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| author | Jakub Jelinek <jakub@redhat.com> | 2024-02-07 10:59:06 +0100 |
|---|---|---|
| committer | Jakub Jelinek <jakub@redhat.com> | 2024-02-07 10:59:06 +0100 |
| commit | 29998cc8a21b3a52f706275923166cd1f95d0555 (patch) | |
| tree | 2a8c151e4049b2416eba2d90aa197ec85b0e0d87 | |
| parent | 6e308d5f71a91225946c199e69708adc92404975 (diff) | |
| download | gcc-29998cc8a21b3a52f706275923166cd1f95d0555.zip gcc-29998cc8a21b3a52f706275923166cd1f95d0555.tar.gz gcc-29998cc8a21b3a52f706275923166cd1f95d0555.tar.bz2 | |
range-op: Fix up ABSU_EXPR handling [PR113756]
ABSU_EXPR unary expr is special because it has a signed integer
argument and unsigned integer result (of the same precision).
The following testcase is miscompiled since ABSU_EXPR handling has
been added to range-op because it uses widest_int::from with the
result sign (i.e. UNSIGNED) rather than the operand sign (i.e. SIGNED),
so e.g. for the 32-bit int argument mask ends up 0xffffffc1 or something
similar and even when it has most significant bit in the precision set,
in widest_int (tree-ssa-ccp.cc really should stop using widest_int, but
that is I think stage1 task) it doesn't appear to be negative and so
bit_value_unop ABSU_EXPR doesn't set the resulting mask/value from
oring of the argument and its negation.
Fixed thusly, not doing that for GIMPLE_BINARY_RHS because I don't know
about a binary op that would need something similar.
2024-02-06 Jakub Jelinek <jakub@redhat.com>
PR tree-optimization/113756
* range-op.cc (update_known_bitmask): For GIMPLE_UNARY_RHS,
use TYPE_SIGN (lh.type ()) instead of sign for widest_int::from
of lh_bits value and mask.
* gcc.dg/pr113756.c: New test.
| -rw-r--r-- | gcc/range-op.cc | 6 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.dg/pr113756.c | 36 |
2 files changed, 40 insertions, 2 deletions
diff --git a/gcc/range-op.cc b/gcc/range-op.cc index 9a1a3c8..4ccb86e 100644 --- a/gcc/range-op.cc +++ b/gcc/range-op.cc @@ -435,8 +435,10 @@ update_known_bitmask (irange &r, tree_code code, bit_value_unop (code, sign, prec, &widest_value, &widest_mask, TYPE_SIGN (lh.type ()), TYPE_PRECISION (lh.type ()), - widest_int::from (lh_bits.value (), sign), - widest_int::from (lh_bits.mask (), sign)); + widest_int::from (lh_bits.value (), + TYPE_SIGN (lh.type ())), + widest_int::from (lh_bits.mask (), + TYPE_SIGN (lh.type ()))); break; case GIMPLE_BINARY_RHS: bit_value_binop (code, sign, prec, &widest_value, &widest_mask, diff --git a/gcc/testsuite/gcc.dg/pr113756.c b/gcc/testsuite/gcc.dg/pr113756.c new file mode 100644 index 0000000..1444220 --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr113756.c @@ -0,0 +1,36 @@ +/* PR tree-optimization/113756 */ +/* { dg-do run { target int32plus } } */ +/* { dg-options "-O2" } */ + +int d, e, i, k, l = -8; +signed char h, j; + +int +bar (int n, int o, int p3) +{ + int a = o - p3, b = n - p3, c = a + b, f = -b, g = c < 0 ? -c : c; + return a <= f && a <= g ? o : p3; +} + +void +foo (int *n, unsigned short o) +{ + unsigned p = 8896; + for (; e >= 0; e--) + p = 5377; + for (; h <= 0; h++) + for (; j <= 0; j++) + { + *n = 1611581749; + i = bar (34, p - 5294, *n - 1611581687); + k = i + p + 65535 + o + *n - 1611718251; + if (k != 0) + __builtin_abort (); + } +} + +int +main () +{ + foo (&l, l); +} |