On Tue, Oct 24, 2023 at 6:10 PM Richard Sandiford
<richard.sandif...@arm.com> wrote:
>
> The files changed in this patch had tests for masked and unmasked
> popcnt. However, the mask inputs to the masked forms were undefined,
> and would be set to zero by init_regs. Any combine-like pass that
> ran after init_regs could then fold the masked forms into the
> unmasked ones. I saw this while testing the late-combine pass
> on x86.
>
> Tested on x86_64-linux-gnu. OK to install? (I didn't think this
> counted as obvious because there are other ways of initialising
> the mask.)
Maybe just move the definition of the mask outside of the functions as
extern __mmask16 msk;
But of course your approach is also ok, so either way is ok with me.
>
> Richard
>
>
> gcc/testsuite/
> * gcc.target/i386/avx512bitalg-vpopcntb.c: Use an asm to define
> the mask.
> * gcc.target/i386/avx512bitalg-vpopcntbvl.c: Likewise.
> * gcc.target/i386/avx512bitalg-vpopcntw.c: Likewise.
> * gcc.target/i386/avx512bitalg-vpopcntwvl.c: Likewise.
> * gcc.target/i386/avx512vpopcntdq-vpopcntd.c: Likewise.
> * gcc.target/i386/avx512vpopcntdq-vpopcntq.c: Likewise.
> ---
> gcc/testsuite/gcc.target/i386/avx512bitalg-vpopcntb.c | 1 +
> gcc/testsuite/gcc.target/i386/avx512bitalg-vpopcntbvl.c | 1 +
> gcc/testsuite/gcc.target/i386/avx512bitalg-vpopcntw.c | 1 +
> gcc/testsuite/gcc.target/i386/avx512bitalg-vpopcntwvl.c | 1 +
> gcc/testsuite/gcc.target/i386/avx512vpopcntdq-vpopcntd.c | 1 +
> gcc/testsuite/gcc.target/i386/avx512vpopcntdq-vpopcntq.c | 1 +
> 6 files changed, 6 insertions(+)
>
> diff --git a/gcc/testsuite/gcc.target/i386/avx512bitalg-vpopcntb.c
> b/gcc/testsuite/gcc.target/i386/avx512bitalg-vpopcntb.c
> index 44b82c0519d..c52088161a0 100644
> --- a/gcc/testsuite/gcc.target/i386/avx512bitalg-vpopcntb.c
> +++ b/gcc/testsuite/gcc.target/i386/avx512bitalg-vpopcntb.c
> @@ -11,6 +11,7 @@ extern __m512i z, z1;
> int foo ()
> {
> __mmask16 msk;
> + asm volatile ("" : "=k" (msk));
> __m512i c = _mm512_popcnt_epi8 (z);
> asm volatile ("" : "+v" (c));
> c = _mm512_mask_popcnt_epi8 (z1, msk, z);
> diff --git a/gcc/testsuite/gcc.target/i386/avx512bitalg-vpopcntbvl.c
> b/gcc/testsuite/gcc.target/i386/avx512bitalg-vpopcntbvl.c
> index 8c2dfaba9c6..7d11c6c4623 100644
> --- a/gcc/testsuite/gcc.target/i386/avx512bitalg-vpopcntbvl.c
> +++ b/gcc/testsuite/gcc.target/i386/avx512bitalg-vpopcntbvl.c
> @@ -16,6 +16,7 @@ int foo ()
> {
> __mmask32 msk32;
> __mmask16 msk16;
> + asm volatile ("" : "=k" (msk16), "=k" (msk32));
> __m256i c256 = _mm256_popcnt_epi8 (y);
> asm volatile ("" : "+v" (c256));
> c256 = _mm256_mask_popcnt_epi8 (y_1, msk32, y);
> diff --git a/gcc/testsuite/gcc.target/i386/avx512bitalg-vpopcntw.c
> b/gcc/testsuite/gcc.target/i386/avx512bitalg-vpopcntw.c
> index 2ef8589f6c1..bc470415e9b 100644
> --- a/gcc/testsuite/gcc.target/i386/avx512bitalg-vpopcntw.c
> +++ b/gcc/testsuite/gcc.target/i386/avx512bitalg-vpopcntw.c
> @@ -11,6 +11,7 @@ extern __m512i z, z1;
> int foo ()
> {
> __mmask16 msk;
> + asm volatile ("" : "=k" (msk));
> __m512i c = _mm512_popcnt_epi16 (z);
> asm volatile ("" : "+v" (c));
> c = _mm512_mask_popcnt_epi16 (z1, msk, z);
> diff --git a/gcc/testsuite/gcc.target/i386/avx512bitalg-vpopcntwvl.c
> b/gcc/testsuite/gcc.target/i386/avx512bitalg-vpopcntwvl.c
> index c976461b12e..3a6af3ed8a1 100644
> --- a/gcc/testsuite/gcc.target/i386/avx512bitalg-vpopcntwvl.c
> +++ b/gcc/testsuite/gcc.target/i386/avx512bitalg-vpopcntwvl.c
> @@ -16,6 +16,7 @@ int foo ()
> {
> __mmask16 msk16;
> __mmask8 msk8;
> + asm volatile ("" : "=k" (msk16), "=k" (msk8));
> __m256i c256 = _mm256_popcnt_epi16 (y);
> asm volatile ("" : "+v" (c256));
> c256 = _mm256_mask_popcnt_epi16 (y_1, msk16, y);
> diff --git a/gcc/testsuite/gcc.target/i386/avx512vpopcntdq-vpopcntd.c
> b/gcc/testsuite/gcc.target/i386/avx512vpopcntdq-vpopcntd.c
> index b4d82f97032..0a54ae83055 100644
> --- a/gcc/testsuite/gcc.target/i386/avx512vpopcntdq-vpopcntd.c
> +++ b/gcc/testsuite/gcc.target/i386/avx512vpopcntdq-vpopcntd.c
> @@ -20,6 +20,7 @@ int foo ()
> {
> __mmask16 msk;
> __mmask8 msk8;
> + asm volatile ("" : "=k" (msk), "=k" (msk8));
> __m128i a = _mm_popcnt_epi32 (x);
> asm volatile ("" : "+v" (a));
> a = _mm_mask_popcnt_epi32 (x_1, msk8, x);
> diff --git a/gcc/testsuite/gcc.target/i386/avx512vpopcntdq-vpopcntq.c
> b/gcc/testsuite/gcc.target/i386/avx512vpopcntdq-vpopcntq.c
> index e87d6c999b6..c11e6e00998 100644
> --- a/gcc/testsuite/gcc.target/i386/avx512vpopcntdq-vpopcntq.c
> +++ b/gcc/testsuite/gcc.target/i386/avx512vpopcntdq-vpopcntq.c
> @@ -19,6 +19,7 @@ extern __m512i z, z_1;
> int foo ()
> {
> __mmask8 msk;
> + asm volatile ("" : "=k" (msk));
> __m128i a = _mm_popcnt_epi64 (x);
> asm volatile ("" : "+v" (a));
> a = _mm_mask_popcnt_epi64 (x_1, msk, x);
> --
> 2.25.1
>
--
BR,
Hongtao
