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

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@234148 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 97 insertions, 4 deletions

diff --git a/lib/builtins/fixdfdi.c b/lib/builtins/fixdfdi.c
index 67b124a16..14283ef42 100644
--- a/lib/builtins/fixdfdi.c
+++ b/lib/builtins/fixdfdi.c
@@ -12,6 +12,28 @@
 #include "fp_lib.h"
 ARM_EABI_FNALIAS(d2lz, fixdfdi)
 
+#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);
+
+COMPILER_RT_ABI di_int
+__fixdfdi(double a)
+{
+    if (a < 0.0) {
+        return -__fixunsdfdi(-a);
+    }
+    return __fixunsdfdi(a);
+}
+
+#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 di_int fixint_t;
 typedef du_int fixuint_t;
 #include "fp_fixint_impl.inc"
@@ -20,3 +42,5 @@ COMPILER_RT_ABI di_int
 __fixdfdi(fp_t a) {
     return __fixint(a);
 }
+
+#endif
diff --git a/lib/builtins/fixsfdi.c b/lib/builtins/fixsfdi.c
index 835ff852d..fab47e272 100644
--- a/lib/builtins/fixsfdi.c
+++ b/lib/builtins/fixsfdi.c
@@ -13,6 +13,28 @@
 
 ARM_EABI_FNALIAS(f2lz, fixsfdi)
 
+#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 __fixunssfdi(float a);
+
+COMPILER_RT_ABI di_int
+__fixsfdi(float a)
+{
+    if (a < 0.0f) {
+        return -__fixunssfdi(-a);
+    }
+    return __fixunssfdi(a);
+}
+
+#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 di_int fixint_t;
 typedef du_int fixuint_t;
 #include "fp_fixint_impl.inc"
@@ -21,3 +43,5 @@ COMPILER_RT_ABI di_int
 __fixsfdi(fp_t a) {
     return __fixint(a);
 }
+
+#endif
diff --git a/lib/builtins/fixunsdfdi.c b/lib/builtins/fixunsdfdi.c
index f4f689e39..b93d1c10b 100644
--- a/lib/builtins/fixunsdfdi.c
+++ b/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
diff --git a/lib/builtins/fixunssfdi.c b/lib/builtins/fixunssfdi.c
index cd21cfd18..374ebbe82 100644
--- a/lib/builtins/fixunssfdi.c
+++ b/lib/builtins/fixunssfdi.c
@@ -10,12 +10,35 @@
 
 #define SINGLE_PRECISION
 #include "fp_lib.h"
-typedef du_int fixuint_t;
-#include "fp_fixuint_impl.inc"
 
 ARM_EABI_FNALIAS(f2ulz, fixunssfdi)
 
+#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
+__fixunssfdi(float a)
+{
+    double da = a;
+    su_int high = da/0x1p32f;
+    su_int low = da - (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
 __fixunssfdi(fp_t a) {
     return __fixuint(a);
 }
+
+#endif