From f4f7216c56fe2f67c72db5b7c4afa220725f3ed1 Mon Sep 17 00:00:00 2001
From: Ayan Shafqat <ayan.x.shafqat@gmail.com>
Date: Mon, 17 Mar 2025 09:28:27 +0100
Subject: [PATCH] Aarch64: Add FMA and FMAF intrinsic and corresponding tests

This patch introduces inline definitions for the __fma and __fmaf
functions in arm_acle.h for Aarch64 targets. These definitions rely on
__builtin_fma and __builtin_fmaf to ensure proper inlining and to meet
the ACLE requirements [1].

The patch has been tested locally using a crosstool-NG sysroot for
Aarch64, confirming that the generated code uses the expected fused
multiply-accumulate instructions (fmadd).

[1] https://arm-software.github.io/acle/main/acle.html#fused-multiply-accumulate-fma

gcc/ChangeLog:

	* config/aarch64/arm_acle.h (__fma, __fmaf): New functions.

gcc/testsuite/ChangeLog:

	* gcc.target/aarch64/acle/acle_fma.c: New test.
---
 gcc/config/aarch64/arm_acle.h                   | 14 ++++++++++++++
 .../gcc.target/aarch64/acle/acle_fma.c          | 17 +++++++++++++++++
 2 files changed, 31 insertions(+)
 create mode 100644 gcc/testsuite/gcc.target/aarch64/acle/acle_fma.c

diff --git a/gcc/config/aarch64/arm_acle.h b/gcc/config/aarch64/arm_acle.h
index 7976c117daf..d9e2401ea9f 100644
--- a/gcc/config/aarch64/arm_acle.h
+++ b/gcc/config/aarch64/arm_acle.h
@@ -129,6 +129,20 @@ __jcvt (double __a)
 
 #pragma GCC pop_options
 
+__extension__ extern __inline double
+__attribute__ ((__always_inline__, __gnu_inline__, __artificial__))
+__fma (double __x, double __y, double __z)
+{
+  return __builtin_fma (__x, __y, __z);
+}
+
+__extension__ extern __inline float
+__attribute__ ((__always_inline__, __gnu_inline__, __artificial__))
+__fmaf (float __x, float __y, float __z)
+{
+  return __builtin_fmaf (__x, __y, __z);
+}
+
 #pragma GCC push_options
 #pragma GCC target ("+nothing+frintts")
 __extension__ extern __inline float
diff --git a/gcc/testsuite/gcc.target/aarch64/acle/acle_fma.c b/gcc/testsuite/gcc.target/aarch64/acle/acle_fma.c
new file mode 100644
index 00000000000..9363a75b593
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/acle/acle_fma.c
@@ -0,0 +1,17 @@
+/* { dg-do compile } */
+/* { dg-options "-O2" } */
+
+#include "arm_acle.h"
+
+double test_acle_fma (double x, double y, double z)
+{
+  return __fma (x, y, z);
+}
+
+float test_acle_fmaf (float x, float y, float z)
+{
+  return __fmaf (x, y, z);
+}
+
+/* { dg-final { scan-assembler-times "fmadd\td\[0-9\]" 1 } } */
+/* { dg-final { scan-assembler-times "fmadd\ts\[0-9\]" 1 } } */