On Wed, May 15, 2024 at 9:43 AM Kong, Lingling <lingling.k...@intel.com> wrote: > > From: Hongyu Wang <hongyu.w...@intel.com> > > APX NF(no flags) feature implements suppresses the update of status flags for > arithmetic operations. > > For NF add, it is not clear whether NF add can be faster than lea. If so, the > pattern needs to be adjusted to prefer LEA generation. > > gcc/ChangeLog: > > * config/i386/i386-opts.h (enum apx_features): Add nf > enumeration. > * config/i386/i386.h (TARGET_APX_NF): New. > * config/i386/i386.md (*add<mode>_1_nf): New define_insn. > * config/i386/i386.opt: Add apx_nf enumeration. > > gcc/testsuite/ChangeLog: > > * gcc.target/i386/apx-ndd.c: Fixed test. > * gcc.target/i386/apx-nf.c: New test. > > Co-authored-by: Lingling Kong <lingling.k...@intel.com> > > Bootstrapped and regtested on x86_64-linux-gnu. And Supported SPEC 2017 run > normally on Intel software development emulator. > Ok for trunk? > > --- > gcc/config/i386/i386-opts.h | 3 +- > gcc/config/i386/i386.h | 1 + > gcc/config/i386/i386.md | 42 +++++++++++++++++++++++++ > gcc/config/i386/i386.opt | 3 ++ > gcc/testsuite/gcc.target/i386/apx-ndd.c | 2 +- > gcc/testsuite/gcc.target/i386/apx-nf.c | 6 ++++ > 6 files changed, 55 insertions(+), 2 deletions(-) create mode 100644 > gcc/testsuite/gcc.target/i386/apx-nf.c > > diff --git a/gcc/config/i386/i386-opts.h b/gcc/config/i386/i386-opts.h index > ef2825803b3..60176ce609f 100644 > --- a/gcc/config/i386/i386-opts.h > +++ b/gcc/config/i386/i386-opts.h > @@ -140,7 +140,8 @@ enum apx_features { > apx_push2pop2 = 1 << 1, > apx_ndd = 1 << 2, > apx_ppx = 1 << 3, > - apx_all = apx_egpr | apx_push2pop2 | apx_ndd | apx_ppx, > + apx_nf = 1<< 4, > + apx_all = apx_egpr | apx_push2pop2 | apx_ndd | apx_ppx | apx_nf, > }; > > #endif > diff --git a/gcc/config/i386/i386.h b/gcc/config/i386/i386.h index > 529edff93a4..f20ae4726da 100644 > --- a/gcc/config/i386/i386.h > +++ b/gcc/config/i386/i386.h > @@ -55,6 +55,7 @@ see the files COPYING3 and COPYING.RUNTIME respectively. > If not, see #define TARGET_APX_PUSH2POP2 (ix86_apx_features & apx_push2pop2) > #define TARGET_APX_NDD (ix86_apx_features & apx_ndd) #define TARGET_APX_PPX > (ix86_apx_features & apx_ppx) > +#define TARGET_APX_NF (ix86_apx_features & apx_nf) > > #include "config/vxworks-dummy.h" > > diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md index > 764bfe20ff2..4a9e35c4990 100644 > --- a/gcc/config/i386/i386.md > +++ b/gcc/config/i386/i386.md > @@ -6233,6 +6233,48 @@ > } > }) > > > +;; NF instructions. > + > +(define_insn "*add<mode>_1_nf" > + [(set (match_operand:SWI 0 "nonimmediate_operand" "=rm,rje,r,r,r,r,r,r") > + (plus:SWI > + (match_operand:SWI 1 "nonimmediate_operand" "%0,0,0,r,r,rje,jM,r") > + (match_operand:SWI 2 "x86_64_general_operand" > +"r,e,BM,0,le,r,e,BM")))] > + "TARGET_APX_NF && > + ix86_binary_operator_ok (PLUS, <MODE>mode, operands, > + TARGET_APX_NDD)"
I wonder if we can use "define_subst" to conditionally add flags clobber for !TARGET_APX_NF targets. Even the example for "Define Subst" uses the insn w/ and w/o the clobber, so I think it is worth considering this approach. Uros.