| blob | 4754602e0ecda13a3a445fbd809921ddb698ccbd |
1 /* Expand builtin functions.
2 Copyright (C) 1988-2020 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
20 /* Legacy warning! Please add no further builtin simplifications here
21 (apart from pure constant folding) - builtin simplifications should go
22 to match.pd or gimple-fold.c instead. */
78 #if SWITCHABLE_TARGET
80 #endif
82 /* Define the names of the builtin function types and codes. */
86 #define DEF_BUILTIN(X, N, C, T, LT, B, F, NA, AT, IM, COND) #X,
88 {
90 };
92 /* Setup an array of builtin_info_type, make sure each element decl is
93 initialized to NULL_TREE. */
96 /* Non-zero if __builtin_constant_p should be folded right away. */
130 memop_ret retmode,
195 /* Return true if NAME starts with __builtin_ or __sync_. */
197 static bool
199 {
207 }
209 /* Return true if NODE should be considered for inline expansion regardless
210 of the optimization level. This means whenever a function is invoked with
211 its "internal" name, which normally contains the prefix "__builtin". */
213 bool
215 {
216 /* Note that we must use DECL_NAME, not DECL_ASSEMBLER_NAME_SET_P since
217 we want the name used to call the function, not the name it
218 will have. */
221 }
223 /* Compute values M and N such that M divides (address of EXP - N) and such
224 that N < M. If these numbers can be determined, store M in alignp and N in
225 *BITPOSP and return true. Otherwise return false and store BITS_PER_UNIT to
226 *alignp and any bit-offset to *bitposp.
228 Note that the address (and thus the alignment) computed here is based
229 on the address to which a symbol resolves, whereas DECL_ALIGN is based
230 on the address at which an object is actually located. These two
231 addresses are not always the same. For example, on ARM targets,
232 the address &foo of a Thumb function foo() has the lowest bit set,
233 whereas foo() itself starts on an even address.
235 If ADDR_P is true we are taking the address of the memory reference EXP
236 and thus cannot rely on the access taking place. */
238 static bool
241 {
243 tree offset;
244 machine_mode mode;
249 /* Get the innermost object and the constant (bitpos) and possibly
250 variable (offset) offset of the access. */
254 /* Extract alignment information from the innermost object and
255 possibly adjust bitpos and offset. */
257 {
258 /* Function addresses can encode extra information besides their
259 alignment. However, if TARGET_PTRMEMFUNC_VBIT_LOCATION
260 allows the low bit to be used as a virtual bit, we know
261 that the address itself must be at least 2-byte aligned. */
264 }
266 ;
268 {
269 /* The alignment of a CONST_DECL is determined by its initializer. */
276 }
278 {
281 }
285 {
291 /* If the address is explicitely aligned, handle that. */
294 {
299 }
301 known_alignment
305 /* Re-apply explicit alignment to the bitpos. */
308 /* The alignment of the pointer operand in a TARGET_MEM_REF
309 has to take the variable offset parts into account. */
311 {
313 {
318 }
322 }
324 /* When EXP is an actual memory reference then we can use
325 TYPE_ALIGN of a pointer indirection to derive alignment.
326 Do so only if get_pointer_alignment_1 did not reveal absolute
327 alignment knowledge and if using that alignment would
328 improve the situation. */
334 else
335 {
336 /* Else adjust bitpos accordingly. */
341 }
342 }
344 {
345 /* STRING_CST are the only constant objects we allow to be not
346 wrapped inside a CONST_DECL. */
352 }
354 /* If there is a non-constant offset part extract the maximum
355 alignment that can prevail. */
357 {
360 {
364 }
365 }
367 /* Account for the alignment of runtime coefficients, so that the constant
368 bitpos is guaranteed to be accurate. */
371 {
374 }
379 }
381 /* For a memory reference expression EXP compute values M and N such that M
382 divides (&EXP - N) and such that N < M. If these numbers can be determined,
383 store M in alignp and N in *BITPOSP and return true. Otherwise return false
384 and store BITS_PER_UNIT to *alignp and any bit-offset to *bitposp. */
386 bool
389 {
391 }
393 /* Return the alignment in bits of EXP, an object. */
395 unsigned int
397 {
403 /* align and bitpos now specify known low bits of the pointer.
404 ptr & (align - 1) == bitpos. */
409 }
411 /* For a pointer valued expression EXP compute values M and N such that M
412 divides (EXP - N) and such that N < M. If these numbers can be determined,
413 store M in alignp and N in *BITPOSP and return true. Return false if
414 the results are just a conservative approximation.
416 If EXP is not a pointer, false is returned too. */
418 bool
421 {
428 {
435 else
436 {
439 {
443 }
444 }
448 }
451 {
456 {
459 /* Make sure to return a sensible alignment when the multiplication
460 by BITS_PER_UNIT overflowed. */
463 /* We cannot really tell whether this result is an approximation. */
465 }
466 else
467 {
471 }
472 }
474 {
479 }
484 }
486 /* Return the alignment in bits of EXP, a pointer valued expression.
487 The alignment returned is, by default, the alignment of the thing that
488 EXP points to. If it is not a POINTER_TYPE, 0 is returned.
490 Otherwise, look at the expression to see if we can do better, i.e., if the
491 expression is actually pointing at an object whose alignment is tighter. */
493 unsigned int
495 {
501 /* align and bitpos now specify known low bits of the pointer.
502 ptr & (align - 1) == bitpos. */
508 }
510 /* Return the number of leading non-zero elements in the sequence
511 [ PTR, PTR + MAXELTS ) where each element's size is ELTSIZE bytes.
512 ELTSIZE must be a power of 2 less than 8. Used by c_strlen. */
514 unsigned
516 {
522 {
523 /* Optimize the common case of plain char. */
525 {
529 }
530 }
531 else
532 {
534 {
538 }
539 }
541 }
543 /* For a call at LOC to a function FN that expects a string in the argument
544 ARG, issue a diagnostic due to it being a called with an argument
545 declared at NONSTR that is a character array with no terminating NUL. */
547 void
549 {
557 {
561 }
562 }
564 /* For a call EXPR (which may be null) that expects a string argument
565 and SRC as the argument, returns false if SRC is a character array
566 with no terminating NUL. When nonnull, BOUND is the number of
567 characters in which to expect the terminating NUL.
568 When EXPR is nonnull also issues a warning. */
570 bool
572 {
573 tree size;
579 /* NONSTR refers to the non-nul terminated constant array and SIZE
580 is the constant size of the array in bytes. EXACT is true when
581 SIZE is exact. */
584 {
588 else
589 {
593 }
597 }
600 {
604 }
607 }
609 /* If EXP refers to an unterminated constant character array return
610 the declaration of the object of which the array is a member or
611 element and if SIZE is not null, set *SIZE to the size of
612 the unterminated array and set *EXACT if the size is exact or
613 clear it otherwise. Otherwise return null. */
615 tree
617 {
618 /* C_STRLEN will return NULL and set DECL in the info
619 structure if EXP references a unterminated array. */
620 c_strlen_data lendata = { };
623 {
625 {
628 {
629 /* Constant offsets are already accounted for in LENDATA.MINLEN,
630 but not in a SSA_NAME + CST expression. */
635 {
636 /* Subtract the offset from the size of the array. */
641 }
642 else
644 }
645 else
649 }
651 }
654 }
656 /* Compute the length of a null-terminated character string or wide
657 character string handling character sizes of 1, 2, and 4 bytes.
658 TREE_STRING_LENGTH is not the right way because it evaluates to
659 the size of the character array in bytes (as opposed to characters)
660 and because it can contain a zero byte in the middle.
662 ONLY_VALUE should be nonzero if the result is not going to be emitted
663 into the instruction stream and zero if it is going to be expanded.
664 E.g. with i++ ? "foo" : "bar", if ONLY_VALUE is nonzero, constant 3
665 is returned, otherwise NULL, since
666 len = c_strlen (ARG, 1); if (len) expand_expr (len, ...); would not
667 evaluate the side-effects.
669 If ONLY_VALUE is two then we do not emit warnings about out-of-bound
670 accesses. Note that this implies the result is not going to be emitted
671 into the instruction stream.
673 Additional information about the string accessed may be recorded
674 in DATA. For example, if ARG references an unterminated string,
675 then the declaration will be stored in the DECL field. If the
676 length of the unterminated string can be determined, it'll be
677 stored in the LEN field. Note this length could well be different
678 than what a C strlen call would return.
680 ELTSIZE is 1 for normal single byte character strings, and 2 or
681 4 for wide characer strings. ELTSIZE is by default 1.
683 The value returned is of type `ssizetype'. */
685 tree
687 {
688 /* If we were not passed a DATA pointer, then get one to a local
689 structure. That avoids having to check DATA for NULL before
690 each time we want to use it. */
691 c_strlen_data local_strlen_data = { };
700 {
707 }
715 /* Offset from the beginning of the string in bytes. */
716 tree byteoff;
717 tree memsize;
718 tree decl;
723 /* Determine the size of the string element. */
727 /* Set MAXELTS to sizeof (SRC) / sizeof (*SRC) - 1, the maximum possible
728 length of SRC. Prefer TYPE_SIZE() to TREE_STRING_LENGTH() if possible
729 in case the latter is less than the size of the array, such as when
730 SRC refers to a short string literal used to initialize a large array.
731 In that case, the elements of the array after the terminating NUL are
732 all NUL. */
741 /* PTR can point to the byte representation of any string type, including
742 char* and wchar_t*. */
746 {
747 /* The code below works only for single byte character types. */
751 /* If the string has an internal NUL character followed by any
752 non-NUL characters (e.g., "foo\0bar"), we can't compute
753 the offset to the following NUL if we don't know where to
754 start searching for it. */
757 /* Return when an embedded null character is found or none at all.
758 In the latter case, set the DECL/LEN field in the DATA structure
759 so that callers may examine them. */
763 {
768 }
770 /* For empty strings the result should be zero. */
774 /* We don't know the starting offset, but we do know that the string
775 has no internal zero bytes. If the offset falls within the bounds
776 of the string subtract the offset from the length of the string,
777 and return that. Otherwise the length is zero. Take care to
778 use SAVE_EXPR in case the OFFSET has side-effects. */
785 offsave);
789 }
791 /* Offset from the beginning of the string in elements. */
792 HOST_WIDE_INT eltoff;
794 /* We have a known offset into the string. Start searching there for
795 a null character if we can represent it as a single HOST_WIDE_INT. */
800 else
803 /* If the offset is known to be out of bounds, warn, and call strlen at
804 runtime. */
806 {
807 /* Suppress multiple warnings for propagated constant strings. */
812 eltoff))
813 {
817 }
819 }
821 /* If eltoff is larger than strelts but less than maxelts the
822 string length is zero, since the excess memory will be zero. */
826 /* Use strlen to search for the first zero byte. Since any strings
827 constructed with build_string will have nulls appended, we win even
828 if we get handed something like (char[4])"abcd".
830 Since ELTOFF is our starting index into the string, no further
831 calculation is needed. */
835 /* Don't know what to return if there was no zero termination.
836 Ideally this would turn into a gcc_checking_assert over time.
837 Set DECL/LEN so callers can examine them. */
839 {
844 }
847 }
849 /* Return a constant integer corresponding to target reading
850 GET_MODE_BITSIZE (MODE) bits from string constant STR. If
851 NULL_TERMINATED_P, reading stops after '\0' character, all further ones
852 are assumed to be zero, otherwise it reads as many characters
853 as needed. */
855 rtx
858 {
859 HOST_WIDE_INT ch;
873 {
885 }
889 }
891 /* Cast a target constant CST to target CHAR and if that value fits into
892 host char type, return zero and put that value into variable pointed to by
893 P. */
895 static int
897 {
904 /* Do not care if it fits or not right here. */
919 }
921 /* Similar to save_expr, but assumes that arbitrary code is not executed
922 in between the multiple evaluations. In particular, we assume that a
923 non-addressable local variable will not be modified. */
925 static tree
927 {
935 }
937 /* Given TEM, a pointer to a stack frame, follow the dynamic chain COUNT
938 times to get the address of either a higher stack frame, or a return
939 address located within it (depending on FNDECL_CODE). */
941 static rtx
943 {
947 {
948 /* For a zero count with __builtin_return_address, we don't care what
949 frame address we return, because target-specific definitions will
950 override us. Therefore frame pointer elimination is OK, and using
951 the soft frame pointer is OK.
953 For a nonzero count, or a zero count with __builtin_frame_address,
954 we require a stable offset from the current frame pointer to the
955 previous one, so we must use the hard frame pointer, and
956 we must disable frame pointer elimination. */
959 else
960 {
963 /* Tell reload not to eliminate the frame pointer. */
965 }
966 }
971 /* On the SPARC, the return address is not in the frame, it is in a
972 register. There is no way to access it off of the current frame
973 pointer, but it can be accessed off the previous frame pointer by
974 reading the value from the register window save area. */
976 count--;
978 /* Scan back COUNT frames to the specified frame. */
980 {
981 /* Assume the dynamic chain pointer is in the word that the
982 frame address points to, unless otherwise specified. */
987 }
989 /* For __builtin_frame_address, return what we've got. But, on
990 the SPARC for example, we may have to add a bias. */
994 /* For __builtin_return_address, get the return address from that frame. */
995 #ifdef RETURN_ADDR_RTX
997 #else
1001 #endif
1003 }
1005 /* Alias set used for setjmp buffer. */
1008 /* Construct the leading half of a __builtin_setjmp call. Control will
1009 return to RECEIVER_LABEL. This is also called directly by the SJLJ
1010 exception handling code. */
1012 void
1014 {
1016 rtx stack_save;
1017 rtx mem;
1026 /* We store the frame pointer and the address of receiver_label in
1027 the buffer and use the rest of it for the stack save area, which
1028 is machine-dependent. */
1047 /* If there is further processing to do, do it. */
1051 /* We have a nonlocal label. */
1053 }
1055 /* Construct the trailing part of a __builtin_setjmp call. This is
1056 also called directly by the SJLJ exception handling code.
1057 If RECEIVER_LABEL is NULL, instead contruct a nonlocal goto handler. */
1059 void
1061 {
1062 rtx chain;
1064 /* Mark the FP as used when we get here, so we have to make sure it's
1065 marked as used by this function. */
1068 /* Mark the static chain as clobbered here so life information
1069 doesn't get messed up for it. */
1075 {
1076 /* If the argument pointer can be eliminated in favor of the
1077 frame pointer, we don't need to restore it. We assume here
1078 that if such an elimination is present, it can always be used.
1079 This is the case on all known machines; if we don't make this
1080 assumption, we do unnecessary saving on many machines. */
1090 {
1091 /* Now restore our arg pointer from the address at which it
1092 was saved in our stack frame. */
1095 }
1096 }
1102 else
1105 /* We must not allow the code we just generated to be reordered by
1106 scheduling. Specifically, the update of the frame pointer must
1107 happen immediately, not later. */
1109 }
1111 /* __builtin_longjmp is passed a pointer to an array of five words (not
1112 all will be used on all machines). It operates similarly to the C
1113 library function of the same name, but is more efficient. Much of
1114 the code below is copied from the handling of non-local gotos. */
1116 static void
1118 {
1123 /* DRAP is needed for stack realign if longjmp is expanded to current
1124 function */
1135 /* We require that the user must pass a second argument of 1, because
1136 that is what builtin_setjmp will return. */
1142 else
1143 {
1154 /* Pick up FP, label, and SP from the block and jump. This code is
1155 from expand_goto in stmt.c; see there for detailed comments. */
1157 /* We have to pass a value to the nonlocal_goto pattern that will
1158 get copied into the static_chain pointer, but it does not matter
1159 what that value is, because builtin_setjmp does not use it. */
1161 else
1162 {
1168 /* Restore the frame pointer and stack pointer. We must use a
1169 temporary since the setjmp buffer may be a local. */
1173 /* Ensure the frame pointer move is not optimized. */
1182 }
1183 }
1185 /* Search backwards and mark the jump insn as a non-local goto.
1186 Note that this precludes the use of __builtin_longjmp to a
1187 __builtin_setjmp target in the same function. However, we've
1188 already cautioned the user that these functions are for
1189 internal exception handling use only. */
1191 {
1195 {
1198 }
1201 }
1202 }
1206 {
1208 }
1210 /* This function validates the types of a function call argument list
1211 against a specified list of tree_codes. If the last specifier is a 0,
1212 that represents an ellipsis, otherwise the last specifier must be a
1213 VOID_TYPE. */
1215 static bool
1217 {
1221 const_call_expr_arg_iterator iter;
1222 const_tree arg;
1227 /* Get a bitmap of pointer argument numbers declared attribute nonnull. */
1232 {
1236 {
1238 /* This signifies an ellipses, any further arguments are all ok. */
1242 /* This signifies an endlink, if no arguments remain, return
1243 true, otherwise return false. */
1247 /* The actual argument must be nonnull when either the whole
1248 called function has been declared nonnull, or when the formal
1249 argument corresponding to the actual argument has been. */
1252 {
1257 }
1258 /* FALLTHRU */
1260 /* If no parameters remain or the parameter's code does not
1261 match the specified code, return false. Otherwise continue
1262 checking any remaining arguments. */
1267 }
1268 }
1270 /* We need gotos here since we can only have one VA_CLOSE in a
1271 function. */
1272 end: ;
1278 }
1280 /* Expand a call to __builtin_nonlocal_goto. We're passed the target label
1281 and the address of the save area. */
1283 static rtx
1285 {
1300 /* Copy the address of the save location to a register just in case it was
1301 based on the frame pointer. */
1310 /* ??? We no longer need to pass the static chain value, afaik. */
1313 else
1314 {
1320 /* Restore the frame pointer and stack pointer. We must use a
1321 temporary since the setjmp buffer may be a local. */
1325 /* Ensure the frame pointer move is not optimized. */
1331 /* USE of hard_frame_pointer_rtx added for consistency;
1332 not clear if really needed. */
1336 /* If the architecture is using a GP register, we must
1337 conservatively assume that the target function makes use of it.
1338 The prologue of functions with nonlocal gotos must therefore
1339 initialize the GP register to the appropriate value, and we
1340 must then make sure that this value is live at the point
1341 of the jump. (Note that this doesn't necessarily apply
1342 to targets with a nonlocal_goto pattern; they are free
1343 to implement it in their own way. Note also that this is
1344 a no-op if the GP register is a global invariant.) */
1350 }
1352 /* Search backwards to the jump insn and mark it as a
1353 non-local goto. */
1355 {
1357 {
1360 }
1363 }
1366 }
1368 /* __builtin_update_setjmp_buf is passed a pointer to an array of five words
1369 (not all will be used on all machines) that was passed to __builtin_setjmp.
1370 It updates the stack pointer in that block to the current value. This is
1371 also called directly by the SJLJ exception handling code. */
1373 void
1375 {
1378 rtx stack_save
1380 memory_address
1386 }
1388 /* Expand a call to __builtin_prefetch. For a target that does not support
1389 data prefetch, evaluate the memory address argument in case it has side
1390 effects. */
1392 static void
1394 {
1404 /* Arguments 1 and 2 are optional; argument 1 (read/write) defaults to
1405 zero (read) and argument 2 (locality) defaults to 3 (high degree of
1406 locality). */
1410 else
1414 else
1417 /* Argument 0 is an address. */
1420 /* Argument 1 (read/write flag) must be a compile-time constant int. */
1422 {
1425 }
1427 /* Argument 1 must be either zero or one. */
1429 {
1433 }
1435 /* Argument 2 (locality) must be a compile-time constant int. */
1437 {
1440 }
1442 /* Argument 2 must be 0, 1, 2, or 3. */
1444 {
1447 }
1450 {
1458 }
1460 /* Don't do anything with direct references to volatile memory, but
1461 generate code to handle other side effects. */
1464 }
1466 /* Get a MEM rtx for expression EXP which is the address of an operand
1467 to be used in a string instruction (cmpstrsi, cpymemsi, ..). LEN is
1468 the maximum length of the block of memory that might be accessed or
1469 NULL if unknown. */
1471 static rtx
1473 {
1477 /* When EXP is not resolved SAVE_EXPR, MEM_ATTRS can be still derived
1478 from its expression, for expr->a.b only <variable>.a.b is recorded. */
1485 /* Get an expression we can use to find the attributes to assign to MEM.
1486 First remove any nops. */
1491 /* Build a MEM_REF representing the whole accessed area as a byte blob,
1492 (as builtin stringops may alias with anything). */
1499 /* If the MEM_REF has no acceptable address, try to get the base object
1500 from the original address we got, and build an all-aliasing
1501 unknown-sized access to that one. */
1507 {
1512 size_zero_node,
1513 NULL)),
1516 }
1519 }
1520 \f
1521 /* Built-in functions to perform an untyped call and return. */
1523 #define apply_args_mode \
1524 (this_target_builtins->x_apply_args_mode)
1525 #define apply_result_mode \
1526 (this_target_builtins->x_apply_result_mode)
1528 /* Return the size required for the block returned by __builtin_apply_args,
1529 and initialize apply_args_mode. */
1531 static int
1533 {
1538 /* The values computed by this function never change. */
1540 {
1541 /* The first value is the incoming arg-pointer. */
1544 /* The second value is the structure value address unless this is
1545 passed as an "invisible" first argument. */
1551 {
1561 }
1562 else
1563 {
1565 }
1566 }
1568 }
1570 /* Return the size required for the block returned by __builtin_apply,
1571 and initialize apply_result_mode. */
1573 static int
1575 {
1579 /* The values computed by this function never change. */
1581 {
1586 {
1596 }
1597 else
1600 /* Allow targets that use untyped_call and untyped_return to override
1601 the size so that machine-specific information can be stored here. */
1602 #ifdef APPLY_RESULT_SIZE
1604 #endif
1605 }
1607 }
1609 /* Create a vector describing the result block RESULT. If SAVEP is true,
1610 the result block is used to save the values; otherwise it is used to
1611 restore the values. */
1613 static rtx
1615 {
1617 fixed_size_mode mode;
1624 {
1634 }
1636 }
1638 /* Save the state required to perform an untyped call with the same
1639 arguments as were passed to the current function. */
1641 static rtx
1643 {
1646 fixed_size_mode mode;
1647 rtx struct_incoming_value = targetm.calls.struct_value_rtx (cfun ? TREE_TYPE (cfun->decl) : 0, 1);
1649 /* Create a block where the arg-pointer, structure value address,
1650 and argument registers can be saved. */
1653 /* Walk past the arg-pointer and structure value address. */
1658 /* Save each register used in calling a function to the block. */
1661 {
1670 }
1672 /* Save the arg pointer to the block. */
1674 /* We need the pointer as the caller actually passed them to us, not
1675 as we might have pretended they were passed. Make sure it's a valid
1676 operand, as emit_move_insn isn't expected to handle a PLUS. */
1678 tem
1681 NULL_RTX);
1686 /* Save the structure value address unless this is passed as an
1687 "invisible" first argument. */
1692 /* Return the address of the block. */
1694 }
1696 /* __builtin_apply_args returns block of memory allocated on
1697 the stack into which is stored the arg pointer, structure
1698 value address, static chain, and all the registers that might
1699 possibly be used in performing a function call. The code is
1700 moved to the start of the function so the incoming values are
1701 saved. */
1703 static rtx
1705 {
1706 /* Don't do __builtin_apply_args more than once in a function.
1707 Save the result of the first call and reuse it. */
1710 {
1711 /* When this function is called, it means that registers must be
1712 saved on entry to this function. So we migrate the
1713 call to the first insn of this function. */
1714 rtx temp;
1723 /* Put the insns after the NOTE that starts the function.
1724 If this is inside a start_sequence, make the outer-level insn
1725 chain current, so the code is placed at the start of the
1726 function. If internal_arg_pointer is a non-virtual pseudo,
1727 it needs to be placed after the function that initializes
1728 that pseudo. */
1733 else
1737 }
1738 }
1740 /* Perform an untyped call and save the state required to perform an
1741 untyped return of whatever value was returned by the given function. */
1743 static rtx
1745 {
1747 fixed_size_mode mode;
1756 /* Create a block where the return registers can be saved. */
1759 /* Fetch the arg pointer from the ARGUMENTS block. */
1766 /* Push a new argument block and copy the arguments. Do not allow
1767 the (potential) memcpy call below to interfere with our stack
1768 manipulations. */
1770 NO_DEFER_POP;
1772 /* Save the stack with nonlocal if available. */
1775 else
1778 /* Allocate a block of memory onto the stack and copy the memory
1779 arguments to the outgoing arguments address. We can pass TRUE
1780 as the 4th argument because we just saved the stack pointer
1781 and will restore it right after the call. */
1784 /* Set DRAP flag to true, even though allocate_dynamic_stack_space
1785 may have already set current_function_calls_alloca to true.
1786 current_function_calls_alloca won't be set if argsize is zero,
1787 so we have to guarantee need_drap is true here. */
1793 {
1796 else
1798 }
1805 /* Refer to the argument block. */
1810 /* Walk past the arg-pointer and structure value address. */
1815 /* Restore each of the registers previously saved. Make USE insns
1816 for each of these registers for use in making the call. */
1819 {
1827 }
1829 /* Restore the structure value address unless this is passed as an
1830 "invisible" first argument. */
1833 {
1839 }
1841 /* All arguments and registers used for the call are set up by now! */
1844 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
1845 and we don't want to load it into a register as an optimization,
1846 because prepare_call_address already did it if it should be done. */
1850 /* Generate the actual call instruction and save the return value. */
1852 {
1856 }
1858 {
1861 /* Locate the unique return register. It is not possible to
1862 express a call that sets more than one return register using
1863 call_value; use untyped_call for that. In fact, untyped_call
1864 only needs to save the return registers in the given block. */
1867 {
1871 }
1878 }
1879 else
1882 /* Find the CALL insn we just emitted, and attach the register usage
1883 information. */
1887 /* Restore the stack. */
1890 else
1894 OK_DEFER_POP;
1896 /* Return the address of the result block. */
1899 }
1901 /* Perform an untyped return. */
1903 static void
1905 {
1907 fixed_size_mode mode;
1908 rtx reg;
1917 {
1922 }
1924 /* Restore the return value and note that each value is used. */
1928 {
1940 }
1942 /* Put the USE insns before the return. */
1945 /* Return whatever values was restored by jumping directly to the end
1946 of the function. */
1948 }
1950 /* Used by expand_builtin_classify_type and fold_builtin_classify_type. */
1952 static enum type_class
1954 {
1956 {
1975 }
1976 }
1978 /* Expand a call EXP to __builtin_classify_type. */
1980 static rtx
1982 {
1986 }
1988 /* This helper macro, meant to be used in mathfn_built_in below, determines
1989 which among a set of builtin math functions is appropriate for a given type
1990 mode. The `F' (float) and `L' (long double) are automatically generated
1991 from the 'double' case. If a function supports the _Float<N> and _Float<N>X
1992 types, there are additional types that are considered with 'F32', 'F64',
1993 'F128', etc. suffixes. */
1994 #define CASE_MATHFN(MATHFN) \
1995 CASE_CFN_##MATHFN: \
1996 fcode = BUILT_IN_##MATHFN; fcodef = BUILT_IN_##MATHFN##F ; \
1997 fcodel = BUILT_IN_##MATHFN##L ; break;
1998 /* Similar to the above, but also add support for the _Float<N> and _Float<N>X
1999 types. */
2000 #define CASE_MATHFN_FLOATN(MATHFN) \
2001 CASE_CFN_##MATHFN: \
2002 fcode = BUILT_IN_##MATHFN; fcodef = BUILT_IN_##MATHFN##F ; \
2003 fcodel = BUILT_IN_##MATHFN##L ; fcodef16 = BUILT_IN_##MATHFN##F16 ; \
2004 fcodef32 = BUILT_IN_##MATHFN##F32; fcodef64 = BUILT_IN_##MATHFN##F64 ; \
2005 fcodef128 = BUILT_IN_##MATHFN##F128 ; fcodef32x = BUILT_IN_##MATHFN##F32X ; \
2006 fcodef64x = BUILT_IN_##MATHFN##F64X ; fcodef128x = BUILT_IN_##MATHFN##F128X ;\
2007 break;
2008 /* Similar to above, but appends _R after any F/L suffix. */
2009 #define CASE_MATHFN_REENT(MATHFN) \
2010 case CFN_BUILT_IN_##MATHFN##_R: \
2011 case CFN_BUILT_IN_##MATHFN##F_R: \
2012 case CFN_BUILT_IN_##MATHFN##L_R: \
2013 fcode = BUILT_IN_##MATHFN##_R; fcodef = BUILT_IN_##MATHFN##F_R ; \
2014 fcodel = BUILT_IN_##MATHFN##L_R ; break;
2016 /* Return a function equivalent to FN but operating on floating-point
2017 values of type TYPE, or END_BUILTINS if no such function exists.
2018 This is purely an operation on function codes; it does not guarantee
2019 that the target actually has an implementation of the function. */
2021 static built_in_function
2023 {
2024 tree mtype;
2035 {
2127 }
2150 else
2152 }
2154 /* Return mathematic function equivalent to FN but operating directly on TYPE,
2155 if available. If IMPLICIT_P is true use the implicit builtin declaration,
2156 otherwise use the explicit declaration. If we can't do the conversion,
2157 return null. */
2159 static tree
2161 {
2170 }
2172 /* Like mathfn_built_in_1, but always use the implicit array. */
2174 tree
2176 {
2178 }
2180 /* Like mathfn_built_in_1, but take a built_in_function and
2181 always use the implicit array. */
2183 tree
2185 {
2187 }
2189 /* If BUILT_IN_NORMAL function FNDECL has an associated internal function,
2190 return its code, otherwise return IFN_LAST. Note that this function
2191 only tests whether the function is defined in internals.def, not whether
2192 it is actually available on the target. */
2194 internal_fn
2196 {
2200 {
2201 #define DEF_INTERNAL_FLT_FN(NAME, FLAGS, OPTAB, TYPE) \
2202 CASE_FLT_FN (BUILT_IN_##NAME): return IFN_##NAME;
2203 #define DEF_INTERNAL_FLT_FLOATN_FN(NAME, FLAGS, OPTAB, TYPE) \
2204 CASE_FLT_FN (BUILT_IN_##NAME): return IFN_##NAME; \
2205 CASE_FLT_FN_FLOATN_NX (BUILT_IN_##NAME): return IFN_##NAME;
2206 #define DEF_INTERNAL_INT_FN(NAME, FLAGS, OPTAB, TYPE) \
2207 CASE_INT_FN (BUILT_IN_##NAME): return IFN_##NAME;
2224 }
2225 }
2227 /* If CALL is a call to a BUILT_IN_NORMAL function that could be replaced
2228 on the current target by a call to an internal function, return the
2229 code of that internal function, otherwise return IFN_LAST. The caller
2230 is responsible for ensuring that any side-effects of the built-in
2231 call are dealt with correctly. E.g. if CALL sets errno, the caller
2232 must decide that the errno result isn't needed or make it available
2233 in some other way. */
2235 internal_fn
2237 {
2239 {
2242 {
2247 }
2248 }
2250 }
2252 /* Expand a call to the builtin trinary math functions (fma).
2253 Return NULL_RTX if a normal call should be emitted rather than expanding the
2254 function in-line. EXP is the expression that is a call to the builtin
2255 function; if convenient, the result should be placed in TARGET.
2256 SUBTARGET may be used as the target for computing one of EXP's
2257 operands. */
2259 static rtx
2261 {
2262 optab builtin_optab;
2267 machine_mode mode;
2277 {
2283 }
2285 /* Make a suitable register to place result in. */
2288 /* Before working hard, check whether the instruction is available. */
2294 /* Always stabilize the argument list. */
2305 /* Compute into RESULT.
2306 Set RESULT to wherever the result comes back. */
2310 /* If we were unable to expand via the builtin, stop the sequence
2311 (without outputting the insns) and call to the library function
2312 with the stabilized argument list. */
2314 {
2317 }
2319 /* Output the entire sequence. */
2325 }
2327 /* Expand a call to the builtin sin and cos math functions.
2328 Return NULL_RTX if a normal call should be emitted rather than expanding the
2329 function in-line. EXP is the expression that is a call to the builtin
2330 function; if convenient, the result should be placed in TARGET.
2331 SUBTARGET may be used as the target for computing one of EXP's
2332 operands. */
2334 static rtx
2336 {
2337 optab builtin_optab;
2338 rtx op0;
2341 machine_mode mode;
2342 tree arg;
2350 {
2356 }
2358 /* Make a suitable register to place result in. */
2361 /* Check if sincos insn is available, otherwise fallback
2362 to sin or cos insn. */
2365 {
2372 }
2374 /* Before working hard, check whether the instruction is available. */
2376 {
2379 /* Wrap the computation of the argument in a SAVE_EXPR, as we may
2380 need to expand the argument again. This way, we will not perform
2381 side-effects more the once. */
2388 /* Compute into RESULT.
2389 Set RESULT to wherever the result comes back. */
2391 {
2395 {
2404 }
2406 }
2407 else
2411 {
2412 /* Output the entire sequence. */
2417 }
2419 /* If we were unable to expand via the builtin, stop the sequence
2420 (without outputting the insns) and call to the library function
2421 with the stabilized argument list. */
2423 }
2426 }
2428 /* Given an interclass math builtin decl FNDECL and it's argument ARG
2429 return an RTL instruction code that implements the functionality.
2430 If that isn't possible or available return CODE_FOR_nothing. */
2432 static enum insn_code
2434 {
2437 machine_mode mode;
2440 {
2454 /* These builtins have no optabs (yet). */
2458 }
2460 /* There's no easy way to detect the case we need to set EDOM. */
2464 /* Optab mode depends on the mode of the input argument. */
2470 }
2472 /* Expand a call to one of the builtin math functions that operate on
2473 floating point argument and output an integer result (ilogb, isinf,
2474 isnan, etc).
2475 Return 0 if a normal call should be emitted rather than expanding the
2476 function in-line. EXP is the expression that is a call to the builtin
2477 function; if convenient, the result should be placed in TARGET. */
2479 static rtx
2481 {
2483 rtx op0;
2485 machine_mode mode;
2486 tree arg;
2496 {
2501 /* Wrap the computation of the argument in a SAVE_EXPR, as we may
2502 need to expand the argument again. This way, we will not perform
2503 side-effects more the once. */
2518 }
2521 }
2523 /* Expand a call to the builtin sincos math function.
2524 Return NULL_RTX if a normal call should be emitted rather than expanding the
2525 function in-line. EXP is the expression that is a call to the builtin
2526 function. */
2528 static rtx
2530 {
2532 machine_mode mode;
2546 /* Make a suitable register to place result in. */
2549 /* Check if sincos insn is available, otherwise emit the call. */
2564 /* Compute into target1 and target2.
2565 Set TARGET to wherever the result comes back. */
2569 /* Move target1 and target2 to the memory locations indicated
2570 by op1 and op2. */
2575 }
2577 /* Expand a call to the internal cexpi builtin to the sincos math function.
2578 EXP is the expression that is a call to the builtin function; if convenient,
2579 the result should be placed in TARGET. */
2581 static rtx
2583 {
2586 machine_mode mode;
2597 /* Try expanding via a sincos optab, fall back to emitting a libcall
2598 to sincos or cexp. We are sure we have sincos or cexp because cexpi
2599 is only generated from sincos, cexp or if we have either of them. */
2601 {
2607 /* Compute into op1 and op2. */
2609 }
2611 {
2622 else
2632 /* Make sure not to fold the sincos call again. */
2636 }
2637 else
2638 {
2648 else
2651 /* If we don't have a decl for cexp create one. This is the
2652 friendliest fallback if the user calls __builtin_cexpi
2653 without full target C99 function support. */
2655 {
2656 tree fntype;
2668 }
2673 /* Make sure not to fold the cexp call again. */
2677 }
2679 /* Now build the proper return type. */
2684 }
2686 /* Conveniently construct a function call expression. FNDECL names the
2687 function to be called, N is the number of arguments, and the "..."
2688 parameters are the argument expressions. Unlike build_call_exr
2689 this doesn't fold the call, hence it will always return a CALL_EXPR. */
2691 static tree
2693 {
2703 }
2705 /* Expand a call to one of the builtin rounding functions gcc defines
2706 as an extension (lfloor and lceil). As these are gcc extensions we
2707 do not need to worry about setting errno to EDOM.
2708 If expanding via optab fails, lower expression to (int)(floor(x)).
2709 EXP is the expression that is a call to the builtin function;
2710 if convenient, the result should be placed in TARGET. */
2712 static rtx
2714 {
2715 convert_optab builtin_optab;
2720 tree fallback_fndecl;
2721 machine_mode mode;
2722 tree arg;
2730 {
2747 }
2749 /* Make a suitable register to place result in. */
2754 /* Wrap the computation of the argument in a SAVE_EXPR, as we may
2755 need to expand the argument again. This way, we will not perform
2756 side-effects more the once. */
2763 /* Compute into TARGET. */
2765 {
2766 /* Output the entire sequence. */
2771 }
2773 /* If we were unable to expand via the builtin, stop the sequence
2774 (without outputting the insns). */
2777 /* Fall back to floating point rounding optab. */
2780 /* For non-C99 targets we may end up without a fallback fndecl here
2781 if the user called __builtin_lfloor directly. In this case emit
2782 a call to the floor/ceil variants nevertheless. This should result
2783 in the best user experience for not full C99 targets. */
2785 {
2786 tree fntype;
2790 {
2823 }
2828 }
2835 /* Truncate the result of floating point optab to integer
2836 via expand_fix (). */
2841 }
2843 /* Expand a call to one of the builtin math functions doing integer
2844 conversion (lrint).
2845 Return 0 if a normal call should be emitted rather than expanding the
2846 function in-line. EXP is the expression that is a call to the builtin
2847 function; if convenient, the result should be placed in TARGET. */
2849 static rtx
2851 {
2852 convert_optab builtin_optab;
2853 rtx op0;
2856 tree arg;
2857 machine_mode mode;
2866 {
2885 }
2887 /* There's no easy way to detect the case we need to set EDOM. */
2891 /* Make a suitable register to place result in. */
2894 /* There's no easy way to detect the case we need to set EDOM. */
2896 {
2899 /* Wrap the computation of the argument in a SAVE_EXPR, as we may
2900 need to expand the argument again. This way, we will not perform
2901 side-effects more the once. */
2909 {
2910 /* Output the entire sequence. */
2915 }
2917 /* If we were unable to expand via the builtin, stop the sequence
2918 (without outputting the insns) and call to the library function
2919 with the stabilized argument list. */
2921 }
2924 {
2925 /* Fall back to rounding to long int. Use implicit_p 0 - for non-C99
2926 targets, (int) round (x) should never be transformed into
2927 BUILT_IN_IROUND and if __builtin_iround is called directly, emit
2928 a call to lround in the hope that the target provides at least some
2929 C99 functions. This should result in the best user experience for
2930 not full C99 targets. */
2931 tree fallback_fndecl = mathfn_built_in_1
2940 }
2943 }
2945 /* Expand a call to the powi built-in mathematical function. Return NULL_RTX if
2946 a normal call should be emitted rather than expanding the function
2947 in-line. EXP is the expression that is a call to the builtin
2948 function; if convenient, the result should be placed in TARGET. */
2950 static rtx
2952 {
2955 machine_mode mode;
2956 machine_mode mode2;
2965 /* Emit a libcall to libgcc. */
2967 /* Mode of the 2nd argument must match that of an int. */
2985 }
2987 /* Expand expression EXP which is a call to the strlen builtin. Return
2988 NULL_RTX if we failed and the caller should emit a normal call, otherwise
2989 try to get the result in TARGET, if convenient. */
2991 static rtx
2993 machine_mode target_mode)
2994 {
2999 rtx pat;
3000 tree len;
3002 rtx src_reg;
3004 machine_mode insn_mode;
3008 /* If the length can be computed at compile-time, return it. */
3013 /* If the length can be computed at compile-time and is constant
3014 integer, but there are side-effects in src, evaluate
3015 src for side-effects, then return len.
3016 E.g. x = strlen (i++ ? "xfoo" + 1 : "bar");
3017 can be optimized into: i++; x = 3; */
3020 {
3023 }
3027 /* If SRC is not a pointer type, don't do this operation inline. */
3031 /* Bail out if we can't compute strlen in the right mode. */
3033 {
3037 }
3041 /* Make a place to hold the source address. We will not expand
3042 the actual source until we are sure that the expansion will
3043 not fail -- there are trees that cannot be expanded twice. */
3046 /* Mark the beginning of the strlen sequence so we can emit the
3047 source operand later. */
3057 /* Check to see if the argument was declared attribute nonstring
3058 and if so, issue a warning since at this point it's not known
3059 to be nul-terminated. */
3062 /* Now that we are assured of success, expand the source. */
3066 {
3067 #ifdef POINTERS_EXTEND_UNSIGNED
3070 POINTERS_EXTEND_UNSIGNED);
3071 #endif
3073 }
3079 else
3082 /* Return the value in the proper mode for this function. */
3087 else
3091 }
3093 /* Expand call EXP to the strnlen built-in, returning the result
3094 and setting it in TARGET. Otherwise return NULL_RTX on failure. */
3096 static rtx
3098 {
3115 /* FIXME: Change c_strlen() to return sizetype instead of ssizetype
3116 so these conversions aren't necessary. */
3117 c_strlen_data lendata = { };
3123 {
3127 "%K%qD specified bound %E "
3134 {
3135 /* Clear EXACT if LEN may be less than SRC suggests,
3136 such as in
3137 strnlen (&a[i], sizeof a)
3138 where the value of i is unknown. Unless i's value is
3139 zero, the call is unsafe because the bound is greater. */
3143 }
3146 {
3147 location_t warnloc
3152 exact
3158 {
3162 }
3164 }
3171 }
3184 "%K%qD specified bound [%wu, %wu] "
3191 {
3195 }
3201 {
3202 location_t warnloc
3206 exact
3212 {
3216 }
3217 }
3227 }
3229 /* Callback routine for store_by_pieces. Read GET_MODE_BITSIZE (MODE)
3230 bytes from constant string DATA + OFFSET and return it as target
3231 constant. */
3233 static rtx
3235 scalar_int_mode mode)
3236 {
3244 }
3246 /* LEN specify length of the block of memcpy/memset operation.
3247 Figure out its range and put it into MIN_SIZE/MAX_SIZE.
3248 In some cases we can make very likely guess on max size, then we
3249 set it into PROBABLE_MAX_SIZE. */
3251 static void
3256 {
3258 {
3261 }
3262 else
3263 {
3267 /* Determine bounds from the type. */
3270 else
3275 else
3281 {
3286 }
3288 {
3289 /* Anti range 0...N lets us to determine minimal size to N+1. */
3291 {
3294 }
3295 /* Code like
3297 int n;
3298 if (n < 100)
3299 memcpy (a, b, n)
3301 Produce anti range allowing negative values of N. We still
3302 can use the information and make a guess that N is not negative.
3303 */
3306 }
3307 }
3311 }
3313 /* For an expression EXP issue an access warning controlled by option OPT
3314 with access to a region SLEN bytes in size in the RANGE of sizes. */
3316 static bool
3319 {
3323 {
3325 warned = (func
3335 {
3336 /* Avoid printing the upper bound if it's invalid. */
3337 warned = (func
3339 "%K%qD reading %E or more bytes from a region "
3343 "%Kreading %E or more bytes from a region "
3346 }
3347 else
3348 warned = (func
3350 "%K%qD reading between %E and %E bytes from "
3354 "%Kreading between %E and %E bytes from "
3359 }
3362 warned = (func
3372 {
3373 /* Avoid printing the upper bound if it's invalid. */
3374 warned = (func
3376 "%K%qD expecting %E or more bytes in a region "
3380 "%Kexpecting %E or more bytes in a region "
3383 }
3384 else
3385 warned = (func
3387 "%K%qD expecting between %E and %E bytes in "
3391 "%Kexpectting between %E and %E bytes in "
3395 }
3397 /* Issue an inform message describing the target of an access REF.
3398 WRITE is set for a write access and clear for a read access. */
3400 static void
3402 {
3406 /* Convert offset range and avoid including a zero range since it isn't
3407 necessarily meaningful. */
3411 {
3414 }
3416 /* Convert size range and always include it since all sizes are
3417 meaningful. */
3421 {
3424 }
3427 location_t loc;
3430 {
3436 /* Handle calls through pointers to functions. */
3439 /* SIZRNG doesn't necessarily have the same range as the allocation
3440 size determined by gimple_call_alloc_size (). */
3444 else
3447 }
3448 else
3452 {
3454 {
3456 {
3459 else
3462 }
3463 else
3467 }
3470 {
3474 else
3476 "at offset %lli into destination object of size %s "
3478 }
3479 else
3481 "at offset [%lli, %lli] into destination object of size %s "
3486 }
3489 {
3491 {
3494 else
3497 }
3498 else
3502 }
3505 {
3509 else
3511 "at offset %lli into source object of size %s "
3513 }
3514 else
3516 "at offset [%lli, %lli] into source object of size %s "
3519 }
3521 /* Try to verify that the sizes and lengths of the arguments to a string
3522 manipulation function given by EXP are within valid bounds and that
3523 the operation does not lead to buffer overflow or read past the end.
3524 Arguments other than EXP may be null. When non-null, the arguments
3525 have the following meaning:
3526 DST is the destination of a copy call or NULL otherwise.
3527 SRC is the source of a copy call or NULL otherwise.
3528 DSTWRITE is the number of bytes written into the destination obtained
3529 from the user-supplied size argument to the function (such as in
3530 memcpy(DST, SRCs, DSTWRITE) or strncpy(DST, DRC, DSTWRITE).
3531 MAXREAD is the user-supplied bound on the length of the source sequence
3532 (such as in strncat(d, s, N). It specifies the upper limit on the number
3533 of bytes to write. If NULL, it's taken to be the same as DSTWRITE.
3534 SRCSTR is the source string (such as in strcpy(DST, SRC)) when the
3535 expression EXP is a string function call (as opposed to a memory call
3536 like memcpy). As an exception, SRCSTR can also be an integer denoting
3537 the precomputed size of the source string or object (for functions like
3538 memcpy).
3539 DSTSIZE is the size of the destination object specified by the last
3540 argument to the _chk builtins, typically resulting from the expansion
3541 of __builtin_object_size (such as in __builtin___strcpy_chk(DST, SRC,
3542 DSTSIZE).
3544 When DSTWRITE is null LEN is checked to verify that it doesn't exceed
3545 SIZE_MAX.
3547 ACCESS is true for accesses, false for simple size checks in calls
3548 to functions that neither read from nor write to the region.
3550 When nonnull, PAD points to a more detailed description of the access.
3552 If the call is successfully verified as safe return true, otherwise
3553 return false. */
3555 bool
3560 {
3563 /* The size of the largest object is half the address space, or
3564 PTRDIFF_MAX. (This is way too permissive.) */
3567 /* Either the length of the source string for string functions or
3568 the size of the source object for raw memory functions. */
3573 /* Set to true when the exact number of bytes written by a string
3574 function like strcpy is not known and the only thing that is
3575 known is that it must be at least one (for the terminating nul). */
3578 {
3579 /* SRCSTR is normally a pointer to string but as a special case
3580 it can be an integer denoting the length of a string. */
3582 {
3583 /* Try to determine the range of lengths the source string
3584 refers to. If it can be determined and is less than
3585 the upper bound given by MAXREAD add one to it for
3586 the terminating nul. Otherwise, set it to one for
3587 the same reason, or to MAXREAD as appropriate. */
3588 c_strlen_data lendata = { };
3593 {
3596 else
3607 }
3608 else
3609 {
3612 }
3613 }
3614 else
3616 }
3619 {
3620 /* When the only available piece of data is the object size
3621 there is nothing to do. */
3625 /* Otherwise, when the length of the source sequence is known
3626 (as with strlen), set DSTWRITE to it. */
3629 }
3639 /* First check the number of bytes to be written against the maximum
3640 object size. */
3644 {
3653 warned = (func
3655 "%K%qD specified size %E "
3659 "%Kspecified size %E "
3662 else
3663 warned = (func
3665 "%K%qD specified size between %E and %E "
3670 "%Kspecified size between %E and %E "
3677 }
3679 /* The number of bytes to write is "exact" if DSTWRITE is non-null,
3680 constant, and in range of unsigned HOST_WIDE_INT. */
3683 /* Next check the number of bytes to be written against the destination
3684 object size. */
3686 {
3691 || (dstwrite
3694 {
3703 {
3704 /* This is a call to strcpy with a destination of 0 size
3705 and a source of unknown length. The call will write
3706 at least one byte past the end of the destination. */
3707 warned = (func
3709 "%K%qD writing %E or more bytes into "
3710 "a region of size %E overflows "
3714 "%Kwriting %E or more bytes into "
3715 "a region of size %E overflows "
3718 }
3720 warned = (func
3722 "%K%qD writing %E byte into a region "
3724 "%K%qD writing %E bytes into a region "
3728 "%Kwriting %E byte into a region "
3730 "%Kwriting %E bytes into a region "
3734 {
3735 /* Avoid printing the upper bound if it's invalid. */
3736 warned = (func
3738 "%K%qD writing %E or more bytes into "
3739 "a region of size %E overflows "
3743 "%Kwriting %E or more bytes into "
3744 "a region of size %E overflows "
3747 }
3748 else
3749 warned = (func
3751 "%K%qD writing between %E and %E bytes "
3752 "into a region of size %E overflows "
3755 dstsize)
3757 "%Kwriting between %E and %E bytes "
3758 "into a region of size %E overflows "
3761 dstsize));
3763 {
3767 }
3769 /* Return error when an overflow has been detected. */
3771 }
3772 }
3774 /* Check the maximum length of the source sequence against the size
3775 of the destination object if known, or against the maximum size
3776 of an object. */
3778 {
3781 {
3786 {
3792 /* Warn about crazy big sizes first since that's more
3793 likely to be meaningful than saying that the bound
3794 is greater than the object size if both are big. */
3796 warned = (func
3798 "%K%qD specified bound %E "
3802 "%Kspecified bound %E "
3805 else
3806 warned = (func
3808 "%K%qD specified bound between "
3809 "%E and %E exceeds maximum object "
3814 "%Kspecified bound between "
3815 "%E and %E exceeds maximum object "
3822 }
3825 {
3832 warned = (func
3834 "%K%qD specified bound %E "
3839 "%Kspecified bound %E "
3842 else
3843 warned = (func
3845 "%K%qD specified bound between %E "
3850 "%Kspecified bound between %E "
3852 exp,
3858 }
3859 }
3860 }
3862 /* Check for reading past the end of SRC. */
3867 {
3875 {
3879 }
3881 }
3884 }
3886 /* If STMT is a call to an allocation function, returns the constant
3887 size of the object allocated by the call represented as sizetype.
3888 If nonnull, sets RNG1[] to the range of the size. */
3890 tree
3893 {
3897 tree allocfntype;
3900 else
3909 {
3914 }
3919 {
3930 {
3934 }
3935 }
3940 /* If RNG1 is not set, use the buffer. */
3950 /* To handle ranges do the math in wide_int and return the product
3951 of the upper bounds as a constant. Ignore anti-ranges. */
3957 /* Extend to the maximum precision to avoid overflow. */
3964 /* Compute products of both bounds for the caller but return the lesser
3965 of SIZE_MAX and the product of the upper bounds as a constant. */
3970 {
3973 }
3976 }
3978 /* Wrapper around the wide_int overload of get_range. Returns the same
3979 result but accepts offset_int instead. */
3981 static bool
3984 {
3992 }
3994 /* Helper to compute the size of the object referenced by the PTR
3995 expression which must have pointer type, using Object Size type
3996 OSTYPE (only the least significant 2 bits are used).
3997 On success, sets PREF->REF to the DECL of the referenced object
3998 if it's unique, otherwise to null, PREF->OFFRNG to the range of
3999 offsets into it, and PREF->SIZRNG to the range of sizes of
4000 the object(s).
4001 VISITED is used to avoid visiting the same PHI operand multiple
4002 times, and, when nonnull, RVALS to determine range information.
4003 Returns true on success, false when the size cannot be determined.
4005 The function is intended for diagnostics and should not be used
4006 to influence code generation or optimization. */
4008 static bool
4011 {
4017 {
4018 /* Bail if the reference is to the pointer itself (as opposed
4019 to what it points to). */
4030 }
4035 {
4039 {
4040 /* For raw memory functions like memcpy bail if the size
4041 of the enclosing object cannot be determined. */
4047 /* Otherwise, use the size of the enclosing object and add
4048 the offset of the member to the offset computed so far. */
4056 }
4058 /* Bail if the reference is to the pointer itself (as opposed
4059 to what it points to). */
4064 /* Only return constant sizes for now while callers depend
4065 on it. INT0LEN is true for interior zero-length arrays. */
4069 {
4072 }
4079 }
4082 {
4087 /* Avoid arrays of pointers. FIXME: Hande pointers to arrays
4088 of known bound. */
4092 {
4093 /* Give up for MEM_REFs of vector types; those may be synthesized
4094 from multiple assignments to consecutive data members. See PR
4095 93200.
4096 FIXME: Deal with this more generally, e.g., by marking up such
4097 MEM_REFs at the time they're created. */
4101 }
4109 /* Fail unless the size of the object is zero. */
4113 {
4114 /* Convert the array index range determined above to a byte
4115 offset. */
4118 {
4119 /* Adjust the index by the low bound of the array domain
4120 (normally zero but 1 in Fortran). */
4124 }
4136 {
4137 /* Execpt for the permissive raw memory functions which
4138 use the size of the whole object determined above,
4139 use the size of the referenced array. */
4142 }
4143 }
4149 }
4152 {
4155 {
4156 /* If STMT is a call to an allocation function get the size
4157 from its argument(s). If successful, also set *PDECL to
4158 PTR for the caller to include in diagnostics. */
4161 {
4166 }
4168 }
4170 /* TODO: Handle PHI. */
4179 /* Avoid conversions from non-pointers. */
4183 {
4184 /* If the the offset in the expression can be determined use
4185 it to adjust the overall offset. Otherwise, set the overall
4186 offset to the maximum. */
4191 {
4194 }
4198 }
4203 }
4212 {
4215 }
4218 }
4220 /* Convenience wrapper around the above. */
4222 static tree
4225 {
4228 bool success
4238 {
4243 }
4249 }
4251 /* Transitional wrapper around the above. The function should be removed
4252 once callers transition to one of the two above. */
4254 tree
4257 {
4258 /* Set the initial offsets to zero and size to negative to indicate
4259 none has been computed yet. */
4260 access_ref ref;
4272 }
4274 /* Helper to determine and check the sizes of the source and the destination
4275 of calls to __builtin_{bzero,memcpy,mempcpy,memset} calls. EXP is the
4276 call expression, DEST is the destination argument, SRC is the source
4277 argument or null, and LEN is the number of bytes. Use Object Size type-0
4278 regardless of the OPT_Wstringop_overflow_ setting. Return true on success
4279 (no overflow or invalid sizes), false otherwise. */
4281 static bool
4283 {
4284 /* For functions like memset and memcpy that operate on raw memory
4285 try to determine the size of the largest source and destination
4286 object using type-0 Object Size regardless of the object size
4287 type specified by the option. */
4288 access_data data;
4294 }
4296 /* Validate memchr arguments without performing any expansion.
4297 Return NULL_RTX. */
4299 static rtx
4301 {
4309 /* Diagnose calls where the specified length exceeds the size
4310 of the object. */
4312 {
4313 access_data data;
4318 }
4321 }
4323 /* Expand a call EXP to the memcpy builtin.
4324 Return NULL_RTX if we failed, the caller should emit a normal call,
4325 otherwise try to get the result in TARGET, if convenient (and in
4326 mode MODE if that's convenient). */
4328 static rtx
4330 {
4343 }
4345 /* Check a call EXP to the memmove built-in for validity.
4346 Return NULL_RTX on both success and failure. */
4348 static rtx
4350 {
4363 }
4365 /* Expand a call EXP to the mempcpy builtin.
4366 Return NULL_RTX if we failed; the caller should emit a normal call,
4367 otherwise try to get the result in TARGET, if convenient (and in
4368 mode MODE if that's convenient). */
4370 static rtx
4372 {
4381 /* Policy does not generally allow using compute_objsize (which
4382 is used internally by check_memop_size) to change code generation
4383 or drive optimization decisions.
4385 In this instance it is safe because the code we generate has
4386 the same semantics regardless of the return value of
4387 check_memop_sizes. Exactly the same amount of data is copied
4388 and the return value is exactly the same in both cases.
4390 Furthermore, check_memop_size always uses mode 0 for the call to
4391 compute_objsize, so the imprecise nature of compute_objsize is
4392 avoided. */
4394 /* Avoid expanding mempcpy into memcpy when the call is determined
4395 to overflow the buffer. This also prevents the same overflow
4396 from being diagnosed again when expanding memcpy. */
4402 }
4404 /* Helper function to do the actual work for expand of memory copy family
4405 functions (memcpy, mempcpy, stpcpy). Expansing should assign LEN bytes
4406 of memory from SRC to DEST and assign to TARGET if convenient. Return
4407 value is based on RETMODE argument. */
4409 static rtx
4413 {
4426 /* If DEST is not a pointer type, call the normal function. */
4430 /* If either SRC is not a pointer type, don't do this
4431 operation in-line. */
4448 /* If SRC is a string constant and block move would be done by
4449 pieces, we can avoid loading the string from memory and only
4450 stored the computed constants. This works in the overlap
4451 (memmove) case as well because store_by_pieces just generates a
4452 series of stores of constants from the string constant returned
4453 by c_getstr(). */
4460 {
4462 builtin_memcpy_read_str,
4468 }
4473 /* Copy word part most expediently. */
4480 && !might_overlap
4489 /* Bail out when a mempcpy call would be expanded as libcall and when
4490 we have a target that provides a fast implementation
4491 of mempcpy routine. */
4499 {
4502 }
4505 {
4507 /* stpcpy pointer to last byte. */
4510 }
4513 }
4515 static rtx
4518 {
4521 }
4523 /* Expand into a movstr instruction, if one is available. Return NULL_RTX if
4524 we failed, the caller should emit a normal call, otherwise try to
4525 get the result in TARGET, if convenient.
4526 Return value is based on RETMODE argument. */
4528 static rtx
4530 {
4532 rtx dest_mem;
4533 rtx src_mem;
4541 {
4544 }
4554 {
4556 /* movstr is supposed to set end to the address of the NUL
4557 terminator. If the caller requested a mempcpy-like return value,
4558 adjust it. */
4560 {
4564 }
4565 }
4567 }
4569 /* Do some very basic size validation of a call to the strcpy builtin
4570 given by EXP. Return NULL_RTX to have the built-in expand to a call
4571 to the library function. */
4573 static rtx
4575 {
4583 /* Detect unterminated source (only). */
4587 /* There is no way here to determine the length of the string in
4588 the destination to which the SRC string is being appended so
4589 just diagnose cases when the souce string is longer than
4590 the destination object. */
4592 access_data data;
4599 }
4601 /* Expand expression EXP, which is a call to the strcpy builtin. Return
4602 NULL_RTX if we failed the caller should emit a normal call, otherwise
4603 try to get the result in TARGET, if convenient (and in mode MODE if that's
4604 convenient). */
4606 static rtx
4608 {
4616 {
4617 access_data data;
4622 }
4625 {
4626 /* Check to see if the argument was declared attribute nonstring
4627 and if so, issue a warning since at this point it's not known
4628 to be nul-terminated. */
4632 }
4635 }
4637 /* Helper function to do the actual work for expand_builtin_strcpy. The
4638 arguments to the builtin_strcpy call DEST and SRC are broken out
4639 so that this can also be called without constructing an actual CALL_EXPR.
4640 The other arguments and return value are the same as for
4641 expand_builtin_strcpy. */
4643 static rtx
4645 {
4646 /* Detect strcpy calls with unterminated arrays.. */
4648 {
4649 /* NONSTR refers to the non-nul terminated constant array. */
4653 }
4656 }
4658 /* Expand a call EXP to the stpcpy builtin.
4659 Return NULL_RTX if we failed the caller should emit a normal call,
4660 otherwise try to get the result in TARGET, if convenient (and in
4661 mode MODE if that's convenient). */
4663 static rtx
4665 {
4676 {
4677 access_data data;
4682 }
4684 /* If return value is ignored, transform stpcpy into strcpy. */
4686 {
4690 }
4691 else
4692 {
4694 rtx ret;
4696 /* Ensure we get an actual string whose length can be evaluated at
4697 compile-time, not an expression containing a string. This is
4698 because the latter will potentially produce pessimized code
4699 when used to produce the return value. */
4700 c_strlen_data lendata = { };
4718 {
4722 {
4726 {
4728 {
4731 else
4733 }
4742 }
4743 }
4744 }
4748 }
4749 }
4751 /* Expand a call EXP to the stpcpy builtin and diagnose uses of nonstring
4752 arguments while being careful to avoid duplicate warnings (which could
4753 be issued if the expander were to expand the call, resulting in it
4754 being emitted in expand_call(). */
4756 static rtx
4758 {
4760 {
4761 /* The call has been successfully expanded. Check for nonstring
4762 arguments and issue warnings as appropriate. */
4765 }
4768 }
4770 /* Check a call EXP to the stpncpy built-in for validity.
4771 Return NULL_RTX on both success and failure. */
4773 static rtx
4775 {
4781 /* The source and destination of the call. */
4785 /* The exact number of bytes to write (not the maximum). */
4790 access_data data;
4791 /* The size of the destination object. */
4798 }
4800 /* Callback routine for store_by_pieces. Read GET_MODE_BITSIZE (MODE)
4801 bytes from constant string DATA + OFFSET and return it as target
4802 constant. */
4804 rtx
4806 scalar_int_mode mode)
4807 {
4814 }
4816 /* Helper to check the sizes of sequences and the destination of calls
4817 to __builtin_strncat and __builtin___strncat_chk. Returns true on
4818 success (no overflow or invalid sizes), false otherwise. */
4820 static bool
4822 {
4827 /* Try to determine the range of lengths that the source expression
4828 refers to. */
4829 c_strlen_data lendata = { };
4832 /* Try to verify that the destination is big enough for the shortest
4833 string. */
4835 access_data data;
4837 {
4838 /* If it hasn't been provided by __strncat_chk, try to determine
4839 the size of the destination object into which the source is
4840 being copied. */
4842 }
4844 /* Add one for the terminating nul. */
4847 size_one_node)
4850 /* The strncat function copies at most MAXREAD bytes and always appends
4851 the terminating nul so the specified upper bound should never be equal
4852 to (or greater than) the size of the destination. */
4855 {
4864 }
4872 /* The number of bytes to write is LEN but check_access will alsoa
4873 check SRCLEN if LEN's value isn't known. */
4876 }
4878 /* Similar to expand_builtin_strcat, do some very basic size validation
4879 of a call to the strcpy builtin given by EXP. Return NULL_RTX to have
4880 the built-in expand to a call to the library function. */
4882 static rtx
4884 {
4892 /* The upper bound on the number of bytes to write. */
4895 /* Detect unterminated source (only). */
4899 /* The length of the source sequence. */
4902 /* Try to determine the range of lengths that the source expression
4903 refers to. Since the lengths are only used for warning and not
4904 for code generation disable strict mode below. */
4907 {
4908 c_strlen_data lendata = { };
4911 }
4913 access_data data;
4914 /* Try to verify that the destination is big enough for the shortest
4915 string. First try to determine the size of the destination object
4916 into which the source is being copied. */
4919 /* Add one for the terminating nul. */
4920 tree srclen = (maxlen
4922 size_one_node)
4925 /* The strncat function copies at most MAXREAD bytes and always appends
4926 the terminating nul so the specified upper bound should never be equal
4927 to (or greater than) the size of the destination. */
4930 {
4939 }
4951 }
4953 /* Expand expression EXP, which is a call to the strncpy builtin. Return
4954 NULL_RTX if we failed the caller should emit a normal call. */
4956 static rtx
4958 {
4966 /* The number of bytes to write (not the maximum). */
4972 /* The length of the source sequence. */
4976 {
4977 access_data data;
4981 /* The number of bytes to write is LEN but check_access will also
4982 check SLEN if LEN's value isn't known. */
4985 }
4987 /* We must be passed a constant len and src parameter. */
4993 /* We're required to pad with trailing zeros if the requested
4994 len is greater than strlen(s2)+1. In that case try to
4995 use store_by_pieces, if it fails, punt. */
4997 {
5000 rtx dest_mem;
5004 builtin_strncpy_read_str,
5011 builtin_strncpy_read_str,
5013 RETURN_BEGIN);
5017 }
5020 }
5022 /* Callback routine for store_by_pieces. Read GET_MODE_BITSIZE (MODE)
5023 bytes from constant string DATA + OFFSET and return it as target
5024 constant. */
5026 rtx
5028 scalar_int_mode mode)
5029 {
5036 }
5038 /* Callback routine for store_by_pieces. Return the RTL of a register
5039 containing GET_MODE_SIZE (MODE) consecutive copies of the unsigned
5040 char value given in the RTL register data. For example, if mode is
5041 4 bytes wide, return the RTL for 0x01010101*data. */
5043 static rtx
5045 scalar_int_mode mode)
5046 {
5062 }
5064 /* Expand expression EXP, which is a call to the memset builtin. Return
5065 NULL_RTX if we failed the caller should emit a normal call, otherwise
5066 try to get the result in TARGET, if convenient (and in mode MODE if that's
5067 convenient). */
5069 static rtx
5071 {
5083 }
5085 /* Helper function to do the actual work for expand_builtin_memset. The
5086 arguments to the builtin_memset call DEST, VAL, and LEN are broken out
5087 so that this can also be called without constructing an actual CALL_EXPR.
5088 The other arguments and return value are the same as for
5089 expand_builtin_memset. */
5091 static rtx
5094 {
5097 machine_mode val_mode;
5109 /* If DEST is not a pointer type, don't do this operation in-line. */
5120 /* If the LEN parameter is zero, return DEST. */
5122 {
5123 /* Evaluate and ignore VAL in case it has side-effects. */
5126 }
5128 /* Stabilize the arguments in case we fail. */
5140 {
5141 rtx val_rtx;
5146 /* Assume that we can memset by pieces if we can store
5147 * the coefficients by pieces (in the required modes).
5148 * We can't pass builtin_memset_gen_str as that emits RTL. */
5154 {
5159 }
5163 probable_max_size))
5169 }
5175 {
5182 RETURN_BEGIN);
5187 probable_max_size))
5193 }
5201 probable_max_size);
5204 {
5207 }
5211 do_libcall:
5220 else
5225 }
5227 /* Expand expression EXP, which is a call to the bzero builtin. Return
5228 NULL_RTX if we failed the caller should emit a normal call. */
5230 static rtx
5232 {
5241 /* New argument list transforming bzero(ptr x, int y) to
5242 memset(ptr x, int 0, size_t y). This is done this way
5243 so that if it isn't expanded inline, we fallback to
5244 calling bzero instead of memset. */
5252 }
5254 /* Try to expand cmpstr operation ICODE with the given operands.
5255 Return the result rtx on success, otherwise return null. */
5257 static rtx
5259 HOST_WIDE_INT align)
5260 {
5274 }
5276 /* Expand expression EXP, which is a call to the memcmp built-in function.
5277 Return NULL_RTX if we failed and the caller should emit a normal call,
5278 otherwise try to get the result in TARGET, if convenient.
5279 RESULT_EQ is true if we can relax the returned value to be either zero
5280 or nonzero, without caring about the sign. */
5282 static rtx
5284 {
5295 /* Diagnose calls where the specified length exceeds the size of either
5296 object. */
5297 access_data data;
5303 {
5304 access_data data;
5309 }
5311 /* If the specified length exceeds the size of either object,
5312 call the function. */
5316 /* Due to the performance benefit, always inline the calls first
5317 when result_eq is false. */
5321 {
5325 }
5333 /* If we don't have POINTER_TYPE, call the function. */
5341 /* Set MEM_SIZE as appropriate. */
5343 {
5346 }
5352 {
5356 }
5358 /* If SRC is a string constant and block move would be done
5359 by pieces, we can avoid loading the string from memory
5360 and only stored the computed constants. */
5372 {
5373 /* Return the value in the proper mode for this function. */
5378 {
5381 }
5384 }
5387 }
5389 /* Expand expression EXP, which is a call to the strcmp builtin. Return NULL_RTX
5390 if we failed the caller should emit a normal call, otherwise try to get
5391 the result in TARGET, if convenient. */
5393 static rtx
5395 {
5406 /* Due to the performance benefit, always inline the calls first. */
5420 /* If we don't have POINTER_TYPE, call the function. */
5424 /* Stabilize the arguments in case gen_cmpstr(n)si fail. */
5431 /* Try to call cmpstrsi. */
5436 /* Try to determine at least one length and call cmpstrnsi. */
5438 {
5439 tree len;
5440 rtx arg3_rtx;
5450 /* If we don't have a constant length for the first, use the length
5451 of the second, if we know it. We don't require a constant for
5452 this case; some cost analysis could be done if both are available
5453 but neither is constant. For now, assume they're equally cheap,
5454 unless one has side effects. If both strings have constant lengths,
5455 use the smaller. */
5471 else
5474 /* If both arguments have side effects, we cannot optimize. */
5476 {
5478 result = expand_cmpstrn_or_cmpmem
5481 }
5482 }
5486 {
5487 /* Check to see if the argument was declared attribute nonstring
5488 and if so, issue a warning since at this point it's not known
5489 to be nul-terminated. */
5492 /* Return the value in the proper mode for this function. */
5500 }
5502 /* Expand the library call ourselves using a stabilized argument
5503 list to avoid re-evaluating the function's arguments twice. */
5508 }
5510 /* Expand expression EXP, which is a call to the strncmp builtin. Return
5511 NULL_RTX if we failed the caller should emit a normal call, otherwise try to get
5512 the result in TARGET, if convenient. */
5514 static rtx
5516 ATTRIBUTE_UNUSED machine_mode mode)
5517 {
5530 /* Due to the performance benefit, always inline the calls first. */
5536 /* If c_strlen can determine an expression for one of the string
5537 lengths, and it doesn't have side effects, then emit cmpstrnsi
5538 using length MIN(strlen(string)+1, arg3). */
5543 tree len;
5560 /* If we don't have a constant length for the first, use the length
5561 of the second, if we know it. If neither string is constant length,
5562 use the given length argument. We don't require a constant for
5563 this case; some cost analysis could be done if both are available
5564 but neither is constant. For now, assume they're equally cheap,
5565 unless one has side effects. If both strings have constant lengths,
5566 use the smaller. */
5584 else
5587 /* If we are not using the given length, we must incorporate it here.
5588 The actual new length parameter will be MIN(len,arg3) in this case. */
5590 {
5593 }
5603 {
5604 /* Check to see if the argument was declared attribute nonstring
5605 and if so, issue a warning since at this point it's not known
5606 to be nul-terminated. */
5609 /* Return the value in the proper mode for this function. */
5617 }
5619 /* Expand the library call ourselves using a stabilized argument
5620 list to avoid re-evaluating the function's arguments twice. */
5625 }
5627 /* Expand a call to __builtin_saveregs, generating the result in TARGET,
5628 if that's convenient. */
5630 rtx
5632 {
5633 rtx val;
5636 /* Don't do __builtin_saveregs more than once in a function.
5637 Save the result of the first call and reuse it. */
5641 /* When this function is called, it means that registers must be
5642 saved on entry to this function. So we migrate the call to the
5643 first insn of this function. */
5647 /* Do whatever the machine needs done in this case. */
5655 /* Put the insns after the NOTE that starts the function. If this
5656 is inside a start_sequence, make the outer-level insn chain current, so
5657 the code is placed at the start of the function. */
5663 }
5665 /* Expand a call to __builtin_next_arg. */
5667 static rtx
5669 {
5670 /* Checking arguments is already done in fold_builtin_next_arg
5671 that must be called before this function. */
5676 }
5678 /* Make it easier for the backends by protecting the valist argument
5679 from multiple evaluations. */
5681 static tree
5683 {
5686 /* The current way of determining the type of valist is completely
5687 bogus. We should have the information on the va builtin instead. */
5692 {
5696 /* For this case, the backends will be expecting a pointer to
5697 vatype, but it's possible we've actually been given an array
5698 (an actual TARGET_CANONICAL_VA_LIST_TYPE (valist)).
5699 So fix it. */
5701 {
5704 }
5705 }
5706 else
5707 {
5711 {
5717 }
5723 }
5726 }
5728 /* The "standard" definition of va_list is void*. */
5730 tree
5732 {
5734 }
5736 /* The "standard" abi va_list is va_list_type_node. */
5738 tree
5740 {
5742 }
5744 /* The "standard" type of va_list is va_list_type_node. */
5746 tree
5748 {
5755 {
5756 /* If va_list is an array type, the argument may have decayed
5757 to a pointer type, e.g. by being passed to another function.
5758 In that case, unwrap both types so that we can compare the
5759 underlying records. */
5762 {
5765 }
5766 }
5771 }
5773 /* The "standard" implementation of va_start: just assign `nextarg' to
5774 the variable. */
5776 void
5778 {
5781 }
5783 /* Expand EXP, a call to __builtin_va_start. */
5785 static rtx
5787 {
5788 rtx nextarg;
5789 tree valist;
5793 {
5796 }
5806 else
5810 }
5812 /* Expand EXP, a call to __builtin_va_end. */
5814 static rtx
5816 {
5819 /* Evaluate for side effects, if needed. I hate macros that don't
5820 do that. */
5825 }
5827 /* Expand EXP, a call to __builtin_va_copy. We do this as a
5828 builtin rather than just as an assignment in stdarg.h because of the
5829 nastiness of array-type va_list types. */
5831 static rtx
5833 {
5846 {
5850 }
5851 else
5852 {
5855 /* Evaluate to pointers. */
5864 /* "Dereference" to BLKmode memories. */
5872 /* Copy. */
5874 }
5877 }
5879 /* Expand a call to one of the builtin functions __builtin_frame_address or
5880 __builtin_return_address. */
5882 static rtx
5884 {
5885 /* The argument must be a nonnegative integer constant.
5886 It counts the number of frames to scan up the stack.
5887 The value is either the frame pointer value or the return
5888 address saved in that frame. */
5890 /* Warning about missing arg was already issued. */
5893 {
5896 }
5897 else
5898 {
5899 /* Number of frames to scan up the stack. */
5904 /* Some ports cannot access arbitrary stack frames. */
5906 {
5909 }
5912 {
5913 /* Warn since no effort is made to ensure that any frame
5914 beyond the current one exists or can be safely reached. */
5917 }
5919 /* For __builtin_frame_address, return what we've got. */
5927 }
5928 }
5930 /* Expand EXP, a call to the alloca builtin. Return NULL_RTX if we
5931 failed and the caller should emit a normal call. */
5933 static rtx
5935 {
5936 rtx op0;
5937 rtx result;
5940 HOST_WIDE_INT max_size;
5943 bool valid_arglist
5946 VOID_TYPE)
5957 || (!alloca_for_var
5960 ))
5961 {
5962 /* -Walloca-larger-than and -Wvla-larger-than settings of
5963 less than HOST_WIDE_INT_MAX override the more general
5964 -Walloc-size-larger-than so unless either of the former
5965 options is smaller than the last one (wchich would imply
5966 that the call was already checked), check the alloca
5967 arguments for overflow. */
5971 }
5973 /* Compute the argument. */
5976 /* Compute the alignment. */
5978 ? BIGGEST_ALIGNMENT
5981 /* Compute the maximum size. */
5986 /* Allocate the desired space. If the allocation stems from the declaration
5987 of a variable-sized object, it cannot accumulate. */
5988 result
5992 /* Dynamic allocations for variables are recorded during gimplification. */
5997 }
5999 /* Emit a call to __asan_allocas_unpoison call in EXP. Add to second argument
6000 of the call virtual_stack_dynamic_rtx - stack_pointer_rtx, which is the
6001 STACK_DYNAMIC_OFFSET value. See motivation for this in comment to
6002 handle_builtin_stack_restore function. */
6004 static rtx
6006 {
6013 OPTAB_LIB_WIDEN);
6016 OPTAB_LIB_WIDEN);
6021 }
6023 /* Expand a call to bswap builtin in EXP.
6024 Return NULL_RTX if a normal call should be emitted rather than expanding the
6025 function in-line. If convenient, the result should be placed in TARGET.
6026 SUBTARGET may be used as the target for computing one of EXP's operands. */
6028 static rtx
6030 rtx subtarget)
6031 {
6032 tree arg;
6033 rtx op0;
6051 }
6053 /* Expand a call to a unary builtin in EXP.
6054 Return NULL_RTX if a normal call should be emitted rather than expanding the
6055 function in-line. If convenient, the result should be placed in TARGET.
6056 SUBTARGET may be used as the target for computing one of EXP's operands. */
6058 static rtx
6061 {
6062 rtx op0;
6067 /* Compute the argument. */
6069 (subtarget
6073 /* Compute op, into TARGET if possible.
6074 Set TARGET to wherever the result comes back. */
6080 }
6082 /* Expand a call to __builtin_expect. We just return our argument
6083 as the builtin_expect semantic should've been already executed by
6084 tree branch prediction pass. */
6086 static rtx
6088 {
6089 tree arg;
6096 /* When guessing was done, the hints should be already stripped away. */
6100 }
6102 /* Expand a call to __builtin_expect_with_probability. We just return our
6103 argument as the builtin_expect semantic should've been already executed by
6104 tree branch prediction pass. */
6106 static rtx
6108 {
6109 tree arg;
6116 /* When guessing was done, the hints should be already stripped away. */
6120 }
6123 /* Expand a call to __builtin_assume_aligned. We just return our first
6124 argument as the builtin_assume_aligned semantic should've been already
6125 executed by CCP. */
6127 static rtx
6129 {
6133 EXPAND_NORMAL);
6138 }
6140 void
6142 {
6144 {
6146 /* For trap insns when not accumulating outgoing args force
6147 REG_ARGS_SIZE note to prevent crossjumping of calls with
6148 different args sizes. */
6151 }
6152 else
6153 {
6157 }
6160 }
6162 /* Expand a call to __builtin_unreachable. We do nothing except emit
6163 a barrier saying that control flow will not pass here.
6165 It is the responsibility of the program being compiled to ensure
6166 that control flow does never reach __builtin_unreachable. */
6167 static void
6169 {
6171 }
6173 /* Expand EXP, a call to fabs, fabsf or fabsl.
6174 Return NULL_RTX if a normal call should be emitted rather than expanding
6175 the function inline. If convenient, the result should be placed
6176 in TARGET. SUBTARGET may be used as the target for computing
6177 the operand. */
6179 static rtx
6181 {
6182 machine_mode mode;
6183 tree arg;
6184 rtx op0;
6194 }
6196 /* Expand EXP, a call to copysign, copysignf, or copysignl.
6197 Return NULL is a normal call should be emitted rather than expanding the
6198 function inline. If convenient, the result should be placed in TARGET.
6199 SUBTARGET may be used as the target for computing the operand. */
6201 static rtx
6203 {
6205 tree arg;
6217 }
6219 /* Expand a call to __builtin___clear_cache. */
6221 static rtx
6223 {
6225 {
6226 #ifdef CLEAR_INSN_CACHE
6227 /* There is no "clear_cache" insn, and __clear_cache() in libgcc
6228 does something. Just do the default expansion to a call to
6229 __clear_cache(). */
6231 #else
6232 /* There is no "clear_cache" insn, and __clear_cache() in libgcc
6233 does nothing. There is no need to call it. Do nothing. */
6236 }
6238 /* We have a "clear_cache" insn, and it will handle everything. */
6242 /* We must not expand to a library call. If we did, any
6243 fallback library function in libgcc that might contain a call to
6244 __builtin___clear_cache() would recurse infinitely. */
6246 {
6249 }
6252 {
6265 }
6267 }
6269 /* Given a trampoline address, make sure it satisfies TRAMPOLINE_ALIGNMENT. */
6271 static rtx
6273 {
6276 /* If we don't need too much alignment, we'll have been guaranteed
6277 proper alignment by get_trampoline_type. */
6281 /* Round address up to desired boundary. */
6292 }
6294 static rtx
6296 {
6312 /* If ONSTACK, the TRAMP argument should be the address of a field
6313 within the local function's FRAME decl. Either way, let's see if
6314 we can fill in the MEM_ATTRs for this memory. */
6318 /* Creator of a heap trampoline is responsible for making sure the
6319 address is aligned to at least STACK_BOUNDARY. Normally malloc
6320 will ensure this anyhow. */
6323 {
6327 }
6329 /* The FUNC argument should be the address of the nested function.
6330 Extract the actual function decl to pass to the hook. */
6337 /* Generate insns to initialize the trampoline. */
6341 {
6347 }
6350 }
6352 static rtx
6354 {
6355 rtx tramp;
6366 }
6368 /* Expand a call to the builtin descriptor initialization routine.
6369 A descriptor is made up of a couple of pointers to the static
6370 chain and the code entry in this order. */
6372 static rtx
6374 {
6379 VOID_TYPE))
6394 /* Generate insns to initialize the descriptor. */
6400 }
6402 /* Expand a call to the builtin descriptor adjustment routine. */
6404 static rtx
6406 {
6407 rtx tramp;
6414 /* Unalign the descriptor to allow runtime identification. */
6419 }
6421 /* Expand the call EXP to the built-in signbit, signbitf or signbitl
6422 function. The function first checks whether the back end provides
6423 an insn to implement signbit for the respective mode. If not, it
6424 checks whether the floating point format of the value is such that
6425 the sign bit can be extracted. If that is not the case, error out.
6426 EXP is the expression that is a call to the builtin function; if
6427 convenient, the result should be placed in TARGET. */
6428 static rtx
6430 {
6432 scalar_float_mode fmode;
6434 tree arg;
6437 rtx temp;
6450 /* Expand the argument yielding a RTX expression. */
6453 /* Check if the back end provides an insn that handles signbit for the
6454 argument's mode. */
6457 {
6463 }
6465 /* For floating point formats without a sign bit, implement signbit
6466 as "ARG < 0.0". */
6469 {
6470 /* But we can't do this if the format supports signed zero. */
6476 }
6479 {
6482 }
6483 else
6484 {
6486 /* Handle targets with different FP word orders. */
6489 else
6493 }
6495 /* Force the intermediate word_mode (or narrower) result into a
6496 register. This avoids attempting to create paradoxical SUBREGs
6497 of floating point modes below. */
6500 /* If the bitpos is within the "result mode" lowpart, the operation
6501 can be implement with a single bitwise AND. Otherwise, we need
6502 a right shift and an AND. */
6505 {
6513 }
6514 else
6515 {
6516 /* Perform a logical right shift to place the signbit in the least
6517 significant bit, then truncate the result to the desired mode
6518 and mask just this bit. */
6523 }
6526 }
6528 /* Expand fork or exec calls. TARGET is the desired target of the
6529 call. EXP is the call. FN is the
6530 identificator of the actual function. IGNORE is nonzero if the
6531 value is to be ignored. */
6533 static rtx
6535 {
6537 tree call;
6540 {
6541 /* Detect unterminated path. */
6545 /* Also detect unterminated first argument. */
6547 {
6555 }
6556 }
6559 /* If we are not profiling, just call the function. */
6563 /* Otherwise call the wrapper. This should be equivalent for the rest of
6564 compiler, so the code does not diverge, and the wrapper may run the
6565 code necessary for keeping the profiling sane. */
6568 {
6599 }
6611 }
6614 \f
6615 /* Reconstitute a mode for a __sync intrinsic operation. Since the type of
6616 the pointer in these functions is void*, the tree optimizers may remove
6617 casts. The mode computed in expand_builtin isn't reliable either, due
6618 to __sync_bool_compare_and_swap.
6620 FCODE_DIFF should be fcode - base, where base is the FOO_1 code for the
6621 group of builtins. This gives us log2 of the mode size. */
6625 {
6626 /* The size is not negotiable, so ask not to get BLKmode in return
6627 if the target indicates that a smaller size would be better. */
6629 }
6631 /* Expand the memory expression LOC and return the appropriate memory operand
6632 for the builtin_sync operations. */
6634 static rtx
6636 {
6646 /* Note that we explicitly do not want any alias information for this
6647 memory, so that we kill all other live memories. Otherwise we don't
6648 satisfy the full barrier semantics of the intrinsic. */
6655 /* The alignment needs to be at least according to that of the mode. */
6662 }
6664 /* Make sure an argument is in the right mode.
6665 EXP is the tree argument.
6666 MODE is the mode it should be in. */
6668 static rtx
6670 {
6671 rtx val;
6672 machine_mode old_mode;
6675 /* If VAL is promoted to a wider mode, convert it back to MODE. Take care
6676 of CONST_INTs, where we know the old_mode only from the call argument. */
6683 }
6686 /* Expand the __sync_xxx_and_fetch and __sync_fetch_and_xxx intrinsics.
6687 EXP is the CALL_EXPR. CODE is the rtx code
6688 that corresponds to the arithmetic or logical operation from the name;
6689 an exception here is that NOT actually means NAND. TARGET is an optional
6690 place for us to store the results; AFTER is true if this is the
6691 fetch_and_xxx form. */
6693 static rtx
6696 rtx target)
6697 {
6702 {
6709 {
6738 }
6739 }
6741 /* Expand the operands. */
6746 after);
6747 }
6749 /* Expand the __sync_val_compare_and_swap and __sync_bool_compare_and_swap
6750 intrinsics. EXP is the CALL_EXPR. IS_BOOL is
6751 true if this is the boolean form. TARGET is a place for us to store the
6752 results; this is NOT optional if IS_BOOL is true. */
6754 static rtx
6757 {
6761 /* Expand the operands. */
6768 {
6771 else
6773 }
6776 MEMMODEL_SYNC_SEQ_CST))
6780 }
6782 /* Expand the __sync_lock_test_and_set intrinsic. Note that the most
6783 general form is actually an atomic exchange, and some targets only
6784 support a reduced form with the second argument being a constant 1.
6785 EXP is the CALL_EXPR; TARGET is an optional place for us to store
6786 the results. */
6788 static rtx
6790 rtx target)
6791 {
6794 /* Expand the operands. */
6799 }
6801 /* Expand the __sync_lock_release intrinsic. EXP is the CALL_EXPR. */
6803 static void
6805 {
6806 rtx mem;
6808 /* Expand the operands. */
6812 }
6814 /* Given an integer representing an ``enum memmodel'', verify its
6815 correctness and return the memory model enum. */
6817 static enum memmodel
6819 {
6820 rtx op;
6822 location_t loc
6825 /* If the parameter is not a constant, it's a run time value so we'll just
6826 convert it to MEMMODEL_SEQ_CST to avoid annoying runtime checking. */
6836 {
6840 }
6842 /* Should never see a user explicit SYNC memodel model, so >= LAST works. */
6844 {
6848 }
6850 /* Workaround for Bugzilla 59448. GCC doesn't track consume properly, so
6851 be conservative and promote consume to acquire. */
6856 }
6858 /* Expand the __atomic_exchange intrinsic:
6859 TYPE __atomic_exchange (TYPE *object, TYPE desired, enum memmodel)
6860 EXP is the CALL_EXPR.
6861 TARGET is an optional place for us to store the results. */
6863 static rtx
6865 {
6874 /* Expand the operands. */
6879 }
6881 /* Expand the __atomic_compare_exchange intrinsic:
6882 bool __atomic_compare_exchange (TYPE *object, TYPE *expect,
6883 TYPE desired, BOOL weak,
6884 enum memmodel success,
6885 enum memmodel failure)
6886 EXP is the CALL_EXPR.
6887 TARGET is an optional place for us to store the results. */
6889 static rtx
6891 rtx target)
6892 {
6896 tree weak;
6898 location_t loc
6905 {
6907 "failure memory model cannot be stronger than success "
6910 }
6913 {
6915 "invalid failure memory model for "
6919 }
6925 /* Expand the operands. */
6941 /* Lest the rtl backend create a race condition with an imporoper store
6942 to memory, always create a new pseudo for OLDVAL. */
6949 /* Conditionally store back to EXPECT, lest we create a race condition
6950 with an improper store to memory. */
6951 /* ??? With a rearrangement of atomics at the gimple level, we can handle
6952 the normal case where EXPECT is totally private, i.e. a register. At
6953 which point the store can be unconditional. */
6961 }
6963 /* Helper function for expand_ifn_atomic_compare_exchange - expand
6964 internal ATOMIC_COMPARE_EXCHANGE call into __atomic_compare_exchange_N
6965 call. The weak parameter must be dropped to match the expected parameter
6966 list and the expected argument changed from value to pointer to memory
6967 slot. */
6969 static void
6971 {
6987 /* Skip the boolean weak parameter. */
6990 /* At present we only have BUILT_IN_ATOMIC_COMPARE_EXCHANGE_{1,2,4,8,16}. */
6993 built_in_function fncode
6998 fndecl);
7003 {
7010 }
7011 }
7013 /* Expand IFN_ATOMIC_COMPARE_EXCHANGE internal function. */
7015 void
7017 {
7023 tree lhs;
7025 location_t loc
7032 {
7034 "failure memory model cannot be stronger than success "
7037 }
7040 {
7042 "invalid failure memory model for "
7046 }
7049 {
7052 }
7054 /* Expand the operands. */
7067 {
7070 }
7074 {
7080 }
7081 }
7083 /* Expand the __atomic_load intrinsic:
7084 TYPE __atomic_load (TYPE *object, enum memmodel)
7085 EXP is the CALL_EXPR.
7086 TARGET is an optional place for us to store the results. */
7088 static rtx
7090 {
7091 rtx mem;
7096 {
7097 location_t loc
7102 }
7107 /* Expand the operand. */
7111 }
7114 /* Expand the __atomic_store intrinsic:
7115 void __atomic_store (TYPE *object, TYPE desired, enum memmodel)
7116 EXP is the CALL_EXPR.
7117 TARGET is an optional place for us to store the results. */
7119 static rtx
7121 {
7128 {
7129 location_t loc
7134 }
7139 /* Expand the operands. */
7144 }
7146 /* Expand the __atomic_fetch_XXX intrinsic:
7147 TYPE __atomic_fetch_XXX (TYPE *object, TYPE val, enum memmodel)
7148 EXP is the CALL_EXPR.
7149 TARGET is an optional place for us to store the results.
7150 CODE is the operation, PLUS, MINUS, ADD, XOR, or IOR.
7151 FETCH_AFTER is true if returning the result of the operation.
7152 FETCH_AFTER is false if returning the value before the operation.
7153 IGNORE is true if the result is not used.
7154 EXT_CALL is the correct builtin for an external call if this cannot be
7155 resolved to an instruction sequence. */
7157 static rtx
7161 {
7164 tree fndecl;
7165 tree addr;
7169 /* Expand the operands. */
7173 /* Only try generating instructions if inlining is turned on. */
7175 {
7179 }
7181 /* Return if a different routine isn't needed for the library call. */
7185 /* Change the call to the specified function. */
7193 /* If we will emit code after the call, the call cannot be a tail call.
7194 If it is emitted as a tail call, a barrier is emitted after it, and
7195 then all trailing code is removed. */
7199 /* Expand the call here so we can emit trailing code. */
7202 /* Replace the original function just in case it matters. */
7205 /* Then issue the arithmetic correction to return the right result. */
7207 {
7209 {
7211 OPTAB_LIB_WIDEN);
7213 }
7214 else
7216 OPTAB_LIB_WIDEN);
7217 }
7219 }
7221 /* Expand IFN_ATOMIC_BIT_TEST_AND_* internal function. */
7223 void
7225 {
7233 optab optab;
7245 {
7260 }
7263 {
7270 }
7292 {
7297 }
7298 else
7300 OPTAB_DIRECT);
7303 }
7305 /* Expand an atomic clear operation.
7306 void _atomic_clear (BOOL *obj, enum memmodel)
7307 EXP is the call expression. */
7309 static rtx
7311 {
7312 machine_mode mode;
7321 {
7322 location_t loc
7327 }
7329 /* Try issuing an __atomic_store, and allow fallback to __sync_lock_release.
7330 Failing that, a store is issued by __atomic_store. The only way this can
7331 fail is if the bool type is larger than a word size. Unlikely, but
7332 handle it anyway for completeness. Assume a single threaded model since
7333 there is no atomic support in this case, and no barriers are required. */
7338 }
7340 /* Expand an atomic test_and_set operation.
7341 bool _atomic_test_and_set (BOOL *obj, enum memmodel)
7342 EXP is the call expression. */
7344 static rtx
7346 {
7347 rtx mem;
7349 machine_mode mode;
7356 }
7359 /* Return true if (optional) argument ARG1 of size ARG0 is always lock free on
7360 this architecture. If ARG1 is NULL, use typical alignment for size ARG0. */
7362 static tree
7364 {
7366 machine_mode mode;
7372 /* We need a corresponding integer mode for the access to be lock-free. */
7380 {
7383 /* Either this argument is null, or it's a fake pointer encoding
7384 the alignment of the object. */
7390 else
7392 }
7393 else
7394 {
7397 /* This function is usually invoked and folded immediately by the front
7398 end before anything else has a chance to look at it. The pointer
7399 parameter at this point is usually cast to a void *, so check for that
7400 and look past the cast. */
7410 /* Get the underlying type of the object. */
7413 }
7415 /* If the object has smaller alignment, the lock free routines cannot
7416 be used. */
7420 /* Check if a compare_and_swap pattern exists for the mode which represents
7421 the required size. The pattern is not allowed to fail, so the existence
7422 of the pattern indicates support is present. Also require that an
7423 atomic load exists for the required size. */
7426 else
7428 }
7430 /* Return true if the parameters to call EXP represent an object which will
7431 always generate lock free instructions. The first argument represents the
7432 size of the object, and the second parameter is a pointer to the object
7433 itself. If NULL is passed for the object, then the result is based on
7434 typical alignment for an object of the specified size. Otherwise return
7435 false. */
7437 static rtx
7439 {
7440 tree size;
7445 {
7448 }
7454 }
7456 /* Return a one or zero if it can be determined that object ARG1 of size ARG
7457 is lock free on this architecture. */
7459 static tree
7461 {
7465 /* If it isn't always lock free, don't generate a result. */
7470 }
7472 /* Return true if the parameters to call EXP represent an object which will
7473 always generate lock free instructions. The first argument represents the
7474 size of the object, and the second parameter is a pointer to the object
7475 itself. If NULL is passed for the object, then the result is based on
7476 typical alignment for an object of the specified size. Otherwise return
7477 NULL*/
7479 static rtx
7481 {
7482 tree size;
7487 {
7490 }
7495 /* If the value is known at compile time, return the RTX for it. */
7501 }
7503 /* Expand the __atomic_thread_fence intrinsic:
7504 void __atomic_thread_fence (enum memmodel)
7505 EXP is the CALL_EXPR. */
7507 static void
7509 {
7512 }
7514 /* Expand the __atomic_signal_fence intrinsic:
7515 void __atomic_signal_fence (enum memmodel)
7516 EXP is the CALL_EXPR. */
7518 static void
7520 {
7523 }
7525 /* Expand the __sync_synchronize intrinsic. */
7527 static void
7529 {
7531 }
7533 static rtx
7535 {
7541 {
7543 /* If the target is not sutitable then create a new target. */
7551 }
7554 }
7556 static void
7558 {
7564 {
7571 }
7573 }
7575 \f
7576 /* Emit code to restore the current value of stack. */
7578 static void
7580 {
7592 }
7594 /* Emit code to save the current value of stack. */
7596 static rtx
7598 {
7603 }
7605 /* Emit code to get the openacc gang, worker or vector id or size. */
7607 static rtx
7609 {
7611 rtx fallback_retval;
7614 {
7627 }
7630 {
7633 }
7637 {
7640 }
7644 {
7652 }
7661 {
7664 }
7672 }
7674 /* Expand a string compare operation using a sequence of char comparison
7675 to get rid of the calling overhead, with result going to TARGET if
7676 that's convenient.
7678 VAR_STR is the variable string source;
7679 CONST_STR is the constant string source;
7680 LENGTH is the number of chars to compare;
7681 CONST_STR_N indicates which source string is the constant string;
7682 IS_MEMCMP indicates whether it's a memcmp or strcmp.
7684 to: (assume const_str_n is 2, i.e., arg2 is a constant string)
7686 target = (int) (unsigned char) var_str[0]
7687 - (int) (unsigned char) const_str[0];
7688 if (target != 0)
7689 goto ne_label;
7690 ...
7691 target = (int) (unsigned char) var_str[length - 2]
7692 - (int) (unsigned char) const_str[length - 2];
7693 if (target != 0)
7694 goto ne_label;
7695 target = (int) (unsigned char) var_str[length - 1]
7696 - (int) (unsigned char) const_str[length - 1];
7697 ne_label:
7698 */
7700 static rtx
7704 {
7706 rtx var_rtx_array
7713 scalar_int_mode unit_mode
7719 {
7720 var_rtx
7734 }
7742 }
7744 /* Inline expansion a call to str(n)cmp, with result going to
7745 TARGET if that's convenient.
7746 If the call is not been inlined, return NULL_RTX. */
7747 static rtx
7749 {
7755 /* Do NOT apply this inlining expansion when optimizing for size or
7756 optimization level below 2. */
7764 /* On a target where the type of the call (int) has same or narrower presicion
7765 than unsigned char, give up the inlining expansion. */
7781 /* If neither strings is constant string, the call is not qualify. */
7785 /* For strncmp, if the length is not a const, not qualify. */
7787 {
7790 else
7792 }
7807 else
7816 /* If the length of the comparision is larger than the threshold,
7817 do nothing. */
7819 param_builtin_string_cmp_inline_length)
7824 /* Now, start inline expansion the call. */
7828 }
7830 /* Expand a call to __builtin_speculation_safe_value_<N>. MODE
7831 represents the size of the first argument to that call, or VOIDmode
7832 if the argument is a pointer. IGNORE will be true if the result
7833 isn't used. */
7834 static rtx
7837 {
7844 {
7847 }
7851 /* An optional second argument can be used as a failsafe value on
7852 some machines. If it isn't present, then the failsafe value is
7853 assumed to be 0. */
7855 {
7858 }
7859 else
7862 /* If the result isn't used, the behavior is undefined. It would be
7863 nice to emit a warning here, but path splitting means this might
7864 happen with legitimate code. So simply drop the builtin
7865 expansion in that case; we've handled any side-effects above. */
7869 /* If we don't have a suitable target, create one to hold the result. */
7877 }
7879 /* Expand an expression EXP that calls a built-in function,
7880 with result going to TARGET if that's convenient
7881 (and in mode MODE if that's convenient).
7882 SUBTARGET may be used as the target for computing one of EXP's operands.
7883 IGNORE is nonzero if the value is to be ignored. */
7885 rtx
7888 {
7896 /* When ASan is enabled, we don't want to expand some memory/string
7897 builtins and rely on libsanitizer's hooks. This allows us to avoid
7898 redundant checks and be sure, that possible overflow will be detected
7899 by ASan. */
7905 /* When not optimizing, generate calls to library functions for a certain
7906 set of builtins. */
7920 /* The built-in function expanders test for target == const0_rtx
7921 to determine whether the function's result will be ignored. */
7925 /* If the result of a pure or const built-in function is ignored, and
7926 none of its arguments are volatile, we can avoid expanding the
7927 built-in call and just evaluate the arguments for side-effects. */
7931 {
7933 tree arg;
7934 call_expr_arg_iterator iter;
7938 {
7941 }
7944 {
7948 }
7949 }
7952 {
7970 /* Just do a normal library call if we were unable to fold
7971 the values. */
8048 /* __builtin_apply (FUNCTION, ARGUMENTS, ARGSIZE) invokes
8049 FUNCTION with a copy of the parameters described by
8050 ARGUMENTS, and ARGSIZE. It returns a block of memory
8051 allocated on the stack into which is stored all the registers
8052 that might possibly be used for returning the result of a
8053 function. ARGUMENTS is the value returned by
8054 __builtin_apply_args. ARGSIZE is the number of bytes of
8055 arguments that must be copied. ??? How should this value be
8056 computed? We'll also need a safe worst case value for varargs
8057 functions. */
8064 else
8065 {
8073 }
8075 /* __builtin_return (RESULT) causes the function to return the
8076 value described by RESULT. RESULT is address of the block of
8077 memory returned by __builtin_apply. */
8087 /* All valid uses of __builtin_va_arg_pack () are removed during
8088 inlining. */
8093 /* All valid uses of __builtin_va_arg_pack_len () are removed during
8094 inlining. */
8098 /* Return the address of the first anonymous stack arg. */
8120 /* Returns the address of the area where the structure is returned.
8121 0 otherwise. */
8127 else
8130 CASE_BUILT_IN_ALLOCA:
8247 {
8250 }
8319 /* Expand it as BUILT_IN_MEMCMP_EQ first. If not successful, change it
8320 back to a BUILT_IN_STRCMP. Remember to delete the 3rd paramater
8321 when changing it to a strcmp call. */
8327 /* Change this call back to a BUILT_IN_STRCMP. */
8331 /* Delete the last parameter. */
8338 /* FALLTHROUGH */
8346 /* Expand it as BUILT_IN_MEMCMP_EQ first. If not successful, change it
8347 back to a BUILT_IN_STRNCMP. */
8353 /* Change it back to a BUILT_IN_STRNCMP. */
8356 /* FALLTHROUGH */
8371 {
8374 }
8378 /* This should have been lowered to the builtins below. */
8382 /* __builtin_setjmp_setup is passed a pointer to an array of five words
8383 and the receiver label. */
8385 {
8391 /* This is copied from the handling of non-local gotos. */
8393 nonlocal_goto_handler_labels
8395 nonlocal_goto_handler_labels);
8396 /* ??? Do not let expand_label treat us as such since we would
8397 not want to be both on the list of non-local labels and on
8398 the list of forced labels. */
8401 }
8405 /* __builtin_setjmp_receiver is passed the receiver label. */
8407 {
8413 }
8416 /* __builtin_longjmp is passed a pointer to an array of five words.
8417 It's similar to the C library longjmp function but works with
8418 __builtin_setjmp above. */
8421 {
8427 {
8430 }
8434 }
8443 /* This updates the setjmp buffer that is its argument with the value
8444 of the current stack pointer. */
8447 {
8448 rtx buf_addr
8453 }
8473 /* Various hooks for the DWARF 2 __throw routine. */
8479 #ifdef DWARF2_UNWIND_INFO
8485 #endif
8687 mode = get_builtin_sync_mode
8699 mode = get_builtin_sync_mode
8746 {
8750 mode =
8756 /* If this is turned into an external library call, the weak parameter
8757 must be dropped to match the expected parameter list. */
8762 /* Skip the boolean weak parameter. */
8767 }
8796 {
8806 }
8812 {
8822 }
8828 {
8838 }
8844 {
8854 }
8860 {
8870 }
8876 {
8886 }
9023 /* Do library call, if we failed to expand the builtin when
9024 folding. */
9044 }
9046 /* The switch statement above can drop through to cause the function
9047 to be called normally. */
9049 }
9051 /* Determine whether a tree node represents a call to a built-in
9052 function. If the tree T is a call to a built-in function with
9053 the right number of arguments of the appropriate types, return
9054 the DECL_FUNCTION_CODE of the call, e.g. BUILT_IN_SQRT.
9055 Otherwise the return value is END_BUILTINS. */
9057 enum built_in_function
9059 {
9062 const_call_expr_arg_iterator iter;
9074 {
9075 /* If a function doesn't take a variable number of arguments,
9076 the last element in the list will have type `void'. */
9079 {
9083 }
9092 {
9095 }
9097 {
9100 }
9102 {
9105 }
9107 {
9110 }
9111 else
9113 }
9115 /* Variable-length argument list. */
9117 }
9119 /* Fold a call to __builtin_constant_p, if we know its argument ARG will
9120 evaluate to a constant. */
9122 static tree
9124 {
9125 /* We return 1 for a numeric type that's known to be a constant
9126 value at compile-time or for an aggregate type that's a
9127 literal constant. */
9130 /* If we know this is a constant, emit the constant of one. */
9136 {
9143 }
9145 /* If this expression has side effects, show we don't know it to be a
9146 constant. Likewise if it's a pointer or aggregate type since in
9147 those case we only want literals, since those are only optimized
9148 when generating RTL, not later.
9149 And finally, if we are compiling an initializer, not code, we
9150 need to return a definite result now; there's not going to be any
9151 more optimization done. */
9156 || folding_initializer
9161 }
9163 /* Create builtin_expect or builtin_expect_with_probability
9164 with PRED and EXPECTED as its arguments and return it as a truthvalue.
9165 Fortran FE can also produce builtin_expect with PREDICTOR as third argument.
9166 builtin_expect_with_probability instead uses third argument as PROBABILITY
9167 value. */
9169 static tree
9172 {
9187 else
9189 predictor);
9193 }
9195 /* Fold a call to builtin_expect with arguments ARG0, ARG1, ARG2, ARG3. Return
9196 NULL_TREE if no simplification is possible. */
9198 tree
9200 tree arg3)
9201 {
9205 /* Distribute the expected value over short-circuiting operators.
9206 See through the cast from truthvalue_type_node to long. */
9213 /* If this is a builtin_expect within a builtin_expect keep the
9214 inner one. See through a comparison against a constant. It
9215 might have been added to create a thruthvalue. */
9231 {
9241 }
9243 /* If the argument isn't invariant then there's nothing else we can do. */
9247 /* If we expect that a comparison against the argument will fold to
9248 a constant return the constant. In practice, this means a true
9249 constant or the address of a non-weak symbol. */
9253 {
9254 do
9255 {
9257 }
9262 }
9264 /* Otherwise, ARG0 already has the proper type for the return value. */
9266 }
9268 /* Fold a call to __builtin_classify_type with argument ARG. */
9270 static tree
9272 {
9277 }
9279 /* Fold a call to __builtin_strlen with argument ARG. */
9281 static tree
9283 {
9286 else
9287 {
9288 c_strlen_data lendata = { };
9298 {
9304 }
9307 }
9308 }
9310 /* Fold a call to __builtin_inf or __builtin_huge_val. */
9312 static tree
9314 {
9315 REAL_VALUE_TYPE real;
9317 /* __builtin_inff is intended to be usable to define INFINITY on all
9318 targets. If an infinity is not available, INFINITY expands "to a
9319 positive constant of type float that overflows at translation
9320 time", footnote "In this case, using INFINITY will violate the
9321 constraint in 6.4.4 and thus require a diagnostic." (C99 7.12#4).
9322 Thus we pedwarn to ensure this constraint violation is
9323 diagnosed. */
9329 }
9331 /* Fold function call to builtin sincos, sincosf, or sincosl. Return
9332 NULL_TREE if no simplification can be made. */
9334 static tree
9337 {
9338 tree type;
9348 /* Calculate the result when the argument is a constant. */
9353 /* Canonicalize sincos to cexpi. */
9355 {
9358 }
9360 {
9367 }
9379 }
9381 /* Fold function call to builtin memcmp with arguments ARG1 and ARG2.
9382 Return NULL_TREE if no simplification can be made. */
9384 static tree
9386 {
9392 /* If the LEN parameter is zero, return zero. */
9397 /* If ARG1 and ARG2 are the same (and not volatile), return zero. */
9401 /* If len parameter is one, return an expression corresponding to
9402 (*(const unsigned char*)arg1 - (const unsigned char*)arg2). */
9404 {
9406 tree cst_uchar_ptr_node
9409 tree ind1
9413 cst_uchar_ptr_node,
9414 arg1)));
9415 tree ind2
9419 cst_uchar_ptr_node,
9420 arg2)));
9422 }
9425 }
9427 /* Fold a call to builtin isascii with argument ARG. */
9429 static tree
9431 {
9434 else
9435 {
9436 /* Transform isascii(c) -> ((c & ~0x7f) == 0). */
9442 }
9443 }
9445 /* Fold a call to builtin toascii with argument ARG. */
9447 static tree
9449 {
9453 /* Transform toascii(c) -> (c & 0x7f). */
9456 }
9458 /* Fold a call to builtin isdigit with argument ARG. */
9460 static tree
9462 {
9465 else
9466 {
9467 /* Transform isdigit(c) -> (unsigned)(c) - '0' <= 9. */
9468 /* According to the C standard, isdigit is unaffected by locale.
9469 However, it definitely is affected by the target character set. */
9470 unsigned HOST_WIDE_INT target_digit0
9481 }
9482 }
9484 /* Fold a call to fabs, fabsf or fabsl with argument ARG. */
9486 static tree
9488 {
9494 }
9496 /* Fold a call to abs, labs, llabs or imaxabs with argument ARG. */
9498 static tree
9500 {
9506 }
9508 /* Fold a call to builtin carg(a+bi) -> atan2(b,a). */
9510 static tree
9512 {
9515 {
9519 {
9524 }
9525 }
9528 }
9530 /* Fold a call to builtin frexp, we can assume the base is 2. */
9532 static tree
9534 {
9545 /* Proceed if a valid pointer type was passed in. */
9547 {
9552 {
9554 /* For +-0, return (*exp = 0, +-0). */
9560 /* For +-NaN or +-Inf, *exp is unspecified, return arg0. */
9563 {
9564 /* Since the frexp function always expects base 2, and in
9565 GCC normalized significands are already in the range
9566 [0.5, 1.0), we have exactly what frexp wants. */
9571 }
9575 }
9577 /* Create the COMPOUND_EXPR (*arg1 = trunc, frac). */
9581 }
9584 }
9586 /* Fold a call to builtin modf. */
9588 static tree
9590 {
9601 /* Proceed if a valid pointer type was passed in. */
9603 {
9608 {
9611 /* For +-NaN or +-0, return (*arg1 = arg0, arg0). */
9615 /* For +-Inf, return (*arg1 = arg0, +-0). */
9621 /* Return (*arg1 = trunc(arg0), arg0-trunc(arg0)). */
9624 /* If the original number was negative and already
9625 integral, then the fractional part is -0.0. */
9629 }
9631 /* Create the COMPOUND_EXPR (*arg1 = trunc, frac). */
9637 }
9640 }
9642 /* Given a location LOC, an interclass builtin function decl FNDECL
9643 and its single argument ARG, return an folded expression computing
9644 the same, or NULL_TREE if we either couldn't or didn't want to fold
9645 (the latter happen if there's an RTL instruction available). */
9647 static tree
9649 {
9650 machine_mode mode;
9662 /* If there is no optab, try generic code. */
9664 {
9665 tree result;
9668 {
9669 /* isinf(x) -> isgreater(fabs(x),DBL_MAX). */
9672 REAL_VALUE_TYPE r;
9676 {
9677 /* NaN and Inf are encoded in the high-order double value
9678 only. The low-order value is not significant. */
9682 }
9689 }
9692 {
9693 /* isfinite(x) -> islessequal(fabs(x),DBL_MAX). */
9696 REAL_VALUE_TYPE r;
9700 {
9701 /* NaN and Inf are encoded in the high-order double value
9702 only. The low-order value is not significant. */
9706 }
9712 /*result = fold_build2_loc (loc, UNGT_EXPR,
9713 TREE_TYPE (TREE_TYPE (fndecl)),
9714 fold_build1_loc (loc, ABS_EXPR, type, arg),
9715 build_real (type, r));
9716 result = fold_build1_loc (loc, TRUTH_NOT_EXPR,
9717 TREE_TYPE (TREE_TYPE (fndecl)),
9718 result);*/
9720 }
9722 {
9723 /* isnormal(x) -> isgreaterequal(fabs(x),DBL_MIN) &
9724 islessequal(fabs(x),DBL_MAX). */
9734 {
9735 /* Use double to test the normal range of IBM extended
9736 precision. Emin for IBM extended precision is
9737 different to emin for IEEE double, being 53 higher
9738 since the low double exponent is at least 53 lower
9739 than the high double exponent. */
9743 }
9755 {
9756 /* Testing the high end of the range is done just using
9757 the high double, using the same test as isfinite().
9758 For the subnormal end of the range we first test the
9759 high double, then if its magnitude is equal to the
9760 limit of 0x1p-969, we test whether the low double is
9761 non-zero and opposite sign to the high double. */
9777 integer_type_node,
9783 }
9784 else
9785 {
9786 tree const isge_fn
9789 }
9793 }
9796 }
9799 }
9801 /* Fold a call to __builtin_isnan(), __builtin_isinf, __builtin_finite.
9802 ARG is the argument for the call. */
9804 static tree
9806 {
9813 {
9821 {
9822 /* isinf_sign(x) -> isinf(x) ? (signbit(x) ? -1 : 1) : 0 */
9823 /* In a boolean context, GCC will fold the inner COND_EXPR to
9824 1. So e.g. "if (isinf_sign(x))" would be folded to just
9825 "if (isinf(x) ? 1 : 0)" which becomes "if (isinf(x))". */
9833 {
9846 integer_zero_node);
9847 }
9850 }
9863 {
9866 {
9867 /* NaN and Inf are encoded in the high-order double value
9868 only. The low-order value is not significant. */
9870 }
9871 }
9877 }
9878 }
9880 /* Fold a call to __builtin_fpclassify(int, int, int, int, int, ...).
9881 This builtin will generate code to return the appropriate floating
9882 point classification depending on the value of the floating point
9883 number passed in. The possible return values must be supplied as
9884 int arguments to the call in the following order: FP_NAN, FP_INFINITE,
9885 FP_NORMAL, FP_SUBNORMAL and FP_ZERO. The ellipses is for exactly
9886 one floating point argument which is "type generic". */
9888 static tree
9890 {
9893 machine_mode mode;
9894 REAL_VALUE_TYPE r;
9897 /* Verify the required arguments in the original call. */
9917 /* fpclassify(x) ->
9918 isnan(x) ? FP_NAN :
9919 (fabs(x) == Inf ? FP_INFINITE :
9920 (fabs(x) >= DBL_MIN ? FP_NORMAL :
9921 (x == 0 ? FP_ZERO : FP_SUBNORMAL))). */
9935 {
9941 }
9944 {
9947 }
9950 }
9952 /* Fold a call to an unordered comparison function such as
9953 __builtin_isgreater(). FNDECL is the FUNCTION_DECL for the function
9954 being called and ARG0 and ARG1 are the arguments for the call.
9955 UNORDERED_CODE and ORDERED_CODE are comparison codes that give
9956 the opposite of the desired result. UNORDERED_CODE is used
9957 for modes that can hold NaNs and ORDERED_CODE is used for
9958 the rest. */
9960 static tree
9964 {
9978 /* Choose the wider of two real types. */
9990 {
9994 }
9999 }
10001 /* Fold __builtin_{,s,u}{add,sub,mul}{,l,ll}_overflow, either into normal
10002 arithmetics if it can never overflow, or into internal functions that
10003 return both result of arithmetics and overflowed boolean flag in
10004 a complex integer result, or some other check for overflow.
10005 Similarly fold __builtin_{add,sub,mul}_overflow_p to just the overflow
10006 checking part of that. */
10008 static tree
10011 {
10013 /* The code of the expression corresponding to the built-in. */
10018 {
10021 /* FALLTHRU */
10034 /* FALLTHRU */
10047 /* FALLTHRU */
10060 }
10062 /* For the "generic" overloads, the first two arguments can have different
10063 types and the last argument determines the target type to use to check
10064 for overflow. The arguments of the other overloads all have the same
10065 type. */
10068 /* For the __builtin_{add,sub,mul}_overflow_p builtins, when the first two
10069 arguments are constant, attempt to fold the built-in call into a constant
10070 expression indicating whether or not it detected an overflow. */
10074 /* Perform the computation in the target type and check for overflow. */
10078 arg2);
10082 {
10090 }
10091 else
10092 {
10100 }
10106 tree store
10109 }
10111 /* Fold a call to __builtin_FILE to a constant string. */
10115 {
10117 {
10118 /* The documentation says this builtin is equivalent to the preprocessor
10119 __FILE__ macro so it appears appropriate to use the same file prefix
10120 mappings. */
10123 }
10126 }
10128 /* Fold a call to __builtin_FUNCTION to a constant string. */
10132 {
10139 }
10141 /* Fold a call to __builtin_LINE to an integer constant. */
10145 {
10147 }
10149 /* Fold a call to built-in function FNDECL with 0 arguments.
10150 This function returns NULL_TREE if no simplification was possible. */
10152 static tree
10154 {
10158 {
10184 }
10186 }
10188 /* Fold a call to built-in function FNDECL with 1 argument, ARG0.
10189 This function returns NULL_TREE if no simplification was possible. */
10191 static tree
10193 {
10204 {
10206 {
10209 /* Gimplification will pull the CALL_EXPR for the builtin out of
10210 an if condition. When not optimizing, we'll not CSE it back.
10211 To avoid link error types of regressions, return false now. */
10216 }
10272 {
10277 }
10283 {
10288 }
10309 }
10313 }
10315 /* Folds a call EXPR (which may be null) to built-in function FNDECL
10316 with 2 arguments, ARG0 and ARG1. This function returns NULL_TREE
10317 if no simplification was possible. */
10319 static tree
10321 {
10333 {
10377 NOP_EXPR);
10379 /* We do the folding for va_start in the expander. */
10394 }
10396 }
10398 /* Fold a call to built-in function FNDECL with 3 arguments, ARG0, ARG1,
10399 and ARG2.
10400 This function returns NULL_TREE if no simplification was possible. */
10402 static tree
10405 {
10419 {
10468 }
10470 }
10472 /* Folds a call EXPR (which may be null) to built-in function FNDECL.
10473 ARGS is an array of NARGS arguments. IGNORE is true if the result
10474 of the function call is ignored. This function returns NULL_TREE
10475 if no simplification was possible. */
10477 static tree
10480 {
10484 {
10500 }
10502 {
10506 }
10508 }
10510 /* Construct a new CALL_EXPR to FNDECL using the tail of the argument
10511 list ARGS along with N new arguments in NEWARGS. SKIP is the number
10512 of arguments in ARGS to be omitted. OLDNARGS is the number of
10513 elements in ARGS. */
10515 static tree
10518 {
10523 {
10531 }
10532 else
10536 }
10538 /* Return true if FNDECL shouldn't be folded right now.
10539 If a built-in function has an inline attribute always_inline
10540 wrapper, defer folding it after always_inline functions have
10541 been inlined, otherwise e.g. -D_FORTIFY_SOURCE checking
10542 might not be performed. */
10544 bool
10546 {
10549 && cfun
10552 }
10554 /* A wrapper function for builtin folding that prevents warnings for
10555 "statement without effect" and the like, caused by removing the
10556 call node earlier than the warning is generated. */
10558 tree
10560 {
10564 /* If CALL_EXPR_VA_ARG_PACK is set, the arguments aren't finalized
10565 yet. Defer folding until we see all the arguments
10566 (after inlining). */
10568 {
10571 /* Before gimplification CALL_EXPR_VA_ARG_PACK is not set, but
10572 instead last argument is __builtin_va_arg_pack (). Defer folding
10573 even in that case, until arguments are finalized. */
10575 {
10579 }
10587 else
10588 {
10593 }
10594 }
10596 }
10598 /* Fold a CALL_EXPR with type TYPE with FN as the function expression.
10599 N arguments are passed in the array ARGARRAY. Return a folded
10600 expression or NULL_TREE if no simplification was possible. */
10602 tree
10604 tree fn,
10607 {
10614 {
10615 /* If last argument is __builtin_va_arg_pack (), arguments to this
10616 function are not finalized yet. Defer folding until they are. */
10618 {
10622 }
10627 else
10629 }
10632 }
10634 /* Construct a new CALL_EXPR using the tail of the argument list of EXP
10635 along with N new arguments specified as the "..." parameters. SKIP
10636 is the number of arguments in EXP to be omitted. This function is used
10637 to do varargs-to-varargs transformations. */
10639 static tree
10641 {
10643 tree t;
10651 }
10653 /* Validate a single argument ARG against a tree code CODE representing
10654 a type. Return true when argument is valid. */
10656 static bool
10658 {
10666 }
10668 /* This function validates the types of a function call argument list
10669 against a specified list of tree_codes. If the last specifier is a 0,
10670 that represents an ellipses, otherwise the last specifier must be a
10671 VOID_TYPE.
10673 This is the GIMPLE version of validate_arglist. Eventually we want to
10674 completely convert builtins.c to work from GIMPLEs and the tree based
10675 validate_arglist will then be removed. */
10677 bool
10679 {
10683 const_tree arg;
10689 do
10690 {
10693 {
10695 /* This signifies an ellipses, any further arguments are all ok. */
10699 /* This signifies an endlink, if no arguments remain, return
10700 true, otherwise return false. */
10704 /* If no parameters remain or the parameter's code does not
10705 match the specified code, return false. Otherwise continue
10706 checking any remaining arguments. */
10711 }
10712 }
10715 /* We need gotos here since we can only have one VA_CLOSE in a
10716 function. */
10717 end: ;
10721 }
10723 /* Default target-specific builtin expander that does nothing. */
10725 rtx
10727 rtx target ATTRIBUTE_UNUSED,
10728 rtx subtarget ATTRIBUTE_UNUSED,
10729 machine_mode mode ATTRIBUTE_UNUSED,
10731 {
10733 }
10735 /* Returns true is EXP represents data that would potentially reside
10736 in a readonly section. */
10738 bool
10740 {
10750 /* Make sure we call decl_readonly_section only for trees it
10751 can handle (since it returns true for everything it doesn't
10752 understand). */
10757 else
10759 }
10761 /* Simplify a call to the strpbrk builtin. S1 and S2 are the arguments
10762 to the call, and TYPE is its return type.
10764 Return NULL_TREE if no simplification was possible, otherwise return the
10765 simplified form of the call as a tree.
10767 The simplified form may be a constant or other expression which
10768 computes the same value, but in a more efficient manner (including
10769 calls to other builtin functions).
10771 The call may contain arguments which need to be evaluated, but
10772 which are not useful to determine the result of the call. In
10773 this case we return a chain of COMPOUND_EXPRs. The LHS of each
10774 COMPOUND_EXPR will be an argument which must be evaluated.
10775 COMPOUND_EXPRs are chained through their RHS. The RHS of the last
10776 COMPOUND_EXPR in the chain will contain the tree for the simplified
10777 form of the builtin function call. */
10779 static tree
10781 {
10790 tree fn;
10799 {
10801 tree tem;
10806 /* Return an offset into the constant string argument. */
10809 }
10812 /* strpbrk(x, "") == NULL.
10813 Evaluate and ignore s1 in case it had side-effects. */
10823 /* New argument list transforming strpbrk(s1, s2) to
10824 strchr(s1, s2[0]). */
10827 }
10829 /* Simplify a call to the strspn builtin. S1 and S2 are the arguments
10830 to the call.
10832 Return NULL_TREE if no simplification was possible, otherwise return the
10833 simplified form of the call as a tree.
10835 The simplified form may be a constant or other expression which
10836 computes the same value, but in a more efficient manner (including
10837 calls to other builtin functions).
10839 The call may contain arguments which need to be evaluated, but
10840 which are not useful to determine the result of the call. In
10841 this case we return a chain of COMPOUND_EXPRs. The LHS of each
10842 COMPOUND_EXPR will be an argument which must be evaluated.
10843 COMPOUND_EXPRs are chained through their RHS. The RHS of the last
10844 COMPOUND_EXPR in the chain will contain the tree for the simplified
10845 form of the builtin function call. */
10847 static tree
10849 {
10860 /* If either argument is "", return NULL_TREE. */
10862 /* Evaluate and ignore both arguments in case either one has
10863 side-effects. */
10867 }
10869 /* Simplify a call to the strcspn builtin. S1 and S2 are the arguments
10870 to the call.
10872 Return NULL_TREE if no simplification was possible, otherwise return the
10873 simplified form of the call as a tree.
10875 The simplified form may be a constant or other expression which
10876 computes the same value, but in a more efficient manner (including
10877 calls to other builtin functions).
10879 The call may contain arguments which need to be evaluated, but
10880 which are not useful to determine the result of the call. In
10881 this case we return a chain of COMPOUND_EXPRs. The LHS of each
10882 COMPOUND_EXPR will be an argument which must be evaluated.
10883 COMPOUND_EXPRs are chained through their RHS. The RHS of the last
10884 COMPOUND_EXPR in the chain will contain the tree for the simplified
10885 form of the builtin function call. */
10887 static tree
10889 {
10898 /* If the first argument is "", return NULL_TREE. */
10901 {
10902 /* Evaluate and ignore argument s2 in case it has
10903 side-effects. */
10906 }
10908 /* If the second argument is "", return __builtin_strlen(s1). */
10911 {
10914 /* If the replacement _DECL isn't initialized, don't do the
10915 transformation. */
10920 }
10922 }
10924 /* Fold the next_arg or va_start call EXP. Returns true if there was an error
10925 produced. False otherwise. This is done so that we don't output the error
10926 or warning twice or three times. */
10928 bool
10930 {
10933 tree arg;
10934 /* There is good chance the current input_location points inside the
10935 definition of the va_start macro (perhaps on the token for
10936 builtin) in a system header, so warnings will not be emitted.
10937 Use the location in real source code. */
10938 location_t current_location =
10940 NULL);
10943 {
10946 }
10949 {
10951 {
10954 }
10956 }
10957 /* We use __builtin_va_start (ap, 0, 0) or __builtin_next_arg (0, 0)
10958 when we checked the arguments and if needed issued a warning. */
10959 else
10960 {
10962 {
10963 /* Evidently an out of date version of <stdarg.h>; can't validate
10964 va_start's second argument, but can still work as intended. */
10966 OPT_Wvarargs,
10969 }
10971 {
10974 }
10976 }
10981 /* We destructively modify the call to be __builtin_va_start (ap, 0)
10982 or __builtin_next_arg (0) the first time we see it, after checking
10983 the arguments and if needed issuing a warning. */
10985 {
10988 /* Strip off all nops for the sake of the comparison. This
10989 is not quite the same as STRIP_NOPS. It does more.
10990 We must also strip off INDIRECT_EXPR for C++ reference
10991 parameters. */
10996 {
10997 /* FIXME: Sometimes with the tree optimizers we can get the
10998 not the last argument even though the user used the last
10999 argument. We just warn and set the arg to be the last
11000 argument so that we will get wrong-code because of
11001 it. */
11003 OPT_Wvarargs,
11005 }
11007 /* Undefined by C99 7.15.1.4p4 (va_start):
11008 "If the parameter parmN is declared with the register storage
11009 class, with a function or array type, or with a type that is
11010 not compatible with the type that results after application of
11011 the default argument promotions, the behavior is undefined."
11012 */
11014 {
11016 OPT_Wvarargs,
11017 "undefined behavior when second parameter of "
11019 }
11021 /* We want to verify the second parameter just once before the tree
11022 optimizers are run and then avoid keeping it in the tree,
11023 as otherwise we could warn even for correct code like:
11024 void foo (int i, ...)
11025 { va_list ap; i++; va_start (ap, i); va_end (ap); } */
11028 else
11030 }
11032 }
11035 /* Expand a call EXP to __builtin_object_size. */
11037 static rtx
11039 {
11040 tree ost;
11045 {
11050 }
11058 {
11063 }
11068 }
11070 /* Expand EXP, a call to the __mem{cpy,pcpy,move,set}_chk builtin.
11071 FCODE is the BUILT_IN_* to use.
11072 Return NULL_RTX if we failed; the caller should emit a normal call,
11073 otherwise try to get the result in TARGET, if convenient (and in
11074 mode MODE if that's convenient). */
11076 static rtx
11079 {
11081 POINTER_TYPE,
11082 fcode == BUILT_IN_MEMSET_CHK
11099 {
11100 /* Avoid transforming the checking call to an ordinary one when
11101 an overflow has been detected or when the call couldn't be
11102 validated because the size is not constant. */
11107 /* If __builtin_mem{cpy,pcpy,move,set}_chk is used, assume
11108 mem{cpy,pcpy,move,set} is available. */
11110 {
11125 }
11134 }
11137 else
11138 {
11141 /* If DEST is not a pointer type, call the normal function. */
11145 /* If SRC and DEST are the same (and not volatile), do nothing. */
11147 {
11148 tree expr;
11151 {
11152 /* Evaluate and ignore LEN in case it has side-effects. */
11155 }
11159 }
11161 /* __memmove_chk special case. */
11163 {
11169 /* If src is categorized for a readonly section we can use
11170 normal __memcpy_chk. */
11172 {
11181 }
11182 }
11184 }
11185 }
11187 /* Emit warning if a buffer overflow is detected at compile time. */
11189 static void
11191 {
11192 /* The source string. */
11194 /* The size of the destination object. */
11196 /* The string that is being concatenated with (as in __strcat_chk)
11197 or null if it isn't. */
11199 /* The maximum length of the source sequence in a bounded operation
11200 (such as __strncat_chk) or null if the operation isn't bounded
11201 (such as __strcat_chk). */
11203 /* The exact size of the access (such as in __strncpy_chk). */
11207 {
11215 /* For __strcat_chk the warning will be emitted only if overflowing
11216 by at least strlen (dest) + 1 bytes. */
11243 }
11246 {
11247 /* Check __strncat_chk. There is no way to determine the length
11248 of the string to which the source string is being appended so
11249 just warn when the length of the source string is not known. */
11252 }
11254 /* The destination argument is the first one for all built-ins above. */
11258 }
11260 /* Emit warning if a buffer overflow is detected at compile time
11261 in __sprintf_chk/__vsprintf_chk calls. */
11263 static void
11265 {
11270 /* Verify the required arguments in the original call. */
11280 /* Check whether the format is a literal string constant. */
11288 /* If the format doesn't contain % args or %%, we know its size. */
11291 /* If the format is "%s" and first ... argument is a string literal,
11292 we know it too. */
11295 {
11296 tree arg;
11307 }
11308 else
11311 /* Add one for the terminating nul. */
11316 }
11318 /* Emit warning if a free is called with address of a variable. */
11320 static void
11322 {
11339 else
11342 }
11344 /* Fold a call to __builtin_object_size with arguments PTR and OST,
11345 if possible. */
11347 static tree
11349 {
11366 /* __builtin_object_size doesn't evaluate side-effects in its arguments;
11367 if there are any side-effects, it returns (size_t) -1 for types 0 and 1
11368 and (size_t) 0 for types 2 and 3. */
11373 {
11377 }
11379 {
11380 /* If object size is not known yet, delay folding until
11381 later. Maybe subsequent passes will help determining
11382 it. */
11386 }
11389 }
11391 /* Builtins with folding operations that operate on "..." arguments
11392 need special handling; we need to store the arguments in a convenient
11393 data structure before attempting any folding. Fortunately there are
11394 only a few builtins that fall into this category. FNDECL is the
11395 function, EXP is the CALL_EXPR for the call. */
11397 static tree
11399 {
11404 {
11411 }
11413 {
11418 }
11420 }
11422 /* Initialize format string characters in the target charset. */
11424 bool
11426 {
11429 {
11452 }
11454 }
11456 /* Helper function for do_mpfr_arg*(). Ensure M is a normal number
11457 and no overflow/underflow occurred. INEXACT is true if M was not
11458 exactly calculated. TYPE is the tree type for the result. This
11459 function assumes that you cleared the MPFR flags and then
11460 calculated M to see if anything subsequently set a flag prior to
11461 entering this function. Return NULL_TREE if any checks fail. */
11463 static tree
11465 {
11466 /* Proceed iff we get a normal number, i.e. not NaN or Inf and no
11467 overflow/underflow occurred. If -frounding-math, proceed iff the
11468 result of calling FUNC was exact. */
11471 {
11472 REAL_VALUE_TYPE rr;
11475 /* Proceed iff GCC's REAL_VALUE_TYPE can hold the MPFR value,
11476 check for overflow/underflow. If the REAL_VALUE_TYPE is zero
11477 but the mpft_t is not, then we underflowed in the
11478 conversion. */
11481 {
11482 REAL_VALUE_TYPE rmode;
11485 /* Proceed iff the specified mode can hold the value. */
11488 }
11489 }
11491 }
11493 /* Helper function for do_mpc_arg*(). Ensure M is a normal complex
11494 number and no overflow/underflow occurred. INEXACT is true if M
11495 was not exactly calculated. TYPE is the tree type for the result.
11496 This function assumes that you cleared the MPFR flags and then
11497 calculated M to see if anything subsequently set a flag prior to
11498 entering this function. Return NULL_TREE if any checks fail, if
11499 FORCE_CONVERT is true, then bypass the checks. */
11501 static tree
11503 {
11504 /* Proceed iff we get a normal number, i.e. not NaN or Inf and no
11505 overflow/underflow occurred. If -frounding-math, proceed iff the
11506 result of calling FUNC was exact. */
11511 {
11516 /* Proceed iff GCC's REAL_VALUE_TYPE can hold the MPFR values,
11517 check for overflow/underflow. If the REAL_VALUE_TYPE is zero
11518 but the mpft_t is not, then we underflowed in the
11519 conversion. */
11524 {
11529 /* Proceed iff the specified mode can hold the value. */
11535 }
11536 }
11538 }
11540 /* If arguments ARG0 and ARG1 are REAL_CSTs, call mpfr_remquo() to set
11541 the pointer *(ARG_QUO) and return the result. The type is taken
11542 from the type of ARG0 and is used for setting the precision of the
11543 calculation and results. */
11545 static tree
11547 {
11554 /* To proceed, MPFR must exactly represent the target floating point
11555 format, which only happens when the target base equals two. */
11559 {
11564 {
11568 tree result_rem;
11577 /* Remquo is independent of the rounding mode, so pass
11578 inexact=0 to do_mpfr_ckconv(). */
11582 {
11583 /* MPFR calculates quo in the host's long so it may
11584 return more bits in quo than the target int can hold
11585 if sizeof(host long) > sizeof(target int). This can
11586 happen even for native compilers in LP64 mode. In
11587 these cases, modulo the quo value with the largest
11588 number that the target int can hold while leaving one
11589 bit for the sign. */
11593 /* Dereference the quo pointer argument. */
11595 /* Proceed iff a valid pointer type was passed in. */
11597 {
11598 /* Set the value. */
11599 tree result_quo
11602 integer_quo));
11604 /* Combine the quo assignment with the rem. */
11607 }
11608 }
11609 }
11610 }
11612 }
11614 /* If ARG is a REAL_CST, call mpfr_lgamma() on it and return the
11615 resulting value as a tree with type TYPE. The mpfr precision is
11616 set to the precision of TYPE. We assume that this mpfr function
11617 returns zero if the result could be calculated exactly within the
11618 requested precision. In addition, the integer pointer represented
11619 by ARG_SG will be dereferenced and set to the appropriate signgam
11620 (-1,1) value. */
11622 static tree
11624 {
11629 /* To proceed, MPFR must exactly represent the target floating point
11630 format, which only happens when the target base equals two. Also
11631 verify ARG is a constant and that ARG_SG is an int pointer. */
11636 {
11639 /* In addition to NaN and Inf, the argument cannot be zero or a
11640 negative integer. */
11644 {
11649 mpfr_t m;
11650 tree result_lg;
11659 {
11660 tree result_sg;
11662 /* Dereference the arg_sg pointer argument. */
11664 /* Assign the signgam value into *arg_sg. */
11669 /* Combine the signgam assignment with the lgamma result. */
11672 }
11673 }
11674 }
11677 }
11679 /* If arguments ARG0 and ARG1 are a COMPLEX_CST, call the two-argument
11680 mpc function FUNC on it and return the resulting value as a tree
11681 with type TYPE. The mpfr precision is set to the precision of
11682 TYPE. We assume that function FUNC returns zero if the result
11683 could be calculated exactly within the requested precision. If
11684 DO_NONFINITE is true, then fold expressions containing Inf or NaN
11685 in the arguments and/or results. */
11687 tree
11690 {
11696 /* To proceed, MPFR must exactly represent the target floating point
11697 format, which only happens when the target base equals two. */
11703 {
11712 {
11733 }
11734 }
11737 }
11739 /* A wrapper function for builtin folding that prevents warnings for
11740 "statement without effect" and the like, caused by removing the
11741 call node earlier than the warning is generated. */
11743 tree
11745 {
11751 {
11760 {
11762 }
11763 else
11764 {
11767 {
11768 /* Propagate location information from original call to
11769 expansion of builtin. Otherwise things like
11770 maybe_emit_chk_warning, that operate on the expansion
11771 of a builtin, will use the wrong location information. */
11773 {
11781 }
11783 }
11784 }
11785 }
11787 }
11789 /* Look up the function in builtin_decl that corresponds to DECL
11790 and set ASMSPEC as its user assembler name. DECL must be a
11791 function decl that declares a builtin. */
11793 void
11795 {
11804 {
11808 }
11809 }
11811 /* Return true if DECL is a builtin that expands to a constant or similarly
11812 simple code. */
11813 bool
11815 {
11818 {
11819 /* Builtins that expand to constants. */
11824 /* Simple register moves or loads from stack. */
11835 /* Exception state returns or moves registers around. */
11843 }
11846 }
11848 /* Return true if DECL is a builtin that is not expensive, i.e., they are
11849 most probably expanded inline into reasonably simple code. This is a
11850 superset of is_simple_builtin. */
11851 bool
11853 {
11860 {
11862 CASE_BUILT_IN_ALLOCA:
11929 }
11932 }
11934 /* Return true if T is a constant and the value cast to a target char
11935 can be represented by a host char.
11936 Store the casted char constant in *P if so. */
11938 bool
11940 {
11946 }
11948 /* Return true if the builtin DECL is implemented in a standard library.
11949 Otherwise returns false which doesn't guarantee it is not (thus the list of
11950 handled builtins below may be incomplete). */
11952 bool
11954 {
11957 {
12031 }
12033 }