replace armhf math asm source files with inline asm

this makes it possible to inline them with LTO, and is the simplest
approach to eliminating the use of .sub files.

this also makes VFP sqrt available for use with the standard EABI
(plain arm rather than armhf subarch) when libc is built with
-mfloat-abi=softfp. the same could have been done for fabs, but when
the argument and return value are in integer registers, moving to VFP
registers and back is almost certainly more costly than a simple
integer operation.

16 files changed, 60 insertions, 40 deletions

diff --git a/src/math/arm/fabs.c b/src/math/arm/fabs.c
new file mode 100644
index 00000000..f890520a
--- /dev/null
+++ b/src/math/arm/fabs.c
@@ -0,0 +1,15 @@
+#include <math.h>
+
+#if __ARM_PCS_VFP
+
+double fabs(double x)
+{
+	__asm__ ("vabs.f64 %P0, %P1" : "=w"(x) : "w"(x));
+	return x;
+}
+
+#else
+
+#include "../fabs.c"
+
+#endif
diff --git a/src/math/arm/fabsf.c b/src/math/arm/fabsf.c
new file mode 100644
index 00000000..28153a61
--- /dev/null
+++ b/src/math/arm/fabsf.c
@@ -0,0 +1,15 @@
+#include <math.h>
+
+#if __ARM_PCS_VFP
+
+float fabsf(float x)
+{
+	__asm__ ("vabs.f32 %0, %1" : "=t"(x) : "t"(x));
+	return x;
+}
+
+#else
+
+#include "../fabsf.c"
+
+#endif
diff --git a/src/math/arm/sqrt.c b/src/math/arm/sqrt.c
new file mode 100644
index 00000000..c9c00083
--- /dev/null
+++ b/src/math/arm/sqrt.c
@@ -0,0 +1,15 @@
+#include <math.h>
+
+#if __VFP_FP__ && !__SOFTFP__
+
+double sqrt(double x)
+{
+	__asm__ ("vsqrt.f64 %P0, %P1" : "=w"(x) : "w"(x));
+	return x;
+}
+
+#else
+
+#include "../sqrt.c"
+
+#endif
diff --git a/src/math/arm/sqrtf.c b/src/math/arm/sqrtf.c
new file mode 100644
index 00000000..e6576655
--- /dev/null
+++ b/src/math/arm/sqrtf.c
@@ -0,0 +1,15 @@
+#include <math.h>
+
+#if __VFP_FP__ && !__SOFTFP__
+
+float sqrtf(float x)
+{
+	__asm__ ("vsqrt.f32 %0, %1" : "=t"(x) : "t"(x));
+	return x;
+}
+
+#else
+
+#include "../sqrtf.c"
+
+#endif
diff --git a/src/math/armebhf/fabs.sub b/src/math/armebhf/fabs.sub
deleted file mode 100644
index 10d9fb7e..00000000
--- a/src/math/armebhf/fabs.sub
+++ /dev/null
@@ -1 +0,0 @@
-../armhf/fabs.s
diff --git a/src/math/armebhf/fabsf.sub b/src/math/armebhf/fabsf.sub
deleted file mode 100644
index 940b20bd..00000000
--- a/src/math/armebhf/fabsf.sub
+++ /dev/null
@@ -1 +0,0 @@
-../armhf/fabsf.s
diff --git a/src/math/armebhf/sqrt.sub b/src/math/armebhf/sqrt.sub
deleted file mode 100644
index de2be116..00000000
--- a/src/math/armebhf/sqrt.sub
+++ /dev/null
@@ -1 +0,0 @@
-../armhf/sqrt.s
diff --git a/src/math/armebhf/sqrtf.sub b/src/math/armebhf/sqrtf.sub
deleted file mode 100644
index 150ab9cc..00000000
--- a/src/math/armebhf/sqrtf.sub
+++ /dev/null
@@ -1 +0,0 @@
-../armhf/sqrtf.s
diff --git a/src/math/armhf/fabs.s b/src/math/armhf/fabs.s
deleted file mode 100644
index 0eb458d3..00000000
--- a/src/math/armhf/fabs.s
+++ /dev/null
@@ -1,8 +0,0 @@
-.syntax unified
-.fpu vfp
-.text
-.global fabs
-.type   fabs,%function
-fabs:
-	vabs.f64 d0, d0
-	bx lr
diff --git a/src/math/armhf/fabs.sub b/src/math/armhf/fabs.sub
deleted file mode 100644
index 99e87406..00000000
--- a/src/math/armhf/fabs.sub
+++ /dev/null
@@ -1 +0,0 @@
-fabs.s
diff --git a/src/math/armhf/fabsf.s b/src/math/armhf/fabsf.s
deleted file mode 100644
index da3809bb..00000000
--- a/src/math/armhf/fabsf.s
+++ /dev/null
@@ -1,8 +0,0 @@
-.syntax unified
-.fpu vfp
-.text
-.global fabsf
-.type   fabsf,%function
-fabsf:
-	vabs.f32 s0, s0
-	bx lr
diff --git a/src/math/armhf/fabsf.sub b/src/math/armhf/fabsf.sub
deleted file mode 100644
index c04638ae..00000000
--- a/src/math/armhf/fabsf.sub
+++ /dev/null
@@ -1 +0,0 @@
-fabsf.s
diff --git a/src/math/armhf/sqrt.s b/src/math/armhf/sqrt.s
deleted file mode 100644
index e38f060d..00000000
--- a/src/math/armhf/sqrt.s
+++ /dev/null
@@ -1,8 +0,0 @@
-.syntax unified
-.fpu vfp
-.text
-.global sqrt
-.type   sqrt,%function
-sqrt:
-	vsqrt.f64 d0, d0
-	bx lr
diff --git a/src/math/armhf/sqrt.sub b/src/math/armhf/sqrt.sub
deleted file mode 100644
index 25de7cfa..00000000
--- a/src/math/armhf/sqrt.sub
+++ /dev/null
@@ -1 +0,0 @@
-sqrt.s
diff --git a/src/math/armhf/sqrtf.s b/src/math/armhf/sqrtf.s
deleted file mode 100644
index 38c7ee89..00000000
--- a/src/math/armhf/sqrtf.s
+++ /dev/null
@@ -1,8 +0,0 @@
-.syntax unified
-.fpu vfp
-.text
-.global sqrtf
-.type   sqrtf,%function
-sqrtf:
-	vsqrt.f32 s0, s0
-	bx lr
diff --git a/src/math/armhf/sqrtf.sub b/src/math/armhf/sqrtf.sub
deleted file mode 100644
index 3bcbac87..00000000
--- a/src/math/armhf/sqrtf.sub
+++ /dev/null
@@ -1 +0,0 @@
-sqrtf.s