Support IRgen of sqrt -> llvm.sqrt, pow -> llvm.pow.

 - Define pow[lf]?, sqrt[lf]? as builtins.

 - Add -fmath-errno option which binds to LangOptions.MathErrno

 - Add new builtin flag Builtin::Context::isConstWithoutErrno for
   functions which can be marked as const if errno isn't respected for
   math functions. Sema automatically marks these functions as const
   when they are defined, if MathErrno=0.

 - IRgen uses const attribute on sqrt and pow library functions to
   decide if it can use the llvm intrinsic.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@64689 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 4 insertions, 0 deletions

diff --git a/include/clang/Basic/LangOptions.h b/include/clang/Basic/LangOptions.h
index 12fffb332d..0124b04aa9 100644
--- a/include/clang/Basic/LangOptions.h
+++ b/include/clang/Basic/LangOptions.h
@@ -54,6 +54,9 @@ public:
   unsigned Blocks            : 1; // block extension to C
   unsigned EmitAllDecls      : 1; // Emit all declarations, even if
                                   // they are unused.
+  unsigned MathErrno         : 1; // Math functions must respect errno
+                                  // (modulo the platform support).
+
 private:
   unsigned GC : 2; // Objective-C Garbage Collection modes.  We declare
                    // this enum as unsigned because MSVC insists on making enums
@@ -76,6 +79,7 @@ public:
     ThreadsafeStatics = 0;
     Blocks = 0;
     EmitAllDecls = 0;
+    MathErrno = 1;
   }
   
   GCMode getGCMode() const { return (GCMode) GC; }