From: Rich Felker <dalias@aerifal.cx>
Date: Tue, 20 Mar 2012 03:08:49 +0000 (-0400)
Subject: use alternate formula for acos asm to avoid loss of precision
X-Git-Url: http://nsz.repo.hu/git/?p=musl;a=commitdiff_plain;h=804fbf0b8c00fd4e2f37ef0769a610614d06138f

use alternate formula for acos asm to avoid loss of precision
---

diff --git a/src/math/i386/acos.s b/src/math/i386/acos.s
index 6f9ef7f0..4f0168f6 100644
--- a/src/math/i386/acos.s
+++ b/src/math/i386/acos.s
@@ -14,11 +14,19 @@ acosl:
 .type acos,@function
 acos:
 	fldl 4(%esp)
-1:	fld %st(0)
-	fmul %st(0)
+1:	fld1
+	fld %st(1)
 	fld1
-	fsubp %st(1)
+	fsubp
+	fxch %st(2)
+	faddp
+	fdivp
 	fsqrt
+	fld1
 	fxch %st(1)
 	fpatan
+	fld1
+	fld1
+	faddp
+	fmulp
 	ret