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

724 lines
26 KiB
C++

//===- Instruction.cpp - MLIR Instruction Classes -------------------------===//
//
// Copyright 2019 The MLIR Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// =============================================================================
#include "AttributeListStorage.h"
#include "mlir/IR/AffineExpr.h"
#include "mlir/IR/AffineMap.h"
#include "mlir/IR/BlockAndValueMapping.h"
#include "mlir/IR/BuiltinOps.h"
#include "mlir/IR/Function.h"
#include "mlir/IR/InstVisitor.h"
#include "mlir/IR/Instructions.h"
#include "mlir/IR/IntegerSet.h"
#include "mlir/IR/MLIRContext.h"
#include "llvm/ADT/DenseMap.h"
using namespace mlir;
//===----------------------------------------------------------------------===//
// InstResult
//===----------------------------------------------------------------------===//
/// Return the result number of this result.
unsigned InstResult::getResultNumber() const {
// Results are always stored consecutively, so use pointer subtraction to
// figure out what number this is.
return this - &getOwner()->getInstResults()[0];
}
//===----------------------------------------------------------------------===//
// InstOperand
//===----------------------------------------------------------------------===//
/// Return which operand this is in the operand list.
template <> unsigned InstOperand::getOperandNumber() const {
return this - &getOwner()->getInstOperands()[0];
}
/// Return which operand this is in the operand list.
template <> unsigned BlockOperand::getOperandNumber() const {
return this - &getOwner()->getBlockOperands()[0];
}
//===----------------------------------------------------------------------===//
// OperandStorage
//===----------------------------------------------------------------------===//
/// Replace the operands contained in the storage with the ones provided in
/// 'operands'.
void detail::OperandStorage::setOperands(Instruction *owner,
ArrayRef<Value *> operands) {
// If the number of operands is less than or equal to the current amount, we
// can just update in place.
if (operands.size() <= numOperands) {
auto instOperands = getInstOperands();
// If the number of new operands is less than the current count, then remove
// any extra operands.
for (unsigned i = operands.size(); i != numOperands; ++i)
instOperands[i].~InstOperand();
// Set the operands in place.
numOperands = operands.size();
for (unsigned i = 0; i != numOperands; ++i)
instOperands[i].set(operands[i]);
return;
}
// Otherwise, we need to be resizable.
assert(resizable && "Only resizable operations may add operands");
// Grow the capacity if necessary.
auto &resizeUtil = getResizableStorage();
if (resizeUtil.capacity < operands.size())
grow(resizeUtil, operands.size());
// Set the operands.
InstOperand *opBegin = getRawOperands();
for (unsigned i = 0; i != numOperands; ++i)
opBegin[i].set(operands[i]);
for (unsigned e = operands.size(); numOperands != e; ++numOperands)
new (&opBegin[numOperands]) InstOperand(owner, operands[numOperands]);
}
/// Erase an operand held by the storage.
void detail::OperandStorage::eraseOperand(unsigned index) {
assert(index < size());
auto Operands = getInstOperands();
--numOperands;
// Shift all operands down by 1 if the operand to remove is not at the end.
if (index != numOperands)
std::rotate(&Operands[index], &Operands[index + 1], &Operands[numOperands]);
Operands[numOperands].~InstOperand();
}
/// Grow the internal operand storage.
void detail::OperandStorage::grow(ResizableStorage &resizeUtil,
size_t minSize) {
// Allocate a new storage array.
resizeUtil.capacity =
std::max(size_t(llvm::NextPowerOf2(resizeUtil.capacity + 2)), minSize);
InstOperand *newStorage = static_cast<InstOperand *>(
llvm::safe_malloc(resizeUtil.capacity * sizeof(InstOperand)));
// Move the current operands to the new storage.
auto operands = getInstOperands();
std::uninitialized_copy(std::make_move_iterator(operands.begin()),
std::make_move_iterator(operands.end()), newStorage);
// Destroy the original operands and update the resizable storage pointer.
for (auto &operand : operands)
operand.~InstOperand();
resizeUtil.setDynamicStorage(newStorage);
}
//===----------------------------------------------------------------------===//
// Instruction
//===----------------------------------------------------------------------===//
// Instructions are deleted through the destroy() member because we don't have
// a virtual destructor.
Instruction::~Instruction() {
assert(block == nullptr && "instruction destroyed but still in a block");
}
/// Destroy this instruction or one of its subclasses.
void Instruction::destroy() {
switch (this->getKind()) {
case Kind::OperationInst:
cast<OperationInst>(this)->destroy();
break;
}
}
/// Return the context this operation is associated with.
MLIRContext *Instruction::getContext() const {
return cast<OperationInst>(this)->getContext();
}
Instruction *Instruction::getParentInst() const {
return block ? block->getContainingInst() : nullptr;
}
Function *Instruction::getFunction() const {
return block ? block->getFunction() : nullptr;
}
Value *Instruction::getOperand(unsigned idx) {
return getInstOperand(idx).get();
}
const Value *Instruction::getOperand(unsigned idx) const {
return getInstOperand(idx).get();
}
// Value can be used as a dimension id if it is valid as a symbol, or
// it is an induction variable, or it is a result of affine apply operation
// with dimension id arguments.
bool Value::isValidDim() const {
if (auto *inst = getDefiningInst()) {
// Top level instruction or constant operation is ok.
if (inst->getParentInst() == nullptr || inst->isa<ConstantOp>())
return true;
// Affine apply operation is ok if all of its operands are ok.
if (auto op = inst->dyn_cast<AffineApplyOp>())
return op->isValidDim();
return false;
}
// This value is either a function argument or an induction variable. Both
// are ok.
return true;
}
// Value can be used as a symbol if it is a constant, or it is defined at
// the top level, or it is a result of affine apply operation with symbol
// arguments.
bool Value::isValidSymbol() const {
if (auto *inst = getDefiningInst()) {
// Top level instruction or constant operation is ok.
if (inst->getParentInst() == nullptr || inst->isa<ConstantOp>())
return true;
// Affine apply operation is ok if all of its operands are ok.
if (auto op = inst->dyn_cast<AffineApplyOp>())
return op->isValidSymbol();
return false;
}
// Otherwise, the only valid symbol is a function argument.
auto *arg = dyn_cast<BlockArgument>(this);
return arg && arg->isFunctionArgument();
}
void Instruction::setOperand(unsigned idx, Value *value) {
getInstOperand(idx).set(value);
}
unsigned Instruction::getNumOperands() const {
switch (getKind()) {
case Kind::OperationInst:
return cast<OperationInst>(this)->getNumOperands();
}
}
MutableArrayRef<InstOperand> Instruction::getInstOperands() {
switch (getKind()) {
case Kind::OperationInst:
return cast<OperationInst>(this)->getInstOperands();
}
}
/// Emit a note about this instruction, reporting up to any diagnostic
/// handlers that may be listening.
void Instruction::emitNote(const Twine &message) const {
getContext()->emitDiagnostic(getLoc(), message,
MLIRContext::DiagnosticKind::Note);
}
/// Emit a warning about this instruction, reporting up to any diagnostic
/// handlers that may be listening.
void Instruction::emitWarning(const Twine &message) const {
getContext()->emitDiagnostic(getLoc(), message,
MLIRContext::DiagnosticKind::Warning);
}
/// Emit an error about fatal conditions with this operation, reporting up to
/// any diagnostic handlers that may be listening. This function always
/// returns true. NOTE: This may terminate the containing application, only
/// use when the IR is in an inconsistent state.
bool Instruction::emitError(const Twine &message) const {
return getContext()->emitError(getLoc(), message);
}
/// Given an instruction 'other' that is within the same parent block, return
/// whether the current instruction is before 'other' in the instruction list
/// of the parent block.
/// Note: This function has an average complexity of O(1), but worst case may
/// take O(N) where N is the number of instructions within the parent block.
bool Instruction::isBeforeInBlock(const Instruction *other) const {
assert(block && "Instructions without parent blocks have no order.");
assert(other && other->block == block &&
"Expected other instruction to have the same parent block.");
// Recompute the parent ordering if necessary.
if (!block->isInstOrderValid())
block->recomputeInstOrder();
return orderIndex < other->orderIndex;
}
/// Returns whether the Instruction is a terminator.
bool Instruction::isTerminator() const {
if (auto *op = dyn_cast<OperationInst>(this))
return op->isTerminator();
return false;
}
//===----------------------------------------------------------------------===//
// ilist_traits for Instruction
//===----------------------------------------------------------------------===//
void llvm::ilist_traits<::mlir::Instruction>::deleteNode(Instruction *inst) {
inst->destroy();
}
Block *llvm::ilist_traits<::mlir::Instruction>::getContainingBlock() {
size_t Offset(size_t(&((Block *)nullptr->*Block::getSublistAccess(nullptr))));
iplist<Instruction> *Anchor(static_cast<iplist<Instruction> *>(this));
return reinterpret_cast<Block *>(reinterpret_cast<char *>(Anchor) - Offset);
}
/// This is a trait method invoked when a instruction is added to a block. We
/// keep the block pointer up to date.
void llvm::ilist_traits<::mlir::Instruction>::addNodeToList(Instruction *inst) {
assert(!inst->getBlock() && "already in a instruction block!");
inst->block = getContainingBlock();
// Invalidate the block ordering.
inst->block->invalidateInstOrder();
}
/// This is a trait method invoked when a instruction is removed from a block.
/// We keep the block pointer up to date.
void llvm::ilist_traits<::mlir::Instruction>::removeNodeFromList(
Instruction *inst) {
assert(inst->block && "not already in a instruction block!");
inst->block = nullptr;
}
/// This is a trait method invoked when a instruction is moved from one block
/// to another. We keep the block pointer up to date.
void llvm::ilist_traits<::mlir::Instruction>::transferNodesFromList(
ilist_traits<Instruction> &otherList, inst_iterator first,
inst_iterator last) {
Block *curParent = getContainingBlock();
// Invalidate the ordering of the parent block.
curParent->invalidateInstOrder();
// If we are transferring instructions within the same block, the block
// pointer doesn't need to be updated.
if (curParent == otherList.getContainingBlock())
return;
// Update the 'block' member of each instruction.
for (; first != last; ++first)
first->block = curParent;
}
/// Remove this instruction (and its descendants) from its Block and delete
/// all of them.
void Instruction::erase() {
assert(getBlock() && "Instruction has no block");
getBlock()->getInstructions().erase(this);
}
/// Unlink this instruction from its current block and insert it right before
/// `existingInst` which may be in the same or another block in the same
/// function.
void Instruction::moveBefore(Instruction *existingInst) {
moveBefore(existingInst->getBlock(), existingInst->getIterator());
}
/// Unlink this operation instruction from its current basic block and insert
/// it right before `iterator` in the specified basic block.
void Instruction::moveBefore(Block *block,
llvm::iplist<Instruction>::iterator iterator) {
block->getInstructions().splice(iterator, getBlock()->getInstructions(),
getIterator());
}
/// This drops all operand uses from this instruction, which is an essential
/// step in breaking cyclic dependences between references when they are to
/// be deleted.
void Instruction::dropAllReferences() {
for (auto &op : getInstOperands())
op.drop();
switch (getKind()) {
case Kind::OperationInst: {
auto *opInst = cast<OperationInst>(this);
if (isTerminator())
for (auto &dest : opInst->getBlockOperands())
dest.drop();
for (auto &blockList : opInst->getBlockLists())
for (Block &block : blockList)
block.dropAllReferences();
break;
}
}
}
//===----------------------------------------------------------------------===//
// OperationInst
//===----------------------------------------------------------------------===//
/// Create a new OperationInst with the specific fields.
OperationInst *
OperationInst::create(Location location, OperationName name,
ArrayRef<Value *> operands, ArrayRef<Type> resultTypes,
ArrayRef<NamedAttribute> attributes,
ArrayRef<Block *> successors, unsigned numBlockLists,
bool resizableOperandList, MLIRContext *context) {
unsigned numSuccessors = successors.size();
// Input operands are nullptr-separated for each successors in the case of
// terminators, the nullptr aren't actually stored.
unsigned numOperands = operands.size() - numSuccessors;
// Compute the byte size for the instruction and the operand storage.
auto byteSize = totalSizeToAlloc<InstResult, BlockOperand, unsigned,
BlockList, detail::OperandStorage>(
resultTypes.size(), numSuccessors, numSuccessors, numBlockLists,
/*detail::OperandStorage*/ 1);
byteSize += llvm::alignTo(detail::OperandStorage::additionalAllocSize(
numOperands, resizableOperandList),
alignof(OperationInst));
void *rawMem = malloc(byteSize);
// Initialize the OperationInst part of the instruction.
auto inst = ::new (rawMem)
OperationInst(location, name, resultTypes.size(), numSuccessors,
numBlockLists, attributes, context);
assert((numSuccessors == 0 || inst->isTerminator()) &&
"unexpected successors in a non-terminator operation");
// Initialize the block lists.
for (unsigned i = 0; i != numBlockLists; ++i)
new (&inst->getBlockList(i)) BlockList(inst);
// Initialize the results and operands.
new (&inst->getOperandStorage())
detail::OperandStorage(numOperands, resizableOperandList);
auto instResults = inst->getInstResults();
for (unsigned i = 0, e = resultTypes.size(); i != e; ++i)
new (&instResults[i]) InstResult(resultTypes[i], inst);
auto InstOperands = inst->getInstOperands();
// Initialize normal operands.
unsigned operandIt = 0, operandE = operands.size();
unsigned nextOperand = 0;
for (; operandIt != operandE; ++operandIt) {
// Null operands are used as sentinals between successor operand lists. If
// we encounter one here, break and handle the successor operands lists
// separately below.
if (!operands[operandIt])
break;
new (&InstOperands[nextOperand++]) InstOperand(inst, operands[operandIt]);
}
unsigned currentSuccNum = 0;
if (operandIt == operandE) {
// Verify that the amount of sentinal operands is equivalent to the number
// of successors.
assert(currentSuccNum == numSuccessors);
return inst;
}
assert(inst->isTerminator() &&
"Sentinal operand found in non terminator operand list.");
auto instBlockOperands = inst->getBlockOperands();
unsigned *succOperandCountIt = inst->getTrailingObjects<unsigned>();
unsigned *succOperandCountE = succOperandCountIt + numSuccessors;
(void)succOperandCountE;
for (; operandIt != operandE; ++operandIt) {
// If we encounter a sentinal branch to the next operand update the count
// variable.
if (!operands[operandIt]) {
assert(currentSuccNum < numSuccessors);
// After the first iteration update the successor operand count
// variable.
if (currentSuccNum != 0) {
++succOperandCountIt;
assert(succOperandCountIt != succOperandCountE &&
"More sentinal operands than successors.");
}
new (&instBlockOperands[currentSuccNum])
BlockOperand(inst, successors[currentSuccNum]);
*succOperandCountIt = 0;
++currentSuccNum;
continue;
}
new (&InstOperands[nextOperand++]) InstOperand(inst, operands[operandIt]);
++(*succOperandCountIt);
}
// Verify that the amount of sentinal operands is equivalent to the number of
// successors.
assert(currentSuccNum == numSuccessors);
return inst;
}
OperationInst::OperationInst(Location location, OperationName name,
unsigned numResults, unsigned numSuccessors,
unsigned numBlockLists,
ArrayRef<NamedAttribute> attributes,
MLIRContext *context)
: Instruction(location), numResults(numResults), numSuccs(numSuccessors),
numBlockLists(numBlockLists), name(name) {
#ifndef NDEBUG
for (auto elt : attributes)
assert(elt.second != nullptr && "Attributes cannot have null entries");
#endif
this->attrs = AttributeListStorage::get(attributes, context);
}
OperationInst::~OperationInst() {
// Explicitly run the destructors for the operands and results.
getOperandStorage().~OperandStorage();
for (auto &result : getInstResults())
result.~InstResult();
// Explicitly run the destructors for the successors.
if (isTerminator())
for (auto &successor : getBlockOperands())
successor.~BlockOperand();
// Explicitly destroy the block list.
for (auto &blockList : getBlockLists())
blockList.~BlockList();
}
/// Return true if there are no users of any results of this operation.
bool OperationInst::use_empty() const {
for (auto *result : getResults())
if (!result->use_empty())
return false;
return true;
}
ArrayRef<NamedAttribute> OperationInst::getAttrs() const {
if (!attrs)
return {};
return attrs->getElements();
}
void OperationInst::destroy() {
this->~OperationInst();
free(this);
}
/// Return the context this operation is associated with.
MLIRContext *OperationInst::getContext() const {
// If we have a result or operand type, that is a constant time way to get
// to the context.
if (getNumResults())
return getResult(0)->getType().getContext();
if (getNumOperands())
return getOperand(0)->getType().getContext();
// In the very odd case where we have no operands or results, fall back to
// doing a find.
return getFunction()->getContext();
}
bool OperationInst::isReturn() const { return isa<ReturnOp>(); }
void OperationInst::setSuccessor(Block *block, unsigned index) {
assert(index < getNumSuccessors());
getBlockOperands()[index].set(block);
}
auto OperationInst::getNonSuccessorOperands() const
-> llvm::iterator_range<const_operand_iterator> {
return {const_operand_iterator(this, 0),
const_operand_iterator(this, getSuccessorOperandIndex(0))};
}
auto OperationInst::getNonSuccessorOperands()
-> llvm::iterator_range<operand_iterator> {
return {operand_iterator(this, 0),
operand_iterator(this, getSuccessorOperandIndex(0))};
}
auto OperationInst::getSuccessorOperands(unsigned index) const
-> llvm::iterator_range<const_operand_iterator> {
assert(isTerminator() && "Only terminators have successors.");
unsigned succOperandIndex = getSuccessorOperandIndex(index);
return {const_operand_iterator(this, succOperandIndex),
const_operand_iterator(this, succOperandIndex +
getNumSuccessorOperands(index))};
}
auto OperationInst::getSuccessorOperands(unsigned index)
-> llvm::iterator_range<operand_iterator> {
assert(isTerminator() && "Only terminators have successors.");
unsigned succOperandIndex = getSuccessorOperandIndex(index);
return {operand_iterator(this, succOperandIndex),
operand_iterator(this,
succOperandIndex + getNumSuccessorOperands(index))};
}
/// If an attribute exists with the specified name, change it to the new
/// value. Otherwise, add a new attribute with the specified name/value.
void OperationInst::setAttr(Identifier name, Attribute value) {
assert(value && "attributes may never be null");
auto origAttrs = getAttrs();
SmallVector<NamedAttribute, 8> newAttrs(origAttrs.begin(), origAttrs.end());
auto *context = getContext();
// If we already have this attribute, replace it.
for (auto &elt : newAttrs)
if (elt.first == name) {
elt.second = value;
attrs = AttributeListStorage::get(newAttrs, context);
return;
}
// Otherwise, add it.
newAttrs.push_back({name, value});
attrs = AttributeListStorage::get(newAttrs, context);
}
/// Remove the attribute with the specified name if it exists. The return
/// value indicates whether the attribute was present or not.
auto OperationInst::removeAttr(Identifier name) -> RemoveResult {
auto origAttrs = getAttrs();
for (unsigned i = 0, e = origAttrs.size(); i != e; ++i) {
if (origAttrs[i].first == name) {
SmallVector<NamedAttribute, 8> newAttrs;
newAttrs.reserve(origAttrs.size() - 1);
newAttrs.append(origAttrs.begin(), origAttrs.begin() + i);
newAttrs.append(origAttrs.begin() + i + 1, origAttrs.end());
attrs = AttributeListStorage::get(newAttrs, getContext());
return RemoveResult::Removed;
}
}
return RemoveResult::NotFound;
}
/// Attempt to constant fold this operation with the specified constant
/// operand values. If successful, this returns false and fills in the
/// results vector. If not, this returns true and results is unspecified.
bool OperationInst::constantFold(ArrayRef<Attribute> operands,
SmallVectorImpl<Attribute> &results) const {
if (auto *abstractOp = getAbstractOperation()) {
// If we have a registered operation definition matching this one, use it to
// try to constant fold the operation.
if (!abstractOp->constantFoldHook(this, operands, results))
return false;
// Otherwise, fall back on the dialect hook to handle it.
return abstractOp->dialect.constantFoldHook(this, operands, results);
}
// If this operation hasn't been registered or doesn't have abstract
// operation, fall back to a dialect which matches the prefix.
auto opName = getName().getStringRef();
auto dialectPrefix = opName.split('.').first;
if (auto *dialect = getContext()->getRegisteredDialect(dialectPrefix)) {
return dialect->constantFoldHook(this, operands, results);
}
return true;
}
/// Attempt to fold this operation using the Op's registered foldHook.
bool OperationInst::fold(SmallVectorImpl<Value *> &results) {
if (auto *abstractOp = getAbstractOperation()) {
// If we have a registered operation definition matching this one, use it to
// try to constant fold the operation.
if (!abstractOp->foldHook(this, results))
return false;
}
return true;
}
/// Emit an error with the op name prefixed, like "'dim' op " which is
/// convenient for verifiers.
bool OperationInst::emitOpError(const Twine &message) const {
return emitError(Twine('\'') + getName().getStringRef() + "' op " + message);
}
//===----------------------------------------------------------------------===//
// Instruction Cloning
//===----------------------------------------------------------------------===//
/// Create a deep copy of this instruction, remapping any operands that use
/// values outside of the instruction using the map that is provided (leaving
/// them alone if no entry is present). Replaces references to cloned
/// sub-instructions to the corresponding instruction that is copied, and adds
/// those mappings to the map.
Instruction *Instruction::clone(BlockAndValueMapping &mapper,
MLIRContext *context) const {
SmallVector<Value *, 8> operands;
SmallVector<Block *, 2> successors;
auto *opInst = cast<OperationInst>(this);
operands.reserve(getNumOperands() + opInst->getNumSuccessors());
if (!opInst->isTerminator()) {
// Non-terminators just add all the operands.
for (auto *opValue : getOperands())
operands.push_back(mapper.lookupOrDefault(const_cast<Value *>(opValue)));
} else {
// We add the operands separated by nullptr's for each successor.
unsigned firstSuccOperand = opInst->getNumSuccessors()
? opInst->getSuccessorOperandIndex(0)
: opInst->getNumOperands();
auto InstOperands = opInst->getInstOperands();
unsigned i = 0;
for (; i != firstSuccOperand; ++i)
operands.push_back(
mapper.lookupOrDefault(const_cast<Value *>(InstOperands[i].get())));
successors.reserve(opInst->getNumSuccessors());
for (unsigned succ = 0, e = opInst->getNumSuccessors(); succ != e; ++succ) {
successors.push_back(mapper.lookupOrDefault(
const_cast<Block *>(opInst->getSuccessor(succ))));
// Add sentinel to delineate successor operands.
operands.push_back(nullptr);
// Remap the successors operands.
for (auto *operand : opInst->getSuccessorOperands(succ))
operands.push_back(
mapper.lookupOrDefault(const_cast<Value *>(operand)));
}
}
SmallVector<Type, 8> resultTypes;
resultTypes.reserve(opInst->getNumResults());
for (auto *result : opInst->getResults())
resultTypes.push_back(result->getType());
unsigned numBlockLists = opInst->getNumBlockLists();
auto *newOp = OperationInst::create(
getLoc(), opInst->getName(), operands, resultTypes, opInst->getAttrs(),
successors, numBlockLists, opInst->hasResizableOperandsList(), context);
// Clone the block lists.
for (unsigned i = 0; i != numBlockLists; ++i)
opInst->getBlockList(i).cloneInto(&newOp->getBlockList(i), mapper, context);
// Remember the mapping of any results.
for (unsigned i = 0, e = opInst->getNumResults(); i != e; ++i)
mapper.map(opInst->getResult(i), newOp->getResult(i));
return newOp;
}
Instruction *Instruction::clone(MLIRContext *context) const {
BlockAndValueMapping mapper;
return clone(mapper, context);
}