[PATCH] [COMPILER_RT] Implement __extendsftf2, __extenddftf2

[Dmitri Gribenko]

  Please note the other comment by Joerg that it is more idiomatic to change these header files to .inc files that would be used like:

  #define NAME runtimefuncf
  #include "runtimefunc_impl.inc"

  This avoids ugly '\' markers in the implementation, and brings back source highlighting in editors.


================
Comment at: test/builtins/Unit/extenddftf2_test.c:24-25
@@ +23,4 @@
+{
+    long double x = __extenddftf2(a);
+    long double expected = (long double)a;
+    if (x != expected)
----------------
This is not testing much...  If (long double) conversion is implemented as a call to the runtime library, this could be just calling back to the installed version of compiler-rt.


http://llvm-reviews.chandlerc.com/D2802