Hi Karl,
I think the component tags in the subject line, AArch64, in this
example, should be lowercase so maybe use it like "aarch64:". Its not
something documented but just something I have seen in other places.
It would also be helpful to have a short summary in the body of the
email which will be included in the commit message. Something along the
lines of "Add support for +sme-lutv2 which enables support for the SME
LUTv2 instructions".
You also need to add to the new flag at `gcc/doc/invoke.texi` file.
More comments inline.
On 9/2/2025 3:16 PM, Karl Meakin wrote:
gcc/ChangeLog:
* config/aarch64/aarch64-c.cc (aarch64_update_cpp_builtins):
Conditonally define
`__ARM_FEATURE_SME_LUTv2" macro.
* config/aarch64/aarch64-option-extensions.def
(AARCH64_OPT_EXTENSION("sme-lutv2")): New
optional architecture extension.
* config/aarch64/aarch64.h (TARGET_SME_LUTv2): New macro.
---
gcc/config/aarch64/aarch64-c.cc | 1 +
gcc/config/aarch64/aarch64-option-extensions.def | 2 ++
gcc/config/aarch64/aarch64.h | 7 ++++++-
3 files changed, 9 insertions(+), 1 deletion(-)
diff --git a/gcc/config/aarch64/aarch64-c.cc b/gcc/config/aarch64/aarch64-c.cc
index 98337b7f693..a8ff58e4994 100644
--- a/gcc/config/aarch64/aarch64-c.cc
+++ b/gcc/config/aarch64/aarch64-c.cc
@@ -269,6 +269,7 @@ aarch64_update_cpp_builtins (cpp_reader *pfile)
"__ARM_FEATURE_SVE_BF16", pfile);
aarch64_def_or_undef (TARGET_LUT, "__ARM_FEATURE_LUT", pfile);
+ aarch64_def_or_undef (TARGET_SME_LUTv2, "__ARM_FEATURE_SME_LUTv2", pfile);
aarch64_def_or_undef (TARGET_FP8, "__ARM_FEATURE_FP8", pfile);
diff --git a/gcc/config/aarch64/aarch64-option-extensions.def b/gcc/config/aarch64/aarch64-option-extensions.def
index db88df08a6a..a70375c053f 100644
--- a/gcc/config/aarch64/aarch64-option-extensions.def
+++ b/gcc/config/aarch64/aarch64-option-extensions.def
@@ -277,6 +277,8 @@ AARCH64_OPT_EXTENSION("ssve-fp8dot2", SSVE_FP8DOT2, (SME2, FP8),
(), (), "smesf8
AARCH64_OPT_EXTENSION("lut", LUT, (SIMD), (), (), "lut")
+AARCH64_OPT_EXTENSION ("sme-lutv2", SME_LUTv2, (SME2), (), (), "sme-lutv2")
+
AARCH64_OPT_EXTENSION("cpa", CPA, (), (), (), "")
#undef AARCH64_OPT_FMV_EXTENSION
diff --git a/gcc/config/aarch64/aarch64.h b/gcc/config/aarch64/aarch64.h
index 2b3610c86ed..899abb8e9df 100644
--- a/gcc/config/aarch64/aarch64.h
+++ b/gcc/config/aarch64/aarch64.h
@@ -477,9 +477,14 @@ constexpr auto AARCH64_FL_DEFAULT_ISA_MODE ATTRIBUTE_UNUSED
enabled through +faminmax. */
#define TARGET_FAMINMAX AARCH64_HAVE_ISA (FAMINMAX)
-/* Lookup table (LUTI) extension instructions are enabled through +lut. */
+/* Lookup table (LUTI) extension instructions with 2-bit indices and 2-bit
+ indices are enabled through +lut. */
Should this be "2-bit indices and 4-bit indices"? Or even "2-bit and
4-bit indices"?> #define TARGET_LUT AARCH64_HAVE_ISA (LUT)
+/* Lookup table (LUTI) extension instructions with 4-bit indices and 8-bit
+ elements are enabled through +sme-lutv2. */
How about "4-bit and 8-bit indices?" Unless I am misunderstanding
something and 8-bit elements are actually a thing.> +#define
TARGET_SME_LUTv2 AARCH64_HAVE_ISA (SME_LUTv2)
+
/* Prefer different predicate registers for the output of a predicated
operation over re-using an existing input predicate. */
#define TARGET_SVE_PRED_CLOBBER (TARGET_SVE \
Thanks,
Saurabh
