From d900c6a8b3de655bac138cfdf4b9a85b7e64ec1c Mon Sep 17 00:00:00 2001
From: Robert Bocchino <bocchino@illinois.edu>
Date: Thu, 19 Jan 2006 23:53:23 +0000
Subject: [PATCH] ConstantFoldLoadThroughGEPConstantExpr wasn't handling
 pointers to packed types correctly.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25470 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Transforms/Utils/Local.cpp | 31 ++++++++++++++++++++++---------
 1 file changed, 22 insertions(+), 9 deletions(-)

diff --git a/lib/Transforms/Utils/Local.cpp b/lib/Transforms/Utils/Local.cpp
index f2598c16ce4..9685e94cc19 100644
--- a/lib/Transforms/Utils/Local.cpp
+++ b/lib/Transforms/Utils/Local.cpp
@@ -267,16 +267,29 @@ Constant *llvm::ConstantFoldLoadThroughGEPConstantExpr(Constant *C,
         return 0;
       }
     } else if (ConstantInt *CI = dyn_cast<ConstantInt>(I.getOperand())) {
-      const ArrayType *ATy = cast<ArrayType>(*I);
-      if ((uint64_t)CI->getRawValue() >= ATy->getNumElements()) return 0;
-      if (ConstantArray *CA = dyn_cast<ConstantArray>(C))
-        C = CA->getOperand((unsigned)CI->getRawValue());
-      else if (isa<ConstantAggregateZero>(C))
-        C = Constant::getNullValue(ATy->getElementType());
-      else if (isa<UndefValue>(C))
-        C = UndefValue::get(ATy->getElementType());
-      else
+      if (const ArrayType *ATy = dyn_cast<ArrayType>(*I)) {
+        if ((uint64_t)CI->getRawValue() >= ATy->getNumElements()) return 0;
+        if (ConstantArray *CA = dyn_cast<ConstantArray>(C))
+          C = CA->getOperand((unsigned)CI->getRawValue());
+        else if (isa<ConstantAggregateZero>(C))
+          C = Constant::getNullValue(ATy->getElementType());
+        else if (isa<UndefValue>(C))
+          C = UndefValue::get(ATy->getElementType());
+        else
+          return 0;
+      } else if (const PackedType *PTy = dyn_cast<PackedType>(*I)) {
+        if ((uint64_t)CI->getRawValue() >= PTy->getNumElements()) return 0;
+        if (ConstantPacked *CP = dyn_cast<ConstantPacked>(C))
+          C = CP->getOperand((unsigned)CI->getRawValue());
+        else if (isa<ConstantAggregateZero>(C))
+          C = Constant::getNullValue(PTy->getElementType());
+        else if (isa<UndefValue>(C))
+          C = UndefValue::get(PTy->getElementType());
+        else
+          return 0;
+      } else {
         return 0;
+      }
     } else {
       return 0;
     }
-- 
2.34.1