GlobalISel: Fix out of bounds crashes in verifier

llvm-svn: 351769

1 files changed, 8 insertions, 3 deletions

diff --git a/llvm/lib/CodeGen/MachineVerifier.cpp b/llvm/lib/CodeGen/MachineVerifier.cpp
index cc8f77e823d..b7e0f575406 100644
--- a/llvm/lib/CodeGen/MachineVerifier.cpp
+++ b/llvm/lib/CodeGen/MachineVerifier.cpp
@@ -940,9 +940,12 @@ void MachineVerifier::visitMachineInstrBefore(const MachineInstr *MI) {
     if (isFunctionSelected)
       report("Unexpected generic instruction in a Selected function", MI);
 
+    unsigned NumOps = MI->getNumOperands();
+
     // Check types.
     SmallVector<LLT, 4> Types;
-    for (unsigned I = 0; I < MCID.getNumOperands(); ++I) {
+    for (unsigned I = 0, E = std::min(MCID.getNumOperands(), NumOps);
+         I != E; ++I) {
       if (!MCID.OpInfo[I].isGenericType())
         continue;
       // Generic instructions specify type equality constraints between some of
@@ -973,6 +976,10 @@ void MachineVerifier::visitMachineInstrBefore(const MachineInstr *MI) {
       if (MO->isReg() && TargetRegisterInfo::isPhysicalRegister(MO->getReg()))
         report("Generic instruction cannot have physical register", MO, I);
     }
+
+    // Avoid out of bounds in checks below. This was already reported earlier.
+    if (MI->getNumOperands() < MCID.getNumOperands())
+      return;
   }
 
   StringRef ErrorInfo;
@@ -1033,8 +1040,6 @@ void MachineVerifier::visitMachineInstrBefore(const MachineInstr *MI) {
     // instructions aren't guaranteed to have the right number of operands or
     // types attached to them at this point
     assert(MCID.getNumOperands() == 2 && "Expected 2 operands G_*{EXT,TRUNC}");
-    if (MI->getNumOperands() < MCID.getNumOperands())
-      break;
     LLT DstTy = MRI->getType(MI->getOperand(0).getReg());
     LLT SrcTy = MRI->getType(MI->getOperand(1).getReg());
     if (!DstTy.isValid() || !SrcTy.isValid())