Fix issue with invalid flat operand number

Avoid iterating over list of operands beyond the number of operands in it.

llvm-svn: 167634

1 files changed, 6 insertions, 1 deletions

diff --git a/llvm/utils/TableGen/CodeEmitterGen.cpp b/llvm/utils/TableGen/CodeEmitterGen.cpp
index e60aec95..bcca15c 100644
--- a/llvm/utils/TableGen/CodeEmitterGen.cpp
+++ b/llvm/utils/TableGen/CodeEmitterGen.cpp
@@ -134,10 +134,15 @@ AddCodeToMergeInOperand(Record *R, BitsInit *BI, const std::string &VarName,
     assert(!CGI.Operands.isFlatOperandNotEmitted(OpIdx) &&
            "Explicitly used operand also marked as not emitted!");
   } else {
+    unsigned NumberOps = CGI.Operands.size();
     /// If this operand is not supposed to be emitted by the
     /// generated emitter, skip it.
-    while (CGI.Operands.isFlatOperandNotEmitted(NumberedOp))
+    while (NumberedOp < NumberOps &&
+           CGI.Operands.isFlatOperandNotEmitted(NumberedOp))
       ++NumberedOp;
+    // If this operand has not been found, ignore it.
+    if (NumberedOp >= NumberOps)
+      return;
     OpIdx = NumberedOp++;
   }