From: Kyrylo Tkachov <ktkachov@nvidia.com>
Date: Thu, 27 Jun 2024 10:40:41 +0000 (+0530)
Subject: aarch64: PR target/115457 Implement missing __ARM_FEATURE_BF16 macro
X-Git-Tag: releases/gcc-11.5.0~20
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d32cfe3352f3863325f8452e83400063b1e71e5b;p=thirdparty%2Fgcc.git

aarch64: PR target/115457 Implement missing __ARM_FEATURE_BF16 macro

The ACLE asks the user to test for __ARM_FEATURE_BF16 before using the
<arm_bf16.h> header but GCC doesn't set this up.
LLVM does, so this is an inconsistency between the compilers.

This patch enables that macro for TARGET_BF16_FP.
Bootstrapped and tested on aarch64-none-linux-gnu.

gcc/

	PR target/115457
	* config/aarch64/aarch64-c.c (aarch64_update_cpp_builtins):
	Define __ARM_FEATURE_BF16 for TARGET_BF16_FP.

gcc/testsuite/

	PR target/115457
	* gcc.target/aarch64/acle/bf16_feature.c: New test.

Signed-off-by: Kyrylo Tkachov <ktkachov@nvidia.com>
(cherry picked from commit c10942134fa759843ac1ed1424b86fcb8e6368ba)
---

diff --git a/gcc/config/aarch64/aarch64-c.c b/gcc/config/aarch64/aarch64-c.c
index 05869463e4ba..f6d90affd374 100644
--- a/gcc/config/aarch64/aarch64-c.c
+++ b/gcc/config/aarch64/aarch64-c.c
@@ -200,6 +200,8 @@ aarch64_update_cpp_builtins (cpp_reader *pfile)
 			"__ARM_FEATURE_BF16_VECTOR_ARITHMETIC", pfile);
   aarch64_def_or_undef (TARGET_BF16_FP,
 			"__ARM_FEATURE_BF16_SCALAR_ARITHMETIC", pfile);
+  aarch64_def_or_undef (TARGET_BF16_FP,
+			"__ARM_FEATURE_BF16", pfile);
   aarch64_def_or_undef (AARCH64_ISA_RCPC, "__ARM_FEATURE_RCPC", pfile);
 
   /* Not for ACLE, but required to keep "float.h" correct if we switch
diff --git a/gcc/testsuite/gcc.target/aarch64/acle/bf16_feature.c b/gcc/testsuite/gcc.target/aarch64/acle/bf16_feature.c
new file mode 100644
index 000000000000..96584b4b9887
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/acle/bf16_feature.c
@@ -0,0 +1,10 @@
+/* { dg-do compile } */
+
+#pragma GCC target "+bf16"
+#ifndef __ARM_FEATURE_BF16
+#error "__ARM_FEATURE_BF16 is not defined but should be!"
+#endif
+
+void
+foo (void) {}
+