llvm-project/llvm/lib/IR/Instruction.cpp

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//===-- Instruction.cpp - Implement the Instruction class -----------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
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//
// This file implements the Instruction class for the IR library.
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//
//===----------------------------------------------------------------------===//
#include "llvm/IR/Instruction.h"
#include "llvm/IR/CallSite.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Operator.h"
#include "llvm/IR/Type.h"
using namespace llvm;
Instruction::Instruction(Type *ty, unsigned it, Use *Ops, unsigned NumOps,
Instruction *InsertBefore)
: User(ty, Value::InstructionVal + it, Ops, NumOps), Parent(nullptr) {
// If requested, insert this instruction into a basic block...
if (InsertBefore) {
BasicBlock *BB = InsertBefore->getParent();
assert(BB && "Instruction to insert before is not in a basic block!");
BB->getInstList().insert(InsertBefore->getIterator(), this);
}
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}
Instruction::Instruction(Type *ty, unsigned it, Use *Ops, unsigned NumOps,
BasicBlock *InsertAtEnd)
: User(ty, Value::InstructionVal + it, Ops, NumOps), Parent(nullptr) {
// append this instruction into the basic block
assert(InsertAtEnd && "Basic block to append to may not be NULL!");
InsertAtEnd->getInstList().push_back(this);
}
// Out of line virtual method, so the vtable, etc has a home.
Instruction::~Instruction() {
assert(!Parent && "Instruction still linked in the program!");
if (hasMetadataHashEntry())
clearMetadataHashEntries();
}
void Instruction::setParent(BasicBlock *P) {
Parent = P;
}
const Module *Instruction::getModule() const {
return getParent()->getModule();
}
Module *Instruction::getModule() {
return getParent()->getModule();
}
Function *Instruction::getFunction() { return getParent()->getParent(); }
const Function *Instruction::getFunction() const {
return getParent()->getParent();
}
void Instruction::removeFromParent() {
getParent()->getInstList().remove(getIterator());
}
iplist<Instruction>::iterator Instruction::eraseFromParent() {
return getParent()->getInstList().erase(getIterator());
}
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/// Insert an unlinked instruction into a basic block immediately before the
/// specified instruction.
void Instruction::insertBefore(Instruction *InsertPos) {
InsertPos->getParent()->getInstList().insert(InsertPos->getIterator(), this);
}
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/// Insert an unlinked instruction into a basic block immediately after the
/// specified instruction.
void Instruction::insertAfter(Instruction *InsertPos) {
InsertPos->getParent()->getInstList().insertAfter(InsertPos->getIterator(),
this);
}
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/// Unlink this instruction from its current basic block and insert it into the
/// basic block that MovePos lives in, right before MovePos.
void Instruction::moveBefore(Instruction *MovePos) {
MovePos->getParent()->getInstList().splice(
MovePos->getIterator(), getParent()->getInstList(), getIterator());
}
void Instruction::setHasNoUnsignedWrap(bool b) {
cast<OverflowingBinaryOperator>(this)->setHasNoUnsignedWrap(b);
}
void Instruction::setHasNoSignedWrap(bool b) {
cast<OverflowingBinaryOperator>(this)->setHasNoSignedWrap(b);
}
void Instruction::setIsExact(bool b) {
cast<PossiblyExactOperator>(this)->setIsExact(b);
}
bool Instruction::hasNoUnsignedWrap() const {
return cast<OverflowingBinaryOperator>(this)->hasNoUnsignedWrap();
}
bool Instruction::hasNoSignedWrap() const {
return cast<OverflowingBinaryOperator>(this)->hasNoSignedWrap();
}
bool Instruction::isExact() const {
return cast<PossiblyExactOperator>(this)->isExact();
}
/// Set or clear the unsafe-algebra flag on this instruction, which must be an
/// operator which supports this flag. See LangRef.html for the meaning of this
/// flag.
void Instruction::setHasUnsafeAlgebra(bool B) {
assert(isa<FPMathOperator>(this) && "setting fast-math flag on invalid op");
cast<FPMathOperator>(this)->setHasUnsafeAlgebra(B);
}
/// Set or clear the NoNaNs flag on this instruction, which must be an operator
/// which supports this flag. See LangRef.html for the meaning of this flag.
void Instruction::setHasNoNaNs(bool B) {
assert(isa<FPMathOperator>(this) && "setting fast-math flag on invalid op");
cast<FPMathOperator>(this)->setHasNoNaNs(B);
}
/// Set or clear the no-infs flag on this instruction, which must be an operator
/// which supports this flag. See LangRef.html for the meaning of this flag.
void Instruction::setHasNoInfs(bool B) {
assert(isa<FPMathOperator>(this) && "setting fast-math flag on invalid op");
cast<FPMathOperator>(this)->setHasNoInfs(B);
}
/// Set or clear the no-signed-zeros flag on this instruction, which must be an
/// operator which supports this flag. See LangRef.html for the meaning of this
/// flag.
void Instruction::setHasNoSignedZeros(bool B) {
assert(isa<FPMathOperator>(this) && "setting fast-math flag on invalid op");
cast<FPMathOperator>(this)->setHasNoSignedZeros(B);
}
/// Set or clear the allow-reciprocal flag on this instruction, which must be an
/// operator which supports this flag. See LangRef.html for the meaning of this
/// flag.
void Instruction::setHasAllowReciprocal(bool B) {
assert(isa<FPMathOperator>(this) && "setting fast-math flag on invalid op");
cast<FPMathOperator>(this)->setHasAllowReciprocal(B);
}
/// Convenience function for setting all the fast-math flags on this
/// instruction, which must be an operator which supports these flags. See
/// LangRef.html for the meaning of these flats.
void Instruction::setFastMathFlags(FastMathFlags FMF) {
assert(isa<FPMathOperator>(this) && "setting fast-math flag on invalid op");
cast<FPMathOperator>(this)->setFastMathFlags(FMF);
}
void Instruction::copyFastMathFlags(FastMathFlags FMF) {
assert(isa<FPMathOperator>(this) && "copying fast-math flag on invalid op");
cast<FPMathOperator>(this)->copyFastMathFlags(FMF);
}
/// Determine whether the unsafe-algebra flag is set.
bool Instruction::hasUnsafeAlgebra() const {
assert(isa<FPMathOperator>(this) && "getting fast-math flag on invalid op");
return cast<FPMathOperator>(this)->hasUnsafeAlgebra();
}
/// Determine whether the no-NaNs flag is set.
bool Instruction::hasNoNaNs() const {
assert(isa<FPMathOperator>(this) && "getting fast-math flag on invalid op");
return cast<FPMathOperator>(this)->hasNoNaNs();
}
/// Determine whether the no-infs flag is set.
bool Instruction::hasNoInfs() const {
assert(isa<FPMathOperator>(this) && "getting fast-math flag on invalid op");
return cast<FPMathOperator>(this)->hasNoInfs();
}
/// Determine whether the no-signed-zeros flag is set.
bool Instruction::hasNoSignedZeros() const {
assert(isa<FPMathOperator>(this) && "getting fast-math flag on invalid op");
return cast<FPMathOperator>(this)->hasNoSignedZeros();
}
/// Determine whether the allow-reciprocal flag is set.
bool Instruction::hasAllowReciprocal() const {
assert(isa<FPMathOperator>(this) && "getting fast-math flag on invalid op");
return cast<FPMathOperator>(this)->hasAllowReciprocal();
}
/// Convenience function for getting all the fast-math flags, which must be an
/// operator which supports these flags. See LangRef.html for the meaning of
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/// these flags.
FastMathFlags Instruction::getFastMathFlags() const {
assert(isa<FPMathOperator>(this) && "getting fast-math flag on invalid op");
return cast<FPMathOperator>(this)->getFastMathFlags();
}
/// Copy I's fast-math flags
void Instruction::copyFastMathFlags(const Instruction *I) {
copyFastMathFlags(I->getFastMathFlags());
}
void Instruction::copyIRFlags(const Value *V) {
// Copy the wrapping flags.
if (auto *OB = dyn_cast<OverflowingBinaryOperator>(V)) {
if (isa<OverflowingBinaryOperator>(this)) {
setHasNoSignedWrap(OB->hasNoSignedWrap());
setHasNoUnsignedWrap(OB->hasNoUnsignedWrap());
}
}
// Copy the exact flag.
if (auto *PE = dyn_cast<PossiblyExactOperator>(V))
if (isa<PossiblyExactOperator>(this))
setIsExact(PE->isExact());
// Copy the fast-math flags.
if (auto *FP = dyn_cast<FPMathOperator>(V))
if (isa<FPMathOperator>(this))
copyFastMathFlags(FP->getFastMathFlags());
if (auto *SrcGEP = dyn_cast<GetElementPtrInst>(V))
if (auto *DestGEP = dyn_cast<GetElementPtrInst>(this))
DestGEP->setIsInBounds(SrcGEP->isInBounds() | DestGEP->isInBounds());
}
void Instruction::andIRFlags(const Value *V) {
if (auto *OB = dyn_cast<OverflowingBinaryOperator>(V)) {
if (isa<OverflowingBinaryOperator>(this)) {
setHasNoSignedWrap(hasNoSignedWrap() & OB->hasNoSignedWrap());
setHasNoUnsignedWrap(hasNoUnsignedWrap() & OB->hasNoUnsignedWrap());
}
}
if (auto *PE = dyn_cast<PossiblyExactOperator>(V))
if (isa<PossiblyExactOperator>(this))
setIsExact(isExact() & PE->isExact());
if (auto *FP = dyn_cast<FPMathOperator>(V)) {
if (isa<FPMathOperator>(this)) {
FastMathFlags FM = getFastMathFlags();
FM &= FP->getFastMathFlags();
copyFastMathFlags(FM);
}
}
if (auto *SrcGEP = dyn_cast<GetElementPtrInst>(V))
if (auto *DestGEP = dyn_cast<GetElementPtrInst>(this))
DestGEP->setIsInBounds(SrcGEP->isInBounds() & DestGEP->isInBounds());
}
const char *Instruction::getOpcodeName(unsigned OpCode) {
switch (OpCode) {
// Terminators
case Ret: return "ret";
case Br: return "br";
case Switch: return "switch";
case IndirectBr: return "indirectbr";
case Invoke: return "invoke";
case Resume: return "resume";
case Unreachable: return "unreachable";
case CleanupRet: return "cleanupret";
case CatchRet: return "catchret";
case CatchPad: return "catchpad";
[IR] Reformulate LLVM's EH funclet IR While we have successfully implemented a funclet-oriented EH scheme on top of LLVM IR, our scheme has some notable deficiencies: - catchendpad and cleanupendpad are necessary in the current design but they are difficult to explain to others, even to seasoned LLVM experts. - catchendpad and cleanupendpad are optimization barriers. They cannot be split and force all potentially throwing call-sites to be invokes. This has a noticable effect on the quality of our code generation. - catchpad, while similar in some aspects to invoke, is fairly awkward. It is unsplittable, starts a funclet, and has control flow to other funclets. - The nesting relationship between funclets is currently a property of control flow edges. Because of this, we are forced to carefully analyze the flow graph to see if there might potentially exist illegal nesting among funclets. While we have logic to clone funclets when they are illegally nested, it would be nicer if we had a representation which forbade them upfront. Let's clean this up a bit by doing the following: - Instead, make catchpad more like cleanuppad and landingpad: no control flow, just a bunch of simple operands; catchpad would be splittable. - Introduce catchswitch, a control flow instruction designed to model the constraints of funclet oriented EH. - Make funclet scoping explicit by having funclet instructions consume the token produced by the funclet which contains them. - Remove catchendpad and cleanupendpad. Their presence can be inferred implicitly using coloring information. N.B. The state numbering code for the CLR has been updated but the veracity of it's output cannot be spoken for. An expert should take a look to make sure the results are reasonable. Reviewers: rnk, JosephTremoulet, andrew.w.kaylor Differential Revision: http://reviews.llvm.org/D15139 llvm-svn: 255422
2015-12-12 13:38:55 +08:00
case CatchSwitch: return "catchswitch";
// Standard binary operators...
case Add: return "add";
case FAdd: return "fadd";
case Sub: return "sub";
case FSub: return "fsub";
case Mul: return "mul";
case FMul: return "fmul";
case UDiv: return "udiv";
case SDiv: return "sdiv";
case FDiv: return "fdiv";
case URem: return "urem";
case SRem: return "srem";
case FRem: return "frem";
// Logical operators...
case And: return "and";
case Or : return "or";
case Xor: return "xor";
// Memory instructions...
case Alloca: return "alloca";
case Load: return "load";
case Store: return "store";
case AtomicCmpXchg: return "cmpxchg";
case AtomicRMW: return "atomicrmw";
case Fence: return "fence";
case GetElementPtr: return "getelementptr";
// Convert instructions...
case Trunc: return "trunc";
case ZExt: return "zext";
case SExt: return "sext";
case FPTrunc: return "fptrunc";
case FPExt: return "fpext";
case FPToUI: return "fptoui";
case FPToSI: return "fptosi";
case UIToFP: return "uitofp";
case SIToFP: return "sitofp";
case IntToPtr: return "inttoptr";
case PtrToInt: return "ptrtoint";
case BitCast: return "bitcast";
case AddrSpaceCast: return "addrspacecast";
// Other instructions...
case ICmp: return "icmp";
case FCmp: return "fcmp";
case PHI: return "phi";
case Select: return "select";
case Call: return "call";
case Shl: return "shl";
case LShr: return "lshr";
case AShr: return "ashr";
case VAArg: return "va_arg";
case ExtractElement: return "extractelement";
case InsertElement: return "insertelement";
case ShuffleVector: return "shufflevector";
case ExtractValue: return "extractvalue";
case InsertValue: return "insertvalue";
case LandingPad: return "landingpad";
case CleanupPad: return "cleanuppad";
default: return "<Invalid operator> ";
}
}
/// Return true if both instructions have the same special state This must be
/// kept in sync with FunctionComparator::cmpOperations in
/// lib/Transforms/IPO/MergeFunctions.cpp.
static bool haveSameSpecialState(const Instruction *I1, const Instruction *I2,
bool IgnoreAlignment = false) {
assert(I1->getOpcode() == I2->getOpcode() &&
"Can not compare special state of different instructions");
if (const AllocaInst *AI = dyn_cast<AllocaInst>(I1))
return AI->getAllocatedType() == cast<AllocaInst>(I2)->getAllocatedType() &&
(AI->getAlignment() == cast<AllocaInst>(I2)->getAlignment() ||
IgnoreAlignment);
if (const LoadInst *LI = dyn_cast<LoadInst>(I1))
return LI->isVolatile() == cast<LoadInst>(I2)->isVolatile() &&
(LI->getAlignment() == cast<LoadInst>(I2)->getAlignment() ||
IgnoreAlignment) &&
LI->getOrdering() == cast<LoadInst>(I2)->getOrdering() &&
LI->getSynchScope() == cast<LoadInst>(I2)->getSynchScope();
if (const StoreInst *SI = dyn_cast<StoreInst>(I1))
return SI->isVolatile() == cast<StoreInst>(I2)->isVolatile() &&
(SI->getAlignment() == cast<StoreInst>(I2)->getAlignment() ||
IgnoreAlignment) &&
SI->getOrdering() == cast<StoreInst>(I2)->getOrdering() &&
SI->getSynchScope() == cast<StoreInst>(I2)->getSynchScope();
if (const CmpInst *CI = dyn_cast<CmpInst>(I1))
return CI->getPredicate() == cast<CmpInst>(I2)->getPredicate();
if (const CallInst *CI = dyn_cast<CallInst>(I1))
return CI->isTailCall() == cast<CallInst>(I2)->isTailCall() &&
CI->getCallingConv() == cast<CallInst>(I2)->getCallingConv() &&
CI->getAttributes() == cast<CallInst>(I2)->getAttributes() &&
CI->hasIdenticalOperandBundleSchema(*cast<CallInst>(I2));
if (const InvokeInst *CI = dyn_cast<InvokeInst>(I1))
return CI->getCallingConv() == cast<InvokeInst>(I2)->getCallingConv() &&
CI->getAttributes() == cast<InvokeInst>(I2)->getAttributes() &&
CI->hasIdenticalOperandBundleSchema(*cast<InvokeInst>(I2));
if (const InsertValueInst *IVI = dyn_cast<InsertValueInst>(I1))
return IVI->getIndices() == cast<InsertValueInst>(I2)->getIndices();
if (const ExtractValueInst *EVI = dyn_cast<ExtractValueInst>(I1))
return EVI->getIndices() == cast<ExtractValueInst>(I2)->getIndices();
if (const FenceInst *FI = dyn_cast<FenceInst>(I1))
return FI->getOrdering() == cast<FenceInst>(I2)->getOrdering() &&
FI->getSynchScope() == cast<FenceInst>(I2)->getSynchScope();
if (const AtomicCmpXchgInst *CXI = dyn_cast<AtomicCmpXchgInst>(I1))
return CXI->isVolatile() == cast<AtomicCmpXchgInst>(I2)->isVolatile() &&
CXI->isWeak() == cast<AtomicCmpXchgInst>(I2)->isWeak() &&
CXI->getSuccessOrdering() ==
cast<AtomicCmpXchgInst>(I2)->getSuccessOrdering() &&
CXI->getFailureOrdering() ==
cast<AtomicCmpXchgInst>(I2)->getFailureOrdering() &&
CXI->getSynchScope() == cast<AtomicCmpXchgInst>(I2)->getSynchScope();
if (const AtomicRMWInst *RMWI = dyn_cast<AtomicRMWInst>(I1))
return RMWI->getOperation() == cast<AtomicRMWInst>(I2)->getOperation() &&
RMWI->isVolatile() == cast<AtomicRMWInst>(I2)->isVolatile() &&
RMWI->getOrdering() == cast<AtomicRMWInst>(I2)->getOrdering() &&
RMWI->getSynchScope() == cast<AtomicRMWInst>(I2)->getSynchScope();
return true;
}
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/// isIdenticalTo - Return true if the specified instruction is exactly
/// identical to the current one. This means that all operands match and any
/// extra information (e.g. load is volatile) agree.
bool Instruction::isIdenticalTo(const Instruction *I) const {
return isIdenticalToWhenDefined(I) &&
SubclassOptionalData == I->SubclassOptionalData;
}
/// isIdenticalToWhenDefined - This is like isIdenticalTo, except that it
/// ignores the SubclassOptionalData flags, which specify conditions
/// under which the instruction's result is undefined.
bool Instruction::isIdenticalToWhenDefined(const Instruction *I) const {
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if (getOpcode() != I->getOpcode() ||
getNumOperands() != I->getNumOperands() ||
getType() != I->getType())
return false;
// If both instructions have no operands, they are identical.
if (getNumOperands() == 0 && I->getNumOperands() == 0)
return haveSameSpecialState(this, I);
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// We have two instructions of identical opcode and #operands. Check to see
// if all operands are the same.
if (!std::equal(op_begin(), op_end(), I->op_begin()))
return false;
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if (const PHINode *thisPHI = dyn_cast<PHINode>(this)) {
const PHINode *otherPHI = cast<PHINode>(I);
return std::equal(thisPHI->block_begin(), thisPHI->block_end(),
otherPHI->block_begin());
}
return haveSameSpecialState(this, I);
}
// Keep this in sync with FunctionComparator::cmpOperations in
// lib/Transforms/IPO/MergeFunctions.cpp.
bool Instruction::isSameOperationAs(const Instruction *I,
unsigned flags) const {
bool IgnoreAlignment = flags & CompareIgnoringAlignment;
bool UseScalarTypes = flags & CompareUsingScalarTypes;
if (getOpcode() != I->getOpcode() ||
getNumOperands() != I->getNumOperands() ||
(UseScalarTypes ?
getType()->getScalarType() != I->getType()->getScalarType() :
getType() != I->getType()))
return false;
// We have two instructions of identical opcode and #operands. Check to see
// if all operands are the same type
for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
if (UseScalarTypes ?
getOperand(i)->getType()->getScalarType() !=
I->getOperand(i)->getType()->getScalarType() :
getOperand(i)->getType() != I->getOperand(i)->getType())
return false;
return haveSameSpecialState(this, I, IgnoreAlignment);
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}
/// isUsedOutsideOfBlock - Return true if there are any uses of I outside of the
/// specified block. Note that PHI nodes are considered to evaluate their
/// operands in the corresponding predecessor block.
bool Instruction::isUsedOutsideOfBlock(const BasicBlock *BB) const {
[C++11] Add range based accessors for the Use-Def chain of a Value. This requires a number of steps. 1) Move value_use_iterator into the Value class as an implementation detail 2) Change it to actually be a *Use* iterator rather than a *User* iterator. 3) Add an adaptor which is a User iterator that always looks through the Use to the User. 4) Wrap these in Value::use_iterator and Value::user_iterator typedefs. 5) Add the range adaptors as Value::uses() and Value::users(). 6) Update *all* of the callers to correctly distinguish between whether they wanted a use_iterator (and to explicitly dig out the User when needed), or a user_iterator which makes the Use itself totally opaque. Because #6 requires churning essentially everything that walked the Use-Def chains, I went ahead and added all of the range adaptors and switched them to range-based loops where appropriate. Also because the renaming requires at least churning every line of code, it didn't make any sense to split these up into multiple commits -- all of which would touch all of the same lies of code. The result is still not quite optimal. The Value::use_iterator is a nice regular iterator, but Value::user_iterator is an iterator over User*s rather than over the User objects themselves. As a consequence, it fits a bit awkwardly into the range-based world and it has the weird extra-dereferencing 'operator->' that so many of our iterators have. I think this could be fixed by providing something which transforms a range of T&s into a range of T*s, but that *can* be separated into another patch, and it isn't yet 100% clear whether this is the right move. However, this change gets us most of the benefit and cleans up a substantial amount of code around Use and User. =] llvm-svn: 203364
2014-03-09 11:16:01 +08:00
for (const Use &U : uses()) {
// PHI nodes uses values in the corresponding predecessor block. For other
// instructions, just check to see whether the parent of the use matches up.
[C++11] Add range based accessors for the Use-Def chain of a Value. This requires a number of steps. 1) Move value_use_iterator into the Value class as an implementation detail 2) Change it to actually be a *Use* iterator rather than a *User* iterator. 3) Add an adaptor which is a User iterator that always looks through the Use to the User. 4) Wrap these in Value::use_iterator and Value::user_iterator typedefs. 5) Add the range adaptors as Value::uses() and Value::users(). 6) Update *all* of the callers to correctly distinguish between whether they wanted a use_iterator (and to explicitly dig out the User when needed), or a user_iterator which makes the Use itself totally opaque. Because #6 requires churning essentially everything that walked the Use-Def chains, I went ahead and added all of the range adaptors and switched them to range-based loops where appropriate. Also because the renaming requires at least churning every line of code, it didn't make any sense to split these up into multiple commits -- all of which would touch all of the same lies of code. The result is still not quite optimal. The Value::use_iterator is a nice regular iterator, but Value::user_iterator is an iterator over User*s rather than over the User objects themselves. As a consequence, it fits a bit awkwardly into the range-based world and it has the weird extra-dereferencing 'operator->' that so many of our iterators have. I think this could be fixed by providing something which transforms a range of T&s into a range of T*s, but that *can* be separated into another patch, and it isn't yet 100% clear whether this is the right move. However, this change gets us most of the benefit and cleans up a substantial amount of code around Use and User. =] llvm-svn: 203364
2014-03-09 11:16:01 +08:00
const Instruction *I = cast<Instruction>(U.getUser());
const PHINode *PN = dyn_cast<PHINode>(I);
if (!PN) {
[C++11] Add range based accessors for the Use-Def chain of a Value. This requires a number of steps. 1) Move value_use_iterator into the Value class as an implementation detail 2) Change it to actually be a *Use* iterator rather than a *User* iterator. 3) Add an adaptor which is a User iterator that always looks through the Use to the User. 4) Wrap these in Value::use_iterator and Value::user_iterator typedefs. 5) Add the range adaptors as Value::uses() and Value::users(). 6) Update *all* of the callers to correctly distinguish between whether they wanted a use_iterator (and to explicitly dig out the User when needed), or a user_iterator which makes the Use itself totally opaque. Because #6 requires churning essentially everything that walked the Use-Def chains, I went ahead and added all of the range adaptors and switched them to range-based loops where appropriate. Also because the renaming requires at least churning every line of code, it didn't make any sense to split these up into multiple commits -- all of which would touch all of the same lies of code. The result is still not quite optimal. The Value::use_iterator is a nice regular iterator, but Value::user_iterator is an iterator over User*s rather than over the User objects themselves. As a consequence, it fits a bit awkwardly into the range-based world and it has the weird extra-dereferencing 'operator->' that so many of our iterators have. I think this could be fixed by providing something which transforms a range of T&s into a range of T*s, but that *can* be separated into another patch, and it isn't yet 100% clear whether this is the right move. However, this change gets us most of the benefit and cleans up a substantial amount of code around Use and User. =] llvm-svn: 203364
2014-03-09 11:16:01 +08:00
if (I->getParent() != BB)
return true;
continue;
}
[C++11] Add range based accessors for the Use-Def chain of a Value. This requires a number of steps. 1) Move value_use_iterator into the Value class as an implementation detail 2) Change it to actually be a *Use* iterator rather than a *User* iterator. 3) Add an adaptor which is a User iterator that always looks through the Use to the User. 4) Wrap these in Value::use_iterator and Value::user_iterator typedefs. 5) Add the range adaptors as Value::uses() and Value::users(). 6) Update *all* of the callers to correctly distinguish between whether they wanted a use_iterator (and to explicitly dig out the User when needed), or a user_iterator which makes the Use itself totally opaque. Because #6 requires churning essentially everything that walked the Use-Def chains, I went ahead and added all of the range adaptors and switched them to range-based loops where appropriate. Also because the renaming requires at least churning every line of code, it didn't make any sense to split these up into multiple commits -- all of which would touch all of the same lies of code. The result is still not quite optimal. The Value::use_iterator is a nice regular iterator, but Value::user_iterator is an iterator over User*s rather than over the User objects themselves. As a consequence, it fits a bit awkwardly into the range-based world and it has the weird extra-dereferencing 'operator->' that so many of our iterators have. I think this could be fixed by providing something which transforms a range of T&s into a range of T*s, but that *can* be separated into another patch, and it isn't yet 100% clear whether this is the right move. However, this change gets us most of the benefit and cleans up a substantial amount of code around Use and User. =] llvm-svn: 203364
2014-03-09 11:16:01 +08:00
if (PN->getIncomingBlock(U) != BB)
return true;
}
return false;
}
/// mayReadFromMemory - Return true if this instruction may read memory.
///
bool Instruction::mayReadFromMemory() const {
switch (getOpcode()) {
default: return false;
case Instruction::VAArg:
case Instruction::Load:
case Instruction::Fence: // FIXME: refine definition of mayReadFromMemory
case Instruction::AtomicCmpXchg:
case Instruction::AtomicRMW:
case Instruction::CatchPad:
case Instruction::CatchRet:
return true;
case Instruction::Call:
return !cast<CallInst>(this)->doesNotAccessMemory();
case Instruction::Invoke:
return !cast<InvokeInst>(this)->doesNotAccessMemory();
case Instruction::Store:
return !cast<StoreInst>(this)->isUnordered();
}
}
/// mayWriteToMemory - Return true if this instruction may modify memory.
///
bool Instruction::mayWriteToMemory() const {
switch (getOpcode()) {
default: return false;
case Instruction::Fence: // FIXME: refine definition of mayWriteToMemory
case Instruction::Store:
case Instruction::VAArg:
case Instruction::AtomicCmpXchg:
case Instruction::AtomicRMW:
case Instruction::CatchPad:
case Instruction::CatchRet:
return true;
case Instruction::Call:
return !cast<CallInst>(this)->onlyReadsMemory();
case Instruction::Invoke:
return !cast<InvokeInst>(this)->onlyReadsMemory();
case Instruction::Load:
return !cast<LoadInst>(this)->isUnordered();
}
}
bool Instruction::isAtomic() const {
switch (getOpcode()) {
default:
return false;
case Instruction::AtomicCmpXchg:
case Instruction::AtomicRMW:
case Instruction::Fence:
return true;
case Instruction::Load:
return cast<LoadInst>(this)->getOrdering() != AtomicOrdering::NotAtomic;
case Instruction::Store:
return cast<StoreInst>(this)->getOrdering() != AtomicOrdering::NotAtomic;
}
}
bool Instruction::mayThrow() const {
if (const CallInst *CI = dyn_cast<CallInst>(this))
return !CI->doesNotThrow();
if (const auto *CRI = dyn_cast<CleanupReturnInst>(this))
return CRI->unwindsToCaller();
[IR] Reformulate LLVM's EH funclet IR While we have successfully implemented a funclet-oriented EH scheme on top of LLVM IR, our scheme has some notable deficiencies: - catchendpad and cleanupendpad are necessary in the current design but they are difficult to explain to others, even to seasoned LLVM experts. - catchendpad and cleanupendpad are optimization barriers. They cannot be split and force all potentially throwing call-sites to be invokes. This has a noticable effect on the quality of our code generation. - catchpad, while similar in some aspects to invoke, is fairly awkward. It is unsplittable, starts a funclet, and has control flow to other funclets. - The nesting relationship between funclets is currently a property of control flow edges. Because of this, we are forced to carefully analyze the flow graph to see if there might potentially exist illegal nesting among funclets. While we have logic to clone funclets when they are illegally nested, it would be nicer if we had a representation which forbade them upfront. Let's clean this up a bit by doing the following: - Instead, make catchpad more like cleanuppad and landingpad: no control flow, just a bunch of simple operands; catchpad would be splittable. - Introduce catchswitch, a control flow instruction designed to model the constraints of funclet oriented EH. - Make funclet scoping explicit by having funclet instructions consume the token produced by the funclet which contains them. - Remove catchendpad and cleanupendpad. Their presence can be inferred implicitly using coloring information. N.B. The state numbering code for the CLR has been updated but the veracity of it's output cannot be spoken for. An expert should take a look to make sure the results are reasonable. Reviewers: rnk, JosephTremoulet, andrew.w.kaylor Differential Revision: http://reviews.llvm.org/D15139 llvm-svn: 255422
2015-12-12 13:38:55 +08:00
if (const auto *CatchSwitch = dyn_cast<CatchSwitchInst>(this))
return CatchSwitch->unwindsToCaller();
return isa<ResumeInst>(this);
}
/// isAssociative - Return true if the instruction is associative:
///
/// Associative operators satisfy: x op (y op z) === (x op y) op z
///
/// In LLVM, the Add, Mul, And, Or, and Xor operators are associative.
///
bool Instruction::isAssociative(unsigned Opcode) {
return Opcode == And || Opcode == Or || Opcode == Xor ||
Opcode == Add || Opcode == Mul;
}
bool Instruction::isAssociative() const {
unsigned Opcode = getOpcode();
if (isAssociative(Opcode))
return true;
switch (Opcode) {
case FMul:
case FAdd:
return cast<FPMathOperator>(this)->hasUnsafeAlgebra();
default:
return false;
}
}
/// isCommutative - Return true if the instruction is commutative:
///
2003-10-11 01:54:14 +08:00
/// Commutative operators satisfy: (x op y) === (y op x)
///
/// In LLVM, these are the associative operators, plus SetEQ and SetNE, when
/// applied to any type.
///
bool Instruction::isCommutative(unsigned op) {
switch (op) {
case Add:
case FAdd:
case Mul:
case FMul:
case And:
case Or:
case Xor:
return true;
default:
return false;
}
}
/// isIdempotent - Return true if the instruction is idempotent:
///
/// Idempotent operators satisfy: x op x === x
///
/// In LLVM, the And and Or operators are idempotent.
///
bool Instruction::isIdempotent(unsigned Opcode) {
return Opcode == And || Opcode == Or;
}
/// isNilpotent - Return true if the instruction is nilpotent:
///
/// Nilpotent operators satisfy: x op x === Id,
///
/// where Id is the identity for the operator, i.e. a constant such that
/// x op Id === x and Id op x === x for all x.
///
/// In LLVM, the Xor operator is nilpotent.
///
bool Instruction::isNilpotent(unsigned Opcode) {
return Opcode == Xor;
}
Instruction *Instruction::cloneImpl() const {
llvm_unreachable("Subclass of Instruction failed to implement cloneImpl");
}
Instruction *Instruction::clone() const {
Instruction *New = nullptr;
switch (getOpcode()) {
default:
llvm_unreachable("Unhandled Opcode.");
#define HANDLE_INST(num, opc, clas) \
case Instruction::opc: \
New = cast<clas>(this)->cloneImpl(); \
break;
#include "llvm/IR/Instruction.def"
#undef HANDLE_INST
}
New->SubclassOptionalData = SubclassOptionalData;
if (!hasMetadata())
return New;
// Otherwise, enumerate and copy over metadata from the old instruction to the
// new one.
SmallVector<std::pair<unsigned, MDNode *>, 4> TheMDs;
getAllMetadataOtherThanDebugLoc(TheMDs);
for (const auto &MD : TheMDs)
New->setMetadata(MD.first, MD.second);
New->setDebugLoc(getDebugLoc());
return New;
}