* arm.md (addsf3, adddf3, subsf3, subdf3, mulsf3, muldf3, negsf2)
[official-gcc.git] / gcc / calls.c
blob509a689b0950cb4702c16d8effe063642be354fd
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, 2002, 2003 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
10 version.
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 for more details.
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
20 02111-1307, USA. */
22 #include "config.h"
23 #include "system.h"
24 #include "coretypes.h"
25 #include "tm.h"
26 #include "rtl.h"
27 #include "tree.h"
28 #include "flags.h"
29 #include "expr.h"
30 #include "libfuncs.h"
31 #include "function.h"
32 #include "regs.h"
33 #include "toplev.h"
34 #include "output.h"
35 #include "tm_p.h"
36 #include "timevar.h"
37 #include "sbitmap.h"
38 #include "langhooks.h"
39 #include "target.h"
40 #include "cgraph.h"
42 /* Decide whether a function's arguments should be processed
43 from first to last or from last to first.
45 They should if the stack and args grow in opposite directions, but
46 only if we have push insns. */
48 #ifdef PUSH_ROUNDING
50 #ifndef PUSH_ARGS_REVERSED
51 #if defined (STACK_GROWS_DOWNWARD) != defined (ARGS_GROW_DOWNWARD)
52 #define PUSH_ARGS_REVERSED PUSH_ARGS
53 #endif
54 #endif
56 #endif
58 #ifndef PUSH_ARGS_REVERSED
59 #define PUSH_ARGS_REVERSED 0
60 #endif
62 #ifndef STACK_POINTER_OFFSET
63 #define STACK_POINTER_OFFSET 0
64 #endif
66 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
67 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
69 /* Data structure and subroutines used within expand_call. */
71 struct arg_data
73 /* Tree node for this argument. */
74 tree tree_value;
75 /* Mode for value; TYPE_MODE unless promoted. */
76 enum machine_mode mode;
77 /* Current RTL value for argument, or 0 if it isn't precomputed. */
78 rtx value;
79 /* Initially-compute RTL value for argument; only for const functions. */
80 rtx initial_value;
81 /* Register to pass this argument in, 0 if passed on stack, or an
82 PARALLEL if the arg is to be copied into multiple non-contiguous
83 registers. */
84 rtx reg;
85 /* Register to pass this argument in when generating tail call sequence.
86 This is not the same register as for normal calls on machines with
87 register windows. */
88 rtx tail_call_reg;
89 /* If REG was promoted from the actual mode of the argument expression,
90 indicates whether the promotion is sign- or zero-extended. */
91 int unsignedp;
92 /* Number of registers to use. 0 means put the whole arg in registers.
93 Also 0 if not passed in registers. */
94 int partial;
95 /* Nonzero if argument must be passed on stack.
96 Note that some arguments may be passed on the stack
97 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
98 pass_on_stack identifies arguments that *cannot* go in registers. */
99 int pass_on_stack;
100 /* Offset of this argument from beginning of stack-args. */
101 struct args_size offset;
102 /* Similar, but offset to the start of the stack slot. Different from
103 OFFSET if this arg pads downward. */
104 struct args_size slot_offset;
105 /* Size of this argument on the stack, rounded up for any padding it gets,
106 parts of the argument passed in registers do not count.
107 If REG_PARM_STACK_SPACE is defined, then register parms
108 are counted here as well. */
109 struct args_size size;
110 /* Location on the stack at which parameter should be stored. The store
111 has already been done if STACK == VALUE. */
112 rtx stack;
113 /* Location on the stack of the start of this argument slot. This can
114 differ from STACK if this arg pads downward. This location is known
115 to be aligned to FUNCTION_ARG_BOUNDARY. */
116 rtx stack_slot;
117 /* Place that this stack area has been saved, if needed. */
118 rtx save_area;
119 /* If an argument's alignment does not permit direct copying into registers,
120 copy in smaller-sized pieces into pseudos. These are stored in a
121 block pointed to by this field. The next field says how many
122 word-sized pseudos we made. */
123 rtx *aligned_regs;
124 int n_aligned_regs;
125 /* The amount that the stack pointer needs to be adjusted to
126 force alignment for the next argument. */
127 struct args_size alignment_pad;
130 /* A vector of one char per byte of stack space. A byte if nonzero if
131 the corresponding stack location has been used.
132 This vector is used to prevent a function call within an argument from
133 clobbering any stack already set up. */
134 static char *stack_usage_map;
136 /* Size of STACK_USAGE_MAP. */
137 static int highest_outgoing_arg_in_use;
139 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
140 stack location's tail call argument has been already stored into the stack.
141 This bitmap is used to prevent sibling call optimization if function tries
142 to use parent's incoming argument slots when they have been already
143 overwritten with tail call arguments. */
144 static sbitmap stored_args_map;
146 /* stack_arg_under_construction is nonzero when an argument may be
147 initialized with a constructor call (including a C function that
148 returns a BLKmode struct) and expand_call must take special action
149 to make sure the object being constructed does not overlap the
150 argument list for the constructor call. */
151 int stack_arg_under_construction;
153 static int calls_function PARAMS ((tree, int));
154 static int calls_function_1 PARAMS ((tree, int));
156 static void emit_call_1 PARAMS ((rtx, tree, tree, HOST_WIDE_INT,
157 HOST_WIDE_INT, HOST_WIDE_INT, rtx,
158 rtx, int, rtx, int,
159 CUMULATIVE_ARGS *));
160 static void precompute_register_parameters PARAMS ((int,
161 struct arg_data *,
162 int *));
163 static int store_one_arg PARAMS ((struct arg_data *, rtx, int, int,
164 int));
165 static void store_unaligned_arguments_into_pseudos PARAMS ((struct arg_data *,
166 int));
167 static int finalize_must_preallocate PARAMS ((int, int,
168 struct arg_data *,
169 struct args_size *));
170 static void precompute_arguments PARAMS ((int, int,
171 struct arg_data *));
172 static int compute_argument_block_size PARAMS ((int,
173 struct args_size *,
174 int));
175 static void initialize_argument_information PARAMS ((int,
176 struct arg_data *,
177 struct args_size *,
178 int, tree, tree,
179 CUMULATIVE_ARGS *,
180 int, rtx *, int *,
181 int *, int *));
182 static void compute_argument_addresses PARAMS ((struct arg_data *,
183 rtx, int));
184 static rtx rtx_for_function_call PARAMS ((tree, tree));
185 static void load_register_parameters PARAMS ((struct arg_data *,
186 int, rtx *, int,
187 int, int *));
188 static rtx emit_library_call_value_1 PARAMS ((int, rtx, rtx,
189 enum libcall_type,
190 enum machine_mode,
191 int, va_list));
192 static int special_function_p PARAMS ((tree, int));
193 static rtx try_to_integrate PARAMS ((tree, tree, rtx,
194 int, tree, rtx));
195 static int check_sibcall_argument_overlap_1 PARAMS ((rtx));
196 static int check_sibcall_argument_overlap PARAMS ((rtx, struct arg_data *,
197 int));
199 static int combine_pending_stack_adjustment_and_call
200 PARAMS ((int, struct args_size *, int));
201 static tree fix_unsafe_tree PARAMS ((tree));
203 #ifdef REG_PARM_STACK_SPACE
204 static rtx save_fixed_argument_area PARAMS ((int, rtx, int *, int *));
205 static void restore_fixed_argument_area PARAMS ((rtx, rtx, int, int));
206 #endif
208 /* If WHICH is 1, return 1 if EXP contains a call to the built-in function
209 `alloca'.
211 If WHICH is 0, return 1 if EXP contains a call to any function.
212 Actually, we only need return 1 if evaluating EXP would require pushing
213 arguments on the stack, but that is too difficult to compute, so we just
214 assume any function call might require the stack. */
216 static tree calls_function_save_exprs;
218 static int
219 calls_function (exp, which)
220 tree exp;
221 int which;
223 int val;
225 calls_function_save_exprs = 0;
226 val = calls_function_1 (exp, which);
227 calls_function_save_exprs = 0;
228 return val;
231 /* Recursive function to do the work of above function. */
233 static int
234 calls_function_1 (exp, which)
235 tree exp;
236 int which;
238 int i;
239 enum tree_code code = TREE_CODE (exp);
240 int class = TREE_CODE_CLASS (code);
241 int length = first_rtl_op (code);
243 /* If this code is language-specific, we don't know what it will do. */
244 if ((int) code >= NUM_TREE_CODES)
245 return 1;
247 switch (code)
249 case CALL_EXPR:
250 if (which == 0)
251 return 1;
252 else if ((TREE_CODE (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))
253 == FUNCTION_TYPE)
254 && (TYPE_RETURNS_STACK_DEPRESSED
255 (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))))
256 return 1;
257 else if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
258 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
259 == FUNCTION_DECL)
260 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp, 0), 0),
262 & ECF_MAY_BE_ALLOCA))
263 return 1;
265 break;
267 case CONSTRUCTOR:
269 tree tem;
271 for (tem = CONSTRUCTOR_ELTS (exp); tem != 0; tem = TREE_CHAIN (tem))
272 if (calls_function_1 (TREE_VALUE (tem), which))
273 return 1;
276 return 0;
278 case SAVE_EXPR:
279 if (SAVE_EXPR_RTL (exp) != 0)
280 return 0;
281 if (value_member (exp, calls_function_save_exprs))
282 return 0;
283 calls_function_save_exprs = tree_cons (NULL_TREE, exp,
284 calls_function_save_exprs);
285 return (TREE_OPERAND (exp, 0) != 0
286 && calls_function_1 (TREE_OPERAND (exp, 0), which));
288 case BLOCK:
290 tree local;
291 tree subblock;
293 for (local = BLOCK_VARS (exp); local; local = TREE_CHAIN (local))
294 if (DECL_INITIAL (local) != 0
295 && calls_function_1 (DECL_INITIAL (local), which))
296 return 1;
298 for (subblock = BLOCK_SUBBLOCKS (exp);
299 subblock;
300 subblock = TREE_CHAIN (subblock))
301 if (calls_function_1 (subblock, which))
302 return 1;
304 return 0;
306 case TREE_LIST:
307 for (; exp != 0; exp = TREE_CHAIN (exp))
308 if (calls_function_1 (TREE_VALUE (exp), which))
309 return 1;
310 return 0;
312 default:
313 break;
316 /* Only expressions, references, and blocks can contain calls. */
317 if (! IS_EXPR_CODE_CLASS (class) && class != 'r' && class != 'b')
318 return 0;
320 for (i = 0; i < length; i++)
321 if (TREE_OPERAND (exp, i) != 0
322 && calls_function_1 (TREE_OPERAND (exp, i), which))
323 return 1;
325 return 0;
328 /* Force FUNEXP into a form suitable for the address of a CALL,
329 and return that as an rtx. Also load the static chain register
330 if FNDECL is a nested function.
332 CALL_FUSAGE points to a variable holding the prospective
333 CALL_INSN_FUNCTION_USAGE information. */
336 prepare_call_address (funexp, fndecl, call_fusage, reg_parm_seen, sibcallp)
337 rtx funexp;
338 tree fndecl;
339 rtx *call_fusage;
340 int reg_parm_seen;
341 int sibcallp;
343 rtx static_chain_value = 0;
345 funexp = protect_from_queue (funexp, 0);
347 if (fndecl != 0)
348 /* Get possible static chain value for nested function in C. */
349 static_chain_value = lookup_static_chain (fndecl);
351 /* Make a valid memory address and copy constants thru pseudo-regs,
352 but not for a constant address if -fno-function-cse. */
353 if (GET_CODE (funexp) != SYMBOL_REF)
354 /* If we are using registers for parameters, force the
355 function address into a register now. */
356 funexp = ((SMALL_REGISTER_CLASSES && reg_parm_seen)
357 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
358 : memory_address (FUNCTION_MODE, funexp));
359 else if (! sibcallp)
361 #ifndef NO_FUNCTION_CSE
362 if (optimize && ! flag_no_function_cse)
363 #ifdef NO_RECURSIVE_FUNCTION_CSE
364 if (fndecl != current_function_decl)
365 #endif
366 funexp = force_reg (Pmode, funexp);
367 #endif
370 if (static_chain_value != 0)
372 emit_move_insn (static_chain_rtx, static_chain_value);
374 if (GET_CODE (static_chain_rtx) == REG)
375 use_reg (call_fusage, static_chain_rtx);
378 return funexp;
381 /* Generate instructions to call function FUNEXP,
382 and optionally pop the results.
383 The CALL_INSN is the first insn generated.
385 FNDECL is the declaration node of the function. This is given to the
386 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
388 FUNTYPE is the data type of the function. This is given to the macro
389 RETURN_POPS_ARGS to determine whether this function pops its own args.
390 We used to allow an identifier for library functions, but that doesn't
391 work when the return type is an aggregate type and the calling convention
392 says that the pointer to this aggregate is to be popped by the callee.
394 STACK_SIZE is the number of bytes of arguments on the stack,
395 ROUNDED_STACK_SIZE is that number rounded up to
396 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
397 both to put into the call insn and to generate explicit popping
398 code if necessary.
400 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
401 It is zero if this call doesn't want a structure value.
403 NEXT_ARG_REG is the rtx that results from executing
404 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
405 just after all the args have had their registers assigned.
406 This could be whatever you like, but normally it is the first
407 arg-register beyond those used for args in this call,
408 or 0 if all the arg-registers are used in this call.
409 It is passed on to `gen_call' so you can put this info in the call insn.
411 VALREG is a hard register in which a value is returned,
412 or 0 if the call does not return a value.
414 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
415 the args to this call were processed.
416 We restore `inhibit_defer_pop' to that value.
418 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
419 denote registers used by the called function. */
421 static void
422 emit_call_1 (funexp, fndecl, funtype, stack_size, rounded_stack_size,
423 struct_value_size, next_arg_reg, valreg, old_inhibit_defer_pop,
424 call_fusage, ecf_flags, args_so_far)
425 rtx funexp;
426 tree fndecl ATTRIBUTE_UNUSED;
427 tree funtype ATTRIBUTE_UNUSED;
428 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED;
429 HOST_WIDE_INT rounded_stack_size;
430 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED;
431 rtx next_arg_reg ATTRIBUTE_UNUSED;
432 rtx valreg;
433 int old_inhibit_defer_pop;
434 rtx call_fusage;
435 int ecf_flags;
436 CUMULATIVE_ARGS *args_so_far ATTRIBUTE_UNUSED;
438 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
439 rtx call_insn;
440 int already_popped = 0;
441 HOST_WIDE_INT n_popped = RETURN_POPS_ARGS (fndecl, funtype, stack_size);
442 #if defined (HAVE_call) && defined (HAVE_call_value)
443 rtx struct_value_size_rtx;
444 struct_value_size_rtx = GEN_INT (struct_value_size);
445 #endif
447 #ifdef CALL_POPS_ARGS
448 n_popped += CALL_POPS_ARGS (* args_so_far);
449 #endif
451 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
452 and we don't want to load it into a register as an optimization,
453 because prepare_call_address already did it if it should be done. */
454 if (GET_CODE (funexp) != SYMBOL_REF)
455 funexp = memory_address (FUNCTION_MODE, funexp);
457 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
458 if ((ecf_flags & ECF_SIBCALL)
459 && HAVE_sibcall_pop && HAVE_sibcall_value_pop
460 && (n_popped > 0 || stack_size == 0))
462 rtx n_pop = GEN_INT (n_popped);
463 rtx pat;
465 /* If this subroutine pops its own args, record that in the call insn
466 if possible, for the sake of frame pointer elimination. */
468 if (valreg)
469 pat = GEN_SIBCALL_VALUE_POP (valreg,
470 gen_rtx_MEM (FUNCTION_MODE, funexp),
471 rounded_stack_size_rtx, next_arg_reg,
472 n_pop);
473 else
474 pat = GEN_SIBCALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
475 rounded_stack_size_rtx, next_arg_reg, n_pop);
477 emit_call_insn (pat);
478 already_popped = 1;
480 else
481 #endif
483 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
484 /* If the target has "call" or "call_value" insns, then prefer them
485 if no arguments are actually popped. If the target does not have
486 "call" or "call_value" insns, then we must use the popping versions
487 even if the call has no arguments to pop. */
488 #if defined (HAVE_call) && defined (HAVE_call_value)
489 if (HAVE_call && HAVE_call_value && HAVE_call_pop && HAVE_call_value_pop
490 && n_popped > 0 && ! (ecf_flags & ECF_SP_DEPRESSED))
491 #else
492 if (HAVE_call_pop && HAVE_call_value_pop)
493 #endif
495 rtx n_pop = GEN_INT (n_popped);
496 rtx pat;
498 /* If this subroutine pops its own args, record that in the call insn
499 if possible, for the sake of frame pointer elimination. */
501 if (valreg)
502 pat = GEN_CALL_VALUE_POP (valreg,
503 gen_rtx_MEM (FUNCTION_MODE, funexp),
504 rounded_stack_size_rtx, next_arg_reg, n_pop);
505 else
506 pat = GEN_CALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
507 rounded_stack_size_rtx, next_arg_reg, n_pop);
509 emit_call_insn (pat);
510 already_popped = 1;
512 else
513 #endif
515 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
516 if ((ecf_flags & ECF_SIBCALL)
517 && HAVE_sibcall && HAVE_sibcall_value)
519 if (valreg)
520 emit_call_insn (GEN_SIBCALL_VALUE (valreg,
521 gen_rtx_MEM (FUNCTION_MODE, funexp),
522 rounded_stack_size_rtx,
523 next_arg_reg, NULL_RTX));
524 else
525 emit_call_insn (GEN_SIBCALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
526 rounded_stack_size_rtx, next_arg_reg,
527 struct_value_size_rtx));
529 else
530 #endif
532 #if defined (HAVE_call) && defined (HAVE_call_value)
533 if (HAVE_call && HAVE_call_value)
535 if (valreg)
536 emit_call_insn (GEN_CALL_VALUE (valreg,
537 gen_rtx_MEM (FUNCTION_MODE, funexp),
538 rounded_stack_size_rtx, next_arg_reg,
539 NULL_RTX));
540 else
541 emit_call_insn (GEN_CALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
542 rounded_stack_size_rtx, next_arg_reg,
543 struct_value_size_rtx));
545 else
546 #endif
547 abort ();
549 /* Find the CALL insn we just emitted. */
550 for (call_insn = get_last_insn ();
551 call_insn && GET_CODE (call_insn) != CALL_INSN;
552 call_insn = PREV_INSN (call_insn))
555 if (! call_insn)
556 abort ();
558 /* Mark memory as used for "pure" function call. */
559 if (ecf_flags & ECF_PURE)
560 call_fusage
561 = gen_rtx_EXPR_LIST
562 (VOIDmode,
563 gen_rtx_USE (VOIDmode,
564 gen_rtx_MEM (BLKmode, gen_rtx_SCRATCH (VOIDmode))),
565 call_fusage);
567 /* Put the register usage information on the CALL. If there is already
568 some usage information, put ours at the end. */
569 if (CALL_INSN_FUNCTION_USAGE (call_insn))
571 rtx link;
573 for (link = CALL_INSN_FUNCTION_USAGE (call_insn); XEXP (link, 1) != 0;
574 link = XEXP (link, 1))
577 XEXP (link, 1) = call_fusage;
579 else
580 CALL_INSN_FUNCTION_USAGE (call_insn) = call_fusage;
582 /* If this is a const call, then set the insn's unchanging bit. */
583 if (ecf_flags & (ECF_CONST | ECF_PURE))
584 CONST_OR_PURE_CALL_P (call_insn) = 1;
586 /* If this call can't throw, attach a REG_EH_REGION reg note to that
587 effect. */
588 if (ecf_flags & ECF_NOTHROW)
589 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_EH_REGION, const0_rtx,
590 REG_NOTES (call_insn));
592 if (ecf_flags & ECF_NORETURN)
593 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_NORETURN, const0_rtx,
594 REG_NOTES (call_insn));
595 if (ecf_flags & ECF_ALWAYS_RETURN)
596 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_ALWAYS_RETURN, const0_rtx,
597 REG_NOTES (call_insn));
599 if (ecf_flags & ECF_RETURNS_TWICE)
601 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_SETJMP, const0_rtx,
602 REG_NOTES (call_insn));
603 current_function_calls_setjmp = 1;
606 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
608 /* Restore this now, so that we do defer pops for this call's args
609 if the context of the call as a whole permits. */
610 inhibit_defer_pop = old_inhibit_defer_pop;
612 if (n_popped > 0)
614 if (!already_popped)
615 CALL_INSN_FUNCTION_USAGE (call_insn)
616 = gen_rtx_EXPR_LIST (VOIDmode,
617 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
618 CALL_INSN_FUNCTION_USAGE (call_insn));
619 rounded_stack_size -= n_popped;
620 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
621 stack_pointer_delta -= n_popped;
624 if (!ACCUMULATE_OUTGOING_ARGS)
626 /* If returning from the subroutine does not automatically pop the args,
627 we need an instruction to pop them sooner or later.
628 Perhaps do it now; perhaps just record how much space to pop later.
630 If returning from the subroutine does pop the args, indicate that the
631 stack pointer will be changed. */
633 if (rounded_stack_size != 0)
635 if (ecf_flags & ECF_SP_DEPRESSED)
636 /* Just pretend we did the pop. */
637 stack_pointer_delta -= rounded_stack_size;
638 else if (flag_defer_pop && inhibit_defer_pop == 0
639 && ! (ecf_flags & (ECF_CONST | ECF_PURE)))
640 pending_stack_adjust += rounded_stack_size;
641 else
642 adjust_stack (rounded_stack_size_rtx);
645 /* When we accumulate outgoing args, we must avoid any stack manipulations.
646 Restore the stack pointer to its original value now. Usually
647 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
648 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
649 popping variants of functions exist as well.
651 ??? We may optimize similar to defer_pop above, but it is
652 probably not worthwhile.
654 ??? It will be worthwhile to enable combine_stack_adjustments even for
655 such machines. */
656 else if (n_popped)
657 anti_adjust_stack (GEN_INT (n_popped));
660 /* Determine if the function identified by NAME and FNDECL is one with
661 special properties we wish to know about.
663 For example, if the function might return more than one time (setjmp), then
664 set RETURNS_TWICE to a nonzero value.
666 Similarly set LONGJMP for if the function is in the longjmp family.
668 Set MALLOC for any of the standard memory allocation functions which
669 allocate from the heap.
671 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
672 space from the stack such as alloca. */
674 static int
675 special_function_p (fndecl, flags)
676 tree fndecl;
677 int flags;
679 if (! (flags & ECF_MALLOC)
680 && fndecl && DECL_NAME (fndecl)
681 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 17
682 /* Exclude functions not at the file scope, or not `extern',
683 since they are not the magic functions we would otherwise
684 think they are. */
685 && DECL_CONTEXT (fndecl) == NULL_TREE && TREE_PUBLIC (fndecl))
687 const char *name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
688 const char *tname = name;
690 /* We assume that alloca will always be called by name. It
691 makes no sense to pass it as a pointer-to-function to
692 anything that does not understand its behavior. */
693 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
694 && name[0] == 'a'
695 && ! strcmp (name, "alloca"))
696 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
697 && name[0] == '_'
698 && ! strcmp (name, "__builtin_alloca"))))
699 flags |= ECF_MAY_BE_ALLOCA;
701 /* Disregard prefix _, __ or __x. */
702 if (name[0] == '_')
704 if (name[1] == '_' && name[2] == 'x')
705 tname += 3;
706 else if (name[1] == '_')
707 tname += 2;
708 else
709 tname += 1;
712 if (tname[0] == 's')
714 if ((tname[1] == 'e'
715 && (! strcmp (tname, "setjmp")
716 || ! strcmp (tname, "setjmp_syscall")))
717 || (tname[1] == 'i'
718 && ! strcmp (tname, "sigsetjmp"))
719 || (tname[1] == 'a'
720 && ! strcmp (tname, "savectx")))
721 flags |= ECF_RETURNS_TWICE;
723 if (tname[1] == 'i'
724 && ! strcmp (tname, "siglongjmp"))
725 flags |= ECF_LONGJMP;
727 else if ((tname[0] == 'q' && tname[1] == 's'
728 && ! strcmp (tname, "qsetjmp"))
729 || (tname[0] == 'v' && tname[1] == 'f'
730 && ! strcmp (tname, "vfork")))
731 flags |= ECF_RETURNS_TWICE;
733 else if (tname[0] == 'l' && tname[1] == 'o'
734 && ! strcmp (tname, "longjmp"))
735 flags |= ECF_LONGJMP;
737 else if ((tname[0] == 'f' && tname[1] == 'o'
738 && ! strcmp (tname, "fork"))
739 /* Linux specific: __clone. check NAME to insist on the
740 leading underscores, to avoid polluting the ISO / POSIX
741 namespace. */
742 || (name[0] == '_' && name[1] == '_'
743 && ! strcmp (tname, "clone"))
744 || (tname[0] == 'e' && tname[1] == 'x' && tname[2] == 'e'
745 && tname[3] == 'c' && (tname[4] == 'l' || tname[4] == 'v')
746 && (tname[5] == '\0'
747 || ((tname[5] == 'p' || tname[5] == 'e')
748 && tname[6] == '\0'))))
749 flags |= ECF_FORK_OR_EXEC;
751 /* Do not add any more malloc-like functions to this list,
752 instead mark them as malloc functions using the malloc attribute.
753 Note, realloc is not suitable for attribute malloc since
754 it may return the same address across multiple calls.
755 C++ operator new is not suitable because it is not required
756 to return a unique pointer; indeed, the standard placement new
757 just returns its argument. */
758 else if (TYPE_MODE (TREE_TYPE (TREE_TYPE (fndecl))) == Pmode
759 && (! strcmp (tname, "malloc")
760 || ! strcmp (tname, "calloc")
761 || ! strcmp (tname, "strdup")))
762 flags |= ECF_MALLOC;
764 return flags;
767 /* Return nonzero when tree represent call to longjmp. */
770 setjmp_call_p (fndecl)
771 tree fndecl;
773 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
776 /* Return true when exp contains alloca call. */
777 bool
778 alloca_call_p (exp)
779 tree exp;
781 if (TREE_CODE (exp) == CALL_EXPR
782 && TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
783 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
784 == FUNCTION_DECL)
785 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp, 0), 0),
786 0) & ECF_MAY_BE_ALLOCA))
787 return true;
788 return false;
791 /* Detect flags (function attributes) from the function decl or type node. */
794 flags_from_decl_or_type (exp)
795 tree exp;
797 int flags = 0;
798 tree type = exp;
799 /* ??? We can't set IS_MALLOC for function types? */
800 if (DECL_P (exp))
802 struct cgraph_rtl_info *i = cgraph_rtl_info (exp);
803 type = TREE_TYPE (exp);
805 if (i && i->pure_function)
806 flags |= ECF_PURE | ECF_LIBCALL_BLOCK;
807 if (i && i->const_function)
808 flags |= ECF_CONST | ECF_LIBCALL_BLOCK;
810 /* The function exp may have the `malloc' attribute. */
811 if (DECL_P (exp) && DECL_IS_MALLOC (exp))
812 flags |= ECF_MALLOC;
814 /* The function exp may have the `pure' attribute. */
815 if (DECL_P (exp) && DECL_IS_PURE (exp))
816 flags |= ECF_PURE | ECF_LIBCALL_BLOCK;
818 if (TREE_NOTHROW (exp))
819 flags |= ECF_NOTHROW;
822 if (TREE_READONLY (exp) && ! TREE_THIS_VOLATILE (exp))
823 flags |= ECF_CONST | ECF_LIBCALL_BLOCK;
825 if (TREE_THIS_VOLATILE (exp))
826 flags |= ECF_NORETURN;
828 /* Mark if the function returns with the stack pointer depressed. We
829 cannot consider it pure or constant in that case. */
830 if (TREE_CODE (type) == FUNCTION_TYPE && TYPE_RETURNS_STACK_DEPRESSED (type))
832 flags |= ECF_SP_DEPRESSED;
833 flags &= ~(ECF_PURE | ECF_CONST | ECF_LIBCALL_BLOCK);
836 return flags;
839 /* Precompute all register parameters as described by ARGS, storing values
840 into fields within the ARGS array.
842 NUM_ACTUALS indicates the total number elements in the ARGS array.
844 Set REG_PARM_SEEN if we encounter a register parameter. */
846 static void
847 precompute_register_parameters (num_actuals, args, reg_parm_seen)
848 int num_actuals;
849 struct arg_data *args;
850 int *reg_parm_seen;
852 int i;
854 *reg_parm_seen = 0;
856 for (i = 0; i < num_actuals; i++)
857 if (args[i].reg != 0 && ! args[i].pass_on_stack)
859 *reg_parm_seen = 1;
861 if (args[i].value == 0)
863 push_temp_slots ();
864 args[i].value = expand_expr (args[i].tree_value, NULL_RTX,
865 VOIDmode, 0);
866 preserve_temp_slots (args[i].value);
867 pop_temp_slots ();
869 /* ANSI doesn't require a sequence point here,
870 but PCC has one, so this will avoid some problems. */
871 emit_queue ();
874 /* If the value is a non-legitimate constant, force it into a
875 pseudo now. TLS symbols sometimes need a call to resolve. */
876 if (CONSTANT_P (args[i].value)
877 && !LEGITIMATE_CONSTANT_P (args[i].value))
878 args[i].value = force_reg (args[i].mode, args[i].value);
880 /* If we are to promote the function arg to a wider mode,
881 do it now. */
883 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
884 args[i].value
885 = convert_modes (args[i].mode,
886 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
887 args[i].value, args[i].unsignedp);
889 /* If the value is expensive, and we are inside an appropriately
890 short loop, put the value into a pseudo and then put the pseudo
891 into the hard reg.
893 For small register classes, also do this if this call uses
894 register parameters. This is to avoid reload conflicts while
895 loading the parameters registers. */
897 if ((! (GET_CODE (args[i].value) == REG
898 || (GET_CODE (args[i].value) == SUBREG
899 && GET_CODE (SUBREG_REG (args[i].value)) == REG)))
900 && args[i].mode != BLKmode
901 && rtx_cost (args[i].value, SET) > COSTS_N_INSNS (1)
902 && ((SMALL_REGISTER_CLASSES && *reg_parm_seen)
903 || preserve_subexpressions_p ()))
904 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
908 #ifdef REG_PARM_STACK_SPACE
910 /* The argument list is the property of the called routine and it
911 may clobber it. If the fixed area has been used for previous
912 parameters, we must save and restore it. */
914 static rtx
915 save_fixed_argument_area (reg_parm_stack_space, argblock,
916 low_to_save, high_to_save)
917 int reg_parm_stack_space;
918 rtx argblock;
919 int *low_to_save;
920 int *high_to_save;
922 int low;
923 int high;
925 /* Compute the boundary of the area that needs to be saved, if any. */
926 high = reg_parm_stack_space;
927 #ifdef ARGS_GROW_DOWNWARD
928 high += 1;
929 #endif
930 if (high > highest_outgoing_arg_in_use)
931 high = highest_outgoing_arg_in_use;
933 for (low = 0; low < high; low++)
934 if (stack_usage_map[low] != 0)
936 int num_to_save;
937 enum machine_mode save_mode;
938 int delta;
939 rtx stack_area;
940 rtx save_area;
942 while (stack_usage_map[--high] == 0)
945 *low_to_save = low;
946 *high_to_save = high;
948 num_to_save = high - low + 1;
949 save_mode = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
951 /* If we don't have the required alignment, must do this
952 in BLKmode. */
953 if ((low & (MIN (GET_MODE_SIZE (save_mode),
954 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
955 save_mode = BLKmode;
957 #ifdef ARGS_GROW_DOWNWARD
958 delta = -high;
959 #else
960 delta = low;
961 #endif
962 stack_area = gen_rtx_MEM (save_mode,
963 memory_address (save_mode,
964 plus_constant (argblock,
965 delta)));
967 set_mem_align (stack_area, PARM_BOUNDARY);
968 if (save_mode == BLKmode)
970 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
971 emit_block_move (validize_mem (save_area), stack_area,
972 GEN_INT (num_to_save), BLOCK_OP_CALL_PARM);
974 else
976 save_area = gen_reg_rtx (save_mode);
977 emit_move_insn (save_area, stack_area);
980 return save_area;
983 return NULL_RTX;
986 static void
987 restore_fixed_argument_area (save_area, argblock, high_to_save, low_to_save)
988 rtx save_area;
989 rtx argblock;
990 int high_to_save;
991 int low_to_save;
993 enum machine_mode save_mode = GET_MODE (save_area);
994 int delta;
995 rtx stack_area;
997 #ifdef ARGS_GROW_DOWNWARD
998 delta = -high_to_save;
999 #else
1000 delta = low_to_save;
1001 #endif
1002 stack_area = gen_rtx_MEM (save_mode,
1003 memory_address (save_mode,
1004 plus_constant (argblock, delta)));
1005 set_mem_align (stack_area, PARM_BOUNDARY);
1007 if (save_mode != BLKmode)
1008 emit_move_insn (stack_area, save_area);
1009 else
1010 emit_block_move (stack_area, validize_mem (save_area),
1011 GEN_INT (high_to_save - low_to_save + 1),
1012 BLOCK_OP_CALL_PARM);
1014 #endif /* REG_PARM_STACK_SPACE */
1016 /* If any elements in ARGS refer to parameters that are to be passed in
1017 registers, but not in memory, and whose alignment does not permit a
1018 direct copy into registers. Copy the values into a group of pseudos
1019 which we will later copy into the appropriate hard registers.
1021 Pseudos for each unaligned argument will be stored into the array
1022 args[argnum].aligned_regs. The caller is responsible for deallocating
1023 the aligned_regs array if it is nonzero. */
1025 static void
1026 store_unaligned_arguments_into_pseudos (args, num_actuals)
1027 struct arg_data *args;
1028 int num_actuals;
1030 int i, j;
1032 for (i = 0; i < num_actuals; i++)
1033 if (args[i].reg != 0 && ! args[i].pass_on_stack
1034 && args[i].mode == BLKmode
1035 && (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
1036 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1038 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1039 int big_endian_correction = 0;
1041 args[i].n_aligned_regs
1042 = args[i].partial ? args[i].partial
1043 : (bytes + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
1045 args[i].aligned_regs = (rtx *) xmalloc (sizeof (rtx)
1046 * args[i].n_aligned_regs);
1048 /* Structures smaller than a word are aligned to the least
1049 significant byte (to the right). On a BYTES_BIG_ENDIAN machine,
1050 this means we must skip the empty high order bytes when
1051 calculating the bit offset. */
1052 if (BYTES_BIG_ENDIAN
1053 && bytes < UNITS_PER_WORD)
1054 big_endian_correction = (BITS_PER_WORD - (bytes * BITS_PER_UNIT));
1056 for (j = 0; j < args[i].n_aligned_regs; j++)
1058 rtx reg = gen_reg_rtx (word_mode);
1059 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1060 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
1062 args[i].aligned_regs[j] = reg;
1064 /* There is no need to restrict this code to loading items
1065 in TYPE_ALIGN sized hunks. The bitfield instructions can
1066 load up entire word sized registers efficiently.
1068 ??? This may not be needed anymore.
1069 We use to emit a clobber here but that doesn't let later
1070 passes optimize the instructions we emit. By storing 0 into
1071 the register later passes know the first AND to zero out the
1072 bitfield being set in the register is unnecessary. The store
1073 of 0 will be deleted as will at least the first AND. */
1075 emit_move_insn (reg, const0_rtx);
1077 bytes -= bitsize / BITS_PER_UNIT;
1078 store_bit_field (reg, bitsize, big_endian_correction, word_mode,
1079 extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
1080 word_mode, word_mode,
1081 BITS_PER_WORD),
1082 BITS_PER_WORD);
1087 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1088 ACTPARMS.
1090 NUM_ACTUALS is the total number of parameters.
1092 N_NAMED_ARGS is the total number of named arguments.
1094 FNDECL is the tree code for the target of this call (if known)
1096 ARGS_SO_FAR holds state needed by the target to know where to place
1097 the next argument.
1099 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1100 for arguments which are passed in registers.
1102 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1103 and may be modified by this routine.
1105 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1106 flags which may may be modified by this routine. */
1108 static void
1109 initialize_argument_information (num_actuals, args, args_size, n_named_args,
1110 actparms, fndecl, args_so_far,
1111 reg_parm_stack_space, old_stack_level,
1112 old_pending_adj, must_preallocate,
1113 ecf_flags)
1114 int num_actuals ATTRIBUTE_UNUSED;
1115 struct arg_data *args;
1116 struct args_size *args_size;
1117 int n_named_args ATTRIBUTE_UNUSED;
1118 tree actparms;
1119 tree fndecl;
1120 CUMULATIVE_ARGS *args_so_far;
1121 int reg_parm_stack_space;
1122 rtx *old_stack_level;
1123 int *old_pending_adj;
1124 int *must_preallocate;
1125 int *ecf_flags;
1127 /* 1 if scanning parms front to back, -1 if scanning back to front. */
1128 int inc;
1130 /* Count arg position in order args appear. */
1131 int argpos;
1133 struct args_size alignment_pad;
1134 int i;
1135 tree p;
1137 args_size->constant = 0;
1138 args_size->var = 0;
1140 /* In this loop, we consider args in the order they are written.
1141 We fill up ARGS from the front or from the back if necessary
1142 so that in any case the first arg to be pushed ends up at the front. */
1144 if (PUSH_ARGS_REVERSED)
1146 i = num_actuals - 1, inc = -1;
1147 /* In this case, must reverse order of args
1148 so that we compute and push the last arg first. */
1150 else
1152 i = 0, inc = 1;
1155 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1156 for (p = actparms, argpos = 0; p; p = TREE_CHAIN (p), i += inc, argpos++)
1158 tree type = TREE_TYPE (TREE_VALUE (p));
1159 int unsignedp;
1160 enum machine_mode mode;
1162 args[i].tree_value = TREE_VALUE (p);
1164 /* Replace erroneous argument with constant zero. */
1165 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1166 args[i].tree_value = integer_zero_node, type = integer_type_node;
1168 /* If TYPE is a transparent union, pass things the way we would
1169 pass the first field of the union. We have already verified that
1170 the modes are the same. */
1171 if (TREE_CODE (type) == UNION_TYPE && TYPE_TRANSPARENT_UNION (type))
1172 type = TREE_TYPE (TYPE_FIELDS (type));
1174 /* Decide where to pass this arg.
1176 args[i].reg is nonzero if all or part is passed in registers.
1178 args[i].partial is nonzero if part but not all is passed in registers,
1179 and the exact value says how many words are passed in registers.
1181 args[i].pass_on_stack is nonzero if the argument must at least be
1182 computed on the stack. It may then be loaded back into registers
1183 if args[i].reg is nonzero.
1185 These decisions are driven by the FUNCTION_... macros and must agree
1186 with those made by function.c. */
1188 /* See if this argument should be passed by invisible reference. */
1189 if ((TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1190 && contains_placeholder_p (TYPE_SIZE (type)))
1191 || TREE_ADDRESSABLE (type)
1192 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1193 || FUNCTION_ARG_PASS_BY_REFERENCE (*args_so_far, TYPE_MODE (type),
1194 type, argpos < n_named_args)
1195 #endif
1198 /* If we're compiling a thunk, pass through invisible
1199 references instead of making a copy. */
1200 if (current_function_is_thunk
1201 #ifdef FUNCTION_ARG_CALLEE_COPIES
1202 || (FUNCTION_ARG_CALLEE_COPIES (*args_so_far, TYPE_MODE (type),
1203 type, argpos < n_named_args)
1204 /* If it's in a register, we must make a copy of it too. */
1205 /* ??? Is this a sufficient test? Is there a better one? */
1206 && !(TREE_CODE (args[i].tree_value) == VAR_DECL
1207 && REG_P (DECL_RTL (args[i].tree_value)))
1208 && ! TREE_ADDRESSABLE (type))
1209 #endif
1212 /* C++ uses a TARGET_EXPR to indicate that we want to make a
1213 new object from the argument. If we are passing by
1214 invisible reference, the callee will do that for us, so we
1215 can strip off the TARGET_EXPR. This is not always safe,
1216 but it is safe in the only case where this is a useful
1217 optimization; namely, when the argument is a plain object.
1218 In that case, the frontend is just asking the backend to
1219 make a bitwise copy of the argument. */
1221 if (TREE_CODE (args[i].tree_value) == TARGET_EXPR
1222 && (DECL_P (TREE_OPERAND (args[i].tree_value, 1)))
1223 && ! REG_P (DECL_RTL (TREE_OPERAND (args[i].tree_value, 1))))
1224 args[i].tree_value = TREE_OPERAND (args[i].tree_value, 1);
1226 args[i].tree_value = build1 (ADDR_EXPR,
1227 build_pointer_type (type),
1228 args[i].tree_value);
1229 type = build_pointer_type (type);
1231 else if (TREE_CODE (args[i].tree_value) == TARGET_EXPR)
1233 /* In the V3 C++ ABI, parameters are destroyed in the caller.
1234 We implement this by passing the address of the temporary
1235 rather than expanding it into another allocated slot. */
1236 args[i].tree_value = build1 (ADDR_EXPR,
1237 build_pointer_type (type),
1238 args[i].tree_value);
1239 type = build_pointer_type (type);
1241 else
1243 /* We make a copy of the object and pass the address to the
1244 function being called. */
1245 rtx copy;
1247 if (!COMPLETE_TYPE_P (type)
1248 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1249 || (flag_stack_check && ! STACK_CHECK_BUILTIN
1250 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type),
1251 STACK_CHECK_MAX_VAR_SIZE))))
1253 /* This is a variable-sized object. Make space on the stack
1254 for it. */
1255 rtx size_rtx = expr_size (TREE_VALUE (p));
1257 if (*old_stack_level == 0)
1259 emit_stack_save (SAVE_BLOCK, old_stack_level, NULL_RTX);
1260 *old_pending_adj = pending_stack_adjust;
1261 pending_stack_adjust = 0;
1264 copy = gen_rtx_MEM (BLKmode,
1265 allocate_dynamic_stack_space
1266 (size_rtx, NULL_RTX, TYPE_ALIGN (type)));
1267 set_mem_attributes (copy, type, 1);
1269 else
1270 copy = assign_temp (type, 0, 1, 0);
1272 store_expr (args[i].tree_value, copy, 0);
1273 *ecf_flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
1275 args[i].tree_value = build1 (ADDR_EXPR,
1276 build_pointer_type (type),
1277 make_tree (type, copy));
1278 type = build_pointer_type (type);
1282 mode = TYPE_MODE (type);
1283 unsignedp = TREE_UNSIGNED (type);
1285 #ifdef PROMOTE_FUNCTION_ARGS
1286 mode = promote_mode (type, mode, &unsignedp, 1);
1287 #endif
1289 args[i].unsignedp = unsignedp;
1290 args[i].mode = mode;
1292 args[i].reg = FUNCTION_ARG (*args_so_far, mode, type,
1293 argpos < n_named_args);
1294 #ifdef FUNCTION_INCOMING_ARG
1295 /* If this is a sibling call and the machine has register windows, the
1296 register window has to be unwinded before calling the routine, so
1297 arguments have to go into the incoming registers. */
1298 args[i].tail_call_reg = FUNCTION_INCOMING_ARG (*args_so_far, mode, type,
1299 argpos < n_named_args);
1300 #else
1301 args[i].tail_call_reg = args[i].reg;
1302 #endif
1304 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1305 if (args[i].reg)
1306 args[i].partial
1307 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far, mode, type,
1308 argpos < n_named_args);
1309 #endif
1311 args[i].pass_on_stack = MUST_PASS_IN_STACK (mode, type);
1313 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1314 it means that we are to pass this arg in the register(s) designated
1315 by the PARALLEL, but also to pass it in the stack. */
1316 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1317 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1318 args[i].pass_on_stack = 1;
1320 /* If this is an addressable type, we must preallocate the stack
1321 since we must evaluate the object into its final location.
1323 If this is to be passed in both registers and the stack, it is simpler
1324 to preallocate. */
1325 if (TREE_ADDRESSABLE (type)
1326 || (args[i].pass_on_stack && args[i].reg != 0))
1327 *must_preallocate = 1;
1329 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1330 we cannot consider this function call constant. */
1331 if (TREE_ADDRESSABLE (type))
1332 *ecf_flags &= ~ECF_LIBCALL_BLOCK;
1334 /* Compute the stack-size of this argument. */
1335 if (args[i].reg == 0 || args[i].partial != 0
1336 || reg_parm_stack_space > 0
1337 || args[i].pass_on_stack)
1338 locate_and_pad_parm (mode, type,
1339 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1341 #else
1342 args[i].reg != 0,
1343 #endif
1344 fndecl, args_size, &args[i].offset,
1345 &args[i].size, &alignment_pad);
1347 #ifndef ARGS_GROW_DOWNWARD
1348 args[i].slot_offset = *args_size;
1349 #endif
1351 args[i].alignment_pad = alignment_pad;
1353 /* If a part of the arg was put into registers,
1354 don't include that part in the amount pushed. */
1355 if (reg_parm_stack_space == 0 && ! args[i].pass_on_stack)
1356 args[i].size.constant -= ((args[i].partial * UNITS_PER_WORD)
1357 / (PARM_BOUNDARY / BITS_PER_UNIT)
1358 * (PARM_BOUNDARY / BITS_PER_UNIT));
1360 /* Update ARGS_SIZE, the total stack space for args so far. */
1362 args_size->constant += args[i].size.constant;
1363 if (args[i].size.var)
1365 ADD_PARM_SIZE (*args_size, args[i].size.var);
1368 /* Since the slot offset points to the bottom of the slot,
1369 we must record it after incrementing if the args grow down. */
1370 #ifdef ARGS_GROW_DOWNWARD
1371 args[i].slot_offset = *args_size;
1373 args[i].slot_offset.constant = -args_size->constant;
1374 if (args_size->var)
1375 SUB_PARM_SIZE (args[i].slot_offset, args_size->var);
1376 #endif
1378 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1379 have been used, etc. */
1381 FUNCTION_ARG_ADVANCE (*args_so_far, TYPE_MODE (type), type,
1382 argpos < n_named_args);
1386 /* Update ARGS_SIZE to contain the total size for the argument block.
1387 Return the original constant component of the argument block's size.
1389 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1390 for arguments passed in registers. */
1392 static int
1393 compute_argument_block_size (reg_parm_stack_space, args_size,
1394 preferred_stack_boundary)
1395 int reg_parm_stack_space;
1396 struct args_size *args_size;
1397 int preferred_stack_boundary ATTRIBUTE_UNUSED;
1399 int unadjusted_args_size = args_size->constant;
1401 /* For accumulate outgoing args mode we don't need to align, since the frame
1402 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1403 backends from generating misaligned frame sizes. */
1404 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1405 preferred_stack_boundary = STACK_BOUNDARY;
1407 /* Compute the actual size of the argument block required. The variable
1408 and constant sizes must be combined, the size may have to be rounded,
1409 and there may be a minimum required size. */
1411 if (args_size->var)
1413 args_size->var = ARGS_SIZE_TREE (*args_size);
1414 args_size->constant = 0;
1416 preferred_stack_boundary /= BITS_PER_UNIT;
1417 if (preferred_stack_boundary > 1)
1419 /* We don't handle this case yet. To handle it correctly we have
1420 to add the delta, round and subtract the delta.
1421 Currently no machine description requires this support. */
1422 if (stack_pointer_delta & (preferred_stack_boundary - 1))
1423 abort ();
1424 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1427 if (reg_parm_stack_space > 0)
1429 args_size->var
1430 = size_binop (MAX_EXPR, args_size->var,
1431 ssize_int (reg_parm_stack_space));
1433 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1434 /* The area corresponding to register parameters is not to count in
1435 the size of the block we need. So make the adjustment. */
1436 args_size->var
1437 = size_binop (MINUS_EXPR, args_size->var,
1438 ssize_int (reg_parm_stack_space));
1439 #endif
1442 else
1444 preferred_stack_boundary /= BITS_PER_UNIT;
1445 if (preferred_stack_boundary < 1)
1446 preferred_stack_boundary = 1;
1447 args_size->constant = (((args_size->constant
1448 + stack_pointer_delta
1449 + preferred_stack_boundary - 1)
1450 / preferred_stack_boundary
1451 * preferred_stack_boundary)
1452 - stack_pointer_delta);
1454 args_size->constant = MAX (args_size->constant,
1455 reg_parm_stack_space);
1457 #ifdef MAYBE_REG_PARM_STACK_SPACE
1458 if (reg_parm_stack_space == 0)
1459 args_size->constant = 0;
1460 #endif
1462 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1463 args_size->constant -= reg_parm_stack_space;
1464 #endif
1466 return unadjusted_args_size;
1469 /* Precompute parameters as needed for a function call.
1471 FLAGS is mask of ECF_* constants.
1473 NUM_ACTUALS is the number of arguments.
1475 ARGS is an array containing information for each argument; this
1476 routine fills in the INITIAL_VALUE and VALUE fields for each
1477 precomputed argument. */
1479 static void
1480 precompute_arguments (flags, num_actuals, args)
1481 int flags;
1482 int num_actuals;
1483 struct arg_data *args;
1485 int i;
1487 /* If this function call is cse'able, precompute all the parameters.
1488 Note that if the parameter is constructed into a temporary, this will
1489 cause an additional copy because the parameter will be constructed
1490 into a temporary location and then copied into the outgoing arguments.
1491 If a parameter contains a call to alloca and this function uses the
1492 stack, precompute the parameter. */
1494 /* If we preallocated the stack space, and some arguments must be passed
1495 on the stack, then we must precompute any parameter which contains a
1496 function call which will store arguments on the stack.
1497 Otherwise, evaluating the parameter may clobber previous parameters
1498 which have already been stored into the stack. (we have code to avoid
1499 such case by saving the outgoing stack arguments, but it results in
1500 worse code) */
1502 for (i = 0; i < num_actuals; i++)
1503 if ((flags & ECF_LIBCALL_BLOCK)
1504 || calls_function (args[i].tree_value, !ACCUMULATE_OUTGOING_ARGS))
1506 enum machine_mode mode;
1508 /* If this is an addressable type, we cannot pre-evaluate it. */
1509 if (TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value)))
1510 abort ();
1512 args[i].value
1513 = expand_expr (args[i].tree_value, NULL_RTX, VOIDmode, 0);
1515 /* ANSI doesn't require a sequence point here,
1516 but PCC has one, so this will avoid some problems. */
1517 emit_queue ();
1519 args[i].initial_value = args[i].value
1520 = protect_from_queue (args[i].value, 0);
1522 mode = TYPE_MODE (TREE_TYPE (args[i].tree_value));
1523 if (mode != args[i].mode)
1525 args[i].value
1526 = convert_modes (args[i].mode, mode,
1527 args[i].value, args[i].unsignedp);
1528 #ifdef PROMOTE_FOR_CALL_ONLY
1529 /* CSE will replace this only if it contains args[i].value
1530 pseudo, so convert it down to the declared mode using
1531 a SUBREG. */
1532 if (GET_CODE (args[i].value) == REG
1533 && GET_MODE_CLASS (args[i].mode) == MODE_INT)
1535 args[i].initial_value
1536 = gen_lowpart_SUBREG (mode, args[i].value);
1537 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
1538 SUBREG_PROMOTED_UNSIGNED_SET (args[i].initial_value,
1539 args[i].unsignedp);
1541 #endif
1546 /* Given the current state of MUST_PREALLOCATE and information about
1547 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1548 compute and return the final value for MUST_PREALLOCATE. */
1550 static int
1551 finalize_must_preallocate (must_preallocate, num_actuals, args, args_size)
1552 int must_preallocate;
1553 int num_actuals;
1554 struct arg_data *args;
1555 struct args_size *args_size;
1557 /* See if we have or want to preallocate stack space.
1559 If we would have to push a partially-in-regs parm
1560 before other stack parms, preallocate stack space instead.
1562 If the size of some parm is not a multiple of the required stack
1563 alignment, we must preallocate.
1565 If the total size of arguments that would otherwise create a copy in
1566 a temporary (such as a CALL) is more than half the total argument list
1567 size, preallocation is faster.
1569 Another reason to preallocate is if we have a machine (like the m88k)
1570 where stack alignment is required to be maintained between every
1571 pair of insns, not just when the call is made. However, we assume here
1572 that such machines either do not have push insns (and hence preallocation
1573 would occur anyway) or the problem is taken care of with
1574 PUSH_ROUNDING. */
1576 if (! must_preallocate)
1578 int partial_seen = 0;
1579 int copy_to_evaluate_size = 0;
1580 int i;
1582 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1584 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1585 partial_seen = 1;
1586 else if (partial_seen && args[i].reg == 0)
1587 must_preallocate = 1;
1589 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1590 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1591 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1592 || TREE_CODE (args[i].tree_value) == COND_EXPR
1593 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1594 copy_to_evaluate_size
1595 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1598 if (copy_to_evaluate_size * 2 >= args_size->constant
1599 && args_size->constant > 0)
1600 must_preallocate = 1;
1602 return must_preallocate;
1605 /* If we preallocated stack space, compute the address of each argument
1606 and store it into the ARGS array.
1608 We need not ensure it is a valid memory address here; it will be
1609 validized when it is used.
1611 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1613 static void
1614 compute_argument_addresses (args, argblock, num_actuals)
1615 struct arg_data *args;
1616 rtx argblock;
1617 int num_actuals;
1619 if (argblock)
1621 rtx arg_reg = argblock;
1622 int i, arg_offset = 0;
1624 if (GET_CODE (argblock) == PLUS)
1625 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1627 for (i = 0; i < num_actuals; i++)
1629 rtx offset = ARGS_SIZE_RTX (args[i].offset);
1630 rtx slot_offset = ARGS_SIZE_RTX (args[i].slot_offset);
1631 rtx addr;
1633 /* Skip this parm if it will not be passed on the stack. */
1634 if (! args[i].pass_on_stack && args[i].reg != 0)
1635 continue;
1637 if (GET_CODE (offset) == CONST_INT)
1638 addr = plus_constant (arg_reg, INTVAL (offset));
1639 else
1640 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1642 addr = plus_constant (addr, arg_offset);
1643 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1644 set_mem_align (args[i].stack, PARM_BOUNDARY);
1645 set_mem_attributes (args[i].stack,
1646 TREE_TYPE (args[i].tree_value), 1);
1648 if (GET_CODE (slot_offset) == CONST_INT)
1649 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1650 else
1651 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1653 addr = plus_constant (addr, arg_offset);
1654 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1655 set_mem_align (args[i].stack_slot, PARM_BOUNDARY);
1656 set_mem_attributes (args[i].stack_slot,
1657 TREE_TYPE (args[i].tree_value), 1);
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);
1669 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1670 in a call instruction.
1672 FNDECL is the tree node for the target function. For an indirect call
1673 FNDECL will be NULL_TREE.
1675 ADDR is the operand 0 of CALL_EXPR for this call. */
1677 static rtx
1678 rtx_for_function_call (fndecl, addr)
1679 tree fndecl;
1680 tree addr;
1682 rtx funexp;
1684 /* Get the function to call, in the form of RTL. */
1685 if (fndecl)
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))
1691 assemble_external (fndecl);
1692 TREE_USED (fndecl) = 1;
1695 /* Get a SYMBOL_REF rtx for the function address. */
1696 funexp = XEXP (DECL_RTL (fndecl), 0);
1698 else
1699 /* Generate an rtx (probably a pseudo-register) for the address. */
1701 push_temp_slots ();
1702 funexp = expand_expr (addr, NULL_RTX, VOIDmode, 0);
1703 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1704 emit_queue ();
1706 return funexp;
1709 /* Do the register loads required for any wholly-register parms or any
1710 parms which are passed both on the stack and in a register. Their
1711 expressions were already evaluated.
1713 Mark all register-parms as living through the call, putting these USE
1714 insns in the CALL_INSN_FUNCTION_USAGE field.
1716 When IS_SIBCALL, perform the check_sibcall_overlap_argument_overlap
1717 checking, setting *SIBCALL_FAILURE if appropriate. */
1719 static void
1720 load_register_parameters (args, num_actuals, call_fusage, flags,
1721 is_sibcall, sibcall_failure)
1722 struct arg_data *args;
1723 int num_actuals;
1724 rtx *call_fusage;
1725 int flags;
1726 int is_sibcall;
1727 int *sibcall_failure;
1729 int i, j;
1731 #ifdef LOAD_ARGS_REVERSED
1732 for (i = num_actuals - 1; i >= 0; i--)
1733 #else
1734 for (i = 0; i < num_actuals; i++)
1735 #endif
1737 rtx reg = ((flags & ECF_SIBCALL)
1738 ? args[i].tail_call_reg : args[i].reg);
1739 int partial = args[i].partial;
1740 int nregs;
1742 if (reg)
1744 rtx before_arg = get_last_insn ();
1745 /* Set to non-negative if must move a word at a time, even if just
1746 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1747 we just use a normal move insn. This value can be zero if the
1748 argument is a zero size structure with no fields. */
1749 nregs = (partial ? partial
1750 : (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1751 ? ((int_size_in_bytes (TREE_TYPE (args[i].tree_value))
1752 + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)
1753 : -1));
1755 /* Handle calls that pass values in multiple non-contiguous
1756 locations. The Irix 6 ABI has examples of this. */
1758 if (GET_CODE (reg) == PARALLEL)
1759 emit_group_load (reg, args[i].value,
1760 int_size_in_bytes (TREE_TYPE (args[i].tree_value)));
1762 /* If simple case, just do move. If normal partial, store_one_arg
1763 has already loaded the register for us. In all other cases,
1764 load the register(s) from memory. */
1766 else if (nregs == -1)
1767 emit_move_insn (reg, args[i].value);
1769 /* If we have pre-computed the values to put in the registers in
1770 the case of non-aligned structures, copy them in now. */
1772 else if (args[i].n_aligned_regs != 0)
1773 for (j = 0; j < args[i].n_aligned_regs; j++)
1774 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
1775 args[i].aligned_regs[j]);
1777 else if (partial == 0 || args[i].pass_on_stack)
1778 move_block_to_reg (REGNO (reg),
1779 validize_mem (args[i].value), nregs,
1780 args[i].mode);
1782 /* When a parameter is a block, and perhaps in other cases, it is
1783 possible that it did a load from an argument slot that was
1784 already clobbered. */
1785 if (is_sibcall
1786 && check_sibcall_argument_overlap (before_arg, &args[i], 0))
1787 *sibcall_failure = 1;
1789 /* Handle calls that pass values in multiple non-contiguous
1790 locations. The Irix 6 ABI has examples of this. */
1791 if (GET_CODE (reg) == PARALLEL)
1792 use_group_regs (call_fusage, reg);
1793 else if (nregs == -1)
1794 use_reg (call_fusage, reg);
1795 else
1796 use_regs (call_fusage, REGNO (reg), nregs == 0 ? 1 : nregs);
1801 /* Try to integrate function. See expand_inline_function for documentation
1802 about the parameters. */
1804 static rtx
1805 try_to_integrate (fndecl, actparms, target, ignore, type, structure_value_addr)
1806 tree fndecl;
1807 tree actparms;
1808 rtx target;
1809 int ignore;
1810 tree type;
1811 rtx structure_value_addr;
1813 rtx temp;
1814 rtx before_call;
1815 int i;
1816 rtx old_stack_level = 0;
1817 int reg_parm_stack_space = 0;
1819 #ifdef REG_PARM_STACK_SPACE
1820 #ifdef MAYBE_REG_PARM_STACK_SPACE
1821 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
1822 #else
1823 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
1824 #endif
1825 #endif
1827 before_call = get_last_insn ();
1829 timevar_push (TV_INTEGRATION);
1831 temp = expand_inline_function (fndecl, actparms, target,
1832 ignore, type,
1833 structure_value_addr);
1835 timevar_pop (TV_INTEGRATION);
1837 /* If inlining succeeded, return. */
1838 if (temp != (rtx) (size_t) - 1)
1840 if (ACCUMULATE_OUTGOING_ARGS)
1842 /* If the outgoing argument list must be preserved, push
1843 the stack before executing the inlined function if it
1844 makes any calls. */
1846 i = reg_parm_stack_space;
1847 if (i > highest_outgoing_arg_in_use)
1848 i = highest_outgoing_arg_in_use;
1849 while (--i >= 0 && stack_usage_map[i] == 0)
1852 if (stack_arg_under_construction || i >= 0)
1854 rtx first_insn
1855 = before_call ? NEXT_INSN (before_call) : get_insns ();
1856 rtx insn = NULL_RTX, seq;
1858 /* Look for a call in the inline function code.
1859 If DECL_SAVED_INSNS (fndecl)->outgoing_args_size is
1860 nonzero then there is a call and it is not necessary
1861 to scan the insns. */
1863 if (DECL_SAVED_INSNS (fndecl)->outgoing_args_size == 0)
1864 for (insn = first_insn; insn; insn = NEXT_INSN (insn))
1865 if (GET_CODE (insn) == CALL_INSN)
1866 break;
1868 if (insn)
1870 /* Reserve enough stack space so that the largest
1871 argument list of any function call in the inline
1872 function does not overlap the argument list being
1873 evaluated. This is usually an overestimate because
1874 allocate_dynamic_stack_space reserves space for an
1875 outgoing argument list in addition to the requested
1876 space, but there is no way to ask for stack space such
1877 that an argument list of a certain length can be
1878 safely constructed.
1880 Add the stack space reserved for register arguments, if
1881 any, in the inline function. What is really needed is the
1882 largest value of reg_parm_stack_space in the inline
1883 function, but that is not available. Using the current
1884 value of reg_parm_stack_space is wrong, but gives
1885 correct results on all supported machines. */
1887 int adjust = (DECL_SAVED_INSNS (fndecl)->outgoing_args_size
1888 + reg_parm_stack_space);
1890 start_sequence ();
1891 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1892 allocate_dynamic_stack_space (GEN_INT (adjust),
1893 NULL_RTX, BITS_PER_UNIT);
1894 seq = get_insns ();
1895 end_sequence ();
1896 emit_insn_before (seq, first_insn);
1897 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
1902 /* If the result is equivalent to TARGET, return TARGET to simplify
1903 checks in store_expr. They can be equivalent but not equal in the
1904 case of a function that returns BLKmode. */
1905 if (temp != target && rtx_equal_p (temp, target))
1906 return target;
1907 return temp;
1910 /* If inlining failed, mark FNDECL as needing to be compiled
1911 separately after all. If function was declared inline,
1912 give a warning. */
1913 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
1914 && optimize > 0 && !TREE_ADDRESSABLE (fndecl))
1916 warning_with_decl (fndecl, "inlining failed in call to `%s'");
1917 warning ("called from here");
1919 (*lang_hooks.mark_addressable) (fndecl);
1920 return (rtx) (size_t) - 1;
1923 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1924 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1925 bytes, then we would need to push some additional bytes to pad the
1926 arguments. So, we compute an adjust to the stack pointer for an
1927 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1928 bytes. Then, when the arguments are pushed the stack will be perfectly
1929 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1930 be popped after the call. Returns the adjustment. */
1932 static int
1933 combine_pending_stack_adjustment_and_call (unadjusted_args_size,
1934 args_size,
1935 preferred_unit_stack_boundary)
1936 int unadjusted_args_size;
1937 struct args_size *args_size;
1938 int preferred_unit_stack_boundary;
1940 /* The number of bytes to pop so that the stack will be
1941 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1942 HOST_WIDE_INT adjustment;
1943 /* The alignment of the stack after the arguments are pushed, if we
1944 just pushed the arguments without adjust the stack here. */
1945 HOST_WIDE_INT unadjusted_alignment;
1947 unadjusted_alignment
1948 = ((stack_pointer_delta + unadjusted_args_size)
1949 % preferred_unit_stack_boundary);
1951 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1952 as possible -- leaving just enough left to cancel out the
1953 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1954 PENDING_STACK_ADJUST is non-negative, and congruent to
1955 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1957 /* Begin by trying to pop all the bytes. */
1958 unadjusted_alignment
1959 = (unadjusted_alignment
1960 - (pending_stack_adjust % preferred_unit_stack_boundary));
1961 adjustment = pending_stack_adjust;
1962 /* Push enough additional bytes that the stack will be aligned
1963 after the arguments are pushed. */
1964 if (preferred_unit_stack_boundary > 1)
1966 if (unadjusted_alignment > 0)
1967 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
1968 else
1969 adjustment += unadjusted_alignment;
1972 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1973 bytes after the call. The right number is the entire
1974 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1975 by the arguments in the first place. */
1976 args_size->constant
1977 = pending_stack_adjust - adjustment + unadjusted_args_size;
1979 return adjustment;
1982 /* Scan X expression if it does not dereference any argument slots
1983 we already clobbered by tail call arguments (as noted in stored_args_map
1984 bitmap).
1985 Return nonzero if X expression dereferences such argument slots,
1986 zero otherwise. */
1988 static int
1989 check_sibcall_argument_overlap_1 (x)
1990 rtx x;
1992 RTX_CODE code;
1993 int i, j;
1994 unsigned int k;
1995 const char *fmt;
1997 if (x == NULL_RTX)
1998 return 0;
2000 code = GET_CODE (x);
2002 if (code == MEM)
2004 if (XEXP (x, 0) == current_function_internal_arg_pointer)
2005 i = 0;
2006 else if (GET_CODE (XEXP (x, 0)) == PLUS
2007 && XEXP (XEXP (x, 0), 0) ==
2008 current_function_internal_arg_pointer
2009 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT)
2010 i = INTVAL (XEXP (XEXP (x, 0), 1));
2011 else
2012 return 0;
2014 #ifdef ARGS_GROW_DOWNWARD
2015 i = -i - GET_MODE_SIZE (GET_MODE (x));
2016 #endif
2018 for (k = 0; k < GET_MODE_SIZE (GET_MODE (x)); k++)
2019 if (i + k < stored_args_map->n_bits
2020 && TEST_BIT (stored_args_map, i + k))
2021 return 1;
2023 return 0;
2026 /* Scan all subexpressions. */
2027 fmt = GET_RTX_FORMAT (code);
2028 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
2030 if (*fmt == 'e')
2032 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
2033 return 1;
2035 else if (*fmt == 'E')
2037 for (j = 0; j < XVECLEN (x, i); j++)
2038 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
2039 return 1;
2042 return 0;
2045 /* Scan sequence after INSN if it does not dereference any argument slots
2046 we already clobbered by tail call arguments (as noted in stored_args_map
2047 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
2048 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
2049 should be 0). Return nonzero if sequence after INSN dereferences such argument
2050 slots, zero otherwise. */
2052 static int
2053 check_sibcall_argument_overlap (insn, arg, mark_stored_args_map)
2054 rtx insn;
2055 struct arg_data *arg;
2056 int mark_stored_args_map;
2058 int low, high;
2060 if (insn == NULL_RTX)
2061 insn = get_insns ();
2062 else
2063 insn = NEXT_INSN (insn);
2065 for (; insn; insn = NEXT_INSN (insn))
2066 if (INSN_P (insn)
2067 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
2068 break;
2070 if (mark_stored_args_map)
2072 #ifdef ARGS_GROW_DOWNWARD
2073 low = -arg->slot_offset.constant - arg->size.constant;
2074 #else
2075 low = arg->slot_offset.constant;
2076 #endif
2078 for (high = low + arg->size.constant; low < high; low++)
2079 SET_BIT (stored_args_map, low);
2081 return insn != NULL_RTX;
2084 static tree
2085 fix_unsafe_tree (t)
2086 tree t;
2088 switch (unsafe_for_reeval (t))
2090 case 0: /* Safe. */
2091 break;
2093 case 1: /* Mildly unsafe. */
2094 t = unsave_expr (t);
2095 break;
2097 case 2: /* Wildly unsafe. */
2099 tree var = build_decl (VAR_DECL, NULL_TREE,
2100 TREE_TYPE (t));
2101 SET_DECL_RTL (var,
2102 expand_expr (t, NULL_RTX, VOIDmode, EXPAND_NORMAL));
2103 t = var;
2105 break;
2107 default:
2108 abort ();
2110 return t;
2113 /* Generate all the code for a function call
2114 and return an rtx for its value.
2115 Store the value in TARGET (specified as an rtx) if convenient.
2116 If the value is stored in TARGET then TARGET is returned.
2117 If IGNORE is nonzero, then we ignore the value of the function call. */
2120 expand_call (exp, target, ignore)
2121 tree exp;
2122 rtx target;
2123 int ignore;
2125 /* Nonzero if we are currently expanding a call. */
2126 static int currently_expanding_call = 0;
2128 /* List of actual parameters. */
2129 tree actparms = TREE_OPERAND (exp, 1);
2130 /* RTX for the function to be called. */
2131 rtx funexp;
2132 /* Sequence of insns to perform a tail recursive "call". */
2133 rtx tail_recursion_insns = NULL_RTX;
2134 /* Sequence of insns to perform a normal "call". */
2135 rtx normal_call_insns = NULL_RTX;
2136 /* Sequence of insns to perform a tail recursive "call". */
2137 rtx tail_call_insns = NULL_RTX;
2138 /* Data type of the function. */
2139 tree funtype;
2140 /* Declaration of the function being called,
2141 or 0 if the function is computed (not known by name). */
2142 tree fndecl = 0;
2143 rtx insn;
2144 int try_tail_call = 1;
2145 int try_tail_recursion = 1;
2146 int pass;
2148 /* Register in which non-BLKmode value will be returned,
2149 or 0 if no value or if value is BLKmode. */
2150 rtx valreg;
2151 /* Address where we should return a BLKmode value;
2152 0 if value not BLKmode. */
2153 rtx structure_value_addr = 0;
2154 /* Nonzero if that address is being passed by treating it as
2155 an extra, implicit first parameter. Otherwise,
2156 it is passed by being copied directly into struct_value_rtx. */
2157 int structure_value_addr_parm = 0;
2158 /* Size of aggregate value wanted, or zero if none wanted
2159 or if we are using the non-reentrant PCC calling convention
2160 or expecting the value in registers. */
2161 HOST_WIDE_INT struct_value_size = 0;
2162 /* Nonzero if called function returns an aggregate in memory PCC style,
2163 by returning the address of where to find it. */
2164 int pcc_struct_value = 0;
2166 /* Number of actual parameters in this call, including struct value addr. */
2167 int num_actuals;
2168 /* Number of named args. Args after this are anonymous ones
2169 and they must all go on the stack. */
2170 int n_named_args;
2172 /* Vector of information about each argument.
2173 Arguments are numbered in the order they will be pushed,
2174 not the order they are written. */
2175 struct arg_data *args;
2177 /* Total size in bytes of all the stack-parms scanned so far. */
2178 struct args_size args_size;
2179 struct args_size adjusted_args_size;
2180 /* Size of arguments before any adjustments (such as rounding). */
2181 int unadjusted_args_size;
2182 /* Data on reg parms scanned so far. */
2183 CUMULATIVE_ARGS args_so_far;
2184 /* Nonzero if a reg parm has been scanned. */
2185 int reg_parm_seen;
2186 /* Nonzero if this is an indirect function call. */
2188 /* Nonzero if we must avoid push-insns in the args for this call.
2189 If stack space is allocated for register parameters, but not by the
2190 caller, then it is preallocated in the fixed part of the stack frame.
2191 So the entire argument block must then be preallocated (i.e., we
2192 ignore PUSH_ROUNDING in that case). */
2194 int must_preallocate = !PUSH_ARGS;
2196 /* Size of the stack reserved for parameter registers. */
2197 int reg_parm_stack_space = 0;
2199 /* Address of space preallocated for stack parms
2200 (on machines that lack push insns), or 0 if space not preallocated. */
2201 rtx argblock = 0;
2203 /* Mask of ECF_ flags. */
2204 int flags = 0;
2205 /* Nonzero if this is a call to an inline function. */
2206 int is_integrable = 0;
2207 #ifdef REG_PARM_STACK_SPACE
2208 /* Define the boundary of the register parm stack space that needs to be
2209 saved, if any. */
2210 int low_to_save, high_to_save;
2211 rtx save_area = 0; /* Place that it is saved */
2212 #endif
2214 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
2215 char *initial_stack_usage_map = stack_usage_map;
2216 int old_stack_arg_under_construction = 0;
2218 rtx old_stack_level = 0;
2219 int old_pending_adj = 0;
2220 int old_inhibit_defer_pop = inhibit_defer_pop;
2221 int old_stack_allocated;
2222 rtx call_fusage;
2223 tree p = TREE_OPERAND (exp, 0);
2224 tree addr = TREE_OPERAND (exp, 0);
2225 int i;
2226 /* The alignment of the stack, in bits. */
2227 HOST_WIDE_INT preferred_stack_boundary;
2228 /* The alignment of the stack, in bytes. */
2229 HOST_WIDE_INT preferred_unit_stack_boundary;
2231 /* See if this is "nothrow" function call. */
2232 if (TREE_NOTHROW (exp))
2233 flags |= ECF_NOTHROW;
2235 /* See if we can find a DECL-node for the actual function.
2236 As a result, decide whether this is a call to an integrable function. */
2238 fndecl = get_callee_fndecl (exp);
2239 if (fndecl)
2241 if (!flag_no_inline
2242 && fndecl != current_function_decl
2243 && DECL_INLINE (fndecl)
2244 && DECL_SAVED_INSNS (fndecl)
2245 && DECL_SAVED_INSNS (fndecl)->inlinable)
2246 is_integrable = 1;
2247 else if (! TREE_ADDRESSABLE (fndecl))
2249 /* In case this function later becomes inlinable,
2250 record that there was already a non-inline call to it.
2252 Use abstraction instead of setting TREE_ADDRESSABLE
2253 directly. */
2254 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
2255 && optimize > 0)
2257 warning_with_decl (fndecl, "can't inline call to `%s'");
2258 warning ("called from here");
2260 (*lang_hooks.mark_addressable) (fndecl);
2263 flags |= flags_from_decl_or_type (fndecl);
2266 /* If we don't have specific function to call, see if we have a
2267 attributes set in the type. */
2268 else
2269 flags |= flags_from_decl_or_type (TREE_TYPE (TREE_TYPE (p)));
2271 #ifdef REG_PARM_STACK_SPACE
2272 #ifdef MAYBE_REG_PARM_STACK_SPACE
2273 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
2274 #else
2275 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
2276 #endif
2277 #endif
2279 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2280 if (reg_parm_stack_space > 0 && PUSH_ARGS)
2281 must_preallocate = 1;
2282 #endif
2284 /* Warn if this value is an aggregate type,
2285 regardless of which calling convention we are using for it. */
2286 if (warn_aggregate_return && AGGREGATE_TYPE_P (TREE_TYPE (exp)))
2287 warning ("function call has aggregate value");
2289 /* Set up a place to return a structure. */
2291 /* Cater to broken compilers. */
2292 if (aggregate_value_p (exp))
2294 /* This call returns a big structure. */
2295 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
2297 #ifdef PCC_STATIC_STRUCT_RETURN
2299 pcc_struct_value = 1;
2300 /* Easier than making that case work right. */
2301 if (is_integrable)
2303 /* In case this is a static function, note that it has been
2304 used. */
2305 if (! TREE_ADDRESSABLE (fndecl))
2306 (*lang_hooks.mark_addressable) (fndecl);
2307 is_integrable = 0;
2310 #else /* not PCC_STATIC_STRUCT_RETURN */
2312 struct_value_size = int_size_in_bytes (TREE_TYPE (exp));
2314 if (CALL_EXPR_HAS_RETURN_SLOT_ADDR (exp))
2316 /* The structure value address arg is already in actparms.
2317 Pull it out. It might be nice to just leave it there, but
2318 we need to set structure_value_addr. */
2319 tree return_arg = TREE_VALUE (actparms);
2320 actparms = TREE_CHAIN (actparms);
2321 structure_value_addr = expand_expr (return_arg, NULL_RTX,
2322 VOIDmode, EXPAND_NORMAL);
2324 else if (target && GET_CODE (target) == MEM)
2325 structure_value_addr = XEXP (target, 0);
2326 else
2328 /* For variable-sized objects, we must be called with a target
2329 specified. If we were to allocate space on the stack here,
2330 we would have no way of knowing when to free it. */
2331 rtx d = assign_temp (TREE_TYPE (exp), 1, 1, 1);
2333 mark_temp_addr_taken (d);
2334 structure_value_addr = XEXP (d, 0);
2335 target = 0;
2338 #endif /* not PCC_STATIC_STRUCT_RETURN */
2341 /* If called function is inline, try to integrate it. */
2343 if (is_integrable)
2345 rtx temp = try_to_integrate (fndecl, actparms, target,
2346 ignore, TREE_TYPE (exp),
2347 structure_value_addr);
2348 if (temp != (rtx) (size_t) - 1)
2349 return temp;
2352 /* Figure out the amount to which the stack should be aligned. */
2353 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
2354 if (fndecl)
2356 struct cgraph_rtl_info *i = cgraph_rtl_info (fndecl);
2357 if (i && i->preferred_incoming_stack_boundary)
2358 preferred_stack_boundary = i->preferred_incoming_stack_boundary;
2361 /* Operand 0 is a pointer-to-function; get the type of the function. */
2362 funtype = TREE_TYPE (addr);
2363 if (! POINTER_TYPE_P (funtype))
2364 abort ();
2365 funtype = TREE_TYPE (funtype);
2367 /* See if this is a call to a function that can return more than once
2368 or a call to longjmp or malloc. */
2369 flags |= special_function_p (fndecl, flags);
2371 if (flags & ECF_MAY_BE_ALLOCA)
2372 current_function_calls_alloca = 1;
2374 /* If struct_value_rtx is 0, it means pass the address
2375 as if it were an extra parameter. */
2376 if (structure_value_addr && struct_value_rtx == 0)
2378 /* If structure_value_addr is a REG other than
2379 virtual_outgoing_args_rtx, we can use always use it. If it
2380 is not a REG, we must always copy it into a register.
2381 If it is virtual_outgoing_args_rtx, we must copy it to another
2382 register in some cases. */
2383 rtx temp = (GET_CODE (structure_value_addr) != REG
2384 || (ACCUMULATE_OUTGOING_ARGS
2385 && stack_arg_under_construction
2386 && structure_value_addr == virtual_outgoing_args_rtx)
2387 ? copy_addr_to_reg (structure_value_addr)
2388 : structure_value_addr);
2390 actparms
2391 = tree_cons (error_mark_node,
2392 make_tree (build_pointer_type (TREE_TYPE (funtype)),
2393 temp),
2394 actparms);
2395 structure_value_addr_parm = 1;
2398 /* Count the arguments and set NUM_ACTUALS. */
2399 for (p = actparms, num_actuals = 0; p; p = TREE_CHAIN (p))
2400 num_actuals++;
2402 /* Compute number of named args.
2403 Normally, don't include the last named arg if anonymous args follow.
2404 We do include the last named arg if STRICT_ARGUMENT_NAMING is nonzero.
2405 (If no anonymous args follow, the result of list_length is actually
2406 one too large. This is harmless.)
2408 If PRETEND_OUTGOING_VARARGS_NAMED is set and STRICT_ARGUMENT_NAMING is
2409 zero, this machine will be able to place unnamed args that were
2410 passed in registers into the stack. So treat all args as named.
2411 This allows the insns emitting for a specific argument list to be
2412 independent of the function declaration.
2414 If PRETEND_OUTGOING_VARARGS_NAMED is not set, we do not have any
2415 reliable way to pass unnamed args in registers, so we must force
2416 them into memory. */
2418 if ((STRICT_ARGUMENT_NAMING
2419 || ! PRETEND_OUTGOING_VARARGS_NAMED)
2420 && TYPE_ARG_TYPES (funtype) != 0)
2421 n_named_args
2422 = (list_length (TYPE_ARG_TYPES (funtype))
2423 /* Don't include the last named arg. */
2424 - (STRICT_ARGUMENT_NAMING ? 0 : 1)
2425 /* Count the struct value address, if it is passed as a parm. */
2426 + structure_value_addr_parm);
2427 else
2428 /* If we know nothing, treat all args as named. */
2429 n_named_args = num_actuals;
2431 /* Start updating where the next arg would go.
2433 On some machines (such as the PA) indirect calls have a different
2434 calling convention than normal calls. The last argument in
2435 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2436 or not. */
2437 INIT_CUMULATIVE_ARGS (args_so_far, funtype, NULL_RTX, fndecl);
2439 /* Make a vector to hold all the information about each arg. */
2440 args = (struct arg_data *) alloca (num_actuals * sizeof (struct arg_data));
2441 memset ((char *) args, 0, num_actuals * sizeof (struct arg_data));
2443 /* Build up entries in the ARGS array, compute the size of the
2444 arguments into ARGS_SIZE, etc. */
2445 initialize_argument_information (num_actuals, args, &args_size,
2446 n_named_args, actparms, fndecl,
2447 &args_so_far, reg_parm_stack_space,
2448 &old_stack_level, &old_pending_adj,
2449 &must_preallocate, &flags);
2451 if (args_size.var)
2453 /* If this function requires a variable-sized argument list, don't
2454 try to make a cse'able block for this call. We may be able to
2455 do this eventually, but it is too complicated to keep track of
2456 what insns go in the cse'able block and which don't. */
2458 flags &= ~ECF_LIBCALL_BLOCK;
2459 must_preallocate = 1;
2462 /* Now make final decision about preallocating stack space. */
2463 must_preallocate = finalize_must_preallocate (must_preallocate,
2464 num_actuals, args,
2465 &args_size);
2467 /* If the structure value address will reference the stack pointer, we
2468 must stabilize it. We don't need to do this if we know that we are
2469 not going to adjust the stack pointer in processing this call. */
2471 if (structure_value_addr
2472 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2473 || reg_mentioned_p (virtual_outgoing_args_rtx,
2474 structure_value_addr))
2475 && (args_size.var
2476 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
2477 structure_value_addr = copy_to_reg (structure_value_addr);
2479 /* Tail calls can make things harder to debug, and we're traditionally
2480 pushed these optimizations into -O2. Don't try if we're already
2481 expanding a call, as that means we're an argument. Don't try if
2482 there's cleanups, as we know there's code to follow the call.
2484 If rtx_equal_function_value_matters is false, that means we've
2485 finished with regular parsing. Which means that some of the
2486 machinery we use to generate tail-calls is no longer in place.
2487 This is most often true of sjlj-exceptions, which we couldn't
2488 tail-call to anyway. */
2490 if (currently_expanding_call++ != 0
2491 || !flag_optimize_sibling_calls
2492 || !rtx_equal_function_value_matters
2493 || any_pending_cleanups (1)
2494 || args_size.var)
2495 try_tail_call = try_tail_recursion = 0;
2497 /* Tail recursion fails, when we are not dealing with recursive calls. */
2498 if (!try_tail_recursion
2499 || TREE_CODE (addr) != ADDR_EXPR
2500 || TREE_OPERAND (addr, 0) != current_function_decl)
2501 try_tail_recursion = 0;
2503 /* Rest of purposes for tail call optimizations to fail. */
2504 if (
2505 #ifdef HAVE_sibcall_epilogue
2506 !HAVE_sibcall_epilogue
2507 #else
2509 #endif
2510 || !try_tail_call
2511 /* Doing sibling call optimization needs some work, since
2512 structure_value_addr can be allocated on the stack.
2513 It does not seem worth the effort since few optimizable
2514 sibling calls will return a structure. */
2515 || structure_value_addr != NULL_RTX
2516 /* Check whether the target is able to optimize the call
2517 into a sibcall. */
2518 || !(*targetm.function_ok_for_sibcall) (fndecl, exp)
2519 /* Functions that do not return exactly once may not be sibcall
2520 optimized. */
2521 || (flags & (ECF_RETURNS_TWICE | ECF_LONGJMP | ECF_NORETURN))
2522 || TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr)))
2523 /* If this function requires more stack slots than the current
2524 function, we cannot change it into a sibling call. */
2525 || args_size.constant > current_function_args_size
2526 /* If the callee pops its own arguments, then it must pop exactly
2527 the same number of arguments as the current function. */
2528 || RETURN_POPS_ARGS (fndecl, funtype, args_size.constant)
2529 != RETURN_POPS_ARGS (current_function_decl,
2530 TREE_TYPE (current_function_decl),
2531 current_function_args_size))
2532 try_tail_call = 0;
2534 if (try_tail_call || try_tail_recursion)
2536 int end, inc;
2537 actparms = NULL_TREE;
2538 /* Ok, we're going to give the tail call the old college try.
2539 This means we're going to evaluate the function arguments
2540 up to three times. There are two degrees of badness we can
2541 encounter, those that can be unsaved and those that can't.
2542 (See unsafe_for_reeval commentary for details.)
2544 Generate a new argument list. Pass safe arguments through
2545 unchanged. For the easy badness wrap them in UNSAVE_EXPRs.
2546 For hard badness, evaluate them now and put their resulting
2547 rtx in a temporary VAR_DECL.
2549 initialize_argument_information has ordered the array for the
2550 order to be pushed, and we must remember this when reconstructing
2551 the original argument order. */
2553 if (PUSH_ARGS_REVERSED)
2555 inc = 1;
2556 i = 0;
2557 end = num_actuals;
2559 else
2561 inc = -1;
2562 i = num_actuals - 1;
2563 end = -1;
2566 for (; i != end; i += inc)
2568 args[i].tree_value = fix_unsafe_tree (args[i].tree_value);
2569 /* We need to build actparms for optimize_tail_recursion. We can
2570 safely trash away TREE_PURPOSE, since it is unused by this
2571 function. */
2572 if (try_tail_recursion)
2573 actparms = tree_cons (NULL_TREE, args[i].tree_value, actparms);
2575 /* Do the same for the function address if it is an expression. */
2576 if (!fndecl)
2577 addr = fix_unsafe_tree (addr);
2578 /* Expanding one of those dangerous arguments could have added
2579 cleanups, but otherwise give it a whirl. */
2580 if (any_pending_cleanups (1))
2581 try_tail_call = try_tail_recursion = 0;
2584 /* Generate a tail recursion sequence when calling ourselves. */
2586 if (try_tail_recursion)
2588 /* We want to emit any pending stack adjustments before the tail
2589 recursion "call". That way we know any adjustment after the tail
2590 recursion call can be ignored if we indeed use the tail recursion
2591 call expansion. */
2592 int save_pending_stack_adjust = pending_stack_adjust;
2593 int save_stack_pointer_delta = stack_pointer_delta;
2595 /* Emit any queued insns now; otherwise they would end up in
2596 only one of the alternates. */
2597 emit_queue ();
2599 /* Use a new sequence to hold any RTL we generate. We do not even
2600 know if we will use this RTL yet. The final decision can not be
2601 made until after RTL generation for the entire function is
2602 complete. */
2603 start_sequence ();
2604 /* If expanding any of the arguments creates cleanups, we can't
2605 do a tailcall. So, we'll need to pop the pending cleanups
2606 list. If, however, all goes well, and there are no cleanups
2607 then the call to expand_start_target_temps will have no
2608 effect. */
2609 expand_start_target_temps ();
2610 if (optimize_tail_recursion (actparms, get_last_insn ()))
2612 if (any_pending_cleanups (1))
2613 try_tail_call = try_tail_recursion = 0;
2614 else
2615 tail_recursion_insns = get_insns ();
2617 expand_end_target_temps ();
2618 end_sequence ();
2620 /* Restore the original pending stack adjustment for the sibling and
2621 normal call cases below. */
2622 pending_stack_adjust = save_pending_stack_adjust;
2623 stack_pointer_delta = save_stack_pointer_delta;
2626 if (profile_arc_flag && (flags & ECF_FORK_OR_EXEC))
2628 /* A fork duplicates the profile information, and an exec discards
2629 it. We can't rely on fork/exec to be paired. So write out the
2630 profile information we have gathered so far, and clear it. */
2631 /* ??? When Linux's __clone is called with CLONE_VM set, profiling
2632 is subject to race conditions, just as with multithreaded
2633 programs. */
2635 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, "__gcov_flush"),
2636 LCT_ALWAYS_RETURN,
2637 VOIDmode, 0);
2640 /* Ensure current function's preferred stack boundary is at least
2641 what we need. We don't have to increase alignment for recursive
2642 functions. */
2643 if (cfun->preferred_stack_boundary < preferred_stack_boundary
2644 && fndecl != current_function_decl)
2645 cfun->preferred_stack_boundary = preferred_stack_boundary;
2646 if (fndecl == current_function_decl)
2647 cfun->recursive_call_emit = true;
2649 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
2651 function_call_count++;
2653 /* We want to make two insn chains; one for a sibling call, the other
2654 for a normal call. We will select one of the two chains after
2655 initial RTL generation is complete. */
2656 for (pass = try_tail_call ? 0 : 1; pass < 2; pass++)
2658 int sibcall_failure = 0;
2659 /* We want to emit any pending stack adjustments before the tail
2660 recursion "call". That way we know any adjustment after the tail
2661 recursion call can be ignored if we indeed use the tail recursion
2662 call expansion. */
2663 int save_pending_stack_adjust = 0;
2664 int save_stack_pointer_delta = 0;
2665 rtx insns;
2666 rtx before_call, next_arg_reg;
2668 if (pass == 0)
2670 /* Emit any queued insns now; otherwise they would end up in
2671 only one of the alternates. */
2672 emit_queue ();
2674 /* State variables we need to save and restore between
2675 iterations. */
2676 save_pending_stack_adjust = pending_stack_adjust;
2677 save_stack_pointer_delta = stack_pointer_delta;
2679 if (pass)
2680 flags &= ~ECF_SIBCALL;
2681 else
2682 flags |= ECF_SIBCALL;
2684 /* Other state variables that we must reinitialize each time
2685 through the loop (that are not initialized by the loop itself). */
2686 argblock = 0;
2687 call_fusage = 0;
2689 /* Start a new sequence for the normal call case.
2691 From this point on, if the sibling call fails, we want to set
2692 sibcall_failure instead of continuing the loop. */
2693 start_sequence ();
2695 if (pass == 0)
2697 /* We know at this point that there are not currently any
2698 pending cleanups. If, however, in the process of evaluating
2699 the arguments we were to create some, we'll need to be
2700 able to get rid of them. */
2701 expand_start_target_temps ();
2704 /* Don't let pending stack adjusts add up to too much.
2705 Also, do all pending adjustments now if there is any chance
2706 this might be a call to alloca or if we are expanding a sibling
2707 call sequence or if we are calling a function that is to return
2708 with stack pointer depressed. */
2709 if (pending_stack_adjust >= 32
2710 || (pending_stack_adjust > 0
2711 && (flags & (ECF_MAY_BE_ALLOCA | ECF_SP_DEPRESSED)))
2712 || pass == 0)
2713 do_pending_stack_adjust ();
2715 /* When calling a const function, we must pop the stack args right away,
2716 so that the pop is deleted or moved with the call. */
2717 if (pass && (flags & ECF_LIBCALL_BLOCK))
2718 NO_DEFER_POP;
2720 #ifdef FINAL_REG_PARM_STACK_SPACE
2721 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
2722 args_size.var);
2723 #endif
2724 /* Precompute any arguments as needed. */
2725 if (pass)
2726 precompute_arguments (flags, num_actuals, args);
2728 /* Now we are about to start emitting insns that can be deleted
2729 if a libcall is deleted. */
2730 if (pass && (flags & (ECF_LIBCALL_BLOCK | ECF_MALLOC)))
2731 start_sequence ();
2733 adjusted_args_size = args_size;
2734 /* Compute the actual size of the argument block required. The variable
2735 and constant sizes must be combined, the size may have to be rounded,
2736 and there may be a minimum required size. When generating a sibcall
2737 pattern, do not round up, since we'll be re-using whatever space our
2738 caller provided. */
2739 unadjusted_args_size
2740 = compute_argument_block_size (reg_parm_stack_space,
2741 &adjusted_args_size,
2742 (pass == 0 ? 0
2743 : preferred_stack_boundary));
2745 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
2747 /* The argument block when performing a sibling call is the
2748 incoming argument block. */
2749 if (pass == 0)
2751 argblock = virtual_incoming_args_rtx;
2752 argblock
2753 #ifdef STACK_GROWS_DOWNWARD
2754 = plus_constant (argblock, current_function_pretend_args_size);
2755 #else
2756 = plus_constant (argblock, -current_function_pretend_args_size);
2757 #endif
2758 stored_args_map = sbitmap_alloc (args_size.constant);
2759 sbitmap_zero (stored_args_map);
2762 /* If we have no actual push instructions, or shouldn't use them,
2763 make space for all args right now. */
2764 else if (adjusted_args_size.var != 0)
2766 if (old_stack_level == 0)
2768 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
2769 old_pending_adj = pending_stack_adjust;
2770 pending_stack_adjust = 0;
2771 /* stack_arg_under_construction says whether a stack arg is
2772 being constructed at the old stack level. Pushing the stack
2773 gets a clean outgoing argument block. */
2774 old_stack_arg_under_construction = stack_arg_under_construction;
2775 stack_arg_under_construction = 0;
2777 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
2779 else
2781 /* Note that we must go through the motions of allocating an argument
2782 block even if the size is zero because we may be storing args
2783 in the area reserved for register arguments, which may be part of
2784 the stack frame. */
2786 int needed = adjusted_args_size.constant;
2788 /* Store the maximum argument space used. It will be pushed by
2789 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2790 checking). */
2792 if (needed > current_function_outgoing_args_size)
2793 current_function_outgoing_args_size = needed;
2795 if (must_preallocate)
2797 if (ACCUMULATE_OUTGOING_ARGS)
2799 /* Since the stack pointer will never be pushed, it is
2800 possible for the evaluation of a parm to clobber
2801 something we have already written to the stack.
2802 Since most function calls on RISC machines do not use
2803 the stack, this is uncommon, but must work correctly.
2805 Therefore, we save any area of the stack that was already
2806 written and that we are using. Here we set up to do this
2807 by making a new stack usage map from the old one. The
2808 actual save will be done by store_one_arg.
2810 Another approach might be to try to reorder the argument
2811 evaluations to avoid this conflicting stack usage. */
2813 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2814 /* Since we will be writing into the entire argument area,
2815 the map must be allocated for its entire size, not just
2816 the part that is the responsibility of the caller. */
2817 needed += reg_parm_stack_space;
2818 #endif
2820 #ifdef ARGS_GROW_DOWNWARD
2821 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2822 needed + 1);
2823 #else
2824 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2825 needed);
2826 #endif
2827 stack_usage_map
2828 = (char *) alloca (highest_outgoing_arg_in_use);
2830 if (initial_highest_arg_in_use)
2831 memcpy (stack_usage_map, initial_stack_usage_map,
2832 initial_highest_arg_in_use);
2834 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2835 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
2836 (highest_outgoing_arg_in_use
2837 - initial_highest_arg_in_use));
2838 needed = 0;
2840 /* The address of the outgoing argument list must not be
2841 copied to a register here, because argblock would be left
2842 pointing to the wrong place after the call to
2843 allocate_dynamic_stack_space below. */
2845 argblock = virtual_outgoing_args_rtx;
2847 else
2849 if (inhibit_defer_pop == 0)
2851 /* Try to reuse some or all of the pending_stack_adjust
2852 to get this space. */
2853 needed
2854 = (combine_pending_stack_adjustment_and_call
2855 (unadjusted_args_size,
2856 &adjusted_args_size,
2857 preferred_unit_stack_boundary));
2859 /* combine_pending_stack_adjustment_and_call computes
2860 an adjustment before the arguments are allocated.
2861 Account for them and see whether or not the stack
2862 needs to go up or down. */
2863 needed = unadjusted_args_size - needed;
2865 if (needed < 0)
2867 /* We're releasing stack space. */
2868 /* ??? We can avoid any adjustment at all if we're
2869 already aligned. FIXME. */
2870 pending_stack_adjust = -needed;
2871 do_pending_stack_adjust ();
2872 needed = 0;
2874 else
2875 /* We need to allocate space. We'll do that in
2876 push_block below. */
2877 pending_stack_adjust = 0;
2880 /* Special case this because overhead of `push_block' in
2881 this case is non-trivial. */
2882 if (needed == 0)
2883 argblock = virtual_outgoing_args_rtx;
2884 else
2885 argblock = push_block (GEN_INT (needed), 0, 0);
2887 /* We only really need to call `copy_to_reg' in the case
2888 where push insns are going to be used to pass ARGBLOCK
2889 to a function call in ARGS. In that case, the stack
2890 pointer changes value from the allocation point to the
2891 call point, and hence the value of
2892 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2893 as well always do it. */
2894 argblock = copy_to_reg (argblock);
2896 /* The save/restore code in store_one_arg handles all
2897 cases except one: a constructor call (including a C
2898 function returning a BLKmode struct) to initialize
2899 an argument. */
2900 if (stack_arg_under_construction)
2902 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2903 rtx push_size = GEN_INT (reg_parm_stack_space
2904 + adjusted_args_size.constant);
2905 #else
2906 rtx push_size = GEN_INT (adjusted_args_size.constant);
2907 #endif
2908 if (old_stack_level == 0)
2910 emit_stack_save (SAVE_BLOCK, &old_stack_level,
2911 NULL_RTX);
2912 old_pending_adj = pending_stack_adjust;
2913 pending_stack_adjust = 0;
2914 /* stack_arg_under_construction says whether a stack
2915 arg is being constructed at the old stack level.
2916 Pushing the stack gets a clean outgoing argument
2917 block. */
2918 old_stack_arg_under_construction
2919 = stack_arg_under_construction;
2920 stack_arg_under_construction = 0;
2921 /* Make a new map for the new argument list. */
2922 stack_usage_map = (char *)
2923 alloca (highest_outgoing_arg_in_use);
2924 memset (stack_usage_map, 0, highest_outgoing_arg_in_use);
2925 highest_outgoing_arg_in_use = 0;
2927 allocate_dynamic_stack_space (push_size, NULL_RTX,
2928 BITS_PER_UNIT);
2930 /* If argument evaluation might modify the stack pointer,
2931 copy the address of the argument list to a register. */
2932 for (i = 0; i < num_actuals; i++)
2933 if (args[i].pass_on_stack)
2935 argblock = copy_addr_to_reg (argblock);
2936 break;
2942 compute_argument_addresses (args, argblock, num_actuals);
2944 /* If we push args individually in reverse order, perform stack alignment
2945 before the first push (the last arg). */
2946 if (PUSH_ARGS_REVERSED && argblock == 0
2947 && adjusted_args_size.constant != unadjusted_args_size)
2949 /* When the stack adjustment is pending, we get better code
2950 by combining the adjustments. */
2951 if (pending_stack_adjust
2952 && ! (flags & ECF_LIBCALL_BLOCK)
2953 && ! inhibit_defer_pop)
2955 pending_stack_adjust
2956 = (combine_pending_stack_adjustment_and_call
2957 (unadjusted_args_size,
2958 &adjusted_args_size,
2959 preferred_unit_stack_boundary));
2960 do_pending_stack_adjust ();
2962 else if (argblock == 0)
2963 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2964 - unadjusted_args_size));
2966 /* Now that the stack is properly aligned, pops can't safely
2967 be deferred during the evaluation of the arguments. */
2968 NO_DEFER_POP;
2970 funexp = rtx_for_function_call (fndecl, addr);
2972 /* Figure out the register where the value, if any, will come back. */
2973 valreg = 0;
2974 if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
2975 && ! structure_value_addr)
2977 if (pcc_struct_value)
2978 valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
2979 fndecl, (pass == 0));
2980 else
2981 valreg = hard_function_value (TREE_TYPE (exp), fndecl, (pass == 0));
2984 /* Precompute all register parameters. It isn't safe to compute anything
2985 once we have started filling any specific hard regs. */
2986 precompute_register_parameters (num_actuals, args, &reg_parm_seen);
2988 #ifdef REG_PARM_STACK_SPACE
2989 /* Save the fixed argument area if it's part of the caller's frame and
2990 is clobbered by argument setup for this call. */
2991 if (ACCUMULATE_OUTGOING_ARGS && pass)
2992 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
2993 &low_to_save, &high_to_save);
2994 #endif
2996 /* Now store (and compute if necessary) all non-register parms.
2997 These come before register parms, since they can require block-moves,
2998 which could clobber the registers used for register parms.
2999 Parms which have partial registers are not stored here,
3000 but we do preallocate space here if they want that. */
3002 for (i = 0; i < num_actuals; i++)
3003 if (args[i].reg == 0 || args[i].pass_on_stack)
3005 rtx before_arg = get_last_insn ();
3007 if (store_one_arg (&args[i], argblock, flags,
3008 adjusted_args_size.var != 0,
3009 reg_parm_stack_space)
3010 || (pass == 0
3011 && check_sibcall_argument_overlap (before_arg,
3012 &args[i], 1)))
3013 sibcall_failure = 1;
3016 /* If we have a parm that is passed in registers but not in memory
3017 and whose alignment does not permit a direct copy into registers,
3018 make a group of pseudos that correspond to each register that we
3019 will later fill. */
3020 if (STRICT_ALIGNMENT)
3021 store_unaligned_arguments_into_pseudos (args, num_actuals);
3023 /* Now store any partially-in-registers parm.
3024 This is the last place a block-move can happen. */
3025 if (reg_parm_seen)
3026 for (i = 0; i < num_actuals; i++)
3027 if (args[i].partial != 0 && ! args[i].pass_on_stack)
3029 rtx before_arg = get_last_insn ();
3031 if (store_one_arg (&args[i], argblock, flags,
3032 adjusted_args_size.var != 0,
3033 reg_parm_stack_space)
3034 || (pass == 0
3035 && check_sibcall_argument_overlap (before_arg,
3036 &args[i], 1)))
3037 sibcall_failure = 1;
3040 /* If we pushed args in forward order, perform stack alignment
3041 after pushing the last arg. */
3042 if (!PUSH_ARGS_REVERSED && argblock == 0)
3043 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
3044 - unadjusted_args_size));
3046 /* If register arguments require space on the stack and stack space
3047 was not preallocated, allocate stack space here for arguments
3048 passed in registers. */
3049 #ifdef OUTGOING_REG_PARM_STACK_SPACE
3050 if (!ACCUMULATE_OUTGOING_ARGS
3051 && must_preallocate == 0 && reg_parm_stack_space > 0)
3052 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
3053 #endif
3055 /* Pass the function the address in which to return a
3056 structure value. */
3057 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
3059 emit_move_insn (struct_value_rtx,
3060 force_reg (Pmode,
3061 force_operand (structure_value_addr,
3062 NULL_RTX)));
3064 if (GET_CODE (struct_value_rtx) == REG)
3065 use_reg (&call_fusage, struct_value_rtx);
3068 funexp = prepare_call_address (funexp, fndecl, &call_fusage,
3069 reg_parm_seen, pass == 0);
3071 load_register_parameters (args, num_actuals, &call_fusage, flags,
3072 pass == 0, &sibcall_failure);
3074 /* Perform postincrements before actually calling the function. */
3075 emit_queue ();
3077 /* Save a pointer to the last insn before the call, so that we can
3078 later safely search backwards to find the CALL_INSN. */
3079 before_call = get_last_insn ();
3081 /* Set up next argument register. For sibling calls on machines
3082 with register windows this should be the incoming register. */
3083 #ifdef FUNCTION_INCOMING_ARG
3084 if (pass == 0)
3085 next_arg_reg = FUNCTION_INCOMING_ARG (args_so_far, VOIDmode,
3086 void_type_node, 1);
3087 else
3088 #endif
3089 next_arg_reg = FUNCTION_ARG (args_so_far, VOIDmode,
3090 void_type_node, 1);
3092 /* All arguments and registers used for the call must be set up by
3093 now! */
3095 /* Stack must be properly aligned now. */
3096 if (pass && stack_pointer_delta % preferred_unit_stack_boundary)
3097 abort ();
3099 /* Generate the actual call instruction. */
3100 emit_call_1 (funexp, fndecl, funtype, unadjusted_args_size,
3101 adjusted_args_size.constant, struct_value_size,
3102 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
3103 flags, & args_so_far);
3105 /* Verify that we've deallocated all the stack we used. */
3106 if (pass
3107 && old_stack_allocated != stack_pointer_delta - pending_stack_adjust)
3108 abort ();
3110 /* If call is cse'able, make appropriate pair of reg-notes around it.
3111 Test valreg so we don't crash; may safely ignore `const'
3112 if return type is void. Disable for PARALLEL return values, because
3113 we have no way to move such values into a pseudo register. */
3114 if (pass && (flags & ECF_LIBCALL_BLOCK))
3116 rtx insns;
3118 if (valreg == 0 || GET_CODE (valreg) == PARALLEL)
3120 insns = get_insns ();
3121 end_sequence ();
3122 emit_insn (insns);
3124 else
3126 rtx note = 0;
3127 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3129 /* Mark the return value as a pointer if needed. */
3130 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3131 mark_reg_pointer (temp,
3132 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp))));
3134 /* Construct an "equal form" for the value which mentions all the
3135 arguments in order as well as the function name. */
3136 for (i = 0; i < num_actuals; i++)
3137 note = gen_rtx_EXPR_LIST (VOIDmode,
3138 args[i].initial_value, note);
3139 note = gen_rtx_EXPR_LIST (VOIDmode, funexp, note);
3141 insns = get_insns ();
3142 end_sequence ();
3144 if (flags & ECF_PURE)
3145 note = gen_rtx_EXPR_LIST (VOIDmode,
3146 gen_rtx_USE (VOIDmode,
3147 gen_rtx_MEM (BLKmode,
3148 gen_rtx_SCRATCH (VOIDmode))),
3149 note);
3151 emit_libcall_block (insns, temp, valreg, note);
3153 valreg = temp;
3156 else if (pass && (flags & ECF_MALLOC))
3158 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3159 rtx last, insns;
3161 /* The return value from a malloc-like function is a pointer. */
3162 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3163 mark_reg_pointer (temp, BIGGEST_ALIGNMENT);
3165 emit_move_insn (temp, valreg);
3167 /* The return value from a malloc-like function can not alias
3168 anything else. */
3169 last = get_last_insn ();
3170 REG_NOTES (last) =
3171 gen_rtx_EXPR_LIST (REG_NOALIAS, temp, REG_NOTES (last));
3173 /* Write out the sequence. */
3174 insns = get_insns ();
3175 end_sequence ();
3176 emit_insn (insns);
3177 valreg = temp;
3180 /* For calls to `setjmp', etc., inform flow.c it should complain
3181 if nonvolatile values are live. For functions that cannot return,
3182 inform flow that control does not fall through. */
3184 if ((flags & (ECF_NORETURN | ECF_LONGJMP)) || pass == 0)
3186 /* The barrier must be emitted
3187 immediately after the CALL_INSN. Some ports emit more
3188 than just a CALL_INSN above, so we must search for it here. */
3190 rtx last = get_last_insn ();
3191 while (GET_CODE (last) != CALL_INSN)
3193 last = PREV_INSN (last);
3194 /* There was no CALL_INSN? */
3195 if (last == before_call)
3196 abort ();
3199 emit_barrier_after (last);
3202 if (flags & ECF_LONGJMP)
3203 current_function_calls_longjmp = 1;
3205 /* If this function is returning into a memory location marked as
3206 readonly, it means it is initializing that location. But we normally
3207 treat functions as not clobbering such locations, so we need to
3208 specify that this one does. */
3209 if (target != 0 && GET_CODE (target) == MEM
3210 && structure_value_addr != 0 && RTX_UNCHANGING_P (target))
3211 emit_insn (gen_rtx_CLOBBER (VOIDmode, target));
3213 /* If value type not void, return an rtx for the value. */
3215 /* If there are cleanups to be called, don't use a hard reg as target.
3216 We need to double check this and see if it matters anymore. */
3217 if (any_pending_cleanups (1))
3219 if (target && REG_P (target)
3220 && REGNO (target) < FIRST_PSEUDO_REGISTER)
3221 target = 0;
3222 sibcall_failure = 1;
3225 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
3226 || ignore)
3227 target = const0_rtx;
3228 else if (structure_value_addr)
3230 if (target == 0 || GET_CODE (target) != MEM)
3232 target
3233 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3234 memory_address (TYPE_MODE (TREE_TYPE (exp)),
3235 structure_value_addr));
3236 set_mem_attributes (target, exp, 1);
3239 else if (pcc_struct_value)
3241 /* This is the special C++ case where we need to
3242 know what the true target was. We take care to
3243 never use this value more than once in one expression. */
3244 target = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3245 copy_to_reg (valreg));
3246 set_mem_attributes (target, exp, 1);
3248 /* Handle calls that return values in multiple non-contiguous locations.
3249 The Irix 6 ABI has examples of this. */
3250 else if (GET_CODE (valreg) == PARALLEL)
3252 if (target == 0)
3254 /* This will only be assigned once, so it can be readonly. */
3255 tree nt = build_qualified_type (TREE_TYPE (exp),
3256 (TYPE_QUALS (TREE_TYPE (exp))
3257 | TYPE_QUAL_CONST));
3259 target = assign_temp (nt, 0, 1, 1);
3260 preserve_temp_slots (target);
3263 if (! rtx_equal_p (target, valreg))
3264 emit_group_store (target, valreg,
3265 int_size_in_bytes (TREE_TYPE (exp)));
3267 /* We can not support sibling calls for this case. */
3268 sibcall_failure = 1;
3270 else if (target
3271 && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
3272 && GET_MODE (target) == GET_MODE (valreg))
3274 /* TARGET and VALREG cannot be equal at this point because the
3275 latter would not have REG_FUNCTION_VALUE_P true, while the
3276 former would if it were referring to the same register.
3278 If they refer to the same register, this move will be a no-op,
3279 except when function inlining is being done. */
3280 emit_move_insn (target, valreg);
3282 else if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
3284 target = copy_blkmode_from_reg (target, valreg, TREE_TYPE (exp));
3286 /* We can not support sibling calls for this case. */
3287 sibcall_failure = 1;
3289 else
3290 target = copy_to_reg (valreg);
3292 #ifdef PROMOTE_FUNCTION_RETURN
3293 /* If we promoted this return value, make the proper SUBREG. TARGET
3294 might be const0_rtx here, so be careful. */
3295 if (GET_CODE (target) == REG
3296 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
3297 && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
3299 tree type = TREE_TYPE (exp);
3300 int unsignedp = TREE_UNSIGNED (type);
3301 int offset = 0;
3303 /* If we don't promote as expected, something is wrong. */
3304 if (GET_MODE (target)
3305 != promote_mode (type, TYPE_MODE (type), &unsignedp, 1))
3306 abort ();
3308 if ((WORDS_BIG_ENDIAN || BYTES_BIG_ENDIAN)
3309 && GET_MODE_SIZE (GET_MODE (target))
3310 > GET_MODE_SIZE (TYPE_MODE (type)))
3312 offset = GET_MODE_SIZE (GET_MODE (target))
3313 - GET_MODE_SIZE (TYPE_MODE (type));
3314 if (! BYTES_BIG_ENDIAN)
3315 offset = (offset / UNITS_PER_WORD) * UNITS_PER_WORD;
3316 else if (! WORDS_BIG_ENDIAN)
3317 offset %= UNITS_PER_WORD;
3319 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
3320 SUBREG_PROMOTED_VAR_P (target) = 1;
3321 SUBREG_PROMOTED_UNSIGNED_SET (target, unsignedp);
3323 #endif
3325 /* If size of args is variable or this was a constructor call for a stack
3326 argument, restore saved stack-pointer value. */
3328 if (old_stack_level && ! (flags & ECF_SP_DEPRESSED))
3330 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
3331 pending_stack_adjust = old_pending_adj;
3332 stack_arg_under_construction = old_stack_arg_under_construction;
3333 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3334 stack_usage_map = initial_stack_usage_map;
3335 sibcall_failure = 1;
3337 else if (ACCUMULATE_OUTGOING_ARGS && pass)
3339 #ifdef REG_PARM_STACK_SPACE
3340 if (save_area)
3341 restore_fixed_argument_area (save_area, argblock,
3342 high_to_save, low_to_save);
3343 #endif
3345 /* If we saved any argument areas, restore them. */
3346 for (i = 0; i < num_actuals; i++)
3347 if (args[i].save_area)
3349 enum machine_mode save_mode = GET_MODE (args[i].save_area);
3350 rtx stack_area
3351 = gen_rtx_MEM (save_mode,
3352 memory_address (save_mode,
3353 XEXP (args[i].stack_slot, 0)));
3355 if (save_mode != BLKmode)
3356 emit_move_insn (stack_area, args[i].save_area);
3357 else
3358 emit_block_move (stack_area, args[i].save_area,
3359 GEN_INT (args[i].size.constant),
3360 BLOCK_OP_CALL_PARM);
3363 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3364 stack_usage_map = initial_stack_usage_map;
3367 /* If this was alloca, record the new stack level for nonlocal gotos.
3368 Check for the handler slots since we might not have a save area
3369 for non-local gotos. */
3371 if ((flags & ECF_MAY_BE_ALLOCA) && nonlocal_goto_handler_slots != 0)
3372 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
3374 /* Free up storage we no longer need. */
3375 for (i = 0; i < num_actuals; ++i)
3376 if (args[i].aligned_regs)
3377 free (args[i].aligned_regs);
3379 if (pass == 0)
3381 /* Undo the fake expand_start_target_temps we did earlier. If
3382 there had been any cleanups created, we've already set
3383 sibcall_failure. */
3384 expand_end_target_temps ();
3387 insns = get_insns ();
3388 end_sequence ();
3390 if (pass == 0)
3392 tail_call_insns = insns;
3394 /* Restore the pending stack adjustment now that we have
3395 finished generating the sibling call sequence. */
3397 pending_stack_adjust = save_pending_stack_adjust;
3398 stack_pointer_delta = save_stack_pointer_delta;
3400 /* Prepare arg structure for next iteration. */
3401 for (i = 0; i < num_actuals; i++)
3403 args[i].value = 0;
3404 args[i].aligned_regs = 0;
3405 args[i].stack = 0;
3408 sbitmap_free (stored_args_map);
3410 else
3411 normal_call_insns = insns;
3413 /* If something prevents making this a sibling call,
3414 zero out the sequence. */
3415 if (sibcall_failure)
3416 tail_call_insns = NULL_RTX;
3419 /* The function optimize_sibling_and_tail_recursive_calls doesn't
3420 handle CALL_PLACEHOLDERs inside other CALL_PLACEHOLDERs. This
3421 can happen if the arguments to this function call an inline
3422 function who's expansion contains another CALL_PLACEHOLDER.
3424 If there are any C_Ps in any of these sequences, replace them
3425 with their normal call. */
3427 for (insn = normal_call_insns; insn; insn = NEXT_INSN (insn))
3428 if (GET_CODE (insn) == CALL_INSN
3429 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3430 replace_call_placeholder (insn, sibcall_use_normal);
3432 for (insn = tail_call_insns; insn; insn = NEXT_INSN (insn))
3433 if (GET_CODE (insn) == CALL_INSN
3434 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3435 replace_call_placeholder (insn, sibcall_use_normal);
3437 for (insn = tail_recursion_insns; insn; insn = NEXT_INSN (insn))
3438 if (GET_CODE (insn) == CALL_INSN
3439 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3440 replace_call_placeholder (insn, sibcall_use_normal);
3442 /* If this was a potential tail recursion site, then emit a
3443 CALL_PLACEHOLDER with the normal and the tail recursion streams.
3444 One of them will be selected later. */
3445 if (tail_recursion_insns || tail_call_insns)
3447 /* The tail recursion label must be kept around. We could expose
3448 its use in the CALL_PLACEHOLDER, but that creates unwanted edges
3449 and makes determining true tail recursion sites difficult.
3451 So we set LABEL_PRESERVE_P here, then clear it when we select
3452 one of the call sequences after rtl generation is complete. */
3453 if (tail_recursion_insns)
3454 LABEL_PRESERVE_P (tail_recursion_label) = 1;
3455 emit_call_insn (gen_rtx_CALL_PLACEHOLDER (VOIDmode, normal_call_insns,
3456 tail_call_insns,
3457 tail_recursion_insns,
3458 tail_recursion_label));
3460 else
3461 emit_insn (normal_call_insns);
3463 currently_expanding_call--;
3465 /* If this function returns with the stack pointer depressed, ensure
3466 this block saves and restores the stack pointer, show it was
3467 changed, and adjust for any outgoing arg space. */
3468 if (flags & ECF_SP_DEPRESSED)
3470 clear_pending_stack_adjust ();
3471 emit_insn (gen_rtx (CLOBBER, VOIDmode, stack_pointer_rtx));
3472 emit_move_insn (virtual_stack_dynamic_rtx, stack_pointer_rtx);
3473 save_stack_pointer ();
3476 return target;
3479 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3480 The RETVAL parameter specifies whether return value needs to be saved, other
3481 parameters are documented in the emit_library_call function below. */
3483 static rtx
3484 emit_library_call_value_1 (retval, orgfun, value, fn_type, outmode, nargs, p)
3485 int retval;
3486 rtx orgfun;
3487 rtx value;
3488 enum libcall_type fn_type;
3489 enum machine_mode outmode;
3490 int nargs;
3491 va_list p;
3493 /* Total size in bytes of all the stack-parms scanned so far. */
3494 struct args_size args_size;
3495 /* Size of arguments before any adjustments (such as rounding). */
3496 struct args_size original_args_size;
3497 int argnum;
3498 rtx fun;
3499 int inc;
3500 int count;
3501 struct args_size alignment_pad;
3502 rtx argblock = 0;
3503 CUMULATIVE_ARGS args_so_far;
3504 struct arg
3506 rtx value;
3507 enum machine_mode mode;
3508 rtx reg;
3509 int partial;
3510 struct args_size offset;
3511 struct args_size size;
3512 rtx save_area;
3514 struct arg *argvec;
3515 int old_inhibit_defer_pop = inhibit_defer_pop;
3516 rtx call_fusage = 0;
3517 rtx mem_value = 0;
3518 rtx valreg;
3519 int pcc_struct_value = 0;
3520 int struct_value_size = 0;
3521 int flags;
3522 int reg_parm_stack_space = 0;
3523 int needed;
3524 rtx before_call;
3525 tree tfom; /* type_for_mode (outmode, 0) */
3527 #ifdef REG_PARM_STACK_SPACE
3528 /* Define the boundary of the register parm stack space that needs to be
3529 save, if any. */
3530 int low_to_save, high_to_save;
3531 rtx save_area = 0; /* Place that it is saved. */
3532 #endif
3534 /* Size of the stack reserved for parameter registers. */
3535 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3536 char *initial_stack_usage_map = stack_usage_map;
3538 #ifdef REG_PARM_STACK_SPACE
3539 #ifdef MAYBE_REG_PARM_STACK_SPACE
3540 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
3541 #else
3542 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3543 #endif
3544 #endif
3546 /* By default, library functions can not throw. */
3547 flags = ECF_NOTHROW;
3549 switch (fn_type)
3551 case LCT_NORMAL:
3552 break;
3553 case LCT_CONST:
3554 flags |= ECF_CONST;
3555 break;
3556 case LCT_PURE:
3557 flags |= ECF_PURE;
3558 break;
3559 case LCT_CONST_MAKE_BLOCK:
3560 flags |= ECF_CONST | ECF_LIBCALL_BLOCK;
3561 break;
3562 case LCT_PURE_MAKE_BLOCK:
3563 flags |= ECF_PURE | ECF_LIBCALL_BLOCK;
3564 break;
3565 case LCT_NORETURN:
3566 flags |= ECF_NORETURN;
3567 break;
3568 case LCT_THROW:
3569 flags = ECF_NORETURN;
3570 break;
3571 case LCT_ALWAYS_RETURN:
3572 flags = ECF_ALWAYS_RETURN;
3573 break;
3574 case LCT_RETURNS_TWICE:
3575 flags = ECF_RETURNS_TWICE;
3576 break;
3578 fun = orgfun;
3580 /* Ensure current function's preferred stack boundary is at least
3581 what we need. */
3582 if (cfun->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3583 cfun->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3585 /* If this kind of value comes back in memory,
3586 decide where in memory it should come back. */
3587 if (outmode != VOIDmode)
3589 tfom = (*lang_hooks.types.type_for_mode) (outmode, 0);
3590 if (aggregate_value_p (tfom))
3592 #ifdef PCC_STATIC_STRUCT_RETURN
3593 rtx pointer_reg
3594 = hard_function_value (build_pointer_type (tfom), 0, 0);
3595 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3596 pcc_struct_value = 1;
3597 if (value == 0)
3598 value = gen_reg_rtx (outmode);
3599 #else /* not PCC_STATIC_STRUCT_RETURN */
3600 struct_value_size = GET_MODE_SIZE (outmode);
3601 if (value != 0 && GET_CODE (value) == MEM)
3602 mem_value = value;
3603 else
3604 mem_value = assign_temp (tfom, 0, 1, 1);
3605 #endif
3606 /* This call returns a big structure. */
3607 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
3610 else
3611 tfom = void_type_node;
3613 /* ??? Unfinished: must pass the memory address as an argument. */
3615 /* Copy all the libcall-arguments out of the varargs data
3616 and into a vector ARGVEC.
3618 Compute how to pass each argument. We only support a very small subset
3619 of the full argument passing conventions to limit complexity here since
3620 library functions shouldn't have many args. */
3622 argvec = (struct arg *) alloca ((nargs + 1) * sizeof (struct arg));
3623 memset ((char *) argvec, 0, (nargs + 1) * sizeof (struct arg));
3625 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3626 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far, outmode, fun);
3627 #else
3628 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun, 0);
3629 #endif
3631 args_size.constant = 0;
3632 args_size.var = 0;
3634 count = 0;
3636 /* Now we are about to start emitting insns that can be deleted
3637 if a libcall is deleted. */
3638 if (flags & ECF_LIBCALL_BLOCK)
3639 start_sequence ();
3641 push_temp_slots ();
3643 /* If there's a structure value address to be passed,
3644 either pass it in the special place, or pass it as an extra argument. */
3645 if (mem_value && struct_value_rtx == 0 && ! pcc_struct_value)
3647 rtx addr = XEXP (mem_value, 0);
3648 nargs++;
3650 /* Make sure it is a reasonable operand for a move or push insn. */
3651 if (GET_CODE (addr) != REG && GET_CODE (addr) != MEM
3652 && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
3653 addr = force_operand (addr, NULL_RTX);
3655 argvec[count].value = addr;
3656 argvec[count].mode = Pmode;
3657 argvec[count].partial = 0;
3659 argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
3660 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3661 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far, Pmode, NULL_TREE, 1))
3662 abort ();
3663 #endif
3665 locate_and_pad_parm (Pmode, NULL_TREE,
3666 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3668 #else
3669 argvec[count].reg != 0,
3670 #endif
3671 NULL_TREE, &args_size, &argvec[count].offset,
3672 &argvec[count].size, &alignment_pad);
3674 if (argvec[count].reg == 0 || argvec[count].partial != 0
3675 || reg_parm_stack_space > 0)
3676 args_size.constant += argvec[count].size.constant;
3678 FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree) 0, 1);
3680 count++;
3683 for (; count < nargs; count++)
3685 rtx val = va_arg (p, rtx);
3686 enum machine_mode mode = va_arg (p, enum machine_mode);
3688 /* We cannot convert the arg value to the mode the library wants here;
3689 must do it earlier where we know the signedness of the arg. */
3690 if (mode == BLKmode
3691 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
3692 abort ();
3694 /* On some machines, there's no way to pass a float to a library fcn.
3695 Pass it as a double instead. */
3696 #ifdef LIBGCC_NEEDS_DOUBLE
3697 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
3698 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
3699 #endif
3701 /* There's no need to call protect_from_queue, because
3702 either emit_move_insn or emit_push_insn will do that. */
3704 /* Make sure it is a reasonable operand for a move or push insn. */
3705 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
3706 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
3707 val = force_operand (val, NULL_RTX);
3709 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3710 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
3712 rtx slot;
3713 int must_copy = 1
3714 #ifdef FUNCTION_ARG_CALLEE_COPIES
3715 && ! FUNCTION_ARG_CALLEE_COPIES (args_so_far, mode,
3716 NULL_TREE, 1)
3717 #endif
3720 /* loop.c won't look at CALL_INSN_FUNCTION_USAGE of const/pure
3721 functions, so we have to pretend this isn't such a function. */
3722 if (flags & ECF_LIBCALL_BLOCK)
3724 rtx insns = get_insns ();
3725 end_sequence ();
3726 emit_insn (insns);
3728 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
3730 /* If this was a CONST function, it is now PURE since
3731 it now reads memory. */
3732 if (flags & ECF_CONST)
3734 flags &= ~ECF_CONST;
3735 flags |= ECF_PURE;
3738 if (GET_MODE (val) == MEM && ! must_copy)
3739 slot = val;
3740 else if (must_copy)
3742 slot = assign_temp ((*lang_hooks.types.type_for_mode) (mode, 0),
3743 0, 1, 1);
3744 emit_move_insn (slot, val);
3746 else
3748 tree type = (*lang_hooks.types.type_for_mode) (mode, 0);
3750 slot
3751 = gen_rtx_MEM (mode,
3752 expand_expr (build1 (ADDR_EXPR,
3753 build_pointer_type (type),
3754 make_tree (type, val)),
3755 NULL_RTX, VOIDmode, 0));
3758 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3759 gen_rtx_USE (VOIDmode, slot),
3760 call_fusage);
3761 if (must_copy)
3762 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3763 gen_rtx_CLOBBER (VOIDmode,
3764 slot),
3765 call_fusage);
3767 mode = Pmode;
3768 val = force_operand (XEXP (slot, 0), NULL_RTX);
3770 #endif
3772 argvec[count].value = val;
3773 argvec[count].mode = mode;
3775 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
3777 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3778 argvec[count].partial
3779 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
3780 #else
3781 argvec[count].partial = 0;
3782 #endif
3784 locate_and_pad_parm (mode, NULL_TREE,
3785 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3787 #else
3788 argvec[count].reg != 0,
3789 #endif
3790 NULL_TREE, &args_size, &argvec[count].offset,
3791 &argvec[count].size, &alignment_pad);
3793 if (argvec[count].size.var)
3794 abort ();
3796 if (reg_parm_stack_space == 0 && argvec[count].partial)
3797 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
3799 if (argvec[count].reg == 0 || argvec[count].partial != 0
3800 || reg_parm_stack_space > 0)
3801 args_size.constant += argvec[count].size.constant;
3803 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree) 0, 1);
3806 #ifdef FINAL_REG_PARM_STACK_SPACE
3807 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
3808 args_size.var);
3809 #endif
3810 /* If this machine requires an external definition for library
3811 functions, write one out. */
3812 assemble_external_libcall (fun);
3814 original_args_size = args_size;
3815 args_size.constant = (((args_size.constant
3816 + stack_pointer_delta
3817 + STACK_BYTES - 1)
3818 / STACK_BYTES
3819 * STACK_BYTES)
3820 - stack_pointer_delta);
3822 args_size.constant = MAX (args_size.constant,
3823 reg_parm_stack_space);
3825 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3826 args_size.constant -= reg_parm_stack_space;
3827 #endif
3829 if (args_size.constant > current_function_outgoing_args_size)
3830 current_function_outgoing_args_size = args_size.constant;
3832 if (ACCUMULATE_OUTGOING_ARGS)
3834 /* Since the stack pointer will never be pushed, it is possible for
3835 the evaluation of a parm to clobber something we have already
3836 written to the stack. Since most function calls on RISC machines
3837 do not use the stack, this is uncommon, but must work correctly.
3839 Therefore, we save any area of the stack that was already written
3840 and that we are using. Here we set up to do this by making a new
3841 stack usage map from the old one.
3843 Another approach might be to try to reorder the argument
3844 evaluations to avoid this conflicting stack usage. */
3846 needed = args_size.constant;
3848 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3849 /* Since we will be writing into the entire argument area, the
3850 map must be allocated for its entire size, not just the part that
3851 is the responsibility of the caller. */
3852 needed += reg_parm_stack_space;
3853 #endif
3855 #ifdef ARGS_GROW_DOWNWARD
3856 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3857 needed + 1);
3858 #else
3859 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3860 needed);
3861 #endif
3862 stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
3864 if (initial_highest_arg_in_use)
3865 memcpy (stack_usage_map, initial_stack_usage_map,
3866 initial_highest_arg_in_use);
3868 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3869 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
3870 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
3871 needed = 0;
3873 /* We must be careful to use virtual regs before they're instantiated,
3874 and real regs afterwards. Loop optimization, for example, can create
3875 new libcalls after we've instantiated the virtual regs, and if we
3876 use virtuals anyway, they won't match the rtl patterns. */
3878 if (virtuals_instantiated)
3879 argblock = plus_constant (stack_pointer_rtx, STACK_POINTER_OFFSET);
3880 else
3881 argblock = virtual_outgoing_args_rtx;
3883 else
3885 if (!PUSH_ARGS)
3886 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
3889 /* If we push args individually in reverse order, perform stack alignment
3890 before the first push (the last arg). */
3891 if (argblock == 0 && PUSH_ARGS_REVERSED)
3892 anti_adjust_stack (GEN_INT (args_size.constant
3893 - original_args_size.constant));
3895 if (PUSH_ARGS_REVERSED)
3897 inc = -1;
3898 argnum = nargs - 1;
3900 else
3902 inc = 1;
3903 argnum = 0;
3906 #ifdef REG_PARM_STACK_SPACE
3907 if (ACCUMULATE_OUTGOING_ARGS)
3909 /* The argument list is the property of the called routine and it
3910 may clobber it. If the fixed area has been used for previous
3911 parameters, we must save and restore it. */
3912 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
3913 &low_to_save, &high_to_save);
3915 #endif
3917 /* Push the args that need to be pushed. */
3919 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3920 are to be pushed. */
3921 for (count = 0; count < nargs; count++, argnum += inc)
3923 enum machine_mode mode = argvec[argnum].mode;
3924 rtx val = argvec[argnum].value;
3925 rtx reg = argvec[argnum].reg;
3926 int partial = argvec[argnum].partial;
3927 int lower_bound = 0, upper_bound = 0, i;
3929 if (! (reg != 0 && partial == 0))
3931 if (ACCUMULATE_OUTGOING_ARGS)
3933 /* If this is being stored into a pre-allocated, fixed-size,
3934 stack area, save any previous data at that location. */
3936 #ifdef ARGS_GROW_DOWNWARD
3937 /* stack_slot is negative, but we want to index stack_usage_map
3938 with positive values. */
3939 upper_bound = -argvec[argnum].offset.constant + 1;
3940 lower_bound = upper_bound - argvec[argnum].size.constant;
3941 #else
3942 lower_bound = argvec[argnum].offset.constant;
3943 upper_bound = lower_bound + argvec[argnum].size.constant;
3944 #endif
3946 i = lower_bound;
3947 /* Don't worry about things in the fixed argument area;
3948 it has already been saved. */
3949 if (i < reg_parm_stack_space)
3950 i = reg_parm_stack_space;
3951 while (i < upper_bound && stack_usage_map[i] == 0)
3952 i++;
3954 if (i < upper_bound)
3956 /* We need to make a save area. See what mode we can make
3957 it. */
3958 enum machine_mode save_mode
3959 = mode_for_size (argvec[argnum].size.constant
3960 * BITS_PER_UNIT,
3961 MODE_INT, 1);
3962 rtx stack_area
3963 = gen_rtx_MEM
3964 (save_mode,
3965 memory_address
3966 (save_mode,
3967 plus_constant (argblock,
3968 argvec[argnum].offset.constant)));
3969 argvec[argnum].save_area = gen_reg_rtx (save_mode);
3971 emit_move_insn (argvec[argnum].save_area, stack_area);
3975 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, PARM_BOUNDARY,
3976 partial, reg, 0, argblock,
3977 GEN_INT (argvec[argnum].offset.constant),
3978 reg_parm_stack_space, ARGS_SIZE_RTX (alignment_pad));
3980 /* Now mark the segment we just used. */
3981 if (ACCUMULATE_OUTGOING_ARGS)
3982 for (i = lower_bound; i < upper_bound; i++)
3983 stack_usage_map[i] = 1;
3985 NO_DEFER_POP;
3989 /* If we pushed args in forward order, perform stack alignment
3990 after pushing the last arg. */
3991 if (argblock == 0 && !PUSH_ARGS_REVERSED)
3992 anti_adjust_stack (GEN_INT (args_size.constant
3993 - original_args_size.constant));
3995 if (PUSH_ARGS_REVERSED)
3996 argnum = nargs - 1;
3997 else
3998 argnum = 0;
4000 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0, 0);
4002 /* Now load any reg parms into their regs. */
4004 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4005 are to be pushed. */
4006 for (count = 0; count < nargs; count++, argnum += inc)
4008 rtx val = argvec[argnum].value;
4009 rtx reg = argvec[argnum].reg;
4010 int partial = argvec[argnum].partial;
4012 /* Handle calls that pass values in multiple non-contiguous
4013 locations. The PA64 has examples of this for library calls. */
4014 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4015 emit_group_load (reg, val, GET_MODE_SIZE (GET_MODE (val)));
4016 else if (reg != 0 && partial == 0)
4017 emit_move_insn (reg, val);
4019 NO_DEFER_POP;
4022 /* Any regs containing parms remain in use through the call. */
4023 for (count = 0; count < nargs; count++)
4025 rtx reg = argvec[count].reg;
4026 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4027 use_group_regs (&call_fusage, reg);
4028 else if (reg != 0)
4029 use_reg (&call_fusage, reg);
4032 /* Pass the function the address in which to return a structure value. */
4033 if (mem_value != 0 && struct_value_rtx != 0 && ! pcc_struct_value)
4035 emit_move_insn (struct_value_rtx,
4036 force_reg (Pmode,
4037 force_operand (XEXP (mem_value, 0),
4038 NULL_RTX)));
4039 if (GET_CODE (struct_value_rtx) == REG)
4040 use_reg (&call_fusage, struct_value_rtx);
4043 /* Don't allow popping to be deferred, since then
4044 cse'ing of library calls could delete a call and leave the pop. */
4045 NO_DEFER_POP;
4046 valreg = (mem_value == 0 && outmode != VOIDmode
4047 ? hard_libcall_value (outmode) : NULL_RTX);
4049 /* Stack must be properly aligned now. */
4050 if (stack_pointer_delta & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1))
4051 abort ();
4053 before_call = get_last_insn ();
4055 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4056 will set inhibit_defer_pop to that value. */
4057 /* The return type is needed to decide how many bytes the function pops.
4058 Signedness plays no role in that, so for simplicity, we pretend it's
4059 always signed. We also assume that the list of arguments passed has
4060 no impact, so we pretend it is unknown. */
4062 emit_call_1 (fun,
4063 get_identifier (XSTR (orgfun, 0)),
4064 build_function_type (tfom, NULL_TREE),
4065 original_args_size.constant, args_size.constant,
4066 struct_value_size,
4067 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
4068 valreg,
4069 old_inhibit_defer_pop + 1, call_fusage, flags, & args_so_far);
4071 /* For calls to `setjmp', etc., inform flow.c it should complain
4072 if nonvolatile values are live. For functions that cannot return,
4073 inform flow that control does not fall through. */
4075 if (flags & (ECF_NORETURN | ECF_LONGJMP))
4077 /* The barrier note must be emitted
4078 immediately after the CALL_INSN. Some ports emit more than
4079 just a CALL_INSN above, so we must search for it here. */
4081 rtx last = get_last_insn ();
4082 while (GET_CODE (last) != CALL_INSN)
4084 last = PREV_INSN (last);
4085 /* There was no CALL_INSN? */
4086 if (last == before_call)
4087 abort ();
4090 emit_barrier_after (last);
4093 /* Now restore inhibit_defer_pop to its actual original value. */
4094 OK_DEFER_POP;
4096 /* If call is cse'able, make appropriate pair of reg-notes around it.
4097 Test valreg so we don't crash; may safely ignore `const'
4098 if return type is void. Disable for PARALLEL return values, because
4099 we have no way to move such values into a pseudo register. */
4100 if (flags & ECF_LIBCALL_BLOCK)
4102 rtx insns;
4104 if (valreg == 0)
4106 insns = get_insns ();
4107 end_sequence ();
4108 emit_insn (insns);
4110 else
4112 rtx note = 0;
4113 rtx temp;
4114 int i;
4116 if (GET_CODE (valreg) == PARALLEL)
4118 temp = gen_reg_rtx (outmode);
4119 emit_group_store (temp, valreg, outmode);
4120 valreg = temp;
4123 temp = gen_reg_rtx (GET_MODE (valreg));
4125 /* Construct an "equal form" for the value which mentions all the
4126 arguments in order as well as the function name. */
4127 for (i = 0; i < nargs; i++)
4128 note = gen_rtx_EXPR_LIST (VOIDmode, argvec[i].value, note);
4129 note = gen_rtx_EXPR_LIST (VOIDmode, fun, note);
4131 insns = get_insns ();
4132 end_sequence ();
4134 if (flags & ECF_PURE)
4135 note = gen_rtx_EXPR_LIST (VOIDmode,
4136 gen_rtx_USE (VOIDmode,
4137 gen_rtx_MEM (BLKmode,
4138 gen_rtx_SCRATCH (VOIDmode))),
4139 note);
4141 emit_libcall_block (insns, temp, valreg, note);
4143 valreg = temp;
4146 pop_temp_slots ();
4148 /* Copy the value to the right place. */
4149 if (outmode != VOIDmode && retval)
4151 if (mem_value)
4153 if (value == 0)
4154 value = mem_value;
4155 if (value != mem_value)
4156 emit_move_insn (value, mem_value);
4158 else if (GET_CODE (valreg) == PARALLEL)
4160 if (value == 0)
4161 value = gen_reg_rtx (outmode);
4162 emit_group_store (value, valreg, outmode);
4164 else if (value != 0)
4165 emit_move_insn (value, valreg);
4166 else
4167 value = valreg;
4170 if (ACCUMULATE_OUTGOING_ARGS)
4172 #ifdef REG_PARM_STACK_SPACE
4173 if (save_area)
4174 restore_fixed_argument_area (save_area, argblock,
4175 high_to_save, low_to_save);
4176 #endif
4178 /* If we saved any argument areas, restore them. */
4179 for (count = 0; count < nargs; count++)
4180 if (argvec[count].save_area)
4182 enum machine_mode save_mode = GET_MODE (argvec[count].save_area);
4183 rtx stack_area
4184 = gen_rtx_MEM (save_mode,
4185 memory_address
4186 (save_mode,
4187 plus_constant (argblock,
4188 argvec[count].offset.constant)));
4190 emit_move_insn (stack_area, argvec[count].save_area);
4193 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4194 stack_usage_map = initial_stack_usage_map;
4197 return value;
4201 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4202 (emitting the queue unless NO_QUEUE is nonzero),
4203 for a value of mode OUTMODE,
4204 with NARGS different arguments, passed as alternating rtx values
4205 and machine_modes to convert them to.
4206 The rtx values should have been passed through protect_from_queue already.
4208 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for `const'
4209 calls, LCT_PURE for `pure' calls, LCT_CONST_MAKE_BLOCK for `const' calls
4210 which should be enclosed in REG_LIBCALL/REG_RETVAL notes,
4211 LCT_PURE_MAKE_BLOCK for `purep' calls which should be enclosed in
4212 REG_LIBCALL/REG_RETVAL notes with extra (use (memory (scratch)),
4213 or other LCT_ value for other types of library calls. */
4215 void
4216 emit_library_call VPARAMS((rtx orgfun, enum libcall_type fn_type,
4217 enum machine_mode outmode, int nargs, ...))
4219 VA_OPEN (p, nargs);
4220 VA_FIXEDARG (p, rtx, orgfun);
4221 VA_FIXEDARG (p, int, fn_type);
4222 VA_FIXEDARG (p, enum machine_mode, outmode);
4223 VA_FIXEDARG (p, int, nargs);
4225 emit_library_call_value_1 (0, orgfun, NULL_RTX, fn_type, outmode, nargs, p);
4227 VA_CLOSE (p);
4230 /* Like emit_library_call except that an extra argument, VALUE,
4231 comes second and says where to store the result.
4232 (If VALUE is zero, this function chooses a convenient way
4233 to return the value.
4235 This function returns an rtx for where the value is to be found.
4236 If VALUE is nonzero, VALUE is returned. */
4239 emit_library_call_value VPARAMS((rtx orgfun, rtx value,
4240 enum libcall_type fn_type,
4241 enum machine_mode outmode, int nargs, ...))
4243 rtx result;
4245 VA_OPEN (p, nargs);
4246 VA_FIXEDARG (p, rtx, orgfun);
4247 VA_FIXEDARG (p, rtx, value);
4248 VA_FIXEDARG (p, int, fn_type);
4249 VA_FIXEDARG (p, enum machine_mode, outmode);
4250 VA_FIXEDARG (p, int, nargs);
4252 result = emit_library_call_value_1 (1, orgfun, value, fn_type, outmode,
4253 nargs, p);
4255 VA_CLOSE (p);
4257 return result;
4260 /* Store a single argument for a function call
4261 into the register or memory area where it must be passed.
4262 *ARG describes the argument value and where to pass it.
4264 ARGBLOCK is the address of the stack-block for all the arguments,
4265 or 0 on a machine where arguments are pushed individually.
4267 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4268 so must be careful about how the stack is used.
4270 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4271 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4272 that we need not worry about saving and restoring the stack.
4274 FNDECL is the declaration of the function we are calling.
4276 Return nonzero if this arg should cause sibcall failure,
4277 zero otherwise. */
4279 static int
4280 store_one_arg (arg, argblock, flags, variable_size, reg_parm_stack_space)
4281 struct arg_data *arg;
4282 rtx argblock;
4283 int flags;
4284 int variable_size ATTRIBUTE_UNUSED;
4285 int reg_parm_stack_space;
4287 tree pval = arg->tree_value;
4288 rtx reg = 0;
4289 int partial = 0;
4290 int used = 0;
4291 int i, lower_bound = 0, upper_bound = 0;
4292 int sibcall_failure = 0;
4294 if (TREE_CODE (pval) == ERROR_MARK)
4295 return 1;
4297 /* Push a new temporary level for any temporaries we make for
4298 this argument. */
4299 push_temp_slots ();
4301 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
4303 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4304 save any previous data at that location. */
4305 if (argblock && ! variable_size && arg->stack)
4307 #ifdef ARGS_GROW_DOWNWARD
4308 /* stack_slot is negative, but we want to index stack_usage_map
4309 with positive values. */
4310 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4311 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
4312 else
4313 upper_bound = 0;
4315 lower_bound = upper_bound - arg->size.constant;
4316 #else
4317 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4318 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
4319 else
4320 lower_bound = 0;
4322 upper_bound = lower_bound + arg->size.constant;
4323 #endif
4325 i = lower_bound;
4326 /* Don't worry about things in the fixed argument area;
4327 it has already been saved. */
4328 if (i < reg_parm_stack_space)
4329 i = reg_parm_stack_space;
4330 while (i < upper_bound && stack_usage_map[i] == 0)
4331 i++;
4333 if (i < upper_bound)
4335 /* We need to make a save area. See what mode we can make it. */
4336 enum machine_mode save_mode
4337 = mode_for_size (arg->size.constant * BITS_PER_UNIT, MODE_INT, 1);
4338 rtx stack_area
4339 = gen_rtx_MEM (save_mode,
4340 memory_address (save_mode,
4341 XEXP (arg->stack_slot, 0)));
4343 if (save_mode == BLKmode)
4345 tree ot = TREE_TYPE (arg->tree_value);
4346 tree nt = build_qualified_type (ot, (TYPE_QUALS (ot)
4347 | TYPE_QUAL_CONST));
4349 arg->save_area = assign_temp (nt, 0, 1, 1);
4350 preserve_temp_slots (arg->save_area);
4351 emit_block_move (validize_mem (arg->save_area), stack_area,
4352 expr_size (arg->tree_value),
4353 BLOCK_OP_CALL_PARM);
4355 else
4357 arg->save_area = gen_reg_rtx (save_mode);
4358 emit_move_insn (arg->save_area, stack_area);
4364 /* If this isn't going to be placed on both the stack and in registers,
4365 set up the register and number of words. */
4366 if (! arg->pass_on_stack)
4368 if (flags & ECF_SIBCALL)
4369 reg = arg->tail_call_reg;
4370 else
4371 reg = arg->reg;
4372 partial = arg->partial;
4375 if (reg != 0 && partial == 0)
4376 /* Being passed entirely in a register. We shouldn't be called in
4377 this case. */
4378 abort ();
4380 /* If this arg needs special alignment, don't load the registers
4381 here. */
4382 if (arg->n_aligned_regs != 0)
4383 reg = 0;
4385 /* If this is being passed partially in a register, we can't evaluate
4386 it directly into its stack slot. Otherwise, we can. */
4387 if (arg->value == 0)
4389 /* stack_arg_under_construction is nonzero if a function argument is
4390 being evaluated directly into the outgoing argument list and
4391 expand_call must take special action to preserve the argument list
4392 if it is called recursively.
4394 For scalar function arguments stack_usage_map is sufficient to
4395 determine which stack slots must be saved and restored. Scalar
4396 arguments in general have pass_on_stack == 0.
4398 If this argument is initialized by a function which takes the
4399 address of the argument (a C++ constructor or a C function
4400 returning a BLKmode structure), then stack_usage_map is
4401 insufficient and expand_call must push the stack around the
4402 function call. Such arguments have pass_on_stack == 1.
4404 Note that it is always safe to set stack_arg_under_construction,
4405 but this generates suboptimal code if set when not needed. */
4407 if (arg->pass_on_stack)
4408 stack_arg_under_construction++;
4410 arg->value = expand_expr (pval,
4411 (partial
4412 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
4413 ? NULL_RTX : arg->stack,
4414 VOIDmode, EXPAND_STACK_PARM);
4416 /* If we are promoting object (or for any other reason) the mode
4417 doesn't agree, convert the mode. */
4419 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
4420 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
4421 arg->value, arg->unsignedp);
4423 if (arg->pass_on_stack)
4424 stack_arg_under_construction--;
4427 /* Don't allow anything left on stack from computation
4428 of argument to alloca. */
4429 if (flags & ECF_MAY_BE_ALLOCA)
4430 do_pending_stack_adjust ();
4432 if (arg->value == arg->stack)
4433 /* If the value is already in the stack slot, we are done. */
4435 else if (arg->mode != BLKmode)
4437 int size;
4439 /* Argument is a scalar, not entirely passed in registers.
4440 (If part is passed in registers, arg->partial says how much
4441 and emit_push_insn will take care of putting it there.)
4443 Push it, and if its size is less than the
4444 amount of space allocated to it,
4445 also bump stack pointer by the additional space.
4446 Note that in C the default argument promotions
4447 will prevent such mismatches. */
4449 size = GET_MODE_SIZE (arg->mode);
4450 /* Compute how much space the push instruction will push.
4451 On many machines, pushing a byte will advance the stack
4452 pointer by a halfword. */
4453 #ifdef PUSH_ROUNDING
4454 size = PUSH_ROUNDING (size);
4455 #endif
4456 used = size;
4458 /* Compute how much space the argument should get:
4459 round up to a multiple of the alignment for arguments. */
4460 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
4461 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
4462 / (PARM_BOUNDARY / BITS_PER_UNIT))
4463 * (PARM_BOUNDARY / BITS_PER_UNIT));
4465 /* This isn't already where we want it on the stack, so put it there.
4466 This can either be done with push or copy insns. */
4467 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
4468 PARM_BOUNDARY, partial, reg, used - size, argblock,
4469 ARGS_SIZE_RTX (arg->offset), reg_parm_stack_space,
4470 ARGS_SIZE_RTX (arg->alignment_pad));
4472 /* Unless this is a partially-in-register argument, the argument is now
4473 in the stack. */
4474 if (partial == 0)
4475 arg->value = arg->stack;
4477 else
4479 /* BLKmode, at least partly to be pushed. */
4481 unsigned int parm_align;
4482 int excess;
4483 rtx size_rtx;
4485 /* Pushing a nonscalar.
4486 If part is passed in registers, PARTIAL says how much
4487 and emit_push_insn will take care of putting it there. */
4489 /* Round its size up to a multiple
4490 of the allocation unit for arguments. */
4492 if (arg->size.var != 0)
4494 excess = 0;
4495 size_rtx = ARGS_SIZE_RTX (arg->size);
4497 else
4499 /* PUSH_ROUNDING has no effect on us, because
4500 emit_push_insn for BLKmode is careful to avoid it. */
4501 excess = (arg->size.constant - int_size_in_bytes (TREE_TYPE (pval))
4502 + partial * UNITS_PER_WORD);
4503 size_rtx = expand_expr (size_in_bytes (TREE_TYPE (pval)),
4504 NULL_RTX, TYPE_MODE (sizetype), 0);
4507 /* Some types will require stricter alignment, which will be
4508 provided for elsewhere in argument layout. */
4509 parm_align = MAX (PARM_BOUNDARY, TYPE_ALIGN (TREE_TYPE (pval)));
4511 /* When an argument is padded down, the block is aligned to
4512 PARM_BOUNDARY, but the actual argument isn't. */
4513 if (FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)) == downward)
4515 if (arg->size.var)
4516 parm_align = BITS_PER_UNIT;
4517 else if (excess)
4519 unsigned int excess_align = (excess & -excess) * BITS_PER_UNIT;
4520 parm_align = MIN (parm_align, excess_align);
4524 if ((flags & ECF_SIBCALL) && GET_CODE (arg->value) == MEM)
4526 /* emit_push_insn might not work properly if arg->value and
4527 argblock + arg->offset areas overlap. */
4528 rtx x = arg->value;
4529 int i = 0;
4531 if (XEXP (x, 0) == current_function_internal_arg_pointer
4532 || (GET_CODE (XEXP (x, 0)) == PLUS
4533 && XEXP (XEXP (x, 0), 0) ==
4534 current_function_internal_arg_pointer
4535 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT))
4537 if (XEXP (x, 0) != current_function_internal_arg_pointer)
4538 i = INTVAL (XEXP (XEXP (x, 0), 1));
4540 /* expand_call should ensure this */
4541 if (arg->offset.var || GET_CODE (size_rtx) != CONST_INT)
4542 abort ();
4544 if (arg->offset.constant > i)
4546 if (arg->offset.constant < i + INTVAL (size_rtx))
4547 sibcall_failure = 1;
4549 else if (arg->offset.constant < i)
4551 if (i < arg->offset.constant + INTVAL (size_rtx))
4552 sibcall_failure = 1;
4557 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
4558 parm_align, partial, reg, excess, argblock,
4559 ARGS_SIZE_RTX (arg->offset), reg_parm_stack_space,
4560 ARGS_SIZE_RTX (arg->alignment_pad));
4562 /* Unless this is a partially-in-register argument, the argument is now
4563 in the stack.
4565 ??? Unlike the case above, in which we want the actual
4566 address of the data, so that we can load it directly into a
4567 register, here we want the address of the stack slot, so that
4568 it's properly aligned for word-by-word copying or something
4569 like that. It's not clear that this is always correct. */
4570 if (partial == 0)
4571 arg->value = arg->stack_slot;
4574 /* Mark all slots this store used. */
4575 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL)
4576 && argblock && ! variable_size && arg->stack)
4577 for (i = lower_bound; i < upper_bound; i++)
4578 stack_usage_map[i] = 1;
4580 /* Once we have pushed something, pops can't safely
4581 be deferred during the rest of the arguments. */
4582 NO_DEFER_POP;
4584 /* ANSI doesn't require a sequence point here,
4585 but PCC has one, so this will avoid some problems. */
4586 emit_queue ();
4588 /* Free any temporary slots made in processing this argument. Show
4589 that we might have taken the address of something and pushed that
4590 as an operand. */
4591 preserve_temp_slots (NULL_RTX);
4592 free_temp_slots ();
4593 pop_temp_slots ();
4595 return sibcall_failure;
4598 /* Nonzero if we do not know how to pass TYPE solely in registers.
4599 We cannot do so in the following cases:
4601 - if the type has variable size
4602 - if the type is marked as addressable (it is required to be constructed
4603 into the stack)
4604 - if the padding and mode of the type is such that a copy into a register
4605 would put it into the wrong part of the register.
4607 Which padding can't be supported depends on the byte endianness.
4609 A value in a register is implicitly padded at the most significant end.
4610 On a big-endian machine, that is the lower end in memory.
4611 So a value padded in memory at the upper end can't go in a register.
4612 For a little-endian machine, the reverse is true. */
4614 bool
4615 default_must_pass_in_stack (mode, type)
4616 enum machine_mode mode;
4617 tree type;
4619 if (!type)
4620 return false;
4622 /* If the type has variable size... */
4623 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4624 return true;
4626 /* If the type is marked as addressable (it is required
4627 to be constructed into the stack)... */
4628 if (TREE_ADDRESSABLE (type))
4629 return true;
4631 /* If the padding and mode of the type is such that a copy into
4632 a register would put it into the wrong part of the register. */
4633 if (mode == BLKmode
4634 && int_size_in_bytes (type) % (PARM_BOUNDARY / BITS_PER_UNIT)
4635 && (FUNCTION_ARG_PADDING (mode, type)
4636 == (BYTES_BIG_ENDIAN ? upward : downward)))
4637 return true;
4639 return false;