On Sun, May 30, 2021 at 11:49 AM Jeff Law <jeffreya...@gmail.com> wrote: > > > > On 5/11/2021 5:35 PM, H.J. Lu via Gcc-patches wrote: > > Add TARGET_READ_MEMSET_VALUE and TARGET_GEN_MEMSET_VALUE to support > > target instructions to duplicate QImode value to TImode/OImode/XImode > > value for memmset. Define SCRATCH_SSE_REG as a scratch register for > > ix86_gen_memset_value. > > > > gcc/ > > > > PR middle-end/90773 > > * builtins.c (builtin_memset_read_str): Call > > targetm.read_memset_value. > > (builtin_memset_gen_str): Call targetm.gen_memset_value. > > * target.def (read_memset_value): New hook. > > (gen_memset_value): Likewise. > > * targhooks.c: Inclue "builtins.h". > > (default_read_memset_value): New function. > > (default_gen_memset_value): Likewise. > > * targhooks.h (default_read_memset_value): New prototype. > > (default_gen_memset_value): Likewise. > > * config/i386/i386-expand.c (ix86_expand_vector_init_duplicate): > > Make it global. > > * config/i386/i386-protos.h (ix86_minimum_incoming_stack_boundary): > > New. > > (ix86_expand_vector_init_duplicate): Likewise. > > * config/i386/i386.c (ix86_minimum_incoming_stack_boundary): Add > > an argument to ignore stack_alignment_estimated. It is passed > > as false by default. > > (ix86_gen_memset_value_from_prev): New function. > > (ix86_gen_memset_value): Likewise. > > (ix86_read_memset_value): Likewise. > > (TARGET_GEN_MEMSET_VALUE): New. > > (TARGET_READ_MEMSET_VALUE): Likewise. > > * config/i386/i386.h (SCRATCH_SSE_REG): New. > > * doc/tm.texi.in: Add TARGET_READ_MEMSET_VALUE and > > TARGET_GEN_MEMSET_VALUE hooks. > > * doc/tm.texi: Regenerated. > > > > gcc/testsuite/ > > > > PR middle-end/90773 > > * gcc.target/i386/pr90773-15.c: New test. > > * gcc.target/i386/pr90773-16.c: Likewise. > > * gcc.target/i386/pr90773-17.c: Likewise. > > * gcc.target/i386/pr90773-18.c: Likewise. > > * gcc.target/i386/pr90773-19.c: Likewise. > Why does this need target hooks? ISTM the right way to go here is to > just emit the constant load to the target register and let the target > figure out how best to construct the constant into the register. If > that means load it via QImode and broadcast, that's fine, but I'm not > sure why that's not all implemented in the target files. >
I will submit a patch to add optabs instead. Thanks. -- H.J.
