From 3fa82837441d716a225427f7a924f36d21db3a32 Mon Sep 17 00:00:00 2001 From: Rafael Espindola Date: Fri, 13 May 2011 15:18:06 +0000 Subject: [PATCH] Make codegen able to handle values of empty types. This is one way to fix PR9900. I will keep it open until sable is able to comment on it. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131294 91177308-0d34-0410-b5e6-96231b3b80d8 --- include/llvm/Type.h | 3 + .../SelectionDAG/FunctionLoweringInfo.cpp | 4 + .../SelectionDAG/SelectionDAGBuilder.cpp | 35 ++++++-- lib/VMCore/Type.cpp | 19 +++++ test/CodeGen/Generic/zero-sized-array.ll | 81 +++++++++++++++++++ 5 files changed, 136 insertions(+), 6 deletions(-) create mode 100644 test/CodeGen/Generic/zero-sized-array.ll diff --git a/include/llvm/Type.h b/include/llvm/Type.h index 0939d67265b..3bda91d6638 100644 --- a/include/llvm/Type.h +++ b/include/llvm/Type.h @@ -273,6 +273,9 @@ public: /// @brief Determine if this type could be losslessly bitcast to Ty bool canLosslesslyBitCastTo(const Type *Ty) const; + /// isEmptyTy - Return true if this type is empty, that is, it has no + /// elements or all its elements are empty. + bool isEmptyTy() const; /// Here are some useful little methods to query what type derived types are /// Note that all other types can just compare to see if this == Type::xxxTy; diff --git a/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp b/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp index a1e8254189f..2cb16f589a8 100644 --- a/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp +++ b/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp @@ -155,6 +155,10 @@ void FunctionLoweringInfo::set(const Function &fn, MachineFunction &mf) { const PHINode *PN = dyn_cast(I); ++I) { if (PN->use_empty()) continue; + // Skip empty types + if (PN->getType()->isEmptyTy()) + continue; + DebugLoc DL = PN->getDebugLoc(); unsigned PHIReg = ValueMap[PN]; assert(PHIReg && "PHI node does not have an assigned virtual register!"); diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp index 73a44e9e1a2..72a46c99c00 100644 --- a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp +++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp @@ -1175,6 +1175,10 @@ void SelectionDAGBuilder::visitRet(const ReturnInst &I) { /// created for it, emit nodes to copy the value into the virtual /// registers. void SelectionDAGBuilder::CopyToExportRegsIfNeeded(const Value *V) { + // Skip empty types + if (V->getType()->isEmptyTy()) + return; + DenseMap::iterator VMI = FuncInfo.ValueMap.find(V); if (VMI != FuncInfo.ValueMap.end()) { assert(!V->use_empty() && "Unused value assigned virtual registers!"); @@ -2810,16 +2814,18 @@ void SelectionDAGBuilder::visitInsertValue(const InsertValueInst &I) { SmallVector Values(NumAggValues); SDValue Agg = getValue(Op0); - SDValue Val = getValue(Op1); unsigned i = 0; // Copy the beginning value(s) from the original aggregate. for (; i != LinearIndex; ++i) Values[i] = IntoUndef ? DAG.getUNDEF(AggValueVTs[i]) : SDValue(Agg.getNode(), Agg.getResNo() + i); // Copy values from the inserted value(s). - for (; i != LinearIndex + NumValValues; ++i) - Values[i] = FromUndef ? DAG.getUNDEF(AggValueVTs[i]) : - SDValue(Val.getNode(), Val.getResNo() + i - LinearIndex); + if (NumValValues) { + SDValue Val = getValue(Op1); + for (; i != LinearIndex + NumValValues; ++i) + Values[i] = FromUndef ? DAG.getUNDEF(AggValueVTs[i]) : + SDValue(Val.getNode(), Val.getResNo() + i - LinearIndex); + } // Copy remaining value(s) from the original aggregate. for (; i != NumAggValues; ++i) Values[i] = IntoUndef ? DAG.getUNDEF(AggValueVTs[i]) : @@ -2842,6 +2848,13 @@ void SelectionDAGBuilder::visitExtractValue(const ExtractValueInst &I) { ComputeValueVTs(TLI, ValTy, ValValueVTs); unsigned NumValValues = ValValueVTs.size(); + + // Ignore a extractvalue that produces an empty object + if (!NumValValues) { + setValue(&I, DAG.getUNDEF(MVT(MVT::Other))); + return; + } + SmallVector Values(NumValValues); SDValue Agg = getValue(Op0); @@ -4827,8 +4840,14 @@ void SelectionDAGBuilder::LowerCallTo(ImmutableCallSite CS, SDValue Callee, for (ImmutableCallSite::arg_iterator i = CS.arg_begin(), e = CS.arg_end(); i != e; ++i) { - SDValue ArgNode = getValue(*i); - Entry.Node = ArgNode; Entry.Ty = (*i)->getType(); + const Value *V = *i; + + // Skip empty types + if (V->getType()->isEmptyTy()) + continue; + + SDValue ArgNode = getValue(V); + Entry.Node = ArgNode; Entry.Ty = V->getType(); unsigned attrInd = i - CS.arg_begin() + 1; Entry.isSExt = CS.paramHasAttr(attrInd, Attribute::SExt); @@ -6498,6 +6517,10 @@ SelectionDAGBuilder::HandlePHINodesInSuccessorBlocks(const BasicBlock *LLVMBB) { // Ignore dead phi's. if (PN->use_empty()) continue; + // Skip empty types + if (PN->getType()->isEmptyTy()) + continue; + unsigned Reg; const Value *PHIOp = PN->getIncomingValueForBlock(LLVMBB); diff --git a/lib/VMCore/Type.cpp b/lib/VMCore/Type.cpp index b15304cc959..e4496db4317 100644 --- a/lib/VMCore/Type.cpp +++ b/lib/VMCore/Type.cpp @@ -197,6 +197,25 @@ bool Type::canLosslesslyBitCastTo(const Type *Ty) const { return false; // Other types have no identity values } +bool Type::isEmptyTy() const { + const ArrayType *ATy = dyn_cast(this); + if (ATy) { + unsigned NumElements = ATy->getNumElements(); + return NumElements == 0 || ATy->getElementType()->isEmptyTy(); + } + + const StructType *STy = dyn_cast(this); + if (STy) { + unsigned NumElements = STy->getNumElements(); + for (unsigned i = 0; i < NumElements; ++i) + if (!STy->getElementType(i)->isEmptyTy()) + return false; + return true; + } + + return false; +} + unsigned Type::getPrimitiveSizeInBits() const { switch (getTypeID()) { case Type::FloatTyID: return 32; diff --git a/test/CodeGen/Generic/zero-sized-array.ll b/test/CodeGen/Generic/zero-sized-array.ll new file mode 100644 index 00000000000..280ba0019b6 --- /dev/null +++ b/test/CodeGen/Generic/zero-sized-array.ll @@ -0,0 +1,81 @@ +; RUN: llc < %s +; PR9900 + +%zero = type [0 x i8] +%foobar = type { i32, %zero } + +define void @f(%foobar %arg) { + %arg1 = extractvalue %foobar %arg, 0 + %arg2 = extractvalue %foobar %arg, 1 + call i32 @f2(%zero %arg2, i32 5, i32 42) + ret void +} + +define i32 @f2(%zero %x, i32 %y, i32 %z) { + ret i32 %y +} + +define void @f3(%zero %x, i32 %y) { + call i32 @f2(%zero %x, i32 5, i32 %y) + ret void +} + +define void @f4(%zero %z) { + insertvalue %foobar undef, %zero %z, 1 + ret void +} + +define void @f5(%foobar %x) { +allocas: + %y = extractvalue %foobar %x, 1 + br label %b1 + +b1: + %insert120 = insertvalue %foobar undef, %zero %y, 1 + ret void +} + +define void @f6(%zero %x, %zero %y) { +b1: + br i1 undef, label %end, label %b2 + +b2: + br label %end + +end: + %z = phi %zero [ %y, %b1 ], [ %x, %b2 ] + call void @f4(%zero %z) + ret void +} + +%zero2 = type {} + +define i32 @g1(%zero2 %x, i32 %y, i32 %z) { + ret i32 %y +} + +define void @g2(%zero2 %x, i32 %y) { + call i32 @g1(%zero2 %x, i32 5, i32 %y) + ret void +} + +%zero2r = type {%zero2} + +define i32 @h1(%zero2r %x, i32 %y, i32 %z) { + ret i32 %y +} + +define void @h2(%zero2r %x, i32 %y) { + call i32 @h1(%zero2r %x, i32 5, i32 %y) + ret void +} + +%foobar2 = type { i32, %zero2r } + +define void @h3(%foobar2 %arg) { + %arg1 = extractvalue %foobar2 %arg, 0 + %arg2 = extractvalue %foobar2 %arg, 1 + %arg21 = extractvalue %zero2r %arg2, 0 + call void @g2(%zero2 %arg21, i32 5) + ret void +}