From 17c5ce914ce1bb9b8583a57c4fd566224104ecc0 Mon Sep 17 00:00:00 2001
From: David Majnemer <david.majnemer@gmail.com>
Date: Wed, 13 Jul 2016 03:42:38 +0000
Subject: [PATCH] [IR] Make getIndexedOffsetInType return a signed result

A GEPed offset can go negative, the result of getIndexedOffsetInType
should according be a signed type.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@275246 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/llvm/IR/DataLayout.h       |  2 +-
 lib/Analysis/ConstantFolding.cpp   |  2 +-
 lib/Analysis/TypeMetadataUtils.cpp |  4 ++--
 lib/IR/DataLayout.cpp              | 10 +++++-----
 4 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/include/llvm/IR/DataLayout.h b/include/llvm/IR/DataLayout.h
index ed71ae7c223..173121b72ff 100644
--- a/include/llvm/IR/DataLayout.h
+++ b/include/llvm/IR/DataLayout.h
@@ -440,7 +440,7 @@ public:
   ///
   /// Note that this takes the element type, not the pointer type.
   /// This is used to implement getelementptr.
-  uint64_t getIndexedOffsetInType(Type *ElemTy, ArrayRef<Value *> Indices) const;
+  int64_t getIndexedOffsetInType(Type *ElemTy, ArrayRef<Value *> Indices) const;
 
   /// \brief Returns a StructLayout object, indicating the alignment of the
   /// struct, its size, and the offsets of its fields.
diff --git a/lib/Analysis/ConstantFolding.cpp b/lib/Analysis/ConstantFolding.cpp
index 0a9d725db58..c6dae24a63b 100644
--- a/lib/Analysis/ConstantFolding.cpp
+++ b/lib/Analysis/ConstantFolding.cpp
@@ -920,7 +920,7 @@ Constant *ConstantFoldInstOperandsImpl(const Value *InstOrCE, Type *DestTy,
   if (Instruction::isCast(Opcode))
     return ConstantFoldCastOperand(Opcode, Ops[0], DestTy, DL);
 
-  if(auto *GEP = dyn_cast<GEPOperator>(InstOrCE)) {
+  if (auto *GEP = dyn_cast<GEPOperator>(InstOrCE)) {
     if (Constant *C = SymbolicallyEvaluateGEP(GEP, Ops, DL, TLI))
       return C;
 
diff --git a/lib/Analysis/TypeMetadataUtils.cpp b/lib/Analysis/TypeMetadataUtils.cpp
index 8d173d77fb6..31e2b42075d 100644
--- a/lib/Analysis/TypeMetadataUtils.cpp
+++ b/lib/Analysis/TypeMetadataUtils.cpp
@@ -41,7 +41,7 @@ findCallsAtConstantOffset(SmallVectorImpl<DevirtCallSite> &DevirtCalls,
 static void
 findLoadCallsAtConstantOffset(Module *M,
                               SmallVectorImpl<DevirtCallSite> &DevirtCalls,
-                              Value *VPtr, uint64_t Offset) {
+                              Value *VPtr, int64_t Offset) {
   for (const Use &U : VPtr->uses()) {
     Value *User = U.getUser();
     if (isa<BitCastInst>(User)) {
@@ -52,7 +52,7 @@ findLoadCallsAtConstantOffset(Module *M,
       // Take into account the GEP offset.
       if (VPtr == GEP->getPointerOperand() && GEP->hasAllConstantIndices()) {
         SmallVector<Value *, 8> Indices(GEP->op_begin() + 1, GEP->op_end());
-        uint64_t GEPOffset = M->getDataLayout().getIndexedOffsetInType(
+        int64_t GEPOffset = M->getDataLayout().getIndexedOffsetInType(
             GEP->getSourceElementType(), Indices);
         findLoadCallsAtConstantOffset(M, DevirtCalls, User, Offset + GEPOffset);
       }
diff --git a/lib/IR/DataLayout.cpp b/lib/IR/DataLayout.cpp
index dc4b8981be7..20a15fb8831 100644
--- a/lib/IR/DataLayout.cpp
+++ b/lib/IR/DataLayout.cpp
@@ -723,9 +723,9 @@ unsigned DataLayout::getLargestLegalIntTypeSizeInBits() const {
   return Max != LegalIntWidths.end() ? *Max : 0;
 }
 
-uint64_t DataLayout::getIndexedOffsetInType(Type *ElemTy,
-                                            ArrayRef<Value *> Indices) const {
-  uint64_t Result = 0;
+int64_t DataLayout::getIndexedOffsetInType(Type *ElemTy,
+                                           ArrayRef<Value *> Indices) const {
+  int64_t Result = 0;
 
   // We can use 0 as the address space as we don't need
   // to get pointer types back from gep_type_iterator.
@@ -735,7 +735,7 @@ uint64_t DataLayout::getIndexedOffsetInType(Type *ElemTy,
     GTE = gep_type_end(ElemTy, AS, Indices);
   for (; GTI != GTE; ++GTI) {
     Value *Idx = GTI.getOperand();
-    if (StructType *STy = dyn_cast<StructType>(*GTI)) {
+    if (auto *STy = dyn_cast<StructType>(*GTI)) {
       assert(Idx->getType()->isIntegerTy(32) && "Illegal struct idx");
       unsigned FieldNo = cast<ConstantInt>(Idx)->getZExtValue();
 
@@ -747,7 +747,7 @@ uint64_t DataLayout::getIndexedOffsetInType(Type *ElemTy,
     } else {
       // Get the array index and the size of each array element.
       if (int64_t arrayIdx = cast<ConstantInt>(Idx)->getSExtValue())
-        Result += (uint64_t)arrayIdx * getTypeAllocSize(GTI.getIndexedType());
+        Result += arrayIdx * getTypeAllocSize(GTI.getIndexedType());
     }
   }