reload.h revision 50397
1/* Communication between reload.c and reload1.c. 2 Copyright (C) 1987, 91-95, 97, 1998 Free Software Foundation, Inc. 3 4This file is part of GNU CC. 5 6GNU CC is free software; you can redistribute it and/or modify 7it under the terms of the GNU General Public License as published by 8the Free Software Foundation; either version 2, or (at your option) 9any later version. 10 11GNU CC is distributed in the hope that it will be useful, 12but WITHOUT ANY WARRANTY; without even the implied warranty of 13MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14GNU General Public License for more details. 15 16You should have received a copy of the GNU General Public License 17along with GNU CC; see the file COPYING. If not, write to 18the Free Software Foundation, 59 Temple Place - Suite 330, 19Boston, MA 02111-1307, USA. */ 20 21 22/* If secondary reloads are the same for inputs and outputs, define those 23 macros here. */ 24 25#ifdef SECONDARY_RELOAD_CLASS 26#define SECONDARY_INPUT_RELOAD_CLASS(CLASS, MODE, X) \ 27 SECONDARY_RELOAD_CLASS (CLASS, MODE, X) 28#define SECONDARY_OUTPUT_RELOAD_CLASS(CLASS, MODE, X) \ 29 SECONDARY_RELOAD_CLASS (CLASS, MODE, X) 30#endif 31 32/* If either macro is defined, show that we need secondary reloads. */ 33#if defined(SECONDARY_INPUT_RELOAD_CLASS) || defined(SECONDARY_OUTPUT_RELOAD_CLASS) 34#define HAVE_SECONDARY_RELOADS 35#endif 36 37/* If MEMORY_MOVE_COST isn't defined, give it a default here. */ 38#ifndef MEMORY_MOVE_COST 39#ifdef HAVE_SECONDARY_RELOADS 40#define MEMORY_MOVE_COST(MODE,CLASS,IN) \ 41 (4 + memory_move_secondary_cost ((MODE), (CLASS), (IN))) 42#else 43#define MEMORY_MOVE_COST(MODE,CLASS,IN) 4 44#endif 45#endif 46extern int memory_move_secondary_cost PROTO ((enum machine_mode, enum reg_class, int)); 47 48/* See reload.c and reload1.c for comments on these variables. */ 49 50/* Maximum number of reloads we can need. */ 51#define MAX_RELOADS (2 * MAX_RECOG_OPERANDS * (MAX_REGS_PER_ADDRESS + 1)) 52 53extern enum reg_class reload_address_base_reg_class; 54extern enum reg_class reload_address_index_reg_class; 55extern rtx reload_in[MAX_RELOADS]; 56extern rtx reload_out[MAX_RELOADS]; 57extern rtx reload_in_reg[MAX_RELOADS]; 58extern enum reg_class reload_reg_class[MAX_RELOADS]; 59extern enum machine_mode reload_inmode[MAX_RELOADS]; 60extern enum machine_mode reload_outmode[MAX_RELOADS]; 61extern char reload_optional[MAX_RELOADS]; 62extern char reload_nongroup[MAX_RELOADS]; 63extern int reload_inc[MAX_RELOADS]; 64extern int reload_opnum[MAX_RELOADS]; 65extern int reload_secondary_p[MAX_RELOADS]; 66extern int reload_secondary_in_reload[MAX_RELOADS]; 67extern int reload_secondary_out_reload[MAX_RELOADS]; 68#ifdef MAX_INSN_CODE 69extern enum insn_code reload_secondary_in_icode[MAX_RELOADS]; 70extern enum insn_code reload_secondary_out_icode[MAX_RELOADS]; 71#endif 72extern int n_reloads; 73 74extern rtx reload_reg_rtx[MAX_RELOADS]; 75 76/* Encode the usage of a reload. The following codes are supported: 77 78 RELOAD_FOR_INPUT reload of an input operand 79 RELOAD_FOR_OUTPUT likewise, for output 80 RELOAD_FOR_INSN a reload that must not conflict with anything 81 used in the insn, but may conflict with 82 something used before or after the insn 83 RELOAD_FOR_INPUT_ADDRESS reload for parts of the address of an object 84 that is an input reload 85 RELOAD_FOR_INPADDR_ADDRESS reload needed for RELOAD_FOR_INPUT_ADDRESS 86 RELOAD_FOR_OUTPUT_ADDRESS like RELOAD_FOR INPUT_ADDRESS, for output 87 RELOAD_FOR_OUTADDR_ADDRESS reload needed for RELOAD_FOR_OUTPUT_ADDRESS 88 RELOAD_FOR_OPERAND_ADDRESS reload for the address of a non-reloaded 89 operand; these don't conflict with 90 any other addresses. 91 RELOAD_FOR_OPADDR_ADDR reload needed for RELOAD_FOR_OPERAND_ADDRESS 92 reloads; usually secondary reloads 93 RELOAD_OTHER none of the above, usually multiple uses 94 RELOAD_FOR_OTHER_ADDRESS reload for part of the address of an input 95 that is marked RELOAD_OTHER. 96 97 This used to be "enum reload_when_needed" but some debuggers have trouble 98 with an enum tag and variable of the same name. */ 99 100enum reload_type 101{ 102 RELOAD_FOR_INPUT, RELOAD_FOR_OUTPUT, RELOAD_FOR_INSN, 103 RELOAD_FOR_INPUT_ADDRESS, RELOAD_FOR_INPADDR_ADDRESS, 104 RELOAD_FOR_OUTPUT_ADDRESS, RELOAD_FOR_OUTADDR_ADDRESS, 105 RELOAD_FOR_OPERAND_ADDRESS, RELOAD_FOR_OPADDR_ADDR, 106 RELOAD_OTHER, RELOAD_FOR_OTHER_ADDRESS 107}; 108 109extern enum reload_type reload_when_needed[MAX_RELOADS]; 110 111extern rtx *reg_equiv_constant; 112extern rtx *reg_equiv_memory_loc; 113extern rtx *reg_equiv_address; 114extern rtx *reg_equiv_mem; 115 116/* All the "earlyclobber" operands of the current insn 117 are recorded here. */ 118extern int n_earlyclobbers; 119extern rtx reload_earlyclobbers[MAX_RECOG_OPERANDS]; 120 121/* Save the number of operands. */ 122extern int reload_n_operands; 123 124/* First uid used by insns created by reload in this function. 125 Used in find_equiv_reg. */ 126extern int reload_first_uid; 127 128/* Nonzero if indirect addressing is supported when the innermost MEM is 129 of the form (MEM (SYMBOL_REF sym)). It is assumed that the level to 130 which these are valid is the same as spill_indirect_levels, above. */ 131 132extern char indirect_symref_ok; 133 134/* Nonzero if an address (plus (reg frame_pointer) (reg ...)) is valid. */ 135extern char double_reg_address_ok; 136 137#ifdef MAX_INSN_CODE 138/* These arrays record the insn_code of insns that may be needed to 139 perform input and output reloads of special objects. They provide a 140 place to pass a scratch register. */ 141extern enum insn_code reload_in_optab[]; 142extern enum insn_code reload_out_optab[]; 143#endif 144 145/* Functions from reload.c: */ 146 147/* Return a memory location that will be used to copy X in mode MODE. 148 If we haven't already made a location for this mode in this insn, 149 call find_reloads_address on the location being returned. */ 150extern rtx get_secondary_mem PROTO((rtx, enum machine_mode, 151 int, enum reload_type)); 152 153/* Clear any secondary memory locations we've made. */ 154extern void clear_secondary_mem PROTO((void)); 155 156/* Transfer all replacements that used to be in reload FROM to be in 157 reload TO. */ 158extern void transfer_replacements PROTO((int, int)); 159 160/* Remove all replacements in reload FROM. */ 161extern void remove_replacements PROTO((int)); 162 163/* Like rtx_equal_p except that it allows a REG and a SUBREG to match 164 if they are the same hard reg, and has special hacks for 165 autoincrement and autodecrement. */ 166extern int operands_match_p PROTO((rtx, rtx)); 167 168/* Return the number of times character C occurs in string S. */ 169extern int n_occurrences PROTO((int, char *)); 170 171/* Return 1 if altering OP will not modify the value of CLOBBER. */ 172extern int safe_from_earlyclobber PROTO((rtx, rtx)); 173 174/* Search the body of INSN for values that need reloading and record them 175 with push_reload. REPLACE nonzero means record also where the values occur 176 so that subst_reloads can be used. */ 177extern void find_reloads PROTO((rtx, int, int, int, short *)); 178 179/* Compute the sum of X and Y, making canonicalizations assumed in an 180 address, namely: sum constant integers, surround the sum of two 181 constants with a CONST, put the constant as the second operand, and 182 group the constant on the outermost sum. */ 183extern rtx form_sum PROTO((rtx, rtx)); 184 185/* Substitute into the current INSN the registers into which we have reloaded 186 the things that need reloading. */ 187extern void subst_reloads PROTO((void)); 188 189/* Make a copy of any replacements being done into X and move those copies 190 to locations in Y, a copy of X. We only look at the highest level of 191 the RTL. */ 192extern void copy_replacements PROTO((rtx, rtx)); 193 194/* Change any replacements being done to *X to be done to *Y */ 195extern void move_replacements PROTO((rtx *x, rtx *y)); 196 197/* If LOC was scheduled to be replaced by something, return the replacement. 198 Otherwise, return *LOC. */ 199extern rtx find_replacement PROTO((rtx *)); 200 201/* Return nonzero if register in range [REGNO, ENDREGNO) 202 appears either explicitly or implicitly in X 203 other than being stored into. */ 204extern int refers_to_regno_for_reload_p PROTO((int, int, rtx, rtx *)); 205 206/* Nonzero if modifying X will affect IN. */ 207extern int reg_overlap_mentioned_for_reload_p PROTO((rtx, rtx)); 208 209/* Return nonzero if anything in X contains a MEM. Look also for pseudo 210 registers. */ 211extern int refers_to_mem_for_reload_p PROTO((rtx)); 212 213/* Check the insns before INSN to see if there is a suitable register 214 containing the same value as GOAL. */ 215extern rtx find_equiv_reg PROTO((rtx, rtx, enum reg_class, int, short *, 216 int, enum machine_mode)); 217 218/* Return 1 if register REGNO is the subject of a clobber in insn INSN. */ 219extern int regno_clobbered_p PROTO((int, rtx)); 220 221/* Functions in reload1.c: */ 222 223extern int reloads_conflict PROTO ((int, int)); 224 225int count_occurrences PROTO((rtx, rtx)); 226 227/* Initialize the reload pass once per compilation. */ 228extern void init_reload PROTO((void)); 229 230/* The reload pass itself. */ 231extern int reload PROTO((rtx, int, FILE *)); 232 233/* Mark the slots in regs_ever_live for the hard regs 234 used by pseudo-reg number REGNO. */ 235extern void mark_home_live PROTO((int)); 236 237/* Scan X and replace any eliminable registers (such as fp) with a 238 replacement (such as sp), plus an offset. */ 239extern rtx eliminate_regs PROTO((rtx, enum machine_mode, rtx)); 240 241/* Emit code to perform a reload from IN (which may be a reload register) to 242 OUT (which may also be a reload register). IN or OUT is from operand 243 OPNUM with reload type TYPE. */ 244extern rtx gen_reload PROTO((rtx, rtx, int, enum reload_type)); 245 246/* Functions in caller-save.c: */ 247 248/* Initialize for caller-save. */ 249extern void init_caller_save PROTO((void)); 250 251/* Initialize save areas by showing that we haven't allocated any yet. */ 252extern void init_save_areas PROTO((void)); 253 254/* Allocate save areas for any hard registers that might need saving. */ 255extern int setup_save_areas PROTO((int *)); 256 257/* Find the places where hard regs are live across calls and save them. */ 258extern void save_call_clobbered_regs PROTO((enum machine_mode)); 259