Re: [patch-2, rs6000] guard fctid on PPC64 and powerpc 476 [PR112707]

["Kewen.Lin" <linkw@linux.ibm.com>]

Hi Haochen,

on 2023/12/1 10:42, HAO CHEN GUI wrote:
> Hi,
>   The "fctid" is supported on 64-bit Power processors and powerpc 476. It
> need a guard to check it. The patch fixes the issue.
> 
>   Bootstrapped and tested on x86 and powerpc64-linux BE and LE with
> no regressions. Is this OK for trunk?
> 
> Thanks
> Gui Haochen
> 
> ChangeLog
> rs6000: guard fctid on PPC64 and powerpc 476
> 
> fctid is supported on 64-bit Power processors and powerpc 476. It should
> be guarded by this condition. The patch fixes the issue.
> 
> gcc/
> 	PR target/112707
> 	* config/rs6000/rs6000.h (TARGET_FCTID): Define.
> 	* config/rs6000/rs6000.md (lrint<mode>di2): Add guard TARGET_FCTID.
> 
> gcc/testsuite/
> 	PR target/112707
> 	* gcc.target/powerpc/pr112707.h: New.
> 	* gcc.target/powerpc/pr112707-2.c: New.
> 	* gcc.target/powerpc/pr112707-3.c: New.
> 
> 
> patch.diff
> diff --git a/gcc/config/rs6000/rs6000.h b/gcc/config/rs6000/rs6000.h
> index 22595f6..497ae3d 100644
> --- a/gcc/config/rs6000/rs6000.h
> +++ b/gcc/config/rs6000/rs6000.h
> @@ -467,6 +467,8 @@ extern int rs6000_vector_align[];
>  #define TARGET_FCFIDUS	TARGET_POPCNTD
>  #define TARGET_FCTIDUZ	TARGET_POPCNTD
>  #define TARGET_FCTIWUZ	TARGET_POPCNTD
> +/* Enable fctid on ppc64 and powerpc476.  */
> +#define TARGET_FCTID	(TARGET_POWERPC64 | TARGET_FPRND)

Like some existing macros which are checking rs6000_cpu, I think it's
more specific to check with PROCESSOR_PPC476, that is: rs6000_cpu ==
PROCESSOR_PPC476.  And say something like: "Only powerpc64 and powerpc476
support fctid." instead?

>  #define TARGET_CTZ	TARGET_MODULO
>  #define TARGET_EXTSWSLI	(TARGET_MODULO && TARGET_POWERPC64)
>  #define TARGET_MADDLD	TARGET_MODULO
> diff --git a/gcc/config/rs6000/rs6000.md b/gcc/config/rs6000/rs6000.md
> index d4337ce..4a5e63c 100644
> --- a/gcc/config/rs6000/rs6000.md
> +++ b/gcc/config/rs6000/rs6000.md
> @@ -6718,7 +6718,7 @@ (define_insn "lrint<mode>di2"
>    [(set (match_operand:DI 0 "gpc_reg_operand" "=d")
>  	(unspec:DI [(match_operand:SFDF 1 "gpc_reg_operand" "<rreg2>")]
>  		   UNSPEC_FCTID))]
> -  "TARGET_HARD_FLOAT"
> +  "TARGET_HARD_FLOAT && TARGET_FCTID"
>    "fctid %0,%1"
>    [(set_attr "type" "fp")])
> 
> diff --git a/gcc/testsuite/gcc.target/powerpc/pr112707-2.c b/gcc/testsuite/gcc.target/powerpc/pr112707-2.c
> new file mode 100644
> index 0000000..ae91913
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/powerpc/pr112707-2.c
> @@ -0,0 +1,6 @@
> +/* { dg-do compile { target { powerpc*-*-* && be } } } */

Nit: powerpc*-*-* && be checks are useless as ilp32 excludes le.

> +/* { dg-options "-O2 -mdejagnu-cpu=7450 -m32 -fno-math-errno" } */

Nit: -m32 isn't required.

> +/* { dg-require-effective-target ilp32 } */> +/* { dg-final { scan-assembler-not {\mfctid\M} } }  */
> +
> +#include "pr112707.h"
> diff --git a/gcc/testsuite/gcc.target/powerpc/pr112707-3.c b/gcc/testsuite/gcc.target/powerpc/pr112707-3.c
> new file mode 100644
> index 0000000..e47ce20
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/powerpc/pr112707-3.c
> @@ -0,0 +1,9 @@
> +/* { dg-do compile { target { powerpc*-*-* && be } } } */
> +/* { dg-options "-O2 -m32 -fno-math-errno -mdejagnu-cpu=476fp" } */

Likewise.

The others look good to me, thanks!

BR,
Kewen

> +/* { dg-require-effective-target ilp32 } */
> +
> +/* powerpc 476fp has hard float enabled which is required by fctid */
> +
> +#include "pr112707.h"
> +
> +/* { dg-final { scan-assembler-times {\mfctid\M} 2 } } */
> diff --git a/gcc/testsuite/gcc.target/powerpc/pr112707.h b/gcc/testsuite/gcc.target/powerpc/pr112707.h
> new file mode 100644
> index 0000000..e427dc6
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/powerpc/pr112707.h
> @@ -0,0 +1,10 @@
> +long long test1 (double a)
> +{
> +  return __builtin_llrint (a);
> +}
> +
> +long long test2 (float a)
> +{
> +  return __builtin_llrint (a);
> +}
> +