Teach InstCombine visitGetElementPtr about address spaces

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188721 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Transforms/InstCombine/InstCombine.h

@@ -212,8 +212,8 @@ class LLVM_LIBRARY_VISIBILITY InstCombiner
   bool ShouldChangeType(Type *From, Type *To) const;
   Value *dyn_castNegVal(Value *V) const;
   Value *dyn_castFNegVal(Value *V, bool NoSignedZero=false) const;
-  Type *FindElementAtOffset(Type *Ty, int64_t Offset,
-                                  SmallVectorImpl<Value*> &NewIndices);
+  Type *FindElementAtOffset(Type *PtrTy, int64_t Offset,
+                            SmallVectorImpl<Value*> &NewIndices);
   Instruction *FoldOpIntoSelect(Instruction &Op, SelectInst *SI);
 
   /// ShouldOptimizeCast - Return true if the cast from "V to Ty" actually

lib/Transforms/InstCombine/InstCombineCasts.cpp

@@ -1385,9 +1385,10 @@ Instruction *InstCombiner::commonPointerCastTransforms(CastInst &CI) {
         GEP->accumulateConstantOffset(*TD, Offset)) {
       // Get the base pointer input of the bitcast, and the type it points to.
       Value *OrigBase = BCI->getOperand(0);
-      Type *GEPIdxTy = OrigBase->getType()->getPointerElementType();
       SmallVector<Value*, 8> NewIndices;
-      if (FindElementAtOffset(GEPIdxTy, Offset.getSExtValue(), NewIndices)) {
+      if (FindElementAtOffset(OrigBase->getType(),
+                              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.

lib/Transforms/InstCombine/InstructionCombining.cpp

@@ -755,19 +755,25 @@ Instruction *InstCombiner::FoldOpIntoPhi(Instruction &I) {
   return ReplaceInstUsesWith(I, NewPN);
 }
 
-/// FindElementAtOffset - Given a type and a constant offset, determine whether
-/// or not there is a sequence of GEP indices into the type that will land us at
-/// the specified offset.  If so, fill them into NewIndices and return the
-/// resultant element type, otherwise return null.
-Type *InstCombiner::FindElementAtOffset(Type *Ty, int64_t Offset,
-                                          SmallVectorImpl<Value*> &NewIndices) {
-  if (!TD) return 0;
-  if (!Ty->isSized()) return 0;
+/// FindElementAtOffset - Given a pointer type and a constant offset, determine
+/// whether or not there is a sequence of GEP indices into the pointed type that
+/// will land us at the specified offset.  If so, fill them into NewIndices and
+/// return the resultant element type, otherwise return null.
+Type *InstCombiner::FindElementAtOffset(Type *PtrTy, int64_t Offset,
+                                        SmallVectorImpl<Value*> &NewIndices) {
+  assert(PtrTy->isPtrOrPtrVectorTy());
+
+  if (!TD)
+    return 0;
+
+  Type *Ty = PtrTy->getPointerElementType();
+  if (!Ty->isSized())
+    return 0;
 
   // Start with the index over the outer type.  Note that the type size
   // might be zero (even if the offset isn't zero) if the indexed type
   // is something like [0 x {int, int}]
-  Type *IntPtrTy = TD->getIntPtrType(Ty->getContext());
+  Type *IntPtrTy = TD->getIntPtrType(PtrTy);
   int64_t FirstIdx = 0;
   if (int64_t TySize = TD->getTypeAllocSize(Ty)) {
     FirstIdx = Offset/TySize;
@@ -1235,7 +1241,7 @@ Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
       if (TD && SrcElTy->isArrayTy() &&
           TD->getTypeAllocSize(SrcElTy->getArrayElementType()) ==
           TD->getTypeAllocSize(ResElTy)) {
-        Type *IdxType = TD->getIntPtrType(GEP.getContext());
+        Type *IdxType = TD->getIntPtrType(GEP.getType());
         Value *Idx[2] = { Constant::getNullValue(IdxType), GEP.getOperand(1) };
         Value *NewGEP = GEP.isInBounds() ?
           Builder->CreateInBoundsGEP(StrippedPtr, Idx, GEP.getName()) :
@@ -1260,7 +1266,7 @@ Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
 
           // Earlier transforms ensure that the index has type IntPtrType, which
           // considerably simplifies the logic by eliminating implicit casts.
-          assert(Idx->getType() == TD->getIntPtrType(GEP.getContext()) &&
+          assert(Idx->getType() == TD->getIntPtrType(GEP.getType()) &&
                  "Index not cast to pointer width?");
 
           bool NSW;
@@ -1295,7 +1301,7 @@ Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
 
           // Earlier transforms ensure that the index has type IntPtrType, which
           // considerably simplifies the logic by eliminating implicit casts.
-          assert(Idx->getType() == TD->getIntPtrType(GEP.getContext()) &&
+          assert(Idx->getType() == TD->getIntPtrType(GEP.getType()) &&
                  "Index not cast to pointer width?");
 
           bool NSW;
@@ -1304,7 +1310,7 @@ Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
             // If the multiplication NewIdx * Scale may overflow then the new
             // GEP may not be "inbounds".
             Value *Off[2] = {
-              Constant::getNullValue(TD->getIntPtrType(GEP.getContext())),
+              Constant::getNullValue(TD->getIntPtrType(GEP.getType())),
               NewIdx
             };
 
@@ -1330,7 +1336,7 @@ Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
   if (BitCastInst *BCI = dyn_cast<BitCastInst>(PtrOp)) {
     Value *Operand = BCI->getOperand(0);
     PointerType *OpType = cast<PointerType>(Operand->getType());
-    unsigned OffsetBits = TD->getPointerSizeInBits();
+    unsigned OffsetBits = TD->getPointerTypeSizeInBits(OpType);
     APInt Offset(OffsetBits, 0);
     if (!isa<BitCastInst>(Operand) &&
         GEP.accumulateConstantOffset(*TD, Offset) &&
@@ -1359,8 +1365,7 @@ Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
       // field at Offset in 'A's type.  If so, we can pull the cast through the
       // GEP.
       SmallVector<Value*, 8> NewIndices;
-      Type *InTy = OpType->getElementType();
-      if (FindElementAtOffset(InTy, Offset.getSExtValue(), NewIndices)) {
+      if (FindElementAtOffset(OpType, Offset.getSExtValue(), NewIndices)) {
         Value *NGEP = GEP.isInBounds() ?
           Builder->CreateInBoundsGEP(Operand, NewIndices) :
           Builder->CreateGEP(Operand, NewIndices);

test/Transforms/InstCombine/cast.ll

@@ -1,6 +1,6 @@
 ; Tests to make sure elimination of casts is working correctly
 ; RUN: opt < %s -instcombine -S | FileCheck %s
-target datalayout = "E-p:64:64:64-a0:0:8-f32:32:32-f64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-v64:64:64-v128:128:128-n8:16:32:64"
+target datalayout = "E-p:64:64:64-p1:32:32:32-a0:0:8-f32:32:32-f64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-v64:64:64-v128:128:128-n8:16:32:64"
 
 @inbuf = external global [32832 x i8]           ; <[32832 x i8]*> [#uses=1]
 
@@ -708,6 +708,19 @@ define %s @test68(%s *%p, i64 %i) {
 ; CHECK-NEXT: ret %s
 }
 
+define %s @test68_as1(%s addrspace(1)* %p, i32 %i) {
+; CHECK-LABEL: @test68_as1(
+  %o = mul i32 %i, 12
+  %q = bitcast %s addrspace(1)* %p to i8 addrspace(1)*
+  %pp = getelementptr inbounds i8 addrspace(1)* %q, i32 %o
+; CHECK-NEXT: getelementptr %s addrspace(1)*
+  %r = bitcast i8 addrspace(1)* %pp to %s addrspace(1)*
+  %l = load %s addrspace(1)* %r
+; CHECK-NEXT: load %s addrspace(1)*
+  ret %s %l
+; CHECK-NEXT: ret %s
+}
+
 define double @test69(double *%p, i64 %i) {
 ; CHECK-LABEL: @test69(
   %o = shl nsw i64 %i, 3
@@ -890,6 +903,20 @@ define double @test80([100 x double]* %p, i32 %i) {
 ; CHECK-NEXT: ret double
 }
 
+define double @test80_as1([100 x double] addrspace(1)* %p, i16 %i) {
+; CHECK-LABEL: @test80_as1(
+  %tmp = mul nsw i16 %i, 8
+; CHECK-NEXT: sext i16 %i to i32
+  %q = bitcast [100 x double] addrspace(1)* %p to i8 addrspace(1)*
+  %pp = getelementptr i8 addrspace(1)* %q, i16 %tmp
+; CHECK-NEXT: getelementptr [100 x double] addrspace(1)*
+  %r = bitcast i8 addrspace(1)* %pp to double addrspace(1)*
+  %l = load double addrspace(1)* %r
+; CHECK-NEXT: load double addrspace(1)*
+  ret double %l
+; CHECK-NEXT: ret double
+}
+
 define double @test81(double *%p, float %f) {
   %i = fptosi float %f to i64
   %q = bitcast double* %p to i8*