1/* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998
3 1999, 2000, 2001 Free Software Foundation, Inc.
4
5This file is part of GCC.
6
7GCC is free software; you can redistribute it and/or modify it under
8the terms of the GNU General Public License as published by the Free
9Software Foundation; either version 2, or (at your option) any later
10version.
11
12GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13WARRANTY; without even the implied warranty of MERCHANTABILITY or
14FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15for more details.
16
17You should have received a copy of the GNU General Public License
18along with GCC; see the file COPYING. If not, write to the Free
19Software Foundation, 59 Temple Place - Suite 330, Boston, MA
2002111-1307, USA. */
21
22#include "config.h"
23#include "system.h"
24#include "rtl.h"
25#include "tree.h"
26#include "flags.h"
27#include "expr.h"
28#include "libfuncs.h"
29#include "function.h"
30#include "regs.h"
31#include "toplev.h"
32#include "output.h"
33#include "tm_p.h"
34#include "timevar.h"
35#include "sbitmap.h"
36
37#if !defined FUNCTION_OK_FOR_SIBCALL
38#define FUNCTION_OK_FOR_SIBCALL(DECL) 1
39#endif
40
41/* Decide whether a function's arguments should be processed
42 from first to last or from last to first.
43
44 They should if the stack and args grow in opposite directions, but
45 only if we have push insns. */
46
47#ifdef PUSH_ROUNDING
48
49#if defined (STACK_GROWS_DOWNWARD) != defined (ARGS_GROW_DOWNWARD)
50#define PUSH_ARGS_REVERSED PUSH_ARGS
51#endif
52
53#endif
54
55#ifndef PUSH_ARGS_REVERSED
56#define PUSH_ARGS_REVERSED 0
57#endif
58
59#ifndef STACK_POINTER_OFFSET
60#define STACK_POINTER_OFFSET 0
61#endif
62
63/* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
64#define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
65
66/* Data structure and subroutines used within expand_call. */
67
68struct arg_data
69{
70 /* Tree node for this argument. */
71 tree tree_value;
72 /* Mode for value; TYPE_MODE unless promoted. */
73 enum machine_mode mode;
74 /* Current RTL value for argument, or 0 if it isn't precomputed. */
75 rtx value;
76 /* Initially-compute RTL value for argument; only for const functions. */
77 rtx initial_value;
78 /* Register to pass this argument in, 0 if passed on stack, or an
79 PARALLEL if the arg is to be copied into multiple non-contiguous
80 registers. */
81 rtx reg;
82 /* Register to pass this argument in when generating tail call sequence.
83 This is not the same register as for normal calls on machines with
84 register windows. */
85 rtx tail_call_reg;
86 /* If REG was promoted from the actual mode of the argument expression,
87 indicates whether the promotion is sign- or zero-extended. */
88 int unsignedp;
89 /* Number of registers to use. 0 means put the whole arg in registers.
90 Also 0 if not passed in registers. */
91 int partial;
92 /* Non-zero if argument must be passed on stack.
93 Note that some arguments may be passed on the stack
94 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
95 pass_on_stack identifies arguments that *cannot* go in registers. */
96 int pass_on_stack;
97 /* Offset of this argument from beginning of stack-args. */
98 struct args_size offset;
99 /* Similar, but offset to the start of the stack slot. Different from
100 OFFSET if this arg pads downward. */
101 struct args_size slot_offset;
102 /* Size of this argument on the stack, rounded up for any padding it gets,
103 parts of the argument passed in registers do not count.
104 If REG_PARM_STACK_SPACE is defined, then register parms
105 are counted here as well. */
106 struct args_size size;
107 /* Location on the stack at which parameter should be stored. The store
108 has already been done if STACK == VALUE. */
109 rtx stack;
110 /* Location on the stack of the start of this argument slot. This can
111 differ from STACK if this arg pads downward. This location is known
112 to be aligned to FUNCTION_ARG_BOUNDARY. */
113 rtx stack_slot;
114 /* Place that this stack area has been saved, if needed. */
115 rtx save_area;
116 /* If an argument's alignment does not permit direct copying into registers,
117 copy in smaller-sized pieces into pseudos. These are stored in a
118 block pointed to by this field. The next field says how many
119 word-sized pseudos we made. */
120 rtx *aligned_regs;
121 int n_aligned_regs;
122 /* The amount that the stack pointer needs to be adjusted to
123 force alignment for the next argument. */
124 struct args_size alignment_pad;
125};
126
127/* A vector of one char per byte of stack space. A byte if non-zero if
128 the corresponding stack location has been used.
129 This vector is used to prevent a function call within an argument from
130 clobbering any stack already set up. */
131static char *stack_usage_map;
132
133/* Size of STACK_USAGE_MAP. */
134static int highest_outgoing_arg_in_use;
135
136/* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
137 stack location's tail call argument has been already stored into the stack.
138 This bitmap is used to prevent sibling call optimization if function tries
139 to use parent's incoming argument slots when they have been already
140 overwritten with tail call arguments. */
141static sbitmap stored_args_map;
142
143/* stack_arg_under_construction is nonzero when an argument may be
144 initialized with a constructor call (including a C function that
145 returns a BLKmode struct) and expand_call must take special action
146 to make sure the object being constructed does not overlap the
147 argument list for the constructor call. */
148int stack_arg_under_construction;
149
150static int calls_function PARAMS ((tree, int));
151static int calls_function_1 PARAMS ((tree, int));
152
153/* Nonzero if this is a call to a `const' function. */
154#define ECF_CONST 1
155/* Nonzero if this is a call to a `volatile' function. */
156#define ECF_NORETURN 2
157/* Nonzero if this is a call to malloc or a related function. */
158#define ECF_MALLOC 4
159/* Nonzero if it is plausible that this is a call to alloca. */
160#define ECF_MAY_BE_ALLOCA 8
161/* Nonzero if this is a call to a function that won't throw an exception. */
162#define ECF_NOTHROW 16
163/* Nonzero if this is a call to setjmp or a related function. */
164#define ECF_RETURNS_TWICE 32
165/* Nonzero if this is a call to `longjmp'. */
166#define ECF_LONGJMP 64
167/* Nonzero if this is a syscall that makes a new process in the image of
168 the current one. */
169#define ECF_FORK_OR_EXEC 128
170#define ECF_SIBCALL 256
171/* Nonzero if this is a call to "pure" function (like const function,
172 but may read memory. */
173#define ECF_PURE 512
174/* Nonzero if this is a call to a function that returns with the stack
175 pointer depressed. */
176#define ECF_SP_DEPRESSED 1024
177/* Nonzero if this call is known to always return. */
178#define ECF_ALWAYS_RETURN 2048
179/* Create libcall block around the call. */
180#define ECF_LIBCALL_BLOCK 4096
181
182static void emit_call_1 PARAMS ((rtx, tree, tree, HOST_WIDE_INT,
183 HOST_WIDE_INT, HOST_WIDE_INT, rtx,
184 rtx, int, rtx, int,
185 CUMULATIVE_ARGS *));
186static void precompute_register_parameters PARAMS ((int,
187 struct arg_data *,
188 int *));
189static int store_one_arg PARAMS ((struct arg_data *, rtx, int, int,
190 int));
191static void store_unaligned_arguments_into_pseudos PARAMS ((struct arg_data *,
192 int));
193static int finalize_must_preallocate PARAMS ((int, int,
194 struct arg_data *,
195 struct args_size *));
196static void precompute_arguments PARAMS ((int, int,
197 struct arg_data *));
198static int compute_argument_block_size PARAMS ((int,
199 struct args_size *,
200 int));
201static void initialize_argument_information PARAMS ((int,
202 struct arg_data *,
203 struct args_size *,
204 int, tree, tree,
205 CUMULATIVE_ARGS *,
206 int, rtx *, int *,
207 int *, int *));
208static void compute_argument_addresses PARAMS ((struct arg_data *,
209 rtx, int));
210static rtx rtx_for_function_call PARAMS ((tree, tree));
211static void load_register_parameters PARAMS ((struct arg_data *,
212 int, rtx *, int));
213static rtx emit_library_call_value_1 PARAMS ((int, rtx, rtx,
214 enum libcall_type,
215 enum machine_mode,
216 int, va_list));
217static int special_function_p PARAMS ((tree, int));
218static int flags_from_decl_or_type PARAMS ((tree));
219static rtx try_to_integrate PARAMS ((tree, tree, rtx,
220 int, tree, rtx));
221static int check_sibcall_argument_overlap_1 PARAMS ((rtx));
222static int check_sibcall_argument_overlap PARAMS ((rtx, struct arg_data *));
223
224static int combine_pending_stack_adjustment_and_call
225 PARAMS ((int, struct args_size *, int));
226
227#ifdef REG_PARM_STACK_SPACE
228static rtx save_fixed_argument_area PARAMS ((int, rtx, int *, int *));
229static void restore_fixed_argument_area PARAMS ((rtx, rtx, int, int));
230#endif
231
232/* If WHICH is 1, return 1 if EXP contains a call to the built-in function
233 `alloca'.
234
235 If WHICH is 0, return 1 if EXP contains a call to any function.
236 Actually, we only need return 1 if evaluating EXP would require pushing
237 arguments on the stack, but that is too difficult to compute, so we just
238 assume any function call might require the stack. */
239
240static tree calls_function_save_exprs;
241
242static int
243calls_function (exp, which)
244 tree exp;
245 int which;
246{
247 int val;
248
249 calls_function_save_exprs = 0;
250 val = calls_function_1 (exp, which);
251 calls_function_save_exprs = 0;
252 return val;
253}
254
255/* Recursive function to do the work of above function. */
256
257static int
258calls_function_1 (exp, which)
259 tree exp;
260 int which;
261{
262 int i;
263 enum tree_code code = TREE_CODE (exp);
264 int class = TREE_CODE_CLASS (code);
265 int length = first_rtl_op (code);
266
267 /* If this code is language-specific, we don't know what it will do. */
268 if ((int) code >= NUM_TREE_CODES)
269 return 1;
270
271 switch (code)
272 {
273 case CALL_EXPR:
274 if (which == 0)
275 return 1;
276 else if ((TREE_CODE (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))
277 == FUNCTION_TYPE)
278 && (TYPE_RETURNS_STACK_DEPRESSED
279 (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))))
280 return 1;
281 else if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
282 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
283 == FUNCTION_DECL)
284 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp, 0), 0),
285 0)
286 & ECF_MAY_BE_ALLOCA))
287 return 1;
288
289 break;
290
291 case CONSTRUCTOR:
292 {
293 tree tem;
294
295 for (tem = CONSTRUCTOR_ELTS (exp); tem != 0; tem = TREE_CHAIN (tem))
296 if (calls_function_1 (TREE_VALUE (tem), which))
297 return 1;
298 }
299
300 return 0;
301
302 case SAVE_EXPR:
303 if (SAVE_EXPR_RTL (exp) != 0)
304 return 0;
305 if (value_member (exp, calls_function_save_exprs))
306 return 0;
307 calls_function_save_exprs = tree_cons (NULL_TREE, exp,
308 calls_function_save_exprs);
309 return (TREE_OPERAND (exp, 0) != 0
310 && calls_function_1 (TREE_OPERAND (exp, 0), which));
311
312 case BLOCK:
313 {
314 tree local;
315 tree subblock;
316
317 for (local = BLOCK_VARS (exp); local; local = TREE_CHAIN (local))
318 if (DECL_INITIAL (local) != 0
319 && calls_function_1 (DECL_INITIAL (local), which))
320 return 1;
321
322 for (subblock = BLOCK_SUBBLOCKS (exp);
323 subblock;
324 subblock = TREE_CHAIN (subblock))
325 if (calls_function_1 (subblock, which))
326 return 1;
327 }
328 return 0;
329
330 case TREE_LIST:
331 for (; exp != 0; exp = TREE_CHAIN (exp))
332 if (calls_function_1 (TREE_VALUE (exp), which))
333 return 1;
334 return 0;
335
336 default:
337 break;
338 }
339
340 /* Only expressions, references, and blocks can contain calls. */
341 if (! IS_EXPR_CODE_CLASS (class) && class != 'r' && class != 'b')
342 return 0;
343
344 for (i = 0; i < length; i++)
345 if (TREE_OPERAND (exp, i) != 0
346 && calls_function_1 (TREE_OPERAND (exp, i), which))
347 return 1;
348
349 return 0;
350}
351
352/* Force FUNEXP into a form suitable for the address of a CALL,
353 and return that as an rtx. Also load the static chain register
354 if FNDECL is a nested function.
355
356 CALL_FUSAGE points to a variable holding the prospective
357 CALL_INSN_FUNCTION_USAGE information. */
358
359rtx
360prepare_call_address (funexp, fndecl, call_fusage, reg_parm_seen, sibcallp)
361 rtx funexp;
362 tree fndecl;
363 rtx *call_fusage;
364 int reg_parm_seen;
365 int sibcallp;
366{
367 rtx static_chain_value = 0;
368
369 funexp = protect_from_queue (funexp, 0);
370
371 if (fndecl != 0)
372 /* Get possible static chain value for nested function in C. */
373 static_chain_value = lookup_static_chain (fndecl);
374
375 /* Make a valid memory address and copy constants thru pseudo-regs,
376 but not for a constant address if -fno-function-cse. */
377 if (GET_CODE (funexp) != SYMBOL_REF)
378 /* If we are using registers for parameters, force the
379 function address into a register now. */
380 funexp = ((SMALL_REGISTER_CLASSES && reg_parm_seen)
381 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
382 : memory_address (FUNCTION_MODE, funexp));
383 else if (! sibcallp)
384 {
385#ifndef NO_FUNCTION_CSE
386 if (optimize && ! flag_no_function_cse)
387#ifdef NO_RECURSIVE_FUNCTION_CSE
388 if (fndecl != current_function_decl)
389#endif
390 funexp = force_reg (Pmode, funexp);
391#endif
392 }
393
394 if (static_chain_value != 0)
395 {
396 emit_move_insn (static_chain_rtx, static_chain_value);
397
398 if (GET_CODE (static_chain_rtx) == REG)
399 use_reg (call_fusage, static_chain_rtx);
400 }
401
402 return funexp;
403}
404
405/* Generate instructions to call function FUNEXP,
406 and optionally pop the results.
407 The CALL_INSN is the first insn generated.
408
409 FNDECL is the declaration node of the function. This is given to the
410 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
411
412 FUNTYPE is the data type of the function. This is given to the macro
413 RETURN_POPS_ARGS to determine whether this function pops its own args.
414 We used to allow an identifier for library functions, but that doesn't
415 work when the return type is an aggregate type and the calling convention
416 says that the pointer to this aggregate is to be popped by the callee.
417
418 STACK_SIZE is the number of bytes of arguments on the stack,
419 ROUNDED_STACK_SIZE is that number rounded up to
420 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
421 both to put into the call insn and to generate explicit popping
422 code if necessary.
423
424 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
425 It is zero if this call doesn't want a structure value.
426
427 NEXT_ARG_REG is the rtx that results from executing
428 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
429 just after all the args have had their registers assigned.
430 This could be whatever you like, but normally it is the first
431 arg-register beyond those used for args in this call,
432 or 0 if all the arg-registers are used in this call.
433 It is passed on to `gen_call' so you can put this info in the call insn.
434
435 VALREG is a hard register in which a value is returned,
436 or 0 if the call does not return a value.
437
438 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
439 the args to this call were processed.
440 We restore `inhibit_defer_pop' to that value.
441
442 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
443 denote registers used by the called function. */
444
445static void
446emit_call_1 (funexp, fndecl, funtype, stack_size, rounded_stack_size,
447 struct_value_size, next_arg_reg, valreg, old_inhibit_defer_pop,
448 call_fusage, ecf_flags, args_so_far)
449 rtx funexp;
450 tree fndecl ATTRIBUTE_UNUSED;
451 tree funtype ATTRIBUTE_UNUSED;
452 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED;
453 HOST_WIDE_INT rounded_stack_size;
454 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED;
455 rtx next_arg_reg ATTRIBUTE_UNUSED;
456 rtx valreg;
457 int old_inhibit_defer_pop;
458 rtx call_fusage;
459 int ecf_flags;
460 CUMULATIVE_ARGS *args_so_far ATTRIBUTE_UNUSED;
461{
462 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
463 rtx call_insn;
464 int already_popped = 0;
465 HOST_WIDE_INT n_popped = RETURN_POPS_ARGS (fndecl, funtype, stack_size);
466#if defined (HAVE_call) && defined (HAVE_call_value)
467 rtx struct_value_size_rtx;
468 struct_value_size_rtx = GEN_INT (struct_value_size);
469#endif
470
471#ifdef CALL_POPS_ARGS
472 n_popped += CALL_POPS_ARGS (* args_so_far);
473#endif
474
475 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
476 and we don't want to load it into a register as an optimization,
477 because prepare_call_address already did it if it should be done. */
478 if (GET_CODE (funexp) != SYMBOL_REF)
479 funexp = memory_address (FUNCTION_MODE, funexp);
480
481#if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
482 if ((ecf_flags & ECF_SIBCALL)
483 && HAVE_sibcall_pop && HAVE_sibcall_value_pop
484 && (n_popped > 0 || stack_size == 0))
485 {
486 rtx n_pop = GEN_INT (n_popped);
487 rtx pat;
488
489 /* If this subroutine pops its own args, record that in the call insn
490 if possible, for the sake of frame pointer elimination. */
491
492 if (valreg)
493 pat = GEN_SIBCALL_VALUE_POP (valreg,
494 gen_rtx_MEM (FUNCTION_MODE, funexp),
495 rounded_stack_size_rtx, next_arg_reg,
496 n_pop);
497 else
498 pat = GEN_SIBCALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
499 rounded_stack_size_rtx, next_arg_reg, n_pop);
500
501 emit_call_insn (pat);
502 already_popped = 1;
503 }
504 else
505#endif
506
507#if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
508 /* If the target has "call" or "call_value" insns, then prefer them
509 if no arguments are actually popped. If the target does not have
510 "call" or "call_value" insns, then we must use the popping versions
511 even if the call has no arguments to pop. */
512#if defined (HAVE_call) && defined (HAVE_call_value)
513 if (HAVE_call && HAVE_call_value && HAVE_call_pop && HAVE_call_value_pop
514 && n_popped > 0 && ! (ecf_flags & ECF_SP_DEPRESSED))
515#else
516 if (HAVE_call_pop && HAVE_call_value_pop)
517#endif
518 {
519 rtx n_pop = GEN_INT (n_popped);
520 rtx pat;
521
522 /* If this subroutine pops its own args, record that in the call insn
523 if possible, for the sake of frame pointer elimination. */
524
525 if (valreg)
526 pat = GEN_CALL_VALUE_POP (valreg,
527 gen_rtx_MEM (FUNCTION_MODE, funexp),
528 rounded_stack_size_rtx, next_arg_reg, n_pop);
529 else
530 pat = GEN_CALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
531 rounded_stack_size_rtx, next_arg_reg, n_pop);
532
533 emit_call_insn (pat);
534 already_popped = 1;
535 }
536 else
537#endif
538
539#if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
540 if ((ecf_flags & ECF_SIBCALL)
541 && HAVE_sibcall && HAVE_sibcall_value)
542 {
543 if (valreg)
544 emit_call_insn (GEN_SIBCALL_VALUE (valreg,
545 gen_rtx_MEM (FUNCTION_MODE, funexp),
546 rounded_stack_size_rtx,
547 next_arg_reg, NULL_RTX));
548 else
549 emit_call_insn (GEN_SIBCALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
550 rounded_stack_size_rtx, next_arg_reg,
551 struct_value_size_rtx));
552 }
553 else
554#endif
555
556#if defined (HAVE_call) && defined (HAVE_call_value)
557 if (HAVE_call && HAVE_call_value)
558 {
559 if (valreg)
560 emit_call_insn (GEN_CALL_VALUE (valreg,
561 gen_rtx_MEM (FUNCTION_MODE, funexp),
562 rounded_stack_size_rtx, next_arg_reg,
563 NULL_RTX));
564 else
565 emit_call_insn (GEN_CALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
566 rounded_stack_size_rtx, next_arg_reg,
567 struct_value_size_rtx));
568 }
569 else
570#endif
571 abort ();
572
573 /* Find the CALL insn we just emitted. */
574 for (call_insn = get_last_insn ();
575 call_insn && GET_CODE (call_insn) != CALL_INSN;
576 call_insn = PREV_INSN (call_insn))
577 ;
578
579 if (! call_insn)
580 abort ();
581
582 /* Mark memory as used for "pure" function call. */
583 if (ecf_flags & ECF_PURE)
584 call_fusage
585 = gen_rtx_EXPR_LIST
586 (VOIDmode,
587 gen_rtx_USE (VOIDmode,
588 gen_rtx_MEM (BLKmode, gen_rtx_SCRATCH (VOIDmode))),
589 call_fusage);
590
591 /* Put the register usage information on the CALL. If there is already
592 some usage information, put ours at the end. */
593 if (CALL_INSN_FUNCTION_USAGE (call_insn))
594 {
595 rtx link;
596
597 for (link = CALL_INSN_FUNCTION_USAGE (call_insn); XEXP (link, 1) != 0;
598 link = XEXP (link, 1))
599 ;
600
601 XEXP (link, 1) = call_fusage;
602 }
603 else
604 CALL_INSN_FUNCTION_USAGE (call_insn) = call_fusage;
605
606 /* If this is a const call, then set the insn's unchanging bit. */
607 if (ecf_flags & (ECF_CONST | ECF_PURE))
608 CONST_OR_PURE_CALL_P (call_insn) = 1;
609
610 /* If this call can't throw, attach a REG_EH_REGION reg note to that
611 effect. */
612 if (ecf_flags & ECF_NOTHROW)
613 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_EH_REGION, const0_rtx,
614 REG_NOTES (call_insn));
615
616 if (ecf_flags & ECF_NORETURN)
617 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_NORETURN, const0_rtx,
618 REG_NOTES (call_insn));
619 if (ecf_flags & ECF_ALWAYS_RETURN)
620 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_ALWAYS_RETURN, const0_rtx,
621 REG_NOTES (call_insn));
622
623 if (ecf_flags & ECF_RETURNS_TWICE)
624 {
625 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_SETJMP, const0_rtx,
626 REG_NOTES (call_insn));
627 current_function_calls_setjmp = 1;
628 }
629
630 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
631
632 /* Restore this now, so that we do defer pops for this call's args
633 if the context of the call as a whole permits. */
634 inhibit_defer_pop = old_inhibit_defer_pop;
635
636 if (n_popped > 0)
637 {
638 if (!already_popped)
639 CALL_INSN_FUNCTION_USAGE (call_insn)
640 = gen_rtx_EXPR_LIST (VOIDmode,
641 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
642 CALL_INSN_FUNCTION_USAGE (call_insn));
643 rounded_stack_size -= n_popped;
644 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
645 stack_pointer_delta -= n_popped;
646 }
647
648 if (!ACCUMULATE_OUTGOING_ARGS)
649 {
650 /* If returning from the subroutine does not automatically pop the args,
651 we need an instruction to pop them sooner or later.
652 Perhaps do it now; perhaps just record how much space to pop later.
653
654 If returning from the subroutine does pop the args, indicate that the
655 stack pointer will be changed. */
656
657 if (rounded_stack_size != 0)
658 {
659 if (ecf_flags & ECF_SP_DEPRESSED)
660 /* Just pretend we did the pop. */
661 stack_pointer_delta -= rounded_stack_size;
662 else if (flag_defer_pop && inhibit_defer_pop == 0
663 && ! (ecf_flags & (ECF_CONST | ECF_PURE)))
664 pending_stack_adjust += rounded_stack_size;
665 else
666 adjust_stack (rounded_stack_size_rtx);
667 }
668 }
669 /* When we accumulate outgoing args, we must avoid any stack manipulations.
670 Restore the stack pointer to its original value now. Usually
671 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
672 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
673 popping variants of functions exist as well.
674
675 ??? We may optimize similar to defer_pop above, but it is
676 probably not worthwhile.
677
678 ??? It will be worthwhile to enable combine_stack_adjustments even for
679 such machines. */
680 else if (n_popped)
681 anti_adjust_stack (GEN_INT (n_popped));
682}
683
684/* Determine if the function identified by NAME and FNDECL is one with
685 special properties we wish to know about.
686
687 For example, if the function might return more than one time (setjmp), then
688 set RETURNS_TWICE to a nonzero value.
689
690 Similarly set LONGJMP for if the function is in the longjmp family.
691
692 Set MALLOC for any of the standard memory allocation functions which
693 allocate from the heap.
694
695 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
696 space from the stack such as alloca. */
697
698static int
699special_function_p (fndecl, flags)
700 tree fndecl;
701 int flags;
702{
703 if (! (flags & ECF_MALLOC)
704 && fndecl && DECL_NAME (fndecl)
705 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 17
706 /* Exclude functions not at the file scope, or not `extern',
707 since they are not the magic functions we would otherwise
708 think they are. */
709 && DECL_CONTEXT (fndecl) == NULL_TREE && TREE_PUBLIC (fndecl))
710 {
711 const char *name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
712 const char *tname = name;
713
714 /* We assume that alloca will always be called by name. It
715 makes no sense to pass it as a pointer-to-function to
716 anything that does not understand its behavior. */
717 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
718 && name[0] == 'a'
719 && ! strcmp (name, "alloca"))
720 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
721 && name[0] == '_'
722 && ! strcmp (name, "__builtin_alloca"))))
723 flags |= ECF_MAY_BE_ALLOCA;
724
725 /* Disregard prefix _, __ or __x. */
726 if (name[0] == '_')
727 {
728 if (name[1] == '_' && name[2] == 'x')
729 tname += 3;
730 else if (name[1] == '_')
731 tname += 2;
732 else
733 tname += 1;
734 }
735
736 if (tname[0] == 's')
737 {
738 if ((tname[1] == 'e'
739 && (! strcmp (tname, "setjmp")
740 || ! strcmp (tname, "setjmp_syscall")))
741 || (tname[1] == 'i'
742 && ! strcmp (tname, "sigsetjmp"))
743 || (tname[1] == 'a'
744 && ! strcmp (tname, "savectx")))
745 flags |= ECF_RETURNS_TWICE;
746
747 if (tname[1] == 'i'
748 && ! strcmp (tname, "siglongjmp"))
749 flags |= ECF_LONGJMP;
750 }
751 else if ((tname[0] == 'q' && tname[1] == 's'
752 && ! strcmp (tname, "qsetjmp"))
753 || (tname[0] == 'v' && tname[1] == 'f'
754 && ! strcmp (tname, "vfork")))
755 flags |= ECF_RETURNS_TWICE;
756
757 else if (tname[0] == 'l' && tname[1] == 'o'
758 && ! strcmp (tname, "longjmp"))
759 flags |= ECF_LONGJMP;
760
761 else if ((tname[0] == 'f' && tname[1] == 'o'
762 && ! strcmp (tname, "fork"))
763 /* Linux specific: __clone. check NAME to insist on the
764 leading underscores, to avoid polluting the ISO / POSIX
765 namespace. */
766 || (name[0] == '_' && name[1] == '_'
767 && ! strcmp (tname, "clone"))
768 || (tname[0] == 'e' && tname[1] == 'x' && tname[2] == 'e'
769 && tname[3] == 'c' && (tname[4] == 'l' || tname[4] == 'v')
770 && (tname[5] == '\0'
771 || ((tname[5] == 'p' || tname[5] == 'e')
772 && tname[6] == '\0'))))
773 flags |= ECF_FORK_OR_EXEC;
774
775 /* Do not add any more malloc-like functions to this list,
776 instead mark them as malloc functions using the malloc attribute.
777 Note, realloc is not suitable for attribute malloc since
778 it may return the same address across multiple calls.
779 C++ operator new is not suitable because it is not required
780 to return a unique pointer; indeed, the standard placement new
781 just returns its argument. */
782 else if (TYPE_MODE (TREE_TYPE (TREE_TYPE (fndecl))) == Pmode
783 && (! strcmp (tname, "malloc")
784 || ! strcmp (tname, "calloc")
785 || ! strcmp (tname, "strdup")))
786 flags |= ECF_MALLOC;
787 }
788 return flags;
789}
790
791/* Return nonzero when tree represent call to longjmp. */
792
793int
794setjmp_call_p (fndecl)
795 tree fndecl;
796{
797 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
798}
799
800/* Detect flags (function attributes) from the function decl or type node. */
801
802static int
803flags_from_decl_or_type (exp)
804 tree exp;
805{
806 int flags = 0;
807 tree type = exp;
808 /* ??? We can't set IS_MALLOC for function types? */
809 if (DECL_P (exp))
810 {
811 type = TREE_TYPE (exp);
812
813 /* The function exp may have the `malloc' attribute. */
814 if (DECL_P (exp) && DECL_IS_MALLOC (exp))
815 flags |= ECF_MALLOC;
816
817 /* The function exp may have the `pure' attribute. */
818 if (DECL_P (exp) && DECL_IS_PURE (exp))
819 flags |= ECF_PURE | ECF_LIBCALL_BLOCK;
820
821 if (TREE_NOTHROW (exp))
822 flags |= ECF_NOTHROW;
823 }
824
825 if (TREE_READONLY (exp) && ! TREE_THIS_VOLATILE (exp))
826 flags |= ECF_CONST | ECF_LIBCALL_BLOCK;
827
828 if (TREE_THIS_VOLATILE (exp))
829 flags |= ECF_NORETURN;
830
831 /* Mark if the function returns with the stack pointer depressed. We
832 cannot consider it pure or constant in that case. */
833 if (TREE_CODE (type) == FUNCTION_TYPE && TYPE_RETURNS_STACK_DEPRESSED (type))
834 {
835 flags |= ECF_SP_DEPRESSED;
836 flags &= ~(ECF_PURE | ECF_CONST | ECF_LIBCALL_BLOCK);
837 }
838
839 return flags;
840}
841
842/* Precompute all register parameters as described by ARGS, storing values
843 into fields within the ARGS array.
844
845 NUM_ACTUALS indicates the total number elements in the ARGS array.
846
847 Set REG_PARM_SEEN if we encounter a register parameter. */
848
849static void
850precompute_register_parameters (num_actuals, args, reg_parm_seen)
851 int num_actuals;
852 struct arg_data *args;
853 int *reg_parm_seen;
854{
855 int i;
856
857 *reg_parm_seen = 0;
858
859 for (i = 0; i < num_actuals; i++)
860 if (args[i].reg != 0 && ! args[i].pass_on_stack)
861 {
862 *reg_parm_seen = 1;
863
864 if (args[i].value == 0)
865 {
866 push_temp_slots ();
867 args[i].value = expand_expr (args[i].tree_value, NULL_RTX,
868 VOIDmode, 0);
869 preserve_temp_slots (args[i].value);
870 pop_temp_slots ();
871
872 /* ANSI doesn't require a sequence point here,
873 but PCC has one, so this will avoid some problems. */
874 emit_queue ();
875 }
876
877 /* If we are to promote the function arg to a wider mode,
878 do it now. */
879
880 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
881 args[i].value
882 = convert_modes (args[i].mode,
883 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
884 args[i].value, args[i].unsignedp);
885
886 /* If the value is expensive, and we are inside an appropriately
887 short loop, put the value into a pseudo and then put the pseudo
888 into the hard reg.
889
890 For small register classes, also do this if this call uses
891 register parameters. This is to avoid reload conflicts while
892 loading the parameters registers. */
893
894 if ((! (GET_CODE (args[i].value) == REG
895 || (GET_CODE (args[i].value) == SUBREG
896 && GET_CODE (SUBREG_REG (args[i].value)) == REG)))
897 && args[i].mode != BLKmode
898 && rtx_cost (args[i].value, SET) > COSTS_N_INSNS (1)
899 && ((SMALL_REGISTER_CLASSES && *reg_parm_seen)
900 || preserve_subexpressions_p ()))
901 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
902 }
903}
904
905#ifdef REG_PARM_STACK_SPACE
906
907 /* The argument list is the property of the called routine and it
908 may clobber it. If the fixed area has been used for previous
909 parameters, we must save and restore it. */
910
911static rtx
912save_fixed_argument_area (reg_parm_stack_space, argblock,
913 low_to_save, high_to_save)
914 int reg_parm_stack_space;
915 rtx argblock;
916 int *low_to_save;
917 int *high_to_save;
918{
919 int i;
920 rtx save_area = NULL_RTX;
921
922 /* Compute the boundary of the that needs to be saved, if any. */
923#ifdef ARGS_GROW_DOWNWARD
924 for (i = 0; i < reg_parm_stack_space + 1; i++)
925#else
926 for (i = 0; i < reg_parm_stack_space; i++)
927#endif
928 {
929 if (i >= highest_outgoing_arg_in_use
930 || stack_usage_map[i] == 0)
931 continue;
932
933 if (*low_to_save == -1)
934 *low_to_save = i;
935
936 *high_to_save = i;
937 }
938
939 if (*low_to_save >= 0)
940 {
941 int num_to_save = *high_to_save - *low_to_save + 1;
942 enum machine_mode save_mode
943 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
944 rtx stack_area;
945
946 /* If we don't have the required alignment, must do this in BLKmode. */
947 if ((*low_to_save & (MIN (GET_MODE_SIZE (save_mode),
948 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
949 save_mode = BLKmode;
950
951#ifdef ARGS_GROW_DOWNWARD
952 stack_area
953 = gen_rtx_MEM (save_mode,
954 memory_address (save_mode,
955 plus_constant (argblock,
956 - *high_to_save)));
957#else
958 stack_area = gen_rtx_MEM (save_mode,
959 memory_address (save_mode,
960 plus_constant (argblock,
961 *low_to_save)));
962#endif
963
964 set_mem_align (stack_area, PARM_BOUNDARY);
965 if (save_mode == BLKmode)
966 {
967 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
968 /* Cannot use emit_block_move here because it can be done by a
969 library call which in turn gets into this place again and deadly
970 infinite recursion happens. */
971 move_by_pieces (validize_mem (save_area), stack_area, num_to_save,
972 PARM_BOUNDARY);
973 }
974 else
975 {
976 save_area = gen_reg_rtx (save_mode);
977 emit_move_insn (save_area, stack_area);
978 }
979 }
980
981 return save_area;
982}
983
984static void
985restore_fixed_argument_area (save_area, argblock, high_to_save, low_to_save)
986 rtx save_area;
987 rtx argblock;
988 int high_to_save;
989 int low_to_save;
990{
991 enum machine_mode save_mode = GET_MODE (save_area);
992#ifdef ARGS_GROW_DOWNWARD
993 rtx stack_area
994 = gen_rtx_MEM (save_mode,
995 memory_address (save_mode,
996 plus_constant (argblock,
997 - high_to_save)));
998#else
999 rtx stack_area
1000 = gen_rtx_MEM (save_mode,
1001 memory_address (save_mode,
1002 plus_constant (argblock,
1003 low_to_save)));
1004#endif
1005
1006 if (save_mode != BLKmode)
1007 emit_move_insn (stack_area, save_area);
1008 else
1009 /* Cannot use emit_block_move here because it can be done by a library
1010 call which in turn gets into this place again and deadly infinite
1011 recursion happens. */
1012 move_by_pieces (stack_area, validize_mem (save_area),
1013 high_to_save - low_to_save + 1, PARM_BOUNDARY);
1014}
1015#endif /* REG_PARM_STACK_SPACE */
1016
1017/* If any elements in ARGS refer to parameters that are to be passed in
1018 registers, but not in memory, and whose alignment does not permit a
1019 direct copy into registers. Copy the values into a group of pseudos
1020 which we will later copy into the appropriate hard registers.
1021
1022 Pseudos for each unaligned argument will be stored into the array
1023 args[argnum].aligned_regs. The caller is responsible for deallocating
1024 the aligned_regs array if it is nonzero. */
1025
1026static void
1027store_unaligned_arguments_into_pseudos (args, num_actuals)
1028 struct arg_data *args;
1029 int num_actuals;
1030{
1031 int i, j;
1032
1033 for (i = 0; i < num_actuals; i++)
1034 if (args[i].reg != 0 && ! args[i].pass_on_stack
1035 && args[i].mode == BLKmode
1036 && (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
1037 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1038 {
1039 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1040 int big_endian_correction = 0;
1041
1042 args[i].n_aligned_regs
1043 = args[i].partial ? args[i].partial
1044 : (bytes + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
1045
1046 args[i].aligned_regs = (rtx *) xmalloc (sizeof (rtx)
1047 * args[i].n_aligned_regs);
1048
1049 /* Structures smaller than a word are aligned to the least
1050 significant byte (to the right). On a BYTES_BIG_ENDIAN machine,
1051 this means we must skip the empty high order bytes when
1052 calculating the bit offset. */
1053 if (BYTES_BIG_ENDIAN
1054 && !FUNCTION_ARG_REG_LITTLE_ENDIAN
1055 && bytes < UNITS_PER_WORD)
1056 big_endian_correction = (BITS_PER_WORD - (bytes * BITS_PER_UNIT));
1057
1058 for (j = 0; j < args[i].n_aligned_regs; j++)
1059 {
1060 rtx reg = gen_reg_rtx (word_mode);
1061 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1062 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
1063
1064 args[i].aligned_regs[j] = reg;
1065
1066 /* There is no need to restrict this code to loading items
1067 in TYPE_ALIGN sized hunks. The bitfield instructions can
1068 load up entire word sized registers efficiently.
1069
1070 ??? This may not be needed anymore.
1071 We use to emit a clobber here but that doesn't let later
1072 passes optimize the instructions we emit. By storing 0 into
1073 the register later passes know the first AND to zero out the
1074 bitfield being set in the register is unnecessary. The store
1075 of 0 will be deleted as will at least the first AND. */
1076
1077 emit_move_insn (reg, const0_rtx);
1078
1079 bytes -= bitsize / BITS_PER_UNIT;
1080 store_bit_field (reg, bitsize, big_endian_correction, word_mode,
1081 extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
1082 word_mode, word_mode,
1083 BITS_PER_WORD),
1084 BITS_PER_WORD);
1085 }
1086 }
1087}
1088
1089/* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1090 ACTPARMS.
1091
1092 NUM_ACTUALS is the total number of parameters.
1093
1094 N_NAMED_ARGS is the total number of named arguments.
1095
1096 FNDECL is the tree code for the target of this call (if known)
1097
1098 ARGS_SO_FAR holds state needed by the target to know where to place
1099 the next argument.
1100
1101 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1102 for arguments which are passed in registers.
1103
1104 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1105 and may be modified by this routine.
1106
1107 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1108 flags which may may be modified by this routine. */
1109
1110static void
1111initialize_argument_information (num_actuals, args, args_size, n_named_args,
1112 actparms, fndecl, args_so_far,
1113 reg_parm_stack_space, old_stack_level,
1114 old_pending_adj, must_preallocate,
1115 ecf_flags)
1116 int num_actuals ATTRIBUTE_UNUSED;
1117 struct arg_data *args;
1118 struct args_size *args_size;
1119 int n_named_args ATTRIBUTE_UNUSED;
1120 tree actparms;
1121 tree fndecl;
1122 CUMULATIVE_ARGS *args_so_far;
1123 int reg_parm_stack_space;
1124 rtx *old_stack_level;
1125 int *old_pending_adj;
1126 int *must_preallocate;
1127 int *ecf_flags;
1128{
1129 /* 1 if scanning parms front to back, -1 if scanning back to front. */
1130 int inc;
1131
1132 /* Count arg position in order args appear. */
1133 int argpos;
1134
1135 struct args_size alignment_pad;
1136 int i;
1137 tree p;
1138
1139 args_size->constant = 0;
1140 args_size->var = 0;
1141
1142 /* In this loop, we consider args in the order they are written.
1143 We fill up ARGS from the front or from the back if necessary
1144 so that in any case the first arg to be pushed ends up at the front. */
1145
1146 if (PUSH_ARGS_REVERSED)
1147 {
1148 i = num_actuals - 1, inc = -1;
1149 /* In this case, must reverse order of args
1150 so that we compute and push the last arg first. */
1151 }
1152 else
1153 {
1154 i = 0, inc = 1;
1155 }
1156
1157 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1158 for (p = actparms, argpos = 0; p; p = TREE_CHAIN (p), i += inc, argpos++)
1159 {
1160 tree type = TREE_TYPE (TREE_VALUE (p));
1161 int unsignedp;
1162 enum machine_mode mode;
1163
1164 args[i].tree_value = TREE_VALUE (p);
1165
1166 /* Replace erroneous argument with constant zero. */
1167 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1168 args[i].tree_value = integer_zero_node, type = integer_type_node;
1169
1170 /* If TYPE is a transparent union, pass things the way we would
1171 pass the first field of the union. We have already verified that
1172 the modes are the same. */
1173 if (TREE_CODE (type) == UNION_TYPE && TYPE_TRANSPARENT_UNION (type))
1174 type = TREE_TYPE (TYPE_FIELDS (type));
1175
1176 /* Decide where to pass this arg.
1177
1178 args[i].reg is nonzero if all or part is passed in registers.
1179
1180 args[i].partial is nonzero if part but not all is passed in registers,
1181 and the exact value says how many words are passed in registers.
1182
1183 args[i].pass_on_stack is nonzero if the argument must at least be
1184 computed on the stack. It may then be loaded back into registers
1185 if args[i].reg is nonzero.
1186
1187 These decisions are driven by the FUNCTION_... macros and must agree
1188 with those made by function.c. */
1189
1190 /* See if this argument should be passed by invisible reference. */
1191 if ((TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1192 && contains_placeholder_p (TYPE_SIZE (type)))
1193 || TREE_ADDRESSABLE (type)
1194#ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1195 || FUNCTION_ARG_PASS_BY_REFERENCE (*args_so_far, TYPE_MODE (type),
1196 type, argpos < n_named_args)
1197#endif
1198 )
1199 {
1200 /* If we're compiling a thunk, pass through invisible
1201 references instead of making a copy. */
1202 if (current_function_is_thunk
1203#ifdef FUNCTION_ARG_CALLEE_COPIES
1204 || (FUNCTION_ARG_CALLEE_COPIES (*args_so_far, TYPE_MODE (type),
1205 type, argpos < n_named_args)
1206 /* If it's in a register, we must make a copy of it too. */
1207 /* ??? Is this a sufficient test? Is there a better one? */
1208 && !(TREE_CODE (args[i].tree_value) == VAR_DECL
1209 && REG_P (DECL_RTL (args[i].tree_value)))
1210 && ! TREE_ADDRESSABLE (type))
1211#endif
1212 )
1213 {
1214 /* C++ uses a TARGET_EXPR to indicate that we want to make a
1215 new object from the argument. If we are passing by
1216 invisible reference, the callee will do that for us, so we
1217 can strip off the TARGET_EXPR. This is not always safe,
1218 but it is safe in the only case where this is a useful
1219 optimization; namely, when the argument is a plain object.
1220 In that case, the frontend is just asking the backend to
1221 make a bitwise copy of the argument. */
1222
1223 if (TREE_CODE (args[i].tree_value) == TARGET_EXPR
1224 && (DECL_P (TREE_OPERAND (args[i].tree_value, 1)))
1225 && ! REG_P (DECL_RTL (TREE_OPERAND (args[i].tree_value, 1))))
1226 args[i].tree_value = TREE_OPERAND (args[i].tree_value, 1);
1227
1228 args[i].tree_value = build1 (ADDR_EXPR,
1229 build_pointer_type (type),
1230 args[i].tree_value);
1231 type = build_pointer_type (type);
1232 }
1233 else if (TREE_CODE (args[i].tree_value) == TARGET_EXPR)
1234 {
1235 /* In the V3 C++ ABI, parameters are destroyed in the caller.
1236 We implement this by passing the address of the temporary
1237 rather than expanding it into another allocated slot. */
1238 args[i].tree_value = build1 (ADDR_EXPR,
1239 build_pointer_type (type),
1240 args[i].tree_value);
1241 type = build_pointer_type (type);
1242 }
1243 else
1244 {
1245 /* We make a copy of the object and pass the address to the
1246 function being called. */
1247 rtx copy;
1248
1249 if (!COMPLETE_TYPE_P (type)
1250 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1251 || (flag_stack_check && ! STACK_CHECK_BUILTIN
1252 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type),
1253 STACK_CHECK_MAX_VAR_SIZE))))
1254 {
1255 /* This is a variable-sized object. Make space on the stack
1256 for it. */
1257 rtx size_rtx = expr_size (TREE_VALUE (p));
1258
1259 if (*old_stack_level == 0)
1260 {
1261 emit_stack_save (SAVE_BLOCK, old_stack_level, NULL_RTX);
1262 *old_pending_adj = pending_stack_adjust;
1263 pending_stack_adjust = 0;
1264 }
1265
1266 copy = gen_rtx_MEM (BLKmode,
1267 allocate_dynamic_stack_space
1268 (size_rtx, NULL_RTX, TYPE_ALIGN (type)));
1269 set_mem_attributes (copy, type, 1);
1270 }
1271 else
1272 copy = assign_temp (type, 0, 1, 0);
1273
1274 store_expr (args[i].tree_value, copy, 0);
1275 *ecf_flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
1276
1277 args[i].tree_value = build1 (ADDR_EXPR,
1278 build_pointer_type (type),
1279 make_tree (type, copy));
1280 type = build_pointer_type (type);
1281 }
1282 }
1283
1284 mode = TYPE_MODE (type);
1285 unsignedp = TREE_UNSIGNED (type);
1286
1287#ifdef PROMOTE_FUNCTION_ARGS
1288 mode = promote_mode (type, mode, &unsignedp, 1);
1289#endif
1290
1291 args[i].unsignedp = unsignedp;
1292 args[i].mode = mode;
1293
1294 args[i].reg = FUNCTION_ARG (*args_so_far, mode, type,
1295 argpos < n_named_args);
1296#ifdef FUNCTION_INCOMING_ARG
1297 /* If this is a sibling call and the machine has register windows, the
1298 register window has to be unwinded before calling the routine, so
1299 arguments have to go into the incoming registers. */
1300 args[i].tail_call_reg = FUNCTION_INCOMING_ARG (*args_so_far, mode, type,
1301 argpos < n_named_args);
1302#else
1303 args[i].tail_call_reg = args[i].reg;
1304#endif
1305
1306#ifdef FUNCTION_ARG_PARTIAL_NREGS
1307 if (args[i].reg)
1308 args[i].partial
1309 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far, mode, type,
1310 argpos < n_named_args);
1311#endif
1312
1313 args[i].pass_on_stack = MUST_PASS_IN_STACK (mode, type);
1314
1315 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1316 it means that we are to pass this arg in the register(s) designated
1317 by the PARALLEL, but also to pass it in the stack. */
1318 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1319 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1320 args[i].pass_on_stack = 1;
1321
1322 /* If this is an addressable type, we must preallocate the stack
1323 since we must evaluate the object into its final location.
1324
1325 If this is to be passed in both registers and the stack, it is simpler
1326 to preallocate. */
1327 if (TREE_ADDRESSABLE (type)
1328 || (args[i].pass_on_stack && args[i].reg != 0))
1329 *must_preallocate = 1;
1330
1331 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1332 we cannot consider this function call constant. */
1333 if (TREE_ADDRESSABLE (type))
1334 *ecf_flags &= ~ECF_LIBCALL_BLOCK;
1335
1336 /* Compute the stack-size of this argument. */
1337 if (args[i].reg == 0 || args[i].partial != 0
1338 || reg_parm_stack_space > 0
1339 || args[i].pass_on_stack)
1340 locate_and_pad_parm (mode, type,
1341#ifdef STACK_PARMS_IN_REG_PARM_AREA
1342 1,
1343#else
1344 args[i].reg != 0,
1345#endif
1346 fndecl, args_size, &args[i].offset,
1347 &args[i].size, &alignment_pad);
1348
1349#ifndef ARGS_GROW_DOWNWARD
1350 args[i].slot_offset = *args_size;
1351#endif
1352
1353 args[i].alignment_pad = alignment_pad;
1354
1355 /* If a part of the arg was put into registers,
1356 don't include that part in the amount pushed. */
1357 if (reg_parm_stack_space == 0 && ! args[i].pass_on_stack)
1358 args[i].size.constant -= ((args[i].partial * UNITS_PER_WORD)
1359 / (PARM_BOUNDARY / BITS_PER_UNIT)
1360 * (PARM_BOUNDARY / BITS_PER_UNIT));
1361
1362 /* Update ARGS_SIZE, the total stack space for args so far. */
1363
1364 args_size->constant += args[i].size.constant;
1365 if (args[i].size.var)
1366 {
1367 ADD_PARM_SIZE (*args_size, args[i].size.var);
1368 }
1369
1370 /* Since the slot offset points to the bottom of the slot,
1371 we must record it after incrementing if the args grow down. */
1372#ifdef ARGS_GROW_DOWNWARD
1373 args[i].slot_offset = *args_size;
1374
1375 args[i].slot_offset.constant = -args_size->constant;
1376 if (args_size->var)
1377 SUB_PARM_SIZE (args[i].slot_offset, args_size->var);
1378#endif
1379
1380 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1381 have been used, etc. */
1382
1383 FUNCTION_ARG_ADVANCE (*args_so_far, TYPE_MODE (type), type,
1384 argpos < n_named_args);
1385 }
1386}
1387
1388/* Update ARGS_SIZE to contain the total size for the argument block.
1389 Return the original constant component of the argument block's size.
1390
1391 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1392 for arguments passed in registers. */
1393
1394static int
1395compute_argument_block_size (reg_parm_stack_space, args_size,
1396 preferred_stack_boundary)
1397 int reg_parm_stack_space;
1398 struct args_size *args_size;
1399 int preferred_stack_boundary ATTRIBUTE_UNUSED;
1400{
1401 int unadjusted_args_size = args_size->constant;
1402
1403 /* For accumulate outgoing args mode we don't need to align, since the frame
1404 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1405 backends from generating misaligned frame sizes. */
1406 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1407 preferred_stack_boundary = STACK_BOUNDARY;
1408
1409 /* Compute the actual size of the argument block required. The variable
1410 and constant sizes must be combined, the size may have to be rounded,
1411 and there may be a minimum required size. */
1412
1413 if (args_size->var)
1414 {
1415 args_size->var = ARGS_SIZE_TREE (*args_size);
1416 args_size->constant = 0;
1417
1418 preferred_stack_boundary /= BITS_PER_UNIT;
1419 if (preferred_stack_boundary > 1)
1420 {
1421 /* We don't handle this case yet. To handle it correctly we have
1422 to add the delta, round and subtract the delta.
1423 Currently no machine description requires this support. */
1424 if (stack_pointer_delta & (preferred_stack_boundary - 1))
1425 abort ();
1426 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1427 }
1428
1429 if (reg_parm_stack_space > 0)
1430 {
1431 args_size->var
1432 = size_binop (MAX_EXPR, args_size->var,
1433 ssize_int (reg_parm_stack_space));
1434
1435#ifndef OUTGOING_REG_PARM_STACK_SPACE
1436 /* The area corresponding to register parameters is not to count in
1437 the size of the block we need. So make the adjustment. */
1438 args_size->var
1439 = size_binop (MINUS_EXPR, args_size->var,
1440 ssize_int (reg_parm_stack_space));
1441#endif
1442 }
1443 }
1444 else
1445 {
1446 preferred_stack_boundary /= BITS_PER_UNIT;
1447 if (preferred_stack_boundary < 1)
1448 preferred_stack_boundary = 1;
1449 args_size->constant = (((args_size->constant
1450 + stack_pointer_delta
1451 + preferred_stack_boundary - 1)
1452 / preferred_stack_boundary
1453 * preferred_stack_boundary)
1454 - stack_pointer_delta);
1455
1456 args_size->constant = MAX (args_size->constant,
1457 reg_parm_stack_space);
1458
1459#ifdef MAYBE_REG_PARM_STACK_SPACE
1460 if (reg_parm_stack_space == 0)
1461 args_size->constant = 0;
1462#endif
1463
1464#ifndef OUTGOING_REG_PARM_STACK_SPACE
1465 args_size->constant -= reg_parm_stack_space;
1466#endif
1467 }
1468 return unadjusted_args_size;
1469}
1470
1471/* Precompute parameters as needed for a function call.
1472
1473 FLAGS is mask of ECF_* constants.
1474
1475 NUM_ACTUALS is the number of arguments.
1476
1477 ARGS is an array containing information for each argument; this
1478 routine fills in the INITIAL_VALUE and VALUE fields for each
1479 precomputed argument. */
1480
1481static void
1482precompute_arguments (flags, num_actuals, args)
1483 int flags;
1484 int num_actuals;
1485 struct arg_data *args;
1486{
1487 int i;
1488
1489 /* If this function call is cse'able, precompute all the parameters.
1490 Note that if the parameter is constructed into a temporary, this will
1491 cause an additional copy because the parameter will be constructed
1492 into a temporary location and then copied into the outgoing arguments.
1493 If a parameter contains a call to alloca and this function uses the
1494 stack, precompute the parameter. */
1495
1496 /* If we preallocated the stack space, and some arguments must be passed
1497 on the stack, then we must precompute any parameter which contains a
1498 function call which will store arguments on the stack.
1499 Otherwise, evaluating the parameter may clobber previous parameters
1500 which have already been stored into the stack. (we have code to avoid
1501 such case by saving the outgoing stack arguments, but it results in
1502 worse code) */
1503
1504 for (i = 0; i < num_actuals; i++)
1505 if ((flags & ECF_LIBCALL_BLOCK)
1506 || calls_function (args[i].tree_value, !ACCUMULATE_OUTGOING_ARGS))
1507 {
1508 enum machine_mode mode;
1509
1510 /* If this is an addressable type, we cannot pre-evaluate it. */
1511 if (TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value)))
1512 abort ();
1513
1514 args[i].value
1515 = expand_expr (args[i].tree_value, NULL_RTX, VOIDmode, 0);
1516
1517 /* ANSI doesn't require a sequence point here,
1518 but PCC has one, so this will avoid some problems. */
1519 emit_queue ();
1520
1521 args[i].initial_value = args[i].value
1522 = protect_from_queue (args[i].value, 0);
1523
1524 mode = TYPE_MODE (TREE_TYPE (args[i].tree_value));
1525 if (mode != args[i].mode)
1526 {
1527 args[i].value
1528 = convert_modes (args[i].mode, mode,
1529 args[i].value, args[i].unsignedp);
1530#ifdef PROMOTE_FOR_CALL_ONLY
1531 /* CSE will replace this only if it contains args[i].value
1532 pseudo, so convert it down to the declared mode using
1533 a SUBREG. */
1534 if (GET_CODE (args[i].value) == REG
1535 && GET_MODE_CLASS (args[i].mode) == MODE_INT)
1536 {
1537 args[i].initial_value
1538 = gen_lowpart_SUBREG (mode, args[i].value);
1539 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
1540 SUBREG_PROMOTED_UNSIGNED_P (args[i].initial_value)
1541 = args[i].unsignedp;
1542 }
1543#endif
1544 }
1545 }
1546}
1547
1548/* Given the current state of MUST_PREALLOCATE and information about
1549 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1550 compute and return the final value for MUST_PREALLOCATE. */
1551
1552static int
1553finalize_must_preallocate (must_preallocate, num_actuals, args, args_size)
1554 int must_preallocate;
1555 int num_actuals;
1556 struct arg_data *args;
1557 struct args_size *args_size;
1558{
1559 /* See if we have or want to preallocate stack space.
1560
1561 If we would have to push a partially-in-regs parm
1562 before other stack parms, preallocate stack space instead.
1563
1564 If the size of some parm is not a multiple of the required stack
1565 alignment, we must preallocate.
1566
1567 If the total size of arguments that would otherwise create a copy in
1568 a temporary (such as a CALL) is more than half the total argument list
1569 size, preallocation is faster.
1570
1571 Another reason to preallocate is if we have a machine (like the m88k)
1572 where stack alignment is required to be maintained between every
1573 pair of insns, not just when the call is made. However, we assume here
1574 that such machines either do not have push insns (and hence preallocation
1575 would occur anyway) or the problem is taken care of with
1576 PUSH_ROUNDING. */
1577
1578 if (! must_preallocate)
1579 {
1580 int partial_seen = 0;
1581 int copy_to_evaluate_size = 0;
1582 int i;
1583
1584 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1585 {
1586 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1587 partial_seen = 1;
1588 else if (partial_seen && args[i].reg == 0)
1589 must_preallocate = 1;
1590
1591 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1592 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1593 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1594 || TREE_CODE (args[i].tree_value) == COND_EXPR
1595 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1596 copy_to_evaluate_size
1597 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1598 }
1599
1600 if (copy_to_evaluate_size * 2 >= args_size->constant
1601 && args_size->constant > 0)
1602 must_preallocate = 1;
1603 }
1604 return must_preallocate;
1605}
1606
1607/* If we preallocated stack space, compute the address of each argument
1608 and store it into the ARGS array.
1609
1610 We need not ensure it is a valid memory address here; it will be
1611 validized when it is used.
1612
1613 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1614
1615static void
1616compute_argument_addresses (args, argblock, num_actuals)
1617 struct arg_data *args;
1618 rtx argblock;
1619 int num_actuals;
1620{
1621 if (argblock)
1622 {
1623 rtx arg_reg = argblock;
1624 int i, arg_offset = 0;
1625
1626 if (GET_CODE (argblock) == PLUS)
1627 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1628
1629 for (i = 0; i < num_actuals; i++)
1630 {
1631 rtx offset = ARGS_SIZE_RTX (args[i].offset);
1632 rtx slot_offset = ARGS_SIZE_RTX (args[i].slot_offset);
1633 rtx addr;
1634
1635 /* Skip this parm if it will not be passed on the stack. */
1636 if (! args[i].pass_on_stack && args[i].reg != 0)
1637 continue;
1638
1639 if (GET_CODE (offset) == CONST_INT)
1640 addr = plus_constant (arg_reg, INTVAL (offset));
1641 else
1642 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1643
1644 addr = plus_constant (addr, arg_offset);
1645 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1646 set_mem_attributes (args[i].stack,
1647 TREE_TYPE (args[i].tree_value), 1);
1648
1649 if (GET_CODE (slot_offset) == CONST_INT)
1650 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1651 else
1652 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1653
1654 addr = plus_constant (addr, arg_offset);
1655 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1656 set_mem_attributes (args[i].stack_slot,
1657 TREE_TYPE (args[i].tree_value), 1);
1658
1659 /* Function incoming arguments may overlap with sibling call
1660 outgoing arguments and we cannot allow reordering of reads
1661 from function arguments with stores to outgoing arguments
1662 of sibling calls. */
1663 set_mem_alias_set (args[i].stack, 0);
1664 set_mem_alias_set (args[i].stack_slot, 0);
1665 }
1666 }
1667}
1668
1669/* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1670 in a call instruction.
1671
1672 FNDECL is the tree node for the target function. For an indirect call
1673 FNDECL will be NULL_TREE.
1674
1675 EXP is the CALL_EXPR for this call. */
1676
1677static rtx
1678rtx_for_function_call (fndecl, exp)
1679 tree fndecl;
1680 tree exp;
1681{
1682 rtx funexp;
1683
1684 /* Get the function to call, in the form of RTL. */
1685 if (fndecl)
1686 {
1687 /* If this is the first use of the function, see if we need to
1688 make an external definition for it. */
1689 if (! TREE_USED (fndecl))
1690 {
1691 assemble_external (fndecl);
1692 TREE_USED (fndecl) = 1;
1693 }
1694
1695 /* Get a SYMBOL_REF rtx for the function address. */
1696 funexp = XEXP (DECL_RTL (fndecl), 0);
1697 }
1698 else
1699 /* Generate an rtx (probably a pseudo-register) for the address. */
1700 {
1701 rtx funaddr;
1702 push_temp_slots ();
1703 funaddr = funexp
1704 = expand_expr (TREE_OPERAND (exp, 0), NULL_RTX, VOIDmode, 0);
1705 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1706 emit_queue ();
1707 }
1708 return funexp;
1709}
1710
1711/* Do the register loads required for any wholly-register parms or any
1712 parms which are passed both on the stack and in a register. Their
1713 expressions were already evaluated.
1714
1715 Mark all register-parms as living through the call, putting these USE
1716 insns in the CALL_INSN_FUNCTION_USAGE field. */
1717
1718static void
1719load_register_parameters (args, num_actuals, call_fusage, flags)
1720 struct arg_data *args;
1721 int num_actuals;
1722 rtx *call_fusage;
1723 int flags;
1724{
1725 int i, j;
1726
1727#ifdef LOAD_ARGS_REVERSED
1728 for (i = num_actuals - 1; i >= 0; i--)
1729#else
1730 for (i = 0; i < num_actuals; i++)
1731#endif
1732 {
1733 rtx reg = ((flags & ECF_SIBCALL)
1734 ? args[i].tail_call_reg : args[i].reg);
1735 int partial = args[i].partial;
1736 int nregs;
1737
1738 if (reg)
1739 {
1740 /* Set to non-negative if must move a word at a time, even if just
1741 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1742 we just use a normal move insn. This value can be zero if the
1743 argument is a zero size structure with no fields. */
1744 nregs = (partial ? partial
1745 : (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1746 ? ((int_size_in_bytes (TREE_TYPE (args[i].tree_value))
1747 + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)
1748 : -1));
1749
1750 /* Handle calls that pass values in multiple non-contiguous
1751 locations. The Irix 6 ABI has examples of this. */
1752
1753 if (GET_CODE (reg) == PARALLEL)
1754 emit_group_load (reg, args[i].value,
1755 int_size_in_bytes (TREE_TYPE (args[i].tree_value)));
1756
1757 /* If simple case, just do move. If normal partial, store_one_arg
1758 has already loaded the register for us. In all other cases,
1759 load the register(s) from memory. */
1760
1761 else if (nregs == -1)
1762 emit_move_insn (reg, args[i].value);
1763
1764 /* If we have pre-computed the values to put in the registers in
1765 the case of non-aligned structures, copy them in now. */
1766
1767 else if (args[i].n_aligned_regs != 0)
1768 for (j = 0; j < args[i].n_aligned_regs; j++)
1769 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
1770 args[i].aligned_regs[j]);
1771
1772 else if (partial == 0 || args[i].pass_on_stack)
1773 move_block_to_reg (REGNO (reg),
1774 validize_mem (args[i].value), nregs,
1775 args[i].mode);
1776
1777 /* Handle calls that pass values in multiple non-contiguous
1778 locations. The Irix 6 ABI has examples of this. */
1779 if (GET_CODE (reg) == PARALLEL)
1780 use_group_regs (call_fusage, reg);
1781 else if (nregs == -1)
1782 use_reg (call_fusage, reg);
1783 else
1784 use_regs (call_fusage, REGNO (reg), nregs == 0 ? 1 : nregs);
1785 }
1786 }
1787}
1788
1789/* Try to integrate function. See expand_inline_function for documentation
1790 about the parameters. */
1791
1792static rtx
1793try_to_integrate (fndecl, actparms, target, ignore, type, structure_value_addr)
1794 tree fndecl;
1795 tree actparms;
1796 rtx target;
1797 int ignore;
1798 tree type;
1799 rtx structure_value_addr;
1800{
1801 rtx temp;
1802 rtx before_call;
1803 int i;
1804 rtx old_stack_level = 0;
1805 int reg_parm_stack_space = 0;
1806
1807#ifdef REG_PARM_STACK_SPACE
1808#ifdef MAYBE_REG_PARM_STACK_SPACE
1809 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
1810#else
1811 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
1812#endif
1813#endif
1814
1815 before_call = get_last_insn ();
1816
1817 timevar_push (TV_INTEGRATION);
1818
1819 temp = expand_inline_function (fndecl, actparms, target,
1820 ignore, type,
1821 structure_value_addr);
1822
1823 timevar_pop (TV_INTEGRATION);
1824
1825 /* If inlining succeeded, return. */
1826 if (temp != (rtx) (size_t) - 1)
1827 {
1828 if (ACCUMULATE_OUTGOING_ARGS)
1829 {
1830 /* If the outgoing argument list must be preserved, push
1831 the stack before executing the inlined function if it
1832 makes any calls. */
1833
1834 for (i = reg_parm_stack_space - 1; i >= 0; i--)
1835 if (i < highest_outgoing_arg_in_use && stack_usage_map[i] != 0)
1836 break;
1837
1838 if (stack_arg_under_construction || i >= 0)
1839 {
1840 rtx first_insn
1841 = before_call ? NEXT_INSN (before_call) : get_insns ();
1842 rtx insn = NULL_RTX, seq;
1843
1844 /* Look for a call in the inline function code.
1845 If DECL_SAVED_INSNS (fndecl)->outgoing_args_size is
1846 nonzero then there is a call and it is not necessary
1847 to scan the insns. */
1848
1849 if (DECL_SAVED_INSNS (fndecl)->outgoing_args_size == 0)
1850 for (insn = first_insn; insn; insn = NEXT_INSN (insn))
1851 if (GET_CODE (insn) == CALL_INSN)
1852 break;
1853
1854 if (insn)
1855 {
1856 /* Reserve enough stack space so that the largest
1857 argument list of any function call in the inline
1858 function does not overlap the argument list being
1859 evaluated. This is usually an overestimate because
1860 allocate_dynamic_stack_space reserves space for an
1861 outgoing argument list in addition to the requested
1862 space, but there is no way to ask for stack space such
1863 that an argument list of a certain length can be
1864 safely constructed.
1865
1866 Add the stack space reserved for register arguments, if
1867 any, in the inline function. What is really needed is the
1868 largest value of reg_parm_stack_space in the inline
1869 function, but that is not available. Using the current
1870 value of reg_parm_stack_space is wrong, but gives
1871 correct results on all supported machines. */
1872
1873 int adjust = (DECL_SAVED_INSNS (fndecl)->outgoing_args_size
1874 + reg_parm_stack_space);
1875
1876 start_sequence ();
1877 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1878 allocate_dynamic_stack_space (GEN_INT (adjust),
1879 NULL_RTX, BITS_PER_UNIT);
1880 seq = get_insns ();
1881 end_sequence ();
1882 emit_insns_before (seq, first_insn);
1883 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
1884 }
1885 }
1886 }
1887
1888 /* If the result is equivalent to TARGET, return TARGET to simplify
1889 checks in store_expr. They can be equivalent but not equal in the
1890 case of a function that returns BLKmode. */
1891 if (temp != target && rtx_equal_p (temp, target))
1892 return target;
1893 return temp;
1894 }
1895
1896 /* If inlining failed, mark FNDECL as needing to be compiled
1897 separately after all. If function was declared inline,
1898 give a warning. */
1899 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
1900 && optimize > 0 && !TREE_ADDRESSABLE (fndecl))
1901 {
1902 warning_with_decl (fndecl, "inlining failed in call to `%s'");
1903 warning ("called from here");
1904 }
1905 mark_addressable (fndecl);
1906 return (rtx) (size_t) - 1;
1907}
1908
1909/* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1910 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1911 bytes, then we would need to push some additional bytes to pad the
1912 arguments. So, we compute an adjust to the stack pointer for an
1913 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1914 bytes. Then, when the arguments are pushed the stack will be perfectly
1915 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1916 be popped after the call. Returns the adjustment. */
1917
1918static int
1919combine_pending_stack_adjustment_and_call (unadjusted_args_size,
1920 args_size,
1921 preferred_unit_stack_boundary)
1922 int unadjusted_args_size;
1923 struct args_size *args_size;
1924 int preferred_unit_stack_boundary;
1925{
1926 /* The number of bytes to pop so that the stack will be
1927 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1928 HOST_WIDE_INT adjustment;
1929 /* The alignment of the stack after the arguments are pushed, if we
1930 just pushed the arguments without adjust the stack here. */
1931 HOST_WIDE_INT unadjusted_alignment;
1932
1933 unadjusted_alignment
1934 = ((stack_pointer_delta + unadjusted_args_size)
1935 % preferred_unit_stack_boundary);
1936
1937 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1938 as possible -- leaving just enough left to cancel out the
1939 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1940 PENDING_STACK_ADJUST is non-negative, and congruent to
1941 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1942
1943 /* Begin by trying to pop all the bytes. */
1944 unadjusted_alignment
1945 = (unadjusted_alignment
1946 - (pending_stack_adjust % preferred_unit_stack_boundary));
1947 adjustment = pending_stack_adjust;
1948 /* Push enough additional bytes that the stack will be aligned
1949 after the arguments are pushed. */
1950 if (preferred_unit_stack_boundary > 1)
1951 {
1952 if (unadjusted_alignment > 0)
1953 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
1954 else
1955 adjustment += unadjusted_alignment;
1956 }
1957
1958 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1959 bytes after the call. The right number is the entire
1960 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1961 by the arguments in the first place. */
1962 args_size->constant
1963 = pending_stack_adjust - adjustment + unadjusted_args_size;
1964
1965 return adjustment;
1966}
1967
1968/* Scan X expression if it does not dereference any argument slots
1969 we already clobbered by tail call arguments (as noted in stored_args_map
1970 bitmap).
1971 Return non-zero if X expression dereferences such argument slots,
1972 zero otherwise. */
1973
1974static int
1975check_sibcall_argument_overlap_1 (x)
1976 rtx x;
1977{
1978 RTX_CODE code;
1979 int i, j;
1980 unsigned int k;
1981 const char *fmt;
1982
1983 if (x == NULL_RTX)
1984 return 0;
1985
1986 code = GET_CODE (x);
1987
1988 if (code == MEM)
1989 {
1990 if (XEXP (x, 0) == current_function_internal_arg_pointer)
1991 i = 0;
1992 else if (GET_CODE (XEXP (x, 0)) == PLUS
1993 && XEXP (XEXP (x, 0), 0) ==
1994 current_function_internal_arg_pointer
1995 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT)
1996 i = INTVAL (XEXP (XEXP (x, 0), 1));
1997 else
1998 return 0;
1999
2000#ifdef ARGS_GROW_DOWNWARD
2001 i = -i - GET_MODE_SIZE (GET_MODE (x));
2002#endif
2003
2004 for (k = 0; k < GET_MODE_SIZE (GET_MODE (x)); k++)
2005 if (i + k < stored_args_map->n_bits
2006 && TEST_BIT (stored_args_map, i + k))
2007 return 1;
2008
2009 return 0;
2010 }
2011
2012 /* Scan all subexpressions. */
2013 fmt = GET_RTX_FORMAT (code);
2014 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
2015 {
2016 if (*fmt == 'e')
2017 {
2018 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
2019 return 1;
2020 }
2021 else if (*fmt == 'E')
2022 {
2023 for (j = 0; j < XVECLEN (x, i); j++)
2024 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
2025 return 1;
2026 }
2027 }
2028 return 0;
2029}
2030
2031/* Scan sequence after INSN if it does not dereference any argument slots
2032 we already clobbered by tail call arguments (as noted in stored_args_map
2033 bitmap). Add stack slots for ARG to stored_args_map bitmap afterwards.
2034 Return non-zero if sequence after INSN dereferences such argument slots,
2035 zero otherwise. */
2036
2037static int
2038check_sibcall_argument_overlap (insn, arg)
2039 rtx insn;
2040 struct arg_data *arg;
2041{
2042 int low, high;
2043
2044 if (insn == NULL_RTX)
2045 insn = get_insns ();
2046 else
2047 insn = NEXT_INSN (insn);
2048
2049 for (; insn; insn = NEXT_INSN (insn))
2050 if (INSN_P (insn)
2051 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
2052 break;
2053
2054#ifdef ARGS_GROW_DOWNWARD
2055 low = -arg->slot_offset.constant - arg->size.constant;
2056#else
2057 low = arg->slot_offset.constant;
2058#endif
2059
2060 for (high = low + arg->size.constant; low < high; low++)
2061 SET_BIT (stored_args_map, low);
2062 return insn != NULL_RTX;
2063}
2064
2065/* Generate all the code for a function call
2066 and return an rtx for its value.
2067 Store the value in TARGET (specified as an rtx) if convenient.
2068 If the value is stored in TARGET then TARGET is returned.
2069 If IGNORE is nonzero, then we ignore the value of the function call. */
2070
2071rtx
2072expand_call (exp, target, ignore)
2073 tree exp;
2074 rtx target;
2075 int ignore;
2076{
2077 /* Nonzero if we are currently expanding a call. */
2078 static int currently_expanding_call = 0;
2079
2080 /* List of actual parameters. */
2081 tree actparms = TREE_OPERAND (exp, 1);
2082 /* RTX for the function to be called. */
2083 rtx funexp;
2084 /* Sequence of insns to perform a tail recursive "call". */
2085 rtx tail_recursion_insns = NULL_RTX;
2086 /* Sequence of insns to perform a normal "call". */
2087 rtx normal_call_insns = NULL_RTX;
2088 /* Sequence of insns to perform a tail recursive "call". */
2089 rtx tail_call_insns = NULL_RTX;
2090 /* Data type of the function. */
2091 tree funtype;
2092 /* Declaration of the function being called,
2093 or 0 if the function is computed (not known by name). */
2094 tree fndecl = 0;
2095 rtx insn;
2096 int try_tail_call = 1;
2097 int try_tail_recursion = 1;
2098 int pass;
2099
2100 /* Register in which non-BLKmode value will be returned,
2101 or 0 if no value or if value is BLKmode. */
2102 rtx valreg;
2103 /* Address where we should return a BLKmode value;
2104 0 if value not BLKmode. */
2105 rtx structure_value_addr = 0;
2106 /* Nonzero if that address is being passed by treating it as
2107 an extra, implicit first parameter. Otherwise,
2108 it is passed by being copied directly into struct_value_rtx. */
2109 int structure_value_addr_parm = 0;
2110 /* Size of aggregate value wanted, or zero if none wanted
2111 or if we are using the non-reentrant PCC calling convention
2112 or expecting the value in registers. */
2113 HOST_WIDE_INT struct_value_size = 0;
2114 /* Nonzero if called function returns an aggregate in memory PCC style,
2115 by returning the address of where to find it. */
2116 int pcc_struct_value = 0;
2117
2118 /* Number of actual parameters in this call, including struct value addr. */
2119 int num_actuals;
2120 /* Number of named args. Args after this are anonymous ones
2121 and they must all go on the stack. */
2122 int n_named_args;
2123
2124 /* Vector of information about each argument.
2125 Arguments are numbered in the order they will be pushed,
2126 not the order they are written. */
2127 struct arg_data *args;
2128
2129 /* Total size in bytes of all the stack-parms scanned so far. */
2130 struct args_size args_size;
2131 struct args_size adjusted_args_size;
2132 /* Size of arguments before any adjustments (such as rounding). */
2133 int unadjusted_args_size;
2134 /* Data on reg parms scanned so far. */
2135 CUMULATIVE_ARGS args_so_far;
2136 /* Nonzero if a reg parm has been scanned. */
2137 int reg_parm_seen;
2138 /* Nonzero if this is an indirect function call. */
2139
2140 /* Nonzero if we must avoid push-insns in the args for this call.
2141 If stack space is allocated for register parameters, but not by the
2142 caller, then it is preallocated in the fixed part of the stack frame.
2143 So the entire argument block must then be preallocated (i.e., we
2144 ignore PUSH_ROUNDING in that case). */
2145
2146 int must_preallocate = !PUSH_ARGS;
2147
2148 /* Size of the stack reserved for parameter registers. */
2149 int reg_parm_stack_space = 0;
2150
2151 /* Address of space preallocated for stack parms
2152 (on machines that lack push insns), or 0 if space not preallocated. */
2153 rtx argblock = 0;
2154
2155 /* Mask of ECF_ flags. */
2156 int flags = 0;
2157 /* Nonzero if this is a call to an inline function. */
2158 int is_integrable = 0;
2159#ifdef REG_PARM_STACK_SPACE
2160 /* Define the boundary of the register parm stack space that needs to be
2161 save, if any. */
2162 int low_to_save = -1, high_to_save;
2163 rtx save_area = 0; /* Place that it is saved */
2164#endif
2165
2166 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
2167 char *initial_stack_usage_map = stack_usage_map;
2168 int old_stack_arg_under_construction = 0;
2169
2170 rtx old_stack_level = 0;
2171 int old_pending_adj = 0;
2172 int old_inhibit_defer_pop = inhibit_defer_pop;
2173 int old_stack_allocated;
2174 rtx call_fusage;
2175 tree p = TREE_OPERAND (exp, 0);
2176 int i;
2177 /* The alignment of the stack, in bits. */
2178 HOST_WIDE_INT preferred_stack_boundary;
2179 /* The alignment of the stack, in bytes. */
2180 HOST_WIDE_INT preferred_unit_stack_boundary;
2181
2182 /* See if this is "nothrow" function call. */
2183 if (TREE_NOTHROW (exp))
2184 flags |= ECF_NOTHROW;
2185
2186 /* See if we can find a DECL-node for the actual function.
2187 As a result, decide whether this is a call to an integrable function. */
2188
2189 fndecl = get_callee_fndecl (exp);
2190 if (fndecl)
2191 {
2192 if (!flag_no_inline
2193 && fndecl != current_function_decl
2194 && DECL_INLINE (fndecl)
2195 && DECL_SAVED_INSNS (fndecl)
2196 && DECL_SAVED_INSNS (fndecl)->inlinable)
2197 is_integrable = 1;
2198 else if (! TREE_ADDRESSABLE (fndecl))
2199 {
2200 /* In case this function later becomes inlinable,
2201 record that there was already a non-inline call to it.
2202
2203 Use abstraction instead of setting TREE_ADDRESSABLE
2204 directly. */
2205 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
2206 && optimize > 0)
2207 {
2208 warning_with_decl (fndecl, "can't inline call to `%s'");
2209 warning ("called from here");
2210 }
2211 mark_addressable (fndecl);
2212 }
2213
2214 flags |= flags_from_decl_or_type (fndecl);
2215 }
2216
2217 /* If we don't have specific function to call, see if we have a
2218 attributes set in the type. */
2219 else
2220 flags |= flags_from_decl_or_type (TREE_TYPE (TREE_TYPE (p)));
2221
2222#ifdef REG_PARM_STACK_SPACE
2223#ifdef MAYBE_REG_PARM_STACK_SPACE
2224 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
2225#else
2226 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
2227#endif
2228#endif
2229
2230#ifndef OUTGOING_REG_PARM_STACK_SPACE
2231 if (reg_parm_stack_space > 0 && PUSH_ARGS)
2232 must_preallocate = 1;
2233#endif
2234
2235 /* Warn if this value is an aggregate type,
2236 regardless of which calling convention we are using for it. */
2237 if (warn_aggregate_return && AGGREGATE_TYPE_P (TREE_TYPE (exp)))
2238 warning ("function call has aggregate value");
2239
2240 /* Set up a place to return a structure. */
2241
2242 /* Cater to broken compilers. */
2243 if (aggregate_value_p (exp))
2244 {
2245 /* This call returns a big structure. */
2246 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
2247
2248#ifdef PCC_STATIC_STRUCT_RETURN
2249 {
2250 pcc_struct_value = 1;
2251 /* Easier than making that case work right. */
2252 if (is_integrable)
2253 {
2254 /* In case this is a static function, note that it has been
2255 used. */
2256 if (! TREE_ADDRESSABLE (fndecl))
2257 mark_addressable (fndecl);
2258 is_integrable = 0;
2259 }
2260 }
2261#else /* not PCC_STATIC_STRUCT_RETURN */
2262 {
2263 struct_value_size = int_size_in_bytes (TREE_TYPE (exp));
2264
2265 if (target && GET_CODE (target) == MEM)
2266 structure_value_addr = XEXP (target, 0);
2267 else
2268 {
2269 /* For variable-sized objects, we must be called with a target
2270 specified. If we were to allocate space on the stack here,
2271 we would have no way of knowing when to free it. */
2272 rtx d = assign_temp (TREE_TYPE (exp), 1, 1, 1);
2273
2274 mark_temp_addr_taken (d);
2275 structure_value_addr = XEXP (d, 0);
2276 target = 0;
2277 }
2278 }
2279#endif /* not PCC_STATIC_STRUCT_RETURN */
2280 }
2281
2282 /* If called function is inline, try to integrate it. */
2283
2284 if (is_integrable)
2285 {
2286 rtx temp = try_to_integrate (fndecl, actparms, target,
2287 ignore, TREE_TYPE (exp),
2288 structure_value_addr);
2289 if (temp != (rtx) (size_t) - 1)
2290 return temp;
2291 }
2292
2293 /* Figure out the amount to which the stack should be aligned. */
2294 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
2295
2296 /* Operand 0 is a pointer-to-function; get the type of the function. */
2297 funtype = TREE_TYPE (TREE_OPERAND (exp, 0));
2298 if (! POINTER_TYPE_P (funtype))
2299 abort ();
2300 funtype = TREE_TYPE (funtype);
2301
2302 /* See if this is a call to a function that can return more than once
2303 or a call to longjmp or malloc. */
2304 flags |= special_function_p (fndecl, flags);
2305
2306 if (flags & ECF_MAY_BE_ALLOCA)
2307 current_function_calls_alloca = 1;
2308
2309 /* If struct_value_rtx is 0, it means pass the address
2310 as if it were an extra parameter. */
2311 if (structure_value_addr && struct_value_rtx == 0)
2312 {
2313 /* If structure_value_addr is a REG other than
2314 virtual_outgoing_args_rtx, we can use always use it. If it
2315 is not a REG, we must always copy it into a register.
2316 If it is virtual_outgoing_args_rtx, we must copy it to another
2317 register in some cases. */
2318 rtx temp = (GET_CODE (structure_value_addr) != REG
2319 || (ACCUMULATE_OUTGOING_ARGS
2320 && stack_arg_under_construction
2321 && structure_value_addr == virtual_outgoing_args_rtx)
2322 ? copy_addr_to_reg (structure_value_addr)
2323 : structure_value_addr);
2324
2325 actparms
2326 = tree_cons (error_mark_node,
2327 make_tree (build_pointer_type (TREE_TYPE (funtype)),
2328 temp),
2329 actparms);
2330 structure_value_addr_parm = 1;
2331 }
2332
2333 /* Count the arguments and set NUM_ACTUALS. */
2334 for (p = actparms, num_actuals = 0; p; p = TREE_CHAIN (p))
2335 num_actuals++;
2336
2337 /* Compute number of named args.
2338 Normally, don't include the last named arg if anonymous args follow.
2339 We do include the last named arg if STRICT_ARGUMENT_NAMING is nonzero.
2340 (If no anonymous args follow, the result of list_length is actually
2341 one too large. This is harmless.)
2342
2343 If PRETEND_OUTGOING_VARARGS_NAMED is set and STRICT_ARGUMENT_NAMING is
2344 zero, this machine will be able to place unnamed args that were
2345 passed in registers into the stack. So treat all args as named.
2346 This allows the insns emitting for a specific argument list to be
2347 independent of the function declaration.
2348
2349 If PRETEND_OUTGOING_VARARGS_NAMED is not set, we do not have any
2350 reliable way to pass unnamed args in registers, so we must force
2351 them into memory. */
2352
2353 if ((STRICT_ARGUMENT_NAMING
2354 || ! PRETEND_OUTGOING_VARARGS_NAMED)
2355 && TYPE_ARG_TYPES (funtype) != 0)
2356 n_named_args
2357 = (list_length (TYPE_ARG_TYPES (funtype))
2358 /* Don't include the last named arg. */
2359 - (STRICT_ARGUMENT_NAMING ? 0 : 1)
2360 /* Count the struct value address, if it is passed as a parm. */
2361 + structure_value_addr_parm);
2362 else
2363 /* If we know nothing, treat all args as named. */
2364 n_named_args = num_actuals;
2365
2366 /* Start updating where the next arg would go.
2367
2368 On some machines (such as the PA) indirect calls have a different
2369 calling convention than normal calls. The last argument in
2370 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2371 or not. */
2372 INIT_CUMULATIVE_ARGS (args_so_far, funtype, NULL_RTX, (fndecl == 0));
2373
2374 /* Make a vector to hold all the information about each arg. */
2375 args = (struct arg_data *) alloca (num_actuals * sizeof (struct arg_data));
2376 memset ((char *) args, 0, num_actuals * sizeof (struct arg_data));
2377
2378 /* Build up entries in the ARGS array, compute the size of the
2379 arguments into ARGS_SIZE, etc. */
2380 initialize_argument_information (num_actuals, args, &args_size,
2381 n_named_args, actparms, fndecl,
2382 &args_so_far, reg_parm_stack_space,
2383 &old_stack_level, &old_pending_adj,
2384 &must_preallocate, &flags);
2385
2386 if (args_size.var)
2387 {
2388 /* If this function requires a variable-sized argument list, don't
2389 try to make a cse'able block for this call. We may be able to
2390 do this eventually, but it is too complicated to keep track of
2391 what insns go in the cse'able block and which don't. */
2392
2393 flags &= ~ECF_LIBCALL_BLOCK;
2394 must_preallocate = 1;
2395 }
2396
2397 /* Now make final decision about preallocating stack space. */
2398 must_preallocate = finalize_must_preallocate (must_preallocate,
2399 num_actuals, args,
2400 &args_size);
2401
2402 /* If the structure value address will reference the stack pointer, we
2403 must stabilize it. We don't need to do this if we know that we are
2404 not going to adjust the stack pointer in processing this call. */
2405
2406 if (structure_value_addr
2407 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2408 || reg_mentioned_p (virtual_outgoing_args_rtx,
2409 structure_value_addr))
2410 && (args_size.var
2411 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
2412 structure_value_addr = copy_to_reg (structure_value_addr);
2413
2414 /* Tail calls can make things harder to debug, and we're traditionally
2415 pushed these optimizations into -O2. Don't try if we're already
2416 expanding a call, as that means we're an argument. Don't try if
2417 there's cleanups, as we know there's code to follow the call.
2418
2419 If rtx_equal_function_value_matters is false, that means we've
2420 finished with regular parsing. Which means that some of the
2421 machinery we use to generate tail-calls is no longer in place.
2422 This is most often true of sjlj-exceptions, which we couldn't
2423 tail-call to anyway. */
2424
2425 if (currently_expanding_call++ != 0
2426 || !flag_optimize_sibling_calls
2427 || !rtx_equal_function_value_matters
2428 || any_pending_cleanups (1)
2429 || args_size.var)
2430 try_tail_call = try_tail_recursion = 0;
2431
2432 /* Tail recursion fails, when we are not dealing with recursive calls. */
2433 if (!try_tail_recursion
2434 || TREE_CODE (TREE_OPERAND (exp, 0)) != ADDR_EXPR
2435 || TREE_OPERAND (TREE_OPERAND (exp, 0), 0) != current_function_decl)
2436 try_tail_recursion = 0;
2437
2438 /* Rest of purposes for tail call optimizations to fail. */
2439 if (
2440#ifdef HAVE_sibcall_epilogue
2441 !HAVE_sibcall_epilogue
2442#else
2443 1
2444#endif
2445 || !try_tail_call
2446 /* Doing sibling call optimization needs some work, since
2447 structure_value_addr can be allocated on the stack.
2448 It does not seem worth the effort since few optimizable
2449 sibling calls will return a structure. */
2450 || structure_value_addr != NULL_RTX
2451 /* If the register holding the address is a callee saved
2452 register, then we lose. We have no way to prevent that,
2453 so we only allow calls to named functions. */
2454 /* ??? This could be done by having the insn constraints
2455 use a register class that is all call-clobbered. Any
2456 reload insns generated to fix things up would appear
2457 before the sibcall_epilogue. */
2458 || fndecl == NULL_TREE
2459 || (flags & (ECF_RETURNS_TWICE | ECF_LONGJMP))
2460 || TREE_THIS_VOLATILE (fndecl)
2461 || !FUNCTION_OK_FOR_SIBCALL (fndecl)
2462 /* If this function requires more stack slots than the current
2463 function, we cannot change it into a sibling call. */
2464 || args_size.constant > current_function_args_size
2465 /* If the callee pops its own arguments, then it must pop exactly
2466 the same number of arguments as the current function. */
2467 || RETURN_POPS_ARGS (fndecl, funtype, args_size.constant)
2468 != RETURN_POPS_ARGS (current_function_decl,
2469 TREE_TYPE (current_function_decl),
2470 current_function_args_size))
2471 try_tail_call = 0;
2472
2473 if (try_tail_call || try_tail_recursion)
2474 {
2475 int end, inc;
2476 actparms = NULL_TREE;
2477 /* Ok, we're going to give the tail call the old college try.
2478 This means we're going to evaluate the function arguments
2479 up to three times. There are two degrees of badness we can
2480 encounter, those that can be unsaved and those that can't.
2481 (See unsafe_for_reeval commentary for details.)
2482
2483 Generate a new argument list. Pass safe arguments through
2484 unchanged. For the easy badness wrap them in UNSAVE_EXPRs.
2485 For hard badness, evaluate them now and put their resulting
2486 rtx in a temporary VAR_DECL.
2487
2488 initialize_argument_information has ordered the array for the
2489 order to be pushed, and we must remember this when reconstructing
2490 the original argument order. */
2491
2492 if (PUSH_ARGS_REVERSED)
2493 {
2494 inc = 1;
2495 i = 0;
2496 end = num_actuals;
2497 }
2498 else
2499 {
2500 inc = -1;
2501 i = num_actuals - 1;
2502 end = -1;
2503 }
2504
2505 for (; i != end; i += inc)
2506 {
2507 switch (unsafe_for_reeval (args[i].tree_value))
2508 {
2509 case 0: /* Safe. */
2510 break;
2511
2512 case 1: /* Mildly unsafe. */
2513 args[i].tree_value = unsave_expr (args[i].tree_value);
2514 break;
2515
2516 case 2: /* Wildly unsafe. */
2517 {
2518 tree var = build_decl (VAR_DECL, NULL_TREE,
2519 TREE_TYPE (args[i].tree_value));
2520 SET_DECL_RTL (var,
2521 expand_expr (args[i].tree_value, NULL_RTX,
2522 VOIDmode, EXPAND_NORMAL));
2523 args[i].tree_value = var;
2524 }
2525 break;
2526
2527 default:
2528 abort ();
2529 }
2530 /* We need to build actparms for optimize_tail_recursion. We can
2531 safely trash away TREE_PURPOSE, since it is unused by this
2532 function. */
2533 if (try_tail_recursion)
2534 actparms = tree_cons (NULL_TREE, args[i].tree_value, actparms);
2535 }
2536 /* Expanding one of those dangerous arguments could have added
2537 cleanups, but otherwise give it a whirl. */
2538 if (any_pending_cleanups (1))
2539 try_tail_call = try_tail_recursion = 0;
2540 }
2541
2542 /* Generate a tail recursion sequence when calling ourselves. */
2543
2544 if (try_tail_recursion)
2545 {
2546 /* We want to emit any pending stack adjustments before the tail
2547 recursion "call". That way we know any adjustment after the tail
2548 recursion call can be ignored if we indeed use the tail recursion
2549 call expansion. */
2550 int save_pending_stack_adjust = pending_stack_adjust;
2551 int save_stack_pointer_delta = stack_pointer_delta;
2552
2553 /* Emit any queued insns now; otherwise they would end up in
2554 only one of the alternates. */
2555 emit_queue ();
2556
2557 /* Use a new sequence to hold any RTL we generate. We do not even
2558 know if we will use this RTL yet. The final decision can not be
2559 made until after RTL generation for the entire function is
2560 complete. */
2561 start_sequence ();
2562 /* If expanding any of the arguments creates cleanups, we can't
2563 do a tailcall. So, we'll need to pop the pending cleanups
2564 list. If, however, all goes well, and there are no cleanups
2565 then the call to expand_start_target_temps will have no
2566 effect. */
2567 expand_start_target_temps ();
2568 if (optimize_tail_recursion (actparms, get_last_insn ()))
2569 {
2570 if (any_pending_cleanups (1))
2571 try_tail_call = try_tail_recursion = 0;
2572 else
2573 tail_recursion_insns = get_insns ();
2574 }
2575 expand_end_target_temps ();
2576 end_sequence ();
2577
2578 /* Restore the original pending stack adjustment for the sibling and
2579 normal call cases below. */
2580 pending_stack_adjust = save_pending_stack_adjust;
2581 stack_pointer_delta = save_stack_pointer_delta;
2582 }
2583
2584 if (profile_arc_flag && (flags & ECF_FORK_OR_EXEC))
2585 {
2586 /* A fork duplicates the profile information, and an exec discards
2587 it. We can't rely on fork/exec to be paired. So write out the
2588 profile information we have gathered so far, and clear it. */
2589 /* ??? When Linux's __clone is called with CLONE_VM set, profiling
2590 is subject to race conditions, just as with multithreaded
2591 programs. */
2592
2593 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, "__bb_fork_func"),
2594 LCT_ALWAYS_RETURN,
2595 VOIDmode, 0);
2596 }
2597
2598 /* Ensure current function's preferred stack boundary is at least
2599 what we need. We don't have to increase alignment for recursive
2600 functions. */
2601 if (cfun->preferred_stack_boundary < preferred_stack_boundary
2602 && fndecl != current_function_decl)
2603 cfun->preferred_stack_boundary = preferred_stack_boundary;
2604
2605 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
2606
2607 function_call_count++;
2608
2609 /* We want to make two insn chains; one for a sibling call, the other
2610 for a normal call. We will select one of the two chains after
2611 initial RTL generation is complete. */
2612 for (pass = 0; pass < 2; pass++)
2613 {
2614 int sibcall_failure = 0;
2615 /* We want to emit any pending stack adjustments before the tail
2616 recursion "call". That way we know any adjustment after the tail
2617 recursion call can be ignored if we indeed use the tail recursion
2618 call expansion. */
2619 int save_pending_stack_adjust = 0;
2620 int save_stack_pointer_delta = 0;
2621 rtx insns;
2622 rtx before_call, next_arg_reg;
2623
2624 if (pass == 0)
2625 {
2626 if (! try_tail_call)
2627 continue;
2628
2629 /* Emit any queued insns now; otherwise they would end up in
2630 only one of the alternates. */
2631 emit_queue ();
2632
2633 /* State variables we need to save and restore between
2634 iterations. */
2635 save_pending_stack_adjust = pending_stack_adjust;
2636 save_stack_pointer_delta = stack_pointer_delta;
2637 }
2638 if (pass)
2639 flags &= ~ECF_SIBCALL;
2640 else
2641 flags |= ECF_SIBCALL;
2642
2643 /* Other state variables that we must reinitialize each time
2644 through the loop (that are not initialized by the loop itself). */
2645 argblock = 0;
2646 call_fusage = 0;
2647
2648 /* Start a new sequence for the normal call case.
2649
2650 From this point on, if the sibling call fails, we want to set
2651 sibcall_failure instead of continuing the loop. */
2652 start_sequence ();
2653
2654 if (pass == 0)
2655 {
2656 /* We know at this point that there are not currently any
2657 pending cleanups. If, however, in the process of evaluating
2658 the arguments we were to create some, we'll need to be
2659 able to get rid of them. */
2660 expand_start_target_temps ();
2661 }
2662
2663 /* Don't let pending stack adjusts add up to too much.
2664 Also, do all pending adjustments now if there is any chance
2665 this might be a call to alloca or if we are expanding a sibling
2666 call sequence or if we are calling a function that is to return
2667 with stack pointer depressed. */
2668 if (pending_stack_adjust >= 32
2669 || (pending_stack_adjust > 0
2670 && (flags & (ECF_MAY_BE_ALLOCA | ECF_SP_DEPRESSED)))
2671 || pass == 0)
2672 do_pending_stack_adjust ();
2673
2674 /* When calling a const function, we must pop the stack args right away,
2675 so that the pop is deleted or moved with the call. */
2676 if (pass && (flags & ECF_LIBCALL_BLOCK))
2677 NO_DEFER_POP;
2678
2679#ifdef FINAL_REG_PARM_STACK_SPACE
2680 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
2681 args_size.var);
2682#endif
2683 /* Precompute any arguments as needed. */
2684 if (pass)
2685 precompute_arguments (flags, num_actuals, args);
2686
2687 /* Now we are about to start emitting insns that can be deleted
2688 if a libcall is deleted. */
2689 if (pass && (flags & (ECF_LIBCALL_BLOCK | ECF_MALLOC)))
2690 start_sequence ();
2691
2692 adjusted_args_size = args_size;
2693 /* Compute the actual size of the argument block required. The variable
2694 and constant sizes must be combined, the size may have to be rounded,
2695 and there may be a minimum required size. When generating a sibcall
2696 pattern, do not round up, since we'll be re-using whatever space our
2697 caller provided. */
2698 unadjusted_args_size
2699 = compute_argument_block_size (reg_parm_stack_space,
2700 &adjusted_args_size,
2701 (pass == 0 ? 0
2702 : preferred_stack_boundary));
2703
2704 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
2705
2706 /* The argument block when performing a sibling call is the
2707 incoming argument block. */
2708 if (pass == 0)
2709 {
2710 argblock = virtual_incoming_args_rtx;
2711 stored_args_map = sbitmap_alloc (args_size.constant);
2712 sbitmap_zero (stored_args_map);
2713 }
2714
2715 /* If we have no actual push instructions, or shouldn't use them,
2716 make space for all args right now. */
2717 else if (adjusted_args_size.var != 0)
2718 {
2719 if (old_stack_level == 0)
2720 {
2721 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
2722 old_pending_adj = pending_stack_adjust;
2723 pending_stack_adjust = 0;
2724 /* stack_arg_under_construction says whether a stack arg is
2725 being constructed at the old stack level. Pushing the stack
2726 gets a clean outgoing argument block. */
2727 old_stack_arg_under_construction = stack_arg_under_construction;
2728 stack_arg_under_construction = 0;
2729 }
2730 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
2731 }
2732 else
2733 {
2734 /* Note that we must go through the motions of allocating an argument
2735 block even if the size is zero because we may be storing args
2736 in the area reserved for register arguments, which may be part of
2737 the stack frame. */
2738
2739 int needed = adjusted_args_size.constant;
2740
2741 /* Store the maximum argument space used. It will be pushed by
2742 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2743 checking). */
2744
2745 if (needed > current_function_outgoing_args_size)
2746 current_function_outgoing_args_size = needed;
2747
2748 if (must_preallocate)
2749 {
2750 if (ACCUMULATE_OUTGOING_ARGS)
2751 {
2752 /* Since the stack pointer will never be pushed, it is
2753 possible for the evaluation of a parm to clobber
2754 something we have already written to the stack.
2755 Since most function calls on RISC machines do not use
2756 the stack, this is uncommon, but must work correctly.
2757
2758 Therefore, we save any area of the stack that was already
2759 written and that we are using. Here we set up to do this
2760 by making a new stack usage map from the old one. The
2761 actual save will be done by store_one_arg.
2762
2763 Another approach might be to try to reorder the argument
2764 evaluations to avoid this conflicting stack usage. */
2765
2766#ifndef OUTGOING_REG_PARM_STACK_SPACE
2767 /* Since we will be writing into the entire argument area,
2768 the map must be allocated for its entire size, not just
2769 the part that is the responsibility of the caller. */
2770 needed += reg_parm_stack_space;
2771#endif
2772
2773#ifdef ARGS_GROW_DOWNWARD
2774 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2775 needed + 1);
2776#else
2777 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2778 needed);
2779#endif
2780 stack_usage_map
2781 = (char *) alloca (highest_outgoing_arg_in_use);
2782
2783 if (initial_highest_arg_in_use)
2784 memcpy (stack_usage_map, initial_stack_usage_map,
2785 initial_highest_arg_in_use);
2786
2787 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2788 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
2789 (highest_outgoing_arg_in_use
2790 - initial_highest_arg_in_use));
2791 needed = 0;
2792
2793 /* The address of the outgoing argument list must not be
2794 copied to a register here, because argblock would be left
2795 pointing to the wrong place after the call to
2796 allocate_dynamic_stack_space below. */
2797
2798 argblock = virtual_outgoing_args_rtx;
2799 }
2800 else
2801 {
2802 if (inhibit_defer_pop == 0)
2803 {
2804 /* Try to reuse some or all of the pending_stack_adjust
2805 to get this space. */
2806 needed
2807 = (combine_pending_stack_adjustment_and_call
2808 (unadjusted_args_size,
2809 &adjusted_args_size,
2810 preferred_unit_stack_boundary));
2811
2812 /* combine_pending_stack_adjustment_and_call computes
2813 an adjustment before the arguments are allocated.
2814 Account for them and see whether or not the stack
2815 needs to go up or down. */
2816 needed = unadjusted_args_size - needed;
2817
2818 if (needed < 0)
2819 {
2820 /* We're releasing stack space. */
2821 /* ??? We can avoid any adjustment at all if we're
2822 already aligned. FIXME. */
2823 pending_stack_adjust = -needed;
2824 do_pending_stack_adjust ();
2825 needed = 0;
2826 }
2827 else
2828 /* We need to allocate space. We'll do that in
2829 push_block below. */
2830 pending_stack_adjust = 0;
2831 }
2832
2833 /* Special case this because overhead of `push_block' in
2834 this case is non-trivial. */
2835 if (needed == 0)
2836 argblock = virtual_outgoing_args_rtx;
2837 else
2838 argblock = push_block (GEN_INT (needed), 0, 0);
2839
2840 /* We only really need to call `copy_to_reg' in the case
2841 where push insns are going to be used to pass ARGBLOCK
2842 to a function call in ARGS. In that case, the stack
2843 pointer changes value from the allocation point to the
2844 call point, and hence the value of
2845 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2846 as well always do it. */
2847 argblock = copy_to_reg (argblock);
2848
2849 /* The save/restore code in store_one_arg handles all
2850 cases except one: a constructor call (including a C
2851 function returning a BLKmode struct) to initialize
2852 an argument. */
2853 if (stack_arg_under_construction)
2854 {
2855#ifndef OUTGOING_REG_PARM_STACK_SPACE
2856 rtx push_size = GEN_INT (reg_parm_stack_space
2857 + adjusted_args_size.constant);
2858#else
2859 rtx push_size = GEN_INT (adjusted_args_size.constant);
2860#endif
2861 if (old_stack_level == 0)
2862 {
2863 emit_stack_save (SAVE_BLOCK, &old_stack_level,
2864 NULL_RTX);
2865 old_pending_adj = pending_stack_adjust;
2866 pending_stack_adjust = 0;
2867 /* stack_arg_under_construction says whether a stack
2868 arg is being constructed at the old stack level.
2869 Pushing the stack gets a clean outgoing argument
2870 block. */
2871 old_stack_arg_under_construction
2872 = stack_arg_under_construction;
2873 stack_arg_under_construction = 0;
2874 /* Make a new map for the new argument list. */
2875 stack_usage_map = (char *)
2876 alloca (highest_outgoing_arg_in_use);
2877 memset (stack_usage_map, 0, highest_outgoing_arg_in_use);
2878 highest_outgoing_arg_in_use = 0;
2879 }
2880 allocate_dynamic_stack_space (push_size, NULL_RTX,
2881 BITS_PER_UNIT);
2882 }
2883 /* If argument evaluation might modify the stack pointer,
2884 copy the address of the argument list to a register. */
2885 for (i = 0; i < num_actuals; i++)
2886 if (args[i].pass_on_stack)
2887 {
2888 argblock = copy_addr_to_reg (argblock);
2889 break;
2890 }
2891 }
2892 }
2893 }
2894
2895 compute_argument_addresses (args, argblock, num_actuals);
2896
2897 /* If we push args individually in reverse order, perform stack alignment
2898 before the first push (the last arg). */
2899 if (PUSH_ARGS_REVERSED && argblock == 0
2900 && adjusted_args_size.constant != unadjusted_args_size)
2901 {
2902 /* When the stack adjustment is pending, we get better code
2903 by combining the adjustments. */
2904 if (pending_stack_adjust
2905 && ! (flags & ECF_LIBCALL_BLOCK)
2906 && ! inhibit_defer_pop)
2907 {
2908 pending_stack_adjust
2909 = (combine_pending_stack_adjustment_and_call
2910 (unadjusted_args_size,
2911 &adjusted_args_size,
2912 preferred_unit_stack_boundary));
2913 do_pending_stack_adjust ();
2914 }
2915 else if (argblock == 0)
2916 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2917 - unadjusted_args_size));
2918 }
2919 /* Now that the stack is properly aligned, pops can't safely
2920 be deferred during the evaluation of the arguments. */
2921 NO_DEFER_POP;
2922
2923 funexp = rtx_for_function_call (fndecl, exp);
2924
2925 /* Figure out the register where the value, if any, will come back. */
2926 valreg = 0;
2927 if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
2928 && ! structure_value_addr)
2929 {
2930 if (pcc_struct_value)
2931 valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
2932 fndecl, (pass == 0));
2933 else
2934 valreg = hard_function_value (TREE_TYPE (exp), fndecl, (pass == 0));
2935 }
2936
2937 /* Precompute all register parameters. It isn't safe to compute anything
2938 once we have started filling any specific hard regs. */
2939 precompute_register_parameters (num_actuals, args, &reg_parm_seen);
2940
2941#ifdef REG_PARM_STACK_SPACE
2942 /* Save the fixed argument area if it's part of the caller's frame and
2943 is clobbered by argument setup for this call. */
2944 if (ACCUMULATE_OUTGOING_ARGS && pass)
2945 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
2946 &low_to_save, &high_to_save);
2947#endif
2948
2949 /* Now store (and compute if necessary) all non-register parms.
2950 These come before register parms, since they can require block-moves,
2951 which could clobber the registers used for register parms.
2952 Parms which have partial registers are not stored here,
2953 but we do preallocate space here if they want that. */
2954
2955 for (i = 0; i < num_actuals; i++)
2956 if (args[i].reg == 0 || args[i].pass_on_stack)
2957 {
2958 rtx before_arg = get_last_insn ();
2959
2960 if (store_one_arg (&args[i], argblock, flags,
2961 adjusted_args_size.var != 0,
2962 reg_parm_stack_space)
2963 || (pass == 0
2964 && check_sibcall_argument_overlap (before_arg,
2965 &args[i])))
2966 sibcall_failure = 1;
2967 }
2968
2969 /* If we have a parm that is passed in registers but not in memory
2970 and whose alignment does not permit a direct copy into registers,
2971 make a group of pseudos that correspond to each register that we
2972 will later fill. */
2973 if (STRICT_ALIGNMENT)
2974 store_unaligned_arguments_into_pseudos (args, num_actuals);
2975
2976 /* Now store any partially-in-registers parm.
2977 This is the last place a block-move can happen. */
2978 if (reg_parm_seen)
2979 for (i = 0; i < num_actuals; i++)
2980 if (args[i].partial != 0 && ! args[i].pass_on_stack)
2981 {
2982 rtx before_arg = get_last_insn ();
2983
2984 if (store_one_arg (&args[i], argblock, flags,
2985 adjusted_args_size.var != 0,
2986 reg_parm_stack_space)
2987 || (pass == 0
2988 && check_sibcall_argument_overlap (before_arg,
2989 &args[i])))
2990 sibcall_failure = 1;
2991 }
2992
2993 /* If we pushed args in forward order, perform stack alignment
2994 after pushing the last arg. */
2995 if (!PUSH_ARGS_REVERSED && argblock == 0)
2996 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2997 - unadjusted_args_size));
2998
2999 /* If register arguments require space on the stack and stack space
3000 was not preallocated, allocate stack space here for arguments
3001 passed in registers. */
3002#ifdef OUTGOING_REG_PARM_STACK_SPACE
3003 if (!ACCUMULATE_OUTGOING_ARGS
3004 && must_preallocate == 0 && reg_parm_stack_space > 0)
3005 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
3006#endif
3007
3008 /* Pass the function the address in which to return a
3009 structure value. */
3010 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
3011 {
3012 emit_move_insn (struct_value_rtx,
3013 force_reg (Pmode,
3014 force_operand (structure_value_addr,
3015 NULL_RTX)));
3016
3017 if (GET_CODE (struct_value_rtx) == REG)
3018 use_reg (&call_fusage, struct_value_rtx);
3019 }
3020
3021 funexp = prepare_call_address (funexp, fndecl, &call_fusage,
3022 reg_parm_seen, pass == 0);
3023
3024 load_register_parameters (args, num_actuals, &call_fusage, flags);
3025
3026 /* Perform postincrements before actually calling the function. */
3027 emit_queue ();
3028
3029 /* Save a pointer to the last insn before the call, so that we can
3030 later safely search backwards to find the CALL_INSN. */
3031 before_call = get_last_insn ();
3032
3033 /* Set up next argument register. For sibling calls on machines
3034 with register windows this should be the incoming register. */
3035#ifdef FUNCTION_INCOMING_ARG
3036 if (pass == 0)
3037 next_arg_reg = FUNCTION_INCOMING_ARG (args_so_far, VOIDmode,
3038 void_type_node, 1);
3039 else
3040#endif
3041 next_arg_reg = FUNCTION_ARG (args_so_far, VOIDmode,
3042 void_type_node, 1);
3043
3044 /* All arguments and registers used for the call must be set up by
3045 now! */
3046
3047 /* Stack must be properly aligned now. */
3048 if (pass && stack_pointer_delta % preferred_unit_stack_boundary)
3049 abort ();
3050
3051 /* Generate the actual call instruction. */
3052 emit_call_1 (funexp, fndecl, funtype, unadjusted_args_size,
3053 adjusted_args_size.constant, struct_value_size,
3054 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
3055 flags, & args_so_far);
3056
3057 /* Verify that we've deallocated all the stack we used. */
3058 if (pass
3059 && old_stack_allocated != stack_pointer_delta - pending_stack_adjust)
3060 abort ();
3061
3062 /* If call is cse'able, make appropriate pair of reg-notes around it.
3063 Test valreg so we don't crash; may safely ignore `const'
3064 if return type is void. Disable for PARALLEL return values, because
3065 we have no way to move such values into a pseudo register. */
3066 if (pass && (flags & ECF_LIBCALL_BLOCK))
3067 {
3068 rtx insns;
3069
3070 if (valreg == 0 || GET_CODE (valreg) == PARALLEL)
3071 {
3072 insns = get_insns ();
3073 end_sequence ();
3074 emit_insns (insns);
3075 }
3076 else
3077 {
3078 rtx note = 0;
3079 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3080
3081 /* Mark the return value as a pointer if needed. */
3082 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3083 mark_reg_pointer (temp,
3084 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp))));
3085
3086 /* Construct an "equal form" for the value which mentions all the
3087 arguments in order as well as the function name. */
3088 for (i = 0; i < num_actuals; i++)
3089 note = gen_rtx_EXPR_LIST (VOIDmode,
3090 args[i].initial_value, note);
3091 note = gen_rtx_EXPR_LIST (VOIDmode, funexp, note);
3092
3093 insns = get_insns ();
3094 end_sequence ();
3095
3096 if (flags & ECF_PURE)
3097 note = gen_rtx_EXPR_LIST (VOIDmode,
3098 gen_rtx_USE (VOIDmode,
3099 gen_rtx_MEM (BLKmode,
3100 gen_rtx_SCRATCH (VOIDmode))),
3101 note);
3102
3103 emit_libcall_block (insns, temp, valreg, note);
3104
3105 valreg = temp;
3106 }
3107 }
3108 else if (pass && (flags & ECF_MALLOC))
3109 {
3110 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3111 rtx last, insns;
3112
3113 /* The return value from a malloc-like function is a pointer. */
3114 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3115 mark_reg_pointer (temp, BIGGEST_ALIGNMENT);
3116
3117 emit_move_insn (temp, valreg);
3118
3119 /* The return value from a malloc-like function can not alias
3120 anything else. */
3121 last = get_last_insn ();
3122 REG_NOTES (last) =
3123 gen_rtx_EXPR_LIST (REG_NOALIAS, temp, REG_NOTES (last));
3124
3125 /* Write out the sequence. */
3126 insns = get_insns ();
3127 end_sequence ();
3128 emit_insns (insns);
3129 valreg = temp;
3130 }
3131
3132 /* For calls to `setjmp', etc., inform flow.c it should complain
3133 if nonvolatile values are live. For functions that cannot return,
3134 inform flow that control does not fall through. */
3135
3136 if ((flags & (ECF_NORETURN | ECF_LONGJMP)) || pass == 0)
3137 {
3138 /* The barrier must be emitted
3139 immediately after the CALL_INSN. Some ports emit more
3140 than just a CALL_INSN above, so we must search for it here. */
3141
3142 rtx last = get_last_insn ();
3143 while (GET_CODE (last) != CALL_INSN)
3144 {
3145 last = PREV_INSN (last);
3146 /* There was no CALL_INSN? */
3147 if (last == before_call)
3148 abort ();
3149 }
3150
3151 emit_barrier_after (last);
3152 }
3153
3154 if (flags & ECF_LONGJMP)
3155 current_function_calls_longjmp = 1;
3156
3157 /* If this function is returning into a memory location marked as
3158 readonly, it means it is initializing that location. But we normally
3159 treat functions as not clobbering such locations, so we need to
3160 specify that this one does. */
3161 if (target != 0 && GET_CODE (target) == MEM
3162 && structure_value_addr != 0 && RTX_UNCHANGING_P (target))
3163 emit_insn (gen_rtx_CLOBBER (VOIDmode, target));
3164
3165 /* If value type not void, return an rtx for the value. */
3166
3167 /* If there are cleanups to be called, don't use a hard reg as target.
3168 We need to double check this and see if it matters anymore. */
3169 if (any_pending_cleanups (1))
3170 {
3171 if (target && REG_P (target)
3172 && REGNO (target) < FIRST_PSEUDO_REGISTER)
3173 target = 0;
3174 sibcall_failure = 1;
3175 }
3176
3177 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
3178 || ignore)
3179 target = const0_rtx;
3180 else if (structure_value_addr)
3181 {
3182 if (target == 0 || GET_CODE (target) != MEM)
3183 {
3184 target
3185 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3186 memory_address (TYPE_MODE (TREE_TYPE (exp)),
3187 structure_value_addr));
3188 set_mem_attributes (target, exp, 1);
3189 }
3190 }
3191 else if (pcc_struct_value)
3192 {
3193 /* This is the special C++ case where we need to
3194 know what the true target was. We take care to
3195 never use this value more than once in one expression. */
3196 target = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3197 copy_to_reg (valreg));
3198 set_mem_attributes (target, exp, 1);
3199 }
3200 /* Handle calls that return values in multiple non-contiguous locations.
3201 The Irix 6 ABI has examples of this. */
3202 else if (GET_CODE (valreg) == PARALLEL)
3203 {
3204 if (target == 0)
3205 {
3206 /* This will only be assigned once, so it can be readonly. */
3207 tree nt = build_qualified_type (TREE_TYPE (exp),
3208 (TYPE_QUALS (TREE_TYPE (exp))
3209 | TYPE_QUAL_CONST));
3210
3211 target = assign_temp (nt, 0, 1, 1);
3212 preserve_temp_slots (target);
3213 }
3214
3215 if (! rtx_equal_p (target, valreg))
3216 emit_group_store (target, valreg,
3217 int_size_in_bytes (TREE_TYPE (exp)));
3218
3219 /* We can not support sibling calls for this case. */
3220 sibcall_failure = 1;
3221 }
3222 else if (target
3223 && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
3224 && GET_MODE (target) == GET_MODE (valreg))
3225 {
3226 /* TARGET and VALREG cannot be equal at this point because the
3227 latter would not have REG_FUNCTION_VALUE_P true, while the
3228 former would if it were referring to the same register.
3229
3230 If they refer to the same register, this move will be a no-op,
3231 except when function inlining is being done. */
3232 emit_move_insn (target, valreg);
3233 }
3234 else if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
3235 {
3236 target = copy_blkmode_from_reg (target, valreg, TREE_TYPE (exp));
3237
3238 /* We can not support sibling calls for this case. */
3239 sibcall_failure = 1;
3240 }
3241 else
3242 target = copy_to_reg (valreg);
3243
3244#ifdef PROMOTE_FUNCTION_RETURN
3245 /* If we promoted this return value, make the proper SUBREG. TARGET
3246 might be const0_rtx here, so be careful. */
3247 if (GET_CODE (target) == REG
3248 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
3249 && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
3250 {
3251 tree type = TREE_TYPE (exp);
3252 int unsignedp = TREE_UNSIGNED (type);
3253 int offset = 0;
3254
3255 /* If we don't promote as expected, something is wrong. */
3256 if (GET_MODE (target)
3257 != promote_mode (type, TYPE_MODE (type), &unsignedp, 1))
3258 abort ();
3259
3260 if ((WORDS_BIG_ENDIAN || BYTES_BIG_ENDIAN)
3261 && GET_MODE_SIZE (GET_MODE (target))
3262 > GET_MODE_SIZE (TYPE_MODE (type)))
3263 {
3264 offset = GET_MODE_SIZE (GET_MODE (target))
3265 - GET_MODE_SIZE (TYPE_MODE (type));
3266 if (! BYTES_BIG_ENDIAN)
3267 offset = (offset / UNITS_PER_WORD) * UNITS_PER_WORD;
3268 else if (! WORDS_BIG_ENDIAN)
3269 offset %= UNITS_PER_WORD;
3270 }
3271 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
3272 SUBREG_PROMOTED_VAR_P (target) = 1;
3273 SUBREG_PROMOTED_UNSIGNED_P (target) = unsignedp;
3274 }
3275#endif
3276
3277 /* If size of args is variable or this was a constructor call for a stack
3278 argument, restore saved stack-pointer value. */
3279
3280 if (old_stack_level && ! (flags & ECF_SP_DEPRESSED))
3281 {
3282 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
3283 pending_stack_adjust = old_pending_adj;
3284 stack_arg_under_construction = old_stack_arg_under_construction;
3285 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3286 stack_usage_map = initial_stack_usage_map;
3287 sibcall_failure = 1;
3288 }
3289 else if (ACCUMULATE_OUTGOING_ARGS && pass)
3290 {
3291#ifdef REG_PARM_STACK_SPACE
3292 if (save_area)
3293 {
3294 restore_fixed_argument_area (save_area, argblock,
3295 high_to_save, low_to_save);
3296 }
3297#endif
3298
3299 /* If we saved any argument areas, restore them. */
3300 for (i = 0; i < num_actuals; i++)
3301 if (args[i].save_area)
3302 {
3303 enum machine_mode save_mode = GET_MODE (args[i].save_area);
3304 rtx stack_area
3305 = gen_rtx_MEM (save_mode,
3306 memory_address (save_mode,
3307 XEXP (args[i].stack_slot, 0)));
3308
3309 if (save_mode != BLKmode)
3310 emit_move_insn (stack_area, args[i].save_area);
3311 else
3312 emit_block_move (stack_area,
3313 validize_mem (args[i].save_area),
3314 GEN_INT (args[i].size.constant));
3315 }
3316
3317 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3318 stack_usage_map = initial_stack_usage_map;
3319 }
3320
3321 /* If this was alloca, record the new stack level for nonlocal gotos.
3322 Check for the handler slots since we might not have a save area
3323 for non-local gotos. */
3324
3325 if ((flags & ECF_MAY_BE_ALLOCA) && nonlocal_goto_handler_slots != 0)
3326 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
3327
3328 /* Free up storage we no longer need. */
3329 for (i = 0; i < num_actuals; ++i)
3330 if (args[i].aligned_regs)
3331 free (args[i].aligned_regs);
3332
3333 if (pass == 0)
3334 {
3335 /* Undo the fake expand_start_target_temps we did earlier. If
3336 there had been any cleanups created, we've already set
3337 sibcall_failure. */
3338 expand_end_target_temps ();
3339 }
3340
3341 insns = get_insns ();
3342 end_sequence ();
3343
3344 if (pass == 0)
3345 {
3346 tail_call_insns = insns;
3347
3348 /* Restore the pending stack adjustment now that we have
3349 finished generating the sibling call sequence. */
3350
3351 pending_stack_adjust = save_pending_stack_adjust;
3352 stack_pointer_delta = save_stack_pointer_delta;
3353
3354 /* Prepare arg structure for next iteration. */
3355 for (i = 0; i < num_actuals; i++)
3356 {
3357 args[i].value = 0;
3358 args[i].aligned_regs = 0;
3359 args[i].stack = 0;
3360 }
3361
3362 sbitmap_free (stored_args_map);
3363 }
3364 else
3365 normal_call_insns = insns;
3366
3367 /* If something prevents making this a sibling call,
3368 zero out the sequence. */
3369 if (sibcall_failure)
3370 tail_call_insns = NULL_RTX;
3371 }
3372
3373 /* The function optimize_sibling_and_tail_recursive_calls doesn't
3374 handle CALL_PLACEHOLDERs inside other CALL_PLACEHOLDERs. This
3375 can happen if the arguments to this function call an inline
3376 function who's expansion contains another CALL_PLACEHOLDER.
3377
3378 If there are any C_Ps in any of these sequences, replace them
3379 with their normal call. */
3380
3381 for (insn = normal_call_insns; insn; insn = NEXT_INSN (insn))
3382 if (GET_CODE (insn) == CALL_INSN
3383 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3384 replace_call_placeholder (insn, sibcall_use_normal);
3385
3386 for (insn = tail_call_insns; insn; insn = NEXT_INSN (insn))
3387 if (GET_CODE (insn) == CALL_INSN
3388 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3389 replace_call_placeholder (insn, sibcall_use_normal);
3390
3391 for (insn = tail_recursion_insns; insn; insn = NEXT_INSN (insn))
3392 if (GET_CODE (insn) == CALL_INSN
3393 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3394 replace_call_placeholder (insn, sibcall_use_normal);
3395
3396 /* If this was a potential tail recursion site, then emit a
3397 CALL_PLACEHOLDER with the normal and the tail recursion streams.
3398 One of them will be selected later. */
3399 if (tail_recursion_insns || tail_call_insns)
3400 {
3401 /* The tail recursion label must be kept around. We could expose
3402 its use in the CALL_PLACEHOLDER, but that creates unwanted edges
3403 and makes determining true tail recursion sites difficult.
3404
3405 So we set LABEL_PRESERVE_P here, then clear it when we select
3406 one of the call sequences after rtl generation is complete. */
3407 if (tail_recursion_insns)
3408 LABEL_PRESERVE_P (tail_recursion_label) = 1;
3409 emit_call_insn (gen_rtx_CALL_PLACEHOLDER (VOIDmode, normal_call_insns,
3410 tail_call_insns,
3411 tail_recursion_insns,
3412 tail_recursion_label));
3413 }
3414 else
3415 emit_insns (normal_call_insns);
3416
3417 currently_expanding_call--;
3418
3419 /* If this function returns with the stack pointer depressed, ensure
3420 this block saves and restores the stack pointer, show it was
3421 changed, and adjust for any outgoing arg space. */
3422 if (flags & ECF_SP_DEPRESSED)
3423 {
3424 clear_pending_stack_adjust ();
3425 emit_insn (gen_rtx (CLOBBER, VOIDmode, stack_pointer_rtx));
3426 emit_move_insn (virtual_stack_dynamic_rtx, stack_pointer_rtx);
3427 save_stack_pointer ();
3428 }
3429
3430 return target;
3431}
3432
3433/* Output a library call to function FUN (a SYMBOL_REF rtx).
3434 The RETVAL parameter specifies whether return value needs to be saved, other
3435 parameters are documented in the emit_library_call function below. */
3436
3437static rtx
3438emit_library_call_value_1 (retval, orgfun, value, fn_type, outmode, nargs, p)
3439 int retval;
3440 rtx orgfun;
3441 rtx value;
3442 enum libcall_type fn_type;
3443 enum machine_mode outmode;
3444 int nargs;
3445 va_list p;
3446{
3447 /* Total size in bytes of all the stack-parms scanned so far. */
3448 struct args_size args_size;
3449 /* Size of arguments before any adjustments (such as rounding). */
3450 struct args_size original_args_size;
3451 int argnum;
3452 rtx fun;
3453 int inc;
3454 int count;
3455 struct args_size alignment_pad;
3456 rtx argblock = 0;
3457 CUMULATIVE_ARGS args_so_far;
3458 struct arg
3459 {
3460 rtx value;
3461 enum machine_mode mode;
3462 rtx reg;
3463 int partial;
3464 struct args_size offset;
3465 struct args_size size;
3466 rtx save_area;
3467 };
3468 struct arg *argvec;
3469 int old_inhibit_defer_pop = inhibit_defer_pop;
3470 rtx call_fusage = 0;
3471 rtx mem_value = 0;
3472 rtx valreg;
3473 int pcc_struct_value = 0;
3474 int struct_value_size = 0;
3475 int flags;
3476 int reg_parm_stack_space = 0;
3477 int needed;
3478 rtx before_call;
3479
3480#ifdef REG_PARM_STACK_SPACE
3481 /* Define the boundary of the register parm stack space that needs to be
3482 save, if any. */
3483 int low_to_save = -1, high_to_save = 0;
3484 rtx save_area = 0; /* Place that it is saved. */
3485#endif
3486
3487 /* Size of the stack reserved for parameter registers. */
3488 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3489 char *initial_stack_usage_map = stack_usage_map;
3490
3491#ifdef REG_PARM_STACK_SPACE
3492#ifdef MAYBE_REG_PARM_STACK_SPACE
3493 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
3494#else
3495 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3496#endif
3497#endif
3498
3499 /* By default, library functions can not throw. */
3500 flags = ECF_NOTHROW;
3501
3502 switch (fn_type)
3503 {
3504 case LCT_NORMAL:
3505 break;
3506 case LCT_CONST:
3507 flags |= ECF_CONST;
3508 break;
3509 case LCT_PURE:
3510 flags |= ECF_PURE;
3511 break;
3512 case LCT_CONST_MAKE_BLOCK:
3513 flags |= ECF_CONST | ECF_LIBCALL_BLOCK;
3514 break;
3515 case LCT_PURE_MAKE_BLOCK:
3516 flags |= ECF_PURE | ECF_LIBCALL_BLOCK;
3517 break;
3518 case LCT_NORETURN:
3519 flags |= ECF_NORETURN;
3520 break;
3521 case LCT_THROW:
3522 flags = ECF_NORETURN;
3523 break;
3524 case LCT_ALWAYS_RETURN:
3525 flags = ECF_ALWAYS_RETURN;
3526 break;
3527 case LCT_RETURNS_TWICE:
3528 flags = ECF_RETURNS_TWICE;
3529 break;
3530 }
3531 fun = orgfun;
3532
3533 /* Ensure current function's preferred stack boundary is at least
3534 what we need. */
3535 if (cfun->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3536 cfun->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3537
3538 /* If this kind of value comes back in memory,
3539 decide where in memory it should come back. */
3540 if (outmode != VOIDmode && aggregate_value_p (type_for_mode (outmode, 0)))
3541 {
3542#ifdef PCC_STATIC_STRUCT_RETURN
3543 rtx pointer_reg
3544 = hard_function_value (build_pointer_type (type_for_mode (outmode, 0)),
3545 0, 0);
3546 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3547 pcc_struct_value = 1;
3548 if (value == 0)
3549 value = gen_reg_rtx (outmode);
3550#else /* not PCC_STATIC_STRUCT_RETURN */
3551 struct_value_size = GET_MODE_SIZE (outmode);
3552 if (value != 0 && GET_CODE (value) == MEM)
3553 mem_value = value;
3554 else
3555 mem_value = assign_temp (type_for_mode (outmode, 0), 0, 1, 1);
3556#endif
3557
3558 /* This call returns a big structure. */
3559 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
3560 }
3561
3562 /* ??? Unfinished: must pass the memory address as an argument. */
3563
3564 /* Copy all the libcall-arguments out of the varargs data
3565 and into a vector ARGVEC.
3566
3567 Compute how to pass each argument. We only support a very small subset
3568 of the full argument passing conventions to limit complexity here since
3569 library functions shouldn't have many args. */
3570
3571 argvec = (struct arg *) alloca ((nargs + 1) * sizeof (struct arg));
3572 memset ((char *) argvec, 0, (nargs + 1) * sizeof (struct arg));
3573
3574#ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3575 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far, outmode, fun);
3576#else
3577 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun, 0);
3578#endif
3579
3580 args_size.constant = 0;
3581 args_size.var = 0;
3582
3583 count = 0;
3584
3585 /* Now we are about to start emitting insns that can be deleted
3586 if a libcall is deleted. */
3587 if (flags & ECF_LIBCALL_BLOCK)
3588 start_sequence ();
3589
3590 push_temp_slots ();
3591
3592 /* If there's a structure value address to be passed,
3593 either pass it in the special place, or pass it as an extra argument. */
3594 if (mem_value && struct_value_rtx == 0 && ! pcc_struct_value)
3595 {
3596 rtx addr = XEXP (mem_value, 0);
3597 nargs++;
3598
3599 /* Make sure it is a reasonable operand for a move or push insn. */
3600 if (GET_CODE (addr) != REG && GET_CODE (addr) != MEM
3601 && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
3602 addr = force_operand (addr, NULL_RTX);
3603
3604 argvec[count].value = addr;
3605 argvec[count].mode = Pmode;
3606 argvec[count].partial = 0;
3607
3608 argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
3609#ifdef FUNCTION_ARG_PARTIAL_NREGS
3610 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far, Pmode, NULL_TREE, 1))
3611 abort ();
3612#endif
3613
3614 locate_and_pad_parm (Pmode, NULL_TREE,
3615#ifdef STACK_PARMS_IN_REG_PARM_AREA
3616 1,
3617#else
3618 argvec[count].reg != 0,
3619#endif
3620 NULL_TREE, &args_size, &argvec[count].offset,
3621 &argvec[count].size, &alignment_pad);
3622
3623 if (argvec[count].reg == 0 || argvec[count].partial != 0
3624 || reg_parm_stack_space > 0)
3625 args_size.constant += argvec[count].size.constant;
3626
3627 FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree) 0, 1);
3628
3629 count++;
3630 }
3631
3632 for (; count < nargs; count++)
3633 {
3634 rtx val = va_arg (p, rtx);
3635 enum machine_mode mode = va_arg (p, enum machine_mode);
3636
3637 /* We cannot convert the arg value to the mode the library wants here;
3638 must do it earlier where we know the signedness of the arg. */
3639 if (mode == BLKmode
3640 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
3641 abort ();
3642
3643 /* On some machines, there's no way to pass a float to a library fcn.
3644 Pass it as a double instead. */
3645#ifdef LIBGCC_NEEDS_DOUBLE
3646 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
3647 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
3648#endif
3649
3650 /* There's no need to call protect_from_queue, because
3651 either emit_move_insn or emit_push_insn will do that. */
3652
3653 /* Make sure it is a reasonable operand for a move or push insn. */
3654 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
3655 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
3656 val = force_operand (val, NULL_RTX);
3657
3658#ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3659 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
3660 {
3661 rtx slot;
3662 int must_copy = 1
3663#ifdef FUNCTION_ARG_CALLEE_COPIES
3664 && ! FUNCTION_ARG_CALLEE_COPIES (args_so_far, mode,
3665 NULL_TREE, 1)
3666#endif
3667 ;
3668
3669 if (GET_MODE (val) == MEM && ! must_copy)
3670 slot = val;
3671 else if (must_copy)
3672 {
3673 slot = assign_temp (type_for_mode (mode, 0), 0, 1, 1);
3674 emit_move_insn (slot, val);
3675 }
3676 else
3677 {
3678 tree type = type_for_mode (mode, 0);
3679
3680 slot = gen_rtx_MEM (mode,
3681 expand_expr (build1 (ADDR_EXPR,
3682 build_pointer_type
3683 (type),
3684 make_tree (type, val)),
3685 NULL_RTX, VOIDmode, 0));
3686 }
3687
3688 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3689 gen_rtx_USE (VOIDmode, slot),
3690 call_fusage);
3691 if (must_copy)
3692 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3693 gen_rtx_CLOBBER (VOIDmode,
3694 slot),
3695 call_fusage);
3696
3697 mode = Pmode;
3698 val = force_operand (XEXP (slot, 0), NULL_RTX);
3699 }
3700#endif
3701
3702 argvec[count].value = val;
3703 argvec[count].mode = mode;
3704
3705 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
3706
3707#ifdef FUNCTION_ARG_PARTIAL_NREGS
3708 argvec[count].partial
3709 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
3710#else
3711 argvec[count].partial = 0;
3712#endif
3713
3714 locate_and_pad_parm (mode, NULL_TREE,
3715#ifdef STACK_PARMS_IN_REG_PARM_AREA
3716 1,
3717#else
3718 argvec[count].reg != 0,
3719#endif
3720 NULL_TREE, &args_size, &argvec[count].offset,
3721 &argvec[count].size, &alignment_pad);
3722
3723 if (argvec[count].size.var)
3724 abort ();
3725
3726 if (reg_parm_stack_space == 0 && argvec[count].partial)
3727 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
3728
3729 if (argvec[count].reg == 0 || argvec[count].partial != 0
3730 || reg_parm_stack_space > 0)
3731 args_size.constant += argvec[count].size.constant;
3732
3733 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree) 0, 1);
3734 }
3735
3736#ifdef FINAL_REG_PARM_STACK_SPACE
3737 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
3738 args_size.var);
3739#endif
3740 /* If this machine requires an external definition for library
3741 functions, write one out. */
3742 assemble_external_libcall (fun);
3743
3744 original_args_size = args_size;
3745 args_size.constant = (((args_size.constant
3746 + stack_pointer_delta
3747 + STACK_BYTES - 1)
3748 / STACK_BYTES
3749 * STACK_BYTES)
3750 - stack_pointer_delta);
3751
3752 args_size.constant = MAX (args_size.constant,
3753 reg_parm_stack_space);
3754
3755#ifndef OUTGOING_REG_PARM_STACK_SPACE
3756 args_size.constant -= reg_parm_stack_space;
3757#endif
3758
3759 if (args_size.constant > current_function_outgoing_args_size)
3760 current_function_outgoing_args_size = args_size.constant;
3761
3762 if (ACCUMULATE_OUTGOING_ARGS)
3763 {
3764 /* Since the stack pointer will never be pushed, it is possible for
3765 the evaluation of a parm to clobber something we have already
3766 written to the stack. Since most function calls on RISC machines
3767 do not use the stack, this is uncommon, but must work correctly.
3768
3769 Therefore, we save any area of the stack that was already written
3770 and that we are using. Here we set up to do this by making a new
3771 stack usage map from the old one.
3772
3773 Another approach might be to try to reorder the argument
3774 evaluations to avoid this conflicting stack usage. */
3775
3776 needed = args_size.constant;
3777
3778#ifndef OUTGOING_REG_PARM_STACK_SPACE
3779 /* Since we will be writing into the entire argument area, the
3780 map must be allocated for its entire size, not just the part that
3781 is the responsibility of the caller. */
3782 needed += reg_parm_stack_space;
3783#endif
3784
3785#ifdef ARGS_GROW_DOWNWARD
3786 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3787 needed + 1);
3788#else
3789 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3790 needed);
3791#endif
3792 stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
3793
3794 if (initial_highest_arg_in_use)
3795 memcpy (stack_usage_map, initial_stack_usage_map,
3796 initial_highest_arg_in_use);
3797
3798 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3799 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
3800 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
3801 needed = 0;
3802
3803 /* We must be careful to use virtual regs before they're instantiated,
3804 and real regs afterwards. Loop optimization, for example, can create
3805 new libcalls after we've instantiated the virtual regs, and if we
3806 use virtuals anyway, they won't match the rtl patterns. */
3807
3808 if (virtuals_instantiated)
3809 argblock = plus_constant (stack_pointer_rtx, STACK_POINTER_OFFSET);
3810 else
3811 argblock = virtual_outgoing_args_rtx;
3812 }
3813 else
3814 {
3815 if (!PUSH_ARGS)
3816 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
3817 }
3818
3819 /* If we push args individually in reverse order, perform stack alignment
3820 before the first push (the last arg). */
3821 if (argblock == 0 && PUSH_ARGS_REVERSED)
3822 anti_adjust_stack (GEN_INT (args_size.constant
3823 - original_args_size.constant));
3824
3825 if (PUSH_ARGS_REVERSED)
3826 {
3827 inc = -1;
3828 argnum = nargs - 1;
3829 }
3830 else
3831 {
3832 inc = 1;
3833 argnum = 0;
3834 }
3835
3836#ifdef REG_PARM_STACK_SPACE
3837 if (ACCUMULATE_OUTGOING_ARGS)
3838 {
3839 /* The argument list is the property of the called routine and it
3840 may clobber it. If the fixed area has been used for previous
3841 parameters, we must save and restore it.
3842
3843 Here we compute the boundary of the that needs to be saved, if any. */
3844
3845#ifdef ARGS_GROW_DOWNWARD
3846 for (count = 0; count < reg_parm_stack_space + 1; count++)
3847#else
3848 for (count = 0; count < reg_parm_stack_space; count++)
3849#endif
3850 {
3851 if (count >= highest_outgoing_arg_in_use
3852 || stack_usage_map[count] == 0)
3853 continue;
3854
3855 if (low_to_save == -1)
3856 low_to_save = count;
3857
3858 high_to_save = count;
3859 }
3860
3861 if (low_to_save >= 0)
3862 {
3863 int num_to_save = high_to_save - low_to_save + 1;
3864 enum machine_mode save_mode
3865 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
3866 rtx stack_area;
3867
3868 /* If we don't have the required alignment, must do this in BLKmode. */
3869 if ((low_to_save & (MIN (GET_MODE_SIZE (save_mode),
3870 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
3871 save_mode = BLKmode;
3872
3873#ifdef ARGS_GROW_DOWNWARD
3874 stack_area = gen_rtx_MEM (save_mode,
3875 memory_address (save_mode,
3876 plus_constant (argblock,
3877 -high_to_save)));
3878#else
3879 stack_area = gen_rtx_MEM (save_mode,
3880 memory_address (save_mode,
3881 plus_constant (argblock,
3882 low_to_save)));
3883#endif
3884 if (save_mode == BLKmode)
3885 {
3886 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
3887 set_mem_align (save_area, PARM_BOUNDARY);
3888 emit_block_move (validize_mem (save_area), stack_area,
3889 GEN_INT (num_to_save));
3890 }
3891 else
3892 {
3893 save_area = gen_reg_rtx (save_mode);
3894 emit_move_insn (save_area, stack_area);
3895 }
3896 }
3897 }
3898#endif
3899
3900 /* Push the args that need to be pushed. */
3901
3902 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3903 are to be pushed. */
3904 for (count = 0; count < nargs; count++, argnum += inc)
3905 {
3906 enum machine_mode mode = argvec[argnum].mode;
3907 rtx val = argvec[argnum].value;
3908 rtx reg = argvec[argnum].reg;
3909 int partial = argvec[argnum].partial;
3910 int lower_bound = 0, upper_bound = 0, i;
3911
3912 if (! (reg != 0 && partial == 0))
3913 {
3914 if (ACCUMULATE_OUTGOING_ARGS)
3915 {
3916 /* If this is being stored into a pre-allocated, fixed-size,
3917 stack area, save any previous data at that location. */
3918
3919#ifdef ARGS_GROW_DOWNWARD
3920 /* stack_slot is negative, but we want to index stack_usage_map
3921 with positive values. */
3922 upper_bound = -argvec[argnum].offset.constant + 1;
3923 lower_bound = upper_bound - argvec[argnum].size.constant;
3924#else
3925 lower_bound = argvec[argnum].offset.constant;
3926 upper_bound = lower_bound + argvec[argnum].size.constant;
3927#endif
3928
3929 for (i = lower_bound; i < upper_bound; i++)
3930 if (stack_usage_map[i]
3931 /* Don't store things in the fixed argument area at this
3932 point; it has already been saved. */
3933 && i > reg_parm_stack_space)
3934 break;
3935
3936 if (i != upper_bound)
3937 {
3938 /* We need to make a save area. See what mode we can make
3939 it. */
3940 enum machine_mode save_mode
3941 = mode_for_size (argvec[argnum].size.constant
3942 * BITS_PER_UNIT,
3943 MODE_INT, 1);
3944 rtx stack_area
3945 = gen_rtx_MEM
3946 (save_mode,
3947 memory_address
3948 (save_mode,
3949 plus_constant (argblock,
3950 argvec[argnum].offset.constant)));
3951 argvec[argnum].save_area = gen_reg_rtx (save_mode);
3952
3953 emit_move_insn (argvec[argnum].save_area, stack_area);
3954 }
3955 }
3956
3957 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, 0, partial, reg, 0,
3958 argblock, GEN_INT (argvec[argnum].offset.constant),
3959 reg_parm_stack_space, ARGS_SIZE_RTX (alignment_pad));
3960
3961 /* Now mark the segment we just used. */
3962 if (ACCUMULATE_OUTGOING_ARGS)
3963 for (i = lower_bound; i < upper_bound; i++)
3964 stack_usage_map[i] = 1;
3965
3966 NO_DEFER_POP;
3967 }
3968 }
3969
3970 /* If we pushed args in forward order, perform stack alignment
3971 after pushing the last arg. */
3972 if (argblock == 0 && !PUSH_ARGS_REVERSED)
3973 anti_adjust_stack (GEN_INT (args_size.constant
3974 - original_args_size.constant));
3975
3976 if (PUSH_ARGS_REVERSED)
3977 argnum = nargs - 1;
3978 else
3979 argnum = 0;
3980
3981 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0, 0);
3982
3983 /* Now load any reg parms into their regs. */
3984
3985 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3986 are to be pushed. */
3987 for (count = 0; count < nargs; count++, argnum += inc)
3988 {
3989 rtx val = argvec[argnum].value;
3990 rtx reg = argvec[argnum].reg;
3991 int partial = argvec[argnum].partial;
3992
3993 /* Handle calls that pass values in multiple non-contiguous
3994 locations. The PA64 has examples of this for library calls. */
3995 if (reg != 0 && GET_CODE (reg) == PARALLEL)
3996 emit_group_load (reg, val, GET_MODE_SIZE (GET_MODE (val)));
3997 else if (reg != 0 && partial == 0)
3998 emit_move_insn (reg, val);
3999
4000 NO_DEFER_POP;
4001 }
4002
4003 /* Any regs containing parms remain in use through the call. */
4004 for (count = 0; count < nargs; count++)
4005 {
4006 rtx reg = argvec[count].reg;
4007 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4008 use_group_regs (&call_fusage, reg);
4009 else if (reg != 0)
4010 use_reg (&call_fusage, reg);
4011 }
4012
4013 /* Pass the function the address in which to return a structure value. */
4014 if (mem_value != 0 && struct_value_rtx != 0 && ! pcc_struct_value)
4015 {
4016 emit_move_insn (struct_value_rtx,
4017 force_reg (Pmode,
4018 force_operand (XEXP (mem_value, 0),
4019 NULL_RTX)));
4020 if (GET_CODE (struct_value_rtx) == REG)
4021 use_reg (&call_fusage, struct_value_rtx);
4022 }
4023
4024 /* Don't allow popping to be deferred, since then
4025 cse'ing of library calls could delete a call and leave the pop. */
4026 NO_DEFER_POP;
4027 valreg = (mem_value == 0 && outmode != VOIDmode
4028 ? hard_libcall_value (outmode) : NULL_RTX);
4029
4030 /* Stack must be properly aligned now. */
4031 if (stack_pointer_delta & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1))
4032 abort ();
4033
4034 before_call = get_last_insn ();
4035
4036 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4037 will set inhibit_defer_pop to that value. */
4038 /* The return type is needed to decide how many bytes the function pops.
4039 Signedness plays no role in that, so for simplicity, we pretend it's
4040 always signed. We also assume that the list of arguments passed has
4041 no impact, so we pretend it is unknown. */
4042
4043 emit_call_1 (fun,
4044 get_identifier (XSTR (orgfun, 0)),
4045 build_function_type (outmode == VOIDmode ? void_type_node
4046 : type_for_mode (outmode, 0), NULL_TREE),
4047 original_args_size.constant, args_size.constant,
4048 struct_value_size,
4049 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
4050 valreg,
4051 old_inhibit_defer_pop + 1, call_fusage, flags, & args_so_far);
4052
4053 /* For calls to `setjmp', etc., inform flow.c it should complain
4054 if nonvolatile values are live. For functions that cannot return,
4055 inform flow that control does not fall through. */
4056
4057 if (flags & (ECF_NORETURN | ECF_LONGJMP))
4058 {
4059 /* The barrier note must be emitted
4060 immediately after the CALL_INSN. Some ports emit more than
4061 just a CALL_INSN above, so we must search for it here. */
4062
4063 rtx last = get_last_insn ();
4064 while (GET_CODE (last) != CALL_INSN)
4065 {
4066 last = PREV_INSN (last);
4067 /* There was no CALL_INSN? */
4068 if (last == before_call)
4069 abort ();
4070 }
4071
4072 emit_barrier_after (last);
4073 }
4074
4075 /* Now restore inhibit_defer_pop to its actual original value. */
4076 OK_DEFER_POP;
4077
4078 /* If call is cse'able, make appropriate pair of reg-notes around it.
4079 Test valreg so we don't crash; may safely ignore `const'
4080 if return type is void. Disable for PARALLEL return values, because
4081 we have no way to move such values into a pseudo register. */
4082 if (flags & ECF_LIBCALL_BLOCK)
4083 {
4084 rtx insns;
4085
4086 if (valreg == 0 || GET_CODE (valreg) == PARALLEL)
4087 {
4088 insns = get_insns ();
4089 end_sequence ();
4090 emit_insns (insns);
4091 }
4092 else
4093 {
4094 rtx note = 0;
4095 rtx temp = gen_reg_rtx (GET_MODE (valreg));
4096 int i;
4097
4098 /* Construct an "equal form" for the value which mentions all the
4099 arguments in order as well as the function name. */
4100 for (i = 0; i < nargs; i++)
4101 note = gen_rtx_EXPR_LIST (VOIDmode, argvec[i].value, note);
4102 note = gen_rtx_EXPR_LIST (VOIDmode, fun, note);
4103
4104 insns = get_insns ();
4105 end_sequence ();
4106
4107 if (flags & ECF_PURE)
4108 note = gen_rtx_EXPR_LIST (VOIDmode,
4109 gen_rtx_USE (VOIDmode,
4110 gen_rtx_MEM (BLKmode,
4111 gen_rtx_SCRATCH (VOIDmode))),
4112 note);
4113
4114 emit_libcall_block (insns, temp, valreg, note);
4115
4116 valreg = temp;
4117 }
4118 }
4119 pop_temp_slots ();
4120
4121 /* Copy the value to the right place. */
4122 if (outmode != VOIDmode && retval)
4123 {
4124 if (mem_value)
4125 {
4126 if (value == 0)
4127 value = mem_value;
4128 if (value != mem_value)
4129 emit_move_insn (value, mem_value);
4130 }
4131 else if (value != 0)
4132 emit_move_insn (value, hard_libcall_value (outmode));
4133 else
4134 value = hard_libcall_value (outmode);
4135 }
4136
4137 if (ACCUMULATE_OUTGOING_ARGS)
4138 {
4139#ifdef REG_PARM_STACK_SPACE
4140 if (save_area)
4141 {
4142 enum machine_mode save_mode = GET_MODE (save_area);
4143#ifdef ARGS_GROW_DOWNWARD
4144 rtx stack_area
4145 = gen_rtx_MEM (save_mode,
4146 memory_address (save_mode,
4147 plus_constant (argblock,
4148 - high_to_save)));
4149#else
4150 rtx stack_area
4151 = gen_rtx_MEM (save_mode,
4152 memory_address (save_mode,
4153 plus_constant (argblock, low_to_save)));
4154#endif
4155
4156 set_mem_align (stack_area, PARM_BOUNDARY);
4157 if (save_mode != BLKmode)
4158 emit_move_insn (stack_area, save_area);
4159 else
4160 emit_block_move (stack_area, validize_mem (save_area),
4161 GEN_INT (high_to_save - low_to_save + 1));
4162 }
4163#endif
4164
4165 /* If we saved any argument areas, restore them. */
4166 for (count = 0; count < nargs; count++)
4167 if (argvec[count].save_area)
4168 {
4169 enum machine_mode save_mode = GET_MODE (argvec[count].save_area);
4170 rtx stack_area
4171 = gen_rtx_MEM (save_mode,
4172 memory_address
4173 (save_mode,
4174 plus_constant (argblock,
4175 argvec[count].offset.constant)));
4176
4177 emit_move_insn (stack_area, argvec[count].save_area);
4178 }
4179
4180 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4181 stack_usage_map = initial_stack_usage_map;
4182 }
4183
4184 return value;
4185
4186}
4187
4188/* Output a library call to function FUN (a SYMBOL_REF rtx)
4189 (emitting the queue unless NO_QUEUE is nonzero),
4190 for a value of mode OUTMODE,
4191 with NARGS different arguments, passed as alternating rtx values
4192 and machine_modes to convert them to.
4193 The rtx values should have been passed through protect_from_queue already.
4194
4195 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for `const'
4196 calls, LCT_PURE for `pure' calls, LCT_CONST_MAKE_BLOCK for `const' calls
4197 which should be enclosed in REG_LIBCALL/REG_RETVAL notes,
4198 LCT_PURE_MAKE_BLOCK for `purep' calls which should be enclosed in
4199 REG_LIBCALL/REG_RETVAL notes with extra (use (memory (scratch)),
4200 or other LCT_ value for other types of library calls. */
4201
4202void
4203emit_library_call VPARAMS((rtx orgfun, enum libcall_type fn_type,
4204 enum machine_mode outmode, int nargs, ...))
4205{
4206 VA_OPEN (p, nargs);
4207 VA_FIXEDARG (p, rtx, orgfun);
4208 VA_FIXEDARG (p, int, fn_type);
4209 VA_FIXEDARG (p, enum machine_mode, outmode);
4210 VA_FIXEDARG (p, int, nargs);
4211
4212 emit_library_call_value_1 (0, orgfun, NULL_RTX, fn_type, outmode, nargs, p);
4213
4214 VA_CLOSE (p);
4215}
4216
4217/* Like emit_library_call except that an extra argument, VALUE,
4218 comes second and says where to store the result.
4219 (If VALUE is zero, this function chooses a convenient way
4220 to return the value.
4221
4222 This function returns an rtx for where the value is to be found.
4223 If VALUE is nonzero, VALUE is returned. */
4224
4225rtx
4226emit_library_call_value VPARAMS((rtx orgfun, rtx value,
4227 enum libcall_type fn_type,
4228 enum machine_mode outmode, int nargs, ...))
4229{
4230 rtx result;
4231
4232 VA_OPEN (p, nargs);
4233 VA_FIXEDARG (p, rtx, orgfun);
4234 VA_FIXEDARG (p, rtx, value);
4235 VA_FIXEDARG (p, int, fn_type);
4236 VA_FIXEDARG (p, enum machine_mode, outmode);
4237 VA_FIXEDARG (p, int, nargs);
4238
4239 result = emit_library_call_value_1 (1, orgfun, value, fn_type, outmode,
4240 nargs, p);
4241
4242 VA_CLOSE (p);
4243
4244 return result;
4245}
4246
4247/* Store a single argument for a function call
4248 into the register or memory area where it must be passed.
4249 *ARG describes the argument value and where to pass it.
4250
4251 ARGBLOCK is the address of the stack-block for all the arguments,
4252 or 0 on a machine where arguments are pushed individually.
4253
4254 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4255 so must be careful about how the stack is used.
4256
4257 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4258 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4259 that we need not worry about saving and restoring the stack.
4260
4261 FNDECL is the declaration of the function we are calling.
4262
4263 Return non-zero if this arg should cause sibcall failure,
4264 zero otherwise. */
4265
4266static int
4267store_one_arg (arg, argblock, flags, variable_size, reg_parm_stack_space)
4268 struct arg_data *arg;
4269 rtx argblock;
4270 int flags;
4271 int variable_size ATTRIBUTE_UNUSED;
4272 int reg_parm_stack_space;
4273{
4274 tree pval = arg->tree_value;
4275 rtx reg = 0;
4276 int partial = 0;
4277 int used = 0;
4278 int i, lower_bound = 0, upper_bound = 0;
4279 int sibcall_failure = 0;
4280
4281 if (TREE_CODE (pval) == ERROR_MARK)
4282 return 1;
4283
4284 /* Push a new temporary level for any temporaries we make for
4285 this argument. */
4286 push_temp_slots ();
4287
4288 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
4289 {
4290 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4291 save any previous data at that location. */
4292 if (argblock && ! variable_size && arg->stack)
4293 {
4294#ifdef ARGS_GROW_DOWNWARD
4295 /* stack_slot is negative, but we want to index stack_usage_map
4296 with positive values. */
4297 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4298 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
4299 else
4300 upper_bound = 0;
4301
4302 lower_bound = upper_bound - arg->size.constant;
4303#else
4304 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4305 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
4306 else
4307 lower_bound = 0;
4308
4309 upper_bound = lower_bound + arg->size.constant;
4310#endif
4311
4312 for (i = lower_bound; i < upper_bound; i++)
4313 if (stack_usage_map[i]
4314 /* Don't store things in the fixed argument area at this point;
4315 it has already been saved. */
4316 && i > reg_parm_stack_space)
4317 break;
4318
4319 if (i != upper_bound)
4320 {
4321 /* We need to make a save area. See what mode we can make it. */
4322 enum machine_mode save_mode
4323 = mode_for_size (arg->size.constant * BITS_PER_UNIT, MODE_INT, 1);
4324 rtx stack_area
4325 = gen_rtx_MEM (save_mode,
4326 memory_address (save_mode,
4327 XEXP (arg->stack_slot, 0)));
4328
4329 if (save_mode == BLKmode)
4330 {
4331 tree ot = TREE_TYPE (arg->tree_value);
4332 tree nt = build_qualified_type (ot, (TYPE_QUALS (ot)
4333 | TYPE_QUAL_CONST));
4334
4335 arg->save_area = assign_temp (nt, 0, 1, 1);
4336 preserve_temp_slots (arg->save_area);
4337 emit_block_move (validize_mem (arg->save_area), stack_area,
4338 expr_size (arg->tree_value));
4339 }
4340 else
4341 {
4342 arg->save_area = gen_reg_rtx (save_mode);
4343 emit_move_insn (arg->save_area, stack_area);
4344 }
4345 }
4346 }
4347 /* Now that we have saved any slots that will be overwritten by this
4348 store, mark all slots this store will use. We must do this before
4349 we actually expand the argument since the expansion itself may
4350 trigger library calls which might need to use the same stack slot. */
4351 if (argblock && ! variable_size && arg->stack)
4352 for (i = lower_bound; i < upper_bound; i++)
4353 stack_usage_map[i] = 1;
4354 }
4355
4356 /* If this isn't going to be placed on both the stack and in registers,
4357 set up the register and number of words. */
4358 if (! arg->pass_on_stack)
4359 {
4360 if (flags & ECF_SIBCALL)
4361 reg = arg->tail_call_reg;
4362 else
4363 reg = arg->reg;
4364 partial = arg->partial;
4365 }
4366
4367 if (reg != 0 && partial == 0)
4368 /* Being passed entirely in a register. We shouldn't be called in
4369 this case. */
4370 abort ();
4371
4372 /* If this arg needs special alignment, don't load the registers
4373 here. */
4374 if (arg->n_aligned_regs != 0)
4375 reg = 0;
4376
4377 /* If this is being passed partially in a register, we can't evaluate
4378 it directly into its stack slot. Otherwise, we can. */
4379 if (arg->value == 0)
4380 {
4381 /* stack_arg_under_construction is nonzero if a function argument is
4382 being evaluated directly into the outgoing argument list and
4383 expand_call must take special action to preserve the argument list
4384 if it is called recursively.
4385
4386 For scalar function arguments stack_usage_map is sufficient to
4387 determine which stack slots must be saved and restored. Scalar
4388 arguments in general have pass_on_stack == 0.
4389
4390 If this argument is initialized by a function which takes the
4391 address of the argument (a C++ constructor or a C function
4392 returning a BLKmode structure), then stack_usage_map is
4393 insufficient and expand_call must push the stack around the
4394 function call. Such arguments have pass_on_stack == 1.
4395
4396 Note that it is always safe to set stack_arg_under_construction,
4397 but this generates suboptimal code if set when not needed. */
4398
4399 if (arg->pass_on_stack)
4400 stack_arg_under_construction++;
4401
4402 arg->value = expand_expr (pval,
4403 (partial
4404 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
4405 ? NULL_RTX : arg->stack,
4406 VOIDmode, 0);
4407
4408 /* If we are promoting object (or for any other reason) the mode
4409 doesn't agree, convert the mode. */
4410
4411 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
4412 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
4413 arg->value, arg->unsignedp);
4414
4415 if (arg->pass_on_stack)
4416 stack_arg_under_construction--;
4417 }
4418
4419 /* Don't allow anything left on stack from computation
4420 of argument to alloca. */
4421 if (flags & ECF_MAY_BE_ALLOCA)
4422 do_pending_stack_adjust ();
4423
4424 if (arg->value == arg->stack)
4425 /* If the value is already in the stack slot, we are done. */
4426 ;
4427 else if (arg->mode != BLKmode)
4428 {
4429 int size;
4430
4431 /* Argument is a scalar, not entirely passed in registers.
4432 (If part is passed in registers, arg->partial says how much
4433 and emit_push_insn will take care of putting it there.)
4434
4435 Push it, and if its size is less than the
4436 amount of space allocated to it,
4437 also bump stack pointer by the additional space.
4438 Note that in C the default argument promotions
4439 will prevent such mismatches. */
4440
4441 size = GET_MODE_SIZE (arg->mode);
4442 /* Compute how much space the push instruction will push.
4443 On many machines, pushing a byte will advance the stack
4444 pointer by a halfword. */
4445#ifdef PUSH_ROUNDING
4446 size = PUSH_ROUNDING (size);
4447#endif
4448 used = size;
4449
4450 /* Compute how much space the argument should get:
4451 round up to a multiple of the alignment for arguments. */
4452 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
4453 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
4454 / (PARM_BOUNDARY / BITS_PER_UNIT))
4455 * (PARM_BOUNDARY / BITS_PER_UNIT));
4456
4457 /* This isn't already where we want it on the stack, so put it there.
4458 This can either be done with push or copy insns. */
4459 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX, 0,
4460 partial, reg, used - size, argblock,
4461 ARGS_SIZE_RTX (arg->offset), reg_parm_stack_space,
4462 ARGS_SIZE_RTX (arg->alignment_pad));
4463
4464 /* Unless this is a partially-in-register argument, the argument is now
4465 in the stack. */
4466 if (partial == 0)
4467 arg->value = arg->stack;
4468 }
4469 else
4470 {
4471 /* BLKmode, at least partly to be pushed. */
4472
4473 int excess;
4474 rtx size_rtx;
4475
4476 /* Pushing a nonscalar.
4477 If part is passed in registers, PARTIAL says how much
4478 and emit_push_insn will take care of putting it there. */
4479
4480 /* Round its size up to a multiple
4481 of the allocation unit for arguments. */
4482
4483 if (arg->size.var != 0)
4484 {
4485 excess = 0;
4486 size_rtx = ARGS_SIZE_RTX (arg->size);
4487 }
4488 else
4489 {
4490 /* PUSH_ROUNDING has no effect on us, because
4491 emit_push_insn for BLKmode is careful to avoid it. */
4492 excess = (arg->size.constant - int_size_in_bytes (TREE_TYPE (pval))
4493 + partial * UNITS_PER_WORD);
4494 size_rtx = expand_expr (size_in_bytes (TREE_TYPE (pval)),
4495 NULL_RTX, TYPE_MODE (sizetype), 0);
4496 }
4497
4498 if ((flags & ECF_SIBCALL) && GET_CODE (arg->value) == MEM)
4499 {
4500 /* emit_push_insn might not work properly if arg->value and
4501 argblock + arg->offset areas overlap. */
4502 rtx x = arg->value;
4503 int i = 0;
4504
4505 if (XEXP (x, 0) == current_function_internal_arg_pointer
4506 || (GET_CODE (XEXP (x, 0)) == PLUS
4507 && XEXP (XEXP (x, 0), 0) ==
4508 current_function_internal_arg_pointer
4509 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT))
4510 {
4511 if (XEXP (x, 0) != current_function_internal_arg_pointer)
4512 i = INTVAL (XEXP (XEXP (x, 0), 1));
4513
4514 /* expand_call should ensure this */
4515 if (arg->offset.var || GET_CODE (size_rtx) != CONST_INT)
4516 abort ();
4517
4518 if (arg->offset.constant > i)
4519 {
4520 if (arg->offset.constant < i + INTVAL (size_rtx))
4521 sibcall_failure = 1;
4522 }
4523 else if (arg->offset.constant < i)
4524 {
4525 if (i < arg->offset.constant + INTVAL (size_rtx))
4526 sibcall_failure = 1;
4527 }
4528 }
4529 }
4530
4531 /* Special handling is required if part of the parameter lies in the
4532 register parameter area. The argument may be copied into the stack
4533 slot using memcpy(), but the original contents of the register
4534 parameter area will be restored after the memcpy() call.
4535
4536 To ensure that the part that lies in the register parameter area
4537 is copied correctly, we emit a separate push for that part. This
4538 push should be small enough to avoid a call to memcpy(). */
4539#ifndef STACK_PARMS_IN_REG_PARM_AREA
4540 if (arg->reg && arg->pass_on_stack)
4541#else
4542 if (1)
4543#endif
4544 {
4545 if (arg->offset.constant < reg_parm_stack_space && arg->offset.var)
4546 error ("variable offset is passed partially in stack and in reg");
4547 else if (arg->offset.constant < reg_parm_stack_space && arg->size.var)
4548 error ("variable size is passed partially in stack and in reg");
4549 else if (arg->offset.constant < reg_parm_stack_space
4550 && ((arg->offset.constant + arg->size.constant)
4551 > reg_parm_stack_space))
4552 {
4553 rtx size_rtx1 = GEN_INT (reg_parm_stack_space - arg->offset.constant);
4554 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx1,
4555 TYPE_ALIGN (TREE_TYPE (pval)), partial, reg,
4556 excess, argblock, ARGS_SIZE_RTX (arg->offset),
4557 reg_parm_stack_space,
4558 ARGS_SIZE_RTX (arg->alignment_pad));
4559 }
4560 }
4561
4562
4563 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
4564 TYPE_ALIGN (TREE_TYPE (pval)), partial, reg, excess,
4565 argblock, ARGS_SIZE_RTX (arg->offset),
4566 reg_parm_stack_space,
4567 ARGS_SIZE_RTX (arg->alignment_pad));
4568
4569 /* Unless this is a partially-in-register argument, the argument is now
4570 in the stack.
4571
4572 ??? Unlike the case above, in which we want the actual
4573 address of the data, so that we can load it directly into a
4574 register, here we want the address of the stack slot, so that
4575 it's properly aligned for word-by-word copying or something
4576 like that. It's not clear that this is always correct. */
4577 if (partial == 0)
4578 arg->value = arg->stack_slot;
4579 }
4580
4581 /* Once we have pushed something, pops can't safely
4582 be deferred during the rest of the arguments. */
4583 NO_DEFER_POP;
4584
4585 /* ANSI doesn't require a sequence point here,
4586 but PCC has one, so this will avoid some problems. */
4587 emit_queue ();
4588
4589 /* Free any temporary slots made in processing this argument. Show
4590 that we might have taken the address of something and pushed that
4591 as an operand. */
4592 preserve_temp_slots (NULL_RTX);
4593 free_temp_slots ();
4594 pop_temp_slots ();
4595
4596 return sibcall_failure;
4597}