Update the description of the llvm.fmuladd.* intrinsics to avoid use …

…of the

ambiguous term 'legal'.

Suggested by Andrew Booker. Thanks Andrew!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172680 91177308-0d34-0410-b5e6-96231b3b80d8

docs/LangRef.rst

@@ -7689,8 +7689,10 @@ Overview:
 """""""""
 
 The '``llvm.fmuladd.*``' intrinsic functions represent multiply-add
-expressions that can be fused if the code generator determines that the
-fused expression would be legal and efficient.
+expressions that can be fused if the code generator determines that (a) the
+target instruction set has support for a fused operation, and (b) that the
+fused operation is more efficient than the equivalent, separate pair of mul
+and add instructions.
 
 Arguments:
 """"""""""