien} 259152284Sobrien 2592169689Skan/* Optimized loop of for_each_rtx, trying to avoid useless recursive 2593169689Skan calls. Processes the subexpressions of EXP and passes them to F. */ 2594169689Skanstatic int 2595169689Skanfor_each_rtx_1 (rtx exp, int n, rtx_function f, void *data) 2596169689Skan{ 2597169689Skan int result, i, j; 2598169689Skan const char *format = GET_RTX_FORMAT (GET_CODE (exp)); 2599169689Skan rtx *x; 2600169689Skan 2601169689Skan for (; format[n] != '\0'; n++) 2602169689Skan { 2603169689Skan switch (format[n]) 2604169689Skan { 2605169689Skan case 'e': 2606169689Skan /* Call F on X. */ 2607169689Skan x = &XEXP (exp, n); 2608169689Skan result = (*f) (x, data); 2609169689Skan if (result == -1) 2610169689Skan /* Do not traverse sub-expressions. */ 2611169689Skan continue; 2612169689Skan else if (result != 0) 2613169689Skan /* Stop the traversal. */ 2614169689Skan return result; 2615169689Skan 2616169689Skan if (*x == NULL_RTX) 2617169689Skan /* There are no sub-expressions. */ 2618169689Skan continue; 2619169689Skan 2620169689Skan i = non_rtx_starting_operands[GET_CODE (*x)]; 2621169689Skan if (i >= 0) 2622169689Skan { 2623169689Skan result = for_each_rtx_1 (*x, i, f, data); 2624169689Skan if (result != 0) 2625169689Skan return result; 2626169689Skan } 2627169689Skan break; 2628169689Skan 2629169689Skan case 'V': 2630169689Skan case 'E': 2631169689Skan if (XVEC (exp, n) == 0) 2632169689Skan continue; 2633169689Skan for (j = 0; j < XVECLEN (exp, n); ++j) 2634169689Skan { 2635169689Skan /* Call F on X. */ 2636169689Skan x = &XVECEXP (exp, n, j); 2637169689Skan result = (*f) (x, data); 2638169689Skan if (result == -1) 2639169689Skan /* Do not traverse sub-expressions. */ 2640169689Skan continue; 2641169689Skan else if (result != 0) 2642169689Skan /* Stop the traversal. */ 2643169689Skan return result; 2644169689Skan 2645169689Skan if (*x == NULL_RTX) 2646169689Skan /* There are no sub-expressions. */ 2647169689Skan continue; 2648169689Skan 2649169689Skan i = non_rtx_starting_operands[GET_CODE (*x)]; 2650169689Skan if (i >= 0) 2651169689Skan { 2652169689Skan result = for_each_rtx_1 (*x, i, f, data); 2653169689Skan if (result != 0) 2654169689Skan return result; 2655169689Skan } 2656169689Skan } 2657169689Skan break; 2658169689Skan 2659169689Skan default: 2660169689Skan /* Nothing to do. */ 2661169689Skan break; 2662169689Skan } 2663169689Skan } 2664169689Skan 2665169689Skan return 0; 2666169689Skan} 2667169689Skan 266852284Sobrien/* Traverse X via depth-first search, calling F for each 266952284Sobrien sub-expression (including X itself). F is also passed the DATA. 267052284Sobrien If F returns -1, do not traverse sub-expressions, but continue 267152284Sobrien traversing the rest of the tree. If F ever returns any other 2672117395Skan nonzero value, stop the traversal, and return the value returned 267352284Sobrien by F. Otherwise, return 0. This function does not traverse inside 267452284Sobrien tree structure that contains RTX_EXPRs, or into sub-expressions 267552284Sobrien whose format code is `0' since it is not known whether or not those 267652284Sobrien codes are actually RTL. 267752284Sobrien 267852284Sobrien This routine is very general, and could (should?) be used to 267952284Sobrien implement many of the other routines in this file. */ 268052284Sobrien 268152284Sobrienint 2682132718Skanfor_each_rtx (rtx *x, rtx_function f, void *data) 268352284Sobrien{ 268452284Sobrien int result; 268552284Sobrien int i; 268652284Sobrien 268752284Sobrien /* Call F on X. */ 268890075Sobrien result = (*f) (x, data); 268952284Sobrien if (result == -1) 269052284Sobrien /* Do not traverse sub-expressions. */ 269152284Sobrien return 0; 269252284Sobrien else if (result != 0) 269352284Sobrien /* Stop the traversal. */ 269452284Sobrien return result; 269552284Sobrien 269652284Sobrien if (*x == NULL_RTX) 269752284Sobrien /* There are no sub-expressions. */ 269852284Sobrien return 0; 269952284Sobrien 2700169689Skan i = non_rtx_starting_operands[GET_CODE (*x)]; 2701169689Skan if (i < 0) 2702169689Skan return 0; 270352284Sobrien 2704169689Skan return for_each_rtx_1 (*x, i, f, data); 2705169689Skan} 270652284Sobrien 270752284Sobrien 270852284Sobrien/* Searches X for any reference to REGNO, returning the rtx of the 270952284Sobrien reference found if any. Otherwise, returns NULL_RTX. */ 271052284Sobrien 271152284Sobrienrtx 2712132718Skanregno_use_in (unsigned int regno, rtx x) 271352284Sobrien{ 271490075Sobrien const char *fmt; 271552284Sobrien int i, j; 271652284Sobrien rtx tem; 271752284Sobrien 2718169689Skan if (REG_P (x) && REGNO (x) == regno) 271952284Sobrien return x; 272052284Sobrien 272152284Sobrien fmt = GET_RTX_FORMAT (GET_CODE (x)); 272252284Sobrien for (i = GET_RTX_LENGTH (GET_CODE (x)) - 1; i >= 0; i--) 272352284Sobrien { 272452284Sobrien if (fmt[i] == 'e') 272552284Sobrien { 272652284Sobrien if ((tem = regno_use_in (regno, XEXP (x, i)))) 272752284Sobrien return tem; 272852284Sobrien } 272952284Sobrien else if (fmt[i] == 'E') 273052284Sobrien for (j = XVECLEN (x, i) - 1; j >= 0; j--) 273152284Sobrien if ((tem = regno_use_in (regno , XVECEXP (x, i, j)))) 273252284Sobrien return tem; 273352284Sobrien } 273452284Sobrien 273552284Sobrien return NULL_RTX; 273652284Sobrien} 273752284Sobrien 273890075Sobrien/* Return a value indicating whether OP, an operand of a commutative 273990075Sobrien operation, is preferred as the first or second operand. The higher 274090075Sobrien the value, the stronger the preference for being the first operand. 274190075Sobrien We use negative values to indicate a preference for the first operand 274290075Sobrien and positive values for the second operand. */ 274352284Sobrien 274490075Sobrienint 2745132718Skancommutative_operand_precedence (rtx op) 274690075Sobrien{ 2747169689Skan enum rtx_code code = GET_CODE (op); 2748169689Skan 274990075Sobrien /* Constants always come the second operand. Prefer "nice" constants. */ 2750169689Skan if (code == CONST_INT) 2751169689Skan return -7; 2752169689Skan if (code == CONST_DOUBLE) 2753169689Skan return -6; 2754169689Skan op = avoid_constant_pool_reference (op); 2755169689Skan code = GET_CODE (op); 275690075Sobrien 2757169689Skan switch (GET_RTX_CLASS (code)) 2758169689Skan { 2759169689Skan case RTX_CONST_OBJ: 2760169689Skan if (code == CONST_INT) 2761169689Skan return -5; 2762169689Skan if (code == CONST_DOUBLE) 2763169689Skan return -4; 2764169689Skan return -3; 276590075Sobrien 2766169689Skan case RTX_EXTRA: 2767169689Skan /* SUBREGs of objects should come second. */ 2768169689Skan if (code == SUBREG && OBJECT_P (SUBREG_REG (op))) 2769169689Skan return -2; 277090075Sobrien 2771169689Skan if (!CONSTANT_P (op)) 2772169689Skan return 0; 2773169689Skan else 2774169689Skan /* As for RTX_CONST_OBJ. */ 2775169689Skan return -3; 2776169689Skan 2777169689Skan case RTX_OBJ: 2778169689Skan /* Complex expressions should be the first, so decrease priority 2779169689Skan of objects. */ 2780169689Skan return -1; 2781169689Skan 2782169689Skan case RTX_COMM_ARITH: 2783169689Skan /* Prefer operands that are themselves commutative to be first. 2784169689Skan This helps to make things linear. In particular, 2785169689Skan (and (and (reg) (reg)) (not (reg))) is canonical. */ 2786169689Skan return 4; 2787169689Skan 2788169689Skan case RTX_BIN_ARITH: 2789169689Skan /* If only one operand is a binary expression, it will be the first 2790169689Skan operand. In particular, (plus (minus (reg) (reg)) (neg (reg))) 2791169689Skan is canonical, although it will usually be further simplified. */ 2792169689Skan return 2; 2793169689Skan 2794169689Skan case RTX_UNARY: 2795169689Skan /* Then prefer NEG and NOT. */ 2796169689Skan if (code == NEG || code == NOT) 2797169689Skan return 1; 2798169689Skan 2799169689Skan default: 2800169689Skan return 0; 2801169689Skan } 280290075Sobrien} 280390075Sobrien 280490075Sobrien/* Return 1 iff it is necessary to swap operands of commutative operation 280590075Sobrien in order to canonicalize expression. */ 280690075Sobrien 280790075Sobrienint 2808132718Skanswap_commutative_operands_p (rtx x, rtx y) 280990075Sobrien{ 281090075Sobrien return (commutative_operand_precedence (x) 281190075Sobrien < commutative_operand_precedence (y)); 281290075Sobrien} 281390075Sobrien 281452284Sobrien/* Return 1 if X is an autoincrement side effect and the register is 281552284Sobrien not the stack pointer. */ 281652284Sobrienint 2817132718Skanauto_inc_p (rtx x) 281852284Sobrien{ 281952284Sobrien switch (GET_CODE (x)) 282052284Sobrien { 282152284Sobrien case PRE_INC: 282252284Sobrien case POST_INC: 282352284Sobrien case PRE_DEC: 282452284Sobrien case POST_DEC: 282552284Sobrien case PRE_MODIFY: 282652284Sobrien case POST_MODIFY: 282752284Sobrien /* There are no REG_INC notes for SP. */ 282852284Sobrien if (XEXP (x, 0) != stack_pointer_rtx) 282952284Sobrien return 1; 283052284Sobrien default: 283152284Sobrien break; 283252284Sobrien } 283352284Sobrien return 0; 283452284Sobrien} 283570635Sobrien 2836132718Skan/* Return nonzero if IN contains a piece of rtl that has the address LOC. */ 283790075Sobrienint 2838132718Skanloc_mentioned_in_p (rtx *loc, rtx in) 283990075Sobrien{ 284090075Sobrien enum rtx_code code = GET_CODE (in); 284190075Sobrien const char *fmt = GET_RTX_FORMAT (code); 284290075Sobrien int i, j; 284390075Sobrien 284490075Sobrien for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) 284590075Sobrien { 2846169689Skan if (loc == &in->u.fld[i].rt_rtx) 284790075Sobrien return 1; 284890075Sobrien if (fmt[i] == 'e') 284990075Sobrien { 285090075Sobrien if (loc_mentioned_in_p (loc, XEXP (in, i))) 285190075Sobrien return 1; 285290075Sobrien } 285390075Sobrien else if (fmt[i] == 'E') 285490075Sobrien for (j = XVECLEN (in, i) - 1; j >= 0; j--) 285590075Sobrien if (loc_mentioned_in_p (loc, XVECEXP (in, i, j))) 285690075Sobrien return 1; 285790075Sobrien } 285890075Sobrien return 0; 285990075Sobrien} 286090075Sobrien 2861169689Skan/* Helper function for subreg_lsb. Given a subreg's OUTER_MODE, INNER_MODE, 2862169689Skan and SUBREG_BYTE, return the bit offset where the subreg begins 2863169689Skan (counting from the least significant bit of the operand). */ 286490075Sobrien 286590075Sobrienunsigned int 2866169689Skansubreg_lsb_1 (enum machine_mode outer_mode, 2867169689Skan enum machine_mode inner_mode, 2868169689Skan unsigned int subreg_byte) 286990075Sobrien{ 287090075Sobrien unsigned int bitpos; 287190075Sobrien unsigned int byte; 287290075Sobrien unsigned int word; 287390075Sobrien 287490075Sobrien /* A paradoxical subreg begins at bit position 0. */ 2875169689Skan if (GET_MODE_BITSIZE (outer_mode) > GET_MODE_BITSIZE (inner_mode)) 287690075Sobrien return 0; 287790075Sobrien 287890075Sobrien if (WORDS_BIG_ENDIAN != BYTES_BIG_ENDIAN) 287990075Sobrien /* If the subreg crosses a word boundary ensure that 288090075Sobrien it also begins and ends on a word boundary. */ 2881169689Skan gcc_assert (!((subreg_byte % UNITS_PER_WORD 2882169689Skan + GET_MODE_SIZE (outer_mode)) > UNITS_PER_WORD 2883169689Skan && (subreg_byte % UNITS_PER_WORD 2884169689Skan || GET_MODE_SIZE (outer_mode) % UNITS_PER_WORD))); 288590075Sobrien 288690075Sobrien if (WORDS_BIG_ENDIAN) 288790075Sobrien word = (GET_MODE_SIZE (inner_mode) 2888169689Skan - (subreg_byte + GET_MODE_SIZE (outer_mode))) / UNITS_PER_WORD; 288990075Sobrien else 2890169689Skan word = subreg_byte / UNITS_PER_WORD; 289190075Sobrien bitpos = word * BITS_PER_WORD; 289290075Sobrien 289390075Sobrien if (BYTES_BIG_ENDIAN) 289490075Sobrien byte = (GET_MODE_SIZE (inner_mode) 2895169689Skan - (subreg_byte + GET_MODE_SIZE (outer_mode))) % UNITS_PER_WORD; 289690075Sobrien else 2897169689Skan byte = subreg_byte % UNITS_PER_WORD; 289890075Sobrien bitpos += byte * BITS_PER_UNIT; 289990075Sobrien 290090075Sobrien return bitpos; 290190075Sobrien} 290290075Sobrien 2903169689Skan/* Given a subreg X, return the bit offset where the subreg begins 2904169689Skan (counting from the least significant bit of the reg). */ 2905169689Skan 2906169689Skanunsigned int 2907169689Skansubreg_lsb (rtx x) 2908169689Skan{ 2909169689Skan return subreg_lsb_1 (GET_MODE (x), GET_MODE (SUBREG_REG (x)), 2910169689Skan SUBREG_BYTE (x)); 2911169689Skan} 2912169689Skan 291390075Sobrien/* This function returns the regno offset of a subreg expression. 291490075Sobrien xregno - A regno of an inner hard subreg_reg (or what will become one). 291590075Sobrien xmode - The mode of xregno. 291690075Sobrien offset - The byte offset. 291790075Sobrien ymode - The mode of a top level SUBREG (or what may become one). 291890075Sobrien RETURN - The regno offset which would be used. */ 291990075Sobrienunsigned int 2920132718Skansubreg_regno_offset (unsigned int xregno, enum machine_mode xmode, 2921132718Skan unsigned int offset, enum machine_mode ymode) 292290075Sobrien{ 292390075Sobrien int nregs_xmode, nregs_ymode; 292490075Sobrien int mode_multiple, nregs_multiple; 292590075Sobrien int y_offset; 292690075Sobrien 2927169689Skan gcc_assert (xregno < FIRST_PSEUDO_REGISTER); 292890075Sobrien 2929169689Skan /* Adjust nregs_xmode to allow for 'holes'. */ 2930169689Skan if (HARD_REGNO_NREGS_HAS_PADDING (xregno, xmode)) 2931169689Skan nregs_xmode = HARD_REGNO_NREGS_WITH_PADDING (xregno, xmode); 2932169689Skan else 2933169689Skan nregs_xmode = hard_regno_nregs[xregno][xmode]; 2934169689Skan 2935169689Skan nregs_ymode = hard_regno_nregs[xregno][ymode]; 2936117395Skan 2937117395Skan /* If this is a big endian paradoxical subreg, which uses more actual 2938117395Skan hard registers than the original register, we must return a negative 2939117395Skan offset so that we find the proper highpart of the register. */ 2940117395Skan if (offset == 0 2941117395Skan && nregs_ymode > nregs_xmode 2942117395Skan && (GET_MODE_SIZE (ymode) > UNITS_PER_WORD 2943117395Skan ? WORDS_BIG_ENDIAN : BYTES_BIG_ENDIAN)) 2944117395Skan return nregs_xmode - nregs_ymode; 2945117395Skan 294690075Sobrien if (offset == 0 || nregs_xmode == nregs_ymode) 294790075Sobrien return 0; 2948117395Skan 2949169689Skan /* Size of ymode must not be greater than the size of xmode. */ 295090075Sobrien mode_multiple = GET_MODE_SIZE (xmode) / GET_MODE_SIZE (ymode); 2951169689Skan gcc_assert (mode_multiple != 0); 295290075Sobrien 295390075Sobrien y_offset = offset / GET_MODE_SIZE (ymode); 295490075Sobrien nregs_multiple = nregs_xmode / nregs_ymode; 295590075Sobrien return (y_offset / (mode_multiple / nregs_multiple)) * nregs_ymode; 295690075Sobrien} 295790075Sobrien 2958117395Skan/* This function returns true when the offset is representable via 2959117395Skan subreg_offset in the given regno. 2960117395Skan xregno - A regno of an inner hard subreg_reg (or what will become one). 2961117395Skan xmode - The mode of xregno. 2962117395Skan offset - The byte offset. 2963117395Skan ymode - The mode of a top level SUBREG (or what may become one). 2964169689Skan RETURN - Whether the offset is representable. */ 2965117395Skanbool 2966132718Skansubreg_offset_representable_p (unsigned int xregno, enum machine_mode xmode, 2967132718Skan unsigned int offset, enum machine_mode ymode) 2968117395Skan{ 2969117395Skan int nregs_xmode, nregs_ymode; 2970117395Skan int mode_multiple, nregs_multiple; 2971117395Skan int y_offset; 2972169689Skan int regsize_xmode, regsize_ymode; 2973117395Skan 2974169689Skan gcc_assert (xregno < FIRST_PSEUDO_REGISTER); 2975117395Skan 2976169689Skan /* If there are holes in a non-scalar mode in registers, we expect 2977169689Skan that it is made up of its units concatenated together. */ 2978169689Skan if (HARD_REGNO_NREGS_HAS_PADDING (xregno, xmode)) 2979169689Skan { 2980169689Skan enum machine_mode xmode_unit; 2981117395Skan 2982169689Skan nregs_xmode = HARD_REGNO_NREGS_WITH_PADDING (xregno, xmode); 2983169689Skan if (GET_MODE_INNER (xmode) == VOIDmode) 2984169689Skan xmode_unit = xmode; 2985169689Skan else 2986169689Skan xmode_unit = GET_MODE_INNER (xmode); 2987169689Skan gcc_assert (HARD_REGNO_NREGS_HAS_PADDING (xregno, xmode_unit)); 2988169689Skan gcc_assert (nregs_xmode 2989169689Skan == (GET_MODE_NUNITS (xmode) 2990169689Skan * HARD_REGNO_NREGS_WITH_PADDING (xregno, xmode_unit))); 2991169689Skan gcc_assert (hard_regno_nregs[xregno][xmode] 2992169689Skan == (hard_regno_nregs[xregno][xmode_unit] 2993169689Skan * GET_MODE_NUNITS (xmode))); 2994169689Skan 2995169689Skan /* You can only ask for a SUBREG of a value with holes in the middle 2996169689Skan if you don't cross the holes. (Such a SUBREG should be done by 2997169689Skan picking a different register class, or doing it in memory if 2998169689Skan necessary.) An example of a value with holes is XCmode on 32-bit 2999169689Skan x86 with -m128bit-long-double; it's represented in 6 32-bit registers, 3000169689Skan 3 for each part, but in memory it's two 128-bit parts. 3001169689Skan Padding is assumed to be at the end (not necessarily the 'high part') 3002169689Skan of each unit. */ 3003169689Skan if ((offset / GET_MODE_SIZE (xmode_unit) + 1 3004169689Skan < GET_MODE_NUNITS (xmode)) 3005169689Skan && (offset / GET_MODE_SIZE (xmode_unit) 3006169689Skan != ((offset + GET_MODE_SIZE (ymode) - 1) 3007169689Skan / GET_MODE_SIZE (xmode_unit)))) 3008169689Skan return false; 3009169689Skan } 3010169689Skan else 3011169689Skan nregs_xmode = hard_regno_nregs[xregno][xmode]; 3012169689Skan 3013169689Skan nregs_ymode = hard_regno_nregs[xregno][ymode]; 3014169689Skan 3015169689Skan /* Paradoxical subregs are otherwise valid. */ 3016117395Skan if (offset == 0 3017117395Skan && nregs_ymode > nregs_xmode 3018117395Skan && (GET_MODE_SIZE (ymode) > UNITS_PER_WORD 3019117395Skan ? WORDS_BIG_ENDIAN : BYTES_BIG_ENDIAN)) 3020117395Skan return true; 3021117395Skan 3022169689Skan /* If registers store different numbers of bits in the different 3023169689Skan modes, we cannot generally form this subreg. */ 3024169689Skan regsize_xmode = GET_MODE_SIZE (xmode) / nregs_xmode; 3025169689Skan regsize_ymode = GET_MODE_SIZE (ymode) / nregs_ymode; 3026169689Skan if (regsize_xmode > regsize_ymode && nregs_ymode > 1) 3027169689Skan return false; 3028169689Skan if (regsize_ymode > regsize_xmode && nregs_xmode > 1) 3029169689Skan return false; 3030169689Skan 3031169689Skan /* Lowpart subregs are otherwise valid. */ 3032117395Skan if (offset == subreg_lowpart_offset (ymode, xmode)) 3033117395Skan return true; 3034117395Skan 3035169689Skan /* This should always pass, otherwise we don't know how to verify 3036169689Skan the constraint. These conditions may be relaxed but 3037169689Skan subreg_regno_offset would need to be redesigned. */ 3038169689Skan gcc_assert ((GET_MODE_SIZE (xmode) % GET_MODE_SIZE (ymode)) == 0); 3039169689Skan gcc_assert ((nregs_xmode % nregs_ymode) == 0); 3040117395Skan 3041132718Skan /* The XMODE value can be seen as a vector of NREGS_XMODE 3042132718Skan values. The subreg must represent a lowpart of given field. 3043117395Skan Compute what field it is. */ 3044132718Skan offset -= subreg_lowpart_offset (ymode, 3045132718Skan mode_for_size (GET_MODE_BITSIZE (xmode) 3046132718Skan / nregs_xmode, 3047117395Skan MODE_INT, 0)); 3048117395Skan 3049169689Skan /* Size of ymode must not be greater than the size of xmode. */ 3050117395Skan mode_multiple = GET_MODE_SIZE (xmode) / GET_MODE_SIZE (ymode); 3051169689Skan gcc_assert (mode_multiple != 0); 3052117395Skan 3053117395Skan y_offset = offset / GET_MODE_SIZE (ymode); 3054117395Skan nregs_multiple = nregs_xmode / nregs_ymode; 3055169689Skan 3056169689Skan gcc_assert ((offset % GET_MODE_SIZE (ymode)) == 0); 3057169689Skan gcc_assert ((mode_multiple % nregs_multiple) == 0); 3058169689Skan 3059117395Skan return (!(y_offset % (mode_multiple / nregs_multiple))); 3060117395Skan} 3061117395Skan 306290075Sobrien/* Return the final regno that a subreg expression refers to. */ 3063117395Skanunsigned int 3064132718Skansubreg_regno (rtx x) 306590075Sobrien{ 306690075Sobrien unsigned int ret; 306790075Sobrien rtx subreg = SUBREG_REG (x); 306890075Sobrien int regno = REGNO (subreg); 306990075Sobrien 3070117395Skan ret = regno + subreg_regno_offset (regno, 3071117395Skan GET_MODE (subreg), 307290075Sobrien SUBREG_BYTE (x), 307390075Sobrien GET_MODE (x)); 307490075Sobrien return ret; 307590075Sobrien 307690075Sobrien} 307790075Sobrienstruct parms_set_data 307890075Sobrien{ 307990075Sobrien int nregs; 308090075Sobrien HARD_REG_SET regs; 308190075Sobrien}; 308290075Sobrien 308390075Sobrien/* Helper function for noticing stores to parameter registers. */ 308490075Sobrienstatic void 3085132718Skanparms_set (rtx x, rtx pat ATTRIBUTE_UNUSED, void *data) 308690075Sobrien{ 308790075Sobrien struct parms_set_data *d = data; 308890075Sobrien if (REG_P (x) && REGNO (x) < FIRST_PSEUDO_REGISTER 308990075Sobrien && TEST_HARD_REG_BIT (d->regs, REGNO (x))) 309090075Sobrien { 309190075Sobrien CLEAR_HARD_REG_BIT (d->regs, REGNO (x)); 309290075Sobrien d->nregs--; 309390075Sobrien } 309490075Sobrien} 309590075Sobrien 3096117395Skan/* Look backward for first parameter to be loaded. 3097169689Skan Note that loads of all parameters will not necessarily be 3098169689Skan found if CSE has eliminated some of them (e.g., an argument 3099169689Skan to the outer function is passed down as a parameter). 310090075Sobrien Do not skip BOUNDARY. */ 310190075Sobrienrtx 3102132718Skanfind_first_parameter_load (rtx call_insn, rtx boundary) 310390075Sobrien{ 310490075Sobrien struct parms_set_data parm; 3105169689Skan rtx p, before, first_set; 310690075Sobrien 310790075Sobrien /* Since different machines initialize their parameter registers 310890075Sobrien in different orders, assume nothing. Collect the set of all 310990075Sobrien parameter registers. */ 311090075Sobrien CLEAR_HARD_REG_SET (parm.regs); 311190075Sobrien parm.nregs = 0; 311290075Sobrien for (p = CALL_INSN_FUNCTION_USAGE (call_insn); p; p = XEXP (p, 1)) 311390075Sobrien if (GET_CODE (XEXP (p, 0)) == USE 3114169689Skan && REG_P (XEXP (XEXP (p, 0), 0))) 311590075Sobrien { 3116169689Skan gcc_assert (REGNO (XEXP (XEXP (p, 0), 0)) < FIRST_PSEUDO_REGISTER); 311790075Sobrien 311890075Sobrien /* We only care about registers which can hold function 311990075Sobrien arguments. */ 312090075Sobrien if (!FUNCTION_ARG_REGNO_P (REGNO (XEXP (XEXP (p, 0), 0)))) 312190075Sobrien continue; 312290075Sobrien 312390075Sobrien SET_HARD_REG_BIT (parm.regs, REGNO (XEXP (XEXP (p, 0), 0))); 312490075Sobrien parm.nregs++; 312590075Sobrien } 312690075Sobrien before = call_insn; 3127169689Skan first_set = call_insn; 312890075Sobrien 312990075Sobrien /* Search backward for the first set of a register in this set. */ 313090075Sobrien while (parm.nregs && before != boundary) 313190075Sobrien { 313290075Sobrien before = PREV_INSN (before); 313390075Sobrien 313490075Sobrien /* It is possible that some loads got CSEed from one call to 313590075Sobrien another. Stop in that case. */ 3136169689Skan if (CALL_P (before)) 313790075Sobrien break; 313890075Sobrien 313990075Sobrien /* Our caller needs either ensure that we will find all sets 314090075Sobrien (in case code has not been optimized yet), or take care 314190075Sobrien for possible labels in a way by setting boundary to preceding 314290075Sobrien CODE_LABEL. */ 3143169689Skan if (LABEL_P (before)) 314490075Sobrien { 3145169689Skan gcc_assert (before == boundary); 314690075Sobrien break; 314790075Sobrien } 314890075Sobrien 314990075Sobrien if (INSN_P (before)) 3150169689Skan { 3151169689Skan int nregs_old = parm.nregs; 3152169689Skan note_stores (PATTERN (before), parms_set, &parm); 3153169689Skan /* If we found something that did not set a parameter reg, 3154169689Skan we're done. Do not keep going, as that might result 3155169689Skan in hoisting an insn before the setting of a pseudo 3156169689Skan that is used by the hoisted insn. */ 3157169689Skan if (nregs_old != parm.nregs) 3158169689Skan first_set = before; 3159169689Skan else 3160169689Skan break; 3161169689Skan } 316290075Sobrien } 3163169689Skan return first_set; 316490075Sobrien} 3165117395Skan 3166132718Skan/* Return true if we should avoid inserting code between INSN and preceding 3167117395Skan call instruction. */ 3168117395Skan 3169117395Skanbool 3170132718Skankeep_with_call_p (rtx insn) 3171117395Skan{ 3172117395Skan rtx set; 3173117395Skan 3174117395Skan if (INSN_P (insn) && (set = single_set (insn)) != NULL) 3175117395Skan { 3176169689Skan if (REG_P (SET_DEST (set)) 3177117395Skan && REGNO (SET_DEST (set)) < FIRST_PSEUDO_REGISTER 3178117395Skan && fixed_regs[REGNO (SET_DEST (set))] 3179117395Skan && general_operand (SET_SRC (set), VOIDmode)) 3180117395Skan return true; 3181169689Skan if (REG_P (SET_SRC (set)) 3182117395Skan && FUNCTION_VALUE_REGNO_P (REGNO (SET_SRC (set))) 3183169689Skan && REG_P (SET_DEST (set)) 3184117395Skan && REGNO (SET_DEST (set)) >= FIRST_PSEUDO_REGISTER) 3185117395Skan return true; 3186117395Skan /* There may be a stack pop just after the call and before the store 3187117395Skan of the return register. Search for the actual store when deciding 3188117395Skan if we can break or not. */ 3189117395Skan if (SET_DEST (set) == stack_pointer_rtx) 3190117395Skan { 3191117395Skan rtx i2 = next_nonnote_insn (insn); 3192117395Skan if (i2 && keep_with_call_p (i2)) 3193117395Skan return true; 3194117395Skan } 3195117395Skan } 3196117395Skan return false; 3197117395Skan} 3198117395Skan 3199169689Skan/* Return true if LABEL is a target of JUMP_INSN. This applies only 3200169689Skan to non-complex jumps. That is, direct unconditional, conditional, 3201169689Skan and tablejumps, but not computed jumps or returns. It also does 3202169689Skan not apply to the fallthru case of a conditional jump. */ 3203117395Skan 3204169689Skanbool 3205169689Skanlabel_is_jump_target_p (rtx label, rtx jump_insn) 3206117395Skan{ 3207169689Skan rtx tmp = JUMP_LABEL (jump_insn); 3208117395Skan 3209169689Skan if (label == tmp) 3210117395Skan return true; 3211117395Skan 3212169689Skan if (tablejump_p (jump_insn, NULL, &tmp)) 3213169689Skan { 3214169689Skan rtvec vec = XVEC (PATTERN (tmp), 3215169689Skan GET_CODE (PATTERN (tmp)) == ADDR_DIFF_VEC); 3216169689Skan int i, veclen = GET_NUM_ELEM (vec); 3217117395Skan 3218169689Skan for (i = 0; i < veclen; ++i) 3219169689Skan if (XEXP (RTVEC_ELT (vec, i), 0) == label) 3220169689Skan return true; 3221169689Skan } 3222169689Skan 3223169689Skan return false; 3224169689Skan} 3225169689Skan 3226169689Skan 3227169689Skan/* Return an estimate of the cost of computing rtx X. 3228169689Skan One use is in cse, to decide which expression to keep in the hash table. 3229169689Skan Another is in rtl generation, to pick the cheapest way to multiply. 3230169689Skan Other uses like the latter are expected in the future. */ 3231169689Skan 3232169689Skanint 3233169689Skanrtx_cost (rtx x, enum rtx_code outer_code ATTRIBUTE_UNUSED) 3234169689Skan{ 3235169689Skan int i, j; 3236169689Skan enum rtx_code code; 3237169689Skan const char *fmt; 3238169689Skan int total; 3239169689Skan 3240169689Skan if (x == 0) 3241169689Skan return 0; 3242169689Skan 3243169689Skan /* Compute the default costs of certain things. 3244169689Skan Note that targetm.rtx_costs can override the defaults. */ 3245169689Skan 3246169689Skan code = GET_CODE (x); 3247169689Skan switch (code) 3248117395Skan { 3249169689Skan case MULT: 3250169689Skan total = COSTS_N_INSNS (5); 3251169689Skan break; 3252169689Skan case DIV: 3253169689Skan case UDIV: 3254169689Skan case MOD: 3255169689Skan case UMOD: 3256169689Skan total = COSTS_N_INSNS (7); 3257169689Skan break; 3258169689Skan case USE: 3259169689Skan /* Used in combine.c as a marker. */ 3260169689Skan total = 0; 3261169689Skan break; 3262169689Skan default: 3263169689Skan total = COSTS_N_INSNS (1); 3264117395Skan } 3265117395Skan 3266169689Skan switch (code) 3267169689Skan { 3268169689Skan case REG: 3269169689Skan return 0; 3270117395Skan 3271169689Skan case SUBREG: 3272169689Skan total = 0; 3273169689Skan /* If we can't tie these modes, make this expensive. The larger 3274169689Skan the mode, the more expensive it is. */ 3275169689Skan if (! MODES_TIEABLE_P (GET_MODE (x), GET_MODE (SUBREG_REG (x)))) 3276169689Skan return COSTS_N_INSNS (2 3277169689Skan + GET_MODE_SIZE (GET_MODE (x)) / UNITS_PER_WORD); 3278169689Skan break; 3279117395Skan 3280169689Skan default: 3281169689Skan if (targetm.rtx_costs (x, code, outer_code, &total)) 3282169689Skan return total; 3283169689Skan break; 3284169689Skan } 3285117395Skan 3286169689Skan /* Sum the costs of the sub-rtx's, plus cost of this operation, 3287169689Skan which is already in total. */ 3288169689Skan 3289169689Skan fmt = GET_RTX_FORMAT (code); 3290169689Skan for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) 3291169689Skan if (fmt[i] == 'e') 3292169689Skan total += rtx_cost (XEXP (x, i), code); 3293169689Skan else if (fmt[i] == 'E') 3294169689Skan for (j = 0; j < XVECLEN (x, i); j++) 3295169689Skan total += rtx_cost (XVECEXP (x, i, j), code); 3296169689Skan 3297169689Skan return total; 3298169689Skan} 3299169689Skan 3300169689Skan/* Return cost of address expression X. 3301169689Skan Expect that X is properly formed address reference. */ 3302169689Skan 3303169689Skanint 3304169689Skanaddress_cost (rtx x, enum machine_mode mode) 3305169689Skan{ 3306169689Skan /* We may be asked for cost of various unusual addresses, such as operands 3307169689Skan of push instruction. It is not worthwhile to complicate writing 3308169689Skan of the target hook by such cases. */ 3309169689Skan 3310169689Skan if (!memory_address_p (mode, x)) 3311169689Skan return 1000; 3312169689Skan 3313169689Skan return targetm.address_cost (x); 3314169689Skan} 3315169689Skan 3316169689Skan/* If the target doesn't override, compute the cost as with arithmetic. */ 3317169689Skan 3318169689Skanint 3319169689Skandefault_address_cost (rtx x) 3320169689Skan{ 3321169689Skan return rtx_cost (x, MEM); 3322169689Skan} 3323169689Skan 3324169689Skan 3325169689Skanunsigned HOST_WIDE_INT 3326169689Skannonzero_bits (rtx x, enum machine_mode mode) 3327169689Skan{ 3328169689Skan return cached_nonzero_bits (x, mode, NULL_RTX, VOIDmode, 0); 3329169689Skan} 3330169689Skan 3331169689Skanunsigned int 3332169689Skannum_sign_bit_copies (rtx x, enum machine_mode mode) 3333169689Skan{ 3334169689Skan return cached_num_sign_bit_copies (x, mode, NULL_RTX, VOIDmode, 0); 3335169689Skan} 3336169689Skan 3337169689Skan/* The function cached_nonzero_bits is a wrapper around nonzero_bits1. 3338169689Skan It avoids exponential behavior in nonzero_bits1 when X has 3339169689Skan identical subexpressions on the first or the second level. */ 3340169689Skan 3341169689Skanstatic unsigned HOST_WIDE_INT 3342169689Skancached_nonzero_bits (rtx x, enum machine_mode mode, rtx known_x, 3343169689Skan enum machine_mode known_mode, 3344169689Skan unsigned HOST_WIDE_INT known_ret) 3345169689Skan{ 3346169689Skan if (x == known_x && mode == known_mode) 3347169689Skan return known_ret; 3348169689Skan 3349169689Skan /* Try to find identical subexpressions. If found call 3350169689Skan nonzero_bits1 on X with the subexpressions as KNOWN_X and the 3351169689Skan precomputed value for the subexpression as KNOWN_RET. */ 3352169689Skan 3353169689Skan if (ARITHMETIC_P (x)) 3354117395Skan { 3355169689Skan rtx x0 = XEXP (x, 0); 3356169689Skan rtx x1 = XEXP (x, 1); 3357117395Skan 3358169689Skan /* Check the first level. */ 3359169689Skan if (x0 == x1) 3360169689Skan return nonzero_bits1 (x, mode, x0, mode, 3361169689Skan cached_nonzero_bits (x0, mode, known_x, 3362169689Skan known_mode, known_ret)); 3363169689Skan 3364169689Skan /* Check the second level. */ 3365169689Skan if (ARITHMETIC_P (x0) 3366169689Skan && (x1 == XEXP (x0, 0) || x1 == XEXP (x0, 1))) 3367169689Skan return nonzero_bits1 (x, mode, x1, mode, 3368169689Skan cached_nonzero_bits (x1, mode, known_x, 3369169689Skan known_mode, known_ret)); 3370169689Skan 3371169689Skan if (ARITHMETIC_P (x1) 3372169689Skan && (x0 == XEXP (x1, 0) || x0 == XEXP (x1, 1))) 3373169689Skan return nonzero_bits1 (x, mode, x0, mode, 3374169689Skan cached_nonzero_bits (x0, mode, known_x, 3375169689Skan known_mode, known_ret)); 3376117395Skan } 3377169689Skan 3378169689Skan return nonzero_bits1 (x, mode, known_x, known_mode, known_ret); 3379117395Skan} 3380117395Skan 3381169689Skan/* We let num_sign_bit_copies recur into nonzero_bits as that is useful. 3382169689Skan We don't let nonzero_bits recur into num_sign_bit_copies, because that 3383169689Skan is less useful. We can't allow both, because that results in exponential 3384169689Skan run time recursion. There is a nullstone testcase that triggered 3385169689Skan this. This macro avoids accidental uses of num_sign_bit_copies. */ 3386169689Skan#define cached_num_sign_bit_copies sorry_i_am_preventing_exponential_behavior 3387117395Skan 3388169689Skan/* Given an expression, X, compute which bits in X can be nonzero. 3389169689Skan We don't care about bits outside of those defined in MODE. 3390117395Skan 3391169689Skan For most X this is simply GET_MODE_MASK (GET_MODE (MODE)), but if X is 3392169689Skan an arithmetic operation, we can do better. */ 3393169689Skan 3394169689Skanstatic unsigned HOST_WIDE_INT 3395169689Skannonzero_bits1 (rtx x, enum machine_mode mode, rtx known_x, 3396169689Skan enum machine_mode known_mode, 3397169689Skan unsigned HOST_WIDE_INT known_ret) 3398117395Skan{ 3399169689Skan unsigned HOST_WIDE_INT nonzero = GET_MODE_MASK (mode); 3400169689Skan unsigned HOST_WIDE_INT inner_nz; 3401169689Skan enum rtx_code code; 3402169689Skan unsigned int mode_width = GET_MODE_BITSIZE (mode); 3403117395Skan 3404169689Skan /* For floating-point values, assume all bits are needed. */ 3405169689Skan if (FLOAT_MODE_P (GET_MODE (x)) || FLOAT_MODE_P (mode)) 3406169689Skan return nonzero; 3407169689Skan 3408169689Skan /* If X is wider than MODE, use its mode instead. */ 3409169689Skan if (GET_MODE_BITSIZE (GET_MODE (x)) > mode_width) 3410117395Skan { 3411169689Skan mode = GET_MODE (x); 3412169689Skan nonzero = GET_MODE_MASK (mode); 3413169689Skan mode_width = GET_MODE_BITSIZE (mode); 3414169689Skan } 3415169689Skan 3416169689Skan if (mode_width > HOST_BITS_PER_WIDE_INT) 3417169689Skan /* Our only callers in this case look for single bit values. So 3418169689Skan just return the mode mask. Those tests will then be false. */ 3419169689Skan return nonzero; 3420169689Skan 3421169689Skan#ifndef WORD_REGISTER_OPERATIONS 3422169689Skan /* If MODE is wider than X, but both are a single word for both the host 3423169689Skan and target machines, we can compute this from which bits of the 3424169689Skan object might be nonzero in its own mode, taking into account the fact 3425169689Skan that on many CISC machines, accessing an object in a wider mode 3426169689Skan causes the high-order bits to become undefined. So they are 3427169689Skan not known to be zero. */ 3428169689Skan 3429169689Skan if (GET_MODE (x) != VOIDmode && GET_MODE (x) != mode 3430169689Skan && GET_MODE_BITSIZE (GET_MODE (x)) <= BITS_PER_WORD 3431169689Skan && GET_MODE_BITSIZE (GET_MODE (x)) <= HOST_BITS_PER_WIDE_INT 3432169689Skan && GET_MODE_BITSIZE (mode) > GET_MODE_BITSIZE (GET_MODE (x))) 3433169689Skan { 3434169689Skan nonzero &= cached_nonzero_bits (x, GET_MODE (x), 3435169689Skan known_x, known_mode, known_ret); 3436169689Skan nonzero |= GET_MODE_MASK (mode) & ~GET_MODE_MASK (GET_MODE (x)); 3437169689Skan return nonzero; 3438169689Skan } 3439169689Skan#endif 3440169689Skan 3441169689Skan code = GET_CODE (x); 3442169689Skan switch (code) 3443169689Skan { 3444169689Skan case REG: 3445169689Skan#if defined(POINTERS_EXTEND_UNSIGNED) && !defined(HAVE_ptr_extend) 3446169689Skan /* If pointers extend unsigned and this is a pointer in Pmode, say that 3447169689Skan all the bits above ptr_mode are known to be zero. */ 3448169689Skan if (POINTERS_EXTEND_UNSIGNED && GET_MODE (x) == Pmode 3449169689Skan && REG_POINTER (x)) 3450169689Skan nonzero &= GET_MODE_MASK (ptr_mode); 3451169689Skan#endif 3452169689Skan 3453169689Skan /* Include declared information about alignment of pointers. */ 3454169689Skan /* ??? We don't properly preserve REG_POINTER changes across 3455169689Skan pointer-to-integer casts, so we can't trust it except for 3456169689Skan things that we know must be pointers. See execute/960116-1.c. */ 3457169689Skan if ((x == stack_pointer_rtx 3458169689Skan || x == frame_pointer_rtx 3459169689Skan || x == arg_pointer_rtx) 3460169689Skan && REGNO_POINTER_ALIGN (REGNO (x))) 3461169689Skan { 3462169689Skan unsigned HOST_WIDE_INT alignment 3463169689Skan = REGNO_POINTER_ALIGN (REGNO (x)) / BITS_PER_UNIT; 3464169689Skan 3465169689Skan#ifdef PUSH_ROUNDING 3466169689Skan /* If PUSH_ROUNDING is defined, it is possible for the 3467169689Skan stack to be momentarily aligned only to that amount, 3468169689Skan so we pick the least alignment. */ 3469169689Skan if (x == stack_pointer_rtx && PUSH_ARGS) 3470169689Skan alignment = MIN ((unsigned HOST_WIDE_INT) PUSH_ROUNDING (1), 3471169689Skan alignment); 3472169689Skan#endif 3473169689Skan 3474169689Skan nonzero &= ~(alignment - 1); 3475169689Skan } 3476169689Skan 3477169689Skan { 3478169689Skan unsigned HOST_WIDE_INT nonzero_for_hook = nonzero; 3479169689Skan rtx new = rtl_hooks.reg_nonzero_bits (x, mode, known_x, 3480169689Skan known_mode, known_ret, 3481169689Skan &nonzero_for_hook); 3482169689Skan 3483169689Skan if (new) 3484169689Skan nonzero_for_hook &= cached_nonzero_bits (new, mode, known_x, 3485169689Skan known_mode, known_ret); 3486169689Skan 3487169689Skan return nonzero_for_hook; 3488169689Skan } 3489169689Skan 3490169689Skan case CONST_INT: 3491169689Skan#ifdef SHORT_IMMEDIATES_SIGN_EXTEND 3492169689Skan /* If X is negative in MODE, sign-extend the value. */ 3493169689Skan if (INTVAL (x) > 0 && mode_width < BITS_PER_WORD 3494169689Skan && 0 != (INTVAL (x) & ((HOST_WIDE_INT) 1 << (mode_width - 1)))) 3495169689Skan return (INTVAL (x) | ((HOST_WIDE_INT) (-1) << mode_width)); 3496169689Skan#endif 3497169689Skan 3498169689Skan return INTVAL (x); 3499169689Skan 3500169689Skan case MEM: 3501169689Skan#ifdef LOAD_EXTEND_OP 3502169689Skan /* In many, if not most, RISC machines, reading a byte from memory 3503169689Skan zeros the rest of the register. Noticing that fact saves a lot 3504169689Skan of extra zero-extends. */ 3505169689Skan if (LOAD_EXTEND_OP (GET_MODE (x)) == ZERO_EXTEND) 3506169689Skan nonzero &= GET_MODE_MASK (GET_MODE (x)); 3507169689Skan#endif 3508117395Skan break; 3509169689Skan 3510169689Skan case EQ: case NE: 3511169689Skan case UNEQ: case LTGT: 3512169689Skan case GT: case GTU: case UNGT: 3513169689Skan case LT: case LTU: case UNLT: 3514169689Skan case GE: case GEU: case UNGE: 3515169689Skan case LE: case LEU: case UNLE: 3516169689Skan case UNORDERED: case ORDERED: 3517169689Skan /* If this produces an integer result, we know which bits are set. 3518169689Skan Code here used to clear bits outside the mode of X, but that is 3519169689Skan now done above. */ 3520169689Skan /* Mind that MODE is the mode the caller wants to look at this 3521169689Skan operation in, and not the actual operation mode. We can wind 3522169689Skan up with (subreg:DI (gt:V4HI x y)), and we don't have anything 3523169689Skan that describes the results of a vector compare. */ 3524169689Skan if (GET_MODE_CLASS (GET_MODE (x)) == MODE_INT 3525169689Skan && mode_width <= HOST_BITS_PER_WIDE_INT) 3526169689Skan nonzero = STORE_FLAG_VALUE; 3527117395Skan break; 3528169689Skan 3529169689Skan case NEG: 3530169689Skan#if 0 3531169689Skan /* Disabled to avoid exponential mutual recursion between nonzero_bits 3532169689Skan and num_sign_bit_copies. */ 3533169689Skan if (num_sign_bit_copies (XEXP (x, 0), GET_MODE (x)) 3534169689Skan == GET_MODE_BITSIZE (GET_MODE (x))) 3535169689Skan nonzero = 1; 3536169689Skan#endif 3537169689Skan 3538169689Skan if (GET_MODE_SIZE (GET_MODE (x)) < mode_width) 3539169689Skan nonzero |= (GET_MODE_MASK (mode) & ~GET_MODE_MASK (GET_MODE (x))); 3540117395Skan break; 3541169689Skan 3542169689Skan case ABS: 3543169689Skan#if 0 3544169689Skan /* Disabled to avoid exponential mutual recursion between nonzero_bits 3545169689Skan and num_sign_bit_copies. */ 3546169689Skan if (num_sign_bit_copies (XEXP (x, 0), GET_MODE (x)) 3547169689Skan == GET_MODE_BITSIZE (GET_MODE (x))) 3548169689Skan nonzero = 1; 3549169689Skan#endif 3550169689Skan break; 3551169689Skan 3552169689Skan case TRUNCATE: 3553169689Skan nonzero &= (cached_nonzero_bits (XEXP (x, 0), mode, 3554169689Skan known_x, known_mode, known_ret) 3555169689Skan & GET_MODE_MASK (mode)); 3556169689Skan break; 3557169689Skan 3558169689Skan case ZERO_EXTEND: 3559169689Skan nonzero &= cached_nonzero_bits (XEXP (x, 0), mode, 3560169689Skan known_x, known_mode, known_ret); 3561169689Skan if (GET_MODE (XEXP (x, 0)) != VOIDmode) 3562169689Skan nonzero &= GET_MODE_MASK (GET_MODE (XEXP (x, 0))); 3563169689Skan break; 3564169689Skan 3565169689Skan case SIGN_EXTEND: 3566169689Skan /* If the sign bit is known clear, this is the same as ZERO_EXTEND. 3567169689Skan Otherwise, show all the bits in the outer mode but not the inner 3568169689Skan may be nonzero. */ 3569169689Skan inner_nz = cached_nonzero_bits (XEXP (x, 0), mode, 3570169689Skan known_x, known_mode, known_ret); 3571169689Skan if (GET_MODE (XEXP (x, 0)) != VOIDmode) 3572117395Skan { 3573169689Skan inner_nz &= GET_MODE_MASK (GET_MODE (XEXP (x, 0))); 3574169689Skan if (inner_nz 3575169689Skan & (((HOST_WIDE_INT) 1 3576169689Skan << (GET_MODE_BITSIZE (GET_MODE (XEXP (x, 0))) - 1)))) 3577169689Skan inner_nz |= (GET_MODE_MASK (mode) 3578169689Skan & ~GET_MODE_MASK (GET_MODE (XEXP (x, 0)))); 3579169689Skan } 3580169689Skan 3581169689Skan nonzero &= inner_nz; 3582169689Skan break; 3583169689Skan 3584169689Skan case AND: 3585169689Skan nonzero &= cached_nonzero_bits (XEXP (x, 0), mode, 3586169689Skan known_x, known_mode, known_ret) 3587169689Skan & cached_nonzero_bits (XEXP (x, 1), mode, 3588169689Skan known_x, known_mode, known_ret); 3589169689Skan break; 3590169689Skan 3591169689Skan case XOR: case IOR: 3592169689Skan case UMIN: case UMAX: case SMIN: case SMAX: 3593169689Skan { 3594169689Skan unsigned HOST_WIDE_INT nonzero0 = 3595169689Skan cached_nonzero_bits (XEXP (x, 0), mode, 3596169689Skan known_x, known_mode, known_ret); 3597169689Skan 3598169689Skan /* Don't call nonzero_bits for the second time if it cannot change 3599169689Skan anything. */ 3600169689Skan if ((nonzero & nonzero0) != nonzero) 3601169689Skan nonzero &= nonzero0 3602169689Skan | cached_nonzero_bits (XEXP (x, 1), mode, 3603169689Skan known_x, known_mode, known_ret); 3604169689Skan } 3605169689Skan break; 3606169689Skan 3607169689Skan case PLUS: case MINUS: 3608169689Skan case MULT: 3609169689Skan case DIV: case UDIV: 3610169689Skan case MOD: case UMOD: 3611169689Skan /* We can apply the rules of arithmetic to compute the number of 3612169689Skan high- and low-order zero bits of these operations. We start by 3613169689Skan computing the width (position of the highest-order nonzero bit) 3614169689Skan and the number of low-order zero bits for each value. */ 3615169689Skan { 3616169689Skan unsigned HOST_WIDE_INT nz0 = 3617169689Skan cached_nonzero_bits (XEXP (x, 0), mode, 3618169689Skan known_x, known_mode, known_ret); 3619169689Skan unsigned HOST_WIDE_INT nz1 = 3620169689Skan cached_nonzero_bits (XEXP (x, 1), mode, 3621169689Skan known_x, known_mode, known_ret); 3622169689Skan int sign_index = GET_MODE_BITSIZE (GET_MODE (x)) - 1; 3623169689Skan int width0 = floor_log2 (nz0) + 1; 3624169689Skan int width1 = floor_log2 (nz1) + 1; 3625169689Skan int low0 = floor_log2 (nz0 & -nz0); 3626169689Skan int low1 = floor_log2 (nz1 & -nz1); 3627169689Skan HOST_WIDE_INT op0_maybe_minusp 3628169689Skan = (nz0 & ((HOST_WIDE_INT) 1 << sign_index)); 3629169689Skan HOST_WIDE_INT op1_maybe_minusp 3630169689Skan = (nz1 & ((HOST_WIDE_INT) 1 << sign_index)); 3631169689Skan unsigned int result_width = mode_width; 3632169689Skan int result_low = 0; 3633169689Skan 3634169689Skan switch (code) 3635169689Skan { 3636169689Skan case PLUS: 3637169689Skan result_width = MAX (width0, width1) + 1; 3638169689Skan result_low = MIN (low0, low1); 3639169689Skan break; 3640169689Skan case MINUS: 3641169689Skan result_low = MIN (low0, low1); 3642169689Skan break; 3643169689Skan case MULT: 3644169689Skan result_width = width0 + width1; 3645169689Skan result_low = low0 + low1; 3646169689Skan break; 3647169689Skan case DIV: 3648169689Skan if (width1 == 0) 3649117395Skan break; 3650169689Skan if (! op0_maybe_minusp && ! op1_maybe_minusp) 3651169689Skan result_width = width0; 3652169689Skan break; 3653169689Skan case UDIV: 3654169689Skan if (width1 == 0) 3655117395Skan break; 3656169689Skan result_width = width0; 3657169689Skan break; 3658169689Skan case MOD: 3659169689Skan if (width1 == 0) 3660117395Skan break; 3661169689Skan if (! op0_maybe_minusp && ! op1_maybe_minusp) 3662169689Skan result_width = MIN (width0, width1); 3663169689Skan result_low = MIN (low0, low1); 3664169689Skan break; 3665169689Skan case UMOD: 3666169689Skan if (width1 == 0) 3667117395Skan break; 3668169689Skan result_width = MIN (width0, width1); 3669169689Skan result_low = MIN (low0, low1); 3670169689Skan break; 3671169689Skan default: 3672169689Skan gcc_unreachable (); 3673169689Skan } 3674169689Skan 3675169689Skan if (result_width < mode_width) 3676169689Skan nonzero &= ((HOST_WIDE_INT) 1 << result_width) - 1; 3677169689Skan 3678169689Skan if (result_low > 0) 3679169689Skan nonzero &= ~(((HOST_WIDE_INT) 1 << result_low) - 1); 3680169689Skan 3681169689Skan#ifdef POINTERS_EXTEND_UNSIGNED 3682169689Skan /* If pointers extend unsigned and this is an addition or subtraction 3683169689Skan to a pointer in Pmode, all the bits above ptr_mode are known to be 3684169689Skan zero. */ 3685169689Skan if (POINTERS_EXTEND_UNSIGNED > 0 && GET_MODE (x) == Pmode 3686169689Skan && (code == PLUS || code == MINUS) 3687169689Skan && REG_P (XEXP (x, 0)) && REG_POINTER (XEXP (x, 0))) 3688169689Skan nonzero &= GET_MODE_MASK (ptr_mode); 3689169689Skan#endif 3690169689Skan } 3691169689Skan break; 3692169689Skan 3693169689Skan case ZERO_EXTRACT: 3694169689Skan if (GET_CODE (XEXP (x, 1)) == CONST_INT 3695169689Skan && INTVAL (XEXP (x, 1)) < HOST_BITS_PER_WIDE_INT) 3696169689Skan nonzero &= ((HOST_WIDE_INT) 1 << INTVAL (XEXP (x, 1))) - 1; 3697169689Skan break; 3698169689Skan 3699169689Skan case SUBREG: 3700169689Skan /* If this is a SUBREG formed for a promoted variable that has 3701169689Skan been zero-extended, we know that at least the high-order bits 3702169689Skan are zero, though others might be too. */ 3703169689Skan 3704169689Skan if (SUBREG_PROMOTED_VAR_P (x) && SUBREG_PROMOTED_UNSIGNED_P (x) > 0) 3705169689Skan nonzero = GET_MODE_MASK (GET_MODE (x)) 3706169689Skan & cached_nonzero_bits (SUBREG_REG (x), GET_MODE (x), 3707169689Skan known_x, known_mode, known_ret); 3708169689Skan 3709169689Skan /* If the inner mode is a single word for both the host and target 3710169689Skan machines, we can compute this from which bits of the inner 3711169689Skan object might be nonzero. */ 3712169689Skan if (GET_MODE_BITSIZE (GET_MODE (SUBREG_REG (x))) <= BITS_PER_WORD 3713169689Skan && (GET_MODE_BITSIZE (GET_MODE (SUBREG_REG (x))) 3714169689Skan <= HOST_BITS_PER_WIDE_INT)) 3715169689Skan { 3716169689Skan nonzero &= cached_nonzero_bits (SUBREG_REG (x), mode, 3717169689Skan known_x, known_mode, known_ret); 3718169689Skan 3719169689Skan#if defined (WORD_REGISTER_OPERATIONS) && defined (LOAD_EXTEND_OP) 3720169689Skan /* If this is a typical RISC machine, we only have to worry 3721169689Skan about the way loads are extended. */ 3722169689Skan if ((LOAD_EXTEND_OP (GET_MODE (SUBREG_REG (x))) == SIGN_EXTEND 3723169689Skan ? (((nonzero 3724169689Skan & (((unsigned HOST_WIDE_INT) 1 3725169689Skan << (GET_MODE_BITSIZE (GET_MODE (SUBREG_REG (x))) - 1)))) 3726169689Skan != 0)) 3727169689Skan : LOAD_EXTEND_OP (GET_MODE (SUBREG_REG (x))) != ZERO_EXTEND) 3728169689Skan || !MEM_P (SUBREG_REG (x))) 3729169689Skan#endif 3730169689Skan { 3731169689Skan /* On many CISC machines, accessing an object in a wider mode 3732169689Skan causes the high-order bits to become undefined. So they are 3733169689Skan not known to be zero. */ 3734169689Skan if (GET_MODE_SIZE (GET_MODE (x)) 3735169689Skan > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)))) 3736169689Skan nonzero |= (GET_MODE_MASK (GET_MODE (x)) 3737169689Skan & ~GET_MODE_MASK (GET_MODE (SUBREG_REG (x)))); 3738117395Skan } 3739117395Skan } 3740117395Skan break; 3741169689Skan 3742169689Skan case ASHIFTRT: 3743169689Skan case LSHIFTRT: 3744169689Skan case ASHIFT: 3745169689Skan case ROTATE: 3746169689Skan /* The nonzero bits are in two classes: any bits within MODE 3747169689Skan that aren't in GET_MODE (x) are always significant. The rest of the 3748169689Skan nonzero bits are those that are significant in the operand of 3749169689Skan the shift when shifted the appropriate number of bits. This 3750169689Skan shows that high-order bits are cleared by the right shift and 3751169689Skan low-order bits by left shifts. */ 3752169689Skan if (GET_CODE (XEXP (x, 1)) == CONST_INT 3753169689Skan && INTVAL (XEXP (x, 1)) >= 0 3754169689Skan && INTVAL (XEXP (x, 1)) < HOST_BITS_PER_WIDE_INT) 3755169689Skan { 3756169689Skan enum machine_mode inner_mode = GET_MODE (x); 3757169689Skan unsigned int width = GET_MODE_BITSIZE (inner_mode); 3758169689Skan int count = INTVAL (XEXP (x, 1)); 3759169689Skan unsigned HOST_WIDE_INT mode_mask = GET_MODE_MASK (inner_mode); 3760169689Skan unsigned HOST_WIDE_INT op_nonzero = 3761169689Skan cached_nonzero_bits (XEXP (x, 0), mode, 3762169689Skan known_x, known_mode, known_ret); 3763169689Skan unsigned HOST_WIDE_INT inner = op_nonzero & mode_mask; 3764169689Skan unsigned HOST_WIDE_INT outer = 0; 3765169689Skan 3766169689Skan if (mode_width > width) 3767169689Skan outer = (op_nonzero & nonzero & ~mode_mask); 3768169689Skan 3769169689Skan if (code == LSHIFTRT) 3770169689Skan inner >>= count; 3771169689Skan else if (code == ASHIFTRT) 3772169689Skan { 3773169689Skan inner >>= count; 3774169689Skan 3775169689Skan /* If the sign bit may have been nonzero before the shift, we 3776169689Skan need to mark all the places it could have been copied to 3777169689Skan by the shift as possibly nonzero. */ 3778169689Skan if (inner & ((HOST_WIDE_INT) 1 << (width - 1 - count))) 3779169689Skan inner |= (((HOST_WIDE_INT) 1 << count) - 1) << (width - count); 3780169689Skan } 3781169689Skan else if (code == ASHIFT) 3782169689Skan inner <<= count; 3783169689Skan else 3784169689Skan inner = ((inner << (count % width) 3785169689Skan | (inner >> (width - (count % width)))) & mode_mask); 3786169689Skan 3787169689Skan nonzero &= (outer | inner); 3788169689Skan } 3789169689Skan break; 3790169689Skan 3791169689Skan case FFS: 3792169689Skan case POPCOUNT: 3793169689Skan /* This is at most the number of bits in the mode. */ 3794169689Skan nonzero = ((HOST_WIDE_INT) 2 << (floor_log2 (mode_width))) - 1; 3795169689Skan break; 3796169689Skan 3797169689Skan case CLZ: 3798169689Skan /* If CLZ has a known value at zero, then the nonzero bits are 3799169689Skan that value, plus the number of bits in the mode minus one. */ 3800169689Skan if (CLZ_DEFINED_VALUE_AT_ZERO (mode, nonzero)) 3801169689Skan nonzero |= ((HOST_WIDE_INT) 1 << (floor_log2 (mode_width))) - 1; 3802169689Skan else 3803169689Skan nonzero = -1; 3804169689Skan break; 3805169689Skan 3806169689Skan case CTZ: 3807169689Skan /* If CTZ has a known value at zero, then the nonzero bits are 3808169689Skan that value, plus the number of bits in the mode minus one. */ 3809169689Skan if (CTZ_DEFINED_VALUE_AT_ZERO (mode, nonzero)) 3810169689Skan nonzero |= ((HOST_WIDE_INT) 1 << (floor_log2 (mode_width))) - 1; 3811169689Skan else 3812169689Skan nonzero = -1; 3813169689Skan break; 3814169689Skan 3815169689Skan case PARITY: 3816169689Skan nonzero = 1; 3817169689Skan break; 3818169689Skan 3819169689Skan case IF_THEN_ELSE: 3820169689Skan { 3821169689Skan unsigned HOST_WIDE_INT nonzero_true = 3822169689Skan cached_nonzero_bits (XEXP (x, 1), mode, 3823169689Skan known_x, known_mode, known_ret); 3824169689Skan 3825169689Skan /* Don't call nonzero_bits for the second time if it cannot change 3826169689Skan anything. */ 3827169689Skan if ((nonzero & nonzero_true) != nonzero) 3828169689Skan nonzero &= nonzero_true 3829169689Skan | cached_nonzero_bits (XEXP (x, 2), mode, 3830169689Skan known_x, known_mode, known_ret); 3831169689Skan } 3832169689Skan break; 3833169689Skan 3834117395Skan default: 3835169689Skan break; 3836117395Skan } 3837169689Skan 3838169689Skan return nonzero; 3839117395Skan} 3840117395Skan 3841169689Skan/* See the macro definition above. */ 3842169689Skan#undef cached_num_sign_bit_copies 3843117395Skan 3844169689Skan 3845169689Skan/* The function cached_num_sign_bit_copies is a wrapper around 3846169689Skan num_sign_bit_copies1. It avoids exponential behavior in 3847169689Skan num_sign_bit_copies1 when X has identical subexpressions on the 3848169689Skan first or the second level. */ 3849169689Skan 3850169689Skanstatic unsigned int 3851169689Skancached_num_sign_bit_copies (rtx x, enum machine_mode mode, rtx known_x, 3852169689Skan enum machine_mode known_mode, 3853169689Skan unsigned int known_ret) 3854117395Skan{ 3855169689Skan if (x == known_x && mode == known_mode) 3856169689Skan return known_ret; 3857117395Skan 3858169689Skan /* Try to find identical subexpressions. If found call 3859169689Skan num_sign_bit_copies1 on X with the subexpressions as KNOWN_X and 3860169689Skan the precomputed value for the subexpression as KNOWN_RET. */ 3861117395Skan 3862169689Skan if (ARITHMETIC_P (x)) 3863117395Skan { 3864169689Skan rtx x0 = XEXP (x, 0); 3865169689Skan rtx x1 = XEXP (x, 1); 3866169689Skan 3867169689Skan /* Check the first level. */ 3868169689Skan if (x0 == x1) 3869169689Skan return 3870169689Skan num_sign_bit_copies1 (x, mode, x0, mode, 3871169689Skan cached_num_sign_bit_copies (x0, mode, known_x, 3872169689Skan known_mode, 3873169689Skan known_ret)); 3874169689Skan 3875169689Skan /* Check the second level. */ 3876169689Skan if (ARITHMETIC_P (x0) 3877169689Skan && (x1 == XEXP (x0, 0) || x1 == XEXP (x0, 1))) 3878169689Skan return 3879169689Skan num_sign_bit_copies1 (x, mode, x1, mode, 3880169689Skan cached_num_sign_bit_copies (x1, mode, known_x, 3881169689Skan known_mode, 3882169689Skan known_ret)); 3883169689Skan 3884169689Skan if (ARITHMETIC_P (x1) 3885169689Skan && (x0 == XEXP (x1, 0) || x0 == XEXP (x1, 1))) 3886169689Skan return 3887169689Skan num_sign_bit_copies1 (x, mode, x0, mode, 3888169689Skan cached_num_sign_bit_copies (x0, mode, known_x, 3889169689Skan known_mode, 3890169689Skan known_ret)); 3891117395Skan } 3892117395Skan 3893169689Skan return num_sign_bit_copies1 (x, mode, known_x, known_mode, known_ret); 3894117395Skan} 3895117395Skan 3896169689Skan/* Return the number of bits at the high-order end of X that are known to 3897169689Skan be equal to the sign bit. X will be used in mode MODE; if MODE is 3898169689Skan VOIDmode, X will be used in its own mode. The returned value will always 3899169689Skan be between 1 and the number of bits in MODE. */ 3900117395Skan 3901169689Skanstatic unsigned int 3902169689Skannum_sign_bit_copies1 (rtx x, enum machine_mode mode, rtx known_x, 3903169689Skan enum machine_mode known_mode, 3904169689Skan unsigned int known_ret) 3905117395Skan{ 3906169689Skan enum rtx_code code = GET_CODE (x); 3907169689Skan unsigned int bitwidth = GET_MODE_BITSIZE (mode); 3908169689Skan int num0, num1, result; 3909169689Skan unsigned HOST_WIDE_INT nonzero; 3910117395Skan 3911169689Skan /* If we weren't given a mode, use the mode of X. If the mode is still 3912169689Skan VOIDmode, we don't know anything. Likewise if one of the modes is 3913169689Skan floating-point. */ 3914117395Skan 3915169689Skan if (mode == VOIDmode) 3916169689Skan mode = GET_MODE (x); 3917117395Skan 3918169689Skan if (mode == VOIDmode || FLOAT_MODE_P (mode) || FLOAT_MODE_P (GET_MODE (x))) 3919169689Skan return 1; 3920117395Skan 3921169689Skan /* For a smaller object, just ignore the high bits. */ 3922169689Skan if (bitwidth < GET_MODE_BITSIZE (GET_MODE (x))) 3923117395Skan { 3924169689Skan num0 = cached_num_sign_bit_copies (x, GET_MODE (x), 3925169689Skan known_x, known_mode, known_ret); 3926169689Skan return MAX (1, 3927169689Skan num0 - (int) (GET_MODE_BITSIZE (GET_MODE (x)) - bitwidth)); 3928169689Skan } 3929169689Skan 3930169689Skan if (GET_MODE (x) != VOIDmode && bitwidth > GET_MODE_BITSIZE (GET_MODE (x))) 3931169689Skan { 3932169689Skan#ifndef WORD_REGISTER_OPERATIONS 3933169689Skan /* If this machine does not do all register operations on the entire 3934169689Skan register and MODE is wider than the mode of X, we can say nothing 3935169689Skan at all about the high-order bits. */ 3936169689Skan return 1; 3937169689Skan#else 3938169689Skan /* Likewise on machines that do, if the mode of the object is smaller 3939169689Skan than a word and loads of that size don't sign extend, we can say 3940169689Skan nothing about the high order bits. */ 3941169689Skan if (GET_MODE_BITSIZE (GET_MODE (x)) < BITS_PER_WORD 3942169689Skan#ifdef LOAD_EXTEND_OP 3943169689Skan && LOAD_EXTEND_OP (GET_MODE (x)) != SIGN_EXTEND 3944169689Skan#endif 3945169689Skan ) 3946169689Skan return 1; 3947169689Skan#endif 3948169689Skan } 3949169689Skan 3950169689Skan switch (code) 3951169689Skan { 3952169689Skan case REG: 3953169689Skan 3954169689Skan#if defined(POINTERS_EXTEND_UNSIGNED) && !defined(HAVE_ptr_extend) 3955169689Skan /* If pointers extend signed and this is a pointer in Pmode, say that 3956169689Skan all the bits above ptr_mode are known to be sign bit copies. */ 3957169689Skan if (! POINTERS_EXTEND_UNSIGNED && GET_MODE (x) == Pmode && mode == Pmode 3958169689Skan && REG_POINTER (x)) 3959169689Skan return GET_MODE_BITSIZE (Pmode) - GET_MODE_BITSIZE (ptr_mode) + 1; 3960169689Skan#endif 3961169689Skan 3962169689Skan { 3963169689Skan unsigned int copies_for_hook = 1, copies = 1; 3964169689Skan rtx new = rtl_hooks.reg_num_sign_bit_copies (x, mode, known_x, 3965169689Skan known_mode, known_ret, 3966169689Skan &copies_for_hook); 3967169689Skan 3968169689Skan if (new) 3969169689Skan copies = cached_num_sign_bit_copies (new, mode, known_x, 3970169689Skan known_mode, known_ret); 3971169689Skan 3972169689Skan if (copies > 1 || copies_for_hook > 1) 3973169689Skan return MAX (copies, copies_for_hook); 3974169689Skan 3975169689Skan /* Else, use nonzero_bits to guess num_sign_bit_copies (see below). */ 3976169689Skan } 3977117395Skan break; 3978169689Skan 3979169689Skan case MEM: 3980169689Skan#ifdef LOAD_EXTEND_OP 3981169689Skan /* Some RISC machines sign-extend all loads of smaller than a word. */ 3982169689Skan if (LOAD_EXTEND_OP (GET_MODE (x)) == SIGN_EXTEND) 3983169689Skan return MAX (1, ((int) bitwidth 3984169689Skan - (int) GET_MODE_BITSIZE (GET_MODE (x)) + 1)); 3985169689Skan#endif 3986117395Skan break; 3987169689Skan 3988169689Skan case CONST_INT: 3989169689Skan /* If the constant is negative, take its 1's complement and remask. 3990169689Skan Then see how many zero bits we have. */ 3991169689Skan nonzero = INTVAL (x) & GET_MODE_MASK (mode); 3992169689Skan if (bitwidth <= HOST_BITS_PER_WIDE_INT 3993169689Skan && (nonzero & ((HOST_WIDE_INT) 1 << (bitwidth - 1))) != 0) 3994169689Skan nonzero = (~nonzero) & GET_MODE_MASK (mode); 3995169689Skan 3996169689Skan return (nonzero == 0 ? bitwidth : bitwidth - floor_log2 (nonzero) - 1); 3997169689Skan 3998169689Skan case SUBREG: 3999169689Skan /* If this is a SUBREG for a promoted object that is sign-extended 4000169689Skan and we are looking at it in a wider mode, we know that at least the 4001169689Skan high-order bits are known to be sign bit copies. */ 4002169689Skan 4003169689Skan if (SUBREG_PROMOTED_VAR_P (x) && ! SUBREG_PROMOTED_UNSIGNED_P (x)) 4004169689Skan { 4005169689Skan num0 = cached_num_sign_bit_copies (SUBREG_REG (x), mode, 4006169689Skan known_x, known_mode, known_ret); 4007169689Skan return MAX ((int) bitwidth 4008169689Skan - (int) GET_MODE_BITSIZE (GET_MODE (x)) + 1, 4009169689Skan num0); 4010169689Skan } 4011169689Skan 4012169689Skan /* For a smaller object, just ignore the high bits. */ 4013169689Skan if (bitwidth <= GET_MODE_BITSIZE (GET_MODE (SUBREG_REG (x)))) 4014169689Skan { 4015169689Skan num0 = cached_num_sign_bit_copies (SUBREG_REG (x), VOIDmode, 4016169689Skan known_x, known_mode, known_ret); 4017169689Skan return MAX (1, (num0 4018169689Skan - (int) (GET_MODE_BITSIZE (GET_MODE (SUBREG_REG (x))) 4019169689Skan - bitwidth))); 4020169689Skan } 4021169689Skan 4022169689Skan#ifdef WORD_REGISTER_OPERATIONS 4023169689Skan#ifdef LOAD_EXTEND_OP 4024169689Skan /* For paradoxical SUBREGs on machines where all register operations 4025169689Skan affect the entire register, just look inside. Note that we are 4026169689Skan passing MODE to the recursive call, so the number of sign bit copies 4027169689Skan will remain relative to that mode, not the inner mode. */ 4028169689Skan 4029169689Skan /* This works only if loads sign extend. Otherwise, if we get a 4030169689Skan reload for the inner part, it may be loaded from the stack, and 4031169689Skan then we lose all sign bit copies that existed before the store 4032169689Skan to the stack. */ 4033169689Skan 4034169689Skan if ((GET_MODE_SIZE (GET_MODE (x)) 4035169689Skan > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)))) 4036169689Skan && LOAD_EXTEND_OP (GET_MODE (SUBREG_REG (x))) == SIGN_EXTEND 4037169689Skan && MEM_P (SUBREG_REG (x))) 4038169689Skan return cached_num_sign_bit_copies (SUBREG_REG (x), mode, 4039169689Skan known_x, known_mode, known_ret); 4040169689Skan#endif 4041169689Skan#endif 4042117395Skan break; 4043169689Skan 4044169689Skan case SIGN_EXTRACT: 4045169689Skan if (GET_CODE (XEXP (x, 1)) == CONST_INT) 4046169689Skan return MAX (1, (int) bitwidth - INTVAL (XEXP (x, 1))); 4047169689Skan break; 4048169689Skan 4049169689Skan case SIGN_EXTEND: 4050169689Skan return (bitwidth - GET_MODE_BITSIZE (GET_MODE (XEXP (x, 0))) 4051169689Skan + cached_num_sign_bit_copies (XEXP (x, 0), VOIDmode, 4052169689Skan known_x, known_mode, known_ret)); 4053169689Skan 4054169689Skan case TRUNCATE: 4055169689Skan /* For a smaller object, just ignore the high bits. */ 4056169689Skan num0 = cached_num_sign_bit_copies (XEXP (x, 0), VOIDmode, 4057169689Skan known_x, known_mode, known_ret); 4058169689Skan return MAX (1, (num0 - (int) (GET_MODE_BITSIZE (GET_MODE (XEXP (x, 0))) 4059169689Skan - bitwidth))); 4060169689Skan 4061169689Skan case NOT: 4062169689Skan return cached_num_sign_bit_copies (XEXP (x, 0), mode, 4063169689Skan known_x, known_mode, known_ret); 4064169689Skan 4065169689Skan case ROTATE: case ROTATERT: 4066169689Skan /* If we are rotating left by a number of bits less than the number 4067169689Skan of sign bit copies, we can just subtract that amount from the 4068169689Skan number. */ 4069169689Skan if (GET_CODE (XEXP (x, 1)) == CONST_INT 4070169689Skan && INTVAL (XEXP (x, 1)) >= 0 4071169689Skan && INTVAL (XEXP (x, 1)) < (int) bitwidth) 4072169689Skan { 4073169689Skan num0 = cached_num_sign_bit_copies (XEXP (x, 0), mode, 4074169689Skan known_x, known_mode, known_ret); 4075169689Skan return MAX (1, num0 - (code == ROTATE ? INTVAL (XEXP (x, 1)) 4076169689Skan : (int) bitwidth - INTVAL (XEXP (x, 1)))); 4077169689Skan } 4078169689Skan break; 4079169689Skan 4080169689Skan case NEG: 4081169689Skan /* In general, this subtracts one sign bit copy. But if the value 4082169689Skan is known to be positive, the number of sign bit copies is the 4083169689Skan same as that of the input. Finally, if the input has just one bit 4084169689Skan that might be nonzero, all the bits are copies of the sign bit. */ 4085169689Skan num0 = cached_num_sign_bit_copies (XEXP (x, 0), mode, 4086169689Skan known_x, known_mode, known_ret); 4087169689Skan if (bitwidth > HOST_BITS_PER_WIDE_INT) 4088169689Skan return num0 > 1 ? num0 - 1 : 1; 4089169689Skan 4090169689Skan nonzero = nonzero_bits (XEXP (x, 0), mode); 4091169689Skan if (nonzero == 1) 4092169689Skan return bitwidth; 4093169689Skan 4094169689Skan if (num0 > 1 4095169689Skan && (((HOST_WIDE_INT) 1 << (bitwidth - 1)) & nonzero)) 4096169689Skan num0--; 4097169689Skan 4098169689Skan return num0; 4099169689Skan 4100169689Skan case IOR: case AND: case XOR: 4101169689Skan case SMIN: case SMAX: case UMIN: case UMAX: 4102169689Skan /* Logical operations will preserve the number of sign-bit copies. 4103169689Skan MIN and MAX operations always return one of the operands. */ 4104169689Skan num0 = cached_num_sign_bit_copies (XEXP (x, 0), mode, 4105169689Skan known_x, known_mode, known_ret); 4106169689Skan num1 = cached_num_sign_bit_copies (XEXP (x, 1), mode, 4107169689Skan known_x, known_mode, known_ret); 4108169689Skan return MIN (num0, num1); 4109169689Skan 4110169689Skan case PLUS: case MINUS: 4111169689Skan /* For addition and subtraction, we can have a 1-bit carry. However, 4112169689Skan if we are subtracting 1 from a positive number, there will not 4113169689Skan be such a carry. Furthermore, if the positive number is known to 4114169689Skan be 0 or 1, we know the result is either -1 or 0. */ 4115169689Skan 4116169689Skan if (code == PLUS && XEXP (x, 1) == constm1_rtx 4117169689Skan && bitwidth <= HOST_BITS_PER_WIDE_INT) 4118169689Skan { 4119169689Skan nonzero = nonzero_bits (XEXP (x, 0), mode); 4120169689Skan if ((((HOST_WIDE_INT) 1 << (bitwidth - 1)) & nonzero) == 0) 4121169689Skan return (nonzero == 1 || nonzero == 0 ? bitwidth 4122169689Skan : bitwidth - floor_log2 (nonzero) - 1); 4123169689Skan } 4124169689Skan 4125169689Skan num0 = cached_num_sign_bit_copies (XEXP (x, 0), mode, 4126169689Skan known_x, known_mode, known_ret); 4127169689Skan num1 = cached_num_sign_bit_copies (XEXP (x, 1), mode, 4128169689Skan known_x, known_mode, known_ret); 4129169689Skan result = MAX (1, MIN (num0, num1) - 1); 4130169689Skan 4131169689Skan#ifdef POINTERS_EXTEND_UNSIGNED 4132169689Skan /* If pointers extend signed and this is an addition or subtraction 4133169689Skan to a pointer in Pmode, all the bits above ptr_mode are known to be 4134169689Skan sign bit copies. */ 4135169689Skan if (! POINTERS_EXTEND_UNSIGNED && GET_MODE (x) == Pmode 4136169689Skan && (code == PLUS || code == MINUS) 4137169689Skan && REG_P (XEXP (x, 0)) && REG_POINTER (XEXP (x, 0))) 4138169689Skan result = MAX ((int) (GET_MODE_BITSIZE (Pmode) 4139169689Skan - GET_MODE_BITSIZE (ptr_mode) + 1), 4140169689Skan result); 4141169689Skan#endif 4142169689Skan return result; 4143169689Skan 4144169689Skan case MULT: 4145169689Skan /* The number of bits of the product is the sum of the number of 4146169689Skan bits of both terms. However, unless one of the terms if known 4147169689Skan to be positive, we must allow for an additional bit since negating 4148169689Skan a negative number can remove one sign bit copy. */ 4149169689Skan 4150169689Skan num0 = cached_num_sign_bit_copies (XEXP (x, 0), mode, 4151169689Skan known_x, known_mode, known_ret); 4152169689Skan num1 = cached_num_sign_bit_copies (XEXP (x, 1), mode, 4153169689Skan known_x, known_mode, known_ret); 4154169689Skan 4155169689Skan result = bitwidth - (bitwidth - num0) - (bitwidth - num1); 4156169689Skan if (result > 0 4157169689Skan && (bitwidth > HOST_BITS_PER_WIDE_INT 4158169689Skan || (((nonzero_bits (XEXP (x, 0), mode) 4159169689Skan & ((HOST_WIDE_INT) 1 << (bitwidth - 1))) != 0) 4160169689Skan && ((nonzero_bits (XEXP (x, 1), mode) 4161169689Skan & ((HOST_WIDE_INT) 1 << (bitwidth - 1))) != 0)))) 4162169689Skan result--; 4163169689Skan 4164169689Skan return MAX (1, result); 4165169689Skan 4166169689Skan case UDIV: 4167169689Skan /* The result must be <= the first operand. If the first operand 4168169689Skan has the high bit set, we know nothing about the number of sign 4169169689Skan bit copies. */ 4170169689Skan if (bitwidth > HOST_BITS_PER_WIDE_INT) 4171169689Skan return 1; 4172169689Skan else if ((nonzero_bits (XEXP (x, 0), mode) 4173169689Skan & ((HOST_WIDE_INT) 1 << (bitwidth - 1))) != 0) 4174169689Skan return 1; 4175169689Skan else 4176169689Skan return cached_num_sign_bit_copies (XEXP (x, 0), mode, 4177169689Skan known_x, known_mode, known_ret); 4178169689Skan 4179169689Skan case UMOD: 4180169689Skan /* The result must be <= the second operand. */ 4181169689Skan return cached_num_sign_bit_copies (XEXP (x, 1), mode, 4182169689Skan known_x, known_mode, known_ret); 4183169689Skan 4184169689Skan case DIV: 4185169689Skan /* Similar to unsigned division, except that we have to worry about 4186169689Skan the case where the divisor is negative, in which case we have 4187169689Skan to add 1. */ 4188169689Skan result = cached_num_sign_bit_copies (XEXP (x, 0), mode, 4189169689Skan known_x, known_mode, known_ret); 4190169689Skan if (result > 1 4191169689Skan && (bitwidth > HOST_BITS_PER_WIDE_INT 4192169689Skan || (nonzero_bits (XEXP (x, 1), mode) 4193169689Skan & ((HOST_WIDE_INT) 1 << (bitwidth - 1))) != 0)) 4194169689Skan result--; 4195169689Skan 4196169689Skan return result; 4197169689Skan 4198169689Skan case MOD: 4199169689Skan result = cached_num_sign_bit_copies (XEXP (x, 1), mode, 4200169689Skan known_x, known_mode, known_ret); 4201169689Skan if (result > 1 4202169689Skan && (bitwidth > HOST_BITS_PER_WIDE_INT 4203169689Skan || (nonzero_bits (XEXP (x, 1), mode) 4204169689Skan & ((HOST_WIDE_INT) 1 << (bitwidth - 1))) != 0)) 4205169689Skan result--; 4206169689Skan 4207169689Skan return result; 4208169689Skan 4209169689Skan case ASHIFTRT: 4210169689Skan /* Shifts by a constant add to the number of bits equal to the 4211169689Skan sign bit. */ 4212169689Skan num0 = cached_num_sign_bit_copies (XEXP (x, 0), mode, 4213169689Skan known_x, known_mode, known_ret); 4214169689Skan if (GET_CODE (XEXP (x, 1)) == CONST_INT 4215169689Skan && INTVAL (XEXP (x, 1)) > 0) 4216169689Skan num0 = MIN ((int) bitwidth, num0 + INTVAL (XEXP (x, 1))); 4217169689Skan 4218169689Skan return num0; 4219169689Skan 4220169689Skan case ASHIFT: 4221169689Skan /* Left shifts destroy copies. */ 4222169689Skan if (GET_CODE (XEXP (x, 1)) != CONST_INT 4223169689Skan || INTVAL (XEXP (x, 1)) < 0 4224169689Skan || INTVAL (XEXP (x, 1)) >= (int) bitwidth) 4225169689Skan return 1; 4226169689Skan 4227169689Skan num0 = cached_num_sign_bit_copies (XEXP (x, 0), mode, 4228169689Skan known_x, known_mode, known_ret); 4229169689Skan return MAX (1, num0 - INTVAL (XEXP (x, 1))); 4230169689Skan 4231169689Skan case IF_THEN_ELSE: 4232169689Skan num0 = cached_num_sign_bit_copies (XEXP (x, 1), mode, 4233169689Skan known_x, known_mode, known_ret); 4234169689Skan num1 = cached_num_sign_bit_copies (XEXP (x, 2), mode, 4235169689Skan known_x, known_mode, known_ret); 4236169689Skan return MIN (num0, num1); 4237169689Skan 4238169689Skan case EQ: case NE: case GE: case GT: case LE: case LT: 4239169689Skan case UNEQ: case LTGT: case UNGE: case UNGT: case UNLE: case UNLT: 4240169689Skan case GEU: case GTU: case LEU: case LTU: 4241169689Skan case UNORDERED: case ORDERED: 4242169689Skan /* If the constant is negative, take its 1's complement and remask. 4243169689Skan Then see how many zero bits we have. */ 4244169689Skan nonzero = STORE_FLAG_VALUE; 4245169689Skan if (bitwidth <= HOST_BITS_PER_WIDE_INT 4246169689Skan && (nonzero & ((HOST_WIDE_INT) 1 << (bitwidth - 1))) != 0) 4247169689Skan nonzero = (~nonzero) & GET_MODE_MASK (mode); 4248169689Skan 4249169689Skan return (nonzero == 0 ? bitwidth : bitwidth - floor_log2 (nonzero) - 1); 4250169689Skan 4251169689Skan default: 4252169689Skan break; 4253169689Skan } 4254169689Skan 4255169689Skan /* If we haven't been able to figure it out by one of the above rules, 4256169689Skan see if some of the high-order bits are known to be zero. If so, 4257169689Skan count those bits and return one less than that amount. If we can't 4258169689Skan safely compute the mask for this mode, always return BITWIDTH. */ 4259169689Skan 4260169689Skan bitwidth = GET_MODE_BITSIZE (mode); 4261169689Skan if (bitwidth > HOST_BITS_PER_WIDE_INT) 4262169689Skan return 1; 4263169689Skan 4264169689Skan nonzero = nonzero_bits (x, mode); 4265169689Skan return nonzero & ((HOST_WIDE_INT) 1 << (bitwidth - 1)) 4266169689Skan ? 1 : bitwidth - floor_log2 (nonzero) - 1; 4267169689Skan} 4268169689Skan 4269169689Skan/* Calculate the rtx_cost of a single instruction. A return value of 4270169689Skan zero indicates an instruction pattern without a known cost. */ 4271169689Skan 4272169689Skanint 4273169689Skaninsn_rtx_cost (rtx pat) 4274169689Skan{ 4275169689Skan int i, cost; 4276169689Skan rtx set; 4277169689Skan 4278169689Skan /* Extract the single set rtx from the instruction pattern. 4279169689Skan We can't use single_set since we only have the pattern. */ 4280169689Skan if (GET_CODE (pat) == SET) 4281169689Skan set = pat; 4282169689Skan else if (GET_CODE (pat) == PARALLEL) 4283169689Skan { 4284169689Skan set = NULL_RTX; 4285117395Skan for (i = 0; i < XVECLEN (pat, 0); i++) 4286117395Skan { 4287117395Skan rtx x = XVECEXP (pat, 0, i); 4288169689Skan if (GET_CODE (x) == SET) 4289117395Skan { 4290169689Skan if (set) 4291169689Skan return 0; 4292169689Skan set = x; 4293117395Skan } 4294117395Skan } 4295169689Skan if (!set) 4296169689Skan return 0; 4297117395Skan } 4298169689Skan else 4299169689Skan return 0; 4300117395Skan 4301169689Skan cost = rtx_cost (SET_SRC (set), SET); 4302169689Skan return cost > 0 ? cost : COSTS_N_INSNS (1); 4303117395Skan} 4304117395Skan 4305169689Skan/* Given an insn INSN and condition COND, return the condition in a 4306169689Skan canonical form to simplify testing by callers. Specifically: 4307169689Skan 4308169689Skan (1) The code will always be a comparison operation (EQ, NE, GT, etc.). 4309169689Skan (2) Both operands will be machine operands; (cc0) will have been replaced. 4310169689Skan (3) If an operand is a constant, it will be the second operand. 4311169689Skan (4) (LE x const) will be replaced with (LT x <const+1>) and similarly 4312169689Skan for GE, GEU, and LEU. 4313169689Skan 4314169689Skan If the condition cannot be understood, or is an inequality floating-point 4315169689Skan comparison which needs to be reversed, 0 will be returned. 4316169689Skan 4317169689Skan If REVERSE is nonzero, then reverse the condition prior to canonizing it. 4318169689Skan 4319169689Skan If EARLIEST is nonzero, it is a pointer to a place where the earliest 4320169689Skan insn used in locating the condition was found. If a replacement test 4321169689Skan of the condition is desired, it should be placed in front of that 4322169689Skan insn and we will be sure that the inputs are still valid. 4323169689Skan 4324169689Skan If WANT_REG is nonzero, we wish the condition to be relative to that 4325169689Skan register, if possible. Therefore, do not canonicalize the condition 4326169689Skan further. If ALLOW_CC_MODE is nonzero, allow the condition returned 4327169689Skan to be a compare to a CC mode register. 4328169689Skan 4329169689Skan If VALID_AT_INSN_P, the condition must be valid at both *EARLIEST 4330169689Skan and at INSN. */ 4331169689Skan 4332117395Skanrtx 4333169689Skancanonicalize_condition (rtx insn, rtx cond, int reverse, rtx *earliest, 4334169689Skan rtx want_reg, int allow_cc_mode, int valid_at_insn_p) 4335117395Skan{ 4336169689Skan enum rtx_code code; 4337169689Skan rtx prev = insn; 4338169689Skan rtx set; 4339169689Skan rtx tem; 4340169689Skan rtx op0, op1; 4341169689Skan int reverse_code = 0; 4342169689Skan enum machine_mode mode; 4343169689Skan basic_block bb = BLOCK_FOR_INSN (insn); 4344117395Skan 4345169689Skan code = GET_CODE (cond); 4346169689Skan mode = GET_MODE (cond); 4347169689Skan op0 = XEXP (cond, 0); 4348169689Skan op1 = XEXP (cond, 1); 4349117395Skan 4350169689Skan if (reverse) 4351169689Skan code = reversed_comparison_code (cond, insn); 4352169689Skan if (code == UNKNOWN) 4353169689Skan return 0; 4354169689Skan 4355169689Skan if (earliest) 4356169689Skan *earliest = insn; 4357169689Skan 4358169689Skan /* If we are comparing a register with zero, see if the register is set 4359169689Skan in the previous insn to a COMPARE or a comparison operation. Perform 4360169689Skan the same tests as a function of STORE_FLAG_VALUE as find_comparison_args 4361169689Skan in cse.c */ 4362169689Skan 4363169689Skan while ((GET_RTX_CLASS (code) == RTX_COMPARE 4364169689Skan || GET_RTX_CLASS (code) == RTX_COMM_COMPARE) 4365169689Skan && op1 == CONST0_RTX (GET_MODE (op0)) 4366169689Skan && op0 != want_reg) 4367117395Skan { 4368169689Skan /* Set nonzero when we find something of interest. */ 4369169689Skan rtx x = 0; 4370169689Skan 4371169689Skan#ifdef HAVE_cc0 4372169689Skan /* If comparison with cc0, import actual comparison from compare 4373169689Skan insn. */ 4374169689Skan if (op0 == cc0_rtx) 4375169689Skan { 4376169689Skan if ((prev = prev_nonnote_insn (prev)) == 0 4377169689Skan || !NONJUMP_INSN_P (prev) 4378169689Skan || (set = single_set (prev)) == 0 4379169689Skan || SET_DEST (set) != cc0_rtx) 4380169689Skan return 0; 4381169689Skan 4382169689Skan op0 = SET_SRC (set); 4383169689Skan op1 = CONST0_RTX (GET_MODE (op0)); 4384169689Skan if (earliest) 4385169689Skan *earliest = prev; 4386169689Skan } 4387169689Skan#endif 4388169689Skan 4389169689Skan /* If this is a COMPARE, pick up the two things being compared. */ 4390169689Skan if (GET_CODE (op0) == COMPARE) 4391169689Skan { 4392169689Skan op1 = XEXP (op0, 1); 4393169689Skan op0 = XEXP (op0, 0); 4394169689Skan continue; 4395169689Skan } 4396169689Skan else if (!REG_P (op0)) 4397169689Skan break; 4398169689Skan 4399169689Skan /* Go back to the previous insn. Stop if it is not an INSN. We also 4400169689Skan stop if it isn't a single set or if it has a REG_INC note because 4401169689Skan we don't want to bother dealing with it. */ 4402169689Skan 4403169689Skan if ((prev = prev_nonnote_insn (prev)) == 0 4404169689Skan || !NONJUMP_INSN_P (prev) 4405169689Skan || FIND_REG_INC_NOTE (prev, NULL_RTX) 4406169689Skan /* In cfglayout mode, there do not have to be labels at the 4407169689Skan beginning of a block, or jumps at the end, so the previous 4408169689Skan conditions would not stop us when we reach bb boundary. */ 4409169689Skan || BLOCK_FOR_INSN (prev) != bb) 4410169689Skan break; 4411169689Skan 4412169689Skan set = set_of (op0, prev); 4413169689Skan 4414169689Skan if (set 4415169689Skan && (GET_CODE (set) != SET 4416169689Skan || !rtx_equal_p (SET_DEST (set), op0))) 4417169689Skan break; 4418169689Skan 4419169689Skan /* If this is setting OP0, get what it sets it to if it looks 4420169689Skan relevant. */ 4421169689Skan if (set) 4422169689Skan { 4423169689Skan enum machine_mode inner_mode = GET_MODE (SET_DEST (set)); 4424169689Skan#ifdef FLOAT_STORE_FLAG_VALUE 4425169689Skan REAL_VALUE_TYPE fsfv; 4426169689Skan#endif 4427169689Skan 4428169689Skan /* ??? We may not combine comparisons done in a CCmode with 4429169689Skan comparisons not done in a CCmode. This is to aid targets 4430169689Skan like Alpha that have an IEEE compliant EQ instruction, and 4431169689Skan a non-IEEE compliant BEQ instruction. The use of CCmode is 4432169689Skan actually artificial, simply to prevent the combination, but 4433169689Skan should not affect other platforms. 4434169689Skan 4435169689Skan However, we must allow VOIDmode comparisons to match either 4436169689Skan CCmode or non-CCmode comparison, because some ports have 4437169689Skan modeless comparisons inside branch patterns. 4438169689Skan 4439169689Skan ??? This mode check should perhaps look more like the mode check 4440169689Skan in simplify_comparison in combine. */ 4441169689Skan 4442169689Skan if ((GET_CODE (SET_SRC (set)) == COMPARE 4443169689Skan || (((code == NE 4444169689Skan || (code == LT 4445169689Skan && GET_MODE_CLASS (inner_mode) == MODE_INT 4446169689Skan && (GET_MODE_BITSIZE (inner_mode) 4447169689Skan <= HOST_BITS_PER_WIDE_INT) 4448169689Skan && (STORE_FLAG_VALUE 4449169689Skan & ((HOST_WIDE_INT) 1 4450169689Skan << (GET_MODE_BITSIZE (inner_mode) - 1)))) 4451169689Skan#ifdef FLOAT_STORE_FLAG_VALUE 4452169689Skan || (code == LT 4453169689Skan && SCALAR_FLOAT_MODE_P (inner_mode) 4454169689Skan && (fsfv = FLOAT_STORE_FLAG_VALUE (inner_mode), 4455169689Skan REAL_VALUE_NEGATIVE (fsfv))) 4456169689Skan#endif 4457169689Skan )) 4458169689Skan && COMPARISON_P (SET_SRC (set)))) 4459169689Skan && (((GET_MODE_CLASS (mode) == MODE_CC) 4460169689Skan == (GET_MODE_CLASS (inner_mode) == MODE_CC)) 4461169689Skan || mode == VOIDmode || inner_mode == VOIDmode)) 4462169689Skan x = SET_SRC (set); 4463169689Skan else if (((code == EQ 4464169689Skan || (code == GE 4465169689Skan && (GET_MODE_BITSIZE (inner_mode) 4466169689Skan <= HOST_BITS_PER_WIDE_INT) 4467169689Skan && GET_MODE_CLASS (inner_mode) == MODE_INT 4468169689Skan && (STORE_FLAG_VALUE 4469169689Skan & ((HOST_WIDE_INT) 1 4470169689Skan << (GET_MODE_BITSIZE (inner_mode) - 1)))) 4471169689Skan#ifdef FLOAT_STORE_FLAG_VALUE 4472169689Skan || (code == GE 4473169689Skan && SCALAR_FLOAT_MODE_P (inner_mode) 4474169689Skan && (fsfv = FLOAT_STORE_FLAG_VALUE (inner_mode), 4475169689Skan REAL_VALUE_NEGATIVE (fsfv))) 4476169689Skan#endif 4477169689Skan )) 4478169689Skan && COMPARISON_P (SET_SRC (set)) 4479169689Skan && (((GET_MODE_CLASS (mode) == MODE_CC) 4480169689Skan == (GET_MODE_CLASS (inner_mode) == MODE_CC)) 4481169689Skan || mode == VOIDmode || inner_mode == VOIDmode)) 4482169689Skan 4483169689Skan { 4484169689Skan reverse_code = 1; 4485169689Skan x = SET_SRC (set); 4486169689Skan } 4487169689Skan else 4488169689Skan break; 4489169689Skan } 4490169689Skan 4491169689Skan else if (reg_set_p (op0, prev)) 4492169689Skan /* If this sets OP0, but not directly, we have to give up. */ 4493169689Skan break; 4494169689Skan 4495169689Skan if (x) 4496169689Skan { 4497169689Skan /* If the caller is expecting the condition to be valid at INSN, 4498169689Skan make sure X doesn't change before INSN. */ 4499169689Skan if (valid_at_insn_p) 4500169689Skan if (modified_in_p (x, prev) || modified_between_p (x, prev, insn)) 4501169689Skan break; 4502169689Skan if (COMPARISON_P (x)) 4503169689Skan code = GET_CODE (x); 4504169689Skan if (reverse_code) 4505169689Skan { 4506169689Skan code = reversed_comparison_code (x, prev); 4507169689Skan if (code == UNKNOWN) 4508169689Skan return 0; 4509169689Skan reverse_code = 0; 4510169689Skan } 4511169689Skan 4512169689Skan op0 = XEXP (x, 0), op1 = XEXP (x, 1); 4513169689Skan if (earliest) 4514169689Skan *earliest = prev; 4515169689Skan } 4516117395Skan } 4517117395Skan 4518169689Skan /* If constant is first, put it last. */ 4519169689Skan if (CONSTANT_P (op0)) 4520169689Skan code = swap_condition (code), tem = op0, op0 = op1, op1 = tem; 4521117395Skan 4522169689Skan /* If OP0 is the result of a comparison, we weren't able to find what 4523169689Skan was really being compared, so fail. */ 4524169689Skan if (!allow_cc_mode 4525169689Skan && GET_MODE_CLASS (GET_MODE (op0)) == MODE_CC) 4526169689Skan return 0; 4527169689Skan 4528169689Skan /* Canonicalize any ordered comparison with integers involving equality 4529169689Skan if we can do computations in the relevant mode and we do not 4530169689Skan overflow. */ 4531169689Skan 4532169689Skan if (GET_MODE_CLASS (GET_MODE (op0)) != MODE_CC 4533169689Skan && GET_CODE (op1) == CONST_INT 4534169689Skan && GET_MODE (op0) != VOIDmode 4535169689Skan && GET_MODE_BITSIZE (GET_MODE (op0)) <= HOST_BITS_PER_WIDE_INT) 4536169689Skan { 4537169689Skan HOST_WIDE_INT const_val = INTVAL (op1); 4538169689Skan unsigned HOST_WIDE_INT uconst_val = const_val; 4539169689Skan unsigned HOST_WIDE_INT max_val 4540169689Skan = (unsigned HOST_WIDE_INT) GET_MODE_MASK (GET_MODE (op0)); 4541169689Skan 4542169689Skan switch (code) 4543169689Skan { 4544169689Skan case LE: 4545169689Skan if ((unsigned HOST_WIDE_INT) const_val != max_val >> 1) 4546169689Skan code = LT, op1 = gen_int_mode (const_val + 1, GET_MODE (op0)); 4547169689Skan break; 4548169689Skan 4549169689Skan /* When cross-compiling, const_val might be sign-extended from 4550169689Skan BITS_PER_WORD to HOST_BITS_PER_WIDE_INT */ 4551169689Skan case GE: 4552169689Skan if ((HOST_WIDE_INT) (const_val & max_val) 4553169689Skan != (((HOST_WIDE_INT) 1 4554169689Skan << (GET_MODE_BITSIZE (GET_MODE (op0)) - 1)))) 4555169689Skan code = GT, op1 = gen_int_mode (const_val - 1, GET_MODE (op0)); 4556169689Skan break; 4557169689Skan 4558169689Skan case LEU: 4559169689Skan if (uconst_val < max_val) 4560169689Skan code = LTU, op1 = gen_int_mode (uconst_val + 1, GET_MODE (op0)); 4561169689Skan break; 4562169689Skan 4563169689Skan case GEU: 4564169689Skan if (uconst_val != 0) 4565169689Skan code = GTU, op1 = gen_int_mode (uconst_val - 1, GET_MODE (op0)); 4566169689Skan break; 4567169689Skan 4568169689Skan default: 4569169689Skan break; 4570169689Skan } 4571169689Skan } 4572169689Skan 4573169689Skan /* Never return CC0; return zero instead. */ 4574169689Skan if (CC0_P (op0)) 4575169689Skan return 0; 4576169689Skan 4577169689Skan return gen_rtx_fmt_ee (code, VOIDmode, op0, op1); 4578117395Skan} 4579132718Skan 4580169689Skan/* Given a jump insn JUMP, return the condition that will cause it to branch 4581169689Skan to its JUMP_LABEL. If the condition cannot be understood, or is an 4582169689Skan inequality floating-point comparison which needs to be reversed, 0 will 4583169689Skan be returned. 4584132718Skan 4585169689Skan If EARLIEST is nonzero, it is a pointer to a place where the earliest 4586169689Skan insn used in locating the condition was found. If a replacement test 4587169689Skan of the condition is desired, it should be placed in front of that 4588169689Skan insn and we will be sure that the inputs are still valid. If EARLIEST 4589169689Skan is null, the returned condition will be valid at INSN. 4590169689Skan 4591169689Skan If ALLOW_CC_MODE is nonzero, allow the condition returned to be a 4592169689Skan compare CC mode register. 4593169689Skan 4594169689Skan VALID_AT_INSN_P is the same as for canonicalize_condition. */ 4595169689Skan 4596169689Skanrtx 4597169689Skanget_condition (rtx jump, rtx *earliest, int allow_cc_mode, int valid_at_insn_p) 4598169689Skan{ 4599169689Skan rtx cond; 4600169689Skan int reverse; 4601169689Skan rtx set; 4602169689Skan 4603169689Skan /* If this is not a standard conditional jump, we can't parse it. */ 4604169689Skan if (!JUMP_P (jump) 4605169689Skan || ! any_condjump_p (jump)) 4606169689Skan return 0; 4607169689Skan set = pc_set (jump); 4608169689Skan 4609169689Skan cond = XEXP (SET_SRC (set), 0); 4610169689Skan 4611169689Skan /* If this branches to JUMP_LABEL when the condition is false, reverse 4612169689Skan the condition. */ 4613169689Skan reverse 4614169689Skan = GET_CODE (XEXP (SET_SRC (set), 2)) == LABEL_REF 4615169689Skan && XEXP (XEXP (SET_SRC (set), 2), 0) == JUMP_LABEL (jump); 4616169689Skan 4617169689Skan return canonicalize_condition (jump, cond, reverse, earliest, NULL_RTX, 4618169689Skan allow_cc_mode, valid_at_insn_p); 4619169689Skan} 4620169689Skan 4621169689Skan/* Initialize the table NUM_SIGN_BIT_COPIES_IN_REP based on 4622169689Skan TARGET_MODE_REP_EXTENDED. 4623169689Skan 4624169689Skan Note that we assume that the property of 4625169689Skan TARGET_MODE_REP_EXTENDED(B, C) is sticky to the integral modes 4626169689Skan narrower than mode B. I.e., if A is a mode narrower than B then in 4627169689Skan order to be able to operate on it in mode B, mode A needs to 4628169689Skan satisfy the requirements set by the representation of mode B. */ 4629169689Skan 4630169689Skanstatic void 4631169689Skaninit_num_sign_bit_copies_in_rep (void) 4632169689Skan{ 4633169689Skan enum machine_mode mode, in_mode; 4634169689Skan 4635169689Skan for (in_mode = GET_CLASS_NARROWEST_MODE (MODE_INT); in_mode != VOIDmode; 4636169689Skan in_mode = GET_MODE_WIDER_MODE (mode)) 4637169689Skan for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT); mode != in_mode; 4638169689Skan mode = GET_MODE_WIDER_MODE (mode)) 4639169689Skan { 4640169689Skan enum machine_mode i; 4641169689Skan 4642169689Skan /* Currently, it is assumed that TARGET_MODE_REP_EXTENDED 4643169689Skan extends to the next widest mode. */ 4644169689Skan gcc_assert (targetm.mode_rep_extended (mode, in_mode) == UNKNOWN 4645169689Skan || GET_MODE_WIDER_MODE (mode) == in_mode); 4646169689Skan 4647169689Skan /* We are in in_mode. Count how many bits outside of mode 4648169689Skan have to be copies of the sign-bit. */ 4649169689Skan for (i = mode; i != in_mode; i = GET_MODE_WIDER_MODE (i)) 4650169689Skan { 4651169689Skan enum machine_mode wider = GET_MODE_WIDER_MODE (i); 4652169689Skan 4653169689Skan if (targetm.mode_rep_extended (i, wider) == SIGN_EXTEND 4654169689Skan /* We can only check sign-bit copies starting from the 4655169689Skan top-bit. In order to be able to check the bits we 4656169689Skan have already seen we pretend that subsequent bits 4657169689Skan have to be sign-bit copies too. */ 4658169689Skan || num_sign_bit_copies_in_rep [in_mode][mode]) 4659169689Skan num_sign_bit_copies_in_rep [in_mode][mode] 4660169689Skan += GET_MODE_BITSIZE (wider) - GET_MODE_BITSIZE (i); 4661169689Skan } 4662169689Skan } 4663169689Skan} 4664169689Skan 4665169689Skan/* Suppose that truncation from the machine mode of X to MODE is not a 4666169689Skan no-op. See if there is anything special about X so that we can 4667169689Skan assume it already contains a truncated value of MODE. */ 4668169689Skan 4669132718Skanbool 4670169689Skantruncated_to_mode (enum machine_mode mode, rtx x) 4671132718Skan{ 4672169689Skan /* This register has already been used in MODE without explicit 4673169689Skan truncation. */ 4674169689Skan if (REG_P (x) && rtl_hooks.reg_truncated_to_mode (mode, x)) 4675169689Skan return true; 4676132718Skan 4677169689Skan /* See if we already satisfy the requirements of MODE. If yes we 4678169689Skan can just switch to MODE. */ 4679169689Skan if (num_sign_bit_copies_in_rep[GET_MODE (x)][mode] 4680169689Skan && (num_sign_bit_copies (x, GET_MODE (x)) 4681169689Skan >= num_sign_bit_copies_in_rep[GET_MODE (x)][mode] + 1)) 4682132718Skan return true; 4683132718Skan 4684169689Skan return false; 4685169689Skan} 4686169689Skan 4687169689Skan/* Initialize non_rtx_starting_operands, which is used to speed up 4688169689Skan for_each_rtx. */ 4689169689Skanvoid 4690169689Skaninit_rtlanal (void) 4691169689Skan{ 4692169689Skan int i; 4693169689Skan for (i = 0; i < NUM_RTX_CODE; i++) 4694132718Skan { 4695169689Skan const char *format = GET_RTX_FORMAT (i); 4696169689Skan const char *first = strpbrk (format, "eEV"); 4697169689Skan non_rtx_starting_operands[i] = first ? first - format : -1; 4698132718Skan } 4699132718Skan 4700169689Skan init_num_sign_bit_copies_in_rep (); 4701132718Skan} 4702169689Skan 4703169689Skan/* Check whether this is a constant pool constant. */ 4704169689Skanbool 4705169689Skanconstant_pool_constant_p (rtx x) 4706169689Skan{ 4707169689Skan x = avoid_constant_pool_reference (x); 4708169689Skan return GET_CODE (x) == CONST_DOUBLE; 4709169689Skan} 4710132718Skan 4711