From 4abab5ad6c8465a7528ccdd5f49367da05f78bbd Mon Sep 17 00:00:00 2001
From: Vladimir Azarov <avm@intermediate-node.net>
Date: Tue, 1 Oct 2024 15:47:05 +0200
Subject: Initial version

---
 src/math/x86_64/fabs.c | 10 ++++++++++
 1 file changed, 10 insertions(+)
 create mode 100644 src/math/x86_64/fabs.c

(limited to 'src/math/x86_64/fabs.c')

diff --git a/src/math/x86_64/fabs.c b/src/math/x86_64/fabs.c
new file mode 100644
index 0000000..1656247
--- /dev/null
+++ b/src/math/x86_64/fabs.c
@@ -0,0 +1,10 @@
+#include <math.h>
+
+double fabs(double x)
+{
+	double t;
+	__asm__ ("pcmpeqd %0, %0" : "=x"(t));          // t = ~0
+	__asm__ ("psrlq   $1, %0" : "+x"(t));          // t >>= 1
+	__asm__ ("andps   %1, %0" : "+x"(x) : "x"(t)); // x &= t
+	return x;
+}
-- 
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