Refactor float to integer conversion to share the same code.

80bit Intel/PPC long double is excluded due to lacking support
for the abstraction. Consistently provide saturation logic.
Extend to long double on 128bit IEEE extended platforms.

Initial patch with test cases from GuanHong Liu.
Reviewed by Steve Canon.

Differential Revision: http://reviews.llvm.org/D2804

llvm-svn: 231965

1 files changed, 7 insertions, 26 deletions

diff --git a/compiler-rt/lib/builtins/fixsfti.c b/compiler-rt/lib/builtins/fixsfti.c
index 6a1a1c6d546..3a159b3e18e 100644
--- a/compiler-rt/lib/builtins/fixsfti.c
+++ b/compiler-rt/lib/builtins/fixsfti.c
@@ -6,40 +6,21 @@
  * Source Licenses. See LICENSE.TXT for details.
  *
  * ===----------------------------------------------------------------------===
- *
- * This file implements __fixsfti for the compiler_rt library.
- *
- * ===----------------------------------------------------------------------===
  */
 
 #include "int_lib.h"
 
 #ifdef CRT_HAS_128BIT
+#define SINGLE_PRECISION
+#include "fp_lib.h"
 
-/* Returns: convert a to a signed long long, rounding toward zero. */
-
-/* Assumption: float is a IEEE 32 bit floating point type 
- *             su_int is a 32 bit integral type
- *             value in float is representable in ti_int (no range checking performed)
- */
-
-/* seee eeee emmm mmmm mmmm mmmm mmmm mmmm */
+typedef ti_int fixint_t;
+typedef tu_int fixuint_t;
+#include "fp_fixint_impl.inc"
 
 COMPILER_RT_ABI ti_int
-__fixsfti(float a)
-{
-    float_bits fb;
-    fb.f = a;
-    int e = ((fb.u & 0x7F800000) >> 23) - 127;
-    if (e < 0)
-        return 0;
-    ti_int s = (si_int)(fb.u & 0x80000000) >> 31;
-    ti_int r = (fb.u & 0x007FFFFF) | 0x00800000;
-    if (e > 23)
-        r <<= (e - 23);
-    else
-        r >>= (23 - e);
-    return (r ^ s) - s;
+__fixsfti(fp_t a) {
+    return __fixint(a);
 }
 
 #endif /* CRT_HAS_128BIT */