Imported Upstream version 60upstream/60

1 files changed, 26 insertions, 0 deletions

diff --git a/src/pkg/math/tan_386.s b/src/pkg/math/tan_386.s
new file mode 100644
index 000000000..ebb9e798b
--- /dev/null
+++ b/src/pkg/math/tan_386.s
@@ -0,0 +1,26 @@
+// Copyright 2010 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// func Tan(x float64) float64
+TEXT ·Tan(SB),7,$0
+	FMOVD   x+0(FP), F0  // F0=x
+	FPTAN                // F0=1, F1=tan(x) if -2**63 < x < 2**63
+	FSTSW   AX           // AX=status word
+	ANDW    $0x0400, AX
+	JNE     4(PC)        // jump if x outside range
+	FMOVDP  F0, F0       // F0=tan(x)
+	FMOVDP  F0, r+8(FP)
+	RET
+	FLDPI                // F0=Pi, F1=x
+	FADDD   F0, F0       // F0=2*Pi, F1=x
+	FXCHD   F0, F1       // F0=x, F1=2*Pi
+	FPREM1               // F0=reduced_x, F1=2*Pi
+	FSTSW   AX           // AX=status word
+	ANDW    $0x0400, AX
+	JNE     -3(PC)       // jump if reduction incomplete
+	FMOVDP  F0, F1       // F0=reduced_x
+	FPTAN                // F0=1, F1=tan(reduced_x)
+	FMOVDP  F0, F0       // F0=tan(reduced_x)
+	FMOVDP  F0, r+8(FP)
+	RET