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| author | Richard Biener <rguenther@suse.de> | 2021-05-19 13:35:07 +0200 |
|---|---|---|
| committer | Richard Biener <rguenther@suse.de> | 2021-05-19 15:41:19 +0200 |
| commit | 8d51039cb7c807ed84ff7df5416a1e3ba07a5e63 (patch) | |
| tree | 4db5ca7df36f333472033131dd2b72e26b40ded2 /gcc | |
| parent | 32bd0353db37af2cb023e575ed4ce8c944fd9dba (diff) | |
| download | gcc-8d51039cb7c807ed84ff7df5416a1e3ba07a5e63.zip gcc-8d51039cb7c807ed84ff7df5416a1e3ba07a5e63.tar.gz gcc-8d51039cb7c807ed84ff7df5416a1e3ba07a5e63.tar.bz2 | |
middle-end/100672 - fix bogus right shift folding
This fixes the bogus use of TYPE_PRECISION on vector types
from optimizing -((int)x >> 31) into (unsigned)x >> 31.
2021-05-19 Richard Biener <rguenther@suse.de>
PR middle-end/100672
* fold-const.c (fold_negate_expr_1): Use element_precision.
(negate_expr_p): Likewise.
* gcc.dg/torture/pr100672.c: New testcase.
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/fold-const.c | 4 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.dg/torture/pr100672.c | 19 |
2 files changed, 21 insertions, 2 deletions
diff --git a/gcc/fold-const.c b/gcc/fold-const.c index 5a41524..3be9c15 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -512,7 +512,7 @@ negate_expr_p (tree t) if (TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST) { tree op1 = TREE_OPERAND (t, 1); - if (wi::to_wide (op1) == TYPE_PRECISION (type) - 1) + if (wi::to_wide (op1) == element_precision (type) - 1) return true; } break; @@ -705,7 +705,7 @@ fold_negate_expr_1 (location_t loc, tree t) if (TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST) { tree op1 = TREE_OPERAND (t, 1); - if (wi::to_wide (op1) == TYPE_PRECISION (type) - 1) + if (wi::to_wide (op1) == element_precision (type) - 1) { tree ntype = TYPE_UNSIGNED (type) ? signed_type_for (type) diff --git a/gcc/testsuite/gcc.dg/torture/pr100672.c b/gcc/testsuite/gcc.dg/torture/pr100672.c new file mode 100644 index 0000000..cc62e71 --- /dev/null +++ b/gcc/testsuite/gcc.dg/torture/pr100672.c @@ -0,0 +1,19 @@ +/* { dg-do run } */ +/* { dg-additional-options "-w -Wno-psabi" } */ + +typedef long long __attribute__((__vector_size__ (4 * sizeof (long long)))) V; + +V +foo (V v) +{ + return -(v >> 1); +} + +int +main (void) +{ + V v = foo ((V) { -2, -4, -6, -8 }); + if (v[0] != 1 || v[1] != 2 || v[2] != 3 || v[3] != 4) + __builtin_abort (); + return 0; +} |