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| author | Bill Schmidt <wschmidt@linux.vnet.ibm.com> | 2014-04-25 14:28:58 +0000 |
|---|---|---|
| committer | William Schmidt <wschmidt@gcc.gnu.org> | 2014-04-25 14:28:58 +0000 |
| commit | 61ba73292722363dd1b1317aed03713df7f220be (patch) | |
| tree | 1b203dd28338d28e3b1e6d6254f8c66033429a5e /gcc | |
| parent | 2b33282907e37ff709826b7f60832b036ceb6cbd (diff) | |
| download | gcc-61ba73292722363dd1b1317aed03713df7f220be.zip gcc-61ba73292722363dd1b1317aed03713df7f220be.tar.gz gcc-61ba73292722363dd1b1317aed03713df7f220be.tar.bz2 | |
re PR tree-optimization/60930 (Wrong folding of - ((unsigned long long) a * (unsigned long long) (unsigned int)-1))
[gcc]
2014-04-25 Bill Schmidt <wschmidt@linux.vnet.ibm.com>
PR tree-optimization/60930
* gimple-ssa-strength-reduction.c (create_mul_imm_cand): Reject
creating a multiply candidate by folding two constant
multiplicands when the result overflows.
[gcc/testsuite]
2014-04-25 Bill Schmidt <wschmidt@linux.vnet.ibm.com>
PR tree-optimization/60930
* gcc.dg/torture/pr60930.c: New test.
From-SVN: r209805
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 7 | ||||
| -rw-r--r-- | gcc/gimple-ssa-strength-reduction.c | 17 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.dg/torture/pr60930.c | 22 |
4 files changed, 44 insertions, 7 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index b5f0816..228404c 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +2014-04-25 Bill Schmidt <wschmidt@linux.vnet.ibm.com> + + PR tree-optimization/60930 + * gimple-ssa-strength-reduction.c (create_mul_imm_cand): Reject + creating a multiply candidate by folding two constant + multiplicands when the result overflows. + 2014-04-25 Jakub Jelinek <jakub@redhat.com> PR tree-optimization/60960 diff --git a/gcc/gimple-ssa-strength-reduction.c b/gcc/gimple-ssa-strength-reduction.c index ff55d0e..321cb15 100644 --- a/gcc/gimple-ssa-strength-reduction.c +++ b/gcc/gimple-ssa-strength-reduction.c @@ -1114,15 +1114,18 @@ create_mul_imm_cand (gimple gs, tree base_in, tree stride_in, bool speed) X = Y * c ============================ X = (B + i') * (S * c) */ - base = base_cand->base_expr; - index = base_cand->index; temp = tree_to_double_int (base_cand->stride) * tree_to_double_int (stride_in); - stride = double_int_to_tree (TREE_TYPE (stride_in), temp); - ctype = base_cand->cand_type; - if (has_single_use (base_in)) - savings = (base_cand->dead_savings - + stmt_cost (base_cand->cand_stmt, speed)); + if (double_int_fits_to_tree_p (TREE_TYPE (stride_in), temp)) + { + base = base_cand->base_expr; + index = base_cand->index; + stride = double_int_to_tree (TREE_TYPE (stride_in), temp); + ctype = base_cand->cand_type; + if (has_single_use (base_in)) + savings = (base_cand->dead_savings + + stmt_cost (base_cand->cand_stmt, speed)); + } } else if (base_cand->kind == CAND_ADD && integer_onep (base_cand->stride)) { diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 728a267..0d65bef 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2014-04-25 Bill Schmidt <wschmidt@linux.vnet.ibm.com> + + PR tree-optimization/60930 + * gcc.dg/torture/pr60930.c: New test. + 2014-04-25 Jakub Jelinek <jakub@redhat.com> PR tree-optimization/60960 diff --git a/gcc/testsuite/gcc.dg/torture/pr60930.c b/gcc/testsuite/gcc.dg/torture/pr60930.c new file mode 100644 index 0000000..5e35f19 --- /dev/null +++ b/gcc/testsuite/gcc.dg/torture/pr60930.c @@ -0,0 +1,22 @@ +/* { dg-do run } */ + +int x = 1; + +__attribute__((noinline, noclone)) void +foo (unsigned long long t) +{ + asm volatile ("" : : "r" (&t)); + if (t == 1) + __builtin_abort (); +} + +int +main () +{ +#if __SIZEOF_LONG_LONG__ >= 8 + unsigned long long t = 0xffffffffffffffffULL * (0xffffffffUL * x); + if (t != 0xffffffff00000001ULL) + foo (t);; +#endif + return 0; +} |