convert a bunch of callers from DataLayout::getIndexedOffset() to GEP::accumulateConstantOffset().

The later API is nicer than the former, and is correct regarding wrap-around offsets (if anyone cares).
There are a few more places left with duplicated code, which I'll remove soon.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171259 91177308-0d34-0410-b5e6-96231b3b80d8

8 files changed, 30 insertions, 83 deletions

diff --git a/lib/Analysis/MemoryBuiltins.cpp b/lib/Analysis/MemoryBuiltins.cpp
index 6fbb374268..cfd8fcfdb7 100644
--- a/lib/Analysis/MemoryBuiltins.cpp
+++ b/lib/Analysis/MemoryBuiltins.cpp
@@ -510,11 +510,10 @@ ObjectSizeOffsetVisitor::visitExtractValueInst(ExtractValueInst&) {
 
 SizeOffsetType ObjectSizeOffsetVisitor::visitGEPOperator(GEPOperator &GEP) {
   SizeOffsetType PtrData = compute(GEP.getPointerOperand());
-  if (!bothKnown(PtrData) || !GEP.hasAllConstantIndices())
+  APInt Offset(IntTyBits, 0);
+  if (!bothKnown(PtrData) || !GEP.accumulateConstantOffset(*TD, Offset))
     return unknown();
 
-  SmallVector<Value*, 8> Ops(GEP.idx_begin(), GEP.idx_end());
-  APInt Offset(IntTyBits,TD->getIndexedOffset(GEP.getPointerOperandType(),Ops));
   return std::make_pair(PtrData.first, PtrData.second + Offset);
 }
 
diff --git a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
index 475b82557d..3680b684c9 100644
--- a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -36,6 +36,7 @@
 #include "llvm/MC/MCStreamer.h"
 #include "llvm/MC/MCSymbol.h"
 #include "llvm/Module.h"
+#include "llvm/Operator.h"
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/Format.h"
 #include "llvm/Support/MathExtras.h"
@@ -1477,19 +1478,14 @@ static const MCExpr *lowerConstant(const Constant *CV, AsmPrinter &AP) {
   case Instruction::GetElementPtr: {
     const DataLayout &TD = *AP.TM.getDataLayout();
     // Generate a symbolic expression for the byte address
-    const Constant *PtrVal = CE->getOperand(0);
-    SmallVector<Value*, 8> IdxVec(CE->op_begin()+1, CE->op_end());
-    int64_t Offset = TD.getIndexedOffset(PtrVal->getType(), IdxVec);
+    APInt OffsetAI(TD.getPointerSizeInBits(), 0);
+    cast<GEPOperator>(CE)->accumulateConstantOffset(TD, OffsetAI);
 
     const MCExpr *Base = lowerConstant(CE->getOperand(0), AP);
-    if (Offset == 0)
+    if (!OffsetAI)
       return Base;
 
-    // Truncate/sext the offset to the pointer size.
-    unsigned Width = TD.getPointerSizeInBits();
-    if (Width < 64)
-      Offset = SignExtend64(Offset, Width);
-
+    int64_t Offset = OffsetAI.getSExtValue();
     return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx),
                                    Ctx);
   }
diff --git a/lib/ExecutionEngine/ExecutionEngine.cpp b/lib/ExecutionEngine/ExecutionEngine.cpp
index 21e0ad3fcd..c2a22e6b3f 100644
--- a/lib/ExecutionEngine/ExecutionEngine.cpp
+++ b/lib/ExecutionEngine/ExecutionEngine.cpp
@@ -21,6 +21,7 @@
 #include "llvm/DerivedTypes.h"
 #include "llvm/ExecutionEngine/GenericValue.h"
 #include "llvm/Module.h"
+#include "llvm/Operator.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/DynamicLibrary.h"
 #include "llvm/Support/ErrorHandling.h"
@@ -555,11 +556,11 @@ GenericValue ExecutionEngine::getConstantValue(const Constant *C) {
     case Instruction::GetElementPtr: {
       // Compute the index
       GenericValue Result = getConstantValue(Op0);
-      SmallVector<Value*, 8> Indices(CE->op_begin()+1, CE->op_end());
-      uint64_t Offset = TD->getIndexedOffset(Op0->getType(), Indices);
+      APInt Offset(TD->getPointerSizeInBits(), 0);
+      cast<GEPOperator>(CE)->accumulateConstantOffset(*TD, Offset);
 
       char* tmp = (char*) Result.PointerVal;
-      Result = PTOGV(tmp + Offset);
+      Result = PTOGV(tmp + Offset.getSExtValue());
       return Result;
     }
     case Instruction::Trunc: {
diff --git a/lib/Target/NVPTX/NVPTXAsmPrinter.cpp b/lib/Target/NVPTX/NVPTXAsmPrinter.cpp
index 14c6a60acf..ad92bdb6ca 100644
--- a/lib/Target/NVPTX/NVPTXAsmPrinter.cpp
+++ b/lib/Target/NVPTX/NVPTXAsmPrinter.cpp
@@ -35,6 +35,7 @@
 #include "llvm/MC/MCStreamer.h"
 #include "llvm/MC/MCSymbol.h"
 #include "llvm/Module.h"
+#include "llvm/Operator.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/FormattedStream.h"
@@ -164,20 +165,14 @@ const MCExpr *nvptx::LowerConstant(const Constant *CV, AsmPrinter &AP) {
   case Instruction::GetElementPtr: {
     const DataLayout &TD = *AP.TM.getDataLayout();
     // Generate a symbolic expression for the byte address
-    const Constant *PtrVal = CE->getOperand(0);
-    SmallVector<Value*, 8> IdxVec(CE->op_begin()+1, CE->op_end());
-    int64_t Offset = TD.getIndexedOffset(PtrVal->getType(), IdxVec);
+    APInt OffsetAI(TD.getPointerSizeInBits(), 0);
+    cast<GEPOperator>(CE)->accumulateConstantOffset(TD, OffsetAI);
 
     const MCExpr *Base = LowerConstant(CE->getOperand(0), AP);
-    if (Offset == 0)
+    if (!OffsetAI)
       return Base;
 
-    // Truncate/sext the offset to the pointer size.
-    if (TD.getPointerSizeInBits() != 64) {
-      int SExtAmount = 64-TD.getPointerSizeInBits();
-      Offset = (Offset << SExtAmount) >> SExtAmount;
-    }
-
+    int64_t Offset = OffsetAI.getSExtValue();
     return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx),
                                    Ctx);
   }
diff --git a/lib/Transforms/IPO/MergeFunctions.cpp b/lib/Transforms/IPO/MergeFunctions.cpp
index 70345b8334..70b5029efa 100644
--- a/lib/Transforms/IPO/MergeFunctions.cpp
+++ b/lib/Transforms/IPO/MergeFunctions.cpp
@@ -346,13 +346,11 @@ bool FunctionComparator::isEquivalentGEP(const GEPOperator *GEP1,
                                          const GEPOperator *GEP2) {
   // When we have target data, we can reduce the GEP down to the value in bytes
   // added to the address.
-  if (TD && GEP1->hasAllConstantIndices() && GEP2->hasAllConstantIndices()) {
-    SmallVector<Value *, 8> Indices1(GEP1->idx_begin(), GEP1->idx_end());
-    SmallVector<Value *, 8> Indices2(GEP2->idx_begin(), GEP2->idx_end());
-    uint64_t Offset1 = TD->getIndexedOffset(GEP1->getPointerOperandType(),
-                                            Indices1);
-    uint64_t Offset2 = TD->getIndexedOffset(GEP2->getPointerOperandType(),
-                                            Indices2);
+  unsigned BitWidth = TD ? TD->getPointerSizeInBits() : 1;
+  APInt Offset1(BitWidth, 0), Offset2(BitWidth, 0);
+  if (TD &&
+      GEP1->accumulateConstantOffset(*TD, Offset1) &&
+      GEP2->accumulateConstantOffset(*TD, Offset2)) {
     return Offset1 == Offset2;
   }
 
diff --git a/lib/Transforms/InstCombine/InstCombineCasts.cpp b/lib/Transforms/InstCombine/InstCombineCasts.cpp
index 19de62c81f..4be3961c2c 100644
--- a/lib/Transforms/InstCombine/InstCombineCasts.cpp
+++ b/lib/Transforms/InstCombine/InstCombineCasts.cpp
@@ -1337,17 +1337,15 @@ Instruction *InstCombiner::commonPointerCastTransforms(CastInst &CI) {
     // GEP computes a constant offset, see if we can convert these three
     // instructions into fewer.  This typically happens with unions and other
     // non-type-safe code.
+    APInt Offset(TD ? TD->getPointerSizeInBits() : 1, 0);
     if (TD && GEP->hasOneUse() && isa<BitCastInst>(GEP->getOperand(0)) &&
-        GEP->hasAllConstantIndices()) {
-      SmallVector<Value*, 8> Ops(GEP->idx_begin(), GEP->idx_end());
-      int64_t Offset = TD->getIndexedOffset(GEP->getPointerOperandType(), Ops);
-
+        GEP->accumulateConstantOffset(*TD, Offset)) {
       // Get the base pointer input of the bitcast, and the type it points to.
       Value *OrigBase = cast<BitCastInst>(GEP->getOperand(0))->getOperand(0);
       Type *GEPIdxTy =
       cast<PointerType>(OrigBase->getType())->getElementType();
       SmallVector<Value*, 8> NewIndices;
-      if (FindElementAtOffset(GEPIdxTy, Offset, NewIndices)) {
+      if (FindElementAtOffset(GEPIdxTy, Offset.getSExtValue(), NewIndices)) {
         // If we were able to index down into an element, create the GEP
         // and bitcast the result.  This eliminates one bitcast, potentially
         // two.
diff --git a/lib/Transforms/InstCombine/InstructionCombining.cpp b/lib/Transforms/InstCombine/InstructionCombining.cpp
index 9da58d0e71..7b21b2ba42 100644
--- a/lib/Transforms/InstCombine/InstructionCombining.cpp
+++ b/lib/Transforms/InstCombine/InstructionCombining.cpp
@@ -1309,17 +1309,15 @@ Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
   /// into a gep of the original struct.  This is important for SROA and alias
   /// analysis of unions.  If "A" is also a bitcast, wait for A/X to be merged.
   if (BitCastInst *BCI = dyn_cast<BitCastInst>(PtrOp)) {
+    APInt Offset(TD ? TD->getPointerSizeInBits() : 1, 0);
     if (TD &&
-        !isa<BitCastInst>(BCI->getOperand(0)) && GEP.hasAllConstantIndices() &&
+        !isa<BitCastInst>(BCI->getOperand(0)) &&
+        GEP.accumulateConstantOffset(*TD, Offset) &&
         StrippedPtrTy->getAddressSpace() == GEP.getPointerAddressSpace()) {
 
-      // Determine how much the GEP moves the pointer.
-      SmallVector<Value*, 8> Ops(GEP.idx_begin(), GEP.idx_end());
-      int64_t Offset = TD->getIndexedOffset(GEP.getPointerOperandType(), Ops);
-
       // If this GEP instruction doesn't move the pointer, just replace the GEP
       // with a bitcast of the real input to the dest type.
-      if (Offset == 0) {
+      if (!Offset) {
         // If the bitcast is of an allocation, and the allocation will be
         // converted to match the type of the cast, don't touch this.
         if (isa<AllocaInst>(BCI->getOperand(0)) ||
@@ -1343,7 +1341,7 @@ Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
       SmallVector<Value*, 8> NewIndices;
       Type *InTy =
         cast<PointerType>(BCI->getOperand(0)->getType())->getElementType();
-      if (FindElementAtOffset(InTy, Offset, NewIndices)) {
+      if (FindElementAtOffset(InTy, Offset.getSExtValue(), NewIndices)) {
         Value *NGEP = GEP.isInBounds() ?
           Builder->CreateInBoundsGEP(BCI->getOperand(0), NewIndices) :
           Builder->CreateGEP(BCI->getOperand(0), NewIndices);
diff --git a/lib/Transforms/Scalar/SROA.cpp b/lib/Transforms/Scalar/SROA.cpp
index 11dd04951d..e73be5c04c 100644
--- a/lib/Transforms/Scalar/SROA.cpp
+++ b/lib/Transforms/Scalar/SROA.cpp
@@ -1642,44 +1642,6 @@ private:
 };
 }
 
-/// \brief Accumulate the constant offsets in a GEP into a single APInt offset.
-///
-/// If the provided GEP is all-constant, the total byte offset formed by the
-/// GEP is computed and Offset is set to it. If the GEP has any non-constant
-/// operands, the function returns false and the value of Offset is unmodified.
-static bool accumulateGEPOffsets(const DataLayout &TD, GEPOperator &GEP,
-                                 APInt &Offset) {
-  APInt GEPOffset(Offset.getBitWidth(), 0);
-  for (gep_type_iterator GTI = gep_type_begin(GEP), GTE = gep_type_end(GEP);
-       GTI != GTE; ++GTI) {
-    ConstantInt *OpC = dyn_cast<ConstantInt>(GTI.getOperand());
-    if (!OpC)
-      return false;
-    if (OpC->isZero()) continue;
-
-    // Handle a struct index, which adds its field offset to the pointer.
-    if (StructType *STy = dyn_cast<StructType>(*GTI)) {
-      unsigned ElementIdx = OpC->getZExtValue();
-      const StructLayout *SL = TD.getStructLayout(STy);
-      GEPOffset += APInt(Offset.getBitWidth(),
-                         SL->getElementOffset(ElementIdx));
-      continue;
-    }
-
-    APInt TypeSize(Offset.getBitWidth(),
-                   TD.getTypeAllocSize(GTI.getIndexedType()));
-    if (VectorType *VTy = dyn_cast<VectorType>(*GTI)) {
-      assert((TD.getTypeSizeInBits(VTy->getScalarType()) % 8) == 0 &&
-             "vector element size is not a multiple of 8, cannot GEP over it");
-      TypeSize = TD.getTypeSizeInBits(VTy->getScalarType()) / 8;
-    }
-
-    GEPOffset += OpC->getValue().sextOrTrunc(Offset.getBitWidth()) * TypeSize;
-  }
-  Offset = GEPOffset;
-  return true;
-}
-
 /// \brief Build a GEP out of a base pointer and indices.
 ///
 /// This will return the BasePtr if that is valid, or build a new GEP
@@ -1882,7 +1844,7 @@ static Value *getAdjustedPtr(IRBuilder<> &IRB, const DataLayout &TD,
     // First fold any existing GEPs into the offset.
     while (GEPOperator *GEP = dyn_cast<GEPOperator>(Ptr)) {
       APInt GEPOffset(Offset.getBitWidth(), 0);
-      if (!accumulateGEPOffsets(TD, *GEP, GEPOffset))
+      if (!GEP->accumulateConstantOffset(TD, GEPOffset))
         break;
       Offset += GEPOffset;
       Ptr = GEP->getPointerOperand();