lib/libm: Move Thumb-specific sqrtf function to separate file.

This allows it to be used only when the hardware supports VFP
instructions, preventing compile errors.

2 files changed, 11 insertions, 13 deletions

diff --git a/lib/libm/math.c b/lib/libm/math.c
index 7cbec5fb32..732049236d 100644
--- a/lib/libm/math.c
+++ b/lib/libm/math.c
@@ -86,19 +86,6 @@ double __aeabi_dmul(double x , double y) {
 
 #endif // defined(__thumb__)
 
-// TODO this needs a better way of testing for Thumb2 FP hardware
-#if defined(__thumb2__)
-
-float sqrtf(float x) {
-    asm volatile (
-            "vsqrt.f32  %[r], %[x]\n"
-            : [r] "=t" (x)
-            : [x] "t"  (x));
-    return x;
-}
-
-#endif
-
 #ifndef NDEBUG
 float copysignf(float x, float y) {
     float_s_t fx={.f = x};
diff --git a/lib/libm/thumb_vfp_sqrtf.c b/lib/libm/thumb_vfp_sqrtf.c
new file mode 100644
index 0000000000..12ffebf827
--- /dev/null
+++ b/lib/libm/thumb_vfp_sqrtf.c
@@ -0,0 +1,11 @@
+// an implementation of sqrtf for Thumb using hardware VFP instructions
+
+#include <math.h>
+
+float sqrtf(float x) {
+    asm volatile (
+            "vsqrt.f32  %[r], %[x]\n"
+            : [r] "=t" (x)
+            : [x] "t"  (x));
+    return x;
+}