Add hard float versions of FP to LL conversions

This adds hard-float implementation for the following builtins:

* __fixdfdi()
* __fixsfdi()
* __fixunsdfdi()
* __fixunssfdi()

The soft-float implementation does never raise floating point
exceptions, which doesn't allow clients to detect floating point
conversion errors.

I must mention that I had to refer to libgcc's implementation to
write these functions.

Related unit-tests of compiler-rt passed with these changes.

Patch was somewhat out-dated, so was updated locally without any
functional changes.

Differential Revision: http://reviews.llvm.org/D5376

llvm-svn: 234148

1 files changed, 24 insertions, 2 deletions

diff --git a/compiler-rt/lib/builtins/fixunsdfdi.c b/compiler-rt/lib/builtins/fixunsdfdi.c
index f4f689e3993..b93d1c10bff 100644
--- a/compiler-rt/lib/builtins/fixunsdfdi.c
+++ b/compiler-rt/lib/builtins/fixunsdfdi.c
@@ -10,12 +10,34 @@
 
 #define DOUBLE_PRECISION
 #include "fp_lib.h"
-typedef du_int fixuint_t;
-#include "fp_fixuint_impl.inc"
 
 ARM_EABI_FNALIAS(d2ulz, fixunsdfdi)
 
+#ifndef __SOFT_FP__
+/* Support for systems that have hardware floating-point; can set the invalid
+ * flag as a side-effect of computation.
+ */
+
+COMPILER_RT_ABI du_int
+__fixunsdfdi(double a)
+{
+    su_int high = a/0x1p32f;
+    su_int low = a - (double)high*0x1p32f;
+    return ((du_int)high << 32) | low;
+}
+
+#else
+/* Support for systems that don't have hardware floating-point; there are no
+ * flags to set, and we don't want to code-gen to an unknown soft-float
+ * implementation.
+ */
+
+typedef du_int fixuint_t;
+#include "fp_fixuint_impl.inc"
+
 COMPILER_RT_ABI du_int
 __fixunsdfdi(fp_t a) {
     return __fixuint(a);
 }
+
+#endif