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author | Jakub Jelinek <jakub@redhat.com> | 2023-01-31 09:20:34 +0100 |
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committer | Jakub Jelinek <jakub@redhat.com> | 2023-01-31 09:20:34 +0100 |
commit | 41602390456901c14ecdfa2fa64c3cebd5b6ff09 (patch) | |
tree | 3ebbe3ba0129daf2658325eafbec3e07556e98f3 | |
parent | a190f583050630802438bce9aa854fdfa7a4433c (diff) | |
download | gcc-41602390456901c14ecdfa2fa64c3cebd5b6ff09.zip gcc-41602390456901c14ecdfa2fa64c3cebd5b6ff09.tar.gz gcc-41602390456901c14ecdfa2fa64c3cebd5b6ff09.tar.bz2 |
i386: Fix up -Wuninitialized warnings in avx512erintrin.h [PR105593]
As reported in the PR, there are some -Wuninitialized warnings in
avx512erintrin.h. One can see that by compiling sse-23.c testcase with
-Wuninitialized (or when actually using those intrinsics).
Those 6 spots use an uninitialized variable and pass it as one of the
argument to a builtin with constant mask -1, because there is no unmasked
builtin. It is true that expansion of those builtins into RTL will see
mask is all ones and ignore the unneeded argument, but -Wuninitialized
is diagnosed on GIMPLE and on GIMPLE these builtins are just builtin calls.
avx512fintrin.h and other headers use in these cases the _mm*_undefined_* ()
intrinsics, like:
return (__m512i) __builtin_ia32_psrav8di_mask ((__v8di) __X,
(__v8di) __Y,
(__v8di)
_mm512_undefined_epi32 (),
(__mmask8) -1);
etc. and the following patch does the same for avx512erintrin.h.
With the recent changes in C++ FE and the _mm*_undefined_* intrinsics,
we don't emit -Wuninitialized warnings for those (previously we didn't
just in C due to self-initialization). Of course we could also
just self-initialize these uninitialized vars and add the #pragma GCC
diagnostic dances around it, but using the intrinsics is consistent with
the rest and IMHO cleaner.
2023-01-31 Jakub Jelinek <jakub@redhat.com>
PR c++/105593
* config/i386/avx512erintrin.h (_mm512_exp2a23_round_pd,
_mm512_exp2a23_round_ps, _mm512_rcp28_round_pd, _mm512_rcp28_round_ps,
_mm512_rsqrt28_round_pd, _mm512_rsqrt28_round_ps): Use
_mm512_undefined_pd () or _mm512_undefined_ps () instead of using
uninitialized automatic variable __W.
* gcc.target/i386/sse-23.c: Add -Wuninitialized to dg-options.
-rw-r--r-- | gcc/config/i386/avx512erintrin.h | 18 | ||||
-rw-r--r-- | gcc/testsuite/gcc.target/i386/sse-23.c | 2 |
2 files changed, 7 insertions, 13 deletions
diff --git a/gcc/config/i386/avx512erintrin.h b/gcc/config/i386/avx512erintrin.h index 7d6aecb..bd83b7f 100644 --- a/gcc/config/i386/avx512erintrin.h +++ b/gcc/config/i386/avx512erintrin.h @@ -51,9 +51,8 @@ extern __inline __m512d __attribute__ ((__gnu_inline__, __always_inline__, __artificial__)) _mm512_exp2a23_round_pd (__m512d __A, int __R) { - __m512d __W; return (__m512d) __builtin_ia32_exp2pd_mask ((__v8df) __A, - (__v8df) __W, + (__v8df) _mm512_undefined_pd (), (__mmask8) -1, __R); } @@ -79,9 +78,8 @@ extern __inline __m512 __attribute__ ((__gnu_inline__, __always_inline__, __artificial__)) _mm512_exp2a23_round_ps (__m512 __A, int __R) { - __m512 __W; return (__m512) __builtin_ia32_exp2ps_mask ((__v16sf) __A, - (__v16sf) __W, + (__v16sf) _mm512_undefined_ps (), (__mmask16) -1, __R); } @@ -107,9 +105,8 @@ extern __inline __m512d __attribute__ ((__gnu_inline__, __always_inline__, __artificial__)) _mm512_rcp28_round_pd (__m512d __A, int __R) { - __m512d __W; return (__m512d) __builtin_ia32_rcp28pd_mask ((__v8df) __A, - (__v8df) __W, + (__v8df) _mm512_undefined_pd (), (__mmask8) -1, __R); } @@ -135,9 +132,8 @@ extern __inline __m512 __attribute__ ((__gnu_inline__, __always_inline__, __artificial__)) _mm512_rcp28_round_ps (__m512 __A, int __R) { - __m512 __W; return (__m512) __builtin_ia32_rcp28ps_mask ((__v16sf) __A, - (__v16sf) __W, + (__v16sf) _mm512_undefined_ps (), (__mmask16) -1, __R); } @@ -229,9 +225,8 @@ extern __inline __m512d __attribute__ ((__gnu_inline__, __always_inline__, __artificial__)) _mm512_rsqrt28_round_pd (__m512d __A, int __R) { - __m512d __W; return (__m512d) __builtin_ia32_rsqrt28pd_mask ((__v8df) __A, - (__v8df) __W, + (__v8df) _mm512_undefined_pd (), (__mmask8) -1, __R); } @@ -257,9 +252,8 @@ extern __inline __m512 __attribute__ ((__gnu_inline__, __always_inline__, __artificial__)) _mm512_rsqrt28_round_ps (__m512 __A, int __R) { - __m512 __W; return (__m512) __builtin_ia32_rsqrt28ps_mask ((__v16sf) __A, - (__v16sf) __W, + (__v16sf) _mm512_undefined_ps (), (__mmask16) -1, __R); } diff --git a/gcc/testsuite/gcc.target/i386/sse-23.c b/gcc/testsuite/gcc.target/i386/sse-23.c index 0f56e93..37cc2fd 100644 --- a/gcc/testsuite/gcc.target/i386/sse-23.c +++ b/gcc/testsuite/gcc.target/i386/sse-23.c @@ -1,5 +1,5 @@ /* { dg-do compile } */ -/* { dg-options "-O2 -Werror-implicit-function-declaration -march=k8" } */ +/* { dg-options "-O2 -Werror-implicit-function-declaration -Wuninitialized -march=k8" } */ /* { dg-add-options bind_pic_locally } */ #include <mm_malloc.h> |