Fix spelling/grammar.

llvm-svn: 9023
diff --git a/llvm/lib/VMCore/Instruction.cpp b/llvm/lib/VMCore/Instruction.cpp
index 122e0f7..a2d0ba9 100644
--- a/llvm/lib/VMCore/Instruction.cpp
+++ b/llvm/lib/VMCore/Instruction.cpp
@@ -119,7 +119,7 @@
 
 /// isCommutative - Return true if the instruction is commutative:
 ///
-///   Commutative operators satistify: (x op y) === (y op x)
+///   Commutative operators satisfy: (x op y) === (y op x)
 ///
 /// In LLVM, these are the associative operators, plus SetEQ and SetNE, when
 /// applied to any type.