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author | Dan Gohman <gohman@apple.com> | 2010-04-21 01:22:34 +0000 |
---|---|---|
committer | Dan Gohman <gohman@apple.com> | 2010-04-21 01:22:34 +0000 |
commit | db189c22c8bf5193452582d2a1913b18531ed831 (patch) | |
tree | 8815249891afaebae858de28ca18094a2823bbcf /lib | |
parent | a06f927cf67607bbe8e48ff587c9574b7842d3da (diff) | |
download | external_llvm-db189c22c8bf5193452582d2a1913b18531ed831.zip external_llvm-db189c22c8bf5193452582d2a1913b18531ed831.tar.gz external_llvm-db189c22c8bf5193452582d2a1913b18531ed831.tar.bz2 |
Move several SelectionDAG-independent utility functions out of the
SelectionDAG directory and into a new Analysis.cpp file.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101975 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib')
-rw-r--r-- | lib/CodeGen/Analysis.cpp | 285 | ||||
-rw-r--r-- | lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp | 262 | ||||
-rw-r--r-- | lib/CodeGen/SelectionDAG/FunctionLoweringInfo.h | 49 | ||||
-rw-r--r-- | lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp | 1 |
4 files changed, 287 insertions, 310 deletions
diff --git a/lib/CodeGen/Analysis.cpp b/lib/CodeGen/Analysis.cpp new file mode 100644 index 0000000..f71eee5 --- /dev/null +++ b/lib/CodeGen/Analysis.cpp @@ -0,0 +1,285 @@ +//===-- Analysis.cpp - CodeGen LLVM IR Analysis Utilities --*- C++ ------*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file defines several CodeGen-specific LLVM IR analysis utilties. +// +//===----------------------------------------------------------------------===// + +#include "llvm/CodeGen/Analysis.h" +#include "llvm/DerivedTypes.h" +#include "llvm/Function.h" +#include "llvm/Instructions.h" +#include "llvm/IntrinsicInst.h" +#include "llvm/LLVMContext.h" +#include "llvm/Module.h" +#include "llvm/CodeGen/MachineFunction.h" +#include "llvm/Target/TargetData.h" +#include "llvm/Target/TargetLowering.h" +#include "llvm/Target/TargetOptions.h" +#include "llvm/Support/ErrorHandling.h" +#include "llvm/Support/MathExtras.h" +using namespace llvm; + +/// ComputeLinearIndex - Given an LLVM IR aggregate type and a sequence +/// of insertvalue or extractvalue indices that identify a member, return +/// the linearized index of the start of the member. +/// +unsigned llvm::ComputeLinearIndex(const TargetLowering &TLI, const Type *Ty, + const unsigned *Indices, + const unsigned *IndicesEnd, + unsigned CurIndex) { + // Base case: We're done. + if (Indices && Indices == IndicesEnd) + return CurIndex; + + // Given a struct type, recursively traverse the elements. + if (const StructType *STy = dyn_cast<StructType>(Ty)) { + for (StructType::element_iterator EB = STy->element_begin(), + EI = EB, + EE = STy->element_end(); + EI != EE; ++EI) { + if (Indices && *Indices == unsigned(EI - EB)) + return ComputeLinearIndex(TLI, *EI, Indices+1, IndicesEnd, CurIndex); + CurIndex = ComputeLinearIndex(TLI, *EI, 0, 0, CurIndex); + } + return CurIndex; + } + // Given an array type, recursively traverse the elements. + else if (const ArrayType *ATy = dyn_cast<ArrayType>(Ty)) { + const Type *EltTy = ATy->getElementType(); + for (unsigned i = 0, e = ATy->getNumElements(); i != e; ++i) { + if (Indices && *Indices == i) + return ComputeLinearIndex(TLI, EltTy, Indices+1, IndicesEnd, CurIndex); + CurIndex = ComputeLinearIndex(TLI, EltTy, 0, 0, CurIndex); + } + return CurIndex; + } + // We haven't found the type we're looking for, so keep searching. + return CurIndex + 1; +} + +/// ComputeValueVTs - Given an LLVM IR type, compute a sequence of +/// EVTs that represent all the individual underlying +/// non-aggregate types that comprise it. +/// +/// If Offsets is non-null, it points to a vector to be filled in +/// with the in-memory offsets of each of the individual values. +/// +void llvm::ComputeValueVTs(const TargetLowering &TLI, const Type *Ty, + SmallVectorImpl<EVT> &ValueVTs, + SmallVectorImpl<uint64_t> *Offsets, + uint64_t StartingOffset) { + // Given a struct type, recursively traverse the elements. + if (const StructType *STy = dyn_cast<StructType>(Ty)) { + const StructLayout *SL = TLI.getTargetData()->getStructLayout(STy); + for (StructType::element_iterator EB = STy->element_begin(), + EI = EB, + EE = STy->element_end(); + EI != EE; ++EI) + ComputeValueVTs(TLI, *EI, ValueVTs, Offsets, + StartingOffset + SL->getElementOffset(EI - EB)); + return; + } + // Given an array type, recursively traverse the elements. + if (const ArrayType *ATy = dyn_cast<ArrayType>(Ty)) { + const Type *EltTy = ATy->getElementType(); + uint64_t EltSize = TLI.getTargetData()->getTypeAllocSize(EltTy); + for (unsigned i = 0, e = ATy->getNumElements(); i != e; ++i) + ComputeValueVTs(TLI, EltTy, ValueVTs, Offsets, + StartingOffset + i * EltSize); + return; + } + // Interpret void as zero return values. + if (Ty->isVoidTy()) + return; + // Base case: we can get an EVT for this LLVM IR type. + ValueVTs.push_back(TLI.getValueType(Ty)); + if (Offsets) + Offsets->push_back(StartingOffset); +} + +/// ExtractTypeInfo - Returns the type info, possibly bitcast, encoded in V. +GlobalVariable *llvm::ExtractTypeInfo(Value *V) { + V = V->stripPointerCasts(); + GlobalVariable *GV = dyn_cast<GlobalVariable>(V); + + if (GV && GV->getName() == ".llvm.eh.catch.all.value") { + assert(GV->hasInitializer() && + "The EH catch-all value must have an initializer"); + Value *Init = GV->getInitializer(); + GV = dyn_cast<GlobalVariable>(Init); + if (!GV) V = cast<ConstantPointerNull>(Init); + } + + assert((GV || isa<ConstantPointerNull>(V)) && + "TypeInfo must be a global variable or NULL"); + return GV; +} + +/// hasInlineAsmMemConstraint - Return true if the inline asm instruction being +/// processed uses a memory 'm' constraint. +bool +llvm::hasInlineAsmMemConstraint(std::vector<InlineAsm::ConstraintInfo> &CInfos, + const TargetLowering &TLI) { + for (unsigned i = 0, e = CInfos.size(); i != e; ++i) { + InlineAsm::ConstraintInfo &CI = CInfos[i]; + for (unsigned j = 0, ee = CI.Codes.size(); j != ee; ++j) { + TargetLowering::ConstraintType CType = TLI.getConstraintType(CI.Codes[j]); + if (CType == TargetLowering::C_Memory) + return true; + } + + // Indirect operand accesses access memory. + if (CI.isIndirect) + return true; + } + + return false; +} + +/// getFCmpCondCode - Return the ISD condition code corresponding to +/// the given LLVM IR floating-point condition code. This includes +/// consideration of global floating-point math flags. +/// +ISD::CondCode llvm::getFCmpCondCode(FCmpInst::Predicate Pred) { + ISD::CondCode FPC, FOC; + switch (Pred) { + case FCmpInst::FCMP_FALSE: FOC = FPC = ISD::SETFALSE; break; + case FCmpInst::FCMP_OEQ: FOC = ISD::SETEQ; FPC = ISD::SETOEQ; break; + case FCmpInst::FCMP_OGT: FOC = ISD::SETGT; FPC = ISD::SETOGT; break; + case FCmpInst::FCMP_OGE: FOC = ISD::SETGE; FPC = ISD::SETOGE; break; + case FCmpInst::FCMP_OLT: FOC = ISD::SETLT; FPC = ISD::SETOLT; break; + case FCmpInst::FCMP_OLE: FOC = ISD::SETLE; FPC = ISD::SETOLE; break; + case FCmpInst::FCMP_ONE: FOC = ISD::SETNE; FPC = ISD::SETONE; break; + case FCmpInst::FCMP_ORD: FOC = FPC = ISD::SETO; break; + case FCmpInst::FCMP_UNO: FOC = FPC = ISD::SETUO; break; + case FCmpInst::FCMP_UEQ: FOC = ISD::SETEQ; FPC = ISD::SETUEQ; break; + case FCmpInst::FCMP_UGT: FOC = ISD::SETGT; FPC = ISD::SETUGT; break; + case FCmpInst::FCMP_UGE: FOC = ISD::SETGE; FPC = ISD::SETUGE; break; + case FCmpInst::FCMP_ULT: FOC = ISD::SETLT; FPC = ISD::SETULT; break; + case FCmpInst::FCMP_ULE: FOC = ISD::SETLE; FPC = ISD::SETULE; break; + case FCmpInst::FCMP_UNE: FOC = ISD::SETNE; FPC = ISD::SETUNE; break; + case FCmpInst::FCMP_TRUE: FOC = FPC = ISD::SETTRUE; break; + default: + llvm_unreachable("Invalid FCmp predicate opcode!"); + FOC = FPC = ISD::SETFALSE; + break; + } + if (FiniteOnlyFPMath()) + return FOC; + else + return FPC; +} + +/// getICmpCondCode - Return the ISD condition code corresponding to +/// the given LLVM IR integer condition code. +/// +ISD::CondCode llvm::getICmpCondCode(ICmpInst::Predicate Pred) { + switch (Pred) { + case ICmpInst::ICMP_EQ: return ISD::SETEQ; + case ICmpInst::ICMP_NE: return ISD::SETNE; + case ICmpInst::ICMP_SLE: return ISD::SETLE; + case ICmpInst::ICMP_ULE: return ISD::SETULE; + case ICmpInst::ICMP_SGE: return ISD::SETGE; + case ICmpInst::ICMP_UGE: return ISD::SETUGE; + case ICmpInst::ICMP_SLT: return ISD::SETLT; + case ICmpInst::ICMP_ULT: return ISD::SETULT; + case ICmpInst::ICMP_SGT: return ISD::SETGT; + case ICmpInst::ICMP_UGT: return ISD::SETUGT; + default: + llvm_unreachable("Invalid ICmp predicate opcode!"); + return ISD::SETNE; + } +} + +/// Test if the given instruction is in a position to be optimized +/// with a tail-call. This roughly means that it's in a block with +/// a return and there's nothing that needs to be scheduled +/// between it and the return. +/// +/// This function only tests target-independent requirements. +bool llvm::isInTailCallPosition(ImmutableCallSite CS, Attributes CalleeRetAttr, + const TargetLowering &TLI) { + const Instruction *I = CS.getInstruction(); + const BasicBlock *ExitBB = I->getParent(); + const TerminatorInst *Term = ExitBB->getTerminator(); + const ReturnInst *Ret = dyn_cast<ReturnInst>(Term); + const Function *F = ExitBB->getParent(); + + // The block must end in a return statement or unreachable. + // + // FIXME: Decline tailcall if it's not guaranteed and if the block ends in + // an unreachable, for now. The way tailcall optimization is currently + // implemented means it will add an epilogue followed by a jump. That is + // not profitable. Also, if the callee is a special function (e.g. + // longjmp on x86), it can end up causing miscompilation that has not + // been fully understood. + if (!Ret && + (!GuaranteedTailCallOpt || !isa<UnreachableInst>(Term))) return false; + + // If I will have a chain, make sure no other instruction that will have a + // chain interposes between I and the return. + if (I->mayHaveSideEffects() || I->mayReadFromMemory() || + !I->isSafeToSpeculativelyExecute()) + for (BasicBlock::const_iterator BBI = prior(prior(ExitBB->end())); ; + --BBI) { + if (&*BBI == I) + break; + // Debug info intrinsics do not get in the way of tail call optimization. + if (isa<DbgInfoIntrinsic>(BBI)) + continue; + if (BBI->mayHaveSideEffects() || BBI->mayReadFromMemory() || + !BBI->isSafeToSpeculativelyExecute()) + return false; + } + + // If the block ends with a void return or unreachable, it doesn't matter + // what the call's return type is. + if (!Ret || Ret->getNumOperands() == 0) return true; + + // If the return value is undef, it doesn't matter what the call's + // return type is. + if (isa<UndefValue>(Ret->getOperand(0))) return true; + + // Conservatively require the attributes of the call to match those of + // the return. Ignore noalias because it doesn't affect the call sequence. + unsigned CallerRetAttr = F->getAttributes().getRetAttributes(); + if ((CalleeRetAttr ^ CallerRetAttr) & ~Attribute::NoAlias) + return false; + + // It's not safe to eliminate the sign / zero extension of the return value. + if ((CallerRetAttr & Attribute::ZExt) || (CallerRetAttr & Attribute::SExt)) + return false; + + // Otherwise, make sure the unmodified return value of I is the return value. + for (const Instruction *U = dyn_cast<Instruction>(Ret->getOperand(0)); ; + U = dyn_cast<Instruction>(U->getOperand(0))) { + if (!U) + return false; + if (!U->hasOneUse()) + return false; + if (U == I) + break; + // Check for a truly no-op truncate. + if (isa<TruncInst>(U) && + TLI.isTruncateFree(U->getOperand(0)->getType(), U->getType())) + continue; + // Check for a truly no-op bitcast. + if (isa<BitCastInst>(U) && + (U->getOperand(0)->getType() == U->getType() || + (U->getOperand(0)->getType()->isPointerTy() && + U->getType()->isPointerTy()))) + continue; + // Otherwise it's not a true no-op. + return false; + } + + return true; +} + diff --git a/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp b/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp index cc9a3d5..8fe619e 100644 --- a/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp +++ b/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp @@ -14,19 +14,18 @@ #define DEBUG_TYPE "function-lowering-info" #include "FunctionLoweringInfo.h" -#include "llvm/CallingConv.h" #include "llvm/DerivedTypes.h" #include "llvm/Function.h" #include "llvm/Instructions.h" #include "llvm/IntrinsicInst.h" #include "llvm/LLVMContext.h" #include "llvm/Module.h" +#include "llvm/CodeGen/Analysis.h" #include "llvm/CodeGen/MachineFunction.h" #include "llvm/CodeGen/MachineFrameInfo.h" #include "llvm/CodeGen/MachineInstrBuilder.h" #include "llvm/CodeGen/MachineModuleInfo.h" #include "llvm/CodeGen/MachineRegisterInfo.h" -#include "llvm/Analysis/DebugInfo.h" #include "llvm/Target/TargetRegisterInfo.h" #include "llvm/Target/TargetData.h" #include "llvm/Target/TargetFrameInfo.h" @@ -34,92 +33,12 @@ #include "llvm/Target/TargetIntrinsicInfo.h" #include "llvm/Target/TargetLowering.h" #include "llvm/Target/TargetOptions.h" -#include "llvm/Support/Compiler.h" #include "llvm/Support/Debug.h" #include "llvm/Support/ErrorHandling.h" #include "llvm/Support/MathExtras.h" -#include "llvm/Support/raw_ostream.h" #include <algorithm> using namespace llvm; -/// ComputeLinearIndex - Given an LLVM IR aggregate type and a sequence -/// of insertvalue or extractvalue indices that identify a member, return -/// the linearized index of the start of the member. -/// -unsigned llvm::ComputeLinearIndex(const TargetLowering &TLI, const Type *Ty, - const unsigned *Indices, - const unsigned *IndicesEnd, - unsigned CurIndex) { - // Base case: We're done. - if (Indices && Indices == IndicesEnd) - return CurIndex; - - // Given a struct type, recursively traverse the elements. - if (const StructType *STy = dyn_cast<StructType>(Ty)) { - for (StructType::element_iterator EB = STy->element_begin(), - EI = EB, - EE = STy->element_end(); - EI != EE; ++EI) { - if (Indices && *Indices == unsigned(EI - EB)) - return ComputeLinearIndex(TLI, *EI, Indices+1, IndicesEnd, CurIndex); - CurIndex = ComputeLinearIndex(TLI, *EI, 0, 0, CurIndex); - } - return CurIndex; - } - // Given an array type, recursively traverse the elements. - else if (const ArrayType *ATy = dyn_cast<ArrayType>(Ty)) { - const Type *EltTy = ATy->getElementType(); - for (unsigned i = 0, e = ATy->getNumElements(); i != e; ++i) { - if (Indices && *Indices == i) - return ComputeLinearIndex(TLI, EltTy, Indices+1, IndicesEnd, CurIndex); - CurIndex = ComputeLinearIndex(TLI, EltTy, 0, 0, CurIndex); - } - return CurIndex; - } - // We haven't found the type we're looking for, so keep searching. - return CurIndex + 1; -} - -/// ComputeValueVTs - Given an LLVM IR type, compute a sequence of -/// EVTs that represent all the individual underlying -/// non-aggregate types that comprise it. -/// -/// If Offsets is non-null, it points to a vector to be filled in -/// with the in-memory offsets of each of the individual values. -/// -void llvm::ComputeValueVTs(const TargetLowering &TLI, const Type *Ty, - SmallVectorImpl<EVT> &ValueVTs, - SmallVectorImpl<uint64_t> *Offsets, - uint64_t StartingOffset) { - // Given a struct type, recursively traverse the elements. - if (const StructType *STy = dyn_cast<StructType>(Ty)) { - const StructLayout *SL = TLI.getTargetData()->getStructLayout(STy); - for (StructType::element_iterator EB = STy->element_begin(), - EI = EB, - EE = STy->element_end(); - EI != EE; ++EI) - ComputeValueVTs(TLI, *EI, ValueVTs, Offsets, - StartingOffset + SL->getElementOffset(EI - EB)); - return; - } - // Given an array type, recursively traverse the elements. - if (const ArrayType *ATy = dyn_cast<ArrayType>(Ty)) { - const Type *EltTy = ATy->getElementType(); - uint64_t EltSize = TLI.getTargetData()->getTypeAllocSize(EltTy); - for (unsigned i = 0, e = ATy->getNumElements(); i != e; ++i) - ComputeValueVTs(TLI, EltTy, ValueVTs, Offsets, - StartingOffset + i * EltSize); - return; - } - // Interpret void as zero return values. - if (Ty->isVoidTy()) - return; - // Base case: we can get an EVT for this LLVM IR type. - ValueVTs.push_back(TLI.getValueType(Ty)); - if (Offsets) - Offsets->push_back(StartingOffset); -} - /// isUsedOutsideOfDefiningBlock - Return true if this instruction is used by /// PHI nodes or outside of the basic block that defines it, or used by a /// switch or atomic instruction, which may expand to multiple basic blocks. @@ -285,24 +204,6 @@ unsigned FunctionLoweringInfo::CreateRegForValue(const Value *V) { return FirstReg; } -/// ExtractTypeInfo - Returns the type info, possibly bitcast, encoded in V. -GlobalVariable *llvm::ExtractTypeInfo(Value *V) { - V = V->stripPointerCasts(); - GlobalVariable *GV = dyn_cast<GlobalVariable>(V); - - if (GV && GV->getName() == ".llvm.eh.catch.all.value") { - assert(GV->hasInitializer() && - "The EH catch-all value must have an initializer"); - Value *Init = GV->getInitializer(); - GV = dyn_cast<GlobalVariable>(Init); - if (!GV) V = cast<ConstantPointerNull>(Init); - } - - assert((GV || isa<ConstantPointerNull>(V)) && - "TypeInfo must be a global variable or NULL"); - return GV; -} - /// AddCatchInfo - Extract the personality and type infos from an eh.selector /// call, and add them to the specified machine basic block. void llvm::AddCatchInfo(const CallInst &I, MachineModuleInfo *MMI, @@ -370,164 +271,3 @@ void llvm::CopyCatchInfo(const BasicBlock *SrcBB, const BasicBlock *DestBB, #endif } } - -/// hasInlineAsmMemConstraint - Return true if the inline asm instruction being -/// processed uses a memory 'm' constraint. -bool -llvm::hasInlineAsmMemConstraint(std::vector<InlineAsm::ConstraintInfo> &CInfos, - const TargetLowering &TLI) { - for (unsigned i = 0, e = CInfos.size(); i != e; ++i) { - InlineAsm::ConstraintInfo &CI = CInfos[i]; - for (unsigned j = 0, ee = CI.Codes.size(); j != ee; ++j) { - TargetLowering::ConstraintType CType = TLI.getConstraintType(CI.Codes[j]); - if (CType == TargetLowering::C_Memory) - return true; - } - - // Indirect operand accesses access memory. - if (CI.isIndirect) - return true; - } - - return false; -} - -/// getFCmpCondCode - Return the ISD condition code corresponding to -/// the given LLVM IR floating-point condition code. This includes -/// consideration of global floating-point math flags. -/// -ISD::CondCode llvm::getFCmpCondCode(FCmpInst::Predicate Pred) { - ISD::CondCode FPC, FOC; - switch (Pred) { - case FCmpInst::FCMP_FALSE: FOC = FPC = ISD::SETFALSE; break; - case FCmpInst::FCMP_OEQ: FOC = ISD::SETEQ; FPC = ISD::SETOEQ; break; - case FCmpInst::FCMP_OGT: FOC = ISD::SETGT; FPC = ISD::SETOGT; break; - case FCmpInst::FCMP_OGE: FOC = ISD::SETGE; FPC = ISD::SETOGE; break; - case FCmpInst::FCMP_OLT: FOC = ISD::SETLT; FPC = ISD::SETOLT; break; - case FCmpInst::FCMP_OLE: FOC = ISD::SETLE; FPC = ISD::SETOLE; break; - case FCmpInst::FCMP_ONE: FOC = ISD::SETNE; FPC = ISD::SETONE; break; - case FCmpInst::FCMP_ORD: FOC = FPC = ISD::SETO; break; - case FCmpInst::FCMP_UNO: FOC = FPC = ISD::SETUO; break; - case FCmpInst::FCMP_UEQ: FOC = ISD::SETEQ; FPC = ISD::SETUEQ; break; - case FCmpInst::FCMP_UGT: FOC = ISD::SETGT; FPC = ISD::SETUGT; break; - case FCmpInst::FCMP_UGE: FOC = ISD::SETGE; FPC = ISD::SETUGE; break; - case FCmpInst::FCMP_ULT: FOC = ISD::SETLT; FPC = ISD::SETULT; break; - case FCmpInst::FCMP_ULE: FOC = ISD::SETLE; FPC = ISD::SETULE; break; - case FCmpInst::FCMP_UNE: FOC = ISD::SETNE; FPC = ISD::SETUNE; break; - case FCmpInst::FCMP_TRUE: FOC = FPC = ISD::SETTRUE; break; - default: - llvm_unreachable("Invalid FCmp predicate opcode!"); - FOC = FPC = ISD::SETFALSE; - break; - } - if (FiniteOnlyFPMath()) - return FOC; - else - return FPC; -} - -/// getICmpCondCode - Return the ISD condition code corresponding to -/// the given LLVM IR integer condition code. -/// -ISD::CondCode llvm::getICmpCondCode(ICmpInst::Predicate Pred) { - switch (Pred) { - case ICmpInst::ICMP_EQ: return ISD::SETEQ; - case ICmpInst::ICMP_NE: return ISD::SETNE; - case ICmpInst::ICMP_SLE: return ISD::SETLE; - case ICmpInst::ICMP_ULE: return ISD::SETULE; - case ICmpInst::ICMP_SGE: return ISD::SETGE; - case ICmpInst::ICMP_UGE: return ISD::SETUGE; - case ICmpInst::ICMP_SLT: return ISD::SETLT; - case ICmpInst::ICMP_ULT: return ISD::SETULT; - case ICmpInst::ICMP_SGT: return ISD::SETGT; - case ICmpInst::ICMP_UGT: return ISD::SETUGT; - default: - llvm_unreachable("Invalid ICmp predicate opcode!"); - return ISD::SETNE; - } -} - -/// Test if the given instruction is in a position to be optimized -/// with a tail-call. This roughly means that it's in a block with -/// a return and there's nothing that needs to be scheduled -/// between it and the return. -/// -/// This function only tests target-independent requirements. -bool llvm::isInTailCallPosition(ImmutableCallSite CS, Attributes CalleeRetAttr, - const TargetLowering &TLI) { - const Instruction *I = CS.getInstruction(); - const BasicBlock *ExitBB = I->getParent(); - const TerminatorInst *Term = ExitBB->getTerminator(); - const ReturnInst *Ret = dyn_cast<ReturnInst>(Term); - const Function *F = ExitBB->getParent(); - - // The block must end in a return statement or unreachable. - // - // FIXME: Decline tailcall if it's not guaranteed and if the block ends in - // an unreachable, for now. The way tailcall optimization is currently - // implemented means it will add an epilogue followed by a jump. That is - // not profitable. Also, if the callee is a special function (e.g. - // longjmp on x86), it can end up causing miscompilation that has not - // been fully understood. - if (!Ret && - (!GuaranteedTailCallOpt || !isa<UnreachableInst>(Term))) return false; - - // If I will have a chain, make sure no other instruction that will have a - // chain interposes between I and the return. - if (I->mayHaveSideEffects() || I->mayReadFromMemory() || - !I->isSafeToSpeculativelyExecute()) - for (BasicBlock::const_iterator BBI = prior(prior(ExitBB->end())); ; - --BBI) { - if (&*BBI == I) - break; - // Debug info intrinsics do not get in the way of tail call optimization. - if (isa<DbgInfoIntrinsic>(BBI)) - continue; - if (BBI->mayHaveSideEffects() || BBI->mayReadFromMemory() || - !BBI->isSafeToSpeculativelyExecute()) - return false; - } - - // If the block ends with a void return or unreachable, it doesn't matter - // what the call's return type is. - if (!Ret || Ret->getNumOperands() == 0) return true; - - // If the return value is undef, it doesn't matter what the call's - // return type is. - if (isa<UndefValue>(Ret->getOperand(0))) return true; - - // Conservatively require the attributes of the call to match those of - // the return. Ignore noalias because it doesn't affect the call sequence. - unsigned CallerRetAttr = F->getAttributes().getRetAttributes(); - if ((CalleeRetAttr ^ CallerRetAttr) & ~Attribute::NoAlias) - return false; - - // It's not safe to eliminate the sign / zero extension of the return value. - if ((CallerRetAttr & Attribute::ZExt) || (CallerRetAttr & Attribute::SExt)) - return false; - - // Otherwise, make sure the unmodified return value of I is the return value. - for (const Instruction *U = dyn_cast<Instruction>(Ret->getOperand(0)); ; - U = dyn_cast<Instruction>(U->getOperand(0))) { - if (!U) - return false; - if (!U->hasOneUse()) - return false; - if (U == I) - break; - // Check for a truly no-op truncate. - if (isa<TruncInst>(U) && - TLI.isTruncateFree(U->getOperand(0)->getType(), U->getType())) - continue; - // Check for a truly no-op bitcast. - if (isa<BitCastInst>(U) && - (U->getOperand(0)->getType() == U->getType() || - (U->getOperand(0)->getType()->isPointerTy() && - U->getType()->isPointerTy()))) - continue; - // Otherwise it's not a true no-op. - return false; - } - - return true; -} diff --git a/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.h b/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.h index 0d9af1a..333fe22 100644 --- a/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.h +++ b/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.h @@ -118,30 +118,6 @@ public: } }; -/// ComputeLinearIndex - Given an LLVM IR aggregate type and a sequence -/// of insertvalue or extractvalue indices that identify a member, return -/// the linearized index of the start of the member. -/// -unsigned ComputeLinearIndex(const TargetLowering &TLI, const Type *Ty, - const unsigned *Indices, - const unsigned *IndicesEnd, - unsigned CurIndex = 0); - -/// ComputeValueVTs - Given an LLVM IR type, compute a sequence of -/// EVTs that represent all the individual underlying -/// non-aggregate types that comprise it. -/// -/// If Offsets is non-null, it points to a vector to be filled in -/// with the in-memory offsets of each of the individual values. -/// -void ComputeValueVTs(const TargetLowering &TLI, const Type *Ty, - SmallVectorImpl<EVT> &ValueVTs, - SmallVectorImpl<uint64_t> *Offsets = 0, - uint64_t StartingOffset = 0); - -/// ExtractTypeInfo - Returns the type info, possibly bitcast, encoded in V. -GlobalVariable *ExtractTypeInfo(Value *V); - /// AddCatchInfo - Extract the personality and type infos from an eh.selector /// call, and add them to the specified machine basic block. void AddCatchInfo(const CallInst &I, @@ -151,31 +127,6 @@ void AddCatchInfo(const CallInst &I, void CopyCatchInfo(const BasicBlock *SrcBB, const BasicBlock *DestBB, MachineModuleInfo *MMI, FunctionLoweringInfo &FLI); -/// hasInlineAsmMemConstraint - Return true if the inline asm instruction being -/// processed uses a memory 'm' constraint. -bool hasInlineAsmMemConstraint(std::vector<InlineAsm::ConstraintInfo> &CInfos, - const TargetLowering &TLI); - -/// getFCmpCondCode - Return the ISD condition code corresponding to -/// the given LLVM IR floating-point condition code. This includes -/// consideration of global floating-point math flags. -/// -ISD::CondCode getFCmpCondCode(FCmpInst::Predicate Pred); - -/// getICmpCondCode - Return the ISD condition code corresponding to -/// the given LLVM IR integer condition code. -/// -ISD::CondCode getICmpCondCode(ICmpInst::Predicate Pred); - -/// Test if the given instruction is in a position to be optimized -/// with a tail-call. This roughly means that it's in a block with -/// a return and there's nothing that needs to be scheduled -/// between it and the return. -/// -/// This function only tests target-independent requirements. -bool isInTailCallPosition(ImmutableCallSite CS, Attributes CalleeRetAttr, - const TargetLowering &TLI); - } // end namespace llvm #endif diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp index ce5a65b..b64ab49 100644 --- a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp +++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp @@ -30,6 +30,7 @@ #include "llvm/IntrinsicInst.h" #include "llvm/LLVMContext.h" #include "llvm/Module.h" +#include "llvm/CodeGen/Analysis.h" #include "llvm/CodeGen/FastISel.h" #include "llvm/CodeGen/GCStrategy.h" #include "llvm/CodeGen/GCMetadata.h" |