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| author | Jakub Jelinek <jakub@gcc.gnu.org> | 2013-01-28 15:43:03 +0100 |
|---|---|---|
| committer | Jakub Jelinek <jakub@gcc.gnu.org> | 2013-01-28 15:43:03 +0100 |
| commit | 0bfbca5868fae1912db33ae4ab341d6e08bd68b4 (patch) | |
| tree | 2a2bfc3d290925073d4af913ae01b69cfbf1aa53 /gcc/testsuite/gcc.dg/pr56125.c | |
| parent | dd8b9ddea2288c96124367bf66ce060eb1049872 (diff) | |
| download | gcc-0bfbca5868fae1912db33ae4ab341d6e08bd68b4.zip gcc-0bfbca5868fae1912db33ae4ab341d6e08bd68b4.tar.gz gcc-0bfbca5868fae1912db33ae4ab341d6e08bd68b4.tar.bz2 | |
re PR tree-optimization/56125 (-O2 -ffast-math generates bad code when dividing a double by the square of another double.)
PR tree-optimization/56125
* tree-ssa-math-opts.c (gimple_expand_builtin_pow): Don't optimize
pow(x,c) into sqrt(x) * powi(x, n/2) or
1.0 / (sqrt(x) * powi(x, abs(n/2))) if c is an integer or when
optimizing for size.
Don't optimize pow(x,c) into powi(x, n/3) * powi(cbrt(x), n%3) or
1.0 / (powi(x, abs(n)/3) * powi(cbrt(x), abs(n)%3)) if 2c is an
integer.
* gcc.dg/pr56125.c: New test.
From-SVN: r195507
Diffstat (limited to 'gcc/testsuite/gcc.dg/pr56125.c')
| -rw-r--r-- | gcc/testsuite/gcc.dg/pr56125.c | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/gcc/testsuite/gcc.dg/pr56125.c b/gcc/testsuite/gcc.dg/pr56125.c new file mode 100644 index 0000000..d1840a9 --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr56125.c @@ -0,0 +1,21 @@ +/* PR tree-optimization/56125 */ +/* { dg-do run } */ +/* { dg-options "-O2 -ffast-math" } */ + +extern void abort (void); +extern double fabs (double); + +__attribute__((cold)) double +foo (double x, double n) +{ + double u = x / (n * n); + return u; +} + +int +main () +{ + if (fabs (foo (29, 2) - 7.25) > 0.001) + abort (); + return 0; +} |