Provide add and sub for IEEE quad. From GuanHong Liu.

Differential Revision: http://reviews.llvm.org/D2798

llvm-svn: 211312
diff --git a/compiler-rt/lib/builtins/CMakeLists.txt b/compiler-rt/lib/builtins/CMakeLists.txt
index f2cdb04..7e279f2 100644
--- a/compiler-rt/lib/builtins/CMakeLists.txt
+++ b/compiler-rt/lib/builtins/CMakeLists.txt
@@ -8,6 +8,7 @@
   absvti2.c
   adddf3.c
   addsf3.c
+  addtf3.c
   addvdi3.c
   addvsi3.c
   addvti3.c
@@ -38,6 +39,7 @@
   divsf3.c
   divsi3.c
   divti3.c
+  divtf3.c
   divxc3.c
   enable_execute_stack.c
   eprintf.c
@@ -119,6 +121,7 @@
   subvdi3.c
   subvsi3.c
   subvti3.c
+  subtf3.c
   trampoline_setup.c
   truncdfsf2.c
   ucmpdi2.c
diff --git a/compiler-rt/lib/builtins/addtf3.c b/compiler-rt/lib/builtins/addtf3.c
new file mode 100644
index 0000000..e4bbe02
--- /dev/null
+++ b/compiler-rt/lib/builtins/addtf3.c
@@ -0,0 +1,25 @@
+//===-- lib/addtf3.c - Quad-precision addition --------------------*- 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.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements quad-precision soft-float addition with the IEEE-754
+// default rounding (to nearest, ties to even).
+//
+//===----------------------------------------------------------------------===//
+
+#define QUAD_PRECISION
+#include "fp_lib.h"
+
+#if defined(CRT_HAS_128BIT) && defined(CRT_LDBL_128BIT)
+#include "fp_add_impl.inc"
+
+COMPILER_RT_ABI long double __addtf3(long double a, long double b){
+    return __addXf3__(a, b);
+}
+
+#endif
diff --git a/compiler-rt/lib/builtins/subtf3.c b/compiler-rt/lib/builtins/subtf3.c
new file mode 100644
index 0000000..609b816
--- /dev/null
+++ b/compiler-rt/lib/builtins/subtf3.c
@@ -0,0 +1,27 @@
+//===-- lib/subtf3.c - Quad-precision subtraction -----------------*- 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.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements quad-precision soft-float subtraction with the
+// IEEE-754 default rounding (to nearest, ties to even).
+//
+//===----------------------------------------------------------------------===//
+
+#define QUAD_PRECISION
+#include "fp_lib.h"
+
+#if defined(CRT_HAS_128BIT) && defined(CRT_LDBL_128BIT)
+COMPILER_RT_ABI fp_t __addtf3(fp_t a, fp_t b);
+
+// Subtraction; flip the sign bit of b and add.
+COMPILER_RT_ABI fp_t
+__subtf3(fp_t a, fp_t b) {
+    return __addtf3(a, fromRep(toRep(b) ^ signBit));
+}
+
+#endif