On Wed, Jan 27, 2021 at 03:22:45PM +0800, Hongtao Liu wrote:
> Hi：
> As desribed in PR, also remove the relevant and useless expanders
> and builtins, the user can
> directly use == and >, without calling the builtin function.
> Bootstrapped and regtested on x86_64-linux-gnu{-m32,}.
>
> gcc/ChangeLog:
>
> PR target/98833
> * config/i386/i386-builtin.def (BDESC): Delete
> __builtin_ia32_pcmpeqb128, __builtin_ia32_pcmpeqw128,
> __builtin_ia32_pcmpeqd128, __builtin_ia32_pcmpgtb128,
> __builtin_ia32_pcmpgtw128, __builtin_ia32_pcmpgtd128,
> __builtin_ia32_pcmpeqb256, __builtin_ia32_pcmpeqw256,
> __builtin_ia32_pcmpeqd256, __builtin_ia32_pcmpeqq256,
> __builtin_ia32_pcmpgtb256, __builtin_ia32_pcmpgtw256,
> __builtin_ia32_pcmpgtd256, __builtin_ia32_pcmpgtq256.
> * config/i386/sse.md (avx2_eq<mode>3): Deleted.
> (sse2_eq<mode>3): Ditto.
> (sse2_gt<mode>3): Renamed to ..
> (*sse2_gt<mode>3): And drop !TARGET_XOP in condition.
> (*sse2_eq<mode>3): Drop !TARGET_XOP in condition.
>
> gcc/testsuite/ChangeLog:
>
> PR target/98833
> * gcc.target/i386/pr98833.c: New test.
>
> libcpp/
>
> PR target/98833
> * lex.c (search_line_sse2): Replace builtins with == operator.
Oops, I wasn't aware of the libcpp use, I'm afraid that means we should
reconsider removing the builtins, because that means that e.g.
GCC 10 will not build with GCC 11 as system compiler anymore, people
bisecting GCC changes will have troubles etc.
And a codesearch seems to show that other projects do use these builtins
(even the AVX2 ones) too :(.
I think the libcpp/ change is ok, as we've bumped minimum GCC version
for building GCC to GCC 4.8 in GCC 11. Note that GCC 4.7 in C++
doesn't handle the == operators:
error: invalid operands of types ‘v16qi {aka __vector(16) char}’ and ‘v16qi
{aka __vector(16) char}’ to binary ‘operator==’
but 4.8 seems to work fine already.
But, can we perhaps keep the builtins, but fold them immediately in
ix86_gimple_fold_builtin so that we don't need the named patterns?
Though, I guess that we could defer those changes to GCC 12.
So can you just drop the !TARGET_XOP from conditions, add testcase and
change libcpp/ for GCC 11 and do the rest for GCC 12?
Thanks.
Jakub
