On Sun, 2022-11-06 at 09:57 +0800, Lulu Cheng wrote:
>
> 在 2022/11/4 下午10:37, Xi Ruoyao 写道:
> > Add fcopysign.{s,d} with the names copysign{sf,df}3 so GCC will expand
> > __builtin_copysign{f,} to a single instruction.
> >
> > Link: https://sourceware.org/pipermail/libc-alpha/2022-November/143177.html
> >
> > gcc/ChangeLog:
> >
> > * config/loongarch/loongarch.md (UNSPEC_FCOPYSIGN): New unspec.
> > (type): Add fcopysign.
> > (copysign<mode>3): New instruction template.
> >
> > gcc/testsuite/ChangeLog:
> >
> > * gcc.target/loongarch/fcopysign.c: New test.
> > ---
> >
> > Bootstrapped and regtested on loongarch64-linux-gnu. Ok for trunk?
> >
> > gcc/config/loongarch/loongarch.md | 22 ++++++++++++++++++-
> > .../gcc.target/loongarch/fcopysign.c | 16 ++++++++++++++
> > 2 files changed, 37 insertions(+), 1 deletion(-)
> > create mode 100644 gcc/testsuite/gcc.target/loongarch/fcopysign.c
> >
> > diff --git a/gcc/config/loongarch/loongarch.md
> > b/gcc/config/loongarch/loongarch.md
> > index 214b14bddd3..042e6e74491 100644
> > --- a/gcc/config/loongarch/loongarch.md
> > +++ b/gcc/config/loongarch/loongarch.md
> > @@ -37,6 +37,7 @@ (define_c_enum "unspec" [
> > UNSPEC_FCLASS
> > UNSPEC_FMAX
> > UNSPEC_FMIN
> > + UNSPEC_FCOPYSIGN
> >
> > ;; Override return address for exception handling.
> > UNSPEC_EH_RETURN
> > @@ -214,6 +215,7 @@ (define_attr "qword_mode" "no,yes"
> > ;; fabs floating point absolute value
> > ;; fneg floating point negation
> > ;; fcmp floating point compare
> > +;; fcopysign floating point copysign
> > ;; fcvt floating point convert
> > ;; fsqrt floating point square root
> > ;; frsqrt floating point reciprocal square root
> > @@ -226,7 +228,7 @@ (define_attr "type"
> >
> > "unknown,branch,jump,call,load,fpload,fpidxload,store,fpstore,fpidxstore,
> > prefetch,prefetchx,condmove,mgtf,mftg,const,arith,logical,
> > shift,slt,signext,clz,trap,imul,idiv,move,
> > - fmove,fadd,fmul,fmadd,fdiv,frdiv,fabs,fneg,fcmp,fcvt,fsqrt,
> > + fmove,fadd,fmul,fmadd,fdiv,frdiv,fabs,fneg,fcmp,fcopysign,fcvt,fsqrt,
> > frsqrt,accext,accmod,multi,atomic,syncloop,nop,ghost"
> > (cond [(eq_attr "jirl" "!unset") (const_string "call")
> > (eq_attr "got" "load") (const_string "load")
> > @@ -976,6 +978,24 @@ (define_insn "abs<mode>2"
> > (set_attr "mode" "<UNITMODE>")])
> >
> > ;;
> > +;; ....................
> > +;;
> > +;; FLOATING POINT COPYSIGN
> > +;;
> > +;; ....................
> > +
> > +(define_insn "copysign<mode>3"
> > + [(set (match_operand:ANYF 0 "register_operand" "=f")
> > + (unspec:ANYF [(match_operand:ANYF 1 "register_operand" "f")
> > + (match_operand:ANYF 2 "register_operand" "f")]
> > + UNSPEC_FCOPYSIGN))]
> > + ""
>
> We need to add "TARGET_HARD_FLOAT" here.
It seems not strictly needed because ANYF expands to nothing if
!TARGET_HARD_FLOAT. We also don't have an explicit TARGET_HARD_FLOAT in
fadd.{s,d} etc.
But I agree that adding it improves the readability.
>
> Otherwise LGTM.
>
>
> Thanks!
--
Xi Ruoyao <xry...@xry111.site>
School of Aerospace Science and Technology, Xidian University
