[llvm] r188448 - Tentative fix for global-buffer-overflow caused by r188426. Found by AddressSanitizer

[Alexey Samsonov]

Author: samsonov
Date: Thu Aug 15 02:11:34 2013
New Revision: 188448

URL: http://llvm.org/viewvc/llvm-project?rev=188448&view=rev
Log:
Tentative fix for global-buffer-overflow caused by r188426. Found by AddressSanitizer

Modified:
    llvm/trunk/lib/Target/R600/AMDGPUISelDAGToDAG.cpp

Modified: llvm/trunk/lib/Target/R600/AMDGPUISelDAGToDAG.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/R600/AMDGPUISelDAGToDAG.cpp?rev=188448&r1=188447&r2=188448&view=diff
==============================================================================
--- llvm/trunk/lib/Target/R600/AMDGPUISelDAGToDAG.cpp (original)
+++ llvm/trunk/lib/Target/R600/AMDGPUISelDAGToDAG.cpp Thu Aug 15 02:11:34 2013
@@ -115,7 +115,10 @@ const TargetRegisterClass *AMDGPUDAGToDA
   switch (N->getMachineOpcode()) {
   default: {
     const MCInstrDesc &Desc = TM.getInstrInfo()->get(N->getMachineOpcode());
-    int RegClass = Desc.OpInfo[Desc.getNumDefs() + OpNo].RegClass;
+    unsigned OpIdx = Desc.getNumDefs() + OpNo;
+    if (OpIdx >= Desc.getNumOperands())
+      return NULL;
+    int RegClass = Desc.OpInfo[OpIdx].RegClass;
     if (RegClass == -1) {
       return NULL;
     }