diff options
| author | liuhongt <hongtao.liu@intel.com> | 2023-06-25 11:35:09 +0800 |
|---|---|---|
| committer | liuhongt <hongtao.liu@intel.com> | 2023-06-26 15:30:06 +0800 |
| commit | 77a50c772771f681085922b493922516c3c03e9a (patch) | |
| tree | 3d98bbae5e0cc8315da95c616723e35efd186f66 | |
| parent | 2916278d14e9ac28c361c396a67256acbebda6e8 (diff) | |
Don't use intermiediate type for FIX_TRUNC_EXPR when ftrapping-math.
> > Hmm, good question. GENERIC has a direct truncation to unsigned char
> > for example, the C standard generally says if the integral part cannot
> > be represented then the behavior is undefined. So I think we should be
> > safe here (0x1.0p32 doesn't fit an int).
>
> We should be following Annex F (unspecified value plus "invalid" exception
> for out-of-range floating-to-integer conversions rather than undefined
> behavior). But we don't achieve that very well at present (see bug 93806
> comments 27-29 for examples of how such conversions produce wobbly
> values).
That would mean guarding this with !flag_trapping_math would be the appropriate
thing to do.
gcc/ChangeLog:
PR tree-optimization/110371
PR tree-optimization/110018
* tree-vect-stmts.cc (vectorizable_conversion): Don't use
intermiediate type for FIX_TRUNC_EXPR when ftrapping-math.
gcc/testsuite/ChangeLog:
* gcc.target/i386/pr110018-1.c: Add -fno-trapping-math to dg-options.
* gcc.target/i386/pr110018-2.c: Ditto.
| -rw-r--r-- | gcc/testsuite/gcc.target/i386/pr110018-1.c | 2 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.target/i386/pr110018-2.c | 2 | ||||
| -rw-r--r-- | gcc/tree-vect-stmts.cc | 3 |
3 files changed, 4 insertions, 3 deletions
diff --git a/gcc/testsuite/gcc.target/i386/pr110018-1.c b/gcc/testsuite/gcc.target/i386/pr110018-1.c index b6a3be7b7a2..24eeca60f6f 100644 --- a/gcc/testsuite/gcc.target/i386/pr110018-1.c +++ b/gcc/testsuite/gcc.target/i386/pr110018-1.c @@ -1,5 +1,5 @@ /* { dg-do compile } */ -/* { dg-options "-mavx512fp16 -mavx512vl -O2 -mavx512dq" } */ +/* { dg-options "-mavx512fp16 -mavx512vl -O2 -mavx512dq -fno-trapping-math" } */ /* { dg-final { scan-assembler-times {(?n)vcvttp[dsh]2[dqw]} 5 } } */ /* { dg-final { scan-assembler-times {(?n)vcvt[dqw]*2p[dsh]} 5 } } */ diff --git a/gcc/testsuite/gcc.target/i386/pr110018-2.c b/gcc/testsuite/gcc.target/i386/pr110018-2.c index a663e074698..9a2d9e17894 100644 --- a/gcc/testsuite/gcc.target/i386/pr110018-2.c +++ b/gcc/testsuite/gcc.target/i386/pr110018-2.c @@ -1,5 +1,5 @@ /* { dg-do compile } */ -/* { dg-options "-mavx512fp16 -mavx512vl -O2 -mavx512dq" } */ +/* { dg-options "-mavx512fp16 -mavx512vl -O2 -mavx512dq -fno-trapping-math" } */ /* { dg-final { scan-assembler-times {(?n)vcvttp[dsh]2[dqw]} 5 } } */ /* { dg-final { scan-assembler-times {(?n)vcvt[dqw]*2p[dsh]} 5 } } */ diff --git a/gcc/tree-vect-stmts.cc b/gcc/tree-vect-stmts.cc index 85d1f3ae52c..7d24bbee152 100644 --- a/gcc/tree-vect-stmts.cc +++ b/gcc/tree-vect-stmts.cc @@ -5263,7 +5263,8 @@ vectorizable_conversion (vec_info *vinfo, if ((code == FLOAT_EXPR && GET_MODE_SIZE (lhs_mode) > GET_MODE_SIZE (rhs_mode)) || (code == FIX_TRUNC_EXPR - && GET_MODE_SIZE (rhs_mode) > GET_MODE_SIZE (lhs_mode))) + && GET_MODE_SIZE (rhs_mode) > GET_MODE_SIZE (lhs_mode) + && !flag_trapping_math)) { bool float_expr_p = code == FLOAT_EXPR; scalar_mode imode = float_expr_p ? rhs_mode : lhs_mode; |