[PATCH] mips: add single-instruction math functions

[<info@mobile-stream.com>]

non-commit text:
gcc puts annoying nop into the delay slot for these functions, e.g.:
	abs.d	$f0,$f12
	jr	$ra
	 nop
is there any way to get rid of this without using pure .S?



SQRT.fmt exists on MIPS II+ (float), MIPS III+ (double).

ABS.fmt exists on MIPS I+ but only cores with ABS2008 flag in FCSR
implement the required behaviour.
---
 src/math/mips/fabs.c  | 16 ++++++++++++++++
 src/math/mips/fabsf.c | 16 ++++++++++++++++
 src/math/mips/sqrt.c  | 16 ++++++++++++++++
 src/math/mips/sqrtf.c | 16 ++++++++++++++++
 4 files changed, 64 insertions(+)
 create mode 100644 src/math/mips/fabs.c
 create mode 100644 src/math/mips/fabsf.c
 create mode 100644 src/math/mips/sqrt.c
 create mode 100644 src/math/mips/sqrtf.c

diff --git a/src/math/mips/fabs.c b/src/math/mips/fabs.c
new file mode 100644
index 00000000..0a5aa3b1
--- /dev/null
+++ b/src/math/mips/fabs.c
@@ -0,0 +1,16 @@
+#if !defined(__mips_soft_float) && defined(__mips_abs2008)
+
+#include <math.h>
+
+double fabs(double x)
+{
+	double r;
+	__asm__("abs.d %0,%1" : "=f"(r) : "f"(x));
+	return r;
+}
+
+#else
+
+#include "../fabs.c"
+
+#endif
diff --git a/src/math/mips/fabsf.c b/src/math/mips/fabsf.c
new file mode 100644
index 00000000..35307be6
--- /dev/null
+++ b/src/math/mips/fabsf.c
@@ -0,0 +1,16 @@
+#if !defined(__mips_soft_float) && defined(__mips_abs2008)
+
+#include <math.h>
+
+float fabsf(float x)
+{
+	float r;
+	__asm__("abs.s %0,%1" : "=f"(r) : "f"(x));
+	return r;
+}
+
+#else
+
+#include "../fabsf.c"
+
+#endif
diff --git a/src/math/mips/sqrt.c b/src/math/mips/sqrt.c
new file mode 100644
index 00000000..595c9dbc
--- /dev/null
+++ b/src/math/mips/sqrt.c
@@ -0,0 +1,16 @@
+#if !defined(__mips_soft_float) && __mips >= 3
+
+#include <math.h>
+
+double sqrt(double x)
+{
+	double r;
+	__asm__("sqrt.d %0,%1" : "=f"(r) : "f"(x));
+	return r;
+}
+
+#else
+
+#include "../sqrt.c"
+
+#endif
diff --git a/src/math/mips/sqrtf.c b/src/math/mips/sqrtf.c
new file mode 100644
index 00000000..84090d2d
--- /dev/null
+++ b/src/math/mips/sqrtf.c
@@ -0,0 +1,16 @@
+#if !defined(__mips_soft_float) && __mips >= 2
+
+#include <math.h>
+
+float sqrtf(float x)
+{
+	float r;
+	__asm__("sqrt.s %0,%1" : "=f"(r) : "f"(x));
+	return r;
+}
+
+#else
+
+#include "../sqrtf.c"
+
+#endif
-- 
2.23.0.windows.1