1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998
3 1999, 2000, 2001 Free Software Foundation, Inc.
5 This file is part of GNU CC.
7 GNU CC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GNU CC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU CC; see the file COPYING. If not, write to
19 the Free Software Foundation, 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
36 #if !defined FUNCTION_OK_FOR_SIBCALL
37 #define FUNCTION_OK_FOR_SIBCALL(DECL) 1
40 #if !defined PREFERRED_STACK_BOUNDARY && defined STACK_BOUNDARY
41 #define PREFERRED_STACK_BOUNDARY STACK_BOUNDARY
44 /* Decide whether a function's arguments should be processed
45 from first to last or from last to first.
47 They should if the stack and args grow in opposite directions, but
48 only if we have push insns. */
52 #if defined (STACK_GROWS_DOWNWARD) != defined (ARGS_GROW_DOWNWARD)
53 #define PUSH_ARGS_REVERSED PUSH_ARGS
58 #ifndef PUSH_ARGS_REVERSED
59 #define PUSH_ARGS_REVERSED 0
62 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
63 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
65 /* Data structure and subroutines used within expand_call. */
69 /* Tree node for this argument. */
71 /* Mode for value; TYPE_MODE unless promoted. */
72 enum machine_mode mode;
73 /* Current RTL value for argument, or 0 if it isn't precomputed. */
75 /* Initially-compute RTL value for argument; only for const functions. */
77 /* Register to pass this argument in, 0 if passed on stack, or an
78 PARALLEL if the arg is to be copied into multiple non-contiguous
81 /* Register to pass this argument in when generating tail call sequence.
82 This is not the same register as for normal calls on machines with
85 /* If REG was promoted from the actual mode of the argument expression,
86 indicates whether the promotion is sign- or zero-extended. */
88 /* Number of registers to use. 0 means put the whole arg in registers.
89 Also 0 if not passed in registers. */
91 /* Non-zero if argument must be passed on stack.
92 Note that some arguments may be passed on the stack
93 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
94 pass_on_stack identifies arguments that *cannot* go in registers. */
96 /* Offset of this argument from beginning of stack-args. */
97 struct args_size offset;
98 /* Similar, but offset to the start of the stack slot. Different from
99 OFFSET if this arg pads downward. */
100 struct args_size slot_offset;
101 /* Size of this argument on the stack, rounded up for any padding it gets,
102 parts of the argument passed in registers do not count.
103 If REG_PARM_STACK_SPACE is defined, then register parms
104 are counted here as well. */
105 struct args_size size;
106 /* Location on the stack at which parameter should be stored. The store
107 has already been done if STACK == VALUE. */
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 FUNCTION_ARG_BOUNDARY. */
113 /* Place that this stack area has been saved, if needed. */
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. */
121 /* The amount that the stack pointer needs to be adjusted to
122 force alignment for the next argument. */
123 struct args_size alignment_pad;
126 /* A vector of one char per byte of stack space. A byte if non-zero if
127 the corresponding stack location has been used.
128 This vector is used to prevent a function call within an argument from
129 clobbering any stack already set up. */
130 static char *stack_usage_map;
132 /* Size of STACK_USAGE_MAP. */
133 static int highest_outgoing_arg_in_use;
135 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
136 stack location's tail call argument has been already stored into the stack.
137 This bitmap is used to prevent sibling call optimization if function tries
138 to use parent's incoming argument slots when they have been already
139 overwritten with tail call arguments. */
140 static sbitmap stored_args_map;
142 /* stack_arg_under_construction is nonzero when an argument may be
143 initialized with a constructor call (including a C function that
144 returns a BLKmode struct) and expand_call must take special action
145 to make sure the object being constructed does not overlap the
146 argument list for the constructor call. */
147 int stack_arg_under_construction;
149 static int calls_function PARAMS ((tree, int));
150 static int calls_function_1 PARAMS ((tree, int));
152 /* Nonzero if this is a call to a `const' function. */
154 /* Nonzero if this is a call to a `volatile' function. */
155 #define ECF_NORETURN 2
156 /* Nonzero if this is a call to malloc or a related function. */
158 /* Nonzero if it is plausible that this is a call to alloca. */
159 #define ECF_MAY_BE_ALLOCA 8
160 /* Nonzero if this is a call to a function that won't throw an exception. */
161 #define ECF_NOTHROW 16
162 /* Nonzero if this is a call to setjmp or a related function. */
163 #define ECF_RETURNS_TWICE 32
164 /* Nonzero if this is a call to `longjmp'. */
165 #define ECF_LONGJMP 64
166 /* Nonzero if this is a syscall that makes a new process in the image of
168 #define ECF_FORK_OR_EXEC 128
169 #define ECF_SIBCALL 256
170 /* Nonzero if this is a call to "pure" function (like const function,
171 but may read memory. */
173 /* Nonzero if this is a call to a function that returns with the stack
174 pointer depressed. */
175 #define ECF_SP_DEPRESSED 1024
177 static void emit_call_1 PARAMS ((rtx, tree, tree, HOST_WIDE_INT,
178 HOST_WIDE_INT, HOST_WIDE_INT, rtx,
179 rtx, int, rtx, int));
180 static void precompute_register_parameters PARAMS ((int,
183 static int store_one_arg PARAMS ((struct arg_data *, rtx, int, int,
185 static void store_unaligned_arguments_into_pseudos PARAMS ((struct arg_data *,
187 static int finalize_must_preallocate PARAMS ((int, int,
189 struct args_size *));
190 static void precompute_arguments PARAMS ((int, int,
192 static int compute_argument_block_size PARAMS ((int,
195 static void initialize_argument_information PARAMS ((int,
202 static void compute_argument_addresses PARAMS ((struct arg_data *,
204 static rtx rtx_for_function_call PARAMS ((tree, tree));
205 static void load_register_parameters PARAMS ((struct arg_data *,
207 static rtx emit_library_call_value_1 PARAMS ((int, rtx, rtx,
211 static int special_function_p PARAMS ((tree, int));
212 static int flags_from_decl_or_type PARAMS ((tree));
213 static rtx try_to_integrate PARAMS ((tree, tree, rtx,
215 static int check_sibcall_argument_overlap_1 PARAMS ((rtx));
216 static int check_sibcall_argument_overlap PARAMS ((rtx, struct arg_data *));
218 static int combine_pending_stack_adjustment_and_call
219 PARAMS ((int, struct args_size *, int));
221 #ifdef REG_PARM_STACK_SPACE
222 static rtx save_fixed_argument_area PARAMS ((int, rtx, int *, int *));
223 static void restore_fixed_argument_area PARAMS ((rtx, rtx, int, int));
226 /* If WHICH is 1, return 1 if EXP contains a call to the built-in function
229 If WHICH is 0, return 1 if EXP contains a call to any function.
230 Actually, we only need return 1 if evaluating EXP would require pushing
231 arguments on the stack, but that is too difficult to compute, so we just
232 assume any function call might require the stack. */
234 static tree calls_function_save_exprs;
237 calls_function (exp, which)
243 calls_function_save_exprs = 0;
244 val = calls_function_1 (exp, which);
245 calls_function_save_exprs = 0;
249 /* Recursive function to do the work of above function. */
252 calls_function_1 (exp, which)
257 enum tree_code code = TREE_CODE (exp);
258 int class = TREE_CODE_CLASS (code);
259 int length = first_rtl_op (code);
261 /* If this code is language-specific, we don't know what it will do. */
262 if ((int) code >= NUM_TREE_CODES)
270 else if ((TREE_CODE (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))
272 && (TYPE_RETURNS_STACK_DEPRESSED
273 (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))))
275 else if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
276 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
278 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp, 0), 0),
280 & ECF_MAY_BE_ALLOCA))
289 for (tem = CONSTRUCTOR_ELTS (exp); tem != 0; tem = TREE_CHAIN (tem))
290 if (calls_function_1 (TREE_VALUE (tem), which))
297 if (SAVE_EXPR_RTL (exp) != 0)
299 if (value_member (exp, calls_function_save_exprs))
301 calls_function_save_exprs = tree_cons (NULL_TREE, exp,
302 calls_function_save_exprs);
303 return (TREE_OPERAND (exp, 0) != 0
304 && calls_function_1 (TREE_OPERAND (exp, 0), which));
309 register tree subblock;
311 for (local = BLOCK_VARS (exp); local; local = TREE_CHAIN (local))
312 if (DECL_INITIAL (local) != 0
313 && calls_function_1 (DECL_INITIAL (local), which))
316 for (subblock = BLOCK_SUBBLOCKS (exp);
318 subblock = TREE_CHAIN (subblock))
319 if (calls_function_1 (subblock, which))
325 for (; exp != 0; exp = TREE_CHAIN (exp))
326 if (calls_function_1 (TREE_VALUE (exp), which))
334 /* Only expressions, references, and blocks can contain calls. */
335 if (! IS_EXPR_CODE_CLASS (class) && class != 'r' && class != 'b')
338 for (i = 0; i < length; i++)
339 if (TREE_OPERAND (exp, i) != 0
340 && calls_function_1 (TREE_OPERAND (exp, i), which))
346 /* Force FUNEXP into a form suitable for the address of a CALL,
347 and return that as an rtx. Also load the static chain register
348 if FNDECL is a nested function.
350 CALL_FUSAGE points to a variable holding the prospective
351 CALL_INSN_FUNCTION_USAGE information. */
354 prepare_call_address (funexp, fndecl, call_fusage, reg_parm_seen)
360 rtx static_chain_value = 0;
362 funexp = protect_from_queue (funexp, 0);
365 /* Get possible static chain value for nested function in C. */
366 static_chain_value = lookup_static_chain (fndecl);
368 /* Make a valid memory address and copy constants thru pseudo-regs,
369 but not for a constant address if -fno-function-cse. */
370 if (GET_CODE (funexp) != SYMBOL_REF)
371 /* If we are using registers for parameters, force the
372 function address into a register now. */
373 funexp = ((SMALL_REGISTER_CLASSES && reg_parm_seen)
374 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
375 : memory_address (FUNCTION_MODE, funexp));
378 #ifndef NO_FUNCTION_CSE
379 if (optimize && ! flag_no_function_cse)
380 #ifdef NO_RECURSIVE_FUNCTION_CSE
381 if (fndecl != current_function_decl)
383 funexp = force_reg (Pmode, funexp);
387 if (static_chain_value != 0)
389 emit_move_insn (static_chain_rtx, static_chain_value);
391 if (GET_CODE (static_chain_rtx) == REG)
392 use_reg (call_fusage, static_chain_rtx);
398 /* Generate instructions to call function FUNEXP,
399 and optionally pop the results.
400 The CALL_INSN is the first insn generated.
402 FNDECL is the declaration node of the function. This is given to the
403 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
405 FUNTYPE is the data type of the function. This is given to the macro
406 RETURN_POPS_ARGS to determine whether this function pops its own args.
407 We used to allow an identifier for library functions, but that doesn't
408 work when the return type is an aggregate type and the calling convention
409 says that the pointer to this aggregate is to be popped by the callee.
411 STACK_SIZE is the number of bytes of arguments on the stack,
412 ROUNDED_STACK_SIZE is that number rounded up to
413 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
414 both to put into the call insn and to generate explicit popping
417 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
418 It is zero if this call doesn't want a structure value.
420 NEXT_ARG_REG is the rtx that results from executing
421 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
422 just after all the args have had their registers assigned.
423 This could be whatever you like, but normally it is the first
424 arg-register beyond those used for args in this call,
425 or 0 if all the arg-registers are used in this call.
426 It is passed on to `gen_call' so you can put this info in the call insn.
428 VALREG is a hard register in which a value is returned,
429 or 0 if the call does not return a value.
431 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
432 the args to this call were processed.
433 We restore `inhibit_defer_pop' to that value.
435 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
436 denote registers used by the called function. */
439 emit_call_1 (funexp, fndecl, funtype, stack_size, rounded_stack_size,
440 struct_value_size, next_arg_reg, valreg, old_inhibit_defer_pop,
441 call_fusage, ecf_flags)
443 tree fndecl ATTRIBUTE_UNUSED;
444 tree funtype ATTRIBUTE_UNUSED;
445 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED;
446 HOST_WIDE_INT rounded_stack_size;
447 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED;
450 int old_inhibit_defer_pop;
454 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
456 int already_popped = 0;
457 HOST_WIDE_INT n_popped = RETURN_POPS_ARGS (fndecl, funtype, stack_size);
458 #if defined (HAVE_call) && defined (HAVE_call_value)
459 rtx struct_value_size_rtx;
460 struct_value_size_rtx = GEN_INT (struct_value_size);
463 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
464 and we don't want to load it into a register as an optimization,
465 because prepare_call_address already did it if it should be done. */
466 if (GET_CODE (funexp) != SYMBOL_REF)
467 funexp = memory_address (FUNCTION_MODE, funexp);
469 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
470 if ((ecf_flags & ECF_SIBCALL)
471 && HAVE_sibcall_pop && HAVE_sibcall_value_pop
472 && (n_popped > 0 || stack_size == 0))
474 rtx n_pop = GEN_INT (n_popped));
477 /* If this subroutine pops its own args, record that in the call insn
478 if possible, for the sake of frame pointer elimination. */
481 pat = GEN_SIBCALL_VALUE_POP (valreg,
482 gen_rtx_MEM (FUNCTION_MODE, funexp),
483 rounded_stack_size_rtx, next_arg_reg,
486 pat = GEN_SIBCALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
487 rounded_stack_size_rtx, next_arg_reg, n_pop);
489 emit_call_insn (pat);
495 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
496 /* If the target has "call" or "call_value" insns, then prefer them
497 if no arguments are actually popped. If the target does not have
498 "call" or "call_value" insns, then we must use the popping versions
499 even if the call has no arguments to pop. */
500 #if defined (HAVE_call) && defined (HAVE_call_value)
501 if (HAVE_call && HAVE_call_value && HAVE_call_pop && HAVE_call_value_pop
502 && n_popped > 0 && ! (ecf_flags & ECF_SP_DEPRESSED))
504 if (HAVE_call_pop && HAVE_call_value_pop)
507 rtx n_pop = GEN_INT (n_popped);
510 /* If this subroutine pops its own args, record that in the call insn
511 if possible, for the sake of frame pointer elimination. */
514 pat = GEN_CALL_VALUE_POP (valreg,
515 gen_rtx_MEM (FUNCTION_MODE, funexp),
516 rounded_stack_size_rtx, next_arg_reg, n_pop);
518 pat = GEN_CALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
519 rounded_stack_size_rtx, next_arg_reg, n_pop);
521 emit_call_insn (pat);
527 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
528 if ((ecf_flags & ECF_SIBCALL)
529 && HAVE_sibcall && HAVE_sibcall_value)
532 emit_call_insn (GEN_SIBCALL_VALUE (valreg,
533 gen_rtx_MEM (FUNCTION_MODE, funexp),
534 rounded_stack_size_rtx,
535 next_arg_reg, NULL_RTX));
537 emit_call_insn (GEN_SIBCALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
538 rounded_stack_size_rtx, next_arg_reg,
539 struct_value_size_rtx));
544 #if defined (HAVE_call) && defined (HAVE_call_value)
545 if (HAVE_call && HAVE_call_value)
548 emit_call_insn (GEN_CALL_VALUE (valreg,
549 gen_rtx_MEM (FUNCTION_MODE, funexp),
550 rounded_stack_size_rtx, next_arg_reg,
553 emit_call_insn (GEN_CALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
554 rounded_stack_size_rtx, next_arg_reg,
555 struct_value_size_rtx));
561 /* Find the CALL insn we just emitted. */
562 for (call_insn = get_last_insn ();
563 call_insn && GET_CODE (call_insn) != CALL_INSN;
564 call_insn = PREV_INSN (call_insn))
570 /* Mark memory as used for "pure" function call. */
571 if (ecf_flags & ECF_PURE)
573 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
574 gen_rtx_USE (VOIDmode,
575 gen_rtx_MEM (BLKmode,
576 gen_rtx_SCRATCH (VOIDmode))), call_fusage);
579 /* Put the register usage information on the CALL. If there is already
580 some usage information, put ours at the end. */
581 if (CALL_INSN_FUNCTION_USAGE (call_insn))
585 for (link = CALL_INSN_FUNCTION_USAGE (call_insn); XEXP (link, 1) != 0;
586 link = XEXP (link, 1))
589 XEXP (link, 1) = call_fusage;
592 CALL_INSN_FUNCTION_USAGE (call_insn) = call_fusage;
594 /* If this is a const call, then set the insn's unchanging bit. */
595 if (ecf_flags & (ECF_CONST | ECF_PURE))
596 CONST_CALL_P (call_insn) = 1;
598 /* If this call can't throw, attach a REG_EH_REGION reg note to that
600 if (ecf_flags & ECF_NOTHROW)
601 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_EH_REGION, const0_rtx,
602 REG_NOTES (call_insn));
604 if (ecf_flags & ECF_NORETURN)
605 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_NORETURN, const0_rtx,
606 REG_NOTES (call_insn));
608 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
610 /* Restore this now, so that we do defer pops for this call's args
611 if the context of the call as a whole permits. */
612 inhibit_defer_pop = old_inhibit_defer_pop;
617 CALL_INSN_FUNCTION_USAGE (call_insn)
618 = gen_rtx_EXPR_LIST (VOIDmode,
619 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
620 CALL_INSN_FUNCTION_USAGE (call_insn));
621 rounded_stack_size -= n_popped;
622 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
623 stack_pointer_delta -= n_popped;
626 if (!ACCUMULATE_OUTGOING_ARGS)
628 /* If returning from the subroutine does not automatically pop the args,
629 we need an instruction to pop them sooner or later.
630 Perhaps do it now; perhaps just record how much space to pop later.
632 If returning from the subroutine does pop the args, indicate that the
633 stack pointer will be changed. */
635 if (rounded_stack_size != 0 && ! (ecf_flags & ECF_SP_DEPRESSED))
637 if (flag_defer_pop && inhibit_defer_pop == 0
638 && ! (ecf_flags & (ECF_CONST | ECF_PURE)))
639 pending_stack_adjust += rounded_stack_size;
641 adjust_stack (rounded_stack_size_rtx);
644 /* When we accumulate outgoing args, we must avoid any stack manipulations.
645 Restore the stack pointer to its original value now. Usually
646 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
647 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
648 popping variants of functions exist as well.
650 ??? We may optimize similar to defer_pop above, but it is
651 probably not worthwhile.
653 ??? It will be worthwhile to enable combine_stack_adjustments even for
656 anti_adjust_stack (GEN_INT (n_popped));
659 /* Determine if the function identified by NAME and FNDECL is one with
660 special properties we wish to know about.
662 For example, if the function might return more than one time (setjmp), then
663 set RETURNS_TWICE to a nonzero value.
665 Similarly set LONGJMP for if the function is in the longjmp family.
667 Set MALLOC for any of the standard memory allocation functions which
668 allocate from the heap.
670 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
671 space from the stack such as alloca. */
674 special_function_p (fndecl, flags)
678 if (! (flags & ECF_MALLOC)
679 && fndecl && DECL_NAME (fndecl)
680 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 17
681 /* Exclude functions not at the file scope, or not `extern',
682 since they are not the magic functions we would otherwise
684 && DECL_CONTEXT (fndecl) == NULL_TREE && TREE_PUBLIC (fndecl))
686 const char *name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
687 const char *tname = name;
689 /* We assume that alloca will always be called by name. It
690 makes no sense to pass it as a pointer-to-function to
691 anything that does not understand its behavior. */
692 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
694 && ! strcmp (name, "alloca"))
695 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
697 && ! strcmp (name, "__builtin_alloca"))))
698 flags |= ECF_MAY_BE_ALLOCA;
700 /* Disregard prefix _, __ or __x. */
703 if (name[1] == '_' && name[2] == 'x')
705 else if (name[1] == '_')
714 && (! strcmp (tname, "setjmp")
715 || ! strcmp (tname, "setjmp_syscall")))
717 && ! strcmp (tname, "sigsetjmp"))
719 && ! strcmp (tname, "savectx")))
720 flags |= ECF_RETURNS_TWICE;
723 && ! strcmp (tname, "siglongjmp"))
724 flags |= ECF_LONGJMP;
726 else if ((tname[0] == 'q' && tname[1] == 's'
727 && ! strcmp (tname, "qsetjmp"))
728 || (tname[0] == 'v' && tname[1] == 'f'
729 && ! strcmp (tname, "vfork")))
730 flags |= ECF_RETURNS_TWICE;
732 else if (tname[0] == 'l' && tname[1] == 'o'
733 && ! strcmp (tname, "longjmp"))
734 flags |= ECF_LONGJMP;
736 else if ((tname[0] == 'f' && tname[1] == 'o'
737 && ! strcmp (tname, "fork"))
738 /* Linux specific: __clone. check NAME to insist on the
739 leading underscores, to avoid polluting the ISO / POSIX
741 || (name[0] == '_' && name[1] == '_'
742 && ! strcmp (tname, "clone"))
743 || (tname[0] == 'e' && tname[1] == 'x' && tname[2] == 'e'
744 && tname[3] == 'c' && (tname[4] == 'l' || tname[4] == 'v')
746 || ((tname[5] == 'p' || tname[5] == 'e')
747 && tname[6] == '\0'))))
748 flags |= ECF_FORK_OR_EXEC;
750 /* Do not add any more malloc-like functions to this list,
751 instead mark them as malloc functions using the malloc attribute.
752 Note, realloc is not suitable for attribute malloc since
753 it may return the same address across multiple calls.
754 C++ operator new is not suitable because it is not required
755 to return a unique pointer; indeed, the standard placement new
756 just returns its argument. */
757 else if (TYPE_MODE (TREE_TYPE (TREE_TYPE (fndecl))) == Pmode
758 && (! strcmp (tname, "malloc")
759 || ! strcmp (tname, "calloc")
760 || ! strcmp (tname, "strdup")))
766 /* Return nonzero when tree represent call to longjmp. */
769 setjmp_call_p (fndecl)
772 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
775 /* Detect flags (function attributes) from the function type node. */
778 flags_from_decl_or_type (exp)
783 /* ??? We can't set IS_MALLOC for function types? */
786 /* The function exp may have the `malloc' attribute. */
787 if (DECL_P (exp) && DECL_IS_MALLOC (exp))
790 /* The function exp may have the `pure' attribute. */
791 if (DECL_P (exp) && DECL_IS_PURE (exp))
794 if (TREE_NOTHROW (exp))
795 flags |= ECF_NOTHROW;
798 if (TREE_READONLY (exp) && ! TREE_THIS_VOLATILE (exp))
801 if (TREE_THIS_VOLATILE (exp))
802 flags |= ECF_NORETURN;
807 /* Precompute all register parameters as described by ARGS, storing values
808 into fields within the ARGS array.
810 NUM_ACTUALS indicates the total number elements in the ARGS array.
812 Set REG_PARM_SEEN if we encounter a register parameter. */
815 precompute_register_parameters (num_actuals, args, reg_parm_seen)
817 struct arg_data *args;
824 for (i = 0; i < num_actuals; i++)
825 if (args[i].reg != 0 && ! args[i].pass_on_stack)
829 if (args[i].value == 0)
832 args[i].value = expand_expr (args[i].tree_value, NULL_RTX,
834 preserve_temp_slots (args[i].value);
837 /* ANSI doesn't require a sequence point here,
838 but PCC has one, so this will avoid some problems. */
842 /* If we are to promote the function arg to a wider mode,
845 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
847 = convert_modes (args[i].mode,
848 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
849 args[i].value, args[i].unsignedp);
851 /* If the value is expensive, and we are inside an appropriately
852 short loop, put the value into a pseudo and then put the pseudo
855 For small register classes, also do this if this call uses
856 register parameters. This is to avoid reload conflicts while
857 loading the parameters registers. */
859 if ((! (GET_CODE (args[i].value) == REG
860 || (GET_CODE (args[i].value) == SUBREG
861 && GET_CODE (SUBREG_REG (args[i].value)) == REG)))
862 && args[i].mode != BLKmode
863 && rtx_cost (args[i].value, SET) > COSTS_N_INSNS (1)
864 && ((SMALL_REGISTER_CLASSES && *reg_parm_seen)
865 || preserve_subexpressions_p ()))
866 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
870 #ifdef REG_PARM_STACK_SPACE
872 /* The argument list is the property of the called routine and it
873 may clobber it. If the fixed area has been used for previous
874 parameters, we must save and restore it. */
877 save_fixed_argument_area (reg_parm_stack_space, argblock,
878 low_to_save, high_to_save)
879 int reg_parm_stack_space;
885 rtx save_area = NULL_RTX;
887 /* Compute the boundary of the that needs to be saved, if any. */
888 #ifdef ARGS_GROW_DOWNWARD
889 for (i = 0; i < reg_parm_stack_space + 1; i++)
891 for (i = 0; i < reg_parm_stack_space; i++)
894 if (i >= highest_outgoing_arg_in_use
895 || stack_usage_map[i] == 0)
898 if (*low_to_save == -1)
904 if (*low_to_save >= 0)
906 int num_to_save = *high_to_save - *low_to_save + 1;
907 enum machine_mode save_mode
908 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
911 /* If we don't have the required alignment, must do this in BLKmode. */
912 if ((*low_to_save & (MIN (GET_MODE_SIZE (save_mode),
913 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
916 #ifdef ARGS_GROW_DOWNWARD
918 = gen_rtx_MEM (save_mode,
919 memory_address (save_mode,
920 plus_constant (argblock,
923 stack_area = gen_rtx_MEM (save_mode,
924 memory_address (save_mode,
925 plus_constant (argblock,
928 if (save_mode == BLKmode)
930 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
931 /* Cannot use emit_block_move here because it can be done by a
932 library call which in turn gets into this place again and deadly
933 infinite recursion happens. */
934 move_by_pieces (validize_mem (save_area), stack_area, num_to_save,
939 save_area = gen_reg_rtx (save_mode);
940 emit_move_insn (save_area, stack_area);
947 restore_fixed_argument_area (save_area, argblock, high_to_save, low_to_save)
953 enum machine_mode save_mode = GET_MODE (save_area);
954 #ifdef ARGS_GROW_DOWNWARD
956 = gen_rtx_MEM (save_mode,
957 memory_address (save_mode,
958 plus_constant (argblock,
962 = gen_rtx_MEM (save_mode,
963 memory_address (save_mode,
964 plus_constant (argblock,
968 if (save_mode != BLKmode)
969 emit_move_insn (stack_area, save_area);
971 /* Cannot use emit_block_move here because it can be done by a library
972 call which in turn gets into this place again and deadly infinite
973 recursion happens. */
974 move_by_pieces (stack_area, validize_mem (save_area),
975 high_to_save - low_to_save + 1, PARM_BOUNDARY);
979 /* If any elements in ARGS refer to parameters that are to be passed in
980 registers, but not in memory, and whose alignment does not permit a
981 direct copy into registers. Copy the values into a group of pseudos
982 which we will later copy into the appropriate hard registers.
984 Pseudos for each unaligned argument will be stored into the array
985 args[argnum].aligned_regs. The caller is responsible for deallocating
986 the aligned_regs array if it is nonzero. */
989 store_unaligned_arguments_into_pseudos (args, num_actuals)
990 struct arg_data *args;
995 for (i = 0; i < num_actuals; i++)
996 if (args[i].reg != 0 && ! args[i].pass_on_stack
997 && args[i].mode == BLKmode
998 && (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
999 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1001 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1002 int big_endian_correction = 0;
1004 args[i].n_aligned_regs
1005 = args[i].partial ? args[i].partial
1006 : (bytes + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
1008 args[i].aligned_regs = (rtx *) xmalloc (sizeof (rtx)
1009 * args[i].n_aligned_regs);
1011 /* Structures smaller than a word are aligned to the least
1012 significant byte (to the right). On a BYTES_BIG_ENDIAN machine,
1013 this means we must skip the empty high order bytes when
1014 calculating the bit offset. */
1015 if (BYTES_BIG_ENDIAN && bytes < UNITS_PER_WORD)
1016 big_endian_correction = (BITS_PER_WORD - (bytes * BITS_PER_UNIT));
1018 for (j = 0; j < args[i].n_aligned_regs; j++)
1020 rtx reg = gen_reg_rtx (word_mode);
1021 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1022 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
1023 int bitalign = TYPE_ALIGN (TREE_TYPE (args[i].tree_value));
1025 args[i].aligned_regs[j] = reg;
1027 /* There is no need to restrict this code to loading items
1028 in TYPE_ALIGN sized hunks. The bitfield instructions can
1029 load up entire word sized registers efficiently.
1031 ??? This may not be needed anymore.
1032 We use to emit a clobber here but that doesn't let later
1033 passes optimize the instructions we emit. By storing 0 into
1034 the register later passes know the first AND to zero out the
1035 bitfield being set in the register is unnecessary. The store
1036 of 0 will be deleted as will at least the first AND. */
1038 emit_move_insn (reg, const0_rtx);
1040 bytes -= bitsize / BITS_PER_UNIT;
1041 store_bit_field (reg, bitsize, big_endian_correction, word_mode,
1042 extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
1043 word_mode, word_mode, bitalign,
1045 bitalign, BITS_PER_WORD);
1050 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1053 NUM_ACTUALS is the total number of parameters.
1055 N_NAMED_ARGS is the total number of named arguments.
1057 FNDECL is the tree code for the target of this call (if known)
1059 ARGS_SO_FAR holds state needed by the target to know where to place
1062 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1063 for arguments which are passed in registers.
1065 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1066 and may be modified by this routine.
1068 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1069 flags which may may be modified by this routine. */
1072 initialize_argument_information (num_actuals, args, args_size, n_named_args,
1073 actparms, fndecl, args_so_far,
1074 reg_parm_stack_space, old_stack_level,
1075 old_pending_adj, must_preallocate,
1077 int num_actuals ATTRIBUTE_UNUSED;
1078 struct arg_data *args;
1079 struct args_size *args_size;
1080 int n_named_args ATTRIBUTE_UNUSED;
1083 CUMULATIVE_ARGS *args_so_far;
1084 int reg_parm_stack_space;
1085 rtx *old_stack_level;
1086 int *old_pending_adj;
1087 int *must_preallocate;
1090 /* 1 if scanning parms front to back, -1 if scanning back to front. */
1093 /* Count arg position in order args appear. */
1096 struct args_size alignment_pad;
1100 args_size->constant = 0;
1103 /* In this loop, we consider args in the order they are written.
1104 We fill up ARGS from the front or from the back if necessary
1105 so that in any case the first arg to be pushed ends up at the front. */
1107 if (PUSH_ARGS_REVERSED)
1109 i = num_actuals - 1, inc = -1;
1110 /* In this case, must reverse order of args
1111 so that we compute and push the last arg first. */
1118 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1119 for (p = actparms, argpos = 0; p; p = TREE_CHAIN (p), i += inc, argpos++)
1121 tree type = TREE_TYPE (TREE_VALUE (p));
1123 enum machine_mode mode;
1125 args[i].tree_value = TREE_VALUE (p);
1127 /* Replace erroneous argument with constant zero. */
1128 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1129 args[i].tree_value = integer_zero_node, type = integer_type_node;
1131 /* If TYPE is a transparent union, pass things the way we would
1132 pass the first field of the union. We have already verified that
1133 the modes are the same. */
1134 if (TREE_CODE (type) == UNION_TYPE && TYPE_TRANSPARENT_UNION (type))
1135 type = TREE_TYPE (TYPE_FIELDS (type));
1137 /* Decide where to pass this arg.
1139 args[i].reg is nonzero if all or part is passed in registers.
1141 args[i].partial is nonzero if part but not all is passed in registers,
1142 and the exact value says how many words are passed in registers.
1144 args[i].pass_on_stack is nonzero if the argument must at least be
1145 computed on the stack. It may then be loaded back into registers
1146 if args[i].reg is nonzero.
1148 These decisions are driven by the FUNCTION_... macros and must agree
1149 with those made by function.c. */
1151 /* See if this argument should be passed by invisible reference. */
1152 if ((TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1153 && contains_placeholder_p (TYPE_SIZE (type)))
1154 || TREE_ADDRESSABLE (type)
1155 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1156 || FUNCTION_ARG_PASS_BY_REFERENCE (*args_so_far, TYPE_MODE (type),
1157 type, argpos < n_named_args)
1161 /* If we're compiling a thunk, pass through invisible
1162 references instead of making a copy. */
1163 if (current_function_is_thunk
1164 #ifdef FUNCTION_ARG_CALLEE_COPIES
1165 || (FUNCTION_ARG_CALLEE_COPIES (*args_so_far, TYPE_MODE (type),
1166 type, argpos < n_named_args)
1167 /* If it's in a register, we must make a copy of it too. */
1168 /* ??? Is this a sufficient test? Is there a better one? */
1169 && !(TREE_CODE (args[i].tree_value) == VAR_DECL
1170 && REG_P (DECL_RTL (args[i].tree_value)))
1171 && ! TREE_ADDRESSABLE (type))
1175 /* C++ uses a TARGET_EXPR to indicate that we want to make a
1176 new object from the argument. If we are passing by
1177 invisible reference, the callee will do that for us, so we
1178 can strip off the TARGET_EXPR. This is not always safe,
1179 but it is safe in the only case where this is a useful
1180 optimization; namely, when the argument is a plain object.
1181 In that case, the frontend is just asking the backend to
1182 make a bitwise copy of the argument. */
1184 if (TREE_CODE (args[i].tree_value) == TARGET_EXPR
1185 && (DECL_P (TREE_OPERAND (args[i].tree_value, 1)))
1186 && ! REG_P (DECL_RTL (TREE_OPERAND (args[i].tree_value, 1))))
1187 args[i].tree_value = TREE_OPERAND (args[i].tree_value, 1);
1189 args[i].tree_value = build1 (ADDR_EXPR,
1190 build_pointer_type (type),
1191 args[i].tree_value);
1192 type = build_pointer_type (type);
1196 /* We make a copy of the object and pass the address to the
1197 function being called. */
1200 if (!COMPLETE_TYPE_P (type)
1201 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1202 || (flag_stack_check && ! STACK_CHECK_BUILTIN
1203 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type),
1204 STACK_CHECK_MAX_VAR_SIZE))))
1206 /* This is a variable-sized object. Make space on the stack
1208 rtx size_rtx = expr_size (TREE_VALUE (p));
1210 if (*old_stack_level == 0)
1212 emit_stack_save (SAVE_BLOCK, old_stack_level, NULL_RTX);
1213 *old_pending_adj = pending_stack_adjust;
1214 pending_stack_adjust = 0;
1217 copy = gen_rtx_MEM (BLKmode,
1218 allocate_dynamic_stack_space
1219 (size_rtx, NULL_RTX, TYPE_ALIGN (type)));
1220 set_mem_attributes (copy, type, 1);
1223 copy = assign_temp (type, 0, 1, 0);
1225 store_expr (args[i].tree_value, copy, 0);
1226 *ecf_flags &= ~(ECF_CONST | ECF_PURE);
1228 args[i].tree_value = build1 (ADDR_EXPR,
1229 build_pointer_type (type),
1230 make_tree (type, copy));
1231 type = build_pointer_type (type);
1235 mode = TYPE_MODE (type);
1236 unsignedp = TREE_UNSIGNED (type);
1238 #ifdef PROMOTE_FUNCTION_ARGS
1239 mode = promote_mode (type, mode, &unsignedp, 1);
1242 args[i].unsignedp = unsignedp;
1243 args[i].mode = mode;
1245 args[i].reg = FUNCTION_ARG (*args_so_far, mode, type,
1246 argpos < n_named_args);
1247 #ifdef FUNCTION_INCOMING_ARG
1248 /* If this is a sibling call and the machine has register windows, the
1249 register window has to be unwinded before calling the routine, so
1250 arguments have to go into the incoming registers. */
1251 args[i].tail_call_reg = FUNCTION_INCOMING_ARG (*args_so_far, mode, type,
1252 argpos < n_named_args);
1254 args[i].tail_call_reg = args[i].reg;
1257 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1260 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far, mode, type,
1261 argpos < n_named_args);
1264 args[i].pass_on_stack = MUST_PASS_IN_STACK (mode, type);
1266 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1267 it means that we are to pass this arg in the register(s) designated
1268 by the PARALLEL, but also to pass it in the stack. */
1269 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1270 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1271 args[i].pass_on_stack = 1;
1273 /* If this is an addressable type, we must preallocate the stack
1274 since we must evaluate the object into its final location.
1276 If this is to be passed in both registers and the stack, it is simpler
1278 if (TREE_ADDRESSABLE (type)
1279 || (args[i].pass_on_stack && args[i].reg != 0))
1280 *must_preallocate = 1;
1282 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1283 we cannot consider this function call constant. */
1284 if (TREE_ADDRESSABLE (type))
1285 *ecf_flags &= ~(ECF_CONST | ECF_PURE);
1287 /* Compute the stack-size of this argument. */
1288 if (args[i].reg == 0 || args[i].partial != 0
1289 || reg_parm_stack_space > 0
1290 || args[i].pass_on_stack)
1291 locate_and_pad_parm (mode, type,
1292 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1297 fndecl, args_size, &args[i].offset,
1298 &args[i].size, &alignment_pad);
1300 #ifndef ARGS_GROW_DOWNWARD
1301 args[i].slot_offset = *args_size;
1304 args[i].alignment_pad = alignment_pad;
1306 /* If a part of the arg was put into registers,
1307 don't include that part in the amount pushed. */
1308 if (reg_parm_stack_space == 0 && ! args[i].pass_on_stack)
1309 args[i].size.constant -= ((args[i].partial * UNITS_PER_WORD)
1310 / (PARM_BOUNDARY / BITS_PER_UNIT)
1311 * (PARM_BOUNDARY / BITS_PER_UNIT));
1313 /* Update ARGS_SIZE, the total stack space for args so far. */
1315 args_size->constant += args[i].size.constant;
1316 if (args[i].size.var)
1318 ADD_PARM_SIZE (*args_size, args[i].size.var);
1321 /* Since the slot offset points to the bottom of the slot,
1322 we must record it after incrementing if the args grow down. */
1323 #ifdef ARGS_GROW_DOWNWARD
1324 args[i].slot_offset = *args_size;
1326 args[i].slot_offset.constant = -args_size->constant;
1328 SUB_PARM_SIZE (args[i].slot_offset, args_size->var);
1331 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1332 have been used, etc. */
1334 FUNCTION_ARG_ADVANCE (*args_so_far, TYPE_MODE (type), type,
1335 argpos < n_named_args);
1339 /* Update ARGS_SIZE to contain the total size for the argument block.
1340 Return the original constant component of the argument block's size.
1342 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1343 for arguments passed in registers. */
1346 compute_argument_block_size (reg_parm_stack_space, args_size,
1347 preferred_stack_boundary)
1348 int reg_parm_stack_space;
1349 struct args_size *args_size;
1350 int preferred_stack_boundary ATTRIBUTE_UNUSED;
1352 int unadjusted_args_size = args_size->constant;
1354 /* For accumulate outgoing args mode we don't need to align, since the frame
1355 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1356 backends from generating missaligned frame sizes. */
1357 #ifdef STACK_BOUNDARY
1358 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1359 preferred_stack_boundary = STACK_BOUNDARY;
1362 /* Compute the actual size of the argument block required. The variable
1363 and constant sizes must be combined, the size may have to be rounded,
1364 and there may be a minimum required size. */
1368 args_size->var = ARGS_SIZE_TREE (*args_size);
1369 args_size->constant = 0;
1371 #ifdef PREFERRED_STACK_BOUNDARY
1372 preferred_stack_boundary /= BITS_PER_UNIT;
1373 if (preferred_stack_boundary > 1)
1375 /* We don't handle this case yet. To handle it correctly we have
1376 to add the delta, round and substract the delta.
1377 Currently no machine description requires this support. */
1378 if (stack_pointer_delta & (preferred_stack_boundary - 1))
1380 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1384 if (reg_parm_stack_space > 0)
1387 = size_binop (MAX_EXPR, args_size->var,
1388 ssize_int (reg_parm_stack_space));
1390 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1391 /* The area corresponding to register parameters is not to count in
1392 the size of the block we need. So make the adjustment. */
1394 = size_binop (MINUS_EXPR, args_size->var,
1395 ssize_int (reg_parm_stack_space));
1401 #ifdef PREFERRED_STACK_BOUNDARY
1402 preferred_stack_boundary /= BITS_PER_UNIT;
1403 if (preferred_stack_boundary < 1)
1404 preferred_stack_boundary = 1;
1405 args_size->constant = (((args_size->constant
1406 + stack_pointer_delta
1407 + preferred_stack_boundary - 1)
1408 / preferred_stack_boundary
1409 * preferred_stack_boundary)
1410 - stack_pointer_delta);
1413 args_size->constant = MAX (args_size->constant,
1414 reg_parm_stack_space);
1416 #ifdef MAYBE_REG_PARM_STACK_SPACE
1417 if (reg_parm_stack_space == 0)
1418 args_size->constant = 0;
1421 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1422 args_size->constant -= reg_parm_stack_space;
1425 return unadjusted_args_size;
1428 /* Precompute parameters as needed for a function call.
1430 FLAGS is mask of ECF_* constants.
1432 NUM_ACTUALS is the number of arguments.
1434 ARGS is an array containing information for each argument; this
1435 routine fills in the INITIAL_VALUE and VALUE fields for each
1436 precomputed argument. */
1439 precompute_arguments (flags, num_actuals, args)
1442 struct arg_data *args;
1446 /* If this function call is cse'able, precompute all the parameters.
1447 Note that if the parameter is constructed into a temporary, this will
1448 cause an additional copy because the parameter will be constructed
1449 into a temporary location and then copied into the outgoing arguments.
1450 If a parameter contains a call to alloca and this function uses the
1451 stack, precompute the parameter. */
1453 /* If we preallocated the stack space, and some arguments must be passed
1454 on the stack, then we must precompute any parameter which contains a
1455 function call which will store arguments on the stack.
1456 Otherwise, evaluating the parameter may clobber previous parameters
1457 which have already been stored into the stack. (we have code to avoid
1458 such case by saving the ougoing stack arguments, but it results in
1461 for (i = 0; i < num_actuals; i++)
1462 if ((flags & (ECF_CONST | ECF_PURE))
1463 || calls_function (args[i].tree_value, !ACCUMULATE_OUTGOING_ARGS))
1465 /* If this is an addressable type, we cannot pre-evaluate it. */
1466 if (TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value)))
1472 = expand_expr (args[i].tree_value, NULL_RTX, VOIDmode, 0);
1474 preserve_temp_slots (args[i].value);
1477 /* ANSI doesn't require a sequence point here,
1478 but PCC has one, so this will avoid some problems. */
1481 args[i].initial_value = args[i].value
1482 = protect_from_queue (args[i].value, 0);
1484 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) != args[i].mode)
1487 = convert_modes (args[i].mode,
1488 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
1489 args[i].value, args[i].unsignedp);
1490 #ifdef PROMOTE_FOR_CALL_ONLY
1491 /* CSE will replace this only if it contains args[i].value
1492 pseudo, so convert it down to the declared mode using
1494 if (GET_CODE (args[i].value) == REG
1495 && GET_MODE_CLASS (args[i].mode) == MODE_INT)
1497 args[i].initial_value
1498 = gen_rtx_SUBREG (TYPE_MODE (TREE_TYPE (args[i].tree_value)),
1500 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
1501 SUBREG_PROMOTED_UNSIGNED_P (args[i].initial_value)
1502 = args[i].unsignedp;
1509 /* Given the current state of MUST_PREALLOCATE and information about
1510 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1511 compute and return the final value for MUST_PREALLOCATE. */
1514 finalize_must_preallocate (must_preallocate, num_actuals, args, args_size)
1515 int must_preallocate;
1517 struct arg_data *args;
1518 struct args_size *args_size;
1520 /* See if we have or want to preallocate stack space.
1522 If we would have to push a partially-in-regs parm
1523 before other stack parms, preallocate stack space instead.
1525 If the size of some parm is not a multiple of the required stack
1526 alignment, we must preallocate.
1528 If the total size of arguments that would otherwise create a copy in
1529 a temporary (such as a CALL) is more than half the total argument list
1530 size, preallocation is faster.
1532 Another reason to preallocate is if we have a machine (like the m88k)
1533 where stack alignment is required to be maintained between every
1534 pair of insns, not just when the call is made. However, we assume here
1535 that such machines either do not have push insns (and hence preallocation
1536 would occur anyway) or the problem is taken care of with
1539 if (! must_preallocate)
1541 int partial_seen = 0;
1542 int copy_to_evaluate_size = 0;
1545 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1547 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1549 else if (partial_seen && args[i].reg == 0)
1550 must_preallocate = 1;
1552 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1553 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1554 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1555 || TREE_CODE (args[i].tree_value) == COND_EXPR
1556 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1557 copy_to_evaluate_size
1558 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1561 if (copy_to_evaluate_size * 2 >= args_size->constant
1562 && args_size->constant > 0)
1563 must_preallocate = 1;
1565 return must_preallocate;
1568 /* If we preallocated stack space, compute the address of each argument
1569 and store it into the ARGS array.
1571 We need not ensure it is a valid memory address here; it will be
1572 validized when it is used.
1574 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1577 compute_argument_addresses (args, argblock, num_actuals)
1578 struct arg_data *args;
1584 rtx arg_reg = argblock;
1585 int i, arg_offset = 0;
1587 if (GET_CODE (argblock) == PLUS)
1588 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1590 for (i = 0; i < num_actuals; i++)
1592 rtx offset = ARGS_SIZE_RTX (args[i].offset);
1593 rtx slot_offset = ARGS_SIZE_RTX (args[i].slot_offset);
1596 /* Skip this parm if it will not be passed on the stack. */
1597 if (! args[i].pass_on_stack && args[i].reg != 0)
1600 if (GET_CODE (offset) == CONST_INT)
1601 addr = plus_constant (arg_reg, INTVAL (offset));
1603 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1605 addr = plus_constant (addr, arg_offset);
1606 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1607 set_mem_attributes (args[i].stack,
1608 TREE_TYPE (args[i].tree_value), 1);
1610 if (GET_CODE (slot_offset) == CONST_INT)
1611 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1613 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1615 addr = plus_constant (addr, arg_offset);
1616 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1617 set_mem_attributes (args[i].stack_slot,
1618 TREE_TYPE (args[i].tree_value), 1);
1620 /* Function incoming arguments may overlap with sibling call
1621 outgoing arguments and we cannot allow reordering of reads
1622 from function arguments with stores to outgoing arguments
1623 of sibling calls. */
1624 MEM_ALIAS_SET (args[i].stack) = 0;
1625 MEM_ALIAS_SET (args[i].stack_slot) = 0;
1630 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1631 in a call instruction.
1633 FNDECL is the tree node for the target function. For an indirect call
1634 FNDECL will be NULL_TREE.
1636 EXP is the CALL_EXPR for this call. */
1639 rtx_for_function_call (fndecl, exp)
1645 /* Get the function to call, in the form of RTL. */
1648 /* If this is the first use of the function, see if we need to
1649 make an external definition for it. */
1650 if (! TREE_USED (fndecl))
1652 assemble_external (fndecl);
1653 TREE_USED (fndecl) = 1;
1656 /* Get a SYMBOL_REF rtx for the function address. */
1657 funexp = XEXP (DECL_RTL (fndecl), 0);
1660 /* Generate an rtx (probably a pseudo-register) for the address. */
1665 expand_expr (TREE_OPERAND (exp, 0), NULL_RTX, VOIDmode, 0);
1666 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1668 /* Check the function is executable. */
1669 if (current_function_check_memory_usage)
1671 #ifdef POINTERS_EXTEND_UNSIGNED
1672 /* It might be OK to convert funexp in place, but there's
1673 a lot going on between here and when it happens naturally
1674 that this seems safer. */
1675 funaddr = convert_memory_address (Pmode, funexp);
1677 emit_library_call (chkr_check_exec_libfunc, LCT_CONST_MAKE_BLOCK,
1678 VOIDmode, 1, funaddr, Pmode);
1685 /* Do the register loads required for any wholly-register parms or any
1686 parms which are passed both on the stack and in a register. Their
1687 expressions were already evaluated.
1689 Mark all register-parms as living through the call, putting these USE
1690 insns in the CALL_INSN_FUNCTION_USAGE field. */
1693 load_register_parameters (args, num_actuals, call_fusage, flags)
1694 struct arg_data *args;
1701 #ifdef LOAD_ARGS_REVERSED
1702 for (i = num_actuals - 1; i >= 0; i--)
1704 for (i = 0; i < num_actuals; i++)
1707 rtx reg = ((flags & ECF_SIBCALL)
1708 ? args[i].tail_call_reg : args[i].reg);
1709 int partial = args[i].partial;
1714 /* Set to non-negative if must move a word at a time, even if just
1715 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1716 we just use a normal move insn. This value can be zero if the
1717 argument is a zero size structure with no fields. */
1718 nregs = (partial ? partial
1719 : (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1720 ? ((int_size_in_bytes (TREE_TYPE (args[i].tree_value))
1721 + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)
1724 /* Handle calls that pass values in multiple non-contiguous
1725 locations. The Irix 6 ABI has examples of this. */
1727 if (GET_CODE (reg) == PARALLEL)
1728 emit_group_load (reg, args[i].value,
1729 int_size_in_bytes (TREE_TYPE (args[i].tree_value)),
1730 TYPE_ALIGN (TREE_TYPE (args[i].tree_value)));
1732 /* If simple case, just do move. If normal partial, store_one_arg
1733 has already loaded the register for us. In all other cases,
1734 load the register(s) from memory. */
1736 else if (nregs == -1)
1737 emit_move_insn (reg, args[i].value);
1739 /* If we have pre-computed the values to put in the registers in
1740 the case of non-aligned structures, copy them in now. */
1742 else if (args[i].n_aligned_regs != 0)
1743 for (j = 0; j < args[i].n_aligned_regs; j++)
1744 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
1745 args[i].aligned_regs[j]);
1747 else if (partial == 0 || args[i].pass_on_stack)
1748 move_block_to_reg (REGNO (reg),
1749 validize_mem (args[i].value), nregs,
1752 /* Handle calls that pass values in multiple non-contiguous
1753 locations. The Irix 6 ABI has examples of this. */
1754 if (GET_CODE (reg) == PARALLEL)
1755 use_group_regs (call_fusage, reg);
1756 else if (nregs == -1)
1757 use_reg (call_fusage, reg);
1759 use_regs (call_fusage, REGNO (reg), nregs == 0 ? 1 : nregs);
1764 /* Try to integrate function. See expand_inline_function for documentation
1765 about the parameters. */
1768 try_to_integrate (fndecl, actparms, target, ignore, type, structure_value_addr)
1774 rtx structure_value_addr;
1779 rtx old_stack_level = 0;
1780 int reg_parm_stack_space = 0;
1782 #ifdef REG_PARM_STACK_SPACE
1783 #ifdef MAYBE_REG_PARM_STACK_SPACE
1784 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
1786 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
1790 before_call = get_last_insn ();
1792 timevar_push (TV_INTEGRATION);
1794 temp = expand_inline_function (fndecl, actparms, target,
1796 structure_value_addr);
1798 timevar_pop (TV_INTEGRATION);
1800 /* If inlining succeeded, return. */
1801 if (temp != (rtx) (HOST_WIDE_INT) - 1)
1803 if (ACCUMULATE_OUTGOING_ARGS)
1805 /* If the outgoing argument list must be preserved, push
1806 the stack before executing the inlined function if it
1809 for (i = reg_parm_stack_space - 1; i >= 0; i--)
1810 if (i < highest_outgoing_arg_in_use && stack_usage_map[i] != 0)
1813 if (stack_arg_under_construction || i >= 0)
1816 = before_call ? NEXT_INSN (before_call) : get_insns ();
1817 rtx insn = NULL_RTX, seq;
1819 /* Look for a call in the inline function code.
1820 If DECL_SAVED_INSNS (fndecl)->outgoing_args_size is
1821 nonzero then there is a call and it is not necessary
1822 to scan the insns. */
1824 if (DECL_SAVED_INSNS (fndecl)->outgoing_args_size == 0)
1825 for (insn = first_insn; insn; insn = NEXT_INSN (insn))
1826 if (GET_CODE (insn) == CALL_INSN)
1831 /* Reserve enough stack space so that the largest
1832 argument list of any function call in the inline
1833 function does not overlap the argument list being
1834 evaluated. This is usually an overestimate because
1835 allocate_dynamic_stack_space reserves space for an
1836 outgoing argument list in addition to the requested
1837 space, but there is no way to ask for stack space such
1838 that an argument list of a certain length can be
1841 Add the stack space reserved for register arguments, if
1842 any, in the inline function. What is really needed is the
1843 largest value of reg_parm_stack_space in the inline
1844 function, but that is not available. Using the current
1845 value of reg_parm_stack_space is wrong, but gives
1846 correct results on all supported machines. */
1848 int adjust = (DECL_SAVED_INSNS (fndecl)->outgoing_args_size
1849 + reg_parm_stack_space);
1852 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1853 allocate_dynamic_stack_space (GEN_INT (adjust),
1854 NULL_RTX, BITS_PER_UNIT);
1857 emit_insns_before (seq, first_insn);
1858 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
1863 /* If the result is equivalent to TARGET, return TARGET to simplify
1864 checks in store_expr. They can be equivalent but not equal in the
1865 case of a function that returns BLKmode. */
1866 if (temp != target && rtx_equal_p (temp, target))
1871 /* If inlining failed, mark FNDECL as needing to be compiled
1872 separately after all. If function was declared inline,
1874 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
1875 && optimize > 0 && !TREE_ADDRESSABLE (fndecl))
1877 warning_with_decl (fndecl, "inlining failed in call to `%s'");
1878 warning ("called from here");
1880 mark_addressable (fndecl);
1881 return (rtx) (HOST_WIDE_INT) - 1;
1884 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1885 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1886 bytes, then we would need to push some additional bytes to pad the
1887 arguments. So, we compute an adjust to the stack pointer for an
1888 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1889 bytes. Then, when the arguments are pushed the stack will be perfectly
1890 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1891 be popped after the call. Returns the adjustment. */
1894 combine_pending_stack_adjustment_and_call (unadjusted_args_size,
1896 preferred_unit_stack_boundary)
1897 int unadjusted_args_size;
1898 struct args_size *args_size;
1899 int preferred_unit_stack_boundary;
1901 /* The number of bytes to pop so that the stack will be
1902 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1903 HOST_WIDE_INT adjustment;
1904 /* The alignment of the stack after the arguments are pushed, if we
1905 just pushed the arguments without adjust the stack here. */
1906 HOST_WIDE_INT unadjusted_alignment;
1908 unadjusted_alignment
1909 = ((stack_pointer_delta + unadjusted_args_size)
1910 % preferred_unit_stack_boundary);
1912 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1913 as possible -- leaving just enough left to cancel out the
1914 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1915 PENDING_STACK_ADJUST is non-negative, and congruent to
1916 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1918 /* Begin by trying to pop all the bytes. */
1919 unadjusted_alignment
1920 = (unadjusted_alignment
1921 - (pending_stack_adjust % preferred_unit_stack_boundary));
1922 adjustment = pending_stack_adjust;
1923 /* Push enough additional bytes that the stack will be aligned
1924 after the arguments are pushed. */
1925 if (preferred_unit_stack_boundary > 1)
1927 if (unadjusted_alignment > 0)
1928 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
1930 adjustment += unadjusted_alignment;
1933 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1934 bytes after the call. The right number is the entire
1935 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1936 by the arguments in the first place. */
1938 = pending_stack_adjust - adjustment + unadjusted_args_size;
1943 /* Scan X expression if it does not dereference any argument slots
1944 we already clobbered by tail call arguments (as noted in stored_args_map
1946 Return non-zero if X expression dereferences such argument slots,
1950 check_sibcall_argument_overlap_1 (x)
1961 code = GET_CODE (x);
1965 if (XEXP (x, 0) == current_function_internal_arg_pointer)
1967 else if (GET_CODE (XEXP (x, 0)) == PLUS
1968 && XEXP (XEXP (x, 0), 0) ==
1969 current_function_internal_arg_pointer
1970 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT)
1971 i = INTVAL (XEXP (XEXP (x, 0), 1));
1975 #ifdef ARGS_GROW_DOWNWARD
1976 i = -i - GET_MODE_SIZE (GET_MODE (x));
1979 for (k = 0; k < GET_MODE_SIZE (GET_MODE (x)); k++)
1980 if (i + k < stored_args_map->n_bits
1981 && TEST_BIT (stored_args_map, i + k))
1987 /* Scan all subexpressions. */
1988 fmt = GET_RTX_FORMAT (code);
1989 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
1993 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
1996 else if (*fmt == 'E')
1998 for (j = 0; j < XVECLEN (x, i); j++)
1999 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
2006 /* Scan sequence after INSN if it does not dereference any argument slots
2007 we already clobbered by tail call arguments (as noted in stored_args_map
2008 bitmap). Add stack slots for ARG to stored_args_map bitmap afterwards.
2009 Return non-zero if sequence after INSN dereferences such argument slots,
2013 check_sibcall_argument_overlap (insn, arg)
2015 struct arg_data *arg;
2019 if (insn == NULL_RTX)
2020 insn = get_insns ();
2022 insn = NEXT_INSN (insn);
2024 for (; insn; insn = NEXT_INSN (insn))
2026 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
2029 #ifdef ARGS_GROW_DOWNWARD
2030 low = -arg->offset.constant - arg->size.constant;
2032 low = arg->offset.constant;
2035 for (high = low + arg->size.constant; low < high; low++)
2036 SET_BIT (stored_args_map, low);
2037 return insn != NULL_RTX;
2040 /* Generate all the code for a function call
2041 and return an rtx for its value.
2042 Store the value in TARGET (specified as an rtx) if convenient.
2043 If the value is stored in TARGET then TARGET is returned.
2044 If IGNORE is nonzero, then we ignore the value of the function call. */
2047 expand_call (exp, target, ignore)
2052 /* Nonzero if we are currently expanding a call. */
2053 static int currently_expanding_call = 0;
2055 /* List of actual parameters. */
2056 tree actparms = TREE_OPERAND (exp, 1);
2057 /* RTX for the function to be called. */
2059 /* Sequence of insns to perform a tail recursive "call". */
2060 rtx tail_recursion_insns = NULL_RTX;
2061 /* Sequence of insns to perform a normal "call". */
2062 rtx normal_call_insns = NULL_RTX;
2063 /* Sequence of insns to perform a tail recursive "call". */
2064 rtx tail_call_insns = NULL_RTX;
2065 /* Data type of the function. */
2067 /* Declaration of the function being called,
2068 or 0 if the function is computed (not known by name). */
2071 int try_tail_call = 1;
2072 int try_tail_recursion = 1;
2075 /* Register in which non-BLKmode value will be returned,
2076 or 0 if no value or if value is BLKmode. */
2078 /* Address where we should return a BLKmode value;
2079 0 if value not BLKmode. */
2080 rtx structure_value_addr = 0;
2081 /* Nonzero if that address is being passed by treating it as
2082 an extra, implicit first parameter. Otherwise,
2083 it is passed by being copied directly into struct_value_rtx. */
2084 int structure_value_addr_parm = 0;
2085 /* Size of aggregate value wanted, or zero if none wanted
2086 or if we are using the non-reentrant PCC calling convention
2087 or expecting the value in registers. */
2088 HOST_WIDE_INT struct_value_size = 0;
2089 /* Nonzero if called function returns an aggregate in memory PCC style,
2090 by returning the address of where to find it. */
2091 int pcc_struct_value = 0;
2093 /* Number of actual parameters in this call, including struct value addr. */
2095 /* Number of named args. Args after this are anonymous ones
2096 and they must all go on the stack. */
2099 /* Vector of information about each argument.
2100 Arguments are numbered in the order they will be pushed,
2101 not the order they are written. */
2102 struct arg_data *args;
2104 /* Total size in bytes of all the stack-parms scanned so far. */
2105 struct args_size args_size;
2106 struct args_size adjusted_args_size;
2107 /* Size of arguments before any adjustments (such as rounding). */
2108 int unadjusted_args_size;
2109 /* Data on reg parms scanned so far. */
2110 CUMULATIVE_ARGS args_so_far;
2111 /* Nonzero if a reg parm has been scanned. */
2113 /* Nonzero if this is an indirect function call. */
2115 /* Nonzero if we must avoid push-insns in the args for this call.
2116 If stack space is allocated for register parameters, but not by the
2117 caller, then it is preallocated in the fixed part of the stack frame.
2118 So the entire argument block must then be preallocated (i.e., we
2119 ignore PUSH_ROUNDING in that case). */
2121 int must_preallocate = !PUSH_ARGS;
2123 /* Size of the stack reserved for parameter registers. */
2124 int reg_parm_stack_space = 0;
2126 /* Address of space preallocated for stack parms
2127 (on machines that lack push insns), or 0 if space not preallocated. */
2130 /* Mask of ECF_ flags. */
2132 /* Nonzero if this is a call to an inline function. */
2133 int is_integrable = 0;
2134 #ifdef REG_PARM_STACK_SPACE
2135 /* Define the boundary of the register parm stack space that needs to be
2137 int low_to_save = -1, high_to_save;
2138 rtx save_area = 0; /* Place that it is saved */
2141 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
2142 char *initial_stack_usage_map = stack_usage_map;
2143 int old_stack_arg_under_construction = 0;
2145 rtx old_stack_level = 0;
2146 int old_pending_adj = 0;
2147 int old_inhibit_defer_pop = inhibit_defer_pop;
2148 int old_stack_allocated;
2150 register tree p = TREE_OPERAND (exp, 0);
2152 /* The alignment of the stack, in bits. */
2153 HOST_WIDE_INT preferred_stack_boundary;
2154 /* The alignment of the stack, in bytes. */
2155 HOST_WIDE_INT preferred_unit_stack_boundary;
2157 /* The value of the function call can be put in a hard register. But
2158 if -fcheck-memory-usage, code which invokes functions (and thus
2159 damages some hard registers) can be inserted before using the value.
2160 So, target is always a pseudo-register in that case. */
2161 if (current_function_check_memory_usage)
2164 /* See if this is "nothrow" function call. */
2165 if (TREE_NOTHROW (exp))
2166 flags |= ECF_NOTHROW;
2168 /* See if we can find a DECL-node for the actual function.
2169 As a result, decide whether this is a call to an integrable function. */
2171 fndecl = get_callee_fndecl (exp);
2175 && fndecl != current_function_decl
2176 && DECL_INLINE (fndecl)
2177 && DECL_SAVED_INSNS (fndecl)
2178 && DECL_SAVED_INSNS (fndecl)->inlinable)
2180 else if (! TREE_ADDRESSABLE (fndecl))
2182 /* In case this function later becomes inlinable,
2183 record that there was already a non-inline call to it.
2185 Use abstraction instead of setting TREE_ADDRESSABLE
2187 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
2190 warning_with_decl (fndecl, "can't inline call to `%s'");
2191 warning ("called from here");
2193 mark_addressable (fndecl);
2196 flags |= flags_from_decl_or_type (fndecl);
2199 /* If we don't have specific function to call, see if we have a
2200 attributes set in the type. */
2202 flags |= flags_from_decl_or_type (TREE_TYPE (TREE_TYPE (p)));
2204 /* Mark if the function returns with the stack pointer depressed. */
2205 if (TREE_CODE (TREE_TYPE (TREE_TYPE (p))) == FUNCTION_TYPE
2206 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (TREE_TYPE (p))))
2208 flags |= ECF_SP_DEPRESSED;
2209 flags &= ~(ECF_PURE | ECF_CONST);
2212 #ifdef REG_PARM_STACK_SPACE
2213 #ifdef MAYBE_REG_PARM_STACK_SPACE
2214 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
2216 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
2220 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2221 if (reg_parm_stack_space > 0 && PUSH_ARGS)
2222 must_preallocate = 1;
2225 /* Warn if this value is an aggregate type,
2226 regardless of which calling convention we are using for it. */
2227 if (warn_aggregate_return && AGGREGATE_TYPE_P (TREE_TYPE (exp)))
2228 warning ("function call has aggregate value");
2230 /* Set up a place to return a structure. */
2232 /* Cater to broken compilers. */
2233 if (aggregate_value_p (exp))
2235 /* This call returns a big structure. */
2236 flags &= ~(ECF_CONST | ECF_PURE);
2238 #ifdef PCC_STATIC_STRUCT_RETURN
2240 pcc_struct_value = 1;
2241 /* Easier than making that case work right. */
2244 /* In case this is a static function, note that it has been
2246 if (! TREE_ADDRESSABLE (fndecl))
2247 mark_addressable (fndecl);
2251 #else /* not PCC_STATIC_STRUCT_RETURN */
2253 struct_value_size = int_size_in_bytes (TREE_TYPE (exp));
2255 if (target && GET_CODE (target) == MEM)
2256 structure_value_addr = XEXP (target, 0);
2259 /* For variable-sized objects, we must be called with a target
2260 specified. If we were to allocate space on the stack here,
2261 we would have no way of knowing when to free it. */
2262 rtx d = assign_temp (TREE_TYPE (exp), 1, 1, 1);
2264 mark_temp_addr_taken (d);
2265 structure_value_addr = XEXP (d, 0);
2269 #endif /* not PCC_STATIC_STRUCT_RETURN */
2272 /* If called function is inline, try to integrate it. */
2276 rtx temp = try_to_integrate (fndecl, actparms, target,
2277 ignore, TREE_TYPE (exp),
2278 structure_value_addr);
2279 if (temp != (rtx) (HOST_WIDE_INT) - 1)
2283 /* Figure out the amount to which the stack should be aligned. */
2284 #ifdef PREFERRED_STACK_BOUNDARY
2285 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
2287 preferred_stack_boundary = STACK_BOUNDARY;
2290 /* Operand 0 is a pointer-to-function; get the type of the function. */
2291 funtype = TREE_TYPE (TREE_OPERAND (exp, 0));
2292 if (! POINTER_TYPE_P (funtype))
2294 funtype = TREE_TYPE (funtype);
2296 /* See if this is a call to a function that can return more than once
2297 or a call to longjmp or malloc. */
2298 flags |= special_function_p (fndecl, flags);
2300 if (flags & ECF_MAY_BE_ALLOCA)
2301 current_function_calls_alloca = 1;
2303 /* If struct_value_rtx is 0, it means pass the address
2304 as if it were an extra parameter. */
2305 if (structure_value_addr && struct_value_rtx == 0)
2307 /* If structure_value_addr is a REG other than
2308 virtual_outgoing_args_rtx, we can use always use it. If it
2309 is not a REG, we must always copy it into a register.
2310 If it is virtual_outgoing_args_rtx, we must copy it to another
2311 register in some cases. */
2312 rtx temp = (GET_CODE (structure_value_addr) != REG
2313 || (ACCUMULATE_OUTGOING_ARGS
2314 && stack_arg_under_construction
2315 && structure_value_addr == virtual_outgoing_args_rtx)
2316 ? copy_addr_to_reg (structure_value_addr)
2317 : structure_value_addr);
2320 = tree_cons (error_mark_node,
2321 make_tree (build_pointer_type (TREE_TYPE (funtype)),
2324 structure_value_addr_parm = 1;
2327 /* Count the arguments and set NUM_ACTUALS. */
2328 for (p = actparms, num_actuals = 0; p; p = TREE_CHAIN (p))
2331 /* Compute number of named args.
2332 Normally, don't include the last named arg if anonymous args follow.
2333 We do include the last named arg if STRICT_ARGUMENT_NAMING is nonzero.
2334 (If no anonymous args follow, the result of list_length is actually
2335 one too large. This is harmless.)
2337 If PRETEND_OUTGOING_VARARGS_NAMED is set and STRICT_ARGUMENT_NAMING is
2338 zero, this machine will be able to place unnamed args that were
2339 passed in registers into the stack. So treat all args as named.
2340 This allows the insns emitting for a specific argument list to be
2341 independent of the function declaration.
2343 If PRETEND_OUTGOING_VARARGS_NAMED is not set, we do not have any
2344 reliable way to pass unnamed args in registers, so we must force
2345 them into memory. */
2347 if ((STRICT_ARGUMENT_NAMING
2348 || ! PRETEND_OUTGOING_VARARGS_NAMED)
2349 && TYPE_ARG_TYPES (funtype) != 0)
2351 = (list_length (TYPE_ARG_TYPES (funtype))
2352 /* Don't include the last named arg. */
2353 - (STRICT_ARGUMENT_NAMING ? 0 : 1)
2354 /* Count the struct value address, if it is passed as a parm. */
2355 + structure_value_addr_parm);
2357 /* If we know nothing, treat all args as named. */
2358 n_named_args = num_actuals;
2360 /* Start updating where the next arg would go.
2362 On some machines (such as the PA) indirect calls have a different
2363 calling convention than normal calls. The last argument in
2364 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2366 INIT_CUMULATIVE_ARGS (args_so_far, funtype, NULL_RTX, (fndecl == 0));
2368 /* Make a vector to hold all the information about each arg. */
2369 args = (struct arg_data *) alloca (num_actuals * sizeof (struct arg_data));
2370 memset ((char *) args, 0, num_actuals * sizeof (struct arg_data));
2372 /* Build up entries inthe ARGS array, compute the size of the arguments
2373 into ARGS_SIZE, etc. */
2374 initialize_argument_information (num_actuals, args, &args_size,
2375 n_named_args, actparms, fndecl,
2376 &args_so_far, reg_parm_stack_space,
2377 &old_stack_level, &old_pending_adj,
2378 &must_preallocate, &flags);
2382 /* If this function requires a variable-sized argument list, don't
2383 try to make a cse'able block for this call. We may be able to
2384 do this eventually, but it is too complicated to keep track of
2385 what insns go in the cse'able block and which don't. */
2387 flags &= ~(ECF_CONST | ECF_PURE);
2388 must_preallocate = 1;
2391 /* Now make final decision about preallocating stack space. */
2392 must_preallocate = finalize_must_preallocate (must_preallocate,
2396 /* If the structure value address will reference the stack pointer, we
2397 must stabilize it. We don't need to do this if we know that we are
2398 not going to adjust the stack pointer in processing this call. */
2400 if (structure_value_addr
2401 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2402 || reg_mentioned_p (virtual_outgoing_args_rtx,
2403 structure_value_addr))
2405 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
2406 structure_value_addr = copy_to_reg (structure_value_addr);
2408 /* Tail calls can make things harder to debug, and we're traditionally
2409 pushed these optimizations into -O2. Don't try if we're already
2410 expanding a call, as that means we're an argument. Don't try if
2411 there's cleanups, as we know there's code to follow the call.
2413 If rtx_equal_function_value_matters is false, that means we've
2414 finished with regular parsing. Which means that some of the
2415 machinery we use to generate tail-calls is no longer in place.
2416 This is most often true of sjlj-exceptions, which we couldn't
2417 tail-call to anyway. */
2419 if (currently_expanding_call++ != 0
2420 || !flag_optimize_sibling_calls
2421 || !rtx_equal_function_value_matters
2422 || any_pending_cleanups (1)
2424 try_tail_call = try_tail_recursion = 0;
2426 /* Tail recursion fails, when we are not dealing with recursive calls. */
2427 if (!try_tail_recursion
2428 || TREE_CODE (TREE_OPERAND (exp, 0)) != ADDR_EXPR
2429 || TREE_OPERAND (TREE_OPERAND (exp, 0), 0) != current_function_decl)
2430 try_tail_recursion = 0;
2432 /* Rest of purposes for tail call optimizations to fail. */
2434 #ifdef HAVE_sibcall_epilogue
2435 !HAVE_sibcall_epilogue
2440 /* Doing sibling call optimization needs some work, since
2441 structure_value_addr can be allocated on the stack.
2442 It does not seem worth the effort since few optimizable
2443 sibling calls will return a structure. */
2444 || structure_value_addr != NULL_RTX
2445 /* If the register holding the address is a callee saved
2446 register, then we lose. We have no way to prevent that,
2447 so we only allow calls to named functions. */
2448 /* ??? This could be done by having the insn constraints
2449 use a register class that is all call-clobbered. Any
2450 reload insns generated to fix things up would appear
2451 before the sibcall_epilogue. */
2452 || fndecl == NULL_TREE
2453 || (flags & (ECF_RETURNS_TWICE | ECF_LONGJMP))
2454 || TREE_THIS_VOLATILE (fndecl)
2455 || !FUNCTION_OK_FOR_SIBCALL (fndecl)
2456 /* If this function requires more stack slots than the current
2457 function, we cannot change it into a sibling call. */
2458 || args_size.constant > current_function_args_size
2459 /* If the callee pops its own arguments, then it must pop exactly
2460 the same number of arguments as the current function. */
2461 || RETURN_POPS_ARGS (fndecl, funtype, args_size.constant)
2462 != RETURN_POPS_ARGS (current_function_decl,
2463 TREE_TYPE (current_function_decl),
2464 current_function_args_size))
2467 if (try_tail_call || try_tail_recursion)
2470 actparms = NULL_TREE;
2471 /* Ok, we're going to give the tail call the old college try.
2472 This means we're going to evaluate the function arguments
2473 up to three times. There are two degrees of badness we can
2474 encounter, those that can be unsaved and those that can't.
2475 (See unsafe_for_reeval commentary for details.)
2477 Generate a new argument list. Pass safe arguments through
2478 unchanged. For the easy badness wrap them in UNSAVE_EXPRs.
2479 For hard badness, evaluate them now and put their resulting
2480 rtx in a temporary VAR_DECL.
2482 initialize_argument_information has ordered the array for the
2483 order to be pushed, and we must remember this when reconstructing
2484 the original argument orde. */
2486 if (PUSH_ARGS_REVERSED)
2495 i = num_actuals - 1;
2499 for (; i != end; i += inc)
2501 switch (unsafe_for_reeval (args[i].tree_value))
2506 case 1: /* Mildly unsafe. */
2507 args[i].tree_value = unsave_expr (args[i].tree_value);
2510 case 2: /* Wildly unsafe. */
2512 tree var = build_decl (VAR_DECL, NULL_TREE,
2513 TREE_TYPE (args[i].tree_value));
2515 expand_expr (args[i].tree_value, NULL_RTX,
2516 VOIDmode, EXPAND_NORMAL));
2517 args[i].tree_value = var;
2524 /* We need to build actparms for optimize_tail_recursion. We can
2525 safely trash away TREE_PURPOSE, since it is unused by this
2527 if (try_tail_recursion)
2528 actparms = tree_cons (NULL_TREE, args[i].tree_value, actparms);
2530 /* Expanding one of those dangerous arguments could have added
2531 cleanups, but otherwise give it a whirl. */
2532 if (any_pending_cleanups (1))
2533 try_tail_call = try_tail_recursion = 0;
2536 /* Generate a tail recursion sequence when calling ourselves. */
2538 if (try_tail_recursion)
2540 /* We want to emit any pending stack adjustments before the tail
2541 recursion "call". That way we know any adjustment after the tail
2542 recursion call can be ignored if we indeed use the tail recursion
2544 int save_pending_stack_adjust = pending_stack_adjust;
2545 int save_stack_pointer_delta = stack_pointer_delta;
2547 /* Emit any queued insns now; otherwise they would end up in
2548 only one of the alternates. */
2551 /* Use a new sequence to hold any RTL we generate. We do not even
2552 know if we will use this RTL yet. The final decision can not be
2553 made until after RTL generation for the entire function is
2556 /* If expanding any of the arguments creates cleanups, we can't
2557 do a tailcall. So, we'll need to pop the pending cleanups
2558 list. If, however, all goes well, and there are no cleanups
2559 then the call to expand_start_target_temps will have no
2561 expand_start_target_temps ();
2562 if (optimize_tail_recursion (actparms, get_last_insn ()))
2564 if (any_pending_cleanups (1))
2565 try_tail_call = try_tail_recursion = 0;
2567 tail_recursion_insns = get_insns ();
2569 expand_end_target_temps ();
2572 /* Restore the original pending stack adjustment for the sibling and
2573 normal call cases below. */
2574 pending_stack_adjust = save_pending_stack_adjust;
2575 stack_pointer_delta = save_stack_pointer_delta;
2578 if (profile_arc_flag && (flags & ECF_FORK_OR_EXEC))
2580 /* A fork duplicates the profile information, and an exec discards
2581 it. We can't rely on fork/exec to be paired. So write out the
2582 profile information we have gathered so far, and clear it. */
2583 /* ??? When Linux's __clone is called with CLONE_VM set, profiling
2584 is subject to race conditions, just as with multithreaded
2587 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, "__bb_fork_func"), 0,
2591 /* Ensure current function's preferred stack boundary is at least
2592 what we need. We don't have to increase alignment for recursive
2594 if (cfun->preferred_stack_boundary < preferred_stack_boundary
2595 && fndecl != current_function_decl)
2596 cfun->preferred_stack_boundary = preferred_stack_boundary;
2598 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
2600 function_call_count++;
2602 /* We want to make two insn chains; one for a sibling call, the other
2603 for a normal call. We will select one of the two chains after
2604 initial RTL generation is complete. */
2605 for (pass = 0; pass < 2; pass++)
2607 int sibcall_failure = 0;
2608 /* We want to emit ay pending stack adjustments before the tail
2609 recursion "call". That way we know any adjustment after the tail
2610 recursion call can be ignored if we indeed use the tail recursion
2612 int save_pending_stack_adjust = 0;
2613 int save_stack_pointer_delta = 0;
2615 rtx before_call, next_arg_reg;
2619 if (! try_tail_call)
2622 /* Emit any queued insns now; otherwise they would end up in
2623 only one of the alternates. */
2626 /* State variables we need to save and restore between
2628 save_pending_stack_adjust = pending_stack_adjust;
2629 save_stack_pointer_delta = stack_pointer_delta;
2632 flags &= ~ECF_SIBCALL;
2634 flags |= ECF_SIBCALL;
2636 /* Other state variables that we must reinitialize each time
2637 through the loop (that are not initialized by the loop itself). */
2641 /* Start a new sequence for the normal call case.
2643 From this point on, if the sibling call fails, we want to set
2644 sibcall_failure instead of continuing the loop. */
2649 /* We know at this point that there are not currently any
2650 pending cleanups. If, however, in the process of evaluating
2651 the arguments we were to create some, we'll need to be
2652 able to get rid of them. */
2653 expand_start_target_temps ();
2656 /* Don't let pending stack adjusts add up to too much.
2657 Also, do all pending adjustments now if there is any chance
2658 this might be a call to alloca or if we are expanding a sibling
2660 if (pending_stack_adjust >= 32
2661 || (pending_stack_adjust > 0 && (flags & ECF_MAY_BE_ALLOCA))
2663 do_pending_stack_adjust ();
2665 /* When calling a const function, we must pop the stack args right away,
2666 so that the pop is deleted or moved with the call. */
2667 if (flags & (ECF_CONST | ECF_PURE))
2670 /* Push the temporary stack slot level so that we can free any
2671 temporaries we make. */
2674 #ifdef FINAL_REG_PARM_STACK_SPACE
2675 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
2678 /* Precompute any arguments as needed. */
2680 precompute_arguments (flags, num_actuals, args);
2682 /* Now we are about to start emitting insns that can be deleted
2683 if a libcall is deleted. */
2684 if (flags & (ECF_CONST | ECF_PURE | ECF_MALLOC))
2687 adjusted_args_size = args_size;
2688 /* Compute the actual size of the argument block required. The variable
2689 and constant sizes must be combined, the size may have to be rounded,
2690 and there may be a minimum required size. When generating a sibcall
2691 pattern, do not round up, since we'll be re-using whatever space our
2693 unadjusted_args_size
2694 = compute_argument_block_size (reg_parm_stack_space,
2695 &adjusted_args_size,
2697 : preferred_stack_boundary));
2699 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
2701 /* The argument block when performing a sibling call is the
2702 incoming argument block. */
2705 argblock = virtual_incoming_args_rtx;
2706 stored_args_map = sbitmap_alloc (args_size.constant);
2707 sbitmap_zero (stored_args_map);
2710 /* If we have no actual push instructions, or shouldn't use them,
2711 make space for all args right now. */
2712 else if (adjusted_args_size.var != 0)
2714 if (old_stack_level == 0)
2716 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
2717 old_pending_adj = pending_stack_adjust;
2718 pending_stack_adjust = 0;
2719 /* stack_arg_under_construction says whether a stack arg is
2720 being constructed at the old stack level. Pushing the stack
2721 gets a clean outgoing argument block. */
2722 old_stack_arg_under_construction = stack_arg_under_construction;
2723 stack_arg_under_construction = 0;
2725 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
2729 /* Note that we must go through the motions of allocating an argument
2730 block even if the size is zero because we may be storing args
2731 in the area reserved for register arguments, which may be part of
2734 int needed = adjusted_args_size.constant;
2736 /* Store the maximum argument space used. It will be pushed by
2737 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2740 if (needed > current_function_outgoing_args_size)
2741 current_function_outgoing_args_size = needed;
2743 if (must_preallocate)
2745 if (ACCUMULATE_OUTGOING_ARGS)
2747 /* Since the stack pointer will never be pushed, it is
2748 possible for the evaluation of a parm to clobber
2749 something we have already written to the stack.
2750 Since most function calls on RISC machines do not use
2751 the stack, this is uncommon, but must work correctly.
2753 Therefore, we save any area of the stack that was already
2754 written and that we are using. Here we set up to do this
2755 by making a new stack usage map from the old one. The
2756 actual save will be done by store_one_arg.
2758 Another approach might be to try to reorder the argument
2759 evaluations to avoid this conflicting stack usage. */
2761 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2762 /* Since we will be writing into the entire argument area,
2763 the map must be allocated for its entire size, not just
2764 the part that is the responsibility of the caller. */
2765 needed += reg_parm_stack_space;
2768 #ifdef ARGS_GROW_DOWNWARD
2769 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2772 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2776 = (char *) alloca (highest_outgoing_arg_in_use);
2778 if (initial_highest_arg_in_use)
2779 memcpy (stack_usage_map, initial_stack_usage_map,
2780 initial_highest_arg_in_use);
2782 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2783 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
2784 (highest_outgoing_arg_in_use
2785 - initial_highest_arg_in_use));
2788 /* The address of the outgoing argument list must not be
2789 copied to a register here, because argblock would be left
2790 pointing to the wrong place after the call to
2791 allocate_dynamic_stack_space below. */
2793 argblock = virtual_outgoing_args_rtx;
2797 if (inhibit_defer_pop == 0)
2799 /* Try to reuse some or all of the pending_stack_adjust
2800 to get this space. */
2802 = (combine_pending_stack_adjustment_and_call
2803 (unadjusted_args_size,
2804 &adjusted_args_size,
2805 preferred_unit_stack_boundary));
2807 /* combine_pending_stack_adjustment_and_call computes
2808 an adjustment before the arguments are allocated.
2809 Account for them and see whether or not the stack
2810 needs to go up or down. */
2811 needed = unadjusted_args_size - needed;
2815 /* We're releasing stack space. */
2816 /* ??? We can avoid any adjustment at all if we're
2817 already aligned. FIXME. */
2818 pending_stack_adjust = -needed;
2819 do_pending_stack_adjust ();
2823 /* We need to allocate space. We'll do that in
2824 push_block below. */
2825 pending_stack_adjust = 0;
2828 /* Special case this because overhead of `push_block' in
2829 this case is non-trivial. */
2831 argblock = virtual_outgoing_args_rtx;
2833 argblock = push_block (GEN_INT (needed), 0, 0);
2835 /* We only really need to call `copy_to_reg' in the case
2836 where push insns are going to be used to pass ARGBLOCK
2837 to a function call in ARGS. In that case, the stack
2838 pointer changes value from the allocation point to the
2839 call point, and hence the value of
2840 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2841 as well always do it. */
2842 argblock = copy_to_reg (argblock);
2844 /* The save/restore code in store_one_arg handles all
2845 cases except one: a constructor call (including a C
2846 function returning a BLKmode struct) to initialize
2848 if (stack_arg_under_construction)
2850 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2851 rtx push_size = GEN_INT (reg_parm_stack_space
2852 + adjusted_args_size.constant);
2854 rtx push_size = GEN_INT (adjusted_args_size.constant);
2856 if (old_stack_level == 0)
2858 emit_stack_save (SAVE_BLOCK, &old_stack_level,
2860 old_pending_adj = pending_stack_adjust;
2861 pending_stack_adjust = 0;
2862 /* stack_arg_under_construction says whether a stack
2863 arg is being constructed at the old stack level.
2864 Pushing the stack gets a clean outgoing argument
2866 old_stack_arg_under_construction
2867 = stack_arg_under_construction;
2868 stack_arg_under_construction = 0;
2869 /* Make a new map for the new argument list. */
2870 stack_usage_map = (char *)
2871 alloca (highest_outgoing_arg_in_use);
2872 memset (stack_usage_map, 0, highest_outgoing_arg_in_use);
2873 highest_outgoing_arg_in_use = 0;
2875 allocate_dynamic_stack_space (push_size, NULL_RTX,
2878 /* If argument evaluation might modify the stack pointer,
2879 copy the address of the argument list to a register. */
2880 for (i = 0; i < num_actuals; i++)
2881 if (args[i].pass_on_stack)
2883 argblock = copy_addr_to_reg (argblock);
2890 compute_argument_addresses (args, argblock, num_actuals);
2892 #ifdef PREFERRED_STACK_BOUNDARY
2893 /* If we push args individually in reverse order, perform stack alignment
2894 before the first push (the last arg). */
2895 if (PUSH_ARGS_REVERSED && argblock == 0
2896 && adjusted_args_size.constant != unadjusted_args_size)
2898 /* When the stack adjustment is pending, we get better code
2899 by combining the adjustments. */
2900 if (pending_stack_adjust
2901 && ! (flags & (ECF_CONST | ECF_PURE))
2902 && ! inhibit_defer_pop)
2904 pending_stack_adjust
2905 = (combine_pending_stack_adjustment_and_call
2906 (unadjusted_args_size,
2907 &adjusted_args_size,
2908 preferred_unit_stack_boundary));
2909 do_pending_stack_adjust ();
2911 else if (argblock == 0)
2912 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2913 - unadjusted_args_size));
2915 /* Now that the stack is properly aligned, pops can't safely
2916 be deferred during the evaluation of the arguments. */
2920 /* Don't try to defer pops if preallocating, not even from the first arg,
2921 since ARGBLOCK probably refers to the SP. */
2925 funexp = rtx_for_function_call (fndecl, exp);
2927 /* Figure out the register where the value, if any, will come back. */
2929 if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
2930 && ! structure_value_addr)
2932 if (pcc_struct_value)
2933 valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
2934 fndecl, (pass == 0));
2936 valreg = hard_function_value (TREE_TYPE (exp), fndecl, (pass == 0));
2939 /* Precompute all register parameters. It isn't safe to compute anything
2940 once we have started filling any specific hard regs. */
2941 precompute_register_parameters (num_actuals, args, ®_parm_seen);
2943 #ifdef REG_PARM_STACK_SPACE
2944 /* Save the fixed argument area if it's part of the caller's frame and
2945 is clobbered by argument setup for this call. */
2946 if (ACCUMULATE_OUTGOING_ARGS && pass)
2947 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
2948 &low_to_save, &high_to_save);
2951 /* Now store (and compute if necessary) all non-register parms.
2952 These come before register parms, since they can require block-moves,
2953 which could clobber the registers used for register parms.
2954 Parms which have partial registers are not stored here,
2955 but we do preallocate space here if they want that. */
2957 for (i = 0; i < num_actuals; i++)
2958 if (args[i].reg == 0 || args[i].pass_on_stack)
2960 rtx before_arg = get_last_insn ();
2962 if (store_one_arg (&args[i], argblock, flags,
2963 adjusted_args_size.var != 0,
2964 reg_parm_stack_space)
2966 && check_sibcall_argument_overlap (before_arg,
2968 sibcall_failure = 1;
2971 /* If we have a parm that is passed in registers but not in memory
2972 and whose alignment does not permit a direct copy into registers,
2973 make a group of pseudos that correspond to each register that we
2975 if (STRICT_ALIGNMENT)
2976 store_unaligned_arguments_into_pseudos (args, num_actuals);
2978 /* Now store any partially-in-registers parm.
2979 This is the last place a block-move can happen. */
2981 for (i = 0; i < num_actuals; i++)
2982 if (args[i].partial != 0 && ! args[i].pass_on_stack)
2984 rtx before_arg = get_last_insn ();
2986 if (store_one_arg (&args[i], argblock, flags,
2987 adjusted_args_size.var != 0,
2988 reg_parm_stack_space)
2990 && check_sibcall_argument_overlap (before_arg,
2992 sibcall_failure = 1;
2995 #ifdef PREFERRED_STACK_BOUNDARY
2996 /* If we pushed args in forward order, perform stack alignment
2997 after pushing the last arg. */
2998 if (!PUSH_ARGS_REVERSED && argblock == 0)
2999 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
3000 - unadjusted_args_size));
3003 /* If register arguments require space on the stack and stack space
3004 was not preallocated, allocate stack space here for arguments
3005 passed in registers. */
3006 #ifdef OUTGOING_REG_PARM_STACK_SPACE
3007 if (!ACCUMULATE_OUTGOING_ARGS
3008 && must_preallocate == 0 && reg_parm_stack_space > 0)
3009 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
3012 /* Pass the function the address in which to return a
3014 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
3016 emit_move_insn (struct_value_rtx,
3018 force_operand (structure_value_addr,
3021 /* Mark the memory for the aggregate as write-only. */
3022 if (current_function_check_memory_usage)
3023 emit_library_call (chkr_set_right_libfunc, LCT_CONST_MAKE_BLOCK,
3025 structure_value_addr, ptr_mode,
3026 GEN_INT (struct_value_size),
3027 TYPE_MODE (sizetype),
3028 GEN_INT (MEMORY_USE_WO),
3029 TYPE_MODE (integer_type_node));
3031 if (GET_CODE (struct_value_rtx) == REG)
3032 use_reg (&call_fusage, struct_value_rtx);
3035 funexp = prepare_call_address (funexp, fndecl, &call_fusage,
3038 load_register_parameters (args, num_actuals, &call_fusage, flags);
3040 /* Perform postincrements before actually calling the function. */
3043 /* Save a pointer to the last insn before the call, so that we can
3044 later safely search backwards to find the CALL_INSN. */
3045 before_call = get_last_insn ();
3047 /* Set up next argument register. For sibling calls on machines
3048 with register windows this should be the incoming register. */
3049 #ifdef FUNCTION_INCOMING_ARG
3051 next_arg_reg = FUNCTION_INCOMING_ARG (args_so_far, VOIDmode,
3055 next_arg_reg = FUNCTION_ARG (args_so_far, VOIDmode,
3058 /* All arguments and registers used for the call must be set up by
3061 #ifdef PREFERRED_STACK_BOUNDARY
3062 /* Stack must be properly aligned now. */
3063 if (pass && stack_pointer_delta % preferred_unit_stack_boundary)
3067 /* Generate the actual call instruction. */
3068 emit_call_1 (funexp, fndecl, funtype, unadjusted_args_size,
3069 adjusted_args_size.constant, struct_value_size,
3070 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
3073 /* Verify that we've deallocated all the stack we used. */
3075 && old_stack_allocated != stack_pointer_delta - pending_stack_adjust)
3078 /* If call is cse'able, make appropriate pair of reg-notes around it.
3079 Test valreg so we don't crash; may safely ignore `const'
3080 if return type is void. Disable for PARALLEL return values, because
3081 we have no way to move such values into a pseudo register. */
3083 && (flags & (ECF_CONST | ECF_PURE))
3084 && valreg != 0 && GET_CODE (valreg) != PARALLEL)
3087 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3090 /* Mark the return value as a pointer if needed. */
3091 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3092 mark_reg_pointer (temp, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp))));
3094 /* Construct an "equal form" for the value which mentions all the
3095 arguments in order as well as the function name. */
3096 for (i = 0; i < num_actuals; i++)
3097 note = gen_rtx_EXPR_LIST (VOIDmode, args[i].initial_value, note);
3098 note = gen_rtx_EXPR_LIST (VOIDmode, funexp, note);
3100 insns = get_insns ();
3103 if (flags & ECF_PURE)
3104 note = gen_rtx_EXPR_LIST (VOIDmode,
3105 gen_rtx_USE (VOIDmode,
3106 gen_rtx_MEM (BLKmode,
3107 gen_rtx_SCRATCH (VOIDmode))), note);
3109 emit_libcall_block (insns, temp, valreg, note);
3113 else if (flags & (ECF_CONST | ECF_PURE))
3115 /* Otherwise, just write out the sequence without a note. */
3116 rtx insns = get_insns ();
3121 else if (flags & ECF_MALLOC)
3123 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3126 /* The return value from a malloc-like function is a pointer. */
3127 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3128 mark_reg_pointer (temp, BIGGEST_ALIGNMENT);
3130 emit_move_insn (temp, valreg);
3132 /* The return value from a malloc-like function can not alias
3134 last = get_last_insn ();
3136 gen_rtx_EXPR_LIST (REG_NOALIAS, temp, REG_NOTES (last));
3138 /* Write out the sequence. */
3139 insns = get_insns ();
3145 /* For calls to `setjmp', etc., inform flow.c it should complain
3146 if nonvolatile values are live. For functions that cannot return,
3147 inform flow that control does not fall through. */
3149 if ((flags & (ECF_RETURNS_TWICE | ECF_NORETURN | ECF_LONGJMP)) || pass == 0)
3151 /* The barrier or NOTE_INSN_SETJMP note must be emitted
3152 immediately after the CALL_INSN. Some ports emit more
3153 than just a CALL_INSN above, so we must search for it here. */
3155 rtx last = get_last_insn ();
3156 while (GET_CODE (last) != CALL_INSN)
3158 last = PREV_INSN (last);
3159 /* There was no CALL_INSN? */
3160 if (last == before_call)
3164 if (flags & ECF_RETURNS_TWICE)
3166 emit_note_after (NOTE_INSN_SETJMP, last);
3167 current_function_calls_setjmp = 1;
3170 emit_barrier_after (last);
3173 if (flags & ECF_LONGJMP)
3174 current_function_calls_longjmp = 1;
3176 /* If this function is returning into a memory location marked as
3177 readonly, it means it is initializing that location. But we normally
3178 treat functions as not clobbering such locations, so we need to
3179 specify that this one does. */
3180 if (target != 0 && GET_CODE (target) == MEM
3181 && structure_value_addr != 0 && RTX_UNCHANGING_P (target))
3182 emit_insn (gen_rtx_CLOBBER (VOIDmode, target));
3184 /* If value type not void, return an rtx for the value. */
3186 /* If there are cleanups to be called, don't use a hard reg as target.
3187 We need to double check this and see if it matters anymore. */
3188 if (any_pending_cleanups (1))
3190 if (target && REG_P (target)
3191 && REGNO (target) < FIRST_PSEUDO_REGISTER)
3193 sibcall_failure = 1;
3196 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
3199 target = const0_rtx;
3201 else if (structure_value_addr)
3203 if (target == 0 || GET_CODE (target) != MEM)
3206 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3207 memory_address (TYPE_MODE (TREE_TYPE (exp)),
3208 structure_value_addr));
3209 set_mem_attributes (target, exp, 1);
3212 else if (pcc_struct_value)
3214 /* This is the special C++ case where we need to
3215 know what the true target was. We take care to
3216 never use this value more than once in one expression. */
3217 target = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3218 copy_to_reg (valreg));
3219 set_mem_attributes (target, exp, 1);
3221 /* Handle calls that return values in multiple non-contiguous locations.
3222 The Irix 6 ABI has examples of this. */
3223 else if (GET_CODE (valreg) == PARALLEL)
3227 /* This will only be assigned once, so it can be readonly. */
3228 tree nt = build_qualified_type (TREE_TYPE (exp),
3229 (TYPE_QUALS (TREE_TYPE (exp))
3230 | TYPE_QUAL_CONST));
3232 target = assign_temp (nt, 0, 1, 1);
3233 preserve_temp_slots (target);
3236 if (! rtx_equal_p (target, valreg))
3237 emit_group_store (target, valreg,
3238 int_size_in_bytes (TREE_TYPE (exp)),
3239 TYPE_ALIGN (TREE_TYPE (exp)));
3241 /* We can not support sibling calls for this case. */
3242 sibcall_failure = 1;
3245 && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
3246 && GET_MODE (target) == GET_MODE (valreg))
3248 /* TARGET and VALREG cannot be equal at this point because the
3249 latter would not have REG_FUNCTION_VALUE_P true, while the
3250 former would if it were referring to the same register.
3252 If they refer to the same register, this move will be a no-op,
3253 except when function inlining is being done. */
3254 emit_move_insn (target, valreg);
3256 else if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
3258 target = copy_blkmode_from_reg (target, valreg, TREE_TYPE (exp));
3260 /* We can not support sibling calls for this case. */
3261 sibcall_failure = 1;
3264 target = copy_to_reg (valreg);
3266 #ifdef PROMOTE_FUNCTION_RETURN
3267 /* If we promoted this return value, make the proper SUBREG. TARGET
3268 might be const0_rtx here, so be careful. */
3269 if (GET_CODE (target) == REG
3270 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
3271 && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
3273 tree type = TREE_TYPE (exp);
3274 int unsignedp = TREE_UNSIGNED (type);
3276 /* If we don't promote as expected, something is wrong. */
3277 if (GET_MODE (target)
3278 != promote_mode (type, TYPE_MODE (type), &unsignedp, 1))
3281 target = gen_rtx_SUBREG (TYPE_MODE (type), target, 0);
3282 SUBREG_PROMOTED_VAR_P (target) = 1;
3283 SUBREG_PROMOTED_UNSIGNED_P (target) = unsignedp;
3287 /* If size of args is variable or this was a constructor call for a stack
3288 argument, restore saved stack-pointer value. */
3290 if (old_stack_level && ! (flags & ECF_SP_DEPRESSED))
3292 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
3293 pending_stack_adjust = old_pending_adj;
3294 stack_arg_under_construction = old_stack_arg_under_construction;
3295 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3296 stack_usage_map = initial_stack_usage_map;
3297 sibcall_failure = 1;
3299 else if (ACCUMULATE_OUTGOING_ARGS && pass)
3301 #ifdef REG_PARM_STACK_SPACE
3304 restore_fixed_argument_area (save_area, argblock,
3305 high_to_save, low_to_save);
3309 /* If we saved any argument areas, restore them. */
3310 for (i = 0; i < num_actuals; i++)
3311 if (args[i].save_area)
3313 enum machine_mode save_mode = GET_MODE (args[i].save_area);
3315 = gen_rtx_MEM (save_mode,
3316 memory_address (save_mode,
3317 XEXP (args[i].stack_slot, 0)));
3319 if (save_mode != BLKmode)
3320 emit_move_insn (stack_area, args[i].save_area);
3322 emit_block_move (stack_area,
3323 validize_mem (args[i].save_area),
3324 GEN_INT (args[i].size.constant),
3328 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3329 stack_usage_map = initial_stack_usage_map;
3332 /* If this was alloca, record the new stack level for nonlocal gotos.
3333 Check for the handler slots since we might not have a save area
3334 for non-local gotos. */
3336 if ((flags & ECF_MAY_BE_ALLOCA) && nonlocal_goto_handler_slots != 0)
3337 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
3341 /* Free up storage we no longer need. */
3342 for (i = 0; i < num_actuals; ++i)
3343 if (args[i].aligned_regs)
3344 free (args[i].aligned_regs);
3348 /* Undo the fake expand_start_target_temps we did earlier. If
3349 there had been any cleanups created, we've already set
3351 expand_end_target_temps ();
3354 insns = get_insns ();
3359 tail_call_insns = insns;
3361 /* Restore the pending stack adjustment now that we have
3362 finished generating the sibling call sequence. */
3364 pending_stack_adjust = save_pending_stack_adjust;
3365 stack_pointer_delta = save_stack_pointer_delta;
3367 /* Prepare arg structure for next iteration. */
3368 for (i = 0; i < num_actuals; i++)
3371 args[i].aligned_regs = 0;
3375 sbitmap_free (stored_args_map);
3378 normal_call_insns = insns;
3380 /* If something prevents making this a sibling call,
3381 zero out the sequence. */
3382 if (sibcall_failure)
3383 tail_call_insns = NULL_RTX;
3386 /* The function optimize_sibling_and_tail_recursive_calls doesn't
3387 handle CALL_PLACEHOLDERs inside other CALL_PLACEHOLDERs. This
3388 can happen if the arguments to this function call an inline
3389 function who's expansion contains another CALL_PLACEHOLDER.
3391 If there are any C_Ps in any of these sequences, replace them
3392 with their normal call. */
3394 for (insn = normal_call_insns; insn; insn = NEXT_INSN (insn))
3395 if (GET_CODE (insn) == CALL_INSN
3396 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3397 replace_call_placeholder (insn, sibcall_use_normal);
3399 for (insn = tail_call_insns; insn; insn = NEXT_INSN (insn))
3400 if (GET_CODE (insn) == CALL_INSN
3401 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3402 replace_call_placeholder (insn, sibcall_use_normal);
3404 for (insn = tail_recursion_insns; insn; insn = NEXT_INSN (insn))
3405 if (GET_CODE (insn) == CALL_INSN
3406 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3407 replace_call_placeholder (insn, sibcall_use_normal);
3409 /* If this was a potential tail recursion site, then emit a
3410 CALL_PLACEHOLDER with the normal and the tail recursion streams.
3411 One of them will be selected later. */
3412 if (tail_recursion_insns || tail_call_insns)
3414 /* The tail recursion label must be kept around. We could expose
3415 its use in the CALL_PLACEHOLDER, but that creates unwanted edges
3416 and makes determining true tail recursion sites difficult.
3418 So we set LABEL_PRESERVE_P here, then clear it when we select
3419 one of the call sequences after rtl generation is complete. */
3420 if (tail_recursion_insns)
3421 LABEL_PRESERVE_P (tail_recursion_label) = 1;
3422 emit_call_insn (gen_rtx_CALL_PLACEHOLDER (VOIDmode, normal_call_insns,
3424 tail_recursion_insns,
3425 tail_recursion_label));
3428 emit_insns (normal_call_insns);
3430 currently_expanding_call--;
3432 /* If this function returns with the stack pointer depressed, ensure
3433 this block saves and restores the stack pointer, show it was
3434 changed, and adjust for any outgoing arg space. */
3435 if (flags & ECF_SP_DEPRESSED)
3437 clear_pending_stack_adjust ();
3438 emit_insn (gen_rtx (CLOBBER, VOIDmode, stack_pointer_rtx));
3439 emit_move_insn (virtual_stack_dynamic_rtx, stack_pointer_rtx);
3440 save_stack_pointer ();
3446 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3447 The RETVAL parameter specifies whether return value needs to be saved, other
3448 parameters are documented in the emit_library_call function bellow. */
3450 emit_library_call_value_1 (retval, orgfun, value, fn_type, outmode, nargs, p)
3454 enum libcall_type fn_type;
3455 enum machine_mode outmode;
3459 /* Total size in bytes of all the stack-parms scanned so far. */
3460 struct args_size args_size;
3461 /* Size of arguments before any adjustments (such as rounding). */
3462 struct args_size original_args_size;
3463 register int argnum;
3467 struct args_size alignment_pad;
3469 CUMULATIVE_ARGS args_so_far;
3473 enum machine_mode mode;
3476 struct args_size offset;
3477 struct args_size size;
3481 int old_inhibit_defer_pop = inhibit_defer_pop;
3482 rtx call_fusage = 0;
3485 int pcc_struct_value = 0;
3486 int struct_value_size = 0;
3488 int reg_parm_stack_space = 0;
3492 #ifdef REG_PARM_STACK_SPACE
3493 /* Define the boundary of the register parm stack space that needs to be
3495 int low_to_save = -1, high_to_save = 0;
3496 rtx save_area = 0; /* Place that it is saved. */
3499 /* Size of the stack reserved for parameter registers. */
3500 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3501 char *initial_stack_usage_map = stack_usage_map;
3503 #ifdef REG_PARM_STACK_SPACE
3504 #ifdef MAYBE_REG_PARM_STACK_SPACE
3505 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
3507 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3511 /* No library functions can throw. */
3512 flags = ECF_NOTHROW;
3514 if (fn_type == LCT_CONST_MAKE_BLOCK)
3516 else if (fn_type == LCT_PURE_MAKE_BLOCK)
3518 else if (fn_type == LCT_NORETURN)
3519 flags |= ECF_NORETURN;
3522 #ifdef PREFERRED_STACK_BOUNDARY
3523 /* Ensure current function's preferred stack boundary is at least
3525 if (cfun->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3526 cfun->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3529 /* If this kind of value comes back in memory,
3530 decide where in memory it should come back. */
3531 if (outmode != VOIDmode && aggregate_value_p (type_for_mode (outmode, 0)))
3533 #ifdef PCC_STATIC_STRUCT_RETURN
3535 = hard_function_value (build_pointer_type (type_for_mode (outmode, 0)),
3537 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3538 pcc_struct_value = 1;
3540 value = gen_reg_rtx (outmode);
3541 #else /* not PCC_STATIC_STRUCT_RETURN */
3542 struct_value_size = GET_MODE_SIZE (outmode);
3543 if (value != 0 && GET_CODE (value) == MEM)
3546 mem_value = assign_temp (type_for_mode (outmode, 0), 0, 1, 1);
3549 /* This call returns a big structure. */
3550 flags &= ~(ECF_CONST | ECF_PURE);
3553 /* ??? Unfinished: must pass the memory address as an argument. */
3555 /* Copy all the libcall-arguments out of the varargs data
3556 and into a vector ARGVEC.
3558 Compute how to pass each argument. We only support a very small subset
3559 of the full argument passing conventions to limit complexity here since
3560 library functions shouldn't have many args. */
3562 argvec = (struct arg *) alloca ((nargs + 1) * sizeof (struct arg));
3563 memset ((char *) argvec, 0, (nargs + 1) * sizeof (struct arg));
3565 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3566 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far, outmode, fun);
3568 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun, 0);
3571 args_size.constant = 0;
3576 /* Now we are about to start emitting insns that can be deleted
3577 if a libcall is deleted. */
3578 if (flags & (ECF_CONST | ECF_PURE))
3583 /* If there's a structure value address to be passed,
3584 either pass it in the special place, or pass it as an extra argument. */
3585 if (mem_value && struct_value_rtx == 0 && ! pcc_struct_value)
3587 rtx addr = XEXP (mem_value, 0);
3590 /* Make sure it is a reasonable operand for a move or push insn. */
3591 if (GET_CODE (addr) != REG && GET_CODE (addr) != MEM
3592 && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
3593 addr = force_operand (addr, NULL_RTX);
3595 argvec[count].value = addr;
3596 argvec[count].mode = Pmode;
3597 argvec[count].partial = 0;
3599 argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
3600 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3601 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far, Pmode, NULL_TREE, 1))
3605 locate_and_pad_parm (Pmode, NULL_TREE,
3606 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3609 argvec[count].reg != 0,
3611 NULL_TREE, &args_size, &argvec[count].offset,
3612 &argvec[count].size, &alignment_pad);
3614 if (argvec[count].reg == 0 || argvec[count].partial != 0
3615 || reg_parm_stack_space > 0)
3616 args_size.constant += argvec[count].size.constant;
3618 FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree) 0, 1);
3623 for (; count < nargs; count++)
3625 rtx val = va_arg (p, rtx);
3626 enum machine_mode mode = va_arg (p, enum machine_mode);
3628 /* We cannot convert the arg value to the mode the library wants here;
3629 must do it earlier where we know the signedness of the arg. */
3631 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
3634 /* On some machines, there's no way to pass a float to a library fcn.
3635 Pass it as a double instead. */
3636 #ifdef LIBGCC_NEEDS_DOUBLE
3637 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
3638 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
3641 /* There's no need to call protect_from_queue, because
3642 either emit_move_insn or emit_push_insn will do that. */
3644 /* Make sure it is a reasonable operand for a move or push insn. */
3645 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
3646 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
3647 val = force_operand (val, NULL_RTX);
3649 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3650 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
3654 #ifdef FUNCTION_ARG_CALLEE_COPIES
3655 && ! FUNCTION_ARG_CALLEE_COPIES (args_so_far, mode,
3660 if (GET_MODE (val) == MEM && ! must_copy)
3664 slot = assign_temp (type_for_mode (mode, 0), 0, 1, 1);
3665 emit_move_insn (slot, val);
3669 tree type = type_for_mode (mode, 0);
3671 slot = gen_rtx_MEM (mode,
3672 expand_expr (build1 (ADDR_EXPR,
3675 make_tree (type, val)),
3676 NULL_RTX, VOIDmode, 0));
3679 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3680 gen_rtx_USE (VOIDmode, slot),
3683 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3684 gen_rtx_CLOBBER (VOIDmode,
3689 val = force_operand (XEXP (slot, 0), NULL_RTX);
3693 argvec[count].value = val;
3694 argvec[count].mode = mode;
3696 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
3698 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3699 argvec[count].partial
3700 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
3702 argvec[count].partial = 0;
3705 locate_and_pad_parm (mode, NULL_TREE,
3706 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3709 argvec[count].reg != 0,
3711 NULL_TREE, &args_size, &argvec[count].offset,
3712 &argvec[count].size, &alignment_pad);
3714 if (argvec[count].size.var)
3717 if (reg_parm_stack_space == 0 && argvec[count].partial)
3718 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
3720 if (argvec[count].reg == 0 || argvec[count].partial != 0
3721 || reg_parm_stack_space > 0)
3722 args_size.constant += argvec[count].size.constant;
3724 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree) 0, 1);
3727 #ifdef FINAL_REG_PARM_STACK_SPACE
3728 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
3731 /* If this machine requires an external definition for library
3732 functions, write one out. */
3733 assemble_external_libcall (fun);
3735 original_args_size = args_size;
3736 #ifdef PREFERRED_STACK_BOUNDARY
3737 args_size.constant = (((args_size.constant
3738 + stack_pointer_delta
3742 - stack_pointer_delta);
3745 args_size.constant = MAX (args_size.constant,
3746 reg_parm_stack_space);
3748 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3749 args_size.constant -= reg_parm_stack_space;
3752 if (args_size.constant > current_function_outgoing_args_size)
3753 current_function_outgoing_args_size = args_size.constant;
3755 if (ACCUMULATE_OUTGOING_ARGS)
3757 /* Since the stack pointer will never be pushed, it is possible for
3758 the evaluation of a parm to clobber something we have already
3759 written to the stack. Since most function calls on RISC machines
3760 do not use the stack, this is uncommon, but must work correctly.
3762 Therefore, we save any area of the stack that was already written
3763 and that we are using. Here we set up to do this by making a new
3764 stack usage map from the old one.
3766 Another approach might be to try to reorder the argument
3767 evaluations to avoid this conflicting stack usage. */
3769 needed = args_size.constant;
3771 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3772 /* Since we will be writing into the entire argument area, the
3773 map must be allocated for its entire size, not just the part that
3774 is the responsibility of the caller. */
3775 needed += reg_parm_stack_space;
3778 #ifdef ARGS_GROW_DOWNWARD
3779 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3782 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3785 stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
3787 if (initial_highest_arg_in_use)
3788 memcpy (stack_usage_map, initial_stack_usage_map,
3789 initial_highest_arg_in_use);
3791 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3792 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
3793 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
3796 /* The address of the outgoing argument list must not be copied to a
3797 register here, because argblock would be left pointing to the
3798 wrong place after the call to allocate_dynamic_stack_space below. */
3800 argblock = virtual_outgoing_args_rtx;
3805 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
3808 #ifdef PREFERRED_STACK_BOUNDARY
3809 /* If we push args individually in reverse order, perform stack alignment
3810 before the first push (the last arg). */
3811 if (argblock == 0 && PUSH_ARGS_REVERSED)
3812 anti_adjust_stack (GEN_INT (args_size.constant
3813 - original_args_size.constant));
3816 if (PUSH_ARGS_REVERSED)
3827 #ifdef REG_PARM_STACK_SPACE
3828 if (ACCUMULATE_OUTGOING_ARGS)
3830 /* The argument list is the property of the called routine and it
3831 may clobber it. If the fixed area has been used for previous
3832 parameters, we must save and restore it.
3834 Here we compute the boundary of the that needs to be saved, if any. */
3836 #ifdef ARGS_GROW_DOWNWARD
3837 for (count = 0; count < reg_parm_stack_space + 1; count++)
3839 for (count = 0; count < reg_parm_stack_space; count++)
3842 if (count >= highest_outgoing_arg_in_use
3843 || stack_usage_map[count] == 0)
3846 if (low_to_save == -1)
3847 low_to_save = count;
3849 high_to_save = count;
3852 if (low_to_save >= 0)
3854 int num_to_save = high_to_save - low_to_save + 1;
3855 enum machine_mode save_mode
3856 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
3859 /* If we don't have the required alignment, must do this in BLKmode. */
3860 if ((low_to_save & (MIN (GET_MODE_SIZE (save_mode),
3861 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
3862 save_mode = BLKmode;
3864 #ifdef ARGS_GROW_DOWNWARD
3865 stack_area = gen_rtx_MEM (save_mode,
3866 memory_address (save_mode,
3867 plus_constant (argblock,
3870 stack_area = gen_rtx_MEM (save_mode,
3871 memory_address (save_mode,
3872 plus_constant (argblock,
3875 if (save_mode == BLKmode)
3877 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
3878 emit_block_move (validize_mem (save_area), stack_area,
3879 GEN_INT (num_to_save), PARM_BOUNDARY);
3883 save_area = gen_reg_rtx (save_mode);
3884 emit_move_insn (save_area, stack_area);
3890 /* Push the args that need to be pushed. */
3892 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3893 are to be pushed. */
3894 for (count = 0; count < nargs; count++, argnum += inc)
3896 register enum machine_mode mode = argvec[argnum].mode;
3897 register rtx val = argvec[argnum].value;
3898 rtx reg = argvec[argnum].reg;
3899 int partial = argvec[argnum].partial;
3900 int lower_bound = 0, upper_bound = 0, i;
3902 if (! (reg != 0 && partial == 0))
3904 if (ACCUMULATE_OUTGOING_ARGS)
3906 /* If this is being stored into a pre-allocated, fixed-size,
3907 stack area, save any previous data at that location. */
3909 #ifdef ARGS_GROW_DOWNWARD
3910 /* stack_slot is negative, but we want to index stack_usage_map
3911 with positive values. */
3912 upper_bound = -argvec[argnum].offset.constant + 1;
3913 lower_bound = upper_bound - argvec[argnum].size.constant;
3915 lower_bound = argvec[argnum].offset.constant;
3916 upper_bound = lower_bound + argvec[argnum].size.constant;
3919 for (i = lower_bound; i < upper_bound; i++)
3920 if (stack_usage_map[i]
3921 /* Don't store things in the fixed argument area at this
3922 point; it has already been saved. */
3923 && i > reg_parm_stack_space)
3926 if (i != upper_bound)
3928 /* We need to make a save area. See what mode we can make
3930 enum machine_mode save_mode
3931 = mode_for_size (argvec[argnum].size.constant
3939 plus_constant (argblock,
3940 argvec[argnum].offset.constant)));
3941 argvec[argnum].save_area = gen_reg_rtx (save_mode);
3943 emit_move_insn (argvec[argnum].save_area, stack_area);
3947 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, 0, partial, reg, 0,
3948 argblock, GEN_INT (argvec[argnum].offset.constant),
3949 reg_parm_stack_space, ARGS_SIZE_RTX (alignment_pad));
3951 /* Now mark the segment we just used. */
3952 if (ACCUMULATE_OUTGOING_ARGS)
3953 for (i = lower_bound; i < upper_bound; i++)
3954 stack_usage_map[i] = 1;
3960 #ifdef PREFERRED_STACK_BOUNDARY
3961 /* If we pushed args in forward order, perform stack alignment
3962 after pushing the last arg. */
3963 if (argblock == 0 && !PUSH_ARGS_REVERSED)
3964 anti_adjust_stack (GEN_INT (args_size.constant
3965 - original_args_size.constant));
3968 if (PUSH_ARGS_REVERSED)
3973 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0);
3975 /* Now load any reg parms into their regs. */
3977 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3978 are to be pushed. */
3979 for (count = 0; count < nargs; count++, argnum += inc)
3981 register rtx val = argvec[argnum].value;
3982 rtx reg = argvec[argnum].reg;
3983 int partial = argvec[argnum].partial;
3985 /* Handle calls that pass values in multiple non-contiguous
3986 locations. The PA64 has examples of this for library calls. */
3987 if (reg != 0 && GET_CODE (reg) == PARALLEL)
3988 emit_group_load (reg, val,
3989 GET_MODE_SIZE (GET_MODE (val)),
3990 GET_MODE_ALIGNMENT (GET_MODE (val)));
3991 else if (reg != 0 && partial == 0)
3992 emit_move_insn (reg, val);
3997 /* Any regs containing parms remain in use through the call. */
3998 for (count = 0; count < nargs; count++)
4000 rtx reg = argvec[count].reg;
4001 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4002 use_group_regs (&call_fusage, reg);
4004 use_reg (&call_fusage, reg);
4007 /* Pass the function the address in which to return a structure value. */
4008 if (mem_value != 0 && struct_value_rtx != 0 && ! pcc_struct_value)
4010 emit_move_insn (struct_value_rtx,
4012 force_operand (XEXP (mem_value, 0),
4014 if (GET_CODE (struct_value_rtx) == REG)
4015 use_reg (&call_fusage, struct_value_rtx);
4018 /* Don't allow popping to be deferred, since then
4019 cse'ing of library calls could delete a call and leave the pop. */
4021 valreg = (mem_value == 0 && outmode != VOIDmode
4022 ? hard_libcall_value (outmode) : NULL_RTX);
4024 #ifdef PREFERRED_STACK_BOUNDARY
4025 /* Stack must be properly aligned now. */
4026 if (stack_pointer_delta & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1))
4030 before_call = get_last_insn ();
4032 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4033 will set inhibit_defer_pop to that value. */
4034 /* The return type is needed to decide how many bytes the function pops.
4035 Signedness plays no role in that, so for simplicity, we pretend it's
4036 always signed. We also assume that the list of arguments passed has
4037 no impact, so we pretend it is unknown. */
4040 get_identifier (XSTR (orgfun, 0)),
4041 build_function_type (outmode == VOIDmode ? void_type_node
4042 : type_for_mode (outmode, 0), NULL_TREE),
4043 original_args_size.constant, args_size.constant,
4045 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
4047 old_inhibit_defer_pop + 1, call_fusage, flags);
4049 /* For calls to `setjmp', etc., inform flow.c it should complain
4050 if nonvolatile values are live. For functions that cannot return,
4051 inform flow that control does not fall through. */
4053 if (flags & (ECF_RETURNS_TWICE | ECF_NORETURN | ECF_LONGJMP))
4055 /* The barrier or NOTE_INSN_SETJMP note must be emitted
4056 immediately after the CALL_INSN. Some ports emit more than
4057 just a CALL_INSN above, so we must search for it here. */
4059 rtx last = get_last_insn ();
4060 while (GET_CODE (last) != CALL_INSN)
4062 last = PREV_INSN (last);
4063 /* There was no CALL_INSN? */
4064 if (last == before_call)
4068 if (flags & ECF_RETURNS_TWICE)
4070 emit_note_after (NOTE_INSN_SETJMP, last);
4071 current_function_calls_setjmp = 1;
4074 emit_barrier_after (last);
4077 /* Now restore inhibit_defer_pop to its actual original value. */
4080 /* If call is cse'able, make appropriate pair of reg-notes around it.
4081 Test valreg so we don't crash; may safely ignore `const'
4082 if return type is void. Disable for PARALLEL return values, because
4083 we have no way to move such values into a pseudo register. */
4084 if ((flags & (ECF_CONST | ECF_PURE))
4085 && valreg != 0 && GET_CODE (valreg) != PARALLEL)
4088 rtx temp = gen_reg_rtx (GET_MODE (valreg));
4092 /* Construct an "equal form" for the value which mentions all the
4093 arguments in order as well as the function name. */
4094 for (i = 0; i < nargs; i++)
4095 note = gen_rtx_EXPR_LIST (VOIDmode, argvec[i].value, note);
4096 note = gen_rtx_EXPR_LIST (VOIDmode, fun, note);
4098 insns = get_insns ();
4101 if (flags & ECF_PURE)
4102 note = gen_rtx_EXPR_LIST (VOIDmode,
4103 gen_rtx_USE (VOIDmode,
4104 gen_rtx_MEM (BLKmode,
4105 gen_rtx_SCRATCH (VOIDmode))), note);
4107 emit_libcall_block (insns, temp, valreg, note);
4111 else if (flags & (ECF_CONST | ECF_PURE))
4113 /* Otherwise, just write out the sequence without a note. */
4114 rtx insns = get_insns ();
4121 /* Copy the value to the right place. */
4122 if (outmode != VOIDmode && retval)
4128 if (value != mem_value)
4129 emit_move_insn (value, mem_value);
4131 else if (value != 0)
4132 emit_move_insn (value, hard_libcall_value (outmode));
4134 value = hard_libcall_value (outmode);
4137 if (ACCUMULATE_OUTGOING_ARGS)
4139 #ifdef REG_PARM_STACK_SPACE
4142 enum machine_mode save_mode = GET_MODE (save_area);
4143 #ifdef ARGS_GROW_DOWNWARD
4145 = gen_rtx_MEM (save_mode,
4146 memory_address (save_mode,
4147 plus_constant (argblock,
4151 = gen_rtx_MEM (save_mode,
4152 memory_address (save_mode,
4153 plus_constant (argblock, low_to_save)));
4155 if (save_mode != BLKmode)
4156 emit_move_insn (stack_area, save_area);
4158 emit_block_move (stack_area, validize_mem (save_area),
4159 GEN_INT (high_to_save - low_to_save + 1),
4164 /* If we saved any argument areas, restore them. */
4165 for (count = 0; count < nargs; count++)
4166 if (argvec[count].save_area)
4168 enum machine_mode save_mode = GET_MODE (argvec[count].save_area);
4170 = gen_rtx_MEM (save_mode,
4173 plus_constant (argblock,
4174 argvec[count].offset.constant)));
4176 emit_move_insn (stack_area, argvec[count].save_area);
4179 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4180 stack_usage_map = initial_stack_usage_map;
4187 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4188 (emitting the queue unless NO_QUEUE is nonzero),
4189 for a value of mode OUTMODE,
4190 with NARGS different arguments, passed as alternating rtx values
4191 and machine_modes to convert them to.
4192 The rtx values should have been passed through protect_from_queue already.
4194 FN_TYPE will is zero for `normal' calls, one for `const' calls, wich
4195 which will be enclosed in REG_LIBCALL/REG_RETVAL notes and two for `pure'
4196 calls, that are handled like `const' calls with extra
4197 (use (memory (scratch)). */
4200 emit_library_call VPARAMS((rtx orgfun, enum libcall_type fn_type,
4201 enum machine_mode outmode, int nargs, ...))
4203 #ifndef ANSI_PROTOTYPES
4206 enum machine_mode outmode;
4211 VA_START (p, nargs);
4213 #ifndef ANSI_PROTOTYPES
4214 orgfun = va_arg (p, rtx);
4215 fn_type = va_arg (p, int);
4216 outmode = va_arg (p, enum machine_mode);
4217 nargs = va_arg (p, int);
4220 emit_library_call_value_1 (0, orgfun, NULL_RTX, fn_type, outmode, nargs, p);
4225 /* Like emit_library_call except that an extra argument, VALUE,
4226 comes second and says where to store the result.
4227 (If VALUE is zero, this function chooses a convenient way
4228 to return the value.
4230 This function returns an rtx for where the value is to be found.
4231 If VALUE is nonzero, VALUE is returned. */
4234 emit_library_call_value VPARAMS((rtx orgfun, rtx value,
4235 enum libcall_type fn_type,
4236 enum machine_mode outmode, int nargs, ...))
4238 #ifndef ANSI_PROTOTYPES
4242 enum machine_mode outmode;
4247 VA_START (p, nargs);
4249 #ifndef ANSI_PROTOTYPES
4250 orgfun = va_arg (p, rtx);
4251 value = va_arg (p, rtx);
4252 fn_type = va_arg (p, int);
4253 outmode = va_arg (p, enum machine_mode);
4254 nargs = va_arg (p, int);
4257 value = emit_library_call_value_1 (1, orgfun, value, fn_type, outmode, nargs, p);
4265 /* Return an rtx which represents a suitable home on the stack
4266 given TYPE, the type of the argument looking for a home.
4267 This is called only for BLKmode arguments.
4269 SIZE is the size needed for this target.
4270 ARGS_ADDR is the address of the bottom of the argument block for this call.
4271 OFFSET describes this parameter's offset into ARGS_ADDR. It is meaningless
4272 if this machine uses push insns. */
4275 target_for_arg (type, size, args_addr, offset)
4279 struct args_size offset;
4282 rtx offset_rtx = ARGS_SIZE_RTX (offset);
4284 /* We do not call memory_address if possible,
4285 because we want to address as close to the stack
4286 as possible. For non-variable sized arguments,
4287 this will be stack-pointer relative addressing. */
4288 if (GET_CODE (offset_rtx) == CONST_INT)
4289 target = plus_constant (args_addr, INTVAL (offset_rtx));
4292 /* I have no idea how to guarantee that this
4293 will work in the presence of register parameters. */
4294 target = gen_rtx_PLUS (Pmode, args_addr, offset_rtx);
4295 target = memory_address (QImode, target);
4298 return gen_rtx_MEM (BLKmode, target);
4302 /* Store a single argument for a function call
4303 into the register or memory area where it must be passed.
4304 *ARG describes the argument value and where to pass it.
4306 ARGBLOCK is the address of the stack-block for all the arguments,
4307 or 0 on a machine where arguments are pushed individually.
4309 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4310 so must be careful about how the stack is used.
4312 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4313 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4314 that we need not worry about saving and restoring the stack.
4316 FNDECL is the declaration of the function we are calling.
4318 Return non-zero if this arg should cause sibcall failure,
4322 store_one_arg (arg, argblock, flags, variable_size, reg_parm_stack_space)
4323 struct arg_data *arg;
4326 int variable_size ATTRIBUTE_UNUSED;
4327 int reg_parm_stack_space;
4329 register tree pval = arg->tree_value;
4333 int i, lower_bound = 0, upper_bound = 0;
4334 int sibcall_failure = 0;
4336 if (TREE_CODE (pval) == ERROR_MARK)
4339 /* Push a new temporary level for any temporaries we make for
4343 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
4345 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4346 save any previous data at that location. */
4347 if (argblock && ! variable_size && arg->stack)
4349 #ifdef ARGS_GROW_DOWNWARD
4350 /* stack_slot is negative, but we want to index stack_usage_map
4351 with positive values. */
4352 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4353 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
4357 lower_bound = upper_bound - arg->size.constant;
4359 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4360 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
4364 upper_bound = lower_bound + arg->size.constant;
4367 for (i = lower_bound; i < upper_bound; i++)
4368 if (stack_usage_map[i]
4369 /* Don't store things in the fixed argument area at this point;
4370 it has already been saved. */
4371 && i > reg_parm_stack_space)
4374 if (i != upper_bound)
4376 /* We need to make a save area. See what mode we can make it. */
4377 enum machine_mode save_mode
4378 = mode_for_size (arg->size.constant * BITS_PER_UNIT, MODE_INT, 1);
4380 = gen_rtx_MEM (save_mode,
4381 memory_address (save_mode,
4382 XEXP (arg->stack_slot, 0)));
4384 if (save_mode == BLKmode)
4386 tree ot = TREE_TYPE (arg->tree_value);
4387 tree nt = build_qualified_type (ot, (TYPE_QUALS (ot)
4388 | TYPE_QUAL_CONST));
4390 arg->save_area = assign_temp (nt, 0, 1, 1);
4391 preserve_temp_slots (arg->save_area);
4392 emit_block_move (validize_mem (arg->save_area), stack_area,
4393 expr_size (arg->tree_value),
4394 MIN (PARM_BOUNDARY, TYPE_ALIGN (nt)));
4398 arg->save_area = gen_reg_rtx (save_mode);
4399 emit_move_insn (arg->save_area, stack_area);
4403 /* Now that we have saved any slots that will be overwritten by this
4404 store, mark all slots this store will use. We must do this before
4405 we actually expand the argument since the expansion itself may
4406 trigger library calls which might need to use the same stack slot. */
4407 if (argblock && ! variable_size && arg->stack)
4408 for (i = lower_bound; i < upper_bound; i++)
4409 stack_usage_map[i] = 1;
4412 /* If this isn't going to be placed on both the stack and in registers,
4413 set up the register and number of words. */
4414 if (! arg->pass_on_stack)
4415 reg = arg->reg, partial = arg->partial;
4417 if (reg != 0 && partial == 0)
4418 /* Being passed entirely in a register. We shouldn't be called in
4422 /* If this arg needs special alignment, don't load the registers
4424 if (arg->n_aligned_regs != 0)
4427 /* If this is being passed partially in a register, we can't evaluate
4428 it directly into its stack slot. Otherwise, we can. */
4429 if (arg->value == 0)
4431 /* stack_arg_under_construction is nonzero if a function argument is
4432 being evaluated directly into the outgoing argument list and
4433 expand_call must take special action to preserve the argument list
4434 if it is called recursively.
4436 For scalar function arguments stack_usage_map is sufficient to
4437 determine which stack slots must be saved and restored. Scalar
4438 arguments in general have pass_on_stack == 0.
4440 If this argument is initialized by a function which takes the
4441 address of the argument (a C++ constructor or a C function
4442 returning a BLKmode structure), then stack_usage_map is
4443 insufficient and expand_call must push the stack around the
4444 function call. Such arguments have pass_on_stack == 1.
4446 Note that it is always safe to set stack_arg_under_construction,
4447 but this generates suboptimal code if set when not needed. */
4449 if (arg->pass_on_stack)
4450 stack_arg_under_construction++;
4452 arg->value = expand_expr (pval,
4454 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
4455 ? NULL_RTX : arg->stack,
4458 /* If we are promoting object (or for any other reason) the mode
4459 doesn't agree, convert the mode. */
4461 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
4462 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
4463 arg->value, arg->unsignedp);
4465 if (arg->pass_on_stack)
4466 stack_arg_under_construction--;
4469 /* Don't allow anything left on stack from computation
4470 of argument to alloca. */
4471 if (flags & ECF_MAY_BE_ALLOCA)
4472 do_pending_stack_adjust ();
4474 if (arg->value == arg->stack)
4476 /* If the value is already in the stack slot, we are done. */
4477 if (current_function_check_memory_usage && GET_CODE (arg->stack) == MEM)
4479 emit_library_call (chkr_set_right_libfunc, LCT_CONST_MAKE_BLOCK,
4480 VOIDmode, 3, XEXP (arg->stack, 0), Pmode,
4481 ARGS_SIZE_RTX (arg->size),
4482 TYPE_MODE (sizetype),
4483 GEN_INT (MEMORY_USE_RW),
4484 TYPE_MODE (integer_type_node));
4487 else if (arg->mode != BLKmode)
4491 /* Argument is a scalar, not entirely passed in registers.
4492 (If part is passed in registers, arg->partial says how much
4493 and emit_push_insn will take care of putting it there.)
4495 Push it, and if its size is less than the
4496 amount of space allocated to it,
4497 also bump stack pointer by the additional space.
4498 Note that in C the default argument promotions
4499 will prevent such mismatches. */
4501 size = GET_MODE_SIZE (arg->mode);
4502 /* Compute how much space the push instruction will push.
4503 On many machines, pushing a byte will advance the stack
4504 pointer by a halfword. */
4505 #ifdef PUSH_ROUNDING
4506 size = PUSH_ROUNDING (size);
4510 /* Compute how much space the argument should get:
4511 round up to a multiple of the alignment for arguments. */
4512 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
4513 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
4514 / (PARM_BOUNDARY / BITS_PER_UNIT))
4515 * (PARM_BOUNDARY / BITS_PER_UNIT));
4517 /* This isn't already where we want it on the stack, so put it there.
4518 This can either be done with push or copy insns. */
4519 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX, 0,
4520 partial, reg, used - size, argblock,
4521 ARGS_SIZE_RTX (arg->offset), reg_parm_stack_space,
4522 ARGS_SIZE_RTX (arg->alignment_pad));
4526 /* BLKmode, at least partly to be pushed. */
4528 register int excess;
4531 /* Pushing a nonscalar.
4532 If part is passed in registers, PARTIAL says how much
4533 and emit_push_insn will take care of putting it there. */
4535 /* Round its size up to a multiple
4536 of the allocation unit for arguments. */
4538 if (arg->size.var != 0)
4541 size_rtx = ARGS_SIZE_RTX (arg->size);
4545 /* PUSH_ROUNDING has no effect on us, because
4546 emit_push_insn for BLKmode is careful to avoid it. */
4547 excess = (arg->size.constant - int_size_in_bytes (TREE_TYPE (pval))
4548 + partial * UNITS_PER_WORD);
4549 size_rtx = expr_size (pval);
4552 if ((flags & ECF_SIBCALL) && GET_CODE (arg->value) == MEM)
4554 /* emit_push_insn might not work properly if arg->value and
4555 argblock + arg->offset areas overlap. */
4559 if (XEXP (x, 0) == current_function_internal_arg_pointer
4560 || (GET_CODE (XEXP (x, 0)) == PLUS
4561 && XEXP (XEXP (x, 0), 0) ==
4562 current_function_internal_arg_pointer
4563 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT))
4565 if (XEXP (x, 0) != current_function_internal_arg_pointer)
4566 i = INTVAL (XEXP (XEXP (x, 0), 1));
4568 /* expand_call should ensure this */
4569 if (arg->offset.var || GET_CODE (size_rtx) != CONST_INT)
4572 if (arg->offset.constant > i)
4574 if (arg->offset.constant < i + INTVAL (size_rtx))
4575 sibcall_failure = 1;
4577 else if (arg->offset.constant < i)
4579 if (i < arg->offset.constant + INTVAL (size_rtx))
4580 sibcall_failure = 1;
4585 /* If parm is passed both in stack and in register and offset is
4586 greater than reg_parm_stack_space, split the offset. */
4587 if (arg->reg && arg->pass_on_stack)
4589 if (arg->offset.constant < reg_parm_stack_space && arg->offset.var)
4590 error ("variable offset is passed paritially in stack and in reg");
4591 else if (arg->offset.constant < reg_parm_stack_space && arg->size.var)
4592 error ("variable size is passed partially in stack and in reg");
4593 else if (arg->offset.constant < reg_parm_stack_space
4594 && ((arg->offset.constant + arg->size.constant)
4595 > reg_parm_stack_space))
4597 rtx size_rtx1 = GEN_INT (reg_parm_stack_space - arg->offset.constant);
4598 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx1,
4599 TYPE_ALIGN (TREE_TYPE (pval)) / BITS_PER_UNIT,
4600 partial, reg, excess, argblock,
4601 ARGS_SIZE_RTX (arg->offset), reg_parm_stack_space,
4602 ARGS_SIZE_RTX (arg->alignment_pad));
4604 size_rtx = GEN_INT (INTVAL(size_rtx) - reg_parm_stack_space);
4609 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
4610 TYPE_ALIGN (TREE_TYPE (pval)), partial, reg, excess,
4611 argblock, ARGS_SIZE_RTX (arg->offset),
4612 reg_parm_stack_space,
4613 ARGS_SIZE_RTX (arg->alignment_pad));
4616 /* Unless this is a partially-in-register argument, the argument is now
4619 ??? Note that this can change arg->value from arg->stack to
4620 arg->stack_slot and it matters when they are not the same.
4621 It isn't totally clear that this is correct in all cases. */
4623 arg->value = arg->stack_slot;
4625 /* Once we have pushed something, pops can't safely
4626 be deferred during the rest of the arguments. */
4629 /* ANSI doesn't require a sequence point here,
4630 but PCC has one, so this will avoid some problems. */
4633 /* Free any temporary slots made in processing this argument. Show
4634 that we might have taken the address of something and pushed that
4636 preserve_temp_slots (NULL_RTX);
4640 return sibcall_failure;