https://gcc.gnu.org/g:b4b872b2195b448b3e1bcd28c3e28d59618580a2
commit b4b872b2195b448b3e1bcd28c3e28d59618580a2
Author: Alexandre Oliva <ol...@adacore.com>
Date: Fri Sep 13 21:43:00 2024 -0300
rework truth_andor folding into tree-ssa-ifcombine
Diff:
---
gcc/fold-const.cc | 1048 +----------------------------------------
gcc/gimple-fold.cc | 1149 +++++++++++++++++++++++++++++++++++++++++++++
gcc/tree-ssa-ifcombine.cc | 7 +-
3 files changed, 1170 insertions(+), 1034 deletions(-)
diff --git a/gcc/fold-const.cc b/gcc/fold-const.cc
index 81814de5b04b..19824e6a477f 100644
--- a/gcc/fold-const.cc
+++ b/gcc/fold-const.cc
@@ -137,7 +137,6 @@ static tree range_successor (tree);
static tree fold_range_test (location_t, enum tree_code, tree, tree, tree);
static tree fold_cond_expr_with_comparison (location_t, tree, enum tree_code,
tree, tree, tree, tree);
-static tree unextend (tree, int, int, tree);
static tree extract_muldiv (tree, tree, enum tree_code, tree, bool *);
static tree extract_muldiv_1 (tree, tree, enum tree_code, tree, bool *);
static tree fold_binary_op_with_conditional_arg (location_t,
@@ -4695,7 +4694,7 @@ invert_truthvalue_loc (location_t loc, tree arg)
is the original memory reference used to preserve the alias set of
the access. */
-static tree
+tree
make_bit_field_ref (location_t loc, tree inner, tree orig_inner, tree type,
HOST_WIDE_INT bitsize, poly_int64 bitpos,
int unsignedp, int reversep)
@@ -4945,212 +4944,6 @@ optimize_bit_field_compare (location_t loc, enum
tree_code code,
return lhs;
}
-/* If *R_ARG is a constant zero, and L_ARG is a possibly masked
- BIT_XOR_EXPR, return 1 and set *r_arg to l_arg.
- Otherwise, return 0.
-
- The returned value should be passed to decode_field_reference for it
- to handle l_arg, and then doubled for r_arg. */
-static int
-prepare_xor (tree l_arg, tree *r_arg)
-{
- int ret = 0;
-
- if (!integer_zerop (*r_arg))
- return ret;
-
- tree exp = l_arg;
- STRIP_NOPS (exp);
-
- if (TREE_CODE (exp) == BIT_AND_EXPR)
- {
- tree and_mask = TREE_OPERAND (exp, 1);
- exp = TREE_OPERAND (exp, 0);
- STRIP_NOPS (exp); STRIP_NOPS (and_mask);
- if (TREE_CODE (and_mask) != INTEGER_CST)
- return ret;
- }
-
- if (TREE_CODE (exp) == BIT_XOR_EXPR)
- {
- *r_arg = l_arg;
- return 1;
- }
-
- return ret;
-}
-
-/* Subroutine for fold_truth_andor_1: decode a field reference.
-
- If EXP is a comparison reference, we return the innermost reference.
-
- *PBITSIZE is set to the number of bits in the reference, *PBITPOS is
- set to the starting bit number.
-
- If the innermost field can be completely contained in a mode-sized
- unit, *PMODE is set to that mode. Otherwise, it is set to VOIDmode.
-
- *PVOLATILEP is set to 1 if the any expression encountered is volatile;
- otherwise it is not changed.
-
- *PUNSIGNEDP is set to the signedness of the field.
-
- *PREVERSEP is set to the storage order of the field.
-
- *PMASK is set to the mask used. This is either contained in a
- BIT_AND_EXPR or derived from the width of the field.
-
- *PAND_MASK is set to the mask found in a BIT_AND_EXPR, if any.
-
- XOR_WHICH is 1 or 2 if EXP was found to be a (possibly masked)
- BIT_XOR_EXPR compared with zero. We're to take the first or second
- operand thereof if so. It should be zero otherwise.
-
- Return 0 if this is not a component reference or is one that we can't
- do anything with. */
-
-static tree
-decode_field_reference (location_t loc, tree *exp_, HOST_WIDE_INT *pbitsize,
- HOST_WIDE_INT *pbitpos, machine_mode *pmode,
- int *punsignedp, int *preversep, int *pvolatilep,
- tree *pmask, tree *pand_mask, int xor_which)
-{
- tree exp = *exp_;
- tree outer_type = 0;
- tree and_mask = 0;
- tree mask, inner, offset;
- tree unsigned_type;
- unsigned int precision;
- HOST_WIDE_INT shiftrt = 0;
-
- /* All the optimizations using this function assume integer fields.
- There are problems with FP fields since the type_for_size call
- below can fail for, e.g., XFmode. */
- if (! INTEGRAL_TYPE_P (TREE_TYPE (exp)))
- return NULL_TREE;
-
- /* We are interested in the bare arrangement of bits, so strip everything
- that doesn't affect the machine mode. However, record the type of the
- outermost expression if it may matter below. */
- if (CONVERT_EXPR_P (exp)
- || TREE_CODE (exp) == NON_LVALUE_EXPR)
- outer_type = TREE_TYPE (exp);
- STRIP_NOPS (exp);
-
- if (TREE_CODE (exp) == BIT_AND_EXPR)
- {
- and_mask = TREE_OPERAND (exp, 1);
- exp = TREE_OPERAND (exp, 0);
- STRIP_NOPS (exp); STRIP_NOPS (and_mask);
- if (TREE_CODE (and_mask) != INTEGER_CST)
- return NULL_TREE;
- }
-
- if (xor_which)
- {
- gcc_checking_assert (TREE_CODE (exp) == BIT_XOR_EXPR);
- exp = TREE_OPERAND (exp, xor_which - 1);
- STRIP_NOPS (exp);
- }
-
- if (CONVERT_EXPR_P (exp)
- || TREE_CODE (exp) == NON_LVALUE_EXPR)
- {
- if (!outer_type)
- outer_type = TREE_TYPE (exp);
- exp = TREE_OPERAND (exp, 0);
- STRIP_NOPS (exp);
- }
-
- if (TREE_CODE (exp) == RSHIFT_EXPR
- && TREE_CODE (TREE_OPERAND (exp, 1)) == INTEGER_CST
- && tree_fits_shwi_p (TREE_OPERAND (exp, 1)))
- {
- tree shift = TREE_OPERAND (exp, 1);
- STRIP_NOPS (shift);
- shiftrt = tree_to_shwi (shift);
- if (shiftrt > 0)
- {
- exp = TREE_OPERAND (exp, 0);
- STRIP_NOPS (exp);
- }
- else
- shiftrt = 0;
- }
-
- if (CONVERT_EXPR_P (exp)
- || TREE_CODE (exp) == NON_LVALUE_EXPR)
- {
- if (!outer_type)
- outer_type = TREE_TYPE (exp);
- exp = TREE_OPERAND (exp, 0);
- STRIP_NOPS (exp);
- }
-
- poly_int64 poly_bitsize, poly_bitpos;
- inner = get_inner_reference (exp, &poly_bitsize, &poly_bitpos, &offset,
- pmode, punsignedp, preversep, pvolatilep);
-
- if ((inner == exp && and_mask == 0)
- || !poly_bitsize.is_constant (pbitsize)
- || !poly_bitpos.is_constant (pbitpos)
- || *pbitsize <= shiftrt
- || offset != 0
- || TREE_CODE (inner) == PLACEHOLDER_EXPR
- /* We eventually want to build a larger reference and need to take
- the address of this. */
- || (!REFERENCE_CLASS_P (inner) && !DECL_P (inner))
- /* Reject out-of-bound accesses (PR79731). */
- || (! AGGREGATE_TYPE_P (TREE_TYPE (inner))
- && compare_tree_int (TYPE_SIZE (TREE_TYPE (inner)),
- *pbitpos + *pbitsize) < 0))
- return NULL_TREE;
-
- if (shiftrt)
- {
- if (!*preversep ? !BYTES_BIG_ENDIAN : BYTES_BIG_ENDIAN)
- *pbitpos += shiftrt;
- *pbitsize -= shiftrt;
- }
-
- if (outer_type && *pbitsize > TYPE_PRECISION (outer_type))
- {
- HOST_WIDE_INT excess = *pbitsize - TYPE_PRECISION (outer_type);
- if (*preversep ? !BYTES_BIG_ENDIAN : BYTES_BIG_ENDIAN)
- *pbitpos += excess;
- *pbitsize -= excess;
- }
-
- unsigned_type = lang_hooks.types.type_for_size (*pbitsize, 1);
- if (unsigned_type == NULL_TREE)
- return NULL_TREE;
-
- *exp_ = exp;
-
- /* If the number of bits in the reference is the same as the bitsize of
- the outer type, then the outer type gives the signedness. Otherwise
- (in case of a small bitfield) the signedness is unchanged. */
- if (outer_type && *pbitsize == TYPE_PRECISION (outer_type))
- *punsignedp = TYPE_UNSIGNED (outer_type);
-
- /* Compute the mask to access the bitfield. */
- precision = TYPE_PRECISION (unsigned_type);
-
- mask = build_int_cst_type (unsigned_type, -1);
-
- mask = const_binop (LSHIFT_EXPR, mask, size_int (precision - *pbitsize));
- mask = const_binop (RSHIFT_EXPR, mask, size_int (precision - *pbitsize));
-
- /* Merge it with the mask we found in the BIT_AND_EXPR, if any. */
- if (and_mask != 0)
- mask = fold_build2_loc (loc, BIT_AND_EXPR, unsigned_type,
- fold_convert_loc (loc, unsigned_type, and_mask), mask);
-
- *pmask = mask;
- *pand_mask = and_mask;
- return inner;
-}
-
/* Subroutine for fold: determine if VAL is the INTEGER_CONST that
represents the sign bit of EXP's type. If EXP represents a sign
or zero extension, also test VAL against the unextended type.
@@ -6460,48 +6253,6 @@ fold_range_test (location_t loc, enum tree_code code,
tree type,
return 0;
}
-/* Subroutine for fold_truth_andor_1: C is an INTEGER_CST interpreted as a P
- bit value. Arrange things so the extra bits will be set to zero if and
- only if C is signed-extended to its full width. If MASK is nonzero,
- it is an INTEGER_CST that should be AND'ed with the extra bits. */
-
-static tree
-unextend (tree c, int p, int unsignedp, tree mask)
-{
- tree type = TREE_TYPE (c);
- int modesize = GET_MODE_BITSIZE (SCALAR_INT_TYPE_MODE (type));
- tree temp;
-
- if (p == modesize || unsignedp)
- return c;
-
- /* We work by getting just the sign bit into the low-order bit, then
- into the high-order bit, then sign-extend. We then XOR that value
- with C. */
- temp = build_int_cst (TREE_TYPE (c),
- wi::extract_uhwi (wi::to_wide (c), p - 1, 1));
-
- /* We must use a signed type in order to get an arithmetic right shift.
- However, we must also avoid introducing accidental overflows, so that
- a subsequent call to integer_zerop will work. Hence we must
- do the type conversion here. At this point, the constant is either
- zero or one, and the conversion to a signed type can never overflow.
- We could get an overflow if this conversion is done anywhere else. */
- if (TYPE_UNSIGNED (type))
- temp = fold_convert (signed_type_for (type), temp);
-
- temp = const_binop (LSHIFT_EXPR, temp, size_int (modesize - 1));
- temp = const_binop (RSHIFT_EXPR, temp, size_int (modesize - p - 1));
- if (mask != 0)
- temp = const_binop (BIT_AND_EXPR, temp,
- fold_convert (TREE_TYPE (c), mask));
- /* If necessary, convert the type back to match the type of C. */
- if (TYPE_UNSIGNED (type))
- temp = fold_convert (type, temp);
-
- return fold_convert (type, const_binop (BIT_XOR_EXPR, c, temp));
-}
-
/* For an expression that has the form
(A && B) || ~B
or
@@ -6572,153 +6323,13 @@ merge_truthop_with_opposite_arm (location_t loc, tree
op, tree cmpop,
lhs, rhs);
return NULL_TREE;
}
-
-/* Return the one bitpos within bit extents L or R that is at an
- ALIGN-bit alignment boundary, or -1 if there is more than one such
- boundary, if there isn't any, or if there is any such boundary
- between the extents. L and R are given by bitpos and bitsize. If
- it doesn't return -1, there are two consecutive ALIGN-bit words
- that contain both extents, and at least one of the extents
- straddles across the returned alignment boundary. */
-static inline HOST_WIDE_INT
-compute_split_boundary_from_align (HOST_WIDE_INT align,
- HOST_WIDE_INT l_bitpos,
- HOST_WIDE_INT l_bitsize,
- HOST_WIDE_INT r_bitpos,
- HOST_WIDE_INT r_bitsize)
-{
- HOST_WIDE_INT amask = ~(align - 1);
-
- HOST_WIDE_INT first_bit = MIN (l_bitpos, r_bitpos);
- HOST_WIDE_INT end_bit = MAX (l_bitpos + l_bitsize, r_bitpos + r_bitsize);
-
- HOST_WIDE_INT boundary = (end_bit - 1) & amask;
-
- /* Make sure we're crossing no more than one alignment boundary.
-
- ??? We don't have logic to recombine loads of two adjacent
- fields that each crosses a different alignment boundary, so
- as to load the middle word only once, if other words can't be
- otherwise recombined. */
- if (boundary - first_bit > align)
- return -1;
-
- HOST_WIDE_INT l_start_word = l_bitpos & amask;
- HOST_WIDE_INT l_end_word = (l_bitpos + l_bitsize - 1) & amask;
-
- HOST_WIDE_INT r_start_word = r_bitpos & amask;
- HOST_WIDE_INT r_end_word = (r_bitpos + r_bitsize - 1) & amask;
-
- /* If neither field straddles across an alignment boundary, it's no
- use to even try to merge them. */
- if (l_start_word == l_end_word && r_start_word == r_end_word)
- return -1;
-
- return boundary;
-}
-
-/* Initialize ln_arg[0] and ln_arg[1] to a pair of newly-created (at
- LOC) loads from INNER (from ORIG_INNER), of modes MODE and MODE2,
- respectively, starting at BIT_POS, using reversed endianness if
- REVERSEP. Also initialize BITPOS (the starting position of each
- part into INNER), BITSIZ (the bit count starting at BITPOS),
- TOSHIFT[1] (the amount by which the part and its mask are to be
- shifted right to bring its least-significant bit to bit zero) and
- SHIFTED (the amount by which the part, by separate loading, has
- already been shifted right, but that the mask needs shifting to
- match). */
-static inline void
-build_split_load (tree /* out */ ln_arg[2],
- HOST_WIDE_INT /* out */ bitpos[2],
- HOST_WIDE_INT /* out */ bitsiz[2],
- HOST_WIDE_INT /* in[0] out[0..1] */ toshift[2],
- HOST_WIDE_INT /* out */ shifted[2],
- location_t loc, tree inner, tree orig_inner,
- scalar_int_mode mode, scalar_int_mode mode2,
- HOST_WIDE_INT bit_pos, bool reversep)
-{
- bitsiz[0] = GET_MODE_BITSIZE (mode);
- bitsiz[1] = GET_MODE_BITSIZE (mode2);
-
- for (int i = 0; i < 2; i++)
- {
- tree type = lang_hooks.types.type_for_size (bitsiz[i], 1);
- bitpos[i] = bit_pos;
- ln_arg[i] = make_bit_field_ref (loc, inner, orig_inner,
- type, bitsiz[i],
- bit_pos, 1, reversep);
- bit_pos += bitsiz[i];
- }
-
- toshift[1] = toshift[0];
- if (reversep ? !BYTES_BIG_ENDIAN : BYTES_BIG_ENDIAN)
- {
- shifted[0] = bitsiz[1];
- shifted[1] = 0;
- toshift[0] = 0;
- }
- else
- {
- shifted[1] = bitsiz[0];
- shifted[0] = 0;
- toshift[1] = 0;
- }
-}
-
-/* Make arrangements to split at bit BOUNDARY a single loaded word
- (with REVERSEP bit order) LN_ARG[0], to be shifted right by
- TOSHIFT[0] to bring the field of interest to the least-significant
- bit. The expectation is that the same loaded word will be
- propagated from part 0 to part 1, with just different shifting and
- masking to extract both parts. MASK is not expected to do more
- than masking out the bits that belong to the other part. See
- build_split_load for more information on the other fields. */
-static inline void
-reuse_split_load (tree /* in[0] out[1] */ ln_arg[2],
- HOST_WIDE_INT /* in[0] out[1] */ bitpos[2],
- HOST_WIDE_INT /* in[0] out[1] */ bitsiz[2],
- HOST_WIDE_INT /* in[0] out[0..1] */ toshift[2],
- HOST_WIDE_INT /* out */ shifted[2],
- tree /* out */ mask[2],
- HOST_WIDE_INT boundary, bool reversep)
-{
- ln_arg[1] = ln_arg[0];
- bitpos[1] = bitpos[0];
- bitsiz[1] = bitsiz[0];
- shifted[1] = shifted[0] = 0;
-
- tree basemask = build_int_cst_type (TREE_TYPE (ln_arg[0]), -1);
-
- if (reversep ? !BYTES_BIG_ENDIAN : BYTES_BIG_ENDIAN)
- {
- toshift[1] = toshift[0];
- toshift[0] = bitpos[0] + bitsiz[0] - boundary;
- mask[0] = const_binop (LSHIFT_EXPR, basemask,
- bitsize_int (toshift[0]));
- mask[1] = const_binop (BIT_XOR_EXPR, basemask, mask[0]);
- }
- else
- {
- toshift[1] = boundary - bitpos[1];
- mask[1] = const_binop (LSHIFT_EXPR, basemask,
- bitsize_int (toshift[1]));
- mask[0] = const_binop (BIT_XOR_EXPR, basemask, mask[1]);
- }
-}
-
+
/* Find ways of folding logical expressions of LHS and RHS:
Try to merge two comparisons to the same innermost item.
Look for range tests like "ch >= '0' && ch <= '9'".
Look for combinations of simple terms on machines with expensive branches
and evaluate the RHS unconditionally.
- For example, if we have p->a == 2 && p->b == 4 and we can make an
- object large enough to span both A and B, we can do this with a comparison
- against the object ANDed with the a mask.
-
- If we have p->a == q->a && p->b == q->b, we may be able to use bit masking
- operations to do this with one comparison.
-
We check for both normal comparisons and the BIT_AND_EXPRs made this by
function and the one above.
@@ -6728,19 +6339,11 @@ reuse_split_load (tree /* in[0] out[1] */ ln_arg[2],
TRUTH_TYPE is the type of the logical operand and LHS and RHS are its
two operands.
- SEPARATEP should be NULL if LHS and RHS are adjacent in
- CODE-chained compares, and a non-NULL pointer to NULL_TREE
- otherwise. If the "words" accessed by RHS are already accessed by
- LHS, this won't matter, but if RHS accesses "words" that LHS
- doesn't, then *SEPARATEP will be set to the compares that should
- take RHS's place. By "words" we mean contiguous bits that do not
- cross a an TYPE_ALIGN boundary of the accessed object's type.
-
We return the simplified tree or 0 if no optimization is possible. */
static tree
fold_truth_andor_1 (location_t loc, enum tree_code code, tree truth_type,
- tree lhs, tree rhs, tree *separatep)
+ tree lhs, tree rhs)
{
/* If this is the "or" of two comparisons, we can do something if
the comparisons are NE_EXPR. If this is the "and", we can do something
@@ -6751,28 +6354,9 @@ fold_truth_andor_1 (location_t loc, enum tree_code code,
tree truth_type,
convert EQ_EXPR to NE_EXPR so we need not reject the "wrong"
comparison for one-bit fields. */
- enum tree_code orig_code = code;
- enum tree_code wanted_code;
enum tree_code lcode, rcode;
tree ll_arg, lr_arg, rl_arg, rr_arg;
- tree ll_inner, lr_inner, rl_inner, rr_inner;
- HOST_WIDE_INT ll_bitsize, ll_bitpos, lr_bitsize, lr_bitpos;
- HOST_WIDE_INT rl_bitsize, rl_bitpos, rr_bitsize, rr_bitpos;
- HOST_WIDE_INT xll_bitpos, xlr_bitpos, xrl_bitpos, xrr_bitpos;
- HOST_WIDE_INT lnbitsize, lnbitpos, rnbitsize, rnbitpos;
- int ll_unsignedp, lr_unsignedp, rl_unsignedp, rr_unsignedp;
- int ll_reversep, lr_reversep, rl_reversep, rr_reversep;
- machine_mode ll_mode, lr_mode, rl_mode, rr_mode;
- scalar_int_mode lnmode, lnmode2, rnmode;
- tree ll_mask, lr_mask, rl_mask, rr_mask;
- tree ll_and_mask, lr_and_mask, rl_and_mask, rr_and_mask;
- tree l_const, r_const;
- tree lntype, rntype, result;
- HOST_WIDE_INT first_bit, end_bit;
- int volatilep;
- bool l_split_load;
-
- gcc_checking_assert (!separatep || !*separatep);
+ tree result;
/* Start by getting the comparison codes. Fail if anything is volatile.
If one operand is a BIT_AND_EXPR with the constant one, treat it as if
@@ -6800,116 +6384,7 @@ fold_truth_andor_1 (location_t loc, enum tree_code
code, tree truth_type,
if (TREE_CODE_CLASS (lcode) != tcc_comparison
|| TREE_CODE_CLASS (rcode) != tcc_comparison)
- {
- tree separate = NULL;
-
- /* Check for the possibility of merging component references.
- If any of our operands is another similar operation, recurse
- to try to merge individual operands, but avoiding double
- recursion: recurse to each leaf of LHS, and from there to
- each leaf of RHS, but don't bother recursing into LHS if RHS
- is neither a comparison nor a compound expr, nor into RHS if
- the LHS leaf isn't a comparison. In case of no successful
- merging, recursion depth is limited to the sum of the depths
- of LHS and RHS, and the non-recursing code below will run no
- more times than the product of the leaf counts of LHS and
- RHS. If there is a successful merge, we (recursively)
- further attempt to fold the result, so recursion depth and
- merge attempts are harder to compute. */
- if (TREE_CODE (lhs) == code && TREE_TYPE (lhs) == truth_type
- && (TREE_CODE_CLASS (rcode) == tcc_comparison
- || (TREE_CODE (rhs) == code && TREE_TYPE (rhs) == truth_type)))
- {
- if ((result = fold_truth_andor_1 (loc, code, truth_type,
- TREE_OPERAND (lhs, 1), rhs,
- separatep
- ? separatep
- : NULL)) != 0)
- {
- /* We have combined the latter part of LHS with RHS. If
- they were separate, the recursion already placed any
- remains of RHS in *SEPARATEP, otherwise they are all
- in RESULT, so we just have to prepend to result the
- former part of LHS. */
- result = fold_build2_loc (loc, code, truth_type,
- TREE_OPERAND (lhs, 0), result);
- return result;
- }
- if ((result = fold_truth_andor_1 (loc, code, truth_type,
- TREE_OPERAND (lhs, 0), rhs,
- separatep
- ? separatep
- : &separate)) != 0)
- {
- /* We have combined the former part of LHS with RHS. If
- they were separate, the recursive call will have
- placed remnants of RHS in *SEPARATEP. If they
- wereń't, they will be in SEPARATE instead. Append
- the latter part of LHS to the result, and then any
- remnants of RHS that we haven't passed on to the
- caller. */
- result = fold_build2_loc (loc, code, truth_type,
- result, TREE_OPERAND (lhs, 1));
- if (separate)
- result = fold_build2_loc (loc, code, truth_type,
- result, separate);
- return result;
- }
- }
- else if (TREE_CODE_CLASS (lcode) == tcc_comparison
- && TREE_CODE (rhs) == code && TREE_TYPE (rhs) == truth_type)
- {
- if ((result = fold_truth_andor_1 (loc, code, truth_type,
- lhs, TREE_OPERAND (rhs, 0),
- separatep
- ? &separate
- : NULL)) != 0)
- {
- /* We have combined LHS with the former part of RHS. If
- they were separate, have any remnants of RHS placed
- in separate, so that we can combine them with the
- latter part of RHS, and then send them back for the
- caller to handle. If they were adjacent, we can just
- append the latter part of RHS to the RESULT. */
- if (!separate)
- separate = TREE_OPERAND (rhs, 1);
- else
- separate = fold_build2_loc (loc, code, truth_type,
- separate, TREE_OPERAND (rhs, 1));
- if (separatep)
- *separatep = separate;
- else
- result = fold_build2_loc (loc, code, truth_type,
- result, separate);
- return result;
- }
- if ((result = fold_truth_andor_1 (loc, code, truth_type,
- lhs, TREE_OPERAND (rhs, 1),
- &separate)) != 0)
- {
- /* We have combined LHS with the latter part of RHS.
- They're definitely not adjacent, so we get the
- remains of RHS in SEPARATE, and then prepend the
- former part of RHS to it. If LHS and RHS were
- already separate to begin with, we leave the remnants
- of RHS for the caller to deal with, otherwise we
- append them to the RESULT. */
- if (!separate)
- separate = TREE_OPERAND (rhs, 0);
- else
- separate = fold_build2_loc (loc, code, truth_type,
- TREE_OPERAND (rhs, 0), separate);
- if (separatep)
- *separatep = separate;
- else
- result = fold_build2_loc (loc, code, truth_type,
- result, separate);
- return result;
- }
- }
-
- return 0;
- }
+ return 0;
ll_arg = TREE_OPERAND (lhs, 0);
lr_arg = TREE_OPERAND (lhs, 1);
@@ -6976,508 +6451,7 @@ fold_truth_andor_1 (location_t loc, enum tree_code
code, tree truth_type,
build_int_cst (TREE_TYPE (ll_arg), 0));
}
- /* See if the comparisons can be merged. Then get all the parameters for
- each side. */
-
- if ((lcode != EQ_EXPR && lcode != NE_EXPR)
- || (rcode != EQ_EXPR && rcode != NE_EXPR))
- return 0;
-
- ll_reversep = lr_reversep = rl_reversep = rr_reversep = 0;
- volatilep = 0;
- int l_xor = prepare_xor (ll_arg, &lr_arg);
- ll_inner = decode_field_reference (loc, &ll_arg,
- &ll_bitsize, &ll_bitpos, &ll_mode,
- &ll_unsignedp, &ll_reversep, &volatilep,
- &ll_mask, &ll_and_mask, l_xor);
- lr_inner = decode_field_reference (loc, &lr_arg,
- &lr_bitsize, &lr_bitpos, &lr_mode,
- &lr_unsignedp, &lr_reversep, &volatilep,
- &lr_mask, &lr_and_mask, 2 * l_xor);
- int r_xor = prepare_xor (rl_arg, &rr_arg);
- rl_inner = decode_field_reference (loc, &rl_arg,
- &rl_bitsize, &rl_bitpos, &rl_mode,
- &rl_unsignedp, &rl_reversep, &volatilep,
- &rl_mask, &rl_and_mask, r_xor);
- rr_inner = decode_field_reference (loc, &rr_arg,
- &rr_bitsize, &rr_bitpos, &rr_mode,
- &rr_unsignedp, &rr_reversep, &volatilep,
- &rr_mask, &rr_and_mask, 2 * r_xor);
-
- /* It must be true that the inner operation on the lhs of each
- comparison must be the same if we are to be able to do anything.
- Then see if we have constants. If not, the same must be true for
- the rhs's. */
- if (volatilep
- || ll_reversep != rl_reversep
- || ll_inner == 0 || rl_inner == 0
- || ! operand_equal_p (ll_inner, rl_inner, 0))
- return 0;
-
- if (TREE_CODE (lr_arg) == INTEGER_CST
- && TREE_CODE (rr_arg) == INTEGER_CST)
- {
- l_const = lr_arg, r_const = rr_arg;
- lr_reversep = ll_reversep;
- }
- else if (lr_reversep != rr_reversep
- || lr_inner == 0 || rr_inner == 0
- || ! operand_equal_p (lr_inner, rr_inner, 0))
- return 0;
- else
- l_const = r_const = 0;
-
- /* If either comparison code is not correct for our logical operation,
- fail. However, we can convert a one-bit comparison against zero into
- the opposite comparison against that bit being set in the field. */
-
- wanted_code = (code == TRUTH_AND_EXPR ? EQ_EXPR : NE_EXPR);
- if (lcode != wanted_code)
- {
- if (l_const && integer_zerop (l_const) && integer_pow2p (ll_mask))
- {
- /* Make the left operand unsigned, since we are only interested
- in the value of one bit. Otherwise we are doing the wrong
- thing below. */
- ll_unsignedp = 1;
- l_const = ll_mask;
- }
- else
- return 0;
- }
-
- /* This is analogous to the code for l_const above. */
- if (rcode != wanted_code)
- {
- if (r_const && integer_zerop (r_const) && integer_pow2p (rl_mask))
- {
- rl_unsignedp = 1;
- r_const = rl_mask;
- }
- else
- return 0;
- }
-
- /* This will be bumped to 2 if any of the field pairs crosses an
- alignment boundary, so the merged compare has to be done in two
- parts. */
- int parts = 1;
- /* Set to true if the second combined compare should come first,
- e.g., because the second original compare accesses a word that
- the first one doesn't, and the combined compares access those in
- cmp[0]. */
- bool first1 = false;
- /* Set to true if the first original compare is not the one being
- split. */
- bool maybe_separate = false;
-
- /* The following 2-dimensional arrays use the first index to
- identify left(0)- vs right(1)-hand compare operands, and the
- second one to identify merged compare parts. */
- /* The memory loads or constants to be compared. */
- tree ld_arg[2][2];
- /* The first bit of the corresponding inner object that the
- corresponding LD_ARG covers. */
- HOST_WIDE_INT bitpos[2][2];
- /* The bit count starting at BITPOS that the corresponding LD_ARG
- covers. */
- HOST_WIDE_INT bitsiz[2][2];
- /* The number of bits by which LD_ARG has already been shifted
- right, WRT mask. */
- HOST_WIDE_INT shifted[2][2];
- /* The number of bits by which both LD_ARG and MASK need shifting to
- bring its least-significant bit to bit zero. */
- HOST_WIDE_INT toshift[2][2];
- /* An additional mask to be applied to LD_ARG, to remove any bits
- that may have been loaded for use in another compare, but that
- don't belong in the corresponding compare. */
- tree xmask[2][2] = {};
-
- /* The combined compare or compares. */
- tree cmp[2];
-
- /* Consider we're comparing two non-contiguous fields of packed
- structs, both aligned at 32-bit boundaries:
-
- ll_arg: an 8-bit field at offset 0
- lr_arg: a 16-bit field at offset 2
-
- rl_arg: an 8-bit field at offset 1
- rr_arg: a 16-bit field at offset 3
-
- We'll have r_split_load, because rr_arg straddles across an
- alignment boundary.
-
- We'll want to have:
-
- bitpos = { { 0, 0 }, { 0, 32 } }
- bitsiz = { { 32, 32 }, { 32, 8 } }
-
- And, for little-endian:
-
- shifted = { { 0, 0 }, { 0, 32 } }
- toshift = { { 0, 24 }, { 0, 0 } }
-
- Or, for big-endian:
-
- shifted = { { 0, 0 }, { 8, 0 } }
- toshift = { { 8, 0 }, { 0, 0 } }
- */
-
- /* See if we can find a mode that contains both fields being compared on
- the left. If we can't, fail. Otherwise, update all constants and masks
- to be relative to a field of that size. */
- first_bit = MIN (ll_bitpos, rl_bitpos);
- end_bit = MAX (ll_bitpos + ll_bitsize, rl_bitpos + rl_bitsize);
- if (!get_best_mode (end_bit - first_bit, first_bit, 0, 0,
- TYPE_ALIGN (TREE_TYPE (ll_inner)), BITS_PER_WORD,
- volatilep, &lnmode))
- {
- /* Consider the possibility of recombining loads if any of the
- fields straddles across an alignment boundary, so that either
- part can be loaded along with the other field. */
- HOST_WIDE_INT align = TYPE_ALIGN (TREE_TYPE (ll_inner));
- HOST_WIDE_INT boundary = compute_split_boundary_from_align
- (align, ll_bitpos, ll_bitsize, rl_bitpos, rl_bitsize);
-
- if (boundary < 0
- || !get_best_mode (boundary - first_bit, first_bit, 0, 0,
- align, BITS_PER_WORD, volatilep, &lnmode)
- || !get_best_mode (end_bit - boundary, boundary, 0, 0,
- align, BITS_PER_WORD, volatilep, &lnmode2))
- return 0;
-
- l_split_load = true;
- parts = 2;
- if (ll_bitpos >= boundary)
- maybe_separate = first1 = true;
- else if (ll_bitpos + ll_bitsize <= boundary)
- maybe_separate = true;
- }
- else
- l_split_load = false;
-
- lnbitsize = GET_MODE_BITSIZE (lnmode);
- lnbitpos = first_bit & ~ (lnbitsize - 1);
- if (l_split_load)
- lnbitsize += GET_MODE_BITSIZE (lnmode2);
- lntype = lang_hooks.types.type_for_size (lnbitsize, 1);
- if (!lntype)
- {
- gcc_checking_assert (l_split_load);
- lntype = build_nonstandard_integer_type (lnbitsize, 1);
- }
- xll_bitpos = ll_bitpos - lnbitpos, xrl_bitpos = rl_bitpos - lnbitpos;
-
- if (ll_reversep ? !BYTES_BIG_ENDIAN : BYTES_BIG_ENDIAN)
- {
- xll_bitpos = lnbitsize - xll_bitpos - ll_bitsize;
- xrl_bitpos = lnbitsize - xrl_bitpos - rl_bitsize;
- }
-
- ll_mask = const_binop (LSHIFT_EXPR, fold_convert_loc (loc, lntype, ll_mask),
- size_int (xll_bitpos));
- rl_mask = const_binop (LSHIFT_EXPR, fold_convert_loc (loc, lntype, rl_mask),
- size_int (xrl_bitpos));
- if (ll_mask == NULL_TREE || rl_mask == NULL_TREE)
- return 0;
-
- if (l_const)
- {
- l_const = fold_convert_loc (loc, lntype, l_const);
- l_const = unextend (l_const, ll_bitsize, ll_unsignedp, ll_and_mask);
- l_const = const_binop (LSHIFT_EXPR, l_const, size_int (xll_bitpos));
- if (l_const == NULL_TREE)
- return 0;
- if (! integer_zerop (const_binop (BIT_AND_EXPR, l_const,
- fold_build1_loc (loc, BIT_NOT_EXPR,
- lntype, ll_mask))))
- {
- warning (0, "comparison is always %d", wanted_code == NE_EXPR);
-
- return constant_boolean_node (wanted_code == NE_EXPR, truth_type);
- }
- }
- if (r_const)
- {
- r_const = fold_convert_loc (loc, lntype, r_const);
- r_const = unextend (r_const, rl_bitsize, rl_unsignedp, rl_and_mask);
- r_const = const_binop (LSHIFT_EXPR, r_const, size_int (xrl_bitpos));
- if (r_const == NULL_TREE)
- return 0;
- if (! integer_zerop (const_binop (BIT_AND_EXPR, r_const,
- fold_build1_loc (loc, BIT_NOT_EXPR,
- lntype, rl_mask))))
- {
- warning (0, "comparison is always %d", wanted_code == NE_EXPR);
-
- return constant_boolean_node (wanted_code == NE_EXPR, truth_type);
- }
- }
-
- /* If the right sides are not constant, do the same for it. Also,
- disallow this optimization if a size, signedness or storage order
- mismatch occurs between the left and right sides. */
- if (l_const == 0)
- {
- if (ll_bitsize != lr_bitsize || rl_bitsize != rr_bitsize
- || ll_unsignedp != lr_unsignedp || rl_unsignedp != rr_unsignedp
- || ll_reversep != lr_reversep
- /* Make sure the two fields on the right
- correspond to the left without being swapped. */
- || ll_bitpos - rl_bitpos != lr_bitpos - rr_bitpos
- || lnbitpos < 0)
- return 0;
-
- bool r_split_load;
- scalar_int_mode rnmode2;
-
- first_bit = MIN (lr_bitpos, rr_bitpos);
- end_bit = MAX (lr_bitpos + lr_bitsize, rr_bitpos + rr_bitsize);
- if (!get_best_mode (end_bit - first_bit, first_bit, 0, 0,
- TYPE_ALIGN (TREE_TYPE (lr_inner)), BITS_PER_WORD,
- volatilep, &rnmode))
- {
- /* Consider the possibility of recombining loads if any of the
- fields straddles across an alignment boundary, so that either
- part can be loaded along with the other field. */
- HOST_WIDE_INT align = TYPE_ALIGN (TREE_TYPE (lr_inner));
- HOST_WIDE_INT boundary = compute_split_boundary_from_align
- (align, lr_bitpos, lr_bitsize, rr_bitpos, rr_bitsize);
-
- if (boundary < 0
- /* If we're to split both, make sure the split point is
- the same. */
- || (l_split_load
- && (boundary - lr_bitpos
- != (lnbitpos + GET_MODE_BITSIZE (lnmode)) - ll_bitpos))
- || !get_best_mode (boundary - first_bit, first_bit, 0, 0,
- align, BITS_PER_WORD, volatilep, &rnmode)
- || !get_best_mode (end_bit - boundary, boundary, 0, 0,
- align, BITS_PER_WORD, volatilep, &rnmode2))
- return 0;
-
- r_split_load = true;
- parts = 2;
- if (lr_bitpos >= boundary)
- maybe_separate = first1 = true;
- else if (lr_bitpos + lr_bitsize <= boundary)
- maybe_separate = true;
- }
- else
- r_split_load = false;
-
- rnbitsize = GET_MODE_BITSIZE (rnmode);
- rnbitpos = first_bit & ~ (rnbitsize - 1);
- if (r_split_load)
- rnbitsize += GET_MODE_BITSIZE (rnmode2);
- rntype = lang_hooks.types.type_for_size (rnbitsize, 1);
- if (!rntype)
- {
- gcc_checking_assert (r_split_load);
- rntype = build_nonstandard_integer_type (rnbitsize, 1);
- }
- xlr_bitpos = lr_bitpos - rnbitpos, xrr_bitpos = rr_bitpos - rnbitpos;
-
- if (lr_reversep ? !BYTES_BIG_ENDIAN : BYTES_BIG_ENDIAN)
- {
- xlr_bitpos = rnbitsize - xlr_bitpos - lr_bitsize;
- xrr_bitpos = rnbitsize - xrr_bitpos - rr_bitsize;
- }
-
- lr_mask = const_binop (LSHIFT_EXPR, fold_convert_loc (loc,
- rntype, lr_mask),
- size_int (xlr_bitpos));
- rr_mask = const_binop (LSHIFT_EXPR, fold_convert_loc (loc,
- rntype, rr_mask),
- size_int (xrr_bitpos));
- if (lr_mask == NULL_TREE || rr_mask == NULL_TREE)
- return 0;
-
- lr_mask = const_binop (BIT_IOR_EXPR, lr_mask, rr_mask);
-
- toshift[1][0] = MIN (xlr_bitpos, xrr_bitpos);
- shifted[1][0] = 0;
-
- if (!r_split_load)
- {
- bitpos[1][0] = rnbitpos;
- bitsiz[1][0] = rnbitsize;
- ld_arg[1][0] = make_bit_field_ref (loc, lr_inner, lr_arg,
- rntype, rnbitsize, rnbitpos,
- lr_unsignedp || rr_unsignedp,
- lr_reversep);
- }
-
- if (parts > 1)
- {
- if (r_split_load)
- build_split_load (ld_arg[1], bitpos[1], bitsiz[1], toshift[1],
- shifted[1], loc, lr_inner, lr_arg,
- rnmode, rnmode2, rnbitpos, lr_reversep);
- else
- reuse_split_load (ld_arg[1], bitpos[1], bitsiz[1], toshift[1],
- shifted[1], xmask[1],
- lnbitpos + GET_MODE_BITSIZE (lnmode)
- - ll_bitpos + lr_bitpos, lr_reversep);
- }
- }
- else
- {
- /* Handle the case of comparisons with constants. If there is
- something in common between the masks, those bits of the
- constants must be the same. If not, the condition is always
- false. Test for this to avoid generating incorrect code
- below. */
- result = const_binop (BIT_AND_EXPR, ll_mask, rl_mask);
- if (! integer_zerop (result)
- && simple_cst_equal (const_binop (BIT_AND_EXPR,
- result, l_const),
- const_binop (BIT_AND_EXPR,
- result, r_const)) != 1)
- {
- if (wanted_code == NE_EXPR)
- {
- warning (0,
- "%<or%> of unmatched not-equal tests"
- " is always 1");
- return constant_boolean_node (true, truth_type);
- }
- else
- {
- warning (0,
- "%<and%> of mutually exclusive equal-tests"
- " is always 0");
- return constant_boolean_node (false, truth_type);
- }
- }
-
- if (lnbitpos < 0)
- return 0;
-
- /* The constants are combined so as to line up with the loaded
- field, so use the same parameters. */
- ld_arg[1][0] = const_binop (BIT_IOR_EXPR, l_const, r_const);
- toshift[1][0] = MIN (xll_bitpos, xrl_bitpos);
- shifted[1][0] = 0;
- bitpos[1][0] = lnbitpos;
- bitsiz[1][0] = lnbitsize;
-
- if (parts > 1)
- reuse_split_load (ld_arg[1], bitpos[1], bitsiz[1], toshift[1],
- shifted[1], xmask[1],
- lnbitpos + GET_MODE_BITSIZE (lnmode),
- lr_reversep);
-
- lr_mask = build_int_cst_type (TREE_TYPE (ld_arg[1][0]), -1);
-
- /* If the compiler thinks this is used uninitialized below, it's
- because it can't realize that parts can only be 2 when
- comparing wiht constants if l_split_load is also true. This
- just silences the warning. */
- rnbitpos = 0;
- }
-
- ll_mask = const_binop (BIT_IOR_EXPR, ll_mask, rl_mask);
- toshift[0][0] = MIN (xll_bitpos, xrl_bitpos);
- shifted[0][0] = 0;
-
- if (!l_split_load)
- {
- bitpos[0][0] = lnbitpos;
- bitsiz[0][0] = lnbitsize;
- ld_arg[0][0] = make_bit_field_ref (loc, ll_inner, ll_arg,
- lntype, lnbitsize, lnbitpos,
- ll_unsignedp || rl_unsignedp,
- ll_reversep);
- }
-
- if (parts > 1)
- {
- if (l_split_load)
- build_split_load (ld_arg[0], bitpos[0], bitsiz[0], toshift[0],
- shifted[0], loc, ll_inner, ll_arg,
- lnmode, lnmode2, lnbitpos, ll_reversep);
- else
- reuse_split_load (ld_arg[0], bitpos[0], bitsiz[0], toshift[0],
- shifted[0], xmask[0],
- rnbitpos + GET_MODE_BITSIZE (rnmode)
- - lr_bitpos + ll_bitpos, ll_reversep);
- }
-
- for (int i = 0; i < parts; i++)
- {
- tree op[2] = { ld_arg[0][i], ld_arg[1][i] };
- tree mask[2] = { ll_mask, lr_mask };
-
- for (int j = 0; j < 2; j++)
- {
- /* Mask out the bits belonging to the other part. */
- if (xmask[j][i])
- mask[j] = const_binop (BIT_AND_EXPR, mask[j], xmask[j][i]);
-
- if (shifted[j][i])
- {
- tree shiftsz = bitsize_int (shifted[j][i]);
- mask[j] = const_binop (RSHIFT_EXPR, mask[j], shiftsz);
- }
- mask[j] = fold_convert_loc (loc, TREE_TYPE (op[j]), mask[j]);
- }
-
- HOST_WIDE_INT shift = (toshift[0][i] - toshift[1][i]);
-
- if (shift)
- {
- int j;
- if (shift > 0)
- j = 0;
- else
- {
- j = 1;
- shift = -shift;
- }
-
- tree shiftsz = bitsize_int (shift);
- op[j] = fold_build2_loc (loc, RSHIFT_EXPR, TREE_TYPE (op[j]),
- op[j], shiftsz);
- mask[j] = const_binop (RSHIFT_EXPR, mask[j], shiftsz);
- }
-
- /* Convert to the smaller type before masking out unwanted
- bits. */
- tree type = TREE_TYPE (op[0]);
- if (type != TREE_TYPE (op[1]))
- {
- int j = (TYPE_PRECISION (type)
- < TYPE_PRECISION (TREE_TYPE (op[1])));
- if (!j)
- type = TREE_TYPE (op[1]);
- op[j] = fold_convert_loc (loc, type, op[j]);
- mask[j] = fold_convert_loc (loc, type, mask[j]);
- }
-
- for (int j = 0; j < 2; j++)
- if (! integer_all_onesp (mask[j]))
- op[j] = build2_loc (loc, BIT_AND_EXPR, type,
- op[j], mask[j]);
-
- cmp[i] = build2_loc (loc, wanted_code, truth_type, op[0], op[1]);
- }
-
- if (first1)
- std::swap (cmp[0], cmp[1]);
-
- if (parts == 1)
- result = cmp[0];
- else if (!separatep || !maybe_separate)
- result = build2_loc (loc, orig_code, truth_type, cmp[0], cmp[1]);
- else
- {
- result = cmp[0];
- *separatep = cmp[1];
- }
-
- return result;
+ return 0;
}
/* T is an integer expression that is being multiplied, divided, or taken a
@@ -10546,7 +9520,15 @@ fold_truth_andor (location_t loc, enum tree_code code,
tree type,
return fold_build2_loc (loc, code, type, arg0, tem);
}
- if ((tem = fold_truth_andor_1 (loc, code, type, arg0, arg1, NULL)) != 0)
+ /* Check for the possibility of merging component references. If our
+ lhs is another similar operation, try to merge its rhs with our
+ rhs. Then try to merge our lhs and rhs. */
+ if (TREE_CODE (arg0) == code
+ && (tem = fold_truth_andor_1 (loc, code, type,
+ TREE_OPERAND (arg0, 1), arg1)) != 0)
+ return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), tem);
+
+ if ((tem = fold_truth_andor_1 (loc, code, type, arg0, arg1)) != 0)
return tem;
bool logical_op_non_short_circuit = LOGICAL_OP_NON_SHORT_CIRCUIT;
diff --git a/gcc/gimple-fold.cc b/gcc/gimple-fold.cc
index 942de7720fd2..64426bd76977 100644
--- a/gcc/gimple-fold.cc
+++ b/gcc/gimple-fold.cc
@@ -70,6 +70,12 @@ along with GCC; see the file COPYING3. If not see
#include "internal-fn.h"
#include "gimple-range.h"
+/* ??? Move this to some header, it's defined in fold-const.c. */
+extern tree
+make_bit_field_ref (location_t loc, tree inner, tree orig_inner, tree type,
+ HOST_WIDE_INT bitsize, poly_int64 bitpos,
+ int unsignedp, int reversep);
+
enum strlen_range_kind {
/* Compute the exact constant string length. */
SRK_STRLEN,
@@ -7384,7 +7390,1143 @@ maybe_fold_comparisons_from_match_pd (tree type, enum
tree_code code,
return NULL_TREE;
}
+
+/* Return TRUE if expression STMT is suitable for replacement. ???
+ Same as ssa_is_replaceable_p, except that we don't insist it has a
+ single use. */
+
+bool
+ssa_is_substitutable_p (gimple *stmt)
+{
+#if 0
+ use_operand_p use_p;
+#endif
+ tree def;
+#if 0
+ gimple *use_stmt;
+#endif
+
+ /* Only consider modify stmts. */
+ if (!is_gimple_assign (stmt))
+ return false;
+
+ /* If the statement may throw an exception, it cannot be replaced. */
+ if (stmt_could_throw_p (cfun, stmt))
+ return false;
+
+ /* Punt if there is more than 1 def. */
+ def = SINGLE_SSA_TREE_OPERAND (stmt, SSA_OP_DEF);
+ if (!def)
+ return false;
+
+#if 0
+ /* Only consider definitions which have a single use. */
+ if (!single_imm_use (def, &use_p, &use_stmt))
+ return false;
+
+ /* Used in this block, but at the TOP of the block, not the end. */
+ if (gimple_code (use_stmt) == GIMPLE_PHI)
+ return false;
+#endif
+
+ /* There must be no VDEFs. */
+ if (gimple_vdef (stmt))
+ return false;
+
+ /* Float expressions must go through memory if float-store is on. */
+ if (flag_float_store
+ && FLOAT_TYPE_P (TREE_TYPE (def)))
+ return false;
+
+ /* An assignment with a register variable on the RHS is not
+ replaceable. */
+ if (gimple_assign_rhs_code (stmt) == VAR_DECL
+ && DECL_HARD_REGISTER (gimple_assign_rhs1 (stmt)))
+ return false;
+
+ /* No function calls can be replaced. */
+ if (is_gimple_call (stmt))
+ return false;
+
+ /* Leave any stmt with volatile operands alone as well. */
+ if (gimple_has_volatile_ops (stmt))
+ return false;
+
+ return true;
+}
+
+/* Follow substitutable SSA DEFs for *NAME, including type casts,
+ adjusting *NAME to the single rhs or the type cast operand along
+ the way. Return the target type of the earliest type cast
+ found. */
+
+static tree
+is_cast_p (tree *name)
+{
+ tree type = 0;
+
+ while (TREE_CODE (*name) == SSA_NAME
+ && !SSA_NAME_IS_DEFAULT_DEF (*name))
+ {
+ gimple *def = SSA_NAME_DEF_STMT (*name);
+
+ if (!ssa_is_substitutable_p (def))
+ break;
+
+ if (gimple_num_ops (def) != 2)
+ break;
+
+ if (get_gimple_rhs_class (gimple_expr_code (def))
+ == GIMPLE_SINGLE_RHS)
+ {
+ *name = gimple_assign_rhs1 (def);
+ continue;
+ }
+
+ if (!gimple_assign_cast_p (def))
+ break;
+
+ if (!type)
+ type = TREE_TYPE (*name);
+ *name = gimple_assign_rhs1 (def);
+ }
+
+ return type;
+}
+
+/* Follow substitutable SSA DEFs for *NAME. If we find it is assigned
+ a CODE binary expr, return the second operand, and set *NAME to the
+ first operand. */
+
+static tree
+is_binop_p (enum tree_code code, tree *name)
+{
+ while (TREE_CODE (*name) == SSA_NAME
+ && !SSA_NAME_IS_DEFAULT_DEF (*name))
+ {
+ gimple *def = SSA_NAME_DEF_STMT (*name);
+
+ if (!ssa_is_substitutable_p (def))
+ return 0;
+
+ switch (gimple_num_ops (def))
+ {
+ default:
+ return 0;
+
+ case 2:
+ if (get_gimple_rhs_class (gimple_expr_code (def))
+ == GIMPLE_SINGLE_RHS)
+ {
+ *name = gimple_assign_rhs1 (def);
+ continue;
+ }
+ return 0;
+
+ case 3:
+ ;
+ }
+
+ if (gimple_assign_rhs_code (def) != code)
+ return 0;
+
+ *name = gimple_assign_rhs1 (def);
+ return gimple_assign_rhs2 (def);
+ }
+
+ return 0;
+}
+
+/* If *R_ARG is a constant zero, and L_ARG is a possibly masked
+ BIT_XOR_EXPR, return 1 and set *r_arg to l_arg.
+ Otherwise, return 0.
+
+ The returned value should be passed to decode_field_reference for it
+ to handle l_arg, and then doubled for r_arg. */
+
+static int
+prepare_xor (tree l_arg, tree *r_arg)
+{
+ int ret = 0;
+
+ if (!integer_zerop (*r_arg))
+ return ret;
+
+ tree exp = l_arg;
+
+ if (tree and_mask = is_binop_p (BIT_AND_EXPR, &exp))
+ {
+ if (TREE_CODE (and_mask) != INTEGER_CST)
+ return ret;
+ }
+
+ if (is_binop_p (BIT_XOR_EXPR, &exp))
+ {
+ *r_arg = l_arg;
+ return 1;
+ }
+
+ return ret;
+}
+
+/* Subroutine for fold_truth_andor_1: decode a field reference.
+
+ If EXP is a comparison reference, we return the innermost reference.
+
+ *PBITSIZE is set to the number of bits in the reference, *PBITPOS is
+ set to the starting bit number.
+
+ If the innermost field can be completely contained in a mode-sized
+ unit, *PMODE is set to that mode. Otherwise, it is set to VOIDmode.
+
+ *PVOLATILEP is set to 1 if the any expression encountered is volatile;
+ otherwise it is not changed.
+
+ *PUNSIGNEDP is set to the signedness of the field.
+
+ *PREVERSEP is set to the storage order of the field.
+
+ *PMASK is set to the mask used. This is either contained in a
+ BIT_AND_EXPR or derived from the width of the field.
+
+ *PAND_MASK is set to the mask found in a BIT_AND_EXPR, if any.
+
+ XOR_WHICH is 1 or 2 if EXP was found to be a (possibly masked)
+ BIT_XOR_EXPR compared with zero. We're to take the first or second
+ operand thereof if so. It should be zero otherwise.
+
+ Return 0 if this is not a component reference or is one that we can't
+ do anything with. */
+
+static tree
+decode_field_reference (location_t loc, tree *exp_, HOST_WIDE_INT *pbitsize,
+ HOST_WIDE_INT *pbitpos, machine_mode *pmode,
+ int *punsignedp, int *preversep, int *pvolatilep,
+ tree *pmask, tree *pand_mask, int xor_which)
+{
+ tree exp = *exp_;
+ tree outer_type = 0;
+ tree and_mask = 0;
+ tree mask, inner, offset;
+ tree unsigned_type;
+ unsigned int precision;
+ HOST_WIDE_INT shiftrt = 0;
+
+ /* All the optimizations using this function assume integer fields.
+ There are problems with FP fields since the type_for_size call
+ below can fail for, e.g., XFmode. */
+ if (! INTEGRAL_TYPE_P (TREE_TYPE (exp)))
+ return 0;
+
+ /* We are interested in the bare arrangement of bits, so strip everything
+ that doesn't affect the machine mode. However, record the type of the
+ outermost expression if it may matter below. */
+ outer_type = is_cast_p (&exp);
+
+ if ((and_mask = is_binop_p (BIT_AND_EXPR, &exp)))
+ {
+ if (TREE_CODE (and_mask) != INTEGER_CST)
+ return 0;
+ }
+
+ if (xor_which)
+ {
+ tree op2 = is_binop_p (BIT_XOR_EXPR, &exp);
+ gcc_checking_assert (op2);
+ if (xor_which > 1)
+ exp = op2;
+ }
+
+ if (tree t = is_cast_p (&exp))
+ if (!outer_type)
+ outer_type = t;
+
+ if (tree shift = is_binop_p (RSHIFT_EXPR, &exp))
+ {
+ if (TREE_CODE (shift) != INTEGER_CST || !tree_fits_shwi_p (shift))
+ return 0;
+ shiftrt = tree_to_shwi (shift);
+ if (shiftrt <= 0)
+ return 0;
+ }
+
+ if (tree t = is_cast_p (&exp))
+ if (!outer_type)
+ outer_type = t;
+
+ poly_int64 poly_bitsize, poly_bitpos;
+ inner = get_inner_reference (exp, &poly_bitsize, &poly_bitpos, &offset,
+ pmode, punsignedp, preversep, pvolatilep);
+
+ if ((inner == exp && and_mask == 0)
+ || !poly_bitsize.is_constant (pbitsize)
+ || !poly_bitpos.is_constant (pbitpos)
+ || *pbitsize <= shiftrt
+ || offset != 0
+ || TREE_CODE (inner) == PLACEHOLDER_EXPR
+ /* Reject out-of-bound accesses (PR79731). */
+ || (! AGGREGATE_TYPE_P (TREE_TYPE (inner))
+ && compare_tree_int (TYPE_SIZE (TREE_TYPE (inner)),
+ *pbitpos + *pbitsize) < 0))
+ return NULL_TREE;
+
+ if (shiftrt)
+ {
+ if (!*preversep ? !BYTES_BIG_ENDIAN : BYTES_BIG_ENDIAN)
+ *pbitpos += shiftrt;
+ *pbitsize -= shiftrt;
+ }
+
+ if (outer_type && *pbitsize > TYPE_PRECISION (outer_type))
+ {
+ HOST_WIDE_INT excess = *pbitsize - TYPE_PRECISION (outer_type);
+ if (*preversep ? !BYTES_BIG_ENDIAN : BYTES_BIG_ENDIAN)
+ *pbitpos += excess;
+ *pbitsize -= excess;
+ }
+
+ unsigned_type = lang_hooks.types.type_for_size (*pbitsize, 1);
+ if (unsigned_type == NULL_TREE)
+ return NULL_TREE;
+
+ *exp_ = exp;
+
+ /* If the number of bits in the reference is the same as the bitsize of
+ the outer type, then the outer type gives the signedness. Otherwise
+ (in case of a small bitfield) the signedness is unchanged. */
+ if (outer_type && *pbitsize == TYPE_PRECISION (outer_type))
+ *punsignedp = TYPE_UNSIGNED (outer_type);
+
+ /* Compute the mask to access the bitfield. */
+ precision = TYPE_PRECISION (unsigned_type);
+
+ mask = build_int_cst_type (unsigned_type, -1);
+
+ mask = int_const_binop (LSHIFT_EXPR, mask, size_int (precision - *pbitsize));
+ mask = int_const_binop (RSHIFT_EXPR, mask, size_int (precision - *pbitsize));
+
+ /* Merge it with the mask we found in the BIT_AND_EXPR, if any. */
+ if (and_mask != 0)
+ mask = fold_build2_loc (loc, BIT_AND_EXPR, unsigned_type,
+ fold_convert_loc (loc, unsigned_type, and_mask), mask);
+
+ *pmask = mask;
+ *pand_mask = and_mask;
+ return inner;
+}
+
+/* Subroutine for fold_truth_andor_1: C is an INTEGER_CST interpreted as a P
+ bit value. Arrange things so the extra bits will be set to zero if and
+ only if C is signed-extended to its full width. If MASK is nonzero,
+ it is an INTEGER_CST that should be AND'ed with the extra bits. */
+
+static tree
+unextend (tree c, int p, int unsignedp, tree mask)
+{
+ tree type = TREE_TYPE (c);
+ int modesize = GET_MODE_BITSIZE (SCALAR_INT_TYPE_MODE (type));
+ tree temp;
+
+ if (p == modesize || unsignedp)
+ return c;
+
+ /* We work by getting just the sign bit into the low-order bit, then
+ into the high-order bit, then sign-extend. We then XOR that value
+ with C. */
+ temp = build_int_cst (TREE_TYPE (c),
+ wi::extract_uhwi (wi::to_wide (c), p - 1, 1));
+
+ /* We must use a signed type in order to get an arithmetic right shift.
+ However, we must also avoid introducing accidental overflows, so that
+ a subsequent call to integer_zerop will work. Hence we must
+ do the type conversion here. At this point, the constant is either
+ zero or one, and the conversion to a signed type can never overflow.
+ We could get an overflow if this conversion is done anywhere else. */
+ if (TYPE_UNSIGNED (type))
+ temp = fold_convert (signed_type_for (type), temp);
+
+ temp = int_const_binop (LSHIFT_EXPR, temp, size_int (modesize - 1));
+ temp = int_const_binop (RSHIFT_EXPR, temp, size_int (modesize - p - 1));
+ if (mask != 0)
+ temp = int_const_binop (BIT_AND_EXPR, temp,
+ fold_convert (TREE_TYPE (c), mask));
+ /* If necessary, convert the type back to match the type of C. */
+ if (TYPE_UNSIGNED (type))
+ temp = fold_convert (type, temp);
+
+ return fold_convert (type, int_const_binop (BIT_XOR_EXPR, c, temp));
+}
+
+/* Return the one bitpos within bit extents L or R that is at an
+ ALIGN-bit alignment boundary, or -1 if there is more than one such
+ boundary, if there isn't any, or if there is any such boundary
+ between the extents. L and R are given by bitpos and bitsize. If
+ it doesn't return -1, there are two consecutive ALIGN-bit words
+ that contain both extents, and at least one of the extents
+ straddles across the returned alignment boundary. */
+
+static inline HOST_WIDE_INT
+compute_split_boundary_from_align (HOST_WIDE_INT align,
+ HOST_WIDE_INT l_bitpos,
+ HOST_WIDE_INT l_bitsize,
+ HOST_WIDE_INT r_bitpos,
+ HOST_WIDE_INT r_bitsize)
+{
+ HOST_WIDE_INT amask = ~(align - 1);
+
+ HOST_WIDE_INT first_bit = MIN (l_bitpos, r_bitpos);
+ HOST_WIDE_INT end_bit = MAX (l_bitpos + l_bitsize, r_bitpos + r_bitsize);
+
+ HOST_WIDE_INT boundary = (end_bit - 1) & amask;
+
+ /* Make sure we're crossing no more than one alignment boundary.
+
+ ??? We don't have logic to recombine loads of two adjacent
+ fields that each crosses a different alignment boundary, so
+ as to load the middle word only once, if other words can't be
+ otherwise recombined. */
+ if (boundary - first_bit > align)
+ return -1;
+
+ HOST_WIDE_INT l_start_word = l_bitpos & amask;
+ HOST_WIDE_INT l_end_word = (l_bitpos + l_bitsize - 1) & amask;
+
+ HOST_WIDE_INT r_start_word = r_bitpos & amask;
+ HOST_WIDE_INT r_end_word = (r_bitpos + r_bitsize - 1) & amask;
+
+ /* If neither field straddles across an alignment boundary, it's no
+ use to even try to merge them. */
+ if (l_start_word == l_end_word && r_start_word == r_end_word)
+ return -1;
+
+ return boundary;
+}
+
+/* Initialize ln_arg[0] and ln_arg[1] to a pair of newly-created (at
+ LOC) loads from INNER (from ORIG_INNER), of modes MODE and MODE2,
+ respectively, starting at BIT_POS, using reversed endianness if
+ REVERSEP. Also initialize BITPOS (the starting position of each
+ part into INNER), BITSIZ (the bit count starting at BITPOS),
+ TOSHIFT[1] (the amount by which the part and its mask are to be
+ shifted right to bring its least-significant bit to bit zero) and
+ SHIFTED (the amount by which the part, by separate loading, has
+ already been shifted right, but that the mask needs shifting to
+ match). */
+
+static inline void
+build_split_load (tree /* out */ ln_arg[2],
+ HOST_WIDE_INT /* out */ bitpos[2],
+ HOST_WIDE_INT /* out */ bitsiz[2],
+ HOST_WIDE_INT /* in[0] out[0..1] */ toshift[2],
+ HOST_WIDE_INT /* out */ shifted[2],
+ location_t loc, tree inner, tree orig_inner,
+ scalar_int_mode mode, scalar_int_mode mode2,
+ HOST_WIDE_INT bit_pos, bool reversep)
+{
+ bitsiz[0] = GET_MODE_BITSIZE (mode);
+ bitsiz[1] = GET_MODE_BITSIZE (mode2);
+
+ for (int i = 0; i < 2; i++)
+ {
+ tree type = lang_hooks.types.type_for_size (bitsiz[i], 1);
+ bitpos[i] = bit_pos;
+ ln_arg[i] = make_bit_field_ref (loc, inner, orig_inner,
+ type, bitsiz[i],
+ bit_pos, 1, reversep);
+ bit_pos += bitsiz[i];
+ }
+
+ toshift[1] = toshift[0];
+ if (reversep ? !BYTES_BIG_ENDIAN : BYTES_BIG_ENDIAN)
+ {
+ shifted[0] = bitsiz[1];
+ shifted[1] = 0;
+ toshift[0] = 0;
+ }
+ else
+ {
+ shifted[1] = bitsiz[0];
+ shifted[0] = 0;
+ toshift[1] = 0;
+ }
+}
+
+/* Make arrangements to split at bit BOUNDARY a single loaded word
+ (with REVERSEP bit order) LN_ARG[0], to be shifted right by
+ TOSHIFT[0] to bring the field of interest to the least-significant
+ bit. The expectation is that the same loaded word will be
+ propagated from part 0 to part 1, with just different shifting and
+ masking to extract both parts. MASK is not expected to do more
+ than masking out the bits that belong to the other part. See
+ build_split_load for more information on the other fields. */
+
+static inline void
+reuse_split_load (tree /* in[0] out[1] */ ln_arg[2],
+ HOST_WIDE_INT /* in[0] out[1] */ bitpos[2],
+ HOST_WIDE_INT /* in[0] out[1] */ bitsiz[2],
+ HOST_WIDE_INT /* in[0] out[0..1] */ toshift[2],
+ HOST_WIDE_INT /* out */ shifted[2],
+ tree /* out */ mask[2],
+ HOST_WIDE_INT boundary, bool reversep)
+{
+ ln_arg[1] = ln_arg[0];
+ bitpos[1] = bitpos[0];
+ bitsiz[1] = bitsiz[0];
+ shifted[1] = shifted[0] = 0;
+
+ tree basemask = build_int_cst_type (TREE_TYPE (ln_arg[0]), -1);
+
+ if (reversep ? !BYTES_BIG_ENDIAN : BYTES_BIG_ENDIAN)
+ {
+ toshift[1] = toshift[0];
+ toshift[0] = bitpos[0] + bitsiz[0] - boundary;
+ mask[0] = int_const_binop (LSHIFT_EXPR, basemask,
+ bitsize_int (toshift[0]));
+ mask[1] = int_const_binop (BIT_XOR_EXPR, basemask, mask[0]);
+ }
+ else
+ {
+ toshift[1] = boundary - bitpos[1];
+ mask[1] = int_const_binop (LSHIFT_EXPR, basemask,
+ bitsize_int (toshift[1]));
+ mask[0] = int_const_binop (BIT_XOR_EXPR, basemask, mask[1]);
+ }
+}
+
+/* Find ways of folding logical expressions of LHS and RHS:
+ Try to merge two comparisons to the same innermost item.
+ Look for range tests like "ch >= '0' && ch <= '9'".
+ Look for combinations of simple terms on machines with expensive branches
+ and evaluate the RHS unconditionally.
+
+ For example, if we have p->a == 2 && p->b == 4 and we can make an
+ object large enough to span both A and B, we can do this with a comparison
+ against the object ANDed with the a mask.
+
+ If we have p->a == q->a && p->b == q->b, we may be able to use bit masking
+ operations to do this with one comparison.
+
+ We check for both normal comparisons and the BIT_AND_EXPRs made this by
+ function and the one above.
+
+ CODE is the logical operation being done. It can be TRUTH_ANDIF_EXPR,
+ TRUTH_AND_EXPR, TRUTH_ORIF_EXPR, or TRUTH_OR_EXPR.
+
+ TRUTH_TYPE is the type of the logical operand and LHS and RHS are its
+ two operands.
+
+ SEPARATEP should be NULL if LHS and RHS are adjacent in
+ CODE-chained compares, and a non-NULL pointer to NULL_TREE
+ otherwise. If the "words" accessed by RHS are already accessed by
+ LHS, this won't matter, but if RHS accesses "words" that LHS
+ doesn't, then *SEPARATEP will be set to the compares that should
+ take RHS's place. By "words" we mean contiguous bits that do not
+ cross a an TYPE_ALIGN boundary of the accessed object's type.
+
+ We return the simplified tree or 0 if no optimization is possible. */
+
+tree
+fold_truth_andor_maybe_separate (location_t loc,
+ enum tree_code code, tree truth_type,
+ enum tree_code lcode, tree ll_arg, tree lr_arg,
+ enum tree_code rcode, tree rl_arg, tree rr_arg,
+ tree *separatep)
+{
+ /* If this is the "or" of two comparisons, we can do something if
+ the comparisons are NE_EXPR. If this is the "and", we can do something
+ if the comparisons are EQ_EXPR. I.e.,
+ (a->b == 2 && a->c == 4) can become (a->new == NEW).
+
+ WANTED_CODE is this operation code. For single bit fields, we can
+ convert EQ_EXPR to NE_EXPR so we need not reject the "wrong"
+ comparison for one-bit fields. */
+
+ enum tree_code orig_code = code;
+ enum tree_code wanted_code;
+ tree ll_inner, lr_inner, rl_inner, rr_inner;
+ HOST_WIDE_INT ll_bitsize, ll_bitpos, lr_bitsize, lr_bitpos;
+ HOST_WIDE_INT rl_bitsize, rl_bitpos, rr_bitsize, rr_bitpos;
+ HOST_WIDE_INT xll_bitpos, xlr_bitpos, xrl_bitpos, xrr_bitpos;
+ HOST_WIDE_INT lnbitsize, lnbitpos, rnbitsize, rnbitpos;
+ int ll_unsignedp, lr_unsignedp, rl_unsignedp, rr_unsignedp;
+ int ll_reversep, lr_reversep, rl_reversep, rr_reversep;
+ machine_mode ll_mode, lr_mode, rl_mode, rr_mode;
+ scalar_int_mode lnmode, lnmode2, rnmode;
+ tree ll_mask, lr_mask, rl_mask, rr_mask;
+ tree ll_and_mask, lr_and_mask, rl_and_mask, rr_and_mask;
+ tree l_const, r_const;
+ tree lntype, rntype, result;
+ HOST_WIDE_INT first_bit, end_bit;
+ int volatilep;
+ bool l_split_load;
+
+ gcc_checking_assert (!separatep || !*separatep);
+
+ /* Start by getting the comparison codes. Fail if anything is volatile.
+ If one operand is a BIT_AND_EXPR with the constant one, treat it as if
+ it were surrounded with a NE_EXPR. */
+
+ if (TREE_SIDE_EFFECTS (ll_arg) || TREE_SIDE_EFFECTS (lr_arg)
+ || TREE_SIDE_EFFECTS (rl_arg) || TREE_SIDE_EFFECTS (rr_arg))
+ return 0;
+
+ if (TREE_CODE_CLASS (lcode) != tcc_comparison
+ || TREE_CODE_CLASS (rcode) != tcc_comparison)
+ return 0;
+
+ code = ((code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR)
+ ? TRUTH_AND_EXPR : TRUTH_OR_EXPR);
+
+ bool lsignbit = false, rsignbit = false;
+ if ((lcode == LT_EXPR || lcode == GE_EXPR)
+ && integer_zerop (lr_arg)
+ && INTEGRAL_TYPE_P (TREE_TYPE (ll_arg))
+ && !TYPE_UNSIGNED (TREE_TYPE (ll_arg)))
+ {
+ lsignbit = true;
+ lcode = (lcode == LT_EXPR ? NE_EXPR : EQ_EXPR);
+ }
+ if ((rcode == LT_EXPR || rcode == GE_EXPR)
+ && integer_zerop (rr_arg)
+ && INTEGRAL_TYPE_P (TREE_TYPE (rl_arg))
+ && !TYPE_UNSIGNED (TREE_TYPE (rl_arg)))
+ {
+ rsignbit = true;
+ rcode = (rcode == LT_EXPR ? NE_EXPR : EQ_EXPR);
+ }
+
+ /* See if the comparisons can be merged. Then get all the parameters for
+ each side. */
+
+ if ((lcode != EQ_EXPR && lcode != NE_EXPR)
+ || (rcode != EQ_EXPR && rcode != NE_EXPR))
+ return 0;
+
+ ll_reversep = lr_reversep = rl_reversep = rr_reversep = 0;
+ volatilep = 0;
+ int l_xor = prepare_xor (ll_arg, &lr_arg);
+ ll_inner = decode_field_reference (loc, &ll_arg,
+ &ll_bitsize, &ll_bitpos, &ll_mode,
+ &ll_unsignedp, &ll_reversep, &volatilep,
+ &ll_mask, &ll_and_mask, l_xor);
+ lr_inner = decode_field_reference (loc, &lr_arg,
+ &lr_bitsize, &lr_bitpos, &lr_mode,
+ &lr_unsignedp, &lr_reversep, &volatilep,
+ &lr_mask, &lr_and_mask, 2 * l_xor);
+ int r_xor = prepare_xor (rl_arg, &rr_arg);
+ rl_inner = decode_field_reference (loc, &rl_arg,
+ &rl_bitsize, &rl_bitpos, &rl_mode,
+ &rl_unsignedp, &rl_reversep, &volatilep,
+ &rl_mask, &rl_and_mask, r_xor);
+ rr_inner = decode_field_reference (loc, &rr_arg,
+ &rr_bitsize, &rr_bitpos, &rr_mode,
+ &rr_unsignedp, &rr_reversep, &volatilep,
+ &rr_mask, &rr_and_mask, 2 * r_xor);
+
+ /* It must be true that the inner operation on the lhs of each
+ comparison must be the same if we are to be able to do anything.
+ Then see if we have constants. If not, the same must be true for
+ the rhs's. */
+ if (volatilep
+ || ll_reversep != rl_reversep
+ || ll_inner == 0 || rl_inner == 0
+ || ! operand_equal_p (ll_inner, rl_inner, 0))
+ return 0;
+
+ if (TREE_CODE (lr_arg) == INTEGER_CST
+ && TREE_CODE (rr_arg) == INTEGER_CST)
+ {
+ l_const = lr_arg, r_const = rr_arg;
+ lr_reversep = ll_reversep;
+ }
+ else if (lr_reversep != rr_reversep
+ || lr_inner == 0 || rr_inner == 0
+ || ! operand_equal_p (lr_inner, rr_inner, 0))
+ return 0;
+ else
+ l_const = r_const = 0;
+
+ if (lsignbit)
+ {
+ tree mask = build_int_cst_type (TREE_TYPE (ll_arg), -1);
+ tree sign = int_const_binop (LSHIFT_EXPR, mask,
+ bitsize_int (ll_bitsize - 1));
+ if (!ll_mask)
+ ll_mask = sign;
+ else
+ ll_mask = int_const_binop (BIT_AND_EXPR, ll_mask, sign);
+ if (!ll_and_mask)
+ ll_and_mask = sign;
+ else
+ ll_and_mask = int_const_binop (BIT_AND_EXPR, ll_and_mask, sign);
+ }
+
+ if (rsignbit)
+ {
+ tree mask = build_int_cst_type (TREE_TYPE (rl_arg), -1);
+ tree sign = int_const_binop (LSHIFT_EXPR, mask,
+ bitsize_int (rl_bitsize - 1));
+ if (!rl_mask)
+ rl_mask = sign;
+ else
+ rl_mask = int_const_binop (BIT_AND_EXPR, rl_mask, sign);
+ if (!rl_and_mask)
+ rl_and_mask = sign;
+ else
+ rl_and_mask = int_const_binop (BIT_AND_EXPR, rl_and_mask, sign);
+ }
+
+ /* If either comparison code is not correct for our logical operation,
+ fail. However, we can convert a one-bit comparison against zero into
+ the opposite comparison against that bit being set in the field. */
+
+ wanted_code = (code == TRUTH_AND_EXPR ? EQ_EXPR : NE_EXPR);
+ if (lcode != wanted_code)
+ {
+ if (l_const && integer_zerop (l_const) && integer_pow2p (ll_mask))
+ {
+ /* Make the left operand unsigned, since we are only interested
+ in the value of one bit. Otherwise we are doing the wrong
+ thing below. */
+ ll_unsignedp = 1;
+ l_const = ll_mask;
+ }
+ else
+ return 0;
+ }
+
+ /* This is analogous to the code for l_const above. */
+ if (rcode != wanted_code)
+ {
+ if (r_const && integer_zerop (r_const) && integer_pow2p (rl_mask))
+ {
+ rl_unsignedp = 1;
+ r_const = rl_mask;
+ }
+ else
+ return 0;
+ }
+
+ /* This will be bumped to 2 if any of the field pairs crosses an
+ alignment boundary, so the merged compare has to be done in two
+ parts. */
+ int parts = 1;
+ /* Set to true if the second combined compare should come first,
+ e.g., because the second original compare accesses a word that
+ the first one doesn't, and the combined compares access those in
+ cmp[0]. */
+ bool first1 = false;
+ /* Set to true if the first original compare is not the one being
+ split. */
+ bool maybe_separate = false;
+
+ /* The following 2-dimensional arrays use the first index to
+ identify left(0)- vs right(1)-hand compare operands, and the
+ second one to identify merged compare parts. */
+ /* The memory loads or constants to be compared. */
+ tree ld_arg[2][2];
+ /* The first bit of the corresponding inner object that the
+ corresponding LD_ARG covers. */
+ HOST_WIDE_INT bitpos[2][2];
+ /* The bit count starting at BITPOS that the corresponding LD_ARG
+ covers. */
+ HOST_WIDE_INT bitsiz[2][2];
+ /* The number of bits by which LD_ARG has already been shifted
+ right, WRT mask. */
+ HOST_WIDE_INT shifted[2][2];
+ /* The number of bits by which both LD_ARG and MASK need shifting to
+ bring its least-significant bit to bit zero. */
+ HOST_WIDE_INT toshift[2][2];
+ /* An additional mask to be applied to LD_ARG, to remove any bits
+ that may have been loaded for use in another compare, but that
+ don't belong in the corresponding compare. */
+ tree xmask[2][2] = {};
+
+ /* The combined compare or compares. */
+ tree cmp[2];
+
+ /* Consider we're comparing two non-contiguous fields of packed
+ structs, both aligned at 32-bit boundaries:
+
+ ll_arg: an 8-bit field at offset 0
+ lr_arg: a 16-bit field at offset 2
+
+ rl_arg: an 8-bit field at offset 1
+ rr_arg: a 16-bit field at offset 3
+
+ We'll have r_split_load, because rr_arg straddles across an
+ alignment boundary.
+
+ We'll want to have:
+
+ bitpos = { { 0, 0 }, { 0, 32 } }
+ bitsiz = { { 32, 32 }, { 32, 8 } }
+
+ And, for little-endian:
+
+ shifted = { { 0, 0 }, { 0, 32 } }
+ toshift = { { 0, 24 }, { 0, 0 } }
+
+ Or, for big-endian:
+
+ shifted = { { 0, 0 }, { 8, 0 } }
+ toshift = { { 8, 0 }, { 0, 0 } }
+ */
+
+ /* See if we can find a mode that contains both fields being compared on
+ the left. If we can't, fail. Otherwise, update all constants and masks
+ to be relative to a field of that size. */
+ first_bit = MIN (ll_bitpos, rl_bitpos);
+ end_bit = MAX (ll_bitpos + ll_bitsize, rl_bitpos + rl_bitsize);
+ if (!get_best_mode (end_bit - first_bit, first_bit, 0, 0,
+ TYPE_ALIGN (TREE_TYPE (ll_inner)), BITS_PER_WORD,
+ volatilep, &lnmode))
+ {
+ /* Consider the possibility of recombining loads if any of the
+ fields straddles across an alignment boundary, so that either
+ part can be loaded along with the other field. */
+ HOST_WIDE_INT align = TYPE_ALIGN (TREE_TYPE (ll_inner));
+ HOST_WIDE_INT boundary = compute_split_boundary_from_align
+ (align, ll_bitpos, ll_bitsize, rl_bitpos, rl_bitsize);
+
+ if (boundary < 0
+ || !get_best_mode (boundary - first_bit, first_bit, 0, 0,
+ align, BITS_PER_WORD, volatilep, &lnmode)
+ || !get_best_mode (end_bit - boundary, boundary, 0, 0,
+ align, BITS_PER_WORD, volatilep, &lnmode2))
+ return 0;
+
+ l_split_load = true;
+ parts = 2;
+ if (ll_bitpos >= boundary)
+ maybe_separate = first1 = true;
+ else if (ll_bitpos + ll_bitsize <= boundary)
+ maybe_separate = true;
+ }
+ else
+ l_split_load = false;
+
+ lnbitsize = GET_MODE_BITSIZE (lnmode);
+ lnbitpos = first_bit & ~ (lnbitsize - 1);
+ if (l_split_load)
+ lnbitsize += GET_MODE_BITSIZE (lnmode2);
+ lntype = lang_hooks.types.type_for_size (lnbitsize, 1);
+ if (!lntype)
+ {
+ gcc_checking_assert (l_split_load);
+ lntype = build_nonstandard_integer_type (lnbitsize, 1);
+ }
+ xll_bitpos = ll_bitpos - lnbitpos, xrl_bitpos = rl_bitpos - lnbitpos;
+
+ if (ll_reversep ? !BYTES_BIG_ENDIAN : BYTES_BIG_ENDIAN)
+ {
+ xll_bitpos = lnbitsize - xll_bitpos - ll_bitsize;
+ xrl_bitpos = lnbitsize - xrl_bitpos - rl_bitsize;
+ }
+
+ ll_mask = int_const_binop (LSHIFT_EXPR,
+ fold_convert_loc (loc, lntype, ll_mask),
+ size_int (xll_bitpos));
+ if (!ll_mask)
+ return 0;
+ rl_mask = int_const_binop (LSHIFT_EXPR,
+ fold_convert_loc (loc, lntype, rl_mask),
+ size_int (xrl_bitpos));
+ if (!rl_mask)
+ return 0;
+
+ if (l_const)
+ {
+ l_const = fold_convert_loc (loc, lntype, l_const);
+ l_const = unextend (l_const, ll_bitsize, ll_unsignedp, ll_and_mask);
+ l_const = int_const_binop (LSHIFT_EXPR, l_const, size_int (xll_bitpos));
+ if (! integer_zerop (int_const_binop (BIT_AND_EXPR, l_const,
+ fold_build1_loc (loc, BIT_NOT_EXPR,
+ lntype, ll_mask))))
+ {
+ warning (0, "comparison is always %d", wanted_code == NE_EXPR);
+
+ return constant_boolean_node (wanted_code == NE_EXPR, truth_type);
+ }
+ }
+ if (r_const)
+ {
+ r_const = fold_convert_loc (loc, lntype, r_const);
+ r_const = unextend (r_const, rl_bitsize, rl_unsignedp, rl_and_mask);
+ r_const = int_const_binop (LSHIFT_EXPR, r_const, size_int (xrl_bitpos));
+ if (! integer_zerop (int_const_binop (BIT_AND_EXPR, r_const,
+ fold_build1_loc (loc, BIT_NOT_EXPR,
+ lntype, rl_mask))))
+ {
+ warning (0, "comparison is always %d", wanted_code == NE_EXPR);
+
+ return constant_boolean_node (wanted_code == NE_EXPR, truth_type);
+ }
+ }
+
+ /* If the right sides are not constant, do the same for it. Also,
+ disallow this optimization if a size, signedness or storage order
+ mismatch occurs between the left and right sides. */
+ if (l_const == 0)
+ {
+ if (ll_bitsize != lr_bitsize || rl_bitsize != rr_bitsize
+ || ll_unsignedp != lr_unsignedp || rl_unsignedp != rr_unsignedp
+ || ll_reversep != lr_reversep
+ /* Make sure the two fields on the right
+ correspond to the left without being swapped. */
+ || ll_bitpos - rl_bitpos != lr_bitpos - rr_bitpos
+ || lnbitpos < 0)
+ return 0;
+
+ bool r_split_load;
+ scalar_int_mode rnmode2;
+
+ first_bit = MIN (lr_bitpos, rr_bitpos);
+ end_bit = MAX (lr_bitpos + lr_bitsize, rr_bitpos + rr_bitsize);
+ if (!get_best_mode (end_bit - first_bit, first_bit, 0, 0,
+ TYPE_ALIGN (TREE_TYPE (lr_inner)), BITS_PER_WORD,
+ volatilep, &rnmode))
+ {
+ /* Consider the possibility of recombining loads if any of the
+ fields straddles across an alignment boundary, so that either
+ part can be loaded along with the other field. */
+ HOST_WIDE_INT align = TYPE_ALIGN (TREE_TYPE (lr_inner));
+ HOST_WIDE_INT boundary = compute_split_boundary_from_align
+ (align, lr_bitpos, lr_bitsize, rr_bitpos, rr_bitsize);
+
+ if (boundary < 0
+ /* If we're to split both, make sure the split point is
+ the same. */
+ || (l_split_load
+ && (boundary - lr_bitpos
+ != (lnbitpos + GET_MODE_BITSIZE (lnmode)) - ll_bitpos))
+ || !get_best_mode (boundary - first_bit, first_bit, 0, 0,
+ align, BITS_PER_WORD, volatilep, &rnmode)
+ || !get_best_mode (end_bit - boundary, boundary, 0, 0,
+ align, BITS_PER_WORD, volatilep, &rnmode2))
+ return 0;
+
+ r_split_load = true;
+ parts = 2;
+ if (lr_bitpos >= boundary)
+ maybe_separate = first1 = true;
+ else if (lr_bitpos + lr_bitsize <= boundary)
+ maybe_separate = true;
+ }
+ else
+ r_split_load = false;
+
+ rnbitsize = GET_MODE_BITSIZE (rnmode);
+ rnbitpos = first_bit & ~ (rnbitsize - 1);
+ if (r_split_load)
+ rnbitsize += GET_MODE_BITSIZE (rnmode2);
+ rntype = lang_hooks.types.type_for_size (rnbitsize, 1);
+ if (!rntype)
+ {
+ gcc_checking_assert (r_split_load);
+ rntype = build_nonstandard_integer_type (rnbitsize, 1);
+ }
+ xlr_bitpos = lr_bitpos - rnbitpos, xrr_bitpos = rr_bitpos - rnbitpos;
+
+ if (lr_reversep ? !BYTES_BIG_ENDIAN : BYTES_BIG_ENDIAN)
+ {
+ xlr_bitpos = rnbitsize - xlr_bitpos - lr_bitsize;
+ xrr_bitpos = rnbitsize - xrr_bitpos - rr_bitsize;
+ }
+
+ lr_mask = int_const_binop (LSHIFT_EXPR,
+ fold_convert_loc (loc, rntype, lr_mask),
+ size_int (xlr_bitpos));
+ rr_mask = int_const_binop (LSHIFT_EXPR,
+ fold_convert_loc (loc, rntype, rr_mask),
+ size_int (xrr_bitpos));
+ lr_mask = int_const_binop (BIT_IOR_EXPR, lr_mask, rr_mask);
+
+ toshift[1][0] = MIN (xlr_bitpos, xrr_bitpos);
+ shifted[1][0] = 0;
+
+ if (!r_split_load)
+ {
+ bitpos[1][0] = rnbitpos;
+ bitsiz[1][0] = rnbitsize;
+ ld_arg[1][0] = make_bit_field_ref (loc, lr_inner, lr_arg,
+ rntype, rnbitsize, rnbitpos,
+ lr_unsignedp || rr_unsignedp,
+ lr_reversep);
+ }
+
+ if (parts > 1)
+ {
+ if (r_split_load)
+ build_split_load (ld_arg[1], bitpos[1], bitsiz[1], toshift[1],
+ shifted[1], loc, lr_inner, lr_arg,
+ rnmode, rnmode2, rnbitpos, lr_reversep);
+ else
+ reuse_split_load (ld_arg[1], bitpos[1], bitsiz[1], toshift[1],
+ shifted[1], xmask[1],
+ lnbitpos + GET_MODE_BITSIZE (lnmode)
+ - ll_bitpos + lr_bitpos, lr_reversep);
+ }
+ }
+ else
+ {
+ /* Handle the case of comparisons with constants. If there is
+ something in common between the masks, those bits of the
+ constants must be the same. If not, the condition is always
+ false. Test for this to avoid generating incorrect code
+ below. */
+ result = int_const_binop (BIT_AND_EXPR, ll_mask, rl_mask);
+ if (! integer_zerop (result)
+ && simple_cst_equal (int_const_binop (BIT_AND_EXPR,
+ result, l_const),
+ int_const_binop (BIT_AND_EXPR,
+ result, r_const)) != 1)
+ {
+ if (wanted_code == NE_EXPR)
+ {
+ warning (0,
+ "%<or%> of unmatched not-equal tests"
+ " is always 1");
+ return constant_boolean_node (true, truth_type);
+ }
+ else
+ {
+ warning (0,
+ "%<and%> of mutually exclusive equal-tests"
+ " is always 0");
+ return constant_boolean_node (false, truth_type);
+ }
+ }
+
+ if (lnbitpos < 0)
+ return 0;
+
+ /* The constants are combined so as to line up with the loaded
+ field, so use the same parameters. */
+ ld_arg[1][0] = int_const_binop (BIT_IOR_EXPR, l_const, r_const);
+ toshift[1][0] = MIN (xll_bitpos, xrl_bitpos);
+ shifted[1][0] = 0;
+ bitpos[1][0] = lnbitpos;
+ bitsiz[1][0] = lnbitsize;
+
+ if (parts > 1)
+ reuse_split_load (ld_arg[1], bitpos[1], bitsiz[1], toshift[1],
+ shifted[1], xmask[1],
+ lnbitpos + GET_MODE_BITSIZE (lnmode),
+ lr_reversep);
+
+ lr_mask = build_int_cst_type (TREE_TYPE (ld_arg[1][0]), -1);
+
+ /* If the compiler thinks this is used uninitialized below, it's
+ because it can't realize that parts can only be 2 when
+ comparing wiht constants if l_split_load is also true. This
+ just silences the warning. */
+ rnbitpos = 0;
+ }
+
+ ll_mask = int_const_binop (BIT_IOR_EXPR, ll_mask, rl_mask);
+ toshift[0][0] = MIN (xll_bitpos, xrl_bitpos);
+ shifted[0][0] = 0;
+
+ if (!l_split_load)
+ {
+ bitpos[0][0] = lnbitpos;
+ bitsiz[0][0] = lnbitsize;
+ ld_arg[0][0] = make_bit_field_ref (loc, ll_inner, ll_arg,
+ lntype, lnbitsize, lnbitpos,
+ ll_unsignedp || rl_unsignedp,
+ ll_reversep);
+ }
+
+ if (parts > 1)
+ {
+ if (l_split_load)
+ build_split_load (ld_arg[0], bitpos[0], bitsiz[0], toshift[0],
+ shifted[0], loc, ll_inner, ll_arg,
+ lnmode, lnmode2, lnbitpos, ll_reversep);
+ else
+ reuse_split_load (ld_arg[0], bitpos[0], bitsiz[0], toshift[0],
+ shifted[0], xmask[0],
+ rnbitpos + GET_MODE_BITSIZE (rnmode)
+ - lr_bitpos + ll_bitpos, ll_reversep);
+ }
+
+ for (int i = 0; i < parts; i++)
+ {
+ tree op[2] = { ld_arg[0][i], ld_arg[1][i] };
+ tree mask[2] = { ll_mask, lr_mask };
+
+ for (int j = 0; j < 2; j++)
+ {
+ /* Mask out the bits belonging to the other part. */
+ if (xmask[j][i])
+ mask[j] = int_const_binop (BIT_AND_EXPR, mask[j], xmask[j][i]);
+
+ if (shifted[j][i])
+ {
+ tree shiftsz = bitsize_int (shifted[j][i]);
+ mask[j] = int_const_binop (RSHIFT_EXPR, mask[j], shiftsz);
+ }
+ mask[j] = fold_convert_loc (loc, TREE_TYPE (op[j]), mask[j]);
+ }
+
+ HOST_WIDE_INT shift = (toshift[0][i] - toshift[1][i]);
+
+ if (shift)
+ {
+ int j;
+ if (shift > 0)
+ j = 0;
+ else
+ {
+ j = 1;
+ shift = -shift;
+ }
+
+ tree shiftsz = bitsize_int (shift);
+ op[j] = fold_build2_loc (loc, RSHIFT_EXPR, TREE_TYPE (op[j]),
+ op[j], shiftsz);
+ mask[j] = int_const_binop (RSHIFT_EXPR, mask[j], shiftsz);
+ }
+
+ /* Convert to the smaller type before masking out unwanted
+ bits. */
+ tree type = TREE_TYPE (op[0]);
+ if (type != TREE_TYPE (op[1]))
+ {
+ int j = (TYPE_PRECISION (type)
+ < TYPE_PRECISION (TREE_TYPE (op[1])));
+ if (!j)
+ type = TREE_TYPE (op[1]);
+ op[j] = fold_convert_loc (loc, type, op[j]);
+ mask[j] = fold_convert_loc (loc, type, mask[j]);
+ }
+
+ for (int j = 0; j < 2; j++)
+ if (! integer_all_onesp (mask[j]))
+ op[j] = build2_loc (loc, BIT_AND_EXPR, type,
+ op[j], mask[j]);
+
+ cmp[i] = build2_loc (loc, wanted_code, truth_type, op[0], op[1]);
+ }
+
+ if (first1)
+ std::swap (cmp[0], cmp[1]);
+
+ if (parts == 1)
+ result = cmp[0];
+ else if (!separatep || !maybe_separate)
+ result = build2_loc (loc, orig_code, truth_type, cmp[0], cmp[1]);
+ else
+ {
+ result = cmp[0];
+ *separatep = cmp[1];
+ }
+
+ return result;
+}
+
/* Try to simplify the AND of two comparisons, specified by
(OP1A CODE1 OP1B) and (OP2B CODE2 OP2B), respectively.
If this can be simplified to a single expression (without requiring
@@ -7411,6 +8553,13 @@ maybe_fold_and_comparisons (tree type,
op2b, outer_cond_bb))
return t;
+ if (tree t = fold_truth_andor_maybe_separate (UNKNOWN_LOCATION,
+ TRUTH_ANDIF_EXPR, type,
+ code2, op2a, op2b,
+ code1, op1a, op1b,
+ NULL))
+ return t;
+
return NULL_TREE;
}
diff --git a/gcc/tree-ssa-ifcombine.cc b/gcc/tree-ssa-ifcombine.cc
index 6a3bc99190d9..79a4bdd363b9 100644
--- a/gcc/tree-ssa-ifcombine.cc
+++ b/gcc/tree-ssa-ifcombine.cc
@@ -601,8 +601,8 @@ ifcombine_ifandif (basic_block inner_cond_bb, bool
inner_inv,
gimple_cond_rhs (outer_cond),
gimple_bb (outer_cond))))
{
+ {
tree t1, t2;
- gimple_stmt_iterator gsi;
bool logical_op_non_short_circuit = LOGICAL_OP_NON_SHORT_CIRCUIT;
if (param_logical_op_non_short_circuit != -1)
logical_op_non_short_circuit
@@ -624,6 +624,8 @@ ifcombine_ifandif (basic_block inner_cond_bb, bool
inner_inv,
gimple_cond_rhs (outer_cond));
t = fold_build2_loc (gimple_location (inner_cond),
TRUTH_AND_EXPR, boolean_type_node, t1, t2);
+ }
+ gimplify_after_fold:
if (result_inv)
{
t = fold_build1 (TRUTH_NOT_EXPR, TREE_TYPE (t), t);
@@ -633,6 +635,9 @@ ifcombine_ifandif (basic_block inner_cond_bb, bool
inner_inv,
t = force_gimple_operand_gsi_1 (&gsi, t, is_gimple_condexpr_for_cond,
NULL, true, GSI_SAME_STMT);
}
+ /* ??? Fold should avoid this. */
+ else if (!is_gimple_condexpr_for_cond (t))
+ goto gimplify_after_fold;
if (result_inv)
t = fold_build1 (TRUTH_NOT_EXPR, TREE_TYPE (t), t);
t = canonicalize_cond_expr_cond (t);
