1 files changed, 64 insertions, 0 deletions
diff --git a/lib/builtins/fp_trunc.h b/lib/builtins/fp_trunc.h
new file mode 100644
index 000000000000..49a9aebbc67d
--- /dev/null
+++ b/lib/builtins/fp_trunc.h
@@ -0,0 +1,64 @@
+//=== lib/fp_trunc.h - high precision -> low precision conversion *- C -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Set source and destination precision setting
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef FP_TRUNC_HEADER
+#define FP_TRUNC_HEADER
+
+#include "int_lib.h"
+
+#if defined SRC_DOUBLE
+typedef double src_t;
+typedef uint64_t src_rep_t;
+#define SRC_REP_C UINT64_C
+static const int srcSigBits = 52;
+
+#elif defined SRC_QUAD
+typedef long double src_t;
+typedef __uint128_t src_rep_t;
+#define SRC_REP_C (__uint128_t)
+static const int srcSigBits = 112;
+
+#else
+#error Source should be double precision or quad precision!
+#endif //end source precision
+
+#if defined DST_DOUBLE
+typedef double dst_t;
+typedef uint64_t dst_rep_t;
+#define DST_REP_C UINT64_C
+static const int dstSigBits = 52;
+
+#elif defined DST_SINGLE
+typedef float dst_t;
+typedef uint32_t dst_rep_t;
+#define DST_REP_C UINT32_C
+static const int dstSigBits = 23;
+
+#else
+#error Destination should be single precision or double precision!
+#endif //end destination precision
+
+// End of specialization parameters.  Two helper routines for conversion to and
+// from the representation of floating-point data as integer values follow.
+
+static inline src_rep_t srcToRep(src_t x) {
+    const union { src_t f; src_rep_t i; } rep = {.f = x};
+    return rep.i;
+}
+
+static inline dst_t dstFromRep(dst_rep_t x) {
+    const union { dst_t f; dst_rep_t i; } rep = {.i = x};
+    return rep.f;
+}
+
+#endif // FP_TRUNC_HEADER