[PATCH] x86-64: Add x87 fmod and remainder [BZ #30179]

[H.J. Lu]

X87 (fprem/fprem1) implementations of fmod and remainder are much faster
than generic fmod and remainder.  Add e_fmod.S, e_fmodf.S, e_remainder.S
and e_remainderf.S with fprem/fprem1.  This fixes BZ #30179.
---
 sysdeps/x86_64/fpu/e_fmod.S       | 22 ++++++++++++++++++++++
 sysdeps/x86_64/fpu/e_fmodf.S      | 22 ++++++++++++++++++++++
 sysdeps/x86_64/fpu/e_remainder.S  | 22 ++++++++++++++++++++++
 sysdeps/x86_64/fpu/e_remainderf.S | 22 ++++++++++++++++++++++
 4 files changed, 88 insertions(+)
 create mode 100644 sysdeps/x86_64/fpu/e_fmod.S
 create mode 100644 sysdeps/x86_64/fpu/e_fmodf.S
 create mode 100644 sysdeps/x86_64/fpu/e_remainder.S
 create mode 100644 sysdeps/x86_64/fpu/e_remainderf.S

diff --git a/sysdeps/x86_64/fpu/e_fmod.S b/sysdeps/x86_64/fpu/e_fmod.S
new file mode 100644
index 0000000000..4bdc8a1ab0
--- /dev/null
+++ b/sysdeps/x86_64/fpu/e_fmod.S
@@ -0,0 +1,22 @@
+/*
+ * Public domain.
+ */
+
+#include <machine/asm.h>
+#include <libm-alias-finite.h>
+
+ENTRY(__ieee754_fmod)
+	movsd	%xmm0, -16(%rsp)
+	movsd	%xmm1, -8(%rsp)
+	fldl	-8(%rsp)
+	fldl	-16(%rsp)
+1:	fprem
+	fstsw	%ax
+	sahf
+	jp	1b
+	fstp	%st(1)
+	fstpl	-8(%rsp)
+	movsd	-8(%rsp), %xmm0
+	ret
+END (__ieee754_fmod)
+libm_alias_finite (__ieee754_fmod, __fmod)
diff --git a/sysdeps/x86_64/fpu/e_fmodf.S b/sysdeps/x86_64/fpu/e_fmodf.S
new file mode 100644
index 0000000000..6f76daff01
--- /dev/null
+++ b/sysdeps/x86_64/fpu/e_fmodf.S
@@ -0,0 +1,22 @@
+/*
+ * Public domain.
+ */
+
+#include <machine/asm.h>
+#include <libm-alias-finite.h>
+
+ENTRY(__ieee754_fmodf)
+	movss	%xmm0, -8(%rsp)
+	movss	%xmm1, -4(%rsp)
+	flds	-4(%rsp)
+	flds	-8(%rsp)
+1:	fprem
+	fstsw	%ax
+	sahf
+	jp	1b
+	fstp	%st(1)
+	fstps	-4(%rsp)
+	movss	-4(%rsp), %xmm0
+	ret
+END (__ieee754_fmodf)
+libm_alias_finite (__ieee754_fmodf, __fmodf)
diff --git a/sysdeps/x86_64/fpu/e_remainder.S b/sysdeps/x86_64/fpu/e_remainder.S
new file mode 100644
index 0000000000..be2184f25a
--- /dev/null
+++ b/sysdeps/x86_64/fpu/e_remainder.S
@@ -0,0 +1,22 @@
+/*
+ * Public domain.
+ */
+
+#include <machine/asm.h>
+#include <libm-alias-finite.h>
+
+ENTRY(__ieee754_remainder)
+	movsd	%xmm0, -16(%rsp)
+	movsd	%xmm1, -8(%rsp)
+	fldl	-8(%rsp)
+	fldl	-16(%rsp)
+1:	fprem1
+	fstsw	%ax
+	sahf
+	jp	1b
+	fstp	%st(1)
+	fstpl	-8(%rsp)
+	movsd	-8(%rsp), %xmm0
+	ret
+END (__ieee754_remainder)
+libm_alias_finite (__ieee754_remainder, __remainder)
diff --git a/sysdeps/x86_64/fpu/e_remainderf.S b/sysdeps/x86_64/fpu/e_remainderf.S
new file mode 100644
index 0000000000..42972d3f84
--- /dev/null
+++ b/sysdeps/x86_64/fpu/e_remainderf.S
@@ -0,0 +1,22 @@
+/*
+ * Public domain.
+ */
+
+#include <machine/asm.h>
+#include <libm-alias-finite.h>
+
+ENTRY(__ieee754_remainderf)
+	movss	%xmm0, -8(%rsp)
+	movss	%xmm1, -4(%rsp)
+	flds	-4(%rsp)
+	flds	-8(%rsp)
+1:	fprem1
+	fstsw	%ax
+	sahf
+	jp	1b
+	fstp	%st(1)
+	fstps	-4(%rsp)
+	movss	-4(%rsp), %xmm0
+	ret
+END (__ieee754_remainderf)
+libm_alias_finite (__ieee754_remainderf, __remainderf)
-- 
2.39.2