Add strictfp attribute to prevent unwanted optimizations of libm calls

Differential Revision: https://reviews.llvm.org/D34163

llvm-svn: 310885

1 files changed, 6 insertions, 0 deletions

diff --git a/llvm/docs/LangRef.rst b/llvm/docs/LangRef.rst
index 934c69dde03..f2276905ece 100644
--- a/llvm/docs/LangRef.rst
+++ b/llvm/docs/LangRef.rst
@@ -1644,6 +1644,12 @@ example:
     If a function that has an ``sspstrong`` attribute is inlined into a
     function that doesn't have an ``sspstrong`` attribute, then the
     resulting function will have an ``sspstrong`` attribute.
+``strictfp``
+    This attribute indicates that the function was called from a scope that
+    requires strict floating point semantics.  LLVM will not attempt any
+    optimizations that require assumptions about the floating point rounding
+    mode or that might alter the state of floating point status flags that
+    might otherwise be set or cleared by calling this function.
 ``"thunk"``
     This attribute indicates that the function will delegate to some other
     function with a tail call. The prototype of a thunk should not be used for