/gcc
[official-gcc.git] / gcc / calls.c
blob4d54fc6de0533c2377c1d4d9b1032422bdc689f6
1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989-2017 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
20 #include "config.h"
21 #include "system.h"
22 #include "coretypes.h"
23 #include "backend.h"
24 #include "target.h"
25 #include "rtl.h"
26 #include "tree.h"
27 #include "gimple.h"
28 #include "predict.h"
29 #include "memmodel.h"
30 #include "tm_p.h"
31 #include "stringpool.h"
32 #include "expmed.h"
33 #include "optabs.h"
34 #include "emit-rtl.h"
35 #include "cgraph.h"
36 #include "diagnostic-core.h"
37 #include "fold-const.h"
38 #include "stor-layout.h"
39 #include "varasm.h"
40 #include "internal-fn.h"
41 #include "dojump.h"
42 #include "explow.h"
43 #include "calls.h"
44 #include "expr.h"
45 #include "output.h"
46 #include "langhooks.h"
47 #include "except.h"
48 #include "dbgcnt.h"
49 #include "rtl-iter.h"
50 #include "tree-chkp.h"
51 #include "tree-vrp.h"
52 #include "tree-ssanames.h"
53 #include "rtl-chkp.h"
54 #include "intl.h"
55 #include "stringpool.h"
56 #include "attribs.h"
58 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
59 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
61 /* Data structure and subroutines used within expand_call. */
63 struct arg_data
65 /* Tree node for this argument. */
66 tree tree_value;
67 /* Mode for value; TYPE_MODE unless promoted. */
68 machine_mode mode;
69 /* Current RTL value for argument, or 0 if it isn't precomputed. */
70 rtx value;
71 /* Initially-compute RTL value for argument; only for const functions. */
72 rtx initial_value;
73 /* Register to pass this argument in, 0 if passed on stack, or an
74 PARALLEL if the arg is to be copied into multiple non-contiguous
75 registers. */
76 rtx reg;
77 /* Register to pass this argument in when generating tail call sequence.
78 This is not the same register as for normal calls on machines with
79 register windows. */
80 rtx tail_call_reg;
81 /* If REG is a PARALLEL, this is a copy of VALUE pulled into the correct
82 form for emit_group_move. */
83 rtx parallel_value;
84 /* If value is passed in neither reg nor stack, this field holds a number
85 of a special slot to be used. */
86 rtx special_slot;
87 /* For pointer bounds hold an index of parm bounds are bound to. -1 if
88 there is no such pointer. */
89 int pointer_arg;
90 /* If pointer_arg refers a structure, then pointer_offset holds an offset
91 of a pointer in this structure. */
92 int pointer_offset;
93 /* If REG was promoted from the actual mode of the argument expression,
94 indicates whether the promotion is sign- or zero-extended. */
95 int unsignedp;
96 /* Number of bytes to put in registers. 0 means put the whole arg
97 in registers. Also 0 if not passed in registers. */
98 int partial;
99 /* Nonzero if argument must be passed on stack.
100 Note that some arguments may be passed on the stack
101 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
102 pass_on_stack identifies arguments that *cannot* go in registers. */
103 int pass_on_stack;
104 /* Some fields packaged up for locate_and_pad_parm. */
105 struct locate_and_pad_arg_data locate;
106 /* Location on the stack at which parameter should be stored. The store
107 has already been done if STACK == VALUE. */
108 rtx stack;
109 /* Location on the stack of the start of this argument slot. This can
110 differ from STACK if this arg pads downward. This location is known
111 to be aligned to TARGET_FUNCTION_ARG_BOUNDARY. */
112 rtx stack_slot;
113 /* Place that this stack area has been saved, if needed. */
114 rtx save_area;
115 /* If an argument's alignment does not permit direct copying into registers,
116 copy in smaller-sized pieces into pseudos. These are stored in a
117 block pointed to by this field. The next field says how many
118 word-sized pseudos we made. */
119 rtx *aligned_regs;
120 int n_aligned_regs;
123 /* A vector of one char per byte of stack space. A byte if nonzero if
124 the corresponding stack location has been used.
125 This vector is used to prevent a function call within an argument from
126 clobbering any stack already set up. */
127 static char *stack_usage_map;
129 /* Size of STACK_USAGE_MAP. */
130 static int highest_outgoing_arg_in_use;
132 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
133 stack location's tail call argument has been already stored into the stack.
134 This bitmap is used to prevent sibling call optimization if function tries
135 to use parent's incoming argument slots when they have been already
136 overwritten with tail call arguments. */
137 static sbitmap stored_args_map;
139 /* stack_arg_under_construction is nonzero when an argument may be
140 initialized with a constructor call (including a C function that
141 returns a BLKmode struct) and expand_call must take special action
142 to make sure the object being constructed does not overlap the
143 argument list for the constructor call. */
144 static int stack_arg_under_construction;
146 static void emit_call_1 (rtx, tree, tree, tree, HOST_WIDE_INT, HOST_WIDE_INT,
147 HOST_WIDE_INT, rtx, rtx, int, rtx, int,
148 cumulative_args_t);
149 static void precompute_register_parameters (int, struct arg_data *, int *);
150 static void store_bounds (struct arg_data *, struct arg_data *);
151 static int store_one_arg (struct arg_data *, rtx, int, int, int);
152 static void store_unaligned_arguments_into_pseudos (struct arg_data *, int);
153 static int finalize_must_preallocate (int, int, struct arg_data *,
154 struct args_size *);
155 static void precompute_arguments (int, struct arg_data *);
156 static int compute_argument_block_size (int, struct args_size *, tree, tree, int);
157 static void initialize_argument_information (int, struct arg_data *,
158 struct args_size *, int,
159 tree, tree,
160 tree, tree, cumulative_args_t, int,
161 rtx *, int *, int *, int *,
162 bool *, bool);
163 static void compute_argument_addresses (struct arg_data *, rtx, int);
164 static rtx rtx_for_function_call (tree, tree);
165 static void load_register_parameters (struct arg_data *, int, rtx *, int,
166 int, int *);
167 static int special_function_p (const_tree, int);
168 static int check_sibcall_argument_overlap_1 (rtx);
169 static int check_sibcall_argument_overlap (rtx_insn *, struct arg_data *, int);
171 static int combine_pending_stack_adjustment_and_call (int, struct args_size *,
172 unsigned int);
173 static tree split_complex_types (tree);
175 #ifdef REG_PARM_STACK_SPACE
176 static rtx save_fixed_argument_area (int, rtx, int *, int *);
177 static void restore_fixed_argument_area (rtx, rtx, int, int);
178 #endif
180 /* Force FUNEXP into a form suitable for the address of a CALL,
181 and return that as an rtx. Also load the static chain register
182 if FNDECL is a nested function.
184 CALL_FUSAGE points to a variable holding the prospective
185 CALL_INSN_FUNCTION_USAGE information. */
188 prepare_call_address (tree fndecl_or_type, rtx funexp, rtx static_chain_value,
189 rtx *call_fusage, int reg_parm_seen, int flags)
191 /* Make a valid memory address and copy constants through pseudo-regs,
192 but not for a constant address if -fno-function-cse. */
193 if (GET_CODE (funexp) != SYMBOL_REF)
195 /* If it's an indirect call by descriptor, generate code to perform
196 runtime identification of the pointer and load the descriptor. */
197 if ((flags & ECF_BY_DESCRIPTOR) && !flag_trampolines)
199 const int bit_val = targetm.calls.custom_function_descriptors;
200 rtx call_lab = gen_label_rtx ();
202 gcc_assert (fndecl_or_type && TYPE_P (fndecl_or_type));
203 fndecl_or_type
204 = build_decl (UNKNOWN_LOCATION, FUNCTION_DECL, NULL_TREE,
205 fndecl_or_type);
206 DECL_STATIC_CHAIN (fndecl_or_type) = 1;
207 rtx chain = targetm.calls.static_chain (fndecl_or_type, false);
209 if (GET_MODE (funexp) != Pmode)
210 funexp = convert_memory_address (Pmode, funexp);
212 /* Avoid long live ranges around function calls. */
213 funexp = copy_to_mode_reg (Pmode, funexp);
215 if (REG_P (chain))
216 emit_insn (gen_rtx_CLOBBER (VOIDmode, chain));
218 /* Emit the runtime identification pattern. */
219 rtx mask = gen_rtx_AND (Pmode, funexp, GEN_INT (bit_val));
220 emit_cmp_and_jump_insns (mask, const0_rtx, EQ, NULL_RTX, Pmode, 1,
221 call_lab);
223 /* Statically predict the branch to very likely taken. */
224 rtx_insn *insn = get_last_insn ();
225 if (JUMP_P (insn))
226 predict_insn_def (insn, PRED_BUILTIN_EXPECT, TAKEN);
228 /* Load the descriptor. */
229 rtx mem = gen_rtx_MEM (ptr_mode,
230 plus_constant (Pmode, funexp, - bit_val));
231 MEM_NOTRAP_P (mem) = 1;
232 mem = convert_memory_address (Pmode, mem);
233 emit_move_insn (chain, mem);
235 mem = gen_rtx_MEM (ptr_mode,
236 plus_constant (Pmode, funexp,
237 POINTER_SIZE / BITS_PER_UNIT
238 - bit_val));
239 MEM_NOTRAP_P (mem) = 1;
240 mem = convert_memory_address (Pmode, mem);
241 emit_move_insn (funexp, mem);
243 emit_label (call_lab);
245 if (REG_P (chain))
247 use_reg (call_fusage, chain);
248 STATIC_CHAIN_REG_P (chain) = 1;
251 /* Make sure we're not going to be overwritten below. */
252 gcc_assert (!static_chain_value);
255 /* If we are using registers for parameters, force the
256 function address into a register now. */
257 funexp = ((reg_parm_seen
258 && targetm.small_register_classes_for_mode_p (FUNCTION_MODE))
259 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
260 : memory_address (FUNCTION_MODE, funexp));
262 else
264 /* funexp could be a SYMBOL_REF represents a function pointer which is
265 of ptr_mode. In this case, it should be converted into address mode
266 to be a valid address for memory rtx pattern. See PR 64971. */
267 if (GET_MODE (funexp) != Pmode)
268 funexp = convert_memory_address (Pmode, funexp);
270 if (!(flags & ECF_SIBCALL))
272 if (!NO_FUNCTION_CSE && optimize && ! flag_no_function_cse)
273 funexp = force_reg (Pmode, funexp);
277 if (static_chain_value != 0
278 && (TREE_CODE (fndecl_or_type) != FUNCTION_DECL
279 || DECL_STATIC_CHAIN (fndecl_or_type)))
281 rtx chain;
283 chain = targetm.calls.static_chain (fndecl_or_type, false);
284 static_chain_value = convert_memory_address (Pmode, static_chain_value);
286 emit_move_insn (chain, static_chain_value);
287 if (REG_P (chain))
289 use_reg (call_fusage, chain);
290 STATIC_CHAIN_REG_P (chain) = 1;
294 return funexp;
297 /* Generate instructions to call function FUNEXP,
298 and optionally pop the results.
299 The CALL_INSN is the first insn generated.
301 FNDECL is the declaration node of the function. This is given to the
302 hook TARGET_RETURN_POPS_ARGS to determine whether this function pops
303 its own args.
305 FUNTYPE is the data type of the function. This is given to the hook
306 TARGET_RETURN_POPS_ARGS to determine whether this function pops its
307 own args. We used to allow an identifier for library functions, but
308 that doesn't work when the return type is an aggregate type and the
309 calling convention says that the pointer to this aggregate is to be
310 popped by the callee.
312 STACK_SIZE is the number of bytes of arguments on the stack,
313 ROUNDED_STACK_SIZE is that number rounded up to
314 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
315 both to put into the call insn and to generate explicit popping
316 code if necessary.
318 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
319 It is zero if this call doesn't want a structure value.
321 NEXT_ARG_REG is the rtx that results from executing
322 targetm.calls.function_arg (&args_so_far, VOIDmode, void_type_node, true)
323 just after all the args have had their registers assigned.
324 This could be whatever you like, but normally it is the first
325 arg-register beyond those used for args in this call,
326 or 0 if all the arg-registers are used in this call.
327 It is passed on to `gen_call' so you can put this info in the call insn.
329 VALREG is a hard register in which a value is returned,
330 or 0 if the call does not return a value.
332 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
333 the args to this call were processed.
334 We restore `inhibit_defer_pop' to that value.
336 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
337 denote registers used by the called function. */
339 static void
340 emit_call_1 (rtx funexp, tree fntree ATTRIBUTE_UNUSED, tree fndecl ATTRIBUTE_UNUSED,
341 tree funtype ATTRIBUTE_UNUSED,
342 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED,
343 HOST_WIDE_INT rounded_stack_size,
344 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED,
345 rtx next_arg_reg ATTRIBUTE_UNUSED, rtx valreg,
346 int old_inhibit_defer_pop, rtx call_fusage, int ecf_flags,
347 cumulative_args_t args_so_far ATTRIBUTE_UNUSED)
349 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
350 rtx call, funmem, pat;
351 int already_popped = 0;
352 HOST_WIDE_INT n_popped = 0;
354 /* Sibling call patterns never pop arguments (no sibcall(_value)_pop
355 patterns exist). Any popping that the callee does on return will
356 be from our caller's frame rather than ours. */
357 if (!(ecf_flags & ECF_SIBCALL))
359 n_popped += targetm.calls.return_pops_args (fndecl, funtype, stack_size);
361 #ifdef CALL_POPS_ARGS
362 n_popped += CALL_POPS_ARGS (*get_cumulative_args (args_so_far));
363 #endif
366 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
367 and we don't want to load it into a register as an optimization,
368 because prepare_call_address already did it if it should be done. */
369 if (GET_CODE (funexp) != SYMBOL_REF)
370 funexp = memory_address (FUNCTION_MODE, funexp);
372 funmem = gen_rtx_MEM (FUNCTION_MODE, funexp);
373 if (fndecl && TREE_CODE (fndecl) == FUNCTION_DECL)
375 tree t = fndecl;
377 /* Although a built-in FUNCTION_DECL and its non-__builtin
378 counterpart compare equal and get a shared mem_attrs, they
379 produce different dump output in compare-debug compilations,
380 if an entry gets garbage collected in one compilation, then
381 adds a different (but equivalent) entry, while the other
382 doesn't run the garbage collector at the same spot and then
383 shares the mem_attr with the equivalent entry. */
384 if (DECL_BUILT_IN_CLASS (t) == BUILT_IN_NORMAL)
386 tree t2 = builtin_decl_explicit (DECL_FUNCTION_CODE (t));
387 if (t2)
388 t = t2;
391 set_mem_expr (funmem, t);
393 else if (fntree)
394 set_mem_expr (funmem, build_simple_mem_ref (CALL_EXPR_FN (fntree)));
396 if (ecf_flags & ECF_SIBCALL)
398 if (valreg)
399 pat = targetm.gen_sibcall_value (valreg, funmem,
400 rounded_stack_size_rtx,
401 next_arg_reg, NULL_RTX);
402 else
403 pat = targetm.gen_sibcall (funmem, rounded_stack_size_rtx,
404 next_arg_reg, GEN_INT (struct_value_size));
406 /* If the target has "call" or "call_value" insns, then prefer them
407 if no arguments are actually popped. If the target does not have
408 "call" or "call_value" insns, then we must use the popping versions
409 even if the call has no arguments to pop. */
410 else if (n_popped > 0
411 || !(valreg
412 ? targetm.have_call_value ()
413 : targetm.have_call ()))
415 rtx n_pop = GEN_INT (n_popped);
417 /* If this subroutine pops its own args, record that in the call insn
418 if possible, for the sake of frame pointer elimination. */
420 if (valreg)
421 pat = targetm.gen_call_value_pop (valreg, funmem,
422 rounded_stack_size_rtx,
423 next_arg_reg, n_pop);
424 else
425 pat = targetm.gen_call_pop (funmem, rounded_stack_size_rtx,
426 next_arg_reg, n_pop);
428 already_popped = 1;
430 else
432 if (valreg)
433 pat = targetm.gen_call_value (valreg, funmem, rounded_stack_size_rtx,
434 next_arg_reg, NULL_RTX);
435 else
436 pat = targetm.gen_call (funmem, rounded_stack_size_rtx, next_arg_reg,
437 GEN_INT (struct_value_size));
439 emit_insn (pat);
441 /* Find the call we just emitted. */
442 rtx_call_insn *call_insn = last_call_insn ();
444 /* Some target create a fresh MEM instead of reusing the one provided
445 above. Set its MEM_EXPR. */
446 call = get_call_rtx_from (call_insn);
447 if (call
448 && MEM_EXPR (XEXP (call, 0)) == NULL_TREE
449 && MEM_EXPR (funmem) != NULL_TREE)
450 set_mem_expr (XEXP (call, 0), MEM_EXPR (funmem));
452 /* Mark instrumented calls. */
453 if (call && fntree)
454 CALL_EXPR_WITH_BOUNDS_P (call) = CALL_WITH_BOUNDS_P (fntree);
456 /* Put the register usage information there. */
457 add_function_usage_to (call_insn, call_fusage);
459 /* If this is a const call, then set the insn's unchanging bit. */
460 if (ecf_flags & ECF_CONST)
461 RTL_CONST_CALL_P (call_insn) = 1;
463 /* If this is a pure call, then set the insn's unchanging bit. */
464 if (ecf_flags & ECF_PURE)
465 RTL_PURE_CALL_P (call_insn) = 1;
467 /* If this is a const call, then set the insn's unchanging bit. */
468 if (ecf_flags & ECF_LOOPING_CONST_OR_PURE)
469 RTL_LOOPING_CONST_OR_PURE_CALL_P (call_insn) = 1;
471 /* Create a nothrow REG_EH_REGION note, if needed. */
472 make_reg_eh_region_note (call_insn, ecf_flags, 0);
474 if (ecf_flags & ECF_NORETURN)
475 add_reg_note (call_insn, REG_NORETURN, const0_rtx);
477 if (ecf_flags & ECF_RETURNS_TWICE)
479 add_reg_note (call_insn, REG_SETJMP, const0_rtx);
480 cfun->calls_setjmp = 1;
483 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
485 /* Restore this now, so that we do defer pops for this call's args
486 if the context of the call as a whole permits. */
487 inhibit_defer_pop = old_inhibit_defer_pop;
489 if (n_popped > 0)
491 if (!already_popped)
492 CALL_INSN_FUNCTION_USAGE (call_insn)
493 = gen_rtx_EXPR_LIST (VOIDmode,
494 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
495 CALL_INSN_FUNCTION_USAGE (call_insn));
496 rounded_stack_size -= n_popped;
497 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
498 stack_pointer_delta -= n_popped;
500 add_reg_note (call_insn, REG_ARGS_SIZE, GEN_INT (stack_pointer_delta));
502 /* If popup is needed, stack realign must use DRAP */
503 if (SUPPORTS_STACK_ALIGNMENT)
504 crtl->need_drap = true;
506 /* For noreturn calls when not accumulating outgoing args force
507 REG_ARGS_SIZE note to prevent crossjumping of calls with different
508 args sizes. */
509 else if (!ACCUMULATE_OUTGOING_ARGS && (ecf_flags & ECF_NORETURN) != 0)
510 add_reg_note (call_insn, REG_ARGS_SIZE, GEN_INT (stack_pointer_delta));
512 if (!ACCUMULATE_OUTGOING_ARGS)
514 /* If returning from the subroutine does not automatically pop the args,
515 we need an instruction to pop them sooner or later.
516 Perhaps do it now; perhaps just record how much space to pop later.
518 If returning from the subroutine does pop the args, indicate that the
519 stack pointer will be changed. */
521 if (rounded_stack_size != 0)
523 if (ecf_flags & ECF_NORETURN)
524 /* Just pretend we did the pop. */
525 stack_pointer_delta -= rounded_stack_size;
526 else if (flag_defer_pop && inhibit_defer_pop == 0
527 && ! (ecf_flags & (ECF_CONST | ECF_PURE)))
528 pending_stack_adjust += rounded_stack_size;
529 else
530 adjust_stack (rounded_stack_size_rtx);
533 /* When we accumulate outgoing args, we must avoid any stack manipulations.
534 Restore the stack pointer to its original value now. Usually
535 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
536 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
537 popping variants of functions exist as well.
539 ??? We may optimize similar to defer_pop above, but it is
540 probably not worthwhile.
542 ??? It will be worthwhile to enable combine_stack_adjustments even for
543 such machines. */
544 else if (n_popped)
545 anti_adjust_stack (GEN_INT (n_popped));
548 /* Determine if the function identified by FNDECL is one with
549 special properties we wish to know about. Modify FLAGS accordingly.
551 For example, if the function might return more than one time (setjmp), then
552 set ECF_RETURNS_TWICE.
554 Set ECF_MAY_BE_ALLOCA for any memory allocation function that might allocate
555 space from the stack such as alloca. */
557 static int
558 special_function_p (const_tree fndecl, int flags)
560 tree name_decl = DECL_NAME (fndecl);
562 /* For instrumentation clones we want to derive flags
563 from the original name. */
564 if (cgraph_node::get (fndecl)
565 && cgraph_node::get (fndecl)->instrumentation_clone)
566 name_decl = DECL_NAME (cgraph_node::get (fndecl)->orig_decl);
568 if (fndecl && name_decl
569 && IDENTIFIER_LENGTH (name_decl) <= 11
570 /* Exclude functions not at the file scope, or not `extern',
571 since they are not the magic functions we would otherwise
572 think they are.
573 FIXME: this should be handled with attributes, not with this
574 hacky imitation of DECL_ASSEMBLER_NAME. It's (also) wrong
575 because you can declare fork() inside a function if you
576 wish. */
577 && (DECL_CONTEXT (fndecl) == NULL_TREE
578 || TREE_CODE (DECL_CONTEXT (fndecl)) == TRANSLATION_UNIT_DECL)
579 && TREE_PUBLIC (fndecl))
581 const char *name = IDENTIFIER_POINTER (name_decl);
582 const char *tname = name;
584 /* We assume that alloca will always be called by name. It
585 makes no sense to pass it as a pointer-to-function to
586 anything that does not understand its behavior. */
587 if (IDENTIFIER_LENGTH (name_decl) == 6
588 && name[0] == 'a'
589 && ! strcmp (name, "alloca"))
590 flags |= ECF_MAY_BE_ALLOCA;
592 /* Disregard prefix _ or __. */
593 if (name[0] == '_')
595 if (name[1] == '_')
596 tname += 2;
597 else
598 tname += 1;
601 /* ECF_RETURNS_TWICE is safe even for -ffreestanding. */
602 if (! strcmp (tname, "setjmp")
603 || ! strcmp (tname, "sigsetjmp")
604 || ! strcmp (name, "savectx")
605 || ! strcmp (name, "vfork")
606 || ! strcmp (name, "getcontext"))
607 flags |= ECF_RETURNS_TWICE;
610 if (DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
611 switch (DECL_FUNCTION_CODE (fndecl))
613 case BUILT_IN_ALLOCA:
614 case BUILT_IN_ALLOCA_WITH_ALIGN:
615 flags |= ECF_MAY_BE_ALLOCA;
616 break;
617 default:
618 break;
621 return flags;
624 /* Similar to special_function_p; return a set of ERF_ flags for the
625 function FNDECL. */
626 static int
627 decl_return_flags (tree fndecl)
629 tree attr;
630 tree type = TREE_TYPE (fndecl);
631 if (!type)
632 return 0;
634 attr = lookup_attribute ("fn spec", TYPE_ATTRIBUTES (type));
635 if (!attr)
636 return 0;
638 attr = TREE_VALUE (TREE_VALUE (attr));
639 if (!attr || TREE_STRING_LENGTH (attr) < 1)
640 return 0;
642 switch (TREE_STRING_POINTER (attr)[0])
644 case '1':
645 case '2':
646 case '3':
647 case '4':
648 return ERF_RETURNS_ARG | (TREE_STRING_POINTER (attr)[0] - '1');
650 case 'm':
651 return ERF_NOALIAS;
653 case '.':
654 default:
655 return 0;
659 /* Return nonzero when FNDECL represents a call to setjmp. */
662 setjmp_call_p (const_tree fndecl)
664 if (DECL_IS_RETURNS_TWICE (fndecl))
665 return ECF_RETURNS_TWICE;
666 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
670 /* Return true if STMT may be an alloca call. */
672 bool
673 gimple_maybe_alloca_call_p (const gimple *stmt)
675 tree fndecl;
677 if (!is_gimple_call (stmt))
678 return false;
680 fndecl = gimple_call_fndecl (stmt);
681 if (fndecl && (special_function_p (fndecl, 0) & ECF_MAY_BE_ALLOCA))
682 return true;
684 return false;
687 /* Return true if STMT is a builtin alloca call. */
689 bool
690 gimple_alloca_call_p (const gimple *stmt)
692 tree fndecl;
694 if (!is_gimple_call (stmt))
695 return false;
697 fndecl = gimple_call_fndecl (stmt);
698 if (fndecl && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
699 switch (DECL_FUNCTION_CODE (fndecl))
701 case BUILT_IN_ALLOCA:
702 case BUILT_IN_ALLOCA_WITH_ALIGN:
703 return true;
704 default:
705 break;
708 return false;
711 /* Return true when exp contains a builtin alloca call. */
713 bool
714 alloca_call_p (const_tree exp)
716 tree fndecl;
717 if (TREE_CODE (exp) == CALL_EXPR
718 && (fndecl = get_callee_fndecl (exp))
719 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
720 switch (DECL_FUNCTION_CODE (fndecl))
722 case BUILT_IN_ALLOCA:
723 case BUILT_IN_ALLOCA_WITH_ALIGN:
724 return true;
725 default:
726 break;
729 return false;
732 /* Return TRUE if FNDECL is either a TM builtin or a TM cloned
733 function. Return FALSE otherwise. */
735 static bool
736 is_tm_builtin (const_tree fndecl)
738 if (fndecl == NULL)
739 return false;
741 if (decl_is_tm_clone (fndecl))
742 return true;
744 if (DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
746 switch (DECL_FUNCTION_CODE (fndecl))
748 case BUILT_IN_TM_COMMIT:
749 case BUILT_IN_TM_COMMIT_EH:
750 case BUILT_IN_TM_ABORT:
751 case BUILT_IN_TM_IRREVOCABLE:
752 case BUILT_IN_TM_GETTMCLONE_IRR:
753 case BUILT_IN_TM_MEMCPY:
754 case BUILT_IN_TM_MEMMOVE:
755 case BUILT_IN_TM_MEMSET:
756 CASE_BUILT_IN_TM_STORE (1):
757 CASE_BUILT_IN_TM_STORE (2):
758 CASE_BUILT_IN_TM_STORE (4):
759 CASE_BUILT_IN_TM_STORE (8):
760 CASE_BUILT_IN_TM_STORE (FLOAT):
761 CASE_BUILT_IN_TM_STORE (DOUBLE):
762 CASE_BUILT_IN_TM_STORE (LDOUBLE):
763 CASE_BUILT_IN_TM_STORE (M64):
764 CASE_BUILT_IN_TM_STORE (M128):
765 CASE_BUILT_IN_TM_STORE (M256):
766 CASE_BUILT_IN_TM_LOAD (1):
767 CASE_BUILT_IN_TM_LOAD (2):
768 CASE_BUILT_IN_TM_LOAD (4):
769 CASE_BUILT_IN_TM_LOAD (8):
770 CASE_BUILT_IN_TM_LOAD (FLOAT):
771 CASE_BUILT_IN_TM_LOAD (DOUBLE):
772 CASE_BUILT_IN_TM_LOAD (LDOUBLE):
773 CASE_BUILT_IN_TM_LOAD (M64):
774 CASE_BUILT_IN_TM_LOAD (M128):
775 CASE_BUILT_IN_TM_LOAD (M256):
776 case BUILT_IN_TM_LOG:
777 case BUILT_IN_TM_LOG_1:
778 case BUILT_IN_TM_LOG_2:
779 case BUILT_IN_TM_LOG_4:
780 case BUILT_IN_TM_LOG_8:
781 case BUILT_IN_TM_LOG_FLOAT:
782 case BUILT_IN_TM_LOG_DOUBLE:
783 case BUILT_IN_TM_LOG_LDOUBLE:
784 case BUILT_IN_TM_LOG_M64:
785 case BUILT_IN_TM_LOG_M128:
786 case BUILT_IN_TM_LOG_M256:
787 return true;
788 default:
789 break;
792 return false;
795 /* Detect flags (function attributes) from the function decl or type node. */
798 flags_from_decl_or_type (const_tree exp)
800 int flags = 0;
802 if (DECL_P (exp))
804 /* The function exp may have the `malloc' attribute. */
805 if (DECL_IS_MALLOC (exp))
806 flags |= ECF_MALLOC;
808 /* The function exp may have the `returns_twice' attribute. */
809 if (DECL_IS_RETURNS_TWICE (exp))
810 flags |= ECF_RETURNS_TWICE;
812 /* Process the pure and const attributes. */
813 if (TREE_READONLY (exp))
814 flags |= ECF_CONST;
815 if (DECL_PURE_P (exp))
816 flags |= ECF_PURE;
817 if (DECL_LOOPING_CONST_OR_PURE_P (exp))
818 flags |= ECF_LOOPING_CONST_OR_PURE;
820 if (DECL_IS_NOVOPS (exp))
821 flags |= ECF_NOVOPS;
822 if (lookup_attribute ("leaf", DECL_ATTRIBUTES (exp)))
823 flags |= ECF_LEAF;
824 if (lookup_attribute ("cold", DECL_ATTRIBUTES (exp)))
825 flags |= ECF_COLD;
827 if (TREE_NOTHROW (exp))
828 flags |= ECF_NOTHROW;
830 if (flag_tm)
832 if (is_tm_builtin (exp))
833 flags |= ECF_TM_BUILTIN;
834 else if ((flags & (ECF_CONST|ECF_NOVOPS)) != 0
835 || lookup_attribute ("transaction_pure",
836 TYPE_ATTRIBUTES (TREE_TYPE (exp))))
837 flags |= ECF_TM_PURE;
840 flags = special_function_p (exp, flags);
842 else if (TYPE_P (exp))
844 if (TYPE_READONLY (exp))
845 flags |= ECF_CONST;
847 if (flag_tm
848 && ((flags & ECF_CONST) != 0
849 || lookup_attribute ("transaction_pure", TYPE_ATTRIBUTES (exp))))
850 flags |= ECF_TM_PURE;
852 else
853 gcc_unreachable ();
855 if (TREE_THIS_VOLATILE (exp))
857 flags |= ECF_NORETURN;
858 if (flags & (ECF_CONST|ECF_PURE))
859 flags |= ECF_LOOPING_CONST_OR_PURE;
862 return flags;
865 /* Detect flags from a CALL_EXPR. */
868 call_expr_flags (const_tree t)
870 int flags;
871 tree decl = get_callee_fndecl (t);
873 if (decl)
874 flags = flags_from_decl_or_type (decl);
875 else if (CALL_EXPR_FN (t) == NULL_TREE)
876 flags = internal_fn_flags (CALL_EXPR_IFN (t));
877 else
879 tree type = TREE_TYPE (CALL_EXPR_FN (t));
880 if (type && TREE_CODE (type) == POINTER_TYPE)
881 flags = flags_from_decl_or_type (TREE_TYPE (type));
882 else
883 flags = 0;
884 if (CALL_EXPR_BY_DESCRIPTOR (t))
885 flags |= ECF_BY_DESCRIPTOR;
888 return flags;
891 /* Return true if TYPE should be passed by invisible reference. */
893 bool
894 pass_by_reference (CUMULATIVE_ARGS *ca, machine_mode mode,
895 tree type, bool named_arg)
897 if (type)
899 /* If this type contains non-trivial constructors, then it is
900 forbidden for the middle-end to create any new copies. */
901 if (TREE_ADDRESSABLE (type))
902 return true;
904 /* GCC post 3.4 passes *all* variable sized types by reference. */
905 if (!TYPE_SIZE (type) || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
906 return true;
908 /* If a record type should be passed the same as its first (and only)
909 member, use the type and mode of that member. */
910 if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
912 type = TREE_TYPE (first_field (type));
913 mode = TYPE_MODE (type);
917 return targetm.calls.pass_by_reference (pack_cumulative_args (ca), mode,
918 type, named_arg);
921 /* Return true if TYPE, which is passed by reference, should be callee
922 copied instead of caller copied. */
924 bool
925 reference_callee_copied (CUMULATIVE_ARGS *ca, machine_mode mode,
926 tree type, bool named_arg)
928 if (type && TREE_ADDRESSABLE (type))
929 return false;
930 return targetm.calls.callee_copies (pack_cumulative_args (ca), mode, type,
931 named_arg);
935 /* Precompute all register parameters as described by ARGS, storing values
936 into fields within the ARGS array.
938 NUM_ACTUALS indicates the total number elements in the ARGS array.
940 Set REG_PARM_SEEN if we encounter a register parameter. */
942 static void
943 precompute_register_parameters (int num_actuals, struct arg_data *args,
944 int *reg_parm_seen)
946 int i;
948 *reg_parm_seen = 0;
950 for (i = 0; i < num_actuals; i++)
951 if (args[i].reg != 0 && ! args[i].pass_on_stack)
953 *reg_parm_seen = 1;
955 if (args[i].value == 0)
957 push_temp_slots ();
958 args[i].value = expand_normal (args[i].tree_value);
959 preserve_temp_slots (args[i].value);
960 pop_temp_slots ();
963 /* If we are to promote the function arg to a wider mode,
964 do it now. */
966 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
967 args[i].value
968 = convert_modes (args[i].mode,
969 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
970 args[i].value, args[i].unsignedp);
972 /* If the value is a non-legitimate constant, force it into a
973 pseudo now. TLS symbols sometimes need a call to resolve. */
974 if (CONSTANT_P (args[i].value)
975 && !targetm.legitimate_constant_p (args[i].mode, args[i].value))
976 args[i].value = force_reg (args[i].mode, args[i].value);
978 /* If we're going to have to load the value by parts, pull the
979 parts into pseudos. The part extraction process can involve
980 non-trivial computation. */
981 if (GET_CODE (args[i].reg) == PARALLEL)
983 tree type = TREE_TYPE (args[i].tree_value);
984 args[i].parallel_value
985 = emit_group_load_into_temps (args[i].reg, args[i].value,
986 type, int_size_in_bytes (type));
989 /* If the value is expensive, and we are inside an appropriately
990 short loop, put the value into a pseudo and then put the pseudo
991 into the hard reg.
993 For small register classes, also do this if this call uses
994 register parameters. This is to avoid reload conflicts while
995 loading the parameters registers. */
997 else if ((! (REG_P (args[i].value)
998 || (GET_CODE (args[i].value) == SUBREG
999 && REG_P (SUBREG_REG (args[i].value)))))
1000 && args[i].mode != BLKmode
1001 && (set_src_cost (args[i].value, args[i].mode,
1002 optimize_insn_for_speed_p ())
1003 > COSTS_N_INSNS (1))
1004 && ((*reg_parm_seen
1005 && targetm.small_register_classes_for_mode_p (args[i].mode))
1006 || optimize))
1007 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
1011 #ifdef REG_PARM_STACK_SPACE
1013 /* The argument list is the property of the called routine and it
1014 may clobber it. If the fixed area has been used for previous
1015 parameters, we must save and restore it. */
1017 static rtx
1018 save_fixed_argument_area (int reg_parm_stack_space, rtx argblock, int *low_to_save, int *high_to_save)
1020 int low;
1021 int high;
1023 /* Compute the boundary of the area that needs to be saved, if any. */
1024 high = reg_parm_stack_space;
1025 if (ARGS_GROW_DOWNWARD)
1026 high += 1;
1028 if (high > highest_outgoing_arg_in_use)
1029 high = highest_outgoing_arg_in_use;
1031 for (low = 0; low < high; low++)
1032 if (stack_usage_map[low] != 0)
1034 int num_to_save;
1035 machine_mode save_mode;
1036 int delta;
1037 rtx addr;
1038 rtx stack_area;
1039 rtx save_area;
1041 while (stack_usage_map[--high] == 0)
1044 *low_to_save = low;
1045 *high_to_save = high;
1047 num_to_save = high - low + 1;
1049 /* If we don't have the required alignment, must do this
1050 in BLKmode. */
1051 scalar_int_mode imode;
1052 if (int_mode_for_size (num_to_save * BITS_PER_UNIT, 1).exists (&imode)
1053 && (low & (MIN (GET_MODE_SIZE (imode),
1054 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)) == 0)
1055 save_mode = imode;
1056 else
1057 save_mode = BLKmode;
1059 if (ARGS_GROW_DOWNWARD)
1060 delta = -high;
1061 else
1062 delta = low;
1064 addr = plus_constant (Pmode, argblock, delta);
1065 stack_area = gen_rtx_MEM (save_mode, memory_address (save_mode, addr));
1067 set_mem_align (stack_area, PARM_BOUNDARY);
1068 if (save_mode == BLKmode)
1070 save_area = assign_stack_temp (BLKmode, num_to_save);
1071 emit_block_move (validize_mem (save_area), stack_area,
1072 GEN_INT (num_to_save), BLOCK_OP_CALL_PARM);
1074 else
1076 save_area = gen_reg_rtx (save_mode);
1077 emit_move_insn (save_area, stack_area);
1080 return save_area;
1083 return NULL_RTX;
1086 static void
1087 restore_fixed_argument_area (rtx save_area, rtx argblock, int high_to_save, int low_to_save)
1089 machine_mode save_mode = GET_MODE (save_area);
1090 int delta;
1091 rtx addr, stack_area;
1093 if (ARGS_GROW_DOWNWARD)
1094 delta = -high_to_save;
1095 else
1096 delta = low_to_save;
1098 addr = plus_constant (Pmode, argblock, delta);
1099 stack_area = gen_rtx_MEM (save_mode, memory_address (save_mode, addr));
1100 set_mem_align (stack_area, PARM_BOUNDARY);
1102 if (save_mode != BLKmode)
1103 emit_move_insn (stack_area, save_area);
1104 else
1105 emit_block_move (stack_area, validize_mem (save_area),
1106 GEN_INT (high_to_save - low_to_save + 1),
1107 BLOCK_OP_CALL_PARM);
1109 #endif /* REG_PARM_STACK_SPACE */
1111 /* If any elements in ARGS refer to parameters that are to be passed in
1112 registers, but not in memory, and whose alignment does not permit a
1113 direct copy into registers. Copy the values into a group of pseudos
1114 which we will later copy into the appropriate hard registers.
1116 Pseudos for each unaligned argument will be stored into the array
1117 args[argnum].aligned_regs. The caller is responsible for deallocating
1118 the aligned_regs array if it is nonzero. */
1120 static void
1121 store_unaligned_arguments_into_pseudos (struct arg_data *args, int num_actuals)
1123 int i, j;
1125 for (i = 0; i < num_actuals; i++)
1126 if (args[i].reg != 0 && ! args[i].pass_on_stack
1127 && GET_CODE (args[i].reg) != PARALLEL
1128 && args[i].mode == BLKmode
1129 && MEM_P (args[i].value)
1130 && (MEM_ALIGN (args[i].value)
1131 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1133 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1134 int endian_correction = 0;
1136 if (args[i].partial)
1138 gcc_assert (args[i].partial % UNITS_PER_WORD == 0);
1139 args[i].n_aligned_regs = args[i].partial / UNITS_PER_WORD;
1141 else
1143 args[i].n_aligned_regs
1144 = (bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
1147 args[i].aligned_regs = XNEWVEC (rtx, args[i].n_aligned_regs);
1149 /* Structures smaller than a word are normally aligned to the
1150 least significant byte. On a BYTES_BIG_ENDIAN machine,
1151 this means we must skip the empty high order bytes when
1152 calculating the bit offset. */
1153 if (bytes < UNITS_PER_WORD
1154 #ifdef BLOCK_REG_PADDING
1155 && (BLOCK_REG_PADDING (args[i].mode,
1156 TREE_TYPE (args[i].tree_value), 1)
1157 == PAD_DOWNWARD)
1158 #else
1159 && BYTES_BIG_ENDIAN
1160 #endif
1162 endian_correction = BITS_PER_WORD - bytes * BITS_PER_UNIT;
1164 for (j = 0; j < args[i].n_aligned_regs; j++)
1166 rtx reg = gen_reg_rtx (word_mode);
1167 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1168 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
1170 args[i].aligned_regs[j] = reg;
1171 word = extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
1172 word_mode, word_mode, false, NULL);
1174 /* There is no need to restrict this code to loading items
1175 in TYPE_ALIGN sized hunks. The bitfield instructions can
1176 load up entire word sized registers efficiently.
1178 ??? This may not be needed anymore.
1179 We use to emit a clobber here but that doesn't let later
1180 passes optimize the instructions we emit. By storing 0 into
1181 the register later passes know the first AND to zero out the
1182 bitfield being set in the register is unnecessary. The store
1183 of 0 will be deleted as will at least the first AND. */
1185 emit_move_insn (reg, const0_rtx);
1187 bytes -= bitsize / BITS_PER_UNIT;
1188 store_bit_field (reg, bitsize, endian_correction, 0, 0,
1189 word_mode, word, false);
1194 /* The limit set by -Walloc-larger-than=. */
1195 static GTY(()) tree alloc_object_size_limit;
1197 /* Initialize ALLOC_OBJECT_SIZE_LIMIT based on the -Walloc-size-larger-than=
1198 setting if the option is specified, or to the maximum object size if it
1199 is not. Return the initialized value. */
1201 static tree
1202 alloc_max_size (void)
1204 if (!alloc_object_size_limit)
1206 alloc_object_size_limit = TYPE_MAX_VALUE (ssizetype);
1208 if (warn_alloc_size_limit)
1210 char *end = NULL;
1211 errno = 0;
1212 unsigned HOST_WIDE_INT unit = 1;
1213 unsigned HOST_WIDE_INT limit
1214 = strtoull (warn_alloc_size_limit, &end, 10);
1216 if (!errno)
1218 if (end && *end)
1220 /* Numeric option arguments are at most INT_MAX. Make it
1221 possible to specify a larger value by accepting common
1222 suffixes. */
1223 if (!strcmp (end, "kB"))
1224 unit = 1000;
1225 else if (!strcasecmp (end, "KiB") || strcmp (end, "KB"))
1226 unit = 1024;
1227 else if (!strcmp (end, "MB"))
1228 unit = HOST_WIDE_INT_UC (1000) * 1000;
1229 else if (!strcasecmp (end, "MiB"))
1230 unit = HOST_WIDE_INT_UC (1024) * 1024;
1231 else if (!strcasecmp (end, "GB"))
1232 unit = HOST_WIDE_INT_UC (1000) * 1000 * 1000;
1233 else if (!strcasecmp (end, "GiB"))
1234 unit = HOST_WIDE_INT_UC (1024) * 1024 * 1024;
1235 else if (!strcasecmp (end, "TB"))
1236 unit = HOST_WIDE_INT_UC (1000) * 1000 * 1000 * 1000;
1237 else if (!strcasecmp (end, "TiB"))
1238 unit = HOST_WIDE_INT_UC (1024) * 1024 * 1024 * 1024;
1239 else if (!strcasecmp (end, "PB"))
1240 unit = HOST_WIDE_INT_UC (1000) * 1000 * 1000 * 1000 * 1000;
1241 else if (!strcasecmp (end, "PiB"))
1242 unit = HOST_WIDE_INT_UC (1024) * 1024 * 1024 * 1024 * 1024;
1243 else if (!strcasecmp (end, "EB"))
1244 unit = HOST_WIDE_INT_UC (1000) * 1000 * 1000 * 1000 * 1000
1245 * 1000;
1246 else if (!strcasecmp (end, "EiB"))
1247 unit = HOST_WIDE_INT_UC (1024) * 1024 * 1024 * 1024 * 1024
1248 * 1024;
1249 else
1250 unit = 0;
1253 if (unit)
1255 widest_int w = wi::mul (limit, unit);
1256 if (w < wi::to_widest (alloc_object_size_limit))
1257 alloc_object_size_limit = wide_int_to_tree (ssizetype, w);
1262 return alloc_object_size_limit;
1265 /* Return true when EXP's range can be determined and set RANGE[] to it
1266 after adjusting it if necessary to make EXP a valid size argument to
1267 an allocation function declared with attribute alloc_size (whose
1268 argument may be signed), or to a string manipulation function like
1269 memset. */
1271 bool
1272 get_size_range (tree exp, tree range[2])
1274 if (tree_fits_uhwi_p (exp))
1276 /* EXP is a constant. */
1277 range[0] = range[1] = exp;
1278 return true;
1281 wide_int min, max;
1282 enum value_range_type range_type
1283 = ((TREE_CODE (exp) == SSA_NAME && INTEGRAL_TYPE_P (TREE_TYPE (exp)))
1284 ? get_range_info (exp, &min, &max) : VR_VARYING);
1286 if (range_type == VR_VARYING)
1288 /* No range information available. */
1289 range[0] = NULL_TREE;
1290 range[1] = NULL_TREE;
1291 return false;
1294 tree exptype = TREE_TYPE (exp);
1295 unsigned expprec = TYPE_PRECISION (exptype);
1297 bool signed_p = !TYPE_UNSIGNED (exptype);
1299 if (range_type == VR_ANTI_RANGE)
1301 if (signed_p)
1303 if (wi::les_p (max, 0))
1305 /* EXP is not in a strictly negative range. That means
1306 it must be in some (not necessarily strictly) positive
1307 range which includes zero. Since in signed to unsigned
1308 conversions negative values end up converted to large
1309 positive values, and otherwise they are not valid sizes,
1310 the resulting range is in both cases [0, TYPE_MAX]. */
1311 min = wi::zero (expprec);
1312 max = wi::to_wide (TYPE_MAX_VALUE (exptype));
1314 else if (wi::les_p (min - 1, 0))
1316 /* EXP is not in a negative-positive range. That means EXP
1317 is either negative, or greater than max. Since negative
1318 sizes are invalid make the range [MAX + 1, TYPE_MAX]. */
1319 min = max + 1;
1320 max = wi::to_wide (TYPE_MAX_VALUE (exptype));
1322 else
1324 max = min - 1;
1325 min = wi::zero (expprec);
1328 else if (wi::eq_p (0, min - 1))
1330 /* EXP is unsigned and not in the range [1, MAX]. That means
1331 it's either zero or greater than MAX. Even though 0 would
1332 normally be detected by -Walloc-zero set the range to
1333 [MAX, TYPE_MAX] so that when MAX is greater than the limit
1334 the whole range is diagnosed. */
1335 min = max + 1;
1336 max = wi::to_wide (TYPE_MAX_VALUE (exptype));
1338 else
1340 max = min - 1;
1341 min = wi::zero (expprec);
1345 range[0] = wide_int_to_tree (exptype, min);
1346 range[1] = wide_int_to_tree (exptype, max);
1348 return true;
1351 /* Diagnose a call EXP to function FN decorated with attribute alloc_size
1352 whose argument numbers given by IDX with values given by ARGS exceed
1353 the maximum object size or cause an unsigned oveflow (wrapping) when
1354 multiplied. When ARGS[0] is null the function does nothing. ARGS[1]
1355 may be null for functions like malloc, and non-null for those like
1356 calloc that are decorated with a two-argument attribute alloc_size. */
1358 void
1359 maybe_warn_alloc_args_overflow (tree fn, tree exp, tree args[2], int idx[2])
1361 /* The range each of the (up to) two arguments is known to be in. */
1362 tree argrange[2][2] = { { NULL_TREE, NULL_TREE }, { NULL_TREE, NULL_TREE } };
1364 /* Maximum object size set by -Walloc-size-larger-than= or SIZE_MAX / 2. */
1365 tree maxobjsize = alloc_max_size ();
1367 location_t loc = EXPR_LOCATION (exp);
1369 bool warned = false;
1371 /* Validate each argument individually. */
1372 for (unsigned i = 0; i != 2 && args[i]; ++i)
1374 if (TREE_CODE (args[i]) == INTEGER_CST)
1376 argrange[i][0] = args[i];
1377 argrange[i][1] = args[i];
1379 if (tree_int_cst_lt (args[i], integer_zero_node))
1381 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1382 "%Kargument %i value %qE is negative",
1383 exp, idx[i] + 1, args[i]);
1385 else if (integer_zerop (args[i]))
1387 /* Avoid issuing -Walloc-zero for allocation functions other
1388 than __builtin_alloca that are declared with attribute
1389 returns_nonnull because there's no portability risk. This
1390 avoids warning for such calls to libiberty's xmalloc and
1391 friends.
1392 Also avoid issuing the warning for calls to function named
1393 "alloca". */
1394 if ((DECL_FUNCTION_CODE (fn) == BUILT_IN_ALLOCA
1395 && IDENTIFIER_LENGTH (DECL_NAME (fn)) != 6)
1396 || (DECL_FUNCTION_CODE (fn) != BUILT_IN_ALLOCA
1397 && !lookup_attribute ("returns_nonnull",
1398 TYPE_ATTRIBUTES (TREE_TYPE (fn)))))
1399 warned = warning_at (loc, OPT_Walloc_zero,
1400 "%Kargument %i value is zero",
1401 exp, idx[i] + 1);
1403 else if (tree_int_cst_lt (maxobjsize, args[i]))
1405 /* G++ emits calls to ::operator new[](SIZE_MAX) in C++98
1406 mode and with -fno-exceptions as a way to indicate array
1407 size overflow. There's no good way to detect C++98 here
1408 so avoid diagnosing these calls for all C++ modes. */
1409 if (i == 0
1410 && !args[1]
1411 && lang_GNU_CXX ()
1412 && DECL_IS_OPERATOR_NEW (fn)
1413 && integer_all_onesp (args[i]))
1414 continue;
1416 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1417 "%Kargument %i value %qE exceeds "
1418 "maximum object size %E",
1419 exp, idx[i] + 1, args[i], maxobjsize);
1422 else if (TREE_CODE (args[i]) == SSA_NAME
1423 && get_size_range (args[i], argrange[i]))
1425 /* Verify that the argument's range is not negative (including
1426 upper bound of zero). */
1427 if (tree_int_cst_lt (argrange[i][0], integer_zero_node)
1428 && tree_int_cst_le (argrange[i][1], integer_zero_node))
1430 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1431 "%Kargument %i range [%E, %E] is negative",
1432 exp, idx[i] + 1,
1433 argrange[i][0], argrange[i][1]);
1435 else if (tree_int_cst_lt (maxobjsize, argrange[i][0]))
1437 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1438 "%Kargument %i range [%E, %E] exceeds "
1439 "maximum object size %E",
1440 exp, idx[i] + 1,
1441 argrange[i][0], argrange[i][1],
1442 maxobjsize);
1447 if (!argrange[0])
1448 return;
1450 /* For a two-argument alloc_size, validate the product of the two
1451 arguments if both of their values or ranges are known. */
1452 if (!warned && tree_fits_uhwi_p (argrange[0][0])
1453 && argrange[1][0] && tree_fits_uhwi_p (argrange[1][0])
1454 && !integer_onep (argrange[0][0])
1455 && !integer_onep (argrange[1][0]))
1457 /* Check for overflow in the product of a function decorated with
1458 attribute alloc_size (X, Y). */
1459 unsigned szprec = TYPE_PRECISION (size_type_node);
1460 wide_int x = wi::to_wide (argrange[0][0], szprec);
1461 wide_int y = wi::to_wide (argrange[1][0], szprec);
1463 bool vflow;
1464 wide_int prod = wi::umul (x, y, &vflow);
1466 if (vflow)
1467 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1468 "%Kproduct %<%E * %E%> of arguments %i and %i "
1469 "exceeds %<SIZE_MAX%>",
1470 exp, argrange[0][0], argrange[1][0],
1471 idx[0] + 1, idx[1] + 1);
1472 else if (wi::ltu_p (wi::to_wide (maxobjsize, szprec), prod))
1473 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1474 "%Kproduct %<%E * %E%> of arguments %i and %i "
1475 "exceeds maximum object size %E",
1476 exp, argrange[0][0], argrange[1][0],
1477 idx[0] + 1, idx[1] + 1,
1478 maxobjsize);
1480 if (warned)
1482 /* Print the full range of each of the two arguments to make
1483 it clear when it is, in fact, in a range and not constant. */
1484 if (argrange[0][0] != argrange [0][1])
1485 inform (loc, "argument %i in the range [%E, %E]",
1486 idx[0] + 1, argrange[0][0], argrange[0][1]);
1487 if (argrange[1][0] != argrange [1][1])
1488 inform (loc, "argument %i in the range [%E, %E]",
1489 idx[1] + 1, argrange[1][0], argrange[1][1]);
1493 if (warned)
1495 location_t fnloc = DECL_SOURCE_LOCATION (fn);
1497 if (DECL_IS_BUILTIN (fn))
1498 inform (loc,
1499 "in a call to built-in allocation function %qD", fn);
1500 else
1501 inform (fnloc,
1502 "in a call to allocation function %qD declared here", fn);
1506 /* Issue an error if CALL_EXPR was flagged as requiring
1507 tall-call optimization. */
1509 static void
1510 maybe_complain_about_tail_call (tree call_expr, const char *reason)
1512 gcc_assert (TREE_CODE (call_expr) == CALL_EXPR);
1513 if (!CALL_EXPR_MUST_TAIL_CALL (call_expr))
1514 return;
1516 error_at (EXPR_LOCATION (call_expr), "cannot tail-call: %s", reason);
1519 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1520 CALL_EXPR EXP.
1522 NUM_ACTUALS is the total number of parameters.
1524 N_NAMED_ARGS is the total number of named arguments.
1526 STRUCT_VALUE_ADDR_VALUE is the implicit argument for a struct return
1527 value, or null.
1529 FNDECL is the tree code for the target of this call (if known)
1531 ARGS_SO_FAR holds state needed by the target to know where to place
1532 the next argument.
1534 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1535 for arguments which are passed in registers.
1537 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1538 and may be modified by this routine.
1540 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1541 flags which may be modified by this routine.
1543 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
1544 that requires allocation of stack space.
1546 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
1547 the thunked-to function. */
1549 static void
1550 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED,
1551 struct arg_data *args,
1552 struct args_size *args_size,
1553 int n_named_args ATTRIBUTE_UNUSED,
1554 tree exp, tree struct_value_addr_value,
1555 tree fndecl, tree fntype,
1556 cumulative_args_t args_so_far,
1557 int reg_parm_stack_space,
1558 rtx *old_stack_level, int *old_pending_adj,
1559 int *must_preallocate, int *ecf_flags,
1560 bool *may_tailcall, bool call_from_thunk_p)
1562 CUMULATIVE_ARGS *args_so_far_pnt = get_cumulative_args (args_so_far);
1563 location_t loc = EXPR_LOCATION (exp);
1565 /* Count arg position in order args appear. */
1566 int argpos;
1568 int i;
1570 args_size->constant = 0;
1571 args_size->var = 0;
1573 bitmap_obstack_initialize (NULL);
1575 /* In this loop, we consider args in the order they are written.
1576 We fill up ARGS from the back. */
1578 i = num_actuals - 1;
1580 int j = i, ptr_arg = -1;
1581 call_expr_arg_iterator iter;
1582 tree arg;
1583 bitmap slots = NULL;
1585 if (struct_value_addr_value)
1587 args[j].tree_value = struct_value_addr_value;
1588 j--;
1590 /* If we pass structure address then we need to
1591 create bounds for it. Since created bounds is
1592 a call statement, we expand it right here to avoid
1593 fixing all other places where it may be expanded. */
1594 if (CALL_WITH_BOUNDS_P (exp))
1596 args[j].value = gen_reg_rtx (targetm.chkp_bound_mode ());
1597 args[j].tree_value
1598 = chkp_make_bounds_for_struct_addr (struct_value_addr_value);
1599 expand_expr_real (args[j].tree_value, args[j].value, VOIDmode,
1600 EXPAND_NORMAL, 0, false);
1601 args[j].pointer_arg = j + 1;
1602 j--;
1605 argpos = 0;
1606 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
1608 tree argtype = TREE_TYPE (arg);
1610 /* Remember last param with pointer and associate it
1611 with following pointer bounds. */
1612 if (CALL_WITH_BOUNDS_P (exp)
1613 && chkp_type_has_pointer (argtype))
1615 if (slots)
1616 BITMAP_FREE (slots);
1617 ptr_arg = j;
1618 if (!BOUNDED_TYPE_P (argtype))
1620 slots = BITMAP_ALLOC (NULL);
1621 chkp_find_bound_slots (argtype, slots);
1624 else if (CALL_WITH_BOUNDS_P (exp)
1625 && pass_by_reference (NULL, TYPE_MODE (argtype), argtype,
1626 argpos < n_named_args))
1628 if (slots)
1629 BITMAP_FREE (slots);
1630 ptr_arg = j;
1632 else if (POINTER_BOUNDS_TYPE_P (argtype))
1634 /* We expect bounds in instrumented calls only.
1635 Otherwise it is a sign we lost flag due to some optimization
1636 and may emit call args incorrectly. */
1637 gcc_assert (CALL_WITH_BOUNDS_P (exp));
1639 /* For structures look for the next available pointer. */
1640 if (ptr_arg != -1 && slots)
1642 unsigned bnd_no = bitmap_first_set_bit (slots);
1643 args[j].pointer_offset =
1644 bnd_no * POINTER_SIZE / BITS_PER_UNIT;
1646 bitmap_clear_bit (slots, bnd_no);
1648 /* Check we have no more pointers in the structure. */
1649 if (bitmap_empty_p (slots))
1650 BITMAP_FREE (slots);
1652 args[j].pointer_arg = ptr_arg;
1654 /* Check we covered all pointers in the previous
1655 non bounds arg. */
1656 if (!slots)
1657 ptr_arg = -1;
1659 else
1660 ptr_arg = -1;
1662 if (targetm.calls.split_complex_arg
1663 && argtype
1664 && TREE_CODE (argtype) == COMPLEX_TYPE
1665 && targetm.calls.split_complex_arg (argtype))
1667 tree subtype = TREE_TYPE (argtype);
1668 args[j].tree_value = build1 (REALPART_EXPR, subtype, arg);
1669 j--;
1670 args[j].tree_value = build1 (IMAGPART_EXPR, subtype, arg);
1672 else
1673 args[j].tree_value = arg;
1674 j--;
1675 argpos++;
1678 if (slots)
1679 BITMAP_FREE (slots);
1682 bitmap_obstack_release (NULL);
1684 /* Extract attribute alloc_size and if set, store the indices of
1685 the corresponding arguments in ALLOC_IDX, and then the actual
1686 argument(s) at those indices in ALLOC_ARGS. */
1687 int alloc_idx[2] = { -1, -1 };
1688 if (tree alloc_size
1689 = (fndecl ? lookup_attribute ("alloc_size",
1690 TYPE_ATTRIBUTES (TREE_TYPE (fndecl)))
1691 : NULL_TREE))
1693 tree args = TREE_VALUE (alloc_size);
1694 alloc_idx[0] = TREE_INT_CST_LOW (TREE_VALUE (args)) - 1;
1695 if (TREE_CHAIN (args))
1696 alloc_idx[1] = TREE_INT_CST_LOW (TREE_VALUE (TREE_CHAIN (args))) - 1;
1699 /* Array for up to the two attribute alloc_size arguments. */
1700 tree alloc_args[] = { NULL_TREE, NULL_TREE };
1702 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1703 for (argpos = 0; argpos < num_actuals; i--, argpos++)
1705 tree type = TREE_TYPE (args[i].tree_value);
1706 int unsignedp;
1707 machine_mode mode;
1709 /* Replace erroneous argument with constant zero. */
1710 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1711 args[i].tree_value = integer_zero_node, type = integer_type_node;
1713 /* If TYPE is a transparent union or record, pass things the way
1714 we would pass the first field of the union or record. We have
1715 already verified that the modes are the same. */
1716 if ((TREE_CODE (type) == UNION_TYPE || TREE_CODE (type) == RECORD_TYPE)
1717 && TYPE_TRANSPARENT_AGGR (type))
1718 type = TREE_TYPE (first_field (type));
1720 /* Decide where to pass this arg.
1722 args[i].reg is nonzero if all or part is passed in registers.
1724 args[i].partial is nonzero if part but not all is passed in registers,
1725 and the exact value says how many bytes are passed in registers.
1727 args[i].pass_on_stack is nonzero if the argument must at least be
1728 computed on the stack. It may then be loaded back into registers
1729 if args[i].reg is nonzero.
1731 These decisions are driven by the FUNCTION_... macros and must agree
1732 with those made by function.c. */
1734 /* See if this argument should be passed by invisible reference. */
1735 if (pass_by_reference (args_so_far_pnt, TYPE_MODE (type),
1736 type, argpos < n_named_args))
1738 bool callee_copies;
1739 tree base = NULL_TREE;
1741 callee_copies
1742 = reference_callee_copied (args_so_far_pnt, TYPE_MODE (type),
1743 type, argpos < n_named_args);
1745 /* If we're compiling a thunk, pass through invisible references
1746 instead of making a copy. */
1747 if (call_from_thunk_p
1748 || (callee_copies
1749 && !TREE_ADDRESSABLE (type)
1750 && (base = get_base_address (args[i].tree_value))
1751 && TREE_CODE (base) != SSA_NAME
1752 && (!DECL_P (base) || MEM_P (DECL_RTL (base)))))
1754 /* We may have turned the parameter value into an SSA name.
1755 Go back to the original parameter so we can take the
1756 address. */
1757 if (TREE_CODE (args[i].tree_value) == SSA_NAME)
1759 gcc_assert (SSA_NAME_IS_DEFAULT_DEF (args[i].tree_value));
1760 args[i].tree_value = SSA_NAME_VAR (args[i].tree_value);
1761 gcc_assert (TREE_CODE (args[i].tree_value) == PARM_DECL);
1763 /* Argument setup code may have copied the value to register. We
1764 revert that optimization now because the tail call code must
1765 use the original location. */
1766 if (TREE_CODE (args[i].tree_value) == PARM_DECL
1767 && !MEM_P (DECL_RTL (args[i].tree_value))
1768 && DECL_INCOMING_RTL (args[i].tree_value)
1769 && MEM_P (DECL_INCOMING_RTL (args[i].tree_value)))
1770 set_decl_rtl (args[i].tree_value,
1771 DECL_INCOMING_RTL (args[i].tree_value));
1773 mark_addressable (args[i].tree_value);
1775 /* We can't use sibcalls if a callee-copied argument is
1776 stored in the current function's frame. */
1777 if (!call_from_thunk_p && DECL_P (base) && !TREE_STATIC (base))
1779 *may_tailcall = false;
1780 maybe_complain_about_tail_call (exp,
1781 "a callee-copied argument is"
1782 " stored in the current "
1783 " function's frame");
1786 args[i].tree_value = build_fold_addr_expr_loc (loc,
1787 args[i].tree_value);
1788 type = TREE_TYPE (args[i].tree_value);
1790 if (*ecf_flags & ECF_CONST)
1791 *ecf_flags &= ~(ECF_CONST | ECF_LOOPING_CONST_OR_PURE);
1793 else
1795 /* We make a copy of the object and pass the address to the
1796 function being called. */
1797 rtx copy;
1799 if (!COMPLETE_TYPE_P (type)
1800 || TREE_CODE (TYPE_SIZE_UNIT (type)) != INTEGER_CST
1801 || (flag_stack_check == GENERIC_STACK_CHECK
1802 && compare_tree_int (TYPE_SIZE_UNIT (type),
1803 STACK_CHECK_MAX_VAR_SIZE) > 0))
1805 /* This is a variable-sized object. Make space on the stack
1806 for it. */
1807 rtx size_rtx = expr_size (args[i].tree_value);
1809 if (*old_stack_level == 0)
1811 emit_stack_save (SAVE_BLOCK, old_stack_level);
1812 *old_pending_adj = pending_stack_adjust;
1813 pending_stack_adjust = 0;
1816 /* We can pass TRUE as the 4th argument because we just
1817 saved the stack pointer and will restore it right after
1818 the call. */
1819 copy = allocate_dynamic_stack_space (size_rtx,
1820 TYPE_ALIGN (type),
1821 TYPE_ALIGN (type),
1822 true);
1823 copy = gen_rtx_MEM (BLKmode, copy);
1824 set_mem_attributes (copy, type, 1);
1826 else
1827 copy = assign_temp (type, 1, 0);
1829 store_expr (args[i].tree_value, copy, 0, false, false);
1831 /* Just change the const function to pure and then let
1832 the next test clear the pure based on
1833 callee_copies. */
1834 if (*ecf_flags & ECF_CONST)
1836 *ecf_flags &= ~ECF_CONST;
1837 *ecf_flags |= ECF_PURE;
1840 if (!callee_copies && *ecf_flags & ECF_PURE)
1841 *ecf_flags &= ~(ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
1843 args[i].tree_value
1844 = build_fold_addr_expr_loc (loc, make_tree (type, copy));
1845 type = TREE_TYPE (args[i].tree_value);
1846 *may_tailcall = false;
1847 maybe_complain_about_tail_call (exp,
1848 "argument must be passed"
1849 " by copying");
1853 unsignedp = TYPE_UNSIGNED (type);
1854 mode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
1855 fndecl ? TREE_TYPE (fndecl) : fntype, 0);
1857 args[i].unsignedp = unsignedp;
1858 args[i].mode = mode;
1860 args[i].reg = targetm.calls.function_arg (args_so_far, mode, type,
1861 argpos < n_named_args);
1863 if (args[i].reg && CONST_INT_P (args[i].reg))
1865 args[i].special_slot = args[i].reg;
1866 args[i].reg = NULL;
1869 /* If this is a sibling call and the machine has register windows, the
1870 register window has to be unwinded before calling the routine, so
1871 arguments have to go into the incoming registers. */
1872 if (targetm.calls.function_incoming_arg != targetm.calls.function_arg)
1873 args[i].tail_call_reg
1874 = targetm.calls.function_incoming_arg (args_so_far, mode, type,
1875 argpos < n_named_args);
1876 else
1877 args[i].tail_call_reg = args[i].reg;
1879 if (args[i].reg)
1880 args[i].partial
1881 = targetm.calls.arg_partial_bytes (args_so_far, mode, type,
1882 argpos < n_named_args);
1884 args[i].pass_on_stack = targetm.calls.must_pass_in_stack (mode, type);
1886 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1887 it means that we are to pass this arg in the register(s) designated
1888 by the PARALLEL, but also to pass it in the stack. */
1889 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1890 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1891 args[i].pass_on_stack = 1;
1893 /* If this is an addressable type, we must preallocate the stack
1894 since we must evaluate the object into its final location.
1896 If this is to be passed in both registers and the stack, it is simpler
1897 to preallocate. */
1898 if (TREE_ADDRESSABLE (type)
1899 || (args[i].pass_on_stack && args[i].reg != 0))
1900 *must_preallocate = 1;
1902 /* No stack allocation and padding for bounds. */
1903 if (POINTER_BOUNDS_P (args[i].tree_value))
1905 /* Compute the stack-size of this argument. */
1906 else if (args[i].reg == 0 || args[i].partial != 0
1907 || reg_parm_stack_space > 0
1908 || args[i].pass_on_stack)
1909 locate_and_pad_parm (mode, type,
1910 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1912 #else
1913 args[i].reg != 0,
1914 #endif
1915 reg_parm_stack_space,
1916 args[i].pass_on_stack ? 0 : args[i].partial,
1917 fndecl, args_size, &args[i].locate);
1918 #ifdef BLOCK_REG_PADDING
1919 else
1920 /* The argument is passed entirely in registers. See at which
1921 end it should be padded. */
1922 args[i].locate.where_pad =
1923 BLOCK_REG_PADDING (mode, type,
1924 int_size_in_bytes (type) <= UNITS_PER_WORD);
1925 #endif
1927 /* Update ARGS_SIZE, the total stack space for args so far. */
1929 args_size->constant += args[i].locate.size.constant;
1930 if (args[i].locate.size.var)
1931 ADD_PARM_SIZE (*args_size, args[i].locate.size.var);
1933 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1934 have been used, etc. */
1936 targetm.calls.function_arg_advance (args_so_far, TYPE_MODE (type),
1937 type, argpos < n_named_args);
1939 /* Store argument values for functions decorated with attribute
1940 alloc_size. */
1941 if (argpos == alloc_idx[0])
1942 alloc_args[0] = args[i].tree_value;
1943 else if (argpos == alloc_idx[1])
1944 alloc_args[1] = args[i].tree_value;
1947 if (alloc_args[0])
1949 /* Check the arguments of functions decorated with attribute
1950 alloc_size. */
1951 maybe_warn_alloc_args_overflow (fndecl, exp, alloc_args, alloc_idx);
1955 /* Update ARGS_SIZE to contain the total size for the argument block.
1956 Return the original constant component of the argument block's size.
1958 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1959 for arguments passed in registers. */
1961 static int
1962 compute_argument_block_size (int reg_parm_stack_space,
1963 struct args_size *args_size,
1964 tree fndecl ATTRIBUTE_UNUSED,
1965 tree fntype ATTRIBUTE_UNUSED,
1966 int preferred_stack_boundary ATTRIBUTE_UNUSED)
1968 int unadjusted_args_size = args_size->constant;
1970 /* For accumulate outgoing args mode we don't need to align, since the frame
1971 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1972 backends from generating misaligned frame sizes. */
1973 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1974 preferred_stack_boundary = STACK_BOUNDARY;
1976 /* Compute the actual size of the argument block required. The variable
1977 and constant sizes must be combined, the size may have to be rounded,
1978 and there may be a minimum required size. */
1980 if (args_size->var)
1982 args_size->var = ARGS_SIZE_TREE (*args_size);
1983 args_size->constant = 0;
1985 preferred_stack_boundary /= BITS_PER_UNIT;
1986 if (preferred_stack_boundary > 1)
1988 /* We don't handle this case yet. To handle it correctly we have
1989 to add the delta, round and subtract the delta.
1990 Currently no machine description requires this support. */
1991 gcc_assert (!(stack_pointer_delta & (preferred_stack_boundary - 1)));
1992 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1995 if (reg_parm_stack_space > 0)
1997 args_size->var
1998 = size_binop (MAX_EXPR, args_size->var,
1999 ssize_int (reg_parm_stack_space));
2001 /* The area corresponding to register parameters is not to count in
2002 the size of the block we need. So make the adjustment. */
2003 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
2004 args_size->var
2005 = size_binop (MINUS_EXPR, args_size->var,
2006 ssize_int (reg_parm_stack_space));
2009 else
2011 preferred_stack_boundary /= BITS_PER_UNIT;
2012 if (preferred_stack_boundary < 1)
2013 preferred_stack_boundary = 1;
2014 args_size->constant = (((args_size->constant
2015 + stack_pointer_delta
2016 + preferred_stack_boundary - 1)
2017 / preferred_stack_boundary
2018 * preferred_stack_boundary)
2019 - stack_pointer_delta);
2021 args_size->constant = MAX (args_size->constant,
2022 reg_parm_stack_space);
2024 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
2025 args_size->constant -= reg_parm_stack_space;
2027 return unadjusted_args_size;
2030 /* Precompute parameters as needed for a function call.
2032 FLAGS is mask of ECF_* constants.
2034 NUM_ACTUALS is the number of arguments.
2036 ARGS is an array containing information for each argument; this
2037 routine fills in the INITIAL_VALUE and VALUE fields for each
2038 precomputed argument. */
2040 static void
2041 precompute_arguments (int num_actuals, struct arg_data *args)
2043 int i;
2045 /* If this is a libcall, then precompute all arguments so that we do not
2046 get extraneous instructions emitted as part of the libcall sequence. */
2048 /* If we preallocated the stack space, and some arguments must be passed
2049 on the stack, then we must precompute any parameter which contains a
2050 function call which will store arguments on the stack.
2051 Otherwise, evaluating the parameter may clobber previous parameters
2052 which have already been stored into the stack. (we have code to avoid
2053 such case by saving the outgoing stack arguments, but it results in
2054 worse code) */
2055 if (!ACCUMULATE_OUTGOING_ARGS)
2056 return;
2058 for (i = 0; i < num_actuals; i++)
2060 tree type;
2061 machine_mode mode;
2063 if (TREE_CODE (args[i].tree_value) != CALL_EXPR)
2064 continue;
2066 /* If this is an addressable type, we cannot pre-evaluate it. */
2067 type = TREE_TYPE (args[i].tree_value);
2068 gcc_assert (!TREE_ADDRESSABLE (type));
2070 args[i].initial_value = args[i].value
2071 = expand_normal (args[i].tree_value);
2073 mode = TYPE_MODE (type);
2074 if (mode != args[i].mode)
2076 int unsignedp = args[i].unsignedp;
2077 args[i].value
2078 = convert_modes (args[i].mode, mode,
2079 args[i].value, args[i].unsignedp);
2081 /* CSE will replace this only if it contains args[i].value
2082 pseudo, so convert it down to the declared mode using
2083 a SUBREG. */
2084 if (REG_P (args[i].value)
2085 && GET_MODE_CLASS (args[i].mode) == MODE_INT
2086 && promote_mode (type, mode, &unsignedp) != args[i].mode)
2088 args[i].initial_value
2089 = gen_lowpart_SUBREG (mode, args[i].value);
2090 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
2091 SUBREG_PROMOTED_SET (args[i].initial_value, args[i].unsignedp);
2097 /* Given the current state of MUST_PREALLOCATE and information about
2098 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
2099 compute and return the final value for MUST_PREALLOCATE. */
2101 static int
2102 finalize_must_preallocate (int must_preallocate, int num_actuals,
2103 struct arg_data *args, struct args_size *args_size)
2105 /* See if we have or want to preallocate stack space.
2107 If we would have to push a partially-in-regs parm
2108 before other stack parms, preallocate stack space instead.
2110 If the size of some parm is not a multiple of the required stack
2111 alignment, we must preallocate.
2113 If the total size of arguments that would otherwise create a copy in
2114 a temporary (such as a CALL) is more than half the total argument list
2115 size, preallocation is faster.
2117 Another reason to preallocate is if we have a machine (like the m88k)
2118 where stack alignment is required to be maintained between every
2119 pair of insns, not just when the call is made. However, we assume here
2120 that such machines either do not have push insns (and hence preallocation
2121 would occur anyway) or the problem is taken care of with
2122 PUSH_ROUNDING. */
2124 if (! must_preallocate)
2126 int partial_seen = 0;
2127 int copy_to_evaluate_size = 0;
2128 int i;
2130 for (i = 0; i < num_actuals && ! must_preallocate; i++)
2132 if (args[i].partial > 0 && ! args[i].pass_on_stack)
2133 partial_seen = 1;
2134 else if (partial_seen && args[i].reg == 0)
2135 must_preallocate = 1;
2136 /* We preallocate in case there are bounds passed
2137 in the bounds table to have precomputed address
2138 for bounds association. */
2139 else if (POINTER_BOUNDS_P (args[i].tree_value)
2140 && !args[i].reg)
2141 must_preallocate = 1;
2143 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
2144 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
2145 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
2146 || TREE_CODE (args[i].tree_value) == COND_EXPR
2147 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
2148 copy_to_evaluate_size
2149 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
2152 if (copy_to_evaluate_size * 2 >= args_size->constant
2153 && args_size->constant > 0)
2154 must_preallocate = 1;
2156 return must_preallocate;
2159 /* If we preallocated stack space, compute the address of each argument
2160 and store it into the ARGS array.
2162 We need not ensure it is a valid memory address here; it will be
2163 validized when it is used.
2165 ARGBLOCK is an rtx for the address of the outgoing arguments. */
2167 static void
2168 compute_argument_addresses (struct arg_data *args, rtx argblock, int num_actuals)
2170 if (argblock)
2172 rtx arg_reg = argblock;
2173 int i, arg_offset = 0;
2175 if (GET_CODE (argblock) == PLUS)
2176 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
2178 for (i = 0; i < num_actuals; i++)
2180 rtx offset = ARGS_SIZE_RTX (args[i].locate.offset);
2181 rtx slot_offset = ARGS_SIZE_RTX (args[i].locate.slot_offset);
2182 rtx addr;
2183 unsigned int align, boundary;
2184 unsigned int units_on_stack = 0;
2185 machine_mode partial_mode = VOIDmode;
2187 /* Skip this parm if it will not be passed on the stack. */
2188 if (! args[i].pass_on_stack
2189 && args[i].reg != 0
2190 && args[i].partial == 0)
2191 continue;
2193 /* Pointer Bounds are never passed on the stack. */
2194 if (POINTER_BOUNDS_P (args[i].tree_value))
2195 continue;
2197 addr = simplify_gen_binary (PLUS, Pmode, arg_reg, offset);
2198 addr = plus_constant (Pmode, addr, arg_offset);
2200 if (args[i].partial != 0)
2202 /* Only part of the parameter is being passed on the stack.
2203 Generate a simple memory reference of the correct size. */
2204 units_on_stack = args[i].locate.size.constant;
2205 unsigned int bits_on_stack = units_on_stack * BITS_PER_UNIT;
2206 partial_mode = int_mode_for_size (bits_on_stack, 1).else_blk ();
2207 args[i].stack = gen_rtx_MEM (partial_mode, addr);
2208 set_mem_size (args[i].stack, units_on_stack);
2210 else
2212 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
2213 set_mem_attributes (args[i].stack,
2214 TREE_TYPE (args[i].tree_value), 1);
2216 align = BITS_PER_UNIT;
2217 boundary = args[i].locate.boundary;
2218 if (args[i].locate.where_pad != PAD_DOWNWARD)
2219 align = boundary;
2220 else if (CONST_INT_P (offset))
2222 align = INTVAL (offset) * BITS_PER_UNIT | boundary;
2223 align = least_bit_hwi (align);
2225 set_mem_align (args[i].stack, align);
2227 addr = simplify_gen_binary (PLUS, Pmode, arg_reg, slot_offset);
2228 addr = plus_constant (Pmode, addr, arg_offset);
2230 if (args[i].partial != 0)
2232 /* Only part of the parameter is being passed on the stack.
2233 Generate a simple memory reference of the correct size.
2235 args[i].stack_slot = gen_rtx_MEM (partial_mode, addr);
2236 set_mem_size (args[i].stack_slot, units_on_stack);
2238 else
2240 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
2241 set_mem_attributes (args[i].stack_slot,
2242 TREE_TYPE (args[i].tree_value), 1);
2244 set_mem_align (args[i].stack_slot, args[i].locate.boundary);
2246 /* Function incoming arguments may overlap with sibling call
2247 outgoing arguments and we cannot allow reordering of reads
2248 from function arguments with stores to outgoing arguments
2249 of sibling calls. */
2250 set_mem_alias_set (args[i].stack, 0);
2251 set_mem_alias_set (args[i].stack_slot, 0);
2256 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
2257 in a call instruction.
2259 FNDECL is the tree node for the target function. For an indirect call
2260 FNDECL will be NULL_TREE.
2262 ADDR is the operand 0 of CALL_EXPR for this call. */
2264 static rtx
2265 rtx_for_function_call (tree fndecl, tree addr)
2267 rtx funexp;
2269 /* Get the function to call, in the form of RTL. */
2270 if (fndecl)
2272 if (!TREE_USED (fndecl) && fndecl != current_function_decl)
2273 TREE_USED (fndecl) = 1;
2275 /* Get a SYMBOL_REF rtx for the function address. */
2276 funexp = XEXP (DECL_RTL (fndecl), 0);
2278 else
2279 /* Generate an rtx (probably a pseudo-register) for the address. */
2281 push_temp_slots ();
2282 funexp = expand_normal (addr);
2283 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
2285 return funexp;
2288 /* Internal state for internal_arg_pointer_based_exp and its helpers. */
2289 static struct
2291 /* Last insn that has been scanned by internal_arg_pointer_based_exp_scan,
2292 or NULL_RTX if none has been scanned yet. */
2293 rtx_insn *scan_start;
2294 /* Vector indexed by REGNO - FIRST_PSEUDO_REGISTER, recording if a pseudo is
2295 based on crtl->args.internal_arg_pointer. The element is NULL_RTX if the
2296 pseudo isn't based on it, a CONST_INT offset if the pseudo is based on it
2297 with fixed offset, or PC if this is with variable or unknown offset. */
2298 vec<rtx> cache;
2299 } internal_arg_pointer_exp_state;
2301 static rtx internal_arg_pointer_based_exp (const_rtx, bool);
2303 /* Helper function for internal_arg_pointer_based_exp. Scan insns in
2304 the tail call sequence, starting with first insn that hasn't been
2305 scanned yet, and note for each pseudo on the LHS whether it is based
2306 on crtl->args.internal_arg_pointer or not, and what offset from that
2307 that pointer it has. */
2309 static void
2310 internal_arg_pointer_based_exp_scan (void)
2312 rtx_insn *insn, *scan_start = internal_arg_pointer_exp_state.scan_start;
2314 if (scan_start == NULL_RTX)
2315 insn = get_insns ();
2316 else
2317 insn = NEXT_INSN (scan_start);
2319 while (insn)
2321 rtx set = single_set (insn);
2322 if (set && REG_P (SET_DEST (set)) && !HARD_REGISTER_P (SET_DEST (set)))
2324 rtx val = NULL_RTX;
2325 unsigned int idx = REGNO (SET_DEST (set)) - FIRST_PSEUDO_REGISTER;
2326 /* Punt on pseudos set multiple times. */
2327 if (idx < internal_arg_pointer_exp_state.cache.length ()
2328 && (internal_arg_pointer_exp_state.cache[idx]
2329 != NULL_RTX))
2330 val = pc_rtx;
2331 else
2332 val = internal_arg_pointer_based_exp (SET_SRC (set), false);
2333 if (val != NULL_RTX)
2335 if (idx >= internal_arg_pointer_exp_state.cache.length ())
2336 internal_arg_pointer_exp_state.cache
2337 .safe_grow_cleared (idx + 1);
2338 internal_arg_pointer_exp_state.cache[idx] = val;
2341 if (NEXT_INSN (insn) == NULL_RTX)
2342 scan_start = insn;
2343 insn = NEXT_INSN (insn);
2346 internal_arg_pointer_exp_state.scan_start = scan_start;
2349 /* Compute whether RTL is based on crtl->args.internal_arg_pointer. Return
2350 NULL_RTX if RTL isn't based on it, a CONST_INT offset if RTL is based on
2351 it with fixed offset, or PC if this is with variable or unknown offset.
2352 TOPLEVEL is true if the function is invoked at the topmost level. */
2354 static rtx
2355 internal_arg_pointer_based_exp (const_rtx rtl, bool toplevel)
2357 if (CONSTANT_P (rtl))
2358 return NULL_RTX;
2360 if (rtl == crtl->args.internal_arg_pointer)
2361 return const0_rtx;
2363 if (REG_P (rtl) && HARD_REGISTER_P (rtl))
2364 return NULL_RTX;
2366 if (GET_CODE (rtl) == PLUS && CONST_INT_P (XEXP (rtl, 1)))
2368 rtx val = internal_arg_pointer_based_exp (XEXP (rtl, 0), toplevel);
2369 if (val == NULL_RTX || val == pc_rtx)
2370 return val;
2371 return plus_constant (Pmode, val, INTVAL (XEXP (rtl, 1)));
2374 /* When called at the topmost level, scan pseudo assignments in between the
2375 last scanned instruction in the tail call sequence and the latest insn
2376 in that sequence. */
2377 if (toplevel)
2378 internal_arg_pointer_based_exp_scan ();
2380 if (REG_P (rtl))
2382 unsigned int idx = REGNO (rtl) - FIRST_PSEUDO_REGISTER;
2383 if (idx < internal_arg_pointer_exp_state.cache.length ())
2384 return internal_arg_pointer_exp_state.cache[idx];
2386 return NULL_RTX;
2389 subrtx_iterator::array_type array;
2390 FOR_EACH_SUBRTX (iter, array, rtl, NONCONST)
2392 const_rtx x = *iter;
2393 if (REG_P (x) && internal_arg_pointer_based_exp (x, false) != NULL_RTX)
2394 return pc_rtx;
2395 if (MEM_P (x))
2396 iter.skip_subrtxes ();
2399 return NULL_RTX;
2402 /* Return true if and only if SIZE storage units (usually bytes)
2403 starting from address ADDR overlap with already clobbered argument
2404 area. This function is used to determine if we should give up a
2405 sibcall. */
2407 static bool
2408 mem_overlaps_already_clobbered_arg_p (rtx addr, unsigned HOST_WIDE_INT size)
2410 HOST_WIDE_INT i;
2411 rtx val;
2413 if (bitmap_empty_p (stored_args_map))
2414 return false;
2415 val = internal_arg_pointer_based_exp (addr, true);
2416 if (val == NULL_RTX)
2417 return false;
2418 else if (val == pc_rtx)
2419 return true;
2420 else
2421 i = INTVAL (val);
2423 if (STACK_GROWS_DOWNWARD)
2424 i -= crtl->args.pretend_args_size;
2425 else
2426 i += crtl->args.pretend_args_size;
2429 if (ARGS_GROW_DOWNWARD)
2430 i = -i - size;
2432 if (size > 0)
2434 unsigned HOST_WIDE_INT k;
2436 for (k = 0; k < size; k++)
2437 if (i + k < SBITMAP_SIZE (stored_args_map)
2438 && bitmap_bit_p (stored_args_map, i + k))
2439 return true;
2442 return false;
2445 /* Do the register loads required for any wholly-register parms or any
2446 parms which are passed both on the stack and in a register. Their
2447 expressions were already evaluated.
2449 Mark all register-parms as living through the call, putting these USE
2450 insns in the CALL_INSN_FUNCTION_USAGE field.
2452 When IS_SIBCALL, perform the check_sibcall_argument_overlap
2453 checking, setting *SIBCALL_FAILURE if appropriate. */
2455 static void
2456 load_register_parameters (struct arg_data *args, int num_actuals,
2457 rtx *call_fusage, int flags, int is_sibcall,
2458 int *sibcall_failure)
2460 int i, j;
2462 for (i = 0; i < num_actuals; i++)
2464 rtx reg = ((flags & ECF_SIBCALL)
2465 ? args[i].tail_call_reg : args[i].reg);
2466 if (reg)
2468 int partial = args[i].partial;
2469 int nregs;
2470 int size = 0;
2471 rtx_insn *before_arg = get_last_insn ();
2472 /* Set non-negative if we must move a word at a time, even if
2473 just one word (e.g, partial == 4 && mode == DFmode). Set
2474 to -1 if we just use a normal move insn. This value can be
2475 zero if the argument is a zero size structure. */
2476 nregs = -1;
2477 if (GET_CODE (reg) == PARALLEL)
2479 else if (partial)
2481 gcc_assert (partial % UNITS_PER_WORD == 0);
2482 nregs = partial / UNITS_PER_WORD;
2484 else if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode)
2486 size = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
2487 nregs = (size + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
2489 else
2490 size = GET_MODE_SIZE (args[i].mode);
2492 /* Handle calls that pass values in multiple non-contiguous
2493 locations. The Irix 6 ABI has examples of this. */
2495 if (GET_CODE (reg) == PARALLEL)
2496 emit_group_move (reg, args[i].parallel_value);
2498 /* If simple case, just do move. If normal partial, store_one_arg
2499 has already loaded the register for us. In all other cases,
2500 load the register(s) from memory. */
2502 else if (nregs == -1)
2504 emit_move_insn (reg, args[i].value);
2505 #ifdef BLOCK_REG_PADDING
2506 /* Handle case where we have a value that needs shifting
2507 up to the msb. eg. a QImode value and we're padding
2508 upward on a BYTES_BIG_ENDIAN machine. */
2509 if (size < UNITS_PER_WORD
2510 && (args[i].locate.where_pad
2511 == (BYTES_BIG_ENDIAN ? PAD_UPWARD : PAD_DOWNWARD)))
2513 rtx x;
2514 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
2516 /* Assigning REG here rather than a temp makes CALL_FUSAGE
2517 report the whole reg as used. Strictly speaking, the
2518 call only uses SIZE bytes at the msb end, but it doesn't
2519 seem worth generating rtl to say that. */
2520 reg = gen_rtx_REG (word_mode, REGNO (reg));
2521 x = expand_shift (LSHIFT_EXPR, word_mode, reg, shift, reg, 1);
2522 if (x != reg)
2523 emit_move_insn (reg, x);
2525 #endif
2528 /* If we have pre-computed the values to put in the registers in
2529 the case of non-aligned structures, copy them in now. */
2531 else if (args[i].n_aligned_regs != 0)
2532 for (j = 0; j < args[i].n_aligned_regs; j++)
2533 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
2534 args[i].aligned_regs[j]);
2536 else if (partial == 0 || args[i].pass_on_stack)
2538 rtx mem = validize_mem (copy_rtx (args[i].value));
2540 /* Check for overlap with already clobbered argument area,
2541 providing that this has non-zero size. */
2542 if (is_sibcall
2543 && size != 0
2544 && (mem_overlaps_already_clobbered_arg_p
2545 (XEXP (args[i].value, 0), size)))
2546 *sibcall_failure = 1;
2548 if (size % UNITS_PER_WORD == 0
2549 || MEM_ALIGN (mem) % BITS_PER_WORD == 0)
2550 move_block_to_reg (REGNO (reg), mem, nregs, args[i].mode);
2551 else
2553 if (nregs > 1)
2554 move_block_to_reg (REGNO (reg), mem, nregs - 1,
2555 args[i].mode);
2556 rtx dest = gen_rtx_REG (word_mode, REGNO (reg) + nregs - 1);
2557 unsigned int bitoff = (nregs - 1) * BITS_PER_WORD;
2558 unsigned int bitsize = size * BITS_PER_UNIT - bitoff;
2559 rtx x = extract_bit_field (mem, bitsize, bitoff, 1, dest,
2560 word_mode, word_mode, false,
2561 NULL);
2562 if (BYTES_BIG_ENDIAN)
2563 x = expand_shift (LSHIFT_EXPR, word_mode, x,
2564 BITS_PER_WORD - bitsize, dest, 1);
2565 if (x != dest)
2566 emit_move_insn (dest, x);
2569 /* Handle a BLKmode that needs shifting. */
2570 if (nregs == 1 && size < UNITS_PER_WORD
2571 #ifdef BLOCK_REG_PADDING
2572 && args[i].locate.where_pad == PAD_DOWNWARD
2573 #else
2574 && BYTES_BIG_ENDIAN
2575 #endif
2578 rtx dest = gen_rtx_REG (word_mode, REGNO (reg));
2579 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
2580 enum tree_code dir = (BYTES_BIG_ENDIAN
2581 ? RSHIFT_EXPR : LSHIFT_EXPR);
2582 rtx x;
2584 x = expand_shift (dir, word_mode, dest, shift, dest, 1);
2585 if (x != dest)
2586 emit_move_insn (dest, x);
2590 /* When a parameter is a block, and perhaps in other cases, it is
2591 possible that it did a load from an argument slot that was
2592 already clobbered. */
2593 if (is_sibcall
2594 && check_sibcall_argument_overlap (before_arg, &args[i], 0))
2595 *sibcall_failure = 1;
2597 /* Handle calls that pass values in multiple non-contiguous
2598 locations. The Irix 6 ABI has examples of this. */
2599 if (GET_CODE (reg) == PARALLEL)
2600 use_group_regs (call_fusage, reg);
2601 else if (nregs == -1)
2602 use_reg_mode (call_fusage, reg,
2603 TYPE_MODE (TREE_TYPE (args[i].tree_value)));
2604 else if (nregs > 0)
2605 use_regs (call_fusage, REGNO (reg), nregs);
2610 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
2611 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
2612 bytes, then we would need to push some additional bytes to pad the
2613 arguments. So, we compute an adjust to the stack pointer for an
2614 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
2615 bytes. Then, when the arguments are pushed the stack will be perfectly
2616 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
2617 be popped after the call. Returns the adjustment. */
2619 static int
2620 combine_pending_stack_adjustment_and_call (int unadjusted_args_size,
2621 struct args_size *args_size,
2622 unsigned int preferred_unit_stack_boundary)
2624 /* The number of bytes to pop so that the stack will be
2625 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
2626 HOST_WIDE_INT adjustment;
2627 /* The alignment of the stack after the arguments are pushed, if we
2628 just pushed the arguments without adjust the stack here. */
2629 unsigned HOST_WIDE_INT unadjusted_alignment;
2631 unadjusted_alignment
2632 = ((stack_pointer_delta + unadjusted_args_size)
2633 % preferred_unit_stack_boundary);
2635 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
2636 as possible -- leaving just enough left to cancel out the
2637 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
2638 PENDING_STACK_ADJUST is non-negative, and congruent to
2639 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
2641 /* Begin by trying to pop all the bytes. */
2642 unadjusted_alignment
2643 = (unadjusted_alignment
2644 - (pending_stack_adjust % preferred_unit_stack_boundary));
2645 adjustment = pending_stack_adjust;
2646 /* Push enough additional bytes that the stack will be aligned
2647 after the arguments are pushed. */
2648 if (preferred_unit_stack_boundary > 1 && unadjusted_alignment)
2649 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
2651 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
2652 bytes after the call. The right number is the entire
2653 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
2654 by the arguments in the first place. */
2655 args_size->constant
2656 = pending_stack_adjust - adjustment + unadjusted_args_size;
2658 return adjustment;
2661 /* Scan X expression if it does not dereference any argument slots
2662 we already clobbered by tail call arguments (as noted in stored_args_map
2663 bitmap).
2664 Return nonzero if X expression dereferences such argument slots,
2665 zero otherwise. */
2667 static int
2668 check_sibcall_argument_overlap_1 (rtx x)
2670 RTX_CODE code;
2671 int i, j;
2672 const char *fmt;
2674 if (x == NULL_RTX)
2675 return 0;
2677 code = GET_CODE (x);
2679 /* We need not check the operands of the CALL expression itself. */
2680 if (code == CALL)
2681 return 0;
2683 if (code == MEM)
2684 return mem_overlaps_already_clobbered_arg_p (XEXP (x, 0),
2685 GET_MODE_SIZE (GET_MODE (x)));
2687 /* Scan all subexpressions. */
2688 fmt = GET_RTX_FORMAT (code);
2689 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
2691 if (*fmt == 'e')
2693 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
2694 return 1;
2696 else if (*fmt == 'E')
2698 for (j = 0; j < XVECLEN (x, i); j++)
2699 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
2700 return 1;
2703 return 0;
2706 /* Scan sequence after INSN if it does not dereference any argument slots
2707 we already clobbered by tail call arguments (as noted in stored_args_map
2708 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
2709 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
2710 should be 0). Return nonzero if sequence after INSN dereferences such argument
2711 slots, zero otherwise. */
2713 static int
2714 check_sibcall_argument_overlap (rtx_insn *insn, struct arg_data *arg,
2715 int mark_stored_args_map)
2717 int low, high;
2719 if (insn == NULL_RTX)
2720 insn = get_insns ();
2721 else
2722 insn = NEXT_INSN (insn);
2724 for (; insn; insn = NEXT_INSN (insn))
2725 if (INSN_P (insn)
2726 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
2727 break;
2729 if (mark_stored_args_map)
2731 if (ARGS_GROW_DOWNWARD)
2732 low = -arg->locate.slot_offset.constant - arg->locate.size.constant;
2733 else
2734 low = arg->locate.slot_offset.constant;
2736 for (high = low + arg->locate.size.constant; low < high; low++)
2737 bitmap_set_bit (stored_args_map, low);
2739 return insn != NULL_RTX;
2742 /* Given that a function returns a value of mode MODE at the most
2743 significant end of hard register VALUE, shift VALUE left or right
2744 as specified by LEFT_P. Return true if some action was needed. */
2746 bool
2747 shift_return_value (machine_mode mode, bool left_p, rtx value)
2749 HOST_WIDE_INT shift;
2751 gcc_assert (REG_P (value) && HARD_REGISTER_P (value));
2752 shift = GET_MODE_BITSIZE (GET_MODE (value)) - GET_MODE_BITSIZE (mode);
2753 if (shift == 0)
2754 return false;
2756 /* Use ashr rather than lshr for right shifts. This is for the benefit
2757 of the MIPS port, which requires SImode values to be sign-extended
2758 when stored in 64-bit registers. */
2759 if (!force_expand_binop (GET_MODE (value), left_p ? ashl_optab : ashr_optab,
2760 value, GEN_INT (shift), value, 1, OPTAB_WIDEN))
2761 gcc_unreachable ();
2762 return true;
2765 /* If X is a likely-spilled register value, copy it to a pseudo
2766 register and return that register. Return X otherwise. */
2768 static rtx
2769 avoid_likely_spilled_reg (rtx x)
2771 rtx new_rtx;
2773 if (REG_P (x)
2774 && HARD_REGISTER_P (x)
2775 && targetm.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (x))))
2777 /* Make sure that we generate a REG rather than a CONCAT.
2778 Moves into CONCATs can need nontrivial instructions,
2779 and the whole point of this function is to avoid
2780 using the hard register directly in such a situation. */
2781 generating_concat_p = 0;
2782 new_rtx = gen_reg_rtx (GET_MODE (x));
2783 generating_concat_p = 1;
2784 emit_move_insn (new_rtx, x);
2785 return new_rtx;
2787 return x;
2790 /* Helper function for expand_call.
2791 Return false is EXP is not implementable as a sibling call. */
2793 static bool
2794 can_implement_as_sibling_call_p (tree exp,
2795 rtx structure_value_addr,
2796 tree funtype,
2797 int reg_parm_stack_space ATTRIBUTE_UNUSED,
2798 tree fndecl,
2799 int flags,
2800 tree addr,
2801 const args_size &args_size)
2803 if (!targetm.have_sibcall_epilogue ())
2805 maybe_complain_about_tail_call
2806 (exp,
2807 "machine description does not have"
2808 " a sibcall_epilogue instruction pattern");
2809 return false;
2812 /* Doing sibling call optimization needs some work, since
2813 structure_value_addr can be allocated on the stack.
2814 It does not seem worth the effort since few optimizable
2815 sibling calls will return a structure. */
2816 if (structure_value_addr != NULL_RTX)
2818 maybe_complain_about_tail_call (exp, "callee returns a structure");
2819 return false;
2822 #ifdef REG_PARM_STACK_SPACE
2823 /* If outgoing reg parm stack space changes, we can not do sibcall. */
2824 if (OUTGOING_REG_PARM_STACK_SPACE (funtype)
2825 != OUTGOING_REG_PARM_STACK_SPACE (TREE_TYPE (current_function_decl))
2826 || (reg_parm_stack_space != REG_PARM_STACK_SPACE (current_function_decl)))
2828 maybe_complain_about_tail_call (exp,
2829 "inconsistent size of stack space"
2830 " allocated for arguments which are"
2831 " passed in registers");
2832 return false;
2834 #endif
2836 /* Check whether the target is able to optimize the call
2837 into a sibcall. */
2838 if (!targetm.function_ok_for_sibcall (fndecl, exp))
2840 maybe_complain_about_tail_call (exp,
2841 "target is not able to optimize the"
2842 " call into a sibling call");
2843 return false;
2846 /* Functions that do not return exactly once may not be sibcall
2847 optimized. */
2848 if (flags & ECF_RETURNS_TWICE)
2850 maybe_complain_about_tail_call (exp, "callee returns twice");
2851 return false;
2853 if (flags & ECF_NORETURN)
2855 maybe_complain_about_tail_call (exp, "callee does not return");
2856 return false;
2859 if (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr))))
2861 maybe_complain_about_tail_call (exp, "volatile function type");
2862 return false;
2865 /* If the called function is nested in the current one, it might access
2866 some of the caller's arguments, but could clobber them beforehand if
2867 the argument areas are shared. */
2868 if (fndecl && decl_function_context (fndecl) == current_function_decl)
2870 maybe_complain_about_tail_call (exp, "nested function");
2871 return false;
2874 /* If this function requires more stack slots than the current
2875 function, we cannot change it into a sibling call.
2876 crtl->args.pretend_args_size is not part of the
2877 stack allocated by our caller. */
2878 if (args_size.constant > (crtl->args.size - crtl->args.pretend_args_size))
2880 maybe_complain_about_tail_call (exp,
2881 "callee required more stack slots"
2882 " than the caller");
2883 return false;
2886 /* If the callee pops its own arguments, then it must pop exactly
2887 the same number of arguments as the current function. */
2888 if (targetm.calls.return_pops_args (fndecl, funtype, args_size.constant)
2889 != targetm.calls.return_pops_args (current_function_decl,
2890 TREE_TYPE (current_function_decl),
2891 crtl->args.size))
2893 maybe_complain_about_tail_call (exp,
2894 "inconsistent number of"
2895 " popped arguments");
2896 return false;
2899 if (!lang_hooks.decls.ok_for_sibcall (fndecl))
2901 maybe_complain_about_tail_call (exp, "frontend does not support"
2902 " sibling call");
2903 return false;
2906 /* All checks passed. */
2907 return true;
2910 /* Generate all the code for a CALL_EXPR exp
2911 and return an rtx for its value.
2912 Store the value in TARGET (specified as an rtx) if convenient.
2913 If the value is stored in TARGET then TARGET is returned.
2914 If IGNORE is nonzero, then we ignore the value of the function call. */
2917 expand_call (tree exp, rtx target, int ignore)
2919 /* Nonzero if we are currently expanding a call. */
2920 static int currently_expanding_call = 0;
2922 /* RTX for the function to be called. */
2923 rtx funexp;
2924 /* Sequence of insns to perform a normal "call". */
2925 rtx_insn *normal_call_insns = NULL;
2926 /* Sequence of insns to perform a tail "call". */
2927 rtx_insn *tail_call_insns = NULL;
2928 /* Data type of the function. */
2929 tree funtype;
2930 tree type_arg_types;
2931 tree rettype;
2932 /* Declaration of the function being called,
2933 or 0 if the function is computed (not known by name). */
2934 tree fndecl = 0;
2935 /* The type of the function being called. */
2936 tree fntype;
2937 bool try_tail_call = CALL_EXPR_TAILCALL (exp);
2938 bool must_tail_call = CALL_EXPR_MUST_TAIL_CALL (exp);
2939 int pass;
2941 /* Register in which non-BLKmode value will be returned,
2942 or 0 if no value or if value is BLKmode. */
2943 rtx valreg;
2944 /* Register(s) in which bounds are returned. */
2945 rtx valbnd = NULL;
2946 /* Address where we should return a BLKmode value;
2947 0 if value not BLKmode. */
2948 rtx structure_value_addr = 0;
2949 /* Nonzero if that address is being passed by treating it as
2950 an extra, implicit first parameter. Otherwise,
2951 it is passed by being copied directly into struct_value_rtx. */
2952 int structure_value_addr_parm = 0;
2953 /* Holds the value of implicit argument for the struct value. */
2954 tree structure_value_addr_value = NULL_TREE;
2955 /* Size of aggregate value wanted, or zero if none wanted
2956 or if we are using the non-reentrant PCC calling convention
2957 or expecting the value in registers. */
2958 HOST_WIDE_INT struct_value_size = 0;
2959 /* Nonzero if called function returns an aggregate in memory PCC style,
2960 by returning the address of where to find it. */
2961 int pcc_struct_value = 0;
2962 rtx struct_value = 0;
2964 /* Number of actual parameters in this call, including struct value addr. */
2965 int num_actuals;
2966 /* Number of named args. Args after this are anonymous ones
2967 and they must all go on the stack. */
2968 int n_named_args;
2969 /* Number of complex actual arguments that need to be split. */
2970 int num_complex_actuals = 0;
2972 /* Vector of information about each argument.
2973 Arguments are numbered in the order they will be pushed,
2974 not the order they are written. */
2975 struct arg_data *args;
2977 /* Total size in bytes of all the stack-parms scanned so far. */
2978 struct args_size args_size;
2979 struct args_size adjusted_args_size;
2980 /* Size of arguments before any adjustments (such as rounding). */
2981 int unadjusted_args_size;
2982 /* Data on reg parms scanned so far. */
2983 CUMULATIVE_ARGS args_so_far_v;
2984 cumulative_args_t args_so_far;
2985 /* Nonzero if a reg parm has been scanned. */
2986 int reg_parm_seen;
2987 /* Nonzero if this is an indirect function call. */
2989 /* Nonzero if we must avoid push-insns in the args for this call.
2990 If stack space is allocated for register parameters, but not by the
2991 caller, then it is preallocated in the fixed part of the stack frame.
2992 So the entire argument block must then be preallocated (i.e., we
2993 ignore PUSH_ROUNDING in that case). */
2995 int must_preallocate = !PUSH_ARGS;
2997 /* Size of the stack reserved for parameter registers. */
2998 int reg_parm_stack_space = 0;
3000 /* Address of space preallocated for stack parms
3001 (on machines that lack push insns), or 0 if space not preallocated. */
3002 rtx argblock = 0;
3004 /* Mask of ECF_ and ERF_ flags. */
3005 int flags = 0;
3006 int return_flags = 0;
3007 #ifdef REG_PARM_STACK_SPACE
3008 /* Define the boundary of the register parm stack space that needs to be
3009 saved, if any. */
3010 int low_to_save, high_to_save;
3011 rtx save_area = 0; /* Place that it is saved */
3012 #endif
3014 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3015 char *initial_stack_usage_map = stack_usage_map;
3016 char *stack_usage_map_buf = NULL;
3018 int old_stack_allocated;
3020 /* State variables to track stack modifications. */
3021 rtx old_stack_level = 0;
3022 int old_stack_arg_under_construction = 0;
3023 int old_pending_adj = 0;
3024 int old_inhibit_defer_pop = inhibit_defer_pop;
3026 /* Some stack pointer alterations we make are performed via
3027 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
3028 which we then also need to save/restore along the way. */
3029 int old_stack_pointer_delta = 0;
3031 rtx call_fusage;
3032 tree addr = CALL_EXPR_FN (exp);
3033 int i;
3034 /* The alignment of the stack, in bits. */
3035 unsigned HOST_WIDE_INT preferred_stack_boundary;
3036 /* The alignment of the stack, in bytes. */
3037 unsigned HOST_WIDE_INT preferred_unit_stack_boundary;
3038 /* The static chain value to use for this call. */
3039 rtx static_chain_value;
3040 /* See if this is "nothrow" function call. */
3041 if (TREE_NOTHROW (exp))
3042 flags |= ECF_NOTHROW;
3044 /* See if we can find a DECL-node for the actual function, and get the
3045 function attributes (flags) from the function decl or type node. */
3046 fndecl = get_callee_fndecl (exp);
3047 if (fndecl)
3049 fntype = TREE_TYPE (fndecl);
3050 flags |= flags_from_decl_or_type (fndecl);
3051 return_flags |= decl_return_flags (fndecl);
3053 else
3055 fntype = TREE_TYPE (TREE_TYPE (addr));
3056 flags |= flags_from_decl_or_type (fntype);
3057 if (CALL_EXPR_BY_DESCRIPTOR (exp))
3058 flags |= ECF_BY_DESCRIPTOR;
3060 rettype = TREE_TYPE (exp);
3062 struct_value = targetm.calls.struct_value_rtx (fntype, 0);
3064 /* Warn if this value is an aggregate type,
3065 regardless of which calling convention we are using for it. */
3066 if (AGGREGATE_TYPE_P (rettype))
3067 warning (OPT_Waggregate_return, "function call has aggregate value");
3069 /* If the result of a non looping pure or const function call is
3070 ignored (or void), and none of its arguments are volatile, we can
3071 avoid expanding the call and just evaluate the arguments for
3072 side-effects. */
3073 if ((flags & (ECF_CONST | ECF_PURE))
3074 && (!(flags & ECF_LOOPING_CONST_OR_PURE))
3075 && (ignore || target == const0_rtx
3076 || TYPE_MODE (rettype) == VOIDmode))
3078 bool volatilep = false;
3079 tree arg;
3080 call_expr_arg_iterator iter;
3082 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
3083 if (TREE_THIS_VOLATILE (arg))
3085 volatilep = true;
3086 break;
3089 if (! volatilep)
3091 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
3092 expand_expr (arg, const0_rtx, VOIDmode, EXPAND_NORMAL);
3093 return const0_rtx;
3097 #ifdef REG_PARM_STACK_SPACE
3098 reg_parm_stack_space = REG_PARM_STACK_SPACE (!fndecl ? fntype : fndecl);
3099 #endif
3101 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl)))
3102 && reg_parm_stack_space > 0 && PUSH_ARGS)
3103 must_preallocate = 1;
3105 /* Set up a place to return a structure. */
3107 /* Cater to broken compilers. */
3108 if (aggregate_value_p (exp, fntype))
3110 /* This call returns a big structure. */
3111 flags &= ~(ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
3113 #ifdef PCC_STATIC_STRUCT_RETURN
3115 pcc_struct_value = 1;
3117 #else /* not PCC_STATIC_STRUCT_RETURN */
3119 struct_value_size = int_size_in_bytes (rettype);
3121 /* Even if it is semantically safe to use the target as the return
3122 slot, it may be not sufficiently aligned for the return type. */
3123 if (CALL_EXPR_RETURN_SLOT_OPT (exp)
3124 && target
3125 && MEM_P (target)
3126 && !(MEM_ALIGN (target) < TYPE_ALIGN (rettype)
3127 && targetm.slow_unaligned_access (TYPE_MODE (rettype),
3128 MEM_ALIGN (target))))
3129 structure_value_addr = XEXP (target, 0);
3130 else
3132 /* For variable-sized objects, we must be called with a target
3133 specified. If we were to allocate space on the stack here,
3134 we would have no way of knowing when to free it. */
3135 rtx d = assign_temp (rettype, 1, 1);
3136 structure_value_addr = XEXP (d, 0);
3137 target = 0;
3140 #endif /* not PCC_STATIC_STRUCT_RETURN */
3143 /* Figure out the amount to which the stack should be aligned. */
3144 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3145 if (fndecl)
3147 struct cgraph_rtl_info *i = cgraph_node::rtl_info (fndecl);
3148 /* Without automatic stack alignment, we can't increase preferred
3149 stack boundary. With automatic stack alignment, it is
3150 unnecessary since unless we can guarantee that all callers will
3151 align the outgoing stack properly, callee has to align its
3152 stack anyway. */
3153 if (i
3154 && i->preferred_incoming_stack_boundary
3155 && i->preferred_incoming_stack_boundary < preferred_stack_boundary)
3156 preferred_stack_boundary = i->preferred_incoming_stack_boundary;
3159 /* Operand 0 is a pointer-to-function; get the type of the function. */
3160 funtype = TREE_TYPE (addr);
3161 gcc_assert (POINTER_TYPE_P (funtype));
3162 funtype = TREE_TYPE (funtype);
3164 /* Count whether there are actual complex arguments that need to be split
3165 into their real and imaginary parts. Munge the type_arg_types
3166 appropriately here as well. */
3167 if (targetm.calls.split_complex_arg)
3169 call_expr_arg_iterator iter;
3170 tree arg;
3171 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
3173 tree type = TREE_TYPE (arg);
3174 if (type && TREE_CODE (type) == COMPLEX_TYPE
3175 && targetm.calls.split_complex_arg (type))
3176 num_complex_actuals++;
3178 type_arg_types = split_complex_types (TYPE_ARG_TYPES (funtype));
3180 else
3181 type_arg_types = TYPE_ARG_TYPES (funtype);
3183 if (flags & ECF_MAY_BE_ALLOCA)
3184 cfun->calls_alloca = 1;
3186 /* If struct_value_rtx is 0, it means pass the address
3187 as if it were an extra parameter. Put the argument expression
3188 in structure_value_addr_value. */
3189 if (structure_value_addr && struct_value == 0)
3191 /* If structure_value_addr is a REG other than
3192 virtual_outgoing_args_rtx, we can use always use it. If it
3193 is not a REG, we must always copy it into a register.
3194 If it is virtual_outgoing_args_rtx, we must copy it to another
3195 register in some cases. */
3196 rtx temp = (!REG_P (structure_value_addr)
3197 || (ACCUMULATE_OUTGOING_ARGS
3198 && stack_arg_under_construction
3199 && structure_value_addr == virtual_outgoing_args_rtx)
3200 ? copy_addr_to_reg (convert_memory_address
3201 (Pmode, structure_value_addr))
3202 : structure_value_addr);
3204 structure_value_addr_value =
3205 make_tree (build_pointer_type (TREE_TYPE (funtype)), temp);
3206 structure_value_addr_parm = CALL_WITH_BOUNDS_P (exp) ? 2 : 1;
3209 /* Count the arguments and set NUM_ACTUALS. */
3210 num_actuals =
3211 call_expr_nargs (exp) + num_complex_actuals + structure_value_addr_parm;
3213 /* Compute number of named args.
3214 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
3216 if (type_arg_types != 0)
3217 n_named_args
3218 = (list_length (type_arg_types)
3219 /* Count the struct value address, if it is passed as a parm. */
3220 + structure_value_addr_parm);
3221 else
3222 /* If we know nothing, treat all args as named. */
3223 n_named_args = num_actuals;
3225 /* Start updating where the next arg would go.
3227 On some machines (such as the PA) indirect calls have a different
3228 calling convention than normal calls. The fourth argument in
3229 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
3230 or not. */
3231 INIT_CUMULATIVE_ARGS (args_so_far_v, funtype, NULL_RTX, fndecl, n_named_args);
3232 args_so_far = pack_cumulative_args (&args_so_far_v);
3234 /* Now possibly adjust the number of named args.
3235 Normally, don't include the last named arg if anonymous args follow.
3236 We do include the last named arg if
3237 targetm.calls.strict_argument_naming() returns nonzero.
3238 (If no anonymous args follow, the result of list_length is actually
3239 one too large. This is harmless.)
3241 If targetm.calls.pretend_outgoing_varargs_named() returns
3242 nonzero, and targetm.calls.strict_argument_naming() returns zero,
3243 this machine will be able to place unnamed args that were passed
3244 in registers into the stack. So treat all args as named. This
3245 allows the insns emitting for a specific argument list to be
3246 independent of the function declaration.
3248 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
3249 we do not have any reliable way to pass unnamed args in
3250 registers, so we must force them into memory. */
3252 if (type_arg_types != 0
3253 && targetm.calls.strict_argument_naming (args_so_far))
3255 else if (type_arg_types != 0
3256 && ! targetm.calls.pretend_outgoing_varargs_named (args_so_far))
3257 /* Don't include the last named arg. */
3258 --n_named_args;
3259 else
3260 /* Treat all args as named. */
3261 n_named_args = num_actuals;
3263 /* Make a vector to hold all the information about each arg. */
3264 args = XCNEWVEC (struct arg_data, num_actuals);
3266 /* Build up entries in the ARGS array, compute the size of the
3267 arguments into ARGS_SIZE, etc. */
3268 initialize_argument_information (num_actuals, args, &args_size,
3269 n_named_args, exp,
3270 structure_value_addr_value, fndecl, fntype,
3271 args_so_far, reg_parm_stack_space,
3272 &old_stack_level, &old_pending_adj,
3273 &must_preallocate, &flags,
3274 &try_tail_call, CALL_FROM_THUNK_P (exp));
3276 if (args_size.var)
3277 must_preallocate = 1;
3279 /* Now make final decision about preallocating stack space. */
3280 must_preallocate = finalize_must_preallocate (must_preallocate,
3281 num_actuals, args,
3282 &args_size);
3284 /* If the structure value address will reference the stack pointer, we
3285 must stabilize it. We don't need to do this if we know that we are
3286 not going to adjust the stack pointer in processing this call. */
3288 if (structure_value_addr
3289 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
3290 || reg_mentioned_p (virtual_outgoing_args_rtx,
3291 structure_value_addr))
3292 && (args_size.var
3293 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
3294 structure_value_addr = copy_to_reg (structure_value_addr);
3296 /* Tail calls can make things harder to debug, and we've traditionally
3297 pushed these optimizations into -O2. Don't try if we're already
3298 expanding a call, as that means we're an argument. Don't try if
3299 there's cleanups, as we know there's code to follow the call. */
3301 if (currently_expanding_call++ != 0
3302 || !flag_optimize_sibling_calls
3303 || args_size.var
3304 || dbg_cnt (tail_call) == false)
3305 try_tail_call = 0;
3307 /* If the user has marked the function as requiring tail-call
3308 optimization, attempt it. */
3309 if (must_tail_call)
3310 try_tail_call = 1;
3312 /* Rest of purposes for tail call optimizations to fail. */
3313 if (try_tail_call)
3314 try_tail_call = can_implement_as_sibling_call_p (exp,
3315 structure_value_addr,
3316 funtype,
3317 reg_parm_stack_space,
3318 fndecl,
3319 flags, addr, args_size);
3321 /* Check if caller and callee disagree in promotion of function
3322 return value. */
3323 if (try_tail_call)
3325 machine_mode caller_mode, caller_promoted_mode;
3326 machine_mode callee_mode, callee_promoted_mode;
3327 int caller_unsignedp, callee_unsignedp;
3328 tree caller_res = DECL_RESULT (current_function_decl);
3330 caller_unsignedp = TYPE_UNSIGNED (TREE_TYPE (caller_res));
3331 caller_mode = DECL_MODE (caller_res);
3332 callee_unsignedp = TYPE_UNSIGNED (TREE_TYPE (funtype));
3333 callee_mode = TYPE_MODE (TREE_TYPE (funtype));
3334 caller_promoted_mode
3335 = promote_function_mode (TREE_TYPE (caller_res), caller_mode,
3336 &caller_unsignedp,
3337 TREE_TYPE (current_function_decl), 1);
3338 callee_promoted_mode
3339 = promote_function_mode (TREE_TYPE (funtype), callee_mode,
3340 &callee_unsignedp,
3341 funtype, 1);
3342 if (caller_mode != VOIDmode
3343 && (caller_promoted_mode != callee_promoted_mode
3344 || ((caller_mode != caller_promoted_mode
3345 || callee_mode != callee_promoted_mode)
3346 && (caller_unsignedp != callee_unsignedp
3347 || partial_subreg_p (caller_mode, callee_mode)))))
3349 try_tail_call = 0;
3350 maybe_complain_about_tail_call (exp,
3351 "caller and callee disagree in"
3352 " promotion of function"
3353 " return value");
3357 /* Ensure current function's preferred stack boundary is at least
3358 what we need. Stack alignment may also increase preferred stack
3359 boundary. */
3360 if (crtl->preferred_stack_boundary < preferred_stack_boundary)
3361 crtl->preferred_stack_boundary = preferred_stack_boundary;
3362 else
3363 preferred_stack_boundary = crtl->preferred_stack_boundary;
3365 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
3367 /* We want to make two insn chains; one for a sibling call, the other
3368 for a normal call. We will select one of the two chains after
3369 initial RTL generation is complete. */
3370 for (pass = try_tail_call ? 0 : 1; pass < 2; pass++)
3372 int sibcall_failure = 0;
3373 /* We want to emit any pending stack adjustments before the tail
3374 recursion "call". That way we know any adjustment after the tail
3375 recursion call can be ignored if we indeed use the tail
3376 call expansion. */
3377 saved_pending_stack_adjust save;
3378 rtx_insn *insns, *before_call, *after_args;
3379 rtx next_arg_reg;
3381 if (pass == 0)
3383 /* State variables we need to save and restore between
3384 iterations. */
3385 save_pending_stack_adjust (&save);
3387 if (pass)
3388 flags &= ~ECF_SIBCALL;
3389 else
3390 flags |= ECF_SIBCALL;
3392 /* Other state variables that we must reinitialize each time
3393 through the loop (that are not initialized by the loop itself). */
3394 argblock = 0;
3395 call_fusage = 0;
3397 /* Start a new sequence for the normal call case.
3399 From this point on, if the sibling call fails, we want to set
3400 sibcall_failure instead of continuing the loop. */
3401 start_sequence ();
3403 /* Don't let pending stack adjusts add up to too much.
3404 Also, do all pending adjustments now if there is any chance
3405 this might be a call to alloca or if we are expanding a sibling
3406 call sequence.
3407 Also do the adjustments before a throwing call, otherwise
3408 exception handling can fail; PR 19225. */
3409 if (pending_stack_adjust >= 32
3410 || (pending_stack_adjust > 0
3411 && (flags & ECF_MAY_BE_ALLOCA))
3412 || (pending_stack_adjust > 0
3413 && flag_exceptions && !(flags & ECF_NOTHROW))
3414 || pass == 0)
3415 do_pending_stack_adjust ();
3417 /* Precompute any arguments as needed. */
3418 if (pass)
3419 precompute_arguments (num_actuals, args);
3421 /* Now we are about to start emitting insns that can be deleted
3422 if a libcall is deleted. */
3423 if (pass && (flags & ECF_MALLOC))
3424 start_sequence ();
3426 if (pass == 0
3427 && crtl->stack_protect_guard
3428 && targetm.stack_protect_runtime_enabled_p ())
3429 stack_protect_epilogue ();
3431 adjusted_args_size = args_size;
3432 /* Compute the actual size of the argument block required. The variable
3433 and constant sizes must be combined, the size may have to be rounded,
3434 and there may be a minimum required size. When generating a sibcall
3435 pattern, do not round up, since we'll be re-using whatever space our
3436 caller provided. */
3437 unadjusted_args_size
3438 = compute_argument_block_size (reg_parm_stack_space,
3439 &adjusted_args_size,
3440 fndecl, fntype,
3441 (pass == 0 ? 0
3442 : preferred_stack_boundary));
3444 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
3446 /* The argument block when performing a sibling call is the
3447 incoming argument block. */
3448 if (pass == 0)
3450 argblock = crtl->args.internal_arg_pointer;
3451 if (STACK_GROWS_DOWNWARD)
3452 argblock
3453 = plus_constant (Pmode, argblock, crtl->args.pretend_args_size);
3454 else
3455 argblock
3456 = plus_constant (Pmode, argblock, -crtl->args.pretend_args_size);
3458 stored_args_map = sbitmap_alloc (args_size.constant);
3459 bitmap_clear (stored_args_map);
3462 /* If we have no actual push instructions, or shouldn't use them,
3463 make space for all args right now. */
3464 else if (adjusted_args_size.var != 0)
3466 if (old_stack_level == 0)
3468 emit_stack_save (SAVE_BLOCK, &old_stack_level);
3469 old_stack_pointer_delta = stack_pointer_delta;
3470 old_pending_adj = pending_stack_adjust;
3471 pending_stack_adjust = 0;
3472 /* stack_arg_under_construction says whether a stack arg is
3473 being constructed at the old stack level. Pushing the stack
3474 gets a clean outgoing argument block. */
3475 old_stack_arg_under_construction = stack_arg_under_construction;
3476 stack_arg_under_construction = 0;
3478 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
3479 if (flag_stack_usage_info)
3480 current_function_has_unbounded_dynamic_stack_size = 1;
3482 else
3484 /* Note that we must go through the motions of allocating an argument
3485 block even if the size is zero because we may be storing args
3486 in the area reserved for register arguments, which may be part of
3487 the stack frame. */
3489 int needed = adjusted_args_size.constant;
3491 /* Store the maximum argument space used. It will be pushed by
3492 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
3493 checking). */
3495 if (needed > crtl->outgoing_args_size)
3496 crtl->outgoing_args_size = needed;
3498 if (must_preallocate)
3500 if (ACCUMULATE_OUTGOING_ARGS)
3502 /* Since the stack pointer will never be pushed, it is
3503 possible for the evaluation of a parm to clobber
3504 something we have already written to the stack.
3505 Since most function calls on RISC machines do not use
3506 the stack, this is uncommon, but must work correctly.
3508 Therefore, we save any area of the stack that was already
3509 written and that we are using. Here we set up to do this
3510 by making a new stack usage map from the old one. The
3511 actual save will be done by store_one_arg.
3513 Another approach might be to try to reorder the argument
3514 evaluations to avoid this conflicting stack usage. */
3516 /* Since we will be writing into the entire argument area,
3517 the map must be allocated for its entire size, not just
3518 the part that is the responsibility of the caller. */
3519 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
3520 needed += reg_parm_stack_space;
3522 if (ARGS_GROW_DOWNWARD)
3523 highest_outgoing_arg_in_use
3524 = MAX (initial_highest_arg_in_use, needed + 1);
3525 else
3526 highest_outgoing_arg_in_use
3527 = MAX (initial_highest_arg_in_use, needed);
3529 free (stack_usage_map_buf);
3530 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
3531 stack_usage_map = stack_usage_map_buf;
3533 if (initial_highest_arg_in_use)
3534 memcpy (stack_usage_map, initial_stack_usage_map,
3535 initial_highest_arg_in_use);
3537 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3538 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
3539 (highest_outgoing_arg_in_use
3540 - initial_highest_arg_in_use));
3541 needed = 0;
3543 /* The address of the outgoing argument list must not be
3544 copied to a register here, because argblock would be left
3545 pointing to the wrong place after the call to
3546 allocate_dynamic_stack_space below. */
3548 argblock = virtual_outgoing_args_rtx;
3550 else
3552 if (inhibit_defer_pop == 0)
3554 /* Try to reuse some or all of the pending_stack_adjust
3555 to get this space. */
3556 needed
3557 = (combine_pending_stack_adjustment_and_call
3558 (unadjusted_args_size,
3559 &adjusted_args_size,
3560 preferred_unit_stack_boundary));
3562 /* combine_pending_stack_adjustment_and_call computes
3563 an adjustment before the arguments are allocated.
3564 Account for them and see whether or not the stack
3565 needs to go up or down. */
3566 needed = unadjusted_args_size - needed;
3568 if (needed < 0)
3570 /* We're releasing stack space. */
3571 /* ??? We can avoid any adjustment at all if we're
3572 already aligned. FIXME. */
3573 pending_stack_adjust = -needed;
3574 do_pending_stack_adjust ();
3575 needed = 0;
3577 else
3578 /* We need to allocate space. We'll do that in
3579 push_block below. */
3580 pending_stack_adjust = 0;
3583 /* Special case this because overhead of `push_block' in
3584 this case is non-trivial. */
3585 if (needed == 0)
3586 argblock = virtual_outgoing_args_rtx;
3587 else
3589 argblock = push_block (GEN_INT (needed), 0, 0);
3590 if (ARGS_GROW_DOWNWARD)
3591 argblock = plus_constant (Pmode, argblock, needed);
3594 /* We only really need to call `copy_to_reg' in the case
3595 where push insns are going to be used to pass ARGBLOCK
3596 to a function call in ARGS. In that case, the stack
3597 pointer changes value from the allocation point to the
3598 call point, and hence the value of
3599 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
3600 as well always do it. */
3601 argblock = copy_to_reg (argblock);
3606 if (ACCUMULATE_OUTGOING_ARGS)
3608 /* The save/restore code in store_one_arg handles all
3609 cases except one: a constructor call (including a C
3610 function returning a BLKmode struct) to initialize
3611 an argument. */
3612 if (stack_arg_under_construction)
3614 rtx push_size
3615 = GEN_INT (adjusted_args_size.constant
3616 + (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype
3617 : TREE_TYPE (fndecl))) ? 0
3618 : reg_parm_stack_space));
3619 if (old_stack_level == 0)
3621 emit_stack_save (SAVE_BLOCK, &old_stack_level);
3622 old_stack_pointer_delta = stack_pointer_delta;
3623 old_pending_adj = pending_stack_adjust;
3624 pending_stack_adjust = 0;
3625 /* stack_arg_under_construction says whether a stack
3626 arg is being constructed at the old stack level.
3627 Pushing the stack gets a clean outgoing argument
3628 block. */
3629 old_stack_arg_under_construction
3630 = stack_arg_under_construction;
3631 stack_arg_under_construction = 0;
3632 /* Make a new map for the new argument list. */
3633 free (stack_usage_map_buf);
3634 stack_usage_map_buf = XCNEWVEC (char, highest_outgoing_arg_in_use);
3635 stack_usage_map = stack_usage_map_buf;
3636 highest_outgoing_arg_in_use = 0;
3638 /* We can pass TRUE as the 4th argument because we just
3639 saved the stack pointer and will restore it right after
3640 the call. */
3641 allocate_dynamic_stack_space (push_size, 0,
3642 BIGGEST_ALIGNMENT, true);
3645 /* If argument evaluation might modify the stack pointer,
3646 copy the address of the argument list to a register. */
3647 for (i = 0; i < num_actuals; i++)
3648 if (args[i].pass_on_stack)
3650 argblock = copy_addr_to_reg (argblock);
3651 break;
3655 compute_argument_addresses (args, argblock, num_actuals);
3657 /* Stack is properly aligned, pops can't safely be deferred during
3658 the evaluation of the arguments. */
3659 NO_DEFER_POP;
3661 /* Precompute all register parameters. It isn't safe to compute
3662 anything once we have started filling any specific hard regs.
3663 TLS symbols sometimes need a call to resolve. Precompute
3664 register parameters before any stack pointer manipulation
3665 to avoid unaligned stack in the called function. */
3666 precompute_register_parameters (num_actuals, args, &reg_parm_seen);
3668 OK_DEFER_POP;
3670 /* Perform stack alignment before the first push (the last arg). */
3671 if (argblock == 0
3672 && adjusted_args_size.constant > reg_parm_stack_space
3673 && adjusted_args_size.constant != unadjusted_args_size)
3675 /* When the stack adjustment is pending, we get better code
3676 by combining the adjustments. */
3677 if (pending_stack_adjust
3678 && ! inhibit_defer_pop)
3680 pending_stack_adjust
3681 = (combine_pending_stack_adjustment_and_call
3682 (unadjusted_args_size,
3683 &adjusted_args_size,
3684 preferred_unit_stack_boundary));
3685 do_pending_stack_adjust ();
3687 else if (argblock == 0)
3688 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
3689 - unadjusted_args_size));
3691 /* Now that the stack is properly aligned, pops can't safely
3692 be deferred during the evaluation of the arguments. */
3693 NO_DEFER_POP;
3695 /* Record the maximum pushed stack space size. We need to delay
3696 doing it this far to take into account the optimization done
3697 by combine_pending_stack_adjustment_and_call. */
3698 if (flag_stack_usage_info
3699 && !ACCUMULATE_OUTGOING_ARGS
3700 && pass
3701 && adjusted_args_size.var == 0)
3703 int pushed = adjusted_args_size.constant + pending_stack_adjust;
3704 if (pushed > current_function_pushed_stack_size)
3705 current_function_pushed_stack_size = pushed;
3708 funexp = rtx_for_function_call (fndecl, addr);
3710 if (CALL_EXPR_STATIC_CHAIN (exp))
3711 static_chain_value = expand_normal (CALL_EXPR_STATIC_CHAIN (exp));
3712 else
3713 static_chain_value = 0;
3715 #ifdef REG_PARM_STACK_SPACE
3716 /* Save the fixed argument area if it's part of the caller's frame and
3717 is clobbered by argument setup for this call. */
3718 if (ACCUMULATE_OUTGOING_ARGS && pass)
3719 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
3720 &low_to_save, &high_to_save);
3721 #endif
3723 /* Now store (and compute if necessary) all non-register parms.
3724 These come before register parms, since they can require block-moves,
3725 which could clobber the registers used for register parms.
3726 Parms which have partial registers are not stored here,
3727 but we do preallocate space here if they want that. */
3729 for (i = 0; i < num_actuals; i++)
3731 /* Delay bounds until all other args are stored. */
3732 if (POINTER_BOUNDS_P (args[i].tree_value))
3733 continue;
3734 else if (args[i].reg == 0 || args[i].pass_on_stack)
3736 rtx_insn *before_arg = get_last_insn ();
3738 /* We don't allow passing huge (> 2^30 B) arguments
3739 by value. It would cause an overflow later on. */
3740 if (adjusted_args_size.constant
3741 >= (1 << (HOST_BITS_PER_INT - 2)))
3743 sorry ("passing too large argument on stack");
3744 continue;
3747 if (store_one_arg (&args[i], argblock, flags,
3748 adjusted_args_size.var != 0,
3749 reg_parm_stack_space)
3750 || (pass == 0
3751 && check_sibcall_argument_overlap (before_arg,
3752 &args[i], 1)))
3753 sibcall_failure = 1;
3756 if (args[i].stack)
3757 call_fusage
3758 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args[i].tree_value)),
3759 gen_rtx_USE (VOIDmode, args[i].stack),
3760 call_fusage);
3763 /* If we have a parm that is passed in registers but not in memory
3764 and whose alignment does not permit a direct copy into registers,
3765 make a group of pseudos that correspond to each register that we
3766 will later fill. */
3767 if (STRICT_ALIGNMENT)
3768 store_unaligned_arguments_into_pseudos (args, num_actuals);
3770 /* Now store any partially-in-registers parm.
3771 This is the last place a block-move can happen. */
3772 if (reg_parm_seen)
3773 for (i = 0; i < num_actuals; i++)
3774 if (args[i].partial != 0 && ! args[i].pass_on_stack)
3776 rtx_insn *before_arg = get_last_insn ();
3778 /* On targets with weird calling conventions (e.g. PA) it's
3779 hard to ensure that all cases of argument overlap between
3780 stack and registers work. Play it safe and bail out. */
3781 if (ARGS_GROW_DOWNWARD && !STACK_GROWS_DOWNWARD)
3783 sibcall_failure = 1;
3784 break;
3787 if (store_one_arg (&args[i], argblock, flags,
3788 adjusted_args_size.var != 0,
3789 reg_parm_stack_space)
3790 || (pass == 0
3791 && check_sibcall_argument_overlap (before_arg,
3792 &args[i], 1)))
3793 sibcall_failure = 1;
3796 bool any_regs = false;
3797 for (i = 0; i < num_actuals; i++)
3798 if (args[i].reg != NULL_RTX)
3800 any_regs = true;
3801 targetm.calls.call_args (args[i].reg, funtype);
3803 if (!any_regs)
3804 targetm.calls.call_args (pc_rtx, funtype);
3806 /* Figure out the register where the value, if any, will come back. */
3807 valreg = 0;
3808 valbnd = 0;
3809 if (TYPE_MODE (rettype) != VOIDmode
3810 && ! structure_value_addr)
3812 if (pcc_struct_value)
3814 valreg = hard_function_value (build_pointer_type (rettype),
3815 fndecl, NULL, (pass == 0));
3816 if (CALL_WITH_BOUNDS_P (exp))
3817 valbnd = targetm.calls.
3818 chkp_function_value_bounds (build_pointer_type (rettype),
3819 fndecl, (pass == 0));
3821 else
3823 valreg = hard_function_value (rettype, fndecl, fntype,
3824 (pass == 0));
3825 if (CALL_WITH_BOUNDS_P (exp))
3826 valbnd = targetm.calls.chkp_function_value_bounds (rettype,
3827 fndecl,
3828 (pass == 0));
3831 /* If VALREG is a PARALLEL whose first member has a zero
3832 offset, use that. This is for targets such as m68k that
3833 return the same value in multiple places. */
3834 if (GET_CODE (valreg) == PARALLEL)
3836 rtx elem = XVECEXP (valreg, 0, 0);
3837 rtx where = XEXP (elem, 0);
3838 rtx offset = XEXP (elem, 1);
3839 if (offset == const0_rtx
3840 && GET_MODE (where) == GET_MODE (valreg))
3841 valreg = where;
3845 /* Store all bounds not passed in registers. */
3846 for (i = 0; i < num_actuals; i++)
3848 if (POINTER_BOUNDS_P (args[i].tree_value)
3849 && !args[i].reg)
3850 store_bounds (&args[i],
3851 args[i].pointer_arg == -1
3852 ? NULL
3853 : &args[args[i].pointer_arg]);
3856 /* If register arguments require space on the stack and stack space
3857 was not preallocated, allocate stack space here for arguments
3858 passed in registers. */
3859 if (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl)))
3860 && !ACCUMULATE_OUTGOING_ARGS
3861 && must_preallocate == 0 && reg_parm_stack_space > 0)
3862 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
3864 /* Pass the function the address in which to return a
3865 structure value. */
3866 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
3868 structure_value_addr
3869 = convert_memory_address (Pmode, structure_value_addr);
3870 emit_move_insn (struct_value,
3871 force_reg (Pmode,
3872 force_operand (structure_value_addr,
3873 NULL_RTX)));
3875 if (REG_P (struct_value))
3876 use_reg (&call_fusage, struct_value);
3879 after_args = get_last_insn ();
3880 funexp = prepare_call_address (fndecl ? fndecl : fntype, funexp,
3881 static_chain_value, &call_fusage,
3882 reg_parm_seen, flags);
3884 load_register_parameters (args, num_actuals, &call_fusage, flags,
3885 pass == 0, &sibcall_failure);
3887 /* Save a pointer to the last insn before the call, so that we can
3888 later safely search backwards to find the CALL_INSN. */
3889 before_call = get_last_insn ();
3891 /* Set up next argument register. For sibling calls on machines
3892 with register windows this should be the incoming register. */
3893 if (pass == 0)
3894 next_arg_reg = targetm.calls.function_incoming_arg (args_so_far,
3895 VOIDmode,
3896 void_type_node,
3897 true);
3898 else
3899 next_arg_reg = targetm.calls.function_arg (args_so_far,
3900 VOIDmode, void_type_node,
3901 true);
3903 if (pass == 1 && (return_flags & ERF_RETURNS_ARG))
3905 int arg_nr = return_flags & ERF_RETURN_ARG_MASK;
3906 arg_nr = num_actuals - arg_nr - 1;
3907 if (arg_nr >= 0
3908 && arg_nr < num_actuals
3909 && args[arg_nr].reg
3910 && valreg
3911 && REG_P (valreg)
3912 && GET_MODE (args[arg_nr].reg) == GET_MODE (valreg))
3913 call_fusage
3914 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args[arg_nr].tree_value)),
3915 gen_rtx_SET (valreg, args[arg_nr].reg),
3916 call_fusage);
3918 /* All arguments and registers used for the call must be set up by
3919 now! */
3921 /* Stack must be properly aligned now. */
3922 gcc_assert (!pass
3923 || !(stack_pointer_delta % preferred_unit_stack_boundary));
3925 /* Generate the actual call instruction. */
3926 emit_call_1 (funexp, exp, fndecl, funtype, unadjusted_args_size,
3927 adjusted_args_size.constant, struct_value_size,
3928 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
3929 flags, args_so_far);
3931 if (flag_ipa_ra)
3933 rtx_call_insn *last;
3934 rtx datum = NULL_RTX;
3935 if (fndecl != NULL_TREE)
3937 datum = XEXP (DECL_RTL (fndecl), 0);
3938 gcc_assert (datum != NULL_RTX
3939 && GET_CODE (datum) == SYMBOL_REF);
3941 last = last_call_insn ();
3942 add_reg_note (last, REG_CALL_DECL, datum);
3945 /* If the call setup or the call itself overlaps with anything
3946 of the argument setup we probably clobbered our call address.
3947 In that case we can't do sibcalls. */
3948 if (pass == 0
3949 && check_sibcall_argument_overlap (after_args, 0, 0))
3950 sibcall_failure = 1;
3952 /* If a non-BLKmode value is returned at the most significant end
3953 of a register, shift the register right by the appropriate amount
3954 and update VALREG accordingly. BLKmode values are handled by the
3955 group load/store machinery below. */
3956 if (!structure_value_addr
3957 && !pcc_struct_value
3958 && TYPE_MODE (rettype) != VOIDmode
3959 && TYPE_MODE (rettype) != BLKmode
3960 && REG_P (valreg)
3961 && targetm.calls.return_in_msb (rettype))
3963 if (shift_return_value (TYPE_MODE (rettype), false, valreg))
3964 sibcall_failure = 1;
3965 valreg = gen_rtx_REG (TYPE_MODE (rettype), REGNO (valreg));
3968 if (pass && (flags & ECF_MALLOC))
3970 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3971 rtx_insn *last, *insns;
3973 /* The return value from a malloc-like function is a pointer. */
3974 if (TREE_CODE (rettype) == POINTER_TYPE)
3975 mark_reg_pointer (temp, MALLOC_ABI_ALIGNMENT);
3977 emit_move_insn (temp, valreg);
3979 /* The return value from a malloc-like function can not alias
3980 anything else. */
3981 last = get_last_insn ();
3982 add_reg_note (last, REG_NOALIAS, temp);
3984 /* Write out the sequence. */
3985 insns = get_insns ();
3986 end_sequence ();
3987 emit_insn (insns);
3988 valreg = temp;
3991 /* For calls to `setjmp', etc., inform
3992 function.c:setjmp_warnings that it should complain if
3993 nonvolatile values are live. For functions that cannot
3994 return, inform flow that control does not fall through. */
3996 if ((flags & ECF_NORETURN) || pass == 0)
3998 /* The barrier must be emitted
3999 immediately after the CALL_INSN. Some ports emit more
4000 than just a CALL_INSN above, so we must search for it here. */
4002 rtx_insn *last = get_last_insn ();
4003 while (!CALL_P (last))
4005 last = PREV_INSN (last);
4006 /* There was no CALL_INSN? */
4007 gcc_assert (last != before_call);
4010 emit_barrier_after (last);
4012 /* Stack adjustments after a noreturn call are dead code.
4013 However when NO_DEFER_POP is in effect, we must preserve
4014 stack_pointer_delta. */
4015 if (inhibit_defer_pop == 0)
4017 stack_pointer_delta = old_stack_allocated;
4018 pending_stack_adjust = 0;
4022 /* If value type not void, return an rtx for the value. */
4024 if (TYPE_MODE (rettype) == VOIDmode
4025 || ignore)
4026 target = const0_rtx;
4027 else if (structure_value_addr)
4029 if (target == 0 || !MEM_P (target))
4031 target
4032 = gen_rtx_MEM (TYPE_MODE (rettype),
4033 memory_address (TYPE_MODE (rettype),
4034 structure_value_addr));
4035 set_mem_attributes (target, rettype, 1);
4038 else if (pcc_struct_value)
4040 /* This is the special C++ case where we need to
4041 know what the true target was. We take care to
4042 never use this value more than once in one expression. */
4043 target = gen_rtx_MEM (TYPE_MODE (rettype),
4044 copy_to_reg (valreg));
4045 set_mem_attributes (target, rettype, 1);
4047 /* Handle calls that return values in multiple non-contiguous locations.
4048 The Irix 6 ABI has examples of this. */
4049 else if (GET_CODE (valreg) == PARALLEL)
4051 if (target == 0)
4052 target = emit_group_move_into_temps (valreg);
4053 else if (rtx_equal_p (target, valreg))
4055 else if (GET_CODE (target) == PARALLEL)
4056 /* Handle the result of a emit_group_move_into_temps
4057 call in the previous pass. */
4058 emit_group_move (target, valreg);
4059 else
4060 emit_group_store (target, valreg, rettype,
4061 int_size_in_bytes (rettype));
4063 else if (target
4064 && GET_MODE (target) == TYPE_MODE (rettype)
4065 && GET_MODE (target) == GET_MODE (valreg))
4067 bool may_overlap = false;
4069 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
4070 reg to a plain register. */
4071 if (!REG_P (target) || HARD_REGISTER_P (target))
4072 valreg = avoid_likely_spilled_reg (valreg);
4074 /* If TARGET is a MEM in the argument area, and we have
4075 saved part of the argument area, then we can't store
4076 directly into TARGET as it may get overwritten when we
4077 restore the argument save area below. Don't work too
4078 hard though and simply force TARGET to a register if it
4079 is a MEM; the optimizer is quite likely to sort it out. */
4080 if (ACCUMULATE_OUTGOING_ARGS && pass && MEM_P (target))
4081 for (i = 0; i < num_actuals; i++)
4082 if (args[i].save_area)
4084 may_overlap = true;
4085 break;
4088 if (may_overlap)
4089 target = copy_to_reg (valreg);
4090 else
4092 /* TARGET and VALREG cannot be equal at this point
4093 because the latter would not have
4094 REG_FUNCTION_VALUE_P true, while the former would if
4095 it were referring to the same register.
4097 If they refer to the same register, this move will be
4098 a no-op, except when function inlining is being
4099 done. */
4100 emit_move_insn (target, valreg);
4102 /* If we are setting a MEM, this code must be executed.
4103 Since it is emitted after the call insn, sibcall
4104 optimization cannot be performed in that case. */
4105 if (MEM_P (target))
4106 sibcall_failure = 1;
4109 else
4110 target = copy_to_reg (avoid_likely_spilled_reg (valreg));
4112 /* If we promoted this return value, make the proper SUBREG.
4113 TARGET might be const0_rtx here, so be careful. */
4114 if (REG_P (target)
4115 && TYPE_MODE (rettype) != BLKmode
4116 && GET_MODE (target) != TYPE_MODE (rettype))
4118 tree type = rettype;
4119 int unsignedp = TYPE_UNSIGNED (type);
4120 int offset = 0;
4121 machine_mode pmode;
4123 /* Ensure we promote as expected, and get the new unsignedness. */
4124 pmode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
4125 funtype, 1);
4126 gcc_assert (GET_MODE (target) == pmode);
4128 if ((WORDS_BIG_ENDIAN || BYTES_BIG_ENDIAN)
4129 && (GET_MODE_SIZE (GET_MODE (target))
4130 > GET_MODE_SIZE (TYPE_MODE (type))))
4132 offset = GET_MODE_SIZE (GET_MODE (target))
4133 - GET_MODE_SIZE (TYPE_MODE (type));
4134 if (! BYTES_BIG_ENDIAN)
4135 offset = (offset / UNITS_PER_WORD) * UNITS_PER_WORD;
4136 else if (! WORDS_BIG_ENDIAN)
4137 offset %= UNITS_PER_WORD;
4140 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
4141 SUBREG_PROMOTED_VAR_P (target) = 1;
4142 SUBREG_PROMOTED_SET (target, unsignedp);
4145 /* If size of args is variable or this was a constructor call for a stack
4146 argument, restore saved stack-pointer value. */
4148 if (old_stack_level)
4150 rtx_insn *prev = get_last_insn ();
4152 emit_stack_restore (SAVE_BLOCK, old_stack_level);
4153 stack_pointer_delta = old_stack_pointer_delta;
4155 fixup_args_size_notes (prev, get_last_insn (), stack_pointer_delta);
4157 pending_stack_adjust = old_pending_adj;
4158 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
4159 stack_arg_under_construction = old_stack_arg_under_construction;
4160 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4161 stack_usage_map = initial_stack_usage_map;
4162 sibcall_failure = 1;
4164 else if (ACCUMULATE_OUTGOING_ARGS && pass)
4166 #ifdef REG_PARM_STACK_SPACE
4167 if (save_area)
4168 restore_fixed_argument_area (save_area, argblock,
4169 high_to_save, low_to_save);
4170 #endif
4172 /* If we saved any argument areas, restore them. */
4173 for (i = 0; i < num_actuals; i++)
4174 if (args[i].save_area)
4176 machine_mode save_mode = GET_MODE (args[i].save_area);
4177 rtx stack_area
4178 = gen_rtx_MEM (save_mode,
4179 memory_address (save_mode,
4180 XEXP (args[i].stack_slot, 0)));
4182 if (save_mode != BLKmode)
4183 emit_move_insn (stack_area, args[i].save_area);
4184 else
4185 emit_block_move (stack_area, args[i].save_area,
4186 GEN_INT (args[i].locate.size.constant),
4187 BLOCK_OP_CALL_PARM);
4190 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4191 stack_usage_map = initial_stack_usage_map;
4194 /* If this was alloca, record the new stack level. */
4195 if (flags & ECF_MAY_BE_ALLOCA)
4196 record_new_stack_level ();
4198 /* Free up storage we no longer need. */
4199 for (i = 0; i < num_actuals; ++i)
4200 free (args[i].aligned_regs);
4202 targetm.calls.end_call_args ();
4204 insns = get_insns ();
4205 end_sequence ();
4207 if (pass == 0)
4209 tail_call_insns = insns;
4211 /* Restore the pending stack adjustment now that we have
4212 finished generating the sibling call sequence. */
4214 restore_pending_stack_adjust (&save);
4216 /* Prepare arg structure for next iteration. */
4217 for (i = 0; i < num_actuals; i++)
4219 args[i].value = 0;
4220 args[i].aligned_regs = 0;
4221 args[i].stack = 0;
4224 sbitmap_free (stored_args_map);
4225 internal_arg_pointer_exp_state.scan_start = NULL;
4226 internal_arg_pointer_exp_state.cache.release ();
4228 else
4230 normal_call_insns = insns;
4232 /* Verify that we've deallocated all the stack we used. */
4233 gcc_assert ((flags & ECF_NORETURN)
4234 || (old_stack_allocated
4235 == stack_pointer_delta - pending_stack_adjust));
4238 /* If something prevents making this a sibling call,
4239 zero out the sequence. */
4240 if (sibcall_failure)
4241 tail_call_insns = NULL;
4242 else
4243 break;
4246 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
4247 arguments too, as argument area is now clobbered by the call. */
4248 if (tail_call_insns)
4250 emit_insn (tail_call_insns);
4251 crtl->tail_call_emit = true;
4253 else
4255 emit_insn (normal_call_insns);
4256 if (try_tail_call)
4257 /* Ideally we'd emit a message for all of the ways that it could
4258 have failed. */
4259 maybe_complain_about_tail_call (exp, "tail call production failed");
4262 currently_expanding_call--;
4264 free (stack_usage_map_buf);
4265 free (args);
4267 /* Join result with returned bounds so caller may use them if needed. */
4268 target = chkp_join_splitted_slot (target, valbnd);
4270 return target;
4273 /* A sibling call sequence invalidates any REG_EQUIV notes made for
4274 this function's incoming arguments.
4276 At the start of RTL generation we know the only REG_EQUIV notes
4277 in the rtl chain are those for incoming arguments, so we can look
4278 for REG_EQUIV notes between the start of the function and the
4279 NOTE_INSN_FUNCTION_BEG.
4281 This is (slight) overkill. We could keep track of the highest
4282 argument we clobber and be more selective in removing notes, but it
4283 does not seem to be worth the effort. */
4285 void
4286 fixup_tail_calls (void)
4288 rtx_insn *insn;
4290 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4292 rtx note;
4294 /* There are never REG_EQUIV notes for the incoming arguments
4295 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
4296 if (NOTE_P (insn)
4297 && NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG)
4298 break;
4300 note = find_reg_note (insn, REG_EQUIV, 0);
4301 if (note)
4302 remove_note (insn, note);
4303 note = find_reg_note (insn, REG_EQUIV, 0);
4304 gcc_assert (!note);
4308 /* Traverse a list of TYPES and expand all complex types into their
4309 components. */
4310 static tree
4311 split_complex_types (tree types)
4313 tree p;
4315 /* Before allocating memory, check for the common case of no complex. */
4316 for (p = types; p; p = TREE_CHAIN (p))
4318 tree type = TREE_VALUE (p);
4319 if (TREE_CODE (type) == COMPLEX_TYPE
4320 && targetm.calls.split_complex_arg (type))
4321 goto found;
4323 return types;
4325 found:
4326 types = copy_list (types);
4328 for (p = types; p; p = TREE_CHAIN (p))
4330 tree complex_type = TREE_VALUE (p);
4332 if (TREE_CODE (complex_type) == COMPLEX_TYPE
4333 && targetm.calls.split_complex_arg (complex_type))
4335 tree next, imag;
4337 /* Rewrite complex type with component type. */
4338 TREE_VALUE (p) = TREE_TYPE (complex_type);
4339 next = TREE_CHAIN (p);
4341 /* Add another component type for the imaginary part. */
4342 imag = build_tree_list (NULL_TREE, TREE_VALUE (p));
4343 TREE_CHAIN (p) = imag;
4344 TREE_CHAIN (imag) = next;
4346 /* Skip the newly created node. */
4347 p = TREE_CHAIN (p);
4351 return types;
4354 /* Output a library call to function ORGFUN (a SYMBOL_REF rtx)
4355 for a value of mode OUTMODE,
4356 with NARGS different arguments, passed as ARGS.
4357 Store the return value if RETVAL is nonzero: store it in VALUE if
4358 VALUE is nonnull, otherwise pick a convenient location. In either
4359 case return the location of the stored value.
4361 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for
4362 `const' calls, LCT_PURE for `pure' calls, or another LCT_ value for
4363 other types of library calls. */
4366 emit_library_call_value_1 (int retval, rtx orgfun, rtx value,
4367 enum libcall_type fn_type,
4368 machine_mode outmode, int nargs, rtx_mode_t *args)
4370 /* Total size in bytes of all the stack-parms scanned so far. */
4371 struct args_size args_size;
4372 /* Size of arguments before any adjustments (such as rounding). */
4373 struct args_size original_args_size;
4374 int argnum;
4375 rtx fun;
4376 /* Todo, choose the correct decl type of orgfun. Sadly this information
4377 isn't present here, so we default to native calling abi here. */
4378 tree fndecl ATTRIBUTE_UNUSED = NULL_TREE; /* library calls default to host calling abi ? */
4379 tree fntype ATTRIBUTE_UNUSED = NULL_TREE; /* library calls default to host calling abi ? */
4380 int count;
4381 rtx argblock = 0;
4382 CUMULATIVE_ARGS args_so_far_v;
4383 cumulative_args_t args_so_far;
4384 struct arg
4386 rtx value;
4387 machine_mode mode;
4388 rtx reg;
4389 int partial;
4390 struct locate_and_pad_arg_data locate;
4391 rtx save_area;
4393 struct arg *argvec;
4394 int old_inhibit_defer_pop = inhibit_defer_pop;
4395 rtx call_fusage = 0;
4396 rtx mem_value = 0;
4397 rtx valreg;
4398 int pcc_struct_value = 0;
4399 int struct_value_size = 0;
4400 int flags;
4401 int reg_parm_stack_space = 0;
4402 int needed;
4403 rtx_insn *before_call;
4404 bool have_push_fusage;
4405 tree tfom; /* type_for_mode (outmode, 0) */
4407 #ifdef REG_PARM_STACK_SPACE
4408 /* Define the boundary of the register parm stack space that needs to be
4409 save, if any. */
4410 int low_to_save = 0, high_to_save = 0;
4411 rtx save_area = 0; /* Place that it is saved. */
4412 #endif
4414 /* Size of the stack reserved for parameter registers. */
4415 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
4416 char *initial_stack_usage_map = stack_usage_map;
4417 char *stack_usage_map_buf = NULL;
4419 rtx struct_value = targetm.calls.struct_value_rtx (0, 0);
4421 #ifdef REG_PARM_STACK_SPACE
4422 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
4423 #endif
4425 /* By default, library functions cannot throw. */
4426 flags = ECF_NOTHROW;
4428 switch (fn_type)
4430 case LCT_NORMAL:
4431 break;
4432 case LCT_CONST:
4433 flags |= ECF_CONST;
4434 break;
4435 case LCT_PURE:
4436 flags |= ECF_PURE;
4437 break;
4438 case LCT_NORETURN:
4439 flags |= ECF_NORETURN;
4440 break;
4441 case LCT_THROW:
4442 flags &= ~ECF_NOTHROW;
4443 break;
4444 case LCT_RETURNS_TWICE:
4445 flags = ECF_RETURNS_TWICE;
4446 break;
4448 fun = orgfun;
4450 /* Ensure current function's preferred stack boundary is at least
4451 what we need. */
4452 if (crtl->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
4453 crtl->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
4455 /* If this kind of value comes back in memory,
4456 decide where in memory it should come back. */
4457 if (outmode != VOIDmode)
4459 tfom = lang_hooks.types.type_for_mode (outmode, 0);
4460 if (aggregate_value_p (tfom, 0))
4462 #ifdef PCC_STATIC_STRUCT_RETURN
4463 rtx pointer_reg
4464 = hard_function_value (build_pointer_type (tfom), 0, 0, 0);
4465 mem_value = gen_rtx_MEM (outmode, pointer_reg);
4466 pcc_struct_value = 1;
4467 if (value == 0)
4468 value = gen_reg_rtx (outmode);
4469 #else /* not PCC_STATIC_STRUCT_RETURN */
4470 struct_value_size = GET_MODE_SIZE (outmode);
4471 if (value != 0 && MEM_P (value))
4472 mem_value = value;
4473 else
4474 mem_value = assign_temp (tfom, 1, 1);
4475 #endif
4476 /* This call returns a big structure. */
4477 flags &= ~(ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
4480 else
4481 tfom = void_type_node;
4483 /* ??? Unfinished: must pass the memory address as an argument. */
4485 /* Copy all the libcall-arguments out of the varargs data
4486 and into a vector ARGVEC.
4488 Compute how to pass each argument. We only support a very small subset
4489 of the full argument passing conventions to limit complexity here since
4490 library functions shouldn't have many args. */
4492 argvec = XALLOCAVEC (struct arg, nargs + 1);
4493 memset (argvec, 0, (nargs + 1) * sizeof (struct arg));
4495 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
4496 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far_v, outmode, fun);
4497 #else
4498 INIT_CUMULATIVE_ARGS (args_so_far_v, NULL_TREE, fun, 0, nargs);
4499 #endif
4500 args_so_far = pack_cumulative_args (&args_so_far_v);
4502 args_size.constant = 0;
4503 args_size.var = 0;
4505 count = 0;
4507 push_temp_slots ();
4509 /* If there's a structure value address to be passed,
4510 either pass it in the special place, or pass it as an extra argument. */
4511 if (mem_value && struct_value == 0 && ! pcc_struct_value)
4513 rtx addr = XEXP (mem_value, 0);
4515 nargs++;
4517 /* Make sure it is a reasonable operand for a move or push insn. */
4518 if (!REG_P (addr) && !MEM_P (addr)
4519 && !(CONSTANT_P (addr)
4520 && targetm.legitimate_constant_p (Pmode, addr)))
4521 addr = force_operand (addr, NULL_RTX);
4523 argvec[count].value = addr;
4524 argvec[count].mode = Pmode;
4525 argvec[count].partial = 0;
4527 argvec[count].reg = targetm.calls.function_arg (args_so_far,
4528 Pmode, NULL_TREE, true);
4529 gcc_assert (targetm.calls.arg_partial_bytes (args_so_far, Pmode,
4530 NULL_TREE, 1) == 0);
4532 locate_and_pad_parm (Pmode, NULL_TREE,
4533 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4535 #else
4536 argvec[count].reg != 0,
4537 #endif
4538 reg_parm_stack_space, 0,
4539 NULL_TREE, &args_size, &argvec[count].locate);
4541 if (argvec[count].reg == 0 || argvec[count].partial != 0
4542 || reg_parm_stack_space > 0)
4543 args_size.constant += argvec[count].locate.size.constant;
4545 targetm.calls.function_arg_advance (args_so_far, Pmode, (tree) 0, true);
4547 count++;
4550 for (unsigned int i = 0; count < nargs; i++, count++)
4552 rtx val = args[i].first;
4553 machine_mode mode = args[i].second;
4554 int unsigned_p = 0;
4556 /* We cannot convert the arg value to the mode the library wants here;
4557 must do it earlier where we know the signedness of the arg. */
4558 gcc_assert (mode != BLKmode
4559 && (GET_MODE (val) == mode || GET_MODE (val) == VOIDmode));
4561 /* Make sure it is a reasonable operand for a move or push insn. */
4562 if (!REG_P (val) && !MEM_P (val)
4563 && !(CONSTANT_P (val) && targetm.legitimate_constant_p (mode, val)))
4564 val = force_operand (val, NULL_RTX);
4566 if (pass_by_reference (&args_so_far_v, mode, NULL_TREE, 1))
4568 rtx slot;
4569 int must_copy
4570 = !reference_callee_copied (&args_so_far_v, mode, NULL_TREE, 1);
4572 /* If this was a CONST function, it is now PURE since it now
4573 reads memory. */
4574 if (flags & ECF_CONST)
4576 flags &= ~ECF_CONST;
4577 flags |= ECF_PURE;
4580 if (MEM_P (val) && !must_copy)
4582 tree val_expr = MEM_EXPR (val);
4583 if (val_expr)
4584 mark_addressable (val_expr);
4585 slot = val;
4587 else
4589 slot = assign_temp (lang_hooks.types.type_for_mode (mode, 0),
4590 1, 1);
4591 emit_move_insn (slot, val);
4594 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
4595 gen_rtx_USE (VOIDmode, slot),
4596 call_fusage);
4597 if (must_copy)
4598 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
4599 gen_rtx_CLOBBER (VOIDmode,
4600 slot),
4601 call_fusage);
4603 mode = Pmode;
4604 val = force_operand (XEXP (slot, 0), NULL_RTX);
4607 mode = promote_function_mode (NULL_TREE, mode, &unsigned_p, NULL_TREE, 0);
4608 argvec[count].mode = mode;
4609 argvec[count].value = convert_modes (mode, GET_MODE (val), val, unsigned_p);
4610 argvec[count].reg = targetm.calls.function_arg (args_so_far, mode,
4611 NULL_TREE, true);
4613 argvec[count].partial
4614 = targetm.calls.arg_partial_bytes (args_so_far, mode, NULL_TREE, 1);
4616 if (argvec[count].reg == 0
4617 || argvec[count].partial != 0
4618 || reg_parm_stack_space > 0)
4620 locate_and_pad_parm (mode, NULL_TREE,
4621 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4623 #else
4624 argvec[count].reg != 0,
4625 #endif
4626 reg_parm_stack_space, argvec[count].partial,
4627 NULL_TREE, &args_size, &argvec[count].locate);
4628 args_size.constant += argvec[count].locate.size.constant;
4629 gcc_assert (!argvec[count].locate.size.var);
4631 #ifdef BLOCK_REG_PADDING
4632 else
4633 /* The argument is passed entirely in registers. See at which
4634 end it should be padded. */
4635 argvec[count].locate.where_pad =
4636 BLOCK_REG_PADDING (mode, NULL_TREE,
4637 GET_MODE_SIZE (mode) <= UNITS_PER_WORD);
4638 #endif
4640 targetm.calls.function_arg_advance (args_so_far, mode, (tree) 0, true);
4643 /* If this machine requires an external definition for library
4644 functions, write one out. */
4645 assemble_external_libcall (fun);
4647 original_args_size = args_size;
4648 args_size.constant = (((args_size.constant
4649 + stack_pointer_delta
4650 + STACK_BYTES - 1)
4651 / STACK_BYTES
4652 * STACK_BYTES)
4653 - stack_pointer_delta);
4655 args_size.constant = MAX (args_size.constant,
4656 reg_parm_stack_space);
4658 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
4659 args_size.constant -= reg_parm_stack_space;
4661 if (args_size.constant > crtl->outgoing_args_size)
4662 crtl->outgoing_args_size = args_size.constant;
4664 if (flag_stack_usage_info && !ACCUMULATE_OUTGOING_ARGS)
4666 int pushed = args_size.constant + pending_stack_adjust;
4667 if (pushed > current_function_pushed_stack_size)
4668 current_function_pushed_stack_size = pushed;
4671 if (ACCUMULATE_OUTGOING_ARGS)
4673 /* Since the stack pointer will never be pushed, it is possible for
4674 the evaluation of a parm to clobber something we have already
4675 written to the stack. Since most function calls on RISC machines
4676 do not use the stack, this is uncommon, but must work correctly.
4678 Therefore, we save any area of the stack that was already written
4679 and that we are using. Here we set up to do this by making a new
4680 stack usage map from the old one.
4682 Another approach might be to try to reorder the argument
4683 evaluations to avoid this conflicting stack usage. */
4685 needed = args_size.constant;
4687 /* Since we will be writing into the entire argument area, the
4688 map must be allocated for its entire size, not just the part that
4689 is the responsibility of the caller. */
4690 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
4691 needed += reg_parm_stack_space;
4693 if (ARGS_GROW_DOWNWARD)
4694 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
4695 needed + 1);
4696 else
4697 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use, needed);
4699 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
4700 stack_usage_map = stack_usage_map_buf;
4702 if (initial_highest_arg_in_use)
4703 memcpy (stack_usage_map, initial_stack_usage_map,
4704 initial_highest_arg_in_use);
4706 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
4707 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
4708 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
4709 needed = 0;
4711 /* We must be careful to use virtual regs before they're instantiated,
4712 and real regs afterwards. Loop optimization, for example, can create
4713 new libcalls after we've instantiated the virtual regs, and if we
4714 use virtuals anyway, they won't match the rtl patterns. */
4716 if (virtuals_instantiated)
4717 argblock = plus_constant (Pmode, stack_pointer_rtx,
4718 STACK_POINTER_OFFSET);
4719 else
4720 argblock = virtual_outgoing_args_rtx;
4722 else
4724 if (!PUSH_ARGS)
4725 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
4728 /* We push args individually in reverse order, perform stack alignment
4729 before the first push (the last arg). */
4730 if (argblock == 0)
4731 anti_adjust_stack (GEN_INT (args_size.constant
4732 - original_args_size.constant));
4734 argnum = nargs - 1;
4736 #ifdef REG_PARM_STACK_SPACE
4737 if (ACCUMULATE_OUTGOING_ARGS)
4739 /* The argument list is the property of the called routine and it
4740 may clobber it. If the fixed area has been used for previous
4741 parameters, we must save and restore it. */
4742 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
4743 &low_to_save, &high_to_save);
4745 #endif
4747 /* When expanding a normal call, args are stored in push order,
4748 which is the reverse of what we have here. */
4749 bool any_regs = false;
4750 for (int i = nargs; i-- > 0; )
4751 if (argvec[i].reg != NULL_RTX)
4753 targetm.calls.call_args (argvec[i].reg, NULL_TREE);
4754 any_regs = true;
4756 if (!any_regs)
4757 targetm.calls.call_args (pc_rtx, NULL_TREE);
4759 /* Push the args that need to be pushed. */
4761 have_push_fusage = false;
4763 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4764 are to be pushed. */
4765 for (count = 0; count < nargs; count++, argnum--)
4767 machine_mode mode = argvec[argnum].mode;
4768 rtx val = argvec[argnum].value;
4769 rtx reg = argvec[argnum].reg;
4770 int partial = argvec[argnum].partial;
4771 unsigned int parm_align = argvec[argnum].locate.boundary;
4772 int lower_bound = 0, upper_bound = 0, i;
4774 if (! (reg != 0 && partial == 0))
4776 rtx use;
4778 if (ACCUMULATE_OUTGOING_ARGS)
4780 /* If this is being stored into a pre-allocated, fixed-size,
4781 stack area, save any previous data at that location. */
4783 if (ARGS_GROW_DOWNWARD)
4785 /* stack_slot is negative, but we want to index stack_usage_map
4786 with positive values. */
4787 upper_bound = -argvec[argnum].locate.slot_offset.constant + 1;
4788 lower_bound = upper_bound - argvec[argnum].locate.size.constant;
4790 else
4792 lower_bound = argvec[argnum].locate.slot_offset.constant;
4793 upper_bound = lower_bound + argvec[argnum].locate.size.constant;
4796 i = lower_bound;
4797 /* Don't worry about things in the fixed argument area;
4798 it has already been saved. */
4799 if (i < reg_parm_stack_space)
4800 i = reg_parm_stack_space;
4801 while (i < upper_bound && stack_usage_map[i] == 0)
4802 i++;
4804 if (i < upper_bound)
4806 /* We need to make a save area. */
4807 unsigned int size
4808 = argvec[argnum].locate.size.constant * BITS_PER_UNIT;
4809 machine_mode save_mode
4810 = int_mode_for_size (size, 1).else_blk ();
4811 rtx adr
4812 = plus_constant (Pmode, argblock,
4813 argvec[argnum].locate.offset.constant);
4814 rtx stack_area
4815 = gen_rtx_MEM (save_mode, memory_address (save_mode, adr));
4817 if (save_mode == BLKmode)
4819 argvec[argnum].save_area
4820 = assign_stack_temp (BLKmode,
4821 argvec[argnum].locate.size.constant
4824 emit_block_move (validize_mem
4825 (copy_rtx (argvec[argnum].save_area)),
4826 stack_area,
4827 GEN_INT (argvec[argnum].locate.size.constant),
4828 BLOCK_OP_CALL_PARM);
4830 else
4832 argvec[argnum].save_area = gen_reg_rtx (save_mode);
4834 emit_move_insn (argvec[argnum].save_area, stack_area);
4839 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, parm_align,
4840 partial, reg, 0, argblock,
4841 GEN_INT (argvec[argnum].locate.offset.constant),
4842 reg_parm_stack_space,
4843 ARGS_SIZE_RTX (argvec[argnum].locate.alignment_pad), false);
4845 /* Now mark the segment we just used. */
4846 if (ACCUMULATE_OUTGOING_ARGS)
4847 for (i = lower_bound; i < upper_bound; i++)
4848 stack_usage_map[i] = 1;
4850 NO_DEFER_POP;
4852 /* Indicate argument access so that alias.c knows that these
4853 values are live. */
4854 if (argblock)
4855 use = plus_constant (Pmode, argblock,
4856 argvec[argnum].locate.offset.constant);
4857 else if (have_push_fusage)
4858 continue;
4859 else
4861 /* When arguments are pushed, trying to tell alias.c where
4862 exactly this argument is won't work, because the
4863 auto-increment causes confusion. So we merely indicate
4864 that we access something with a known mode somewhere on
4865 the stack. */
4866 use = gen_rtx_PLUS (Pmode, stack_pointer_rtx,
4867 gen_rtx_SCRATCH (Pmode));
4868 have_push_fusage = true;
4870 use = gen_rtx_MEM (argvec[argnum].mode, use);
4871 use = gen_rtx_USE (VOIDmode, use);
4872 call_fusage = gen_rtx_EXPR_LIST (VOIDmode, use, call_fusage);
4876 argnum = nargs - 1;
4878 fun = prepare_call_address (NULL, fun, NULL, &call_fusage, 0, 0);
4880 /* Now load any reg parms into their regs. */
4882 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4883 are to be pushed. */
4884 for (count = 0; count < nargs; count++, argnum--)
4886 machine_mode mode = argvec[argnum].mode;
4887 rtx val = argvec[argnum].value;
4888 rtx reg = argvec[argnum].reg;
4889 int partial = argvec[argnum].partial;
4890 #ifdef BLOCK_REG_PADDING
4891 int size = 0;
4892 #endif
4894 /* Handle calls that pass values in multiple non-contiguous
4895 locations. The PA64 has examples of this for library calls. */
4896 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4897 emit_group_load (reg, val, NULL_TREE, GET_MODE_SIZE (mode));
4898 else if (reg != 0 && partial == 0)
4900 emit_move_insn (reg, val);
4901 #ifdef BLOCK_REG_PADDING
4902 size = GET_MODE_SIZE (argvec[argnum].mode);
4904 /* Copied from load_register_parameters. */
4906 /* Handle case where we have a value that needs shifting
4907 up to the msb. eg. a QImode value and we're padding
4908 upward on a BYTES_BIG_ENDIAN machine. */
4909 if (size < UNITS_PER_WORD
4910 && (argvec[argnum].locate.where_pad
4911 == (BYTES_BIG_ENDIAN ? PAD_UPWARD : PAD_DOWNWARD)))
4913 rtx x;
4914 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
4916 /* Assigning REG here rather than a temp makes CALL_FUSAGE
4917 report the whole reg as used. Strictly speaking, the
4918 call only uses SIZE bytes at the msb end, but it doesn't
4919 seem worth generating rtl to say that. */
4920 reg = gen_rtx_REG (word_mode, REGNO (reg));
4921 x = expand_shift (LSHIFT_EXPR, word_mode, reg, shift, reg, 1);
4922 if (x != reg)
4923 emit_move_insn (reg, x);
4925 #endif
4928 NO_DEFER_POP;
4931 /* Any regs containing parms remain in use through the call. */
4932 for (count = 0; count < nargs; count++)
4934 rtx reg = argvec[count].reg;
4935 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4936 use_group_regs (&call_fusage, reg);
4937 else if (reg != 0)
4939 int partial = argvec[count].partial;
4940 if (partial)
4942 int nregs;
4943 gcc_assert (partial % UNITS_PER_WORD == 0);
4944 nregs = partial / UNITS_PER_WORD;
4945 use_regs (&call_fusage, REGNO (reg), nregs);
4947 else
4948 use_reg (&call_fusage, reg);
4952 /* Pass the function the address in which to return a structure value. */
4953 if (mem_value != 0 && struct_value != 0 && ! pcc_struct_value)
4955 emit_move_insn (struct_value,
4956 force_reg (Pmode,
4957 force_operand (XEXP (mem_value, 0),
4958 NULL_RTX)));
4959 if (REG_P (struct_value))
4960 use_reg (&call_fusage, struct_value);
4963 /* Don't allow popping to be deferred, since then
4964 cse'ing of library calls could delete a call and leave the pop. */
4965 NO_DEFER_POP;
4966 valreg = (mem_value == 0 && outmode != VOIDmode
4967 ? hard_libcall_value (outmode, orgfun) : NULL_RTX);
4969 /* Stack must be properly aligned now. */
4970 gcc_assert (!(stack_pointer_delta
4971 & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1)));
4973 before_call = get_last_insn ();
4975 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4976 will set inhibit_defer_pop to that value. */
4977 /* The return type is needed to decide how many bytes the function pops.
4978 Signedness plays no role in that, so for simplicity, we pretend it's
4979 always signed. We also assume that the list of arguments passed has
4980 no impact, so we pretend it is unknown. */
4982 emit_call_1 (fun, NULL,
4983 get_identifier (XSTR (orgfun, 0)),
4984 build_function_type (tfom, NULL_TREE),
4985 original_args_size.constant, args_size.constant,
4986 struct_value_size,
4987 targetm.calls.function_arg (args_so_far,
4988 VOIDmode, void_type_node, true),
4989 valreg,
4990 old_inhibit_defer_pop + 1, call_fusage, flags, args_so_far);
4992 if (flag_ipa_ra)
4994 rtx datum = orgfun;
4995 gcc_assert (GET_CODE (datum) == SYMBOL_REF);
4996 rtx_call_insn *last = last_call_insn ();
4997 add_reg_note (last, REG_CALL_DECL, datum);
5000 /* Right-shift returned value if necessary. */
5001 if (!pcc_struct_value
5002 && TYPE_MODE (tfom) != BLKmode
5003 && targetm.calls.return_in_msb (tfom))
5005 shift_return_value (TYPE_MODE (tfom), false, valreg);
5006 valreg = gen_rtx_REG (TYPE_MODE (tfom), REGNO (valreg));
5009 targetm.calls.end_call_args ();
5011 /* For calls to `setjmp', etc., inform function.c:setjmp_warnings
5012 that it should complain if nonvolatile values are live. For
5013 functions that cannot return, inform flow that control does not
5014 fall through. */
5015 if (flags & ECF_NORETURN)
5017 /* The barrier note must be emitted
5018 immediately after the CALL_INSN. Some ports emit more than
5019 just a CALL_INSN above, so we must search for it here. */
5020 rtx_insn *last = get_last_insn ();
5021 while (!CALL_P (last))
5023 last = PREV_INSN (last);
5024 /* There was no CALL_INSN? */
5025 gcc_assert (last != before_call);
5028 emit_barrier_after (last);
5031 /* Consider that "regular" libcalls, i.e. all of them except for LCT_THROW
5032 and LCT_RETURNS_TWICE, cannot perform non-local gotos. */
5033 if (flags & ECF_NOTHROW)
5035 rtx_insn *last = get_last_insn ();
5036 while (!CALL_P (last))
5038 last = PREV_INSN (last);
5039 /* There was no CALL_INSN? */
5040 gcc_assert (last != before_call);
5043 make_reg_eh_region_note_nothrow_nononlocal (last);
5046 /* Now restore inhibit_defer_pop to its actual original value. */
5047 OK_DEFER_POP;
5049 pop_temp_slots ();
5051 /* Copy the value to the right place. */
5052 if (outmode != VOIDmode && retval)
5054 if (mem_value)
5056 if (value == 0)
5057 value = mem_value;
5058 if (value != mem_value)
5059 emit_move_insn (value, mem_value);
5061 else if (GET_CODE (valreg) == PARALLEL)
5063 if (value == 0)
5064 value = gen_reg_rtx (outmode);
5065 emit_group_store (value, valreg, NULL_TREE, GET_MODE_SIZE (outmode));
5067 else
5069 /* Convert to the proper mode if a promotion has been active. */
5070 if (GET_MODE (valreg) != outmode)
5072 int unsignedp = TYPE_UNSIGNED (tfom);
5074 gcc_assert (promote_function_mode (tfom, outmode, &unsignedp,
5075 fndecl ? TREE_TYPE (fndecl) : fntype, 1)
5076 == GET_MODE (valreg));
5077 valreg = convert_modes (outmode, GET_MODE (valreg), valreg, 0);
5080 if (value != 0)
5081 emit_move_insn (value, valreg);
5082 else
5083 value = valreg;
5087 if (ACCUMULATE_OUTGOING_ARGS)
5089 #ifdef REG_PARM_STACK_SPACE
5090 if (save_area)
5091 restore_fixed_argument_area (save_area, argblock,
5092 high_to_save, low_to_save);
5093 #endif
5095 /* If we saved any argument areas, restore them. */
5096 for (count = 0; count < nargs; count++)
5097 if (argvec[count].save_area)
5099 machine_mode save_mode = GET_MODE (argvec[count].save_area);
5100 rtx adr = plus_constant (Pmode, argblock,
5101 argvec[count].locate.offset.constant);
5102 rtx stack_area = gen_rtx_MEM (save_mode,
5103 memory_address (save_mode, adr));
5105 if (save_mode == BLKmode)
5106 emit_block_move (stack_area,
5107 validize_mem
5108 (copy_rtx (argvec[count].save_area)),
5109 GEN_INT (argvec[count].locate.size.constant),
5110 BLOCK_OP_CALL_PARM);
5111 else
5112 emit_move_insn (stack_area, argvec[count].save_area);
5115 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
5116 stack_usage_map = initial_stack_usage_map;
5119 free (stack_usage_map_buf);
5121 return value;
5126 /* Store pointer bounds argument ARG into Bounds Table entry
5127 associated with PARM. */
5128 static void
5129 store_bounds (struct arg_data *arg, struct arg_data *parm)
5131 rtx slot = NULL, ptr = NULL, addr = NULL;
5133 /* We may pass bounds not associated with any pointer. */
5134 if (!parm)
5136 gcc_assert (arg->special_slot);
5137 slot = arg->special_slot;
5138 ptr = const0_rtx;
5140 /* Find pointer associated with bounds and where it is
5141 passed. */
5142 else
5144 if (!parm->reg)
5146 gcc_assert (!arg->special_slot);
5148 addr = adjust_address (parm->stack, Pmode, arg->pointer_offset);
5150 else if (REG_P (parm->reg))
5152 gcc_assert (arg->special_slot);
5153 slot = arg->special_slot;
5155 if (MEM_P (parm->value))
5156 addr = adjust_address (parm->value, Pmode, arg->pointer_offset);
5157 else if (REG_P (parm->value))
5158 ptr = gen_rtx_SUBREG (Pmode, parm->value, arg->pointer_offset);
5159 else
5161 gcc_assert (!arg->pointer_offset);
5162 ptr = parm->value;
5165 else
5167 gcc_assert (GET_CODE (parm->reg) == PARALLEL);
5169 gcc_assert (arg->special_slot);
5170 slot = arg->special_slot;
5172 if (parm->parallel_value)
5173 ptr = chkp_get_value_with_offs (parm->parallel_value,
5174 GEN_INT (arg->pointer_offset));
5175 else
5176 gcc_unreachable ();
5180 /* Expand bounds. */
5181 if (!arg->value)
5182 arg->value = expand_normal (arg->tree_value);
5184 targetm.calls.store_bounds_for_arg (ptr, addr, arg->value, slot);
5187 /* Store a single argument for a function call
5188 into the register or memory area where it must be passed.
5189 *ARG describes the argument value and where to pass it.
5191 ARGBLOCK is the address of the stack-block for all the arguments,
5192 or 0 on a machine where arguments are pushed individually.
5194 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
5195 so must be careful about how the stack is used.
5197 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
5198 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
5199 that we need not worry about saving and restoring the stack.
5201 FNDECL is the declaration of the function we are calling.
5203 Return nonzero if this arg should cause sibcall failure,
5204 zero otherwise. */
5206 static int
5207 store_one_arg (struct arg_data *arg, rtx argblock, int flags,
5208 int variable_size ATTRIBUTE_UNUSED, int reg_parm_stack_space)
5210 tree pval = arg->tree_value;
5211 rtx reg = 0;
5212 int partial = 0;
5213 int used = 0;
5214 int i, lower_bound = 0, upper_bound = 0;
5215 int sibcall_failure = 0;
5217 if (TREE_CODE (pval) == ERROR_MARK)
5218 return 1;
5220 /* Push a new temporary level for any temporaries we make for
5221 this argument. */
5222 push_temp_slots ();
5224 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
5226 /* If this is being stored into a pre-allocated, fixed-size, stack area,
5227 save any previous data at that location. */
5228 if (argblock && ! variable_size && arg->stack)
5230 if (ARGS_GROW_DOWNWARD)
5232 /* stack_slot is negative, but we want to index stack_usage_map
5233 with positive values. */
5234 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
5235 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
5236 else
5237 upper_bound = 0;
5239 lower_bound = upper_bound - arg->locate.size.constant;
5241 else
5243 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
5244 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
5245 else
5246 lower_bound = 0;
5248 upper_bound = lower_bound + arg->locate.size.constant;
5251 i = lower_bound;
5252 /* Don't worry about things in the fixed argument area;
5253 it has already been saved. */
5254 if (i < reg_parm_stack_space)
5255 i = reg_parm_stack_space;
5256 while (i < upper_bound && stack_usage_map[i] == 0)
5257 i++;
5259 if (i < upper_bound)
5261 /* We need to make a save area. */
5262 unsigned int size = arg->locate.size.constant * BITS_PER_UNIT;
5263 machine_mode save_mode
5264 = int_mode_for_size (size, 1).else_blk ();
5265 rtx adr = memory_address (save_mode, XEXP (arg->stack_slot, 0));
5266 rtx stack_area = gen_rtx_MEM (save_mode, adr);
5268 if (save_mode == BLKmode)
5270 arg->save_area
5271 = assign_temp (TREE_TYPE (arg->tree_value), 1, 1);
5272 preserve_temp_slots (arg->save_area);
5273 emit_block_move (validize_mem (copy_rtx (arg->save_area)),
5274 stack_area,
5275 GEN_INT (arg->locate.size.constant),
5276 BLOCK_OP_CALL_PARM);
5278 else
5280 arg->save_area = gen_reg_rtx (save_mode);
5281 emit_move_insn (arg->save_area, stack_area);
5287 /* If this isn't going to be placed on both the stack and in registers,
5288 set up the register and number of words. */
5289 if (! arg->pass_on_stack)
5291 if (flags & ECF_SIBCALL)
5292 reg = arg->tail_call_reg;
5293 else
5294 reg = arg->reg;
5295 partial = arg->partial;
5298 /* Being passed entirely in a register. We shouldn't be called in
5299 this case. */
5300 gcc_assert (reg == 0 || partial != 0);
5302 /* If this arg needs special alignment, don't load the registers
5303 here. */
5304 if (arg->n_aligned_regs != 0)
5305 reg = 0;
5307 /* If this is being passed partially in a register, we can't evaluate
5308 it directly into its stack slot. Otherwise, we can. */
5309 if (arg->value == 0)
5311 /* stack_arg_under_construction is nonzero if a function argument is
5312 being evaluated directly into the outgoing argument list and
5313 expand_call must take special action to preserve the argument list
5314 if it is called recursively.
5316 For scalar function arguments stack_usage_map is sufficient to
5317 determine which stack slots must be saved and restored. Scalar
5318 arguments in general have pass_on_stack == 0.
5320 If this argument is initialized by a function which takes the
5321 address of the argument (a C++ constructor or a C function
5322 returning a BLKmode structure), then stack_usage_map is
5323 insufficient and expand_call must push the stack around the
5324 function call. Such arguments have pass_on_stack == 1.
5326 Note that it is always safe to set stack_arg_under_construction,
5327 but this generates suboptimal code if set when not needed. */
5329 if (arg->pass_on_stack)
5330 stack_arg_under_construction++;
5332 arg->value = expand_expr (pval,
5333 (partial
5334 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
5335 ? NULL_RTX : arg->stack,
5336 VOIDmode, EXPAND_STACK_PARM);
5338 /* If we are promoting object (or for any other reason) the mode
5339 doesn't agree, convert the mode. */
5341 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
5342 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
5343 arg->value, arg->unsignedp);
5345 if (arg->pass_on_stack)
5346 stack_arg_under_construction--;
5349 /* Check for overlap with already clobbered argument area. */
5350 if ((flags & ECF_SIBCALL)
5351 && MEM_P (arg->value)
5352 && mem_overlaps_already_clobbered_arg_p (XEXP (arg->value, 0),
5353 arg->locate.size.constant))
5354 sibcall_failure = 1;
5356 /* Don't allow anything left on stack from computation
5357 of argument to alloca. */
5358 if (flags & ECF_MAY_BE_ALLOCA)
5359 do_pending_stack_adjust ();
5361 if (arg->value == arg->stack)
5362 /* If the value is already in the stack slot, we are done. */
5364 else if (arg->mode != BLKmode)
5366 int size;
5367 unsigned int parm_align;
5369 /* Argument is a scalar, not entirely passed in registers.
5370 (If part is passed in registers, arg->partial says how much
5371 and emit_push_insn will take care of putting it there.)
5373 Push it, and if its size is less than the
5374 amount of space allocated to it,
5375 also bump stack pointer by the additional space.
5376 Note that in C the default argument promotions
5377 will prevent such mismatches. */
5379 size = GET_MODE_SIZE (arg->mode);
5380 /* Compute how much space the push instruction will push.
5381 On many machines, pushing a byte will advance the stack
5382 pointer by a halfword. */
5383 #ifdef PUSH_ROUNDING
5384 size = PUSH_ROUNDING (size);
5385 #endif
5386 used = size;
5388 /* Compute how much space the argument should get:
5389 round up to a multiple of the alignment for arguments. */
5390 if (targetm.calls.function_arg_padding (arg->mode, TREE_TYPE (pval))
5391 != PAD_NONE)
5392 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
5393 / (PARM_BOUNDARY / BITS_PER_UNIT))
5394 * (PARM_BOUNDARY / BITS_PER_UNIT));
5396 /* Compute the alignment of the pushed argument. */
5397 parm_align = arg->locate.boundary;
5398 if (targetm.calls.function_arg_padding (arg->mode, TREE_TYPE (pval))
5399 == PAD_DOWNWARD)
5401 int pad = used - size;
5402 if (pad)
5404 unsigned int pad_align = least_bit_hwi (pad) * BITS_PER_UNIT;
5405 parm_align = MIN (parm_align, pad_align);
5409 /* This isn't already where we want it on the stack, so put it there.
5410 This can either be done with push or copy insns. */
5411 if (!emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
5412 parm_align, partial, reg, used - size, argblock,
5413 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
5414 ARGS_SIZE_RTX (arg->locate.alignment_pad), true))
5415 sibcall_failure = 1;
5417 /* Unless this is a partially-in-register argument, the argument is now
5418 in the stack. */
5419 if (partial == 0)
5420 arg->value = arg->stack;
5422 else
5424 /* BLKmode, at least partly to be pushed. */
5426 unsigned int parm_align;
5427 int excess;
5428 rtx size_rtx;
5430 /* Pushing a nonscalar.
5431 If part is passed in registers, PARTIAL says how much
5432 and emit_push_insn will take care of putting it there. */
5434 /* Round its size up to a multiple
5435 of the allocation unit for arguments. */
5437 if (arg->locate.size.var != 0)
5439 excess = 0;
5440 size_rtx = ARGS_SIZE_RTX (arg->locate.size);
5442 else
5444 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
5445 for BLKmode is careful to avoid it. */
5446 excess = (arg->locate.size.constant
5447 - int_size_in_bytes (TREE_TYPE (pval))
5448 + partial);
5449 size_rtx = expand_expr (size_in_bytes (TREE_TYPE (pval)),
5450 NULL_RTX, TYPE_MODE (sizetype),
5451 EXPAND_NORMAL);
5454 parm_align = arg->locate.boundary;
5456 /* When an argument is padded down, the block is aligned to
5457 PARM_BOUNDARY, but the actual argument isn't. */
5458 if (targetm.calls.function_arg_padding (arg->mode, TREE_TYPE (pval))
5459 == PAD_DOWNWARD)
5461 if (arg->locate.size.var)
5462 parm_align = BITS_PER_UNIT;
5463 else if (excess)
5465 unsigned int excess_align = least_bit_hwi (excess) * BITS_PER_UNIT;
5466 parm_align = MIN (parm_align, excess_align);
5470 if ((flags & ECF_SIBCALL) && MEM_P (arg->value))
5472 /* emit_push_insn might not work properly if arg->value and
5473 argblock + arg->locate.offset areas overlap. */
5474 rtx x = arg->value;
5475 int i = 0;
5477 if (XEXP (x, 0) == crtl->args.internal_arg_pointer
5478 || (GET_CODE (XEXP (x, 0)) == PLUS
5479 && XEXP (XEXP (x, 0), 0) ==
5480 crtl->args.internal_arg_pointer
5481 && CONST_INT_P (XEXP (XEXP (x, 0), 1))))
5483 if (XEXP (x, 0) != crtl->args.internal_arg_pointer)
5484 i = INTVAL (XEXP (XEXP (x, 0), 1));
5486 /* arg.locate doesn't contain the pretend_args_size offset,
5487 it's part of argblock. Ensure we don't count it in I. */
5488 if (STACK_GROWS_DOWNWARD)
5489 i -= crtl->args.pretend_args_size;
5490 else
5491 i += crtl->args.pretend_args_size;
5493 /* expand_call should ensure this. */
5494 gcc_assert (!arg->locate.offset.var
5495 && arg->locate.size.var == 0
5496 && CONST_INT_P (size_rtx));
5498 if (arg->locate.offset.constant > i)
5500 if (arg->locate.offset.constant < i + INTVAL (size_rtx))
5501 sibcall_failure = 1;
5503 else if (arg->locate.offset.constant < i)
5505 /* Use arg->locate.size.constant instead of size_rtx
5506 because we only care about the part of the argument
5507 on the stack. */
5508 if (i < (arg->locate.offset.constant
5509 + arg->locate.size.constant))
5510 sibcall_failure = 1;
5512 else
5514 /* Even though they appear to be at the same location,
5515 if part of the outgoing argument is in registers,
5516 they aren't really at the same location. Check for
5517 this by making sure that the incoming size is the
5518 same as the outgoing size. */
5519 if (arg->locate.size.constant != INTVAL (size_rtx))
5520 sibcall_failure = 1;
5525 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
5526 parm_align, partial, reg, excess, argblock,
5527 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
5528 ARGS_SIZE_RTX (arg->locate.alignment_pad), false);
5530 /* Unless this is a partially-in-register argument, the argument is now
5531 in the stack.
5533 ??? Unlike the case above, in which we want the actual
5534 address of the data, so that we can load it directly into a
5535 register, here we want the address of the stack slot, so that
5536 it's properly aligned for word-by-word copying or something
5537 like that. It's not clear that this is always correct. */
5538 if (partial == 0)
5539 arg->value = arg->stack_slot;
5542 if (arg->reg && GET_CODE (arg->reg) == PARALLEL)
5544 tree type = TREE_TYPE (arg->tree_value);
5545 arg->parallel_value
5546 = emit_group_load_into_temps (arg->reg, arg->value, type,
5547 int_size_in_bytes (type));
5550 /* Mark all slots this store used. */
5551 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL)
5552 && argblock && ! variable_size && arg->stack)
5553 for (i = lower_bound; i < upper_bound; i++)
5554 stack_usage_map[i] = 1;
5556 /* Once we have pushed something, pops can't safely
5557 be deferred during the rest of the arguments. */
5558 NO_DEFER_POP;
5560 /* Free any temporary slots made in processing this argument. */
5561 pop_temp_slots ();
5563 return sibcall_failure;
5566 /* Nonzero if we do not know how to pass TYPE solely in registers. */
5568 bool
5569 must_pass_in_stack_var_size (machine_mode mode ATTRIBUTE_UNUSED,
5570 const_tree type)
5572 if (!type)
5573 return false;
5575 /* If the type has variable size... */
5576 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
5577 return true;
5579 /* If the type is marked as addressable (it is required
5580 to be constructed into the stack)... */
5581 if (TREE_ADDRESSABLE (type))
5582 return true;
5584 return false;
5587 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
5588 takes trailing padding of a structure into account. */
5589 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
5591 bool
5592 must_pass_in_stack_var_size_or_pad (machine_mode mode, const_tree type)
5594 if (!type)
5595 return false;
5597 /* If the type has variable size... */
5598 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
5599 return true;
5601 /* If the type is marked as addressable (it is required
5602 to be constructed into the stack)... */
5603 if (TREE_ADDRESSABLE (type))
5604 return true;
5606 /* If the padding and mode of the type is such that a copy into
5607 a register would put it into the wrong part of the register. */
5608 if (mode == BLKmode
5609 && int_size_in_bytes (type) % (PARM_BOUNDARY / BITS_PER_UNIT)
5610 && (targetm.calls.function_arg_padding (mode, type)
5611 == (BYTES_BIG_ENDIAN ? PAD_UPWARD : PAD_DOWNWARD)))
5612 return true;
5614 return false;
5617 /* Tell the garbage collector about GTY markers in this source file. */
5618 #include "gt-calls.h"