From f6eb7e3175aa0bb69152196bff69beade5fb8f38 Mon Sep 17 00:00:00 2001 From: Jingyue Wu Date: Sun, 15 Jun 2014 21:40:57 +0000 Subject: [PATCH] Canonicalize addrspacecast ConstExpr between different pointer types As a follow-up to r210375 which canonicalizes addrspacecast instructions, this patch canonicalizes addrspacecast constant expressions. Given clang uses ConstantExpr::getAddrSpaceCast to emit addrspacecast cosntant expressions, this patch is also a step towards having the frontend emit canonicalized addrspacecasts. Piggyback a minor refactor in InstCombineCasts.cpp Update three affected tests in addrspacecast-alias.ll, access-non-generic.ll and constant-fold-gep.ll and added one new test in constant-fold-address-space-pointer.ll git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211004 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/IR/ConstantFold.cpp | 5 ++++- lib/IR/Constants.cpp | 13 +++++++++++++ lib/Transforms/InstCombine/InstCombineCasts.cpp | 6 ++++-- test/Assembler/addrspacecast-alias.ll | 2 +- test/CodeGen/NVPTX/access-non-generic.ll | 8 ++++---- test/Other/constant-fold-gep.ll | 2 +- .../constant-fold-address-space-pointer.ll | 10 ++++++++++ 7 files changed, 37 insertions(+), 9 deletions(-) diff --git a/lib/IR/ConstantFold.cpp b/lib/IR/ConstantFold.cpp index 706e66fb422..c23ab71eaf3 100644 --- a/lib/IR/ConstantFold.cpp +++ b/lib/IR/ConstantFold.cpp @@ -529,7 +529,10 @@ Constant *llvm::ConstantFoldCastInstruction(unsigned opc, Constant *V, // Try hard to fold cast of cast because they are often eliminable. if (unsigned newOpc = foldConstantCastPair(opc, CE, DestTy)) return ConstantExpr::getCast(newOpc, CE->getOperand(0), DestTy); - } else if (CE->getOpcode() == Instruction::GetElementPtr) { + } else if (CE->getOpcode() == Instruction::GetElementPtr && + // Do not fold addrspacecast (gep 0, .., 0). It might make the + // addrspacecast uncanonicalized. + opc != Instruction::AddrSpaceCast) { // If all of the indexes in the GEP are null values, there is no pointer // adjustment going on. We might as well cast the source pointer. bool isAllNull = true; diff --git a/lib/IR/Constants.cpp b/lib/IR/Constants.cpp index bb8d60b234f..aa26cff6a7b 100644 --- a/lib/IR/Constants.cpp +++ b/lib/IR/Constants.cpp @@ -1698,6 +1698,19 @@ Constant *ConstantExpr::getAddrSpaceCast(Constant *C, Type *DstTy) { assert(CastInst::castIsValid(Instruction::AddrSpaceCast, C, DstTy) && "Invalid constantexpr addrspacecast!"); + // Canonicalize addrspacecasts between different pointer types by first + // bitcasting the pointer type and then converting the address space. + PointerType *SrcScalarTy = cast(C->getType()->getScalarType()); + PointerType *DstScalarTy = cast(DstTy->getScalarType()); + Type *DstElemTy = DstScalarTy->getElementType(); + if (SrcScalarTy->getElementType() != DstElemTy) { + Type *MidTy = PointerType::get(DstElemTy, SrcScalarTy->getAddressSpace()); + if (VectorType *VT = dyn_cast(DstTy)) { + // Handle vectors of pointers. + MidTy = VectorType::get(MidTy, VT->getNumElements()); + } + C = getBitCast(C, MidTy); + } return getFoldedCast(Instruction::AddrSpaceCast, C, DstTy); } diff --git a/lib/Transforms/InstCombine/InstCombineCasts.cpp b/lib/Transforms/InstCombine/InstCombineCasts.cpp index 1b331d118f6..ff083d7926c 100644 --- a/lib/Transforms/InstCombine/InstCombineCasts.cpp +++ b/lib/Transforms/InstCombine/InstCombineCasts.cpp @@ -1919,8 +1919,10 @@ Instruction *InstCombiner::visitAddrSpaceCast(AddrSpaceCastInst &CI) { Type *DestElemTy = DestTy->getElementType(); if (SrcTy->getElementType() != DestElemTy) { Type *MidTy = PointerType::get(DestElemTy, SrcTy->getAddressSpace()); - if (CI.getType()->isVectorTy()) // Handle vectors of pointers. - MidTy = VectorType::get(MidTy, CI.getType()->getVectorNumElements()); + if (VectorType *VT = dyn_cast(CI.getType())) { + // Handle vectors of pointers. + MidTy = VectorType::get(MidTy, VT->getNumElements()); + } Value *NewBitCast = Builder->CreateBitCast(Src, MidTy); return new AddrSpaceCastInst(NewBitCast, CI.getType()); diff --git a/test/Assembler/addrspacecast-alias.ll b/test/Assembler/addrspacecast-alias.ll index 7d00ac4f8f3..d7516599dfe 100644 --- a/test/Assembler/addrspacecast-alias.ll +++ b/test/Assembler/addrspacecast-alias.ll @@ -4,4 +4,4 @@ @i = internal addrspace(1) global i8 42 @ia = alias internal addrspacecast (i8 addrspace(1)* @i to i8 addrspace(2)* addrspace(3)*) -; CHECK: @ia = alias internal addrspacecast (i8 addrspace(1)* @i to i8 addrspace(2)* addrspace(3)*) +; CHECK: @ia = alias internal addrspacecast (i8 addrspace(2)* addrspace(1)* bitcast (i8 addrspace(1)* @i to i8 addrspace(2)* addrspace(1)*) to i8 addrspace(2)* addrspace(3)*) diff --git a/test/CodeGen/NVPTX/access-non-generic.ll b/test/CodeGen/NVPTX/access-non-generic.ll index 0622aa3cb5f..c225abf0fd8 100644 --- a/test/CodeGen/NVPTX/access-non-generic.ll +++ b/test/CodeGen/NVPTX/access-non-generic.ll @@ -74,13 +74,13 @@ define float @ld_st_shared_f32(i32 %i, float %v) { ret float %sum5 } -; Verifies nvptx-favor-non-generic keeps addrspacecasts between pointers of -; different element types. +; When hoisting an addrspacecast between different pointer types, replace the +; addrspacecast with a bitcast. define i32 @ld_int_from_float() { ; IR-LABEL: @ld_int_from_float -; IR: addrspacecast +; IR: load i32 addrspace(3)* bitcast (float addrspace(3)* @scalar to i32 addrspace(3)*) ; PTX-LABEL: ld_int_from_float( -; PTX: cvta.shared.u{{(32|64)}} +; PTX: ld.shared.u{{(32|64)}} %1 = load i32* addrspacecast(float addrspace(3)* @scalar to i32*), align 4 ret i32 %1 } diff --git a/test/Other/constant-fold-gep.ll b/test/Other/constant-fold-gep.ll index aed4145c550..dc122fd1610 100644 --- a/test/Other/constant-fold-gep.ll +++ b/test/Other/constant-fold-gep.ll @@ -457,7 +457,7 @@ define i8* @different_addrspace() nounwind noinline { %p = getelementptr inbounds i8* addrspacecast ([4 x i8] addrspace(12)* @p12 to i8*), i32 2 ret i8* %p -; OPT: ret i8* getelementptr (i8* addrspacecast ([4 x i8] addrspace(12)* @p12 to i8*), i32 2) +; OPT: ret i8* getelementptr (i8* addrspacecast (i8 addrspace(12)* getelementptr inbounds ([4 x i8] addrspace(12)* @p12, i32 0, i32 0) to i8*), i32 2) } define i8* @same_addrspace() nounwind noinline { diff --git a/test/Transforms/InstCombine/constant-fold-address-space-pointer.ll b/test/Transforms/InstCombine/constant-fold-address-space-pointer.ll index 9f21d5419b7..7fac78a40f5 100644 --- a/test/Transforms/InstCombine/constant-fold-address-space-pointer.ll +++ b/test/Transforms/InstCombine/constant-fold-address-space-pointer.ll @@ -230,3 +230,13 @@ define i32 @constant_through_array_as_ptrs() { %b = load i32 addrspace(1)* %a, align 4 ret i32 %b } + +@shared_mem = external addrspace(3) global [0 x i8] + +define float @canonicalize_addrspacecast(i32 %i) { +; CHECK-LABEL: @canonicalize_addrspacecast +; CHECK-NEXT: getelementptr inbounds float* addrspacecast (float addrspace(3)* bitcast ([0 x i8] addrspace(3)* @shared_mem to float addrspace(3)*) to float*), i32 %i + %p = getelementptr inbounds float* addrspacecast ([0 x i8] addrspace(3)* @shared_mem to float*), i32 %i + %v = load float* %p + ret float %v +} -- 2.34.1