Hi Claudio,
> On 25 Jul 2024, at 16:25, Claudio Bantaloukas <claudio.bantalou...@arm.com>
> wrote:
>
> External email: Use caution opening links or attachments
>
>
> The ACLE declares several helper types and functions to
> facilitate construction of `fpm` arguments.
>
> gcc/ChangeLog:
>
> * config/aarch64/arm_acle.h (fpm_t): New type representing fpmr values.
> (enum __ARM_FPM_FORMAT): New enum representing valid fp8 formats.
> (enum __ARM_FPM_OVERFLOW): New enum representing how some fp8
> calculations work.
> (arm_fpm_init): New.
> (arm_set_fpm_src1_format): Likewise.
> (arm_set_fpm_src2_format): Likewise.
> (arm_set_fpm_dst_format): Likewise.
> (arm_set_fpm_overflow_cvt): Likewise.
> (arm_set_fpm_overflow_mul): Likewise.
> (arm_set_fpm_lscale): Likewise.
> (arm_set_fpm_lscale2): Likewise.
> (arm_set_fpm_nscale): Likewise.
>
Thanks for the updates, these ChangeLog entries should now be updated to
reflect the names.
One question I just asked on the ACLE PR for FP8, are these helpers supposed to
be defined in arm_acle.h? I think it’s reasonable, but I didn’t see explicit
wording for it in ACLE so I’d like to clarify.
Thanks,
Kyrill
> gcc/testsuite/ChangeLog:
>
> * gcc.target/aarch64/acle/fp8-helpers.c: New test of fpmr helper
> functions.
> ---
> gcc/config/aarch64/arm_acle.h | 33 ++++++++++++
> .../gcc.target/aarch64/acle/fp8-helpers.c | 52 +++++++++++++++++++
> 2 files changed, 85 insertions(+)
> create mode 100644 gcc/testsuite/gcc.target/aarch64/acle/fp8-helpers.c
>
> diff --git a/gcc/config/aarch64/arm_acle.h b/gcc/config/aarch64/arm_acle.h
> index 2aa681090fa..fd4fa855b90 100644
> --- a/gcc/config/aarch64/arm_acle.h
> +++ b/gcc/config/aarch64/arm_acle.h
> @@ -385,6 +385,39 @@ __rndrrs (uint64_t *__res)
>
> #pragma GCC pop_options
>
> +typedef uint64_t fpm_t;
> +
> +enum __ARM_FPM_FORMAT
> +{
> + __ARM_FPM_E5M2,
> + __ARM_FPM_E4M3,
> +};
> +
> +enum __ARM_FPM_OVERFLOW
> +{
> + __ARM_FPM_INFNAN,
> + __ARM_FPM_SATURATE,
> +};
> +
> +#define __arm_fpm_init() (0)
> +
> +#define __arm_set_fpm_src1_format(__fpm, __format) \
> + ((__fpm & ~(uint64_t)0x7) | (__format & (uint64_t)0x7))
> +#define __arm_set_fpm_src2_format(__fpm, __format) \
> + ((__fpm & ~((uint64_t)0x7 << 3)) | ((__format & (uint64_t)0x7) << 3))
> +#define __arm_set_fpm_dst_format(__fpm, __format) \
> + ((__fpm & ~((uint64_t)0x7 << 6)) | ((__format & (uint64_t)0x7) << 6))
> +#define __arm_set_fpm_overflow_cvt(__fpm, __behaviour) \
> + ((__fpm & ~((uint64_t)0x1 << 15)) | ((__behaviour & (uint64_t)0x1) << 15))
> +#define __arm_set_fpm_overflow_mul(__fpm, __behaviour) \
> + ((__fpm & ~((uint64_t)0x1 << 14)) | ((__behaviour & (uint64_t)0x1) << 14))
> +#define __arm_set_fpm_lscale(__fpm, __scale) \
> + ((__fpm & ~((uint64_t)0x7f << 16)) | ((__scale & (uint64_t)0x7f) << 16))
> +#define __arm_set_fpm_lscale2(__fpm, __scale) \
> + ((__fpm & ~((uint64_t)0x3f << 32)) | ((__scale & (uint64_t)0x3f) << 32))
> +#define __arm_set_fpm_nscale(__fpm, __scale) \
> + ((__fpm & ~((uint64_t)0xff << 24)) | ((__scale & (uint64_t)0xff) << 24))
> +
> #ifdef __cplusplus
> }
> #endif
> diff --git a/gcc/testsuite/gcc.target/aarch64/acle/fp8-helpers.c
> b/gcc/testsuite/gcc.target/aarch64/acle/fp8-helpers.c
> new file mode 100644
> index 00000000000..e235c3621d1
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/aarch64/acle/fp8-helpers.c
> @@ -0,0 +1,52 @@
> +/* Test the fp8 ACLE helper functions. */
> +/* { dg-do compile } */
> +/* { dg-options "-std=c90 -pedantic-errors -O1 -march=armv9.4-a+fp8" } */
> +
> +#include <arm_acle.h>
> +
> +void
> +test_prepare_fpmr_sysreg ()
> +{
> +
> +#define _S_EQ(expr, expected)
> \
> + _Static_assert (expr == expected, #expr " == " #expected)
> +
> + _S_EQ (__arm_fpm_init (), 0);
> +
> + /* Bits [2:0] */
> + _S_EQ (__arm_set_fpm_src1_format (__arm_fpm_init (), __ARM_FPM_E5M2), 0);
> + _S_EQ (__arm_set_fpm_src1_format (__arm_fpm_init (), __ARM_FPM_E4M3), 0x1);
> +
> + /* Bits [5:3] */
> + _S_EQ (__arm_set_fpm_src2_format (__arm_fpm_init (), __ARM_FPM_E5M2), 0);
> + _S_EQ (__arm_set_fpm_src2_format (__arm_fpm_init (), __ARM_FPM_E4M3), 0x8);
> +
> + /* Bits [8:6] */
> + _S_EQ (__arm_set_fpm_dst_format (__arm_fpm_init (), __ARM_FPM_E5M2), 0);
> + _S_EQ (__arm_set_fpm_dst_format (__arm_fpm_init (), __ARM_FPM_E4M3), 0x40);
> +
> + /* Bit 14 */
> + _S_EQ (__arm_set_fpm_overflow_mul (__arm_fpm_init (), __ARM_FPM_INFNAN),
> 0);
> + _S_EQ (__arm_set_fpm_overflow_mul (__arm_fpm_init (), __ARM_FPM_SATURATE),
> + 0x4000);
> +
> + /* Bit 15 */
> + _S_EQ (__arm_set_fpm_overflow_cvt (__arm_fpm_init (), __ARM_FPM_INFNAN),
> 0);
> + _S_EQ (__arm_set_fpm_overflow_cvt (__arm_fpm_init (), __ARM_FPM_SATURATE),
> + 0x8000);
> +
> + /* Bits [22:16] */
> + _S_EQ (__arm_set_fpm_lscale (__arm_fpm_init (), 0), 0);
> + _S_EQ (__arm_set_fpm_lscale (__arm_fpm_init (), 127), 0x7F0000);
> +
> + /* Bits [37:32] */
> + _S_EQ (__arm_set_fpm_lscale2 (__arm_fpm_init (), 0), 0);
> + _S_EQ (__arm_set_fpm_lscale2 (__arm_fpm_init (), 63), 0x3F00000000);
> +
> + /* Bits [31:24] */
> + _S_EQ (__arm_set_fpm_nscale (__arm_fpm_init (), 0), 0);
> + _S_EQ (__arm_set_fpm_nscale (__arm_fpm_init (), 127), 0x7F000000);
> + _S_EQ (__arm_set_fpm_nscale (__arm_fpm_init (), -128), 0x80000000);
> +
> +#undef _S_EQ
> +}
