diff mbox series

[v2,4/4] LoongArch: Add flogb.{s, d} instructions and expand logb{sf, df}2

Message ID 20221109135329.952128-5-xry111@xry111.site
State Accepted
Headers
Series LoongArch: Add some floating-point operations |

Checks

Context Check Description
snail/gcc-patch-check success Github commit url

Commit Message

Xi Ruoyao Nov. 9, 2022, 1:53 p.m. UTC 
  On LoongArch, flogb instructions extract the exponent of a non-negative
floating point value, but produces NaN for negative values.  So we need
to add a fabs instruction when we expand logb.

gcc/ChangeLog:

	* config/loongarch/loongarch.md (UNSPEC_FLOGB): New unspec.
	(type): Add flogb.
	(logb_non_negative<mode>2): New instruction template.
	(logb<mode>2): New define_expand.

gcc/testsuite/ChangeLog:

	* gcc.target/loongarch/flogb.c: New test.
---
 gcc/config/loongarch/loongarch.md          | 35 ++++++++++++++++++++--
 gcc/testsuite/gcc.target/loongarch/flogb.c | 18 +++++++++++
 2 files changed, 51 insertions(+), 2 deletions(-)
 create mode 100644 gcc/testsuite/gcc.target/loongarch/flogb.c

Comments

chenglulu Nov. 12, 2022, 6:51 a.m. UTC | #1 
LGTM!

Thanks.

在 2022/11/9 下午9:53, Xi Ruoyao 写道:
> On LoongArch, flogb instructions extract the exponent of a non-negative
> floating point value, but produces NaN for negative values.  So we need
> to add a fabs instruction when we expand logb.
>
> gcc/ChangeLog:
>
> 	* config/loongarch/loongarch.md (UNSPEC_FLOGB): New unspec.
> 	(type): Add flogb.
> 	(logb_non_negative<mode>2): New instruction template.
> 	(logb<mode>2): New define_expand.
>
> gcc/testsuite/ChangeLog:
>
> 	* gcc.target/loongarch/flogb.c: New test.
> ---
>   gcc/config/loongarch/loongarch.md          | 35 ++++++++++++++++++++--
>   gcc/testsuite/gcc.target/loongarch/flogb.c | 18 +++++++++++
>   2 files changed, 51 insertions(+), 2 deletions(-)
>   create mode 100644 gcc/testsuite/gcc.target/loongarch/flogb.c
>
> diff --git a/gcc/config/loongarch/loongarch.md b/gcc/config/loongarch/loongarch.md
> index c141c9adde2..682ab961741 100644
> --- a/gcc/config/loongarch/loongarch.md
> +++ b/gcc/config/loongarch/loongarch.md
> @@ -42,6 +42,7 @@ (define_c_enum "unspec" [
>     UNSPEC_FTINTRM
>     UNSPEC_FTINTRP
>     UNSPEC_FSCALEB
> +  UNSPEC_FLOGB
>   
>     ;; Override return address for exception handling.
>     UNSPEC_EH_RETURN
> @@ -217,6 +218,7 @@ (define_attr "qword_mode" "no,yes"
>   ;; fdiv		floating point divide
>   ;; frdiv	floating point reciprocal divide
>   ;; fabs		floating point absolute value
> +;; flogb	floating point exponent extract
>   ;; fneg		floating point negation
>   ;; fcmp		floating point compare
>   ;; fcopysign	floating point copysign
> @@ -233,8 +235,8 @@ (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,fcopysign,fcvt,fscaleb,
> -   fsqrt,frsqrt,accext,accmod,multi,atomic,syncloop,nop,ghost"
> +   fmove,fadd,fmul,fmadd,fdiv,frdiv,fabs,flogb,fneg,fcmp,fcopysign,fcvt,
> +   fscaleb,fsqrt,frsqrt,accext,accmod,multi,atomic,syncloop,nop,ghost"
>     (cond [(eq_attr "jirl" "!unset") (const_string "call")
>   	 (eq_attr "got" "load") (const_string "load")
>   
> @@ -1039,6 +1041,35 @@ (define_insn "ldexp<mode>3"
>      (set_attr "mode" "<UNITMODE>")])
>   
>   ;;
> +;;  ....................
> +;;
> +;;	FLOATING POINT EXPONENT EXTRACT
> +;;
> +;;  ....................
> +
> +(define_insn "logb_non_negative<mode>2"
> +  [(set (match_operand:ANYF 0 "register_operand" "=f")
> +	(unspec:ANYF [(match_operand:ANYF 1 "register_operand" "f")]
> +		     UNSPEC_FLOGB))]
> +  "TARGET_HARD_FLOAT"
> +  "flogb.<fmt>\t%0,%1"
> +  [(set_attr "type" "flogb")
> +   (set_attr "mode" "<UNITMODE>")])
> +
> +(define_expand "logb<mode>2"
> +  [(set (match_operand:ANYF 0 "register_operand")
> +	(unspec:ANYF [(abs:ANYF (match_operand:ANYF 1 "register_operand"))]
> +		     UNSPEC_FLOGB))]
> +  "TARGET_HARD_FLOAT"
> +{
> +  rtx tmp = gen_reg_rtx (<MODE>mode);
> +
> +  emit_insn (gen_abs<mode>2 (tmp, operands[1]));
> +  emit_insn (gen_logb_non_negative<mode>2 (operands[0], tmp));
> +  DONE;
> +})
> +
> +;;
>   ;;  ...................
>   ;;
>   ;;  Count leading zeroes.
> diff --git a/gcc/testsuite/gcc.target/loongarch/flogb.c b/gcc/testsuite/gcc.target/loongarch/flogb.c
> new file mode 100644
> index 00000000000..1daefe54e13
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/loongarch/flogb.c
> @@ -0,0 +1,18 @@
> +/* { dg-do compile } */
> +/* { dg-options "-mdouble-float -fno-math-errno" } */
> +/* { dg-final { scan-assembler "fabs\\.s" } } */
> +/* { dg-final { scan-assembler "fabs\\.d" } } */
> +/* { dg-final { scan-assembler "flogb\\.s" } } */
> +/* { dg-final { scan-assembler "flogb\\.d" } } */
> +
> +double
> +my_logb (double a)
> +{
> +  return __builtin_logb (a);
> +}
> +
> +float
> +my_logbf (float a)
> +{
> +  return __builtin_logbf (a);
> +}
diff mbox series

Patch

diff --git a/gcc/config/loongarch/loongarch.md b/gcc/config/loongarch/loongarch.md
index c141c9adde2..682ab961741 100644
--- a/gcc/config/loongarch/loongarch.md
+++ b/gcc/config/loongarch/loongarch.md
@@ -42,6 +42,7 @@  (define_c_enum "unspec" [
   UNSPEC_FTINTRM
   UNSPEC_FTINTRP
   UNSPEC_FSCALEB
+  UNSPEC_FLOGB
 
   ;; Override return address for exception handling.
   UNSPEC_EH_RETURN
@@ -217,6 +218,7 @@  (define_attr "qword_mode" "no,yes"
 ;; fdiv		floating point divide
 ;; frdiv	floating point reciprocal divide
 ;; fabs		floating point absolute value
+;; flogb	floating point exponent extract
 ;; fneg		floating point negation
 ;; fcmp		floating point compare
 ;; fcopysign	floating point copysign
@@ -233,8 +235,8 @@  (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,fcopysign,fcvt,fscaleb,
-   fsqrt,frsqrt,accext,accmod,multi,atomic,syncloop,nop,ghost"
+   fmove,fadd,fmul,fmadd,fdiv,frdiv,fabs,flogb,fneg,fcmp,fcopysign,fcvt,
+   fscaleb,fsqrt,frsqrt,accext,accmod,multi,atomic,syncloop,nop,ghost"
   (cond [(eq_attr "jirl" "!unset") (const_string "call")
 	 (eq_attr "got" "load") (const_string "load")
 
@@ -1039,6 +1041,35 @@  (define_insn "ldexp<mode>3"
    (set_attr "mode" "<UNITMODE>")])
 
 ;;
+;;  ....................
+;;
+;;	FLOATING POINT EXPONENT EXTRACT
+;;
+;;  ....................
+
+(define_insn "logb_non_negative<mode>2"
+  [(set (match_operand:ANYF 0 "register_operand" "=f")
+	(unspec:ANYF [(match_operand:ANYF 1 "register_operand" "f")]
+		     UNSPEC_FLOGB))]
+  "TARGET_HARD_FLOAT"
+  "flogb.<fmt>\t%0,%1"
+  [(set_attr "type" "flogb")
+   (set_attr "mode" "<UNITMODE>")])
+
+(define_expand "logb<mode>2"
+  [(set (match_operand:ANYF 0 "register_operand")
+	(unspec:ANYF [(abs:ANYF (match_operand:ANYF 1 "register_operand"))]
+		     UNSPEC_FLOGB))]
+  "TARGET_HARD_FLOAT"
+{
+  rtx tmp = gen_reg_rtx (<MODE>mode);
+
+  emit_insn (gen_abs<mode>2 (tmp, operands[1]));
+  emit_insn (gen_logb_non_negative<mode>2 (operands[0], tmp));
+  DONE;
+})
+
+;;
 ;;  ...................
 ;;
 ;;  Count leading zeroes.
diff --git a/gcc/testsuite/gcc.target/loongarch/flogb.c b/gcc/testsuite/gcc.target/loongarch/flogb.c
new file mode 100644
index 00000000000..1daefe54e13
--- /dev/null
+++ b/gcc/testsuite/gcc.target/loongarch/flogb.c
@@ -0,0 +1,18 @@ 
+/* { dg-do compile } */
+/* { dg-options "-mdouble-float -fno-math-errno" } */
+/* { dg-final { scan-assembler "fabs\\.s" } } */
+/* { dg-final { scan-assembler "fabs\\.d" } } */
+/* { dg-final { scan-assembler "flogb\\.s" } } */
+/* { dg-final { scan-assembler "flogb\\.d" } } */
+
+double
+my_logb (double a)
+{
+  return __builtin_logb (a);
+}
+
+float
+my_logbf (float a)
+{
+  return __builtin_logbf (a);
+}