math.nbtheory: Implement natural logarithm

1 files changed, 48 insertions, 0 deletions

diff --git a/arch/x64/linux/math/log.S b/arch/x64/linux/math/log.S
new file mode 100644
index 0000000..7f23703
--- /dev/null
+++ b/arch/x64/linux/math/log.S
@@ -0,0 +1,48 @@
+	.text
+
+
+// logl.
+	.globl _D5tanya4math8nbtheory2lnFNaNbNiNfeZe
+	.type _D5tanya4math8nbtheory2lnFNaNbNiNfeZe, @function
+
+_D5tanya4math8nbtheory2lnFNaNbNiNfeZe:
+	fldln2 // Put lb(e) onto the FPU stack
+	fldt 8(%rsp) // Put the argument onto the FPU stack
+	fyl2x // %st1 * lb(%st0)
+	ret
+
+
+// log.
+	.globl _D5tanya4math8nbtheory2lnFNaNbNiNfdZd
+	.type _D5tanya4math8nbtheory2lnFNaNbNiNfdZd, @function
+
+_D5tanya4math8nbtheory2lnFNaNbNiNfdZd:
+	movsd %xmm0, -8(%rsp) // Put the argument onto the stack
+
+	fldln2 // Put lb(e) onto the FPU stack
+	fldl -8(%rsp) // Put a double onto the FPU stack
+	fyl2x // %st1 * lb(%st0)
+
+	 // The result is on the FPU stack, but returned in %xmm0
+	fstpl -8(%rsp)
+	movsd -8(%rsp), %xmm0
+
+	ret
+
+
+// logf.
+	.globl _D5tanya4math8nbtheory2lnFNaNbNiNffZf
+	.type _D5tanya4math8nbtheory2lnFNaNbNiNffZf, @function
+
+_D5tanya4math8nbtheory2lnFNaNbNiNffZf:
+	movss %xmm0, -4(%rsp) // Put the argument onto the stack
+
+	fldln2 // Put lb(e) onto the FPU stack
+	flds -4(%rsp) // Put a float onto the FPU stack
+	fyl2x // %st1 * lb(%st0)
+
+	 // The result is on the FPU stack, but returned in %xmm0
+	fstps -4(%rsp)
+	movss -4(%rsp), %xmm0
+
+	ret