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//===- RewriterGen.cpp - MLIR pattern rewriter generator ------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// RewriterGen uses pattern rewrite definitions to generate rewriter matchers.
//
//===----------------------------------------------------------------------===//
#include "mlir/Support/IndentedOstream.h"
#include "mlir/TableGen/Attribute.h"
#include "mlir/TableGen/Format.h"
#include "mlir/TableGen/GenInfo.h"
#include "mlir/TableGen/Operator.h"
#include "mlir/TableGen/Pattern.h"
#include "mlir/TableGen/Predicate.h"
#include "mlir/TableGen/Type.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/StringSet.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/FormatAdapters.h"
#include "llvm/Support/PrettyStackTrace.h"
#include "llvm/Support/Signals.h"
#include "llvm/TableGen/Error.h"
#include "llvm/TableGen/Main.h"
#include "llvm/TableGen/Record.h"
#include "llvm/TableGen/TableGenBackend.h"
using namespace mlir;
using namespace mlir::tblgen;
using llvm::formatv;
using llvm::Record;
using llvm::RecordKeeper;
#define DEBUG_TYPE "mlir-tblgen-rewritergen"
namespace llvm {
template <>
struct format_provider<mlir::tblgen::Pattern::IdentifierLine> {
static void format(const mlir::tblgen::Pattern::IdentifierLine &v,
raw_ostream &os, StringRef style) {
os << v.first << ":" << v.second;
}
};
} // end namespace llvm
//===----------------------------------------------------------------------===//
// PatternEmitter
//===----------------------------------------------------------------------===//
namespace {
class PatternEmitter {
public:
PatternEmitter(Record *pat, RecordOperatorMap *mapper, raw_ostream &os);
// Emits the mlir::RewritePattern struct named `rewriteName`.
void emit(StringRef rewriteName);
private:
// Emits the code for matching ops.
void emitMatchLogic(DagNode tree, StringRef opName);
// Emits the code for rewriting ops.
void emitRewriteLogic();
//===--------------------------------------------------------------------===//
// Match utilities
//===--------------------------------------------------------------------===//
// Emits C++ statements for matching the DAG structure.
void emitMatch(DagNode tree, StringRef name, int depth);
// Emits C++ statements for matching using a native code call.
void emitNativeCodeMatch(DagNode tree, StringRef name, int depth);
// Emits C++ statements for matching the op constrained by the given DAG
// `tree` returning the op's variable name.
void emitOpMatch(DagNode tree, StringRef opName, int depth);
// Emits C++ statements for matching the `argIndex`-th argument of the given
// DAG `tree` as an operand.
void emitOperandMatch(DagNode tree, StringRef opName, int argIndex,
int depth);
// Emits C++ statements for matching the `argIndex`-th argument of the given
// DAG `tree` as an attribute.
void emitAttributeMatch(DagNode tree, StringRef opName, int argIndex,
int depth);
// Emits C++ for checking a match with a corresponding match failure
// diagnostic.
void emitMatchCheck(StringRef opName, const FmtObjectBase &matchFmt,
const llvm::formatv_object_base &failureFmt);
// Emits C++ for checking a match with a corresponding match failure
// diagnostics.
void emitMatchCheck(StringRef opName, const std::string &matchStr,
const std::string &failureStr);
//===--------------------------------------------------------------------===//
// Rewrite utilities
//===--------------------------------------------------------------------===//
// The entry point for handling a result pattern rooted at `resultTree`. This
// method dispatches to concrete handlers according to `resultTree`'s kind and
// returns a symbol representing the whole value pack. Callers are expected to
// further resolve the symbol according to the specific use case.
//
// `depth` is the nesting level of `resultTree`; 0 means top-level result
// pattern. For top-level result pattern, `resultIndex` indicates which result
// of the matched root op this pattern is intended to replace, which can be
// used to deduce the result type of the op generated from this result
// pattern.
std::string handleResultPattern(DagNode resultTree, int resultIndex,
int depth);
// Emits the C++ statement to replace the matched DAG with a value built via
// calling native C++ code.
std::string handleReplaceWithNativeCodeCall(DagNode resultTree, int depth);
// Returns the symbol of the old value serving as the replacement.
StringRef handleReplaceWithValue(DagNode tree);
// Returns the location value to use.
std::pair<bool, std::string> getLocation(DagNode tree);
// Returns the location value to use.
std::string handleLocationDirective(DagNode tree);
// Emits the C++ statement to build a new op out of the given DAG `tree` and
// returns the variable name that this op is assigned to. If the root op in
// DAG `tree` has a specified name, the created op will be assigned to a
// variable of the given name. Otherwise, a unique name will be used as the
// result value name.
std::string handleOpCreation(DagNode tree, int resultIndex, int depth);
using ChildNodeIndexNameMap = DenseMap<unsigned, std::string>;
// Emits a local variable for each value and attribute to be used for creating
// an op.
void createSeparateLocalVarsForOpArgs(DagNode node,
ChildNodeIndexNameMap &childNodeNames);
// Emits the concrete arguments used to call an op's builder.
void supplyValuesForOpArgs(DagNode node,
const ChildNodeIndexNameMap &childNodeNames,
int depth);
// Emits the local variables for holding all values as a whole and all named
// attributes as a whole to be used for creating an op.
void createAggregateLocalVarsForOpArgs(
DagNode node, const ChildNodeIndexNameMap &childNodeNames, int depth);
// Returns the C++ expression to construct a constant attribute of the given
// `value` for the given attribute kind `attr`.
std::string handleConstantAttr(Attribute attr, StringRef value);
// Returns the C++ expression to build an argument from the given DAG `leaf`.
// `patArgName` is used to bound the argument to the source pattern.
std::string handleOpArgument(DagLeaf leaf, StringRef patArgName);
//===--------------------------------------------------------------------===//
// General utilities
//===--------------------------------------------------------------------===//
// Collects all of the operations within the given dag tree.
void collectOps(DagNode tree, llvm::SmallPtrSetImpl<const Operator *> &ops);
// Returns a unique symbol for a local variable of the given `op`.
std::string getUniqueSymbol(const Operator *op);
//===--------------------------------------------------------------------===//
// Symbol utilities
//===--------------------------------------------------------------------===//
// Returns how many static values the given DAG `node` correspond to.
int getNodeValueCount(DagNode node);
private:
// Pattern instantiation location followed by the location of multiclass
// prototypes used. This is intended to be used as a whole to
// PrintFatalError() on errors.
ArrayRef<llvm::SMLoc> loc;
// Op's TableGen Record to wrapper object.
RecordOperatorMap *opMap;
// Handy wrapper for pattern being emitted.
Pattern pattern;
// Map for all bound symbols' info.
SymbolInfoMap symbolInfoMap;
// The next unused ID for newly created values.
unsigned nextValueId;
raw_indented_ostream os;
// Format contexts containing placeholder substitutions.
FmtContext fmtCtx;
// Number of op processed.
int opCounter = 0;
};
} // end anonymous namespace
PatternEmitter::PatternEmitter(Record *pat, RecordOperatorMap *mapper,
raw_ostream &os)
: loc(pat->getLoc()), opMap(mapper), pattern(pat, mapper),
symbolInfoMap(pat->getLoc()), nextValueId(0), os(os) {
fmtCtx.withBuilder("rewriter");
}
std::string PatternEmitter::handleConstantAttr(Attribute attr,
StringRef value) {
if (!attr.isConstBuildable())
PrintFatalError(loc, "Attribute " + attr.getAttrDefName() +
" does not have the 'constBuilderCall' field");
// TODO: Verify the constants here
return std::string(tgfmt(attr.getConstBuilderTemplate(), &fmtCtx, value));
}
// Helper function to match patterns.
void PatternEmitter::emitMatch(DagNode tree, StringRef name, int depth) {
if (tree.isNativeCodeCall()) {
emitNativeCodeMatch(tree, name, depth);
return;
}
if (tree.isOperation()) {
emitOpMatch(tree, name, depth);
return;
}
PrintFatalError(loc, "encountered non-op, non-NativeCodeCall match.");
}
// Helper function to match patterns.
void PatternEmitter::emitNativeCodeMatch(DagNode tree, StringRef opName,
int depth) {
LLVM_DEBUG(llvm::dbgs() << "handle NativeCodeCall matcher pattern: ");
LLVM_DEBUG(tree.print(llvm::dbgs()));
LLVM_DEBUG(llvm::dbgs() << '\n');
// TODO(suderman): iterate through arguments, determine their types, output
// names.
SmallVector<std::string, 8> capture(8);
if (tree.getNumArgs() > 8) {
PrintFatalError(loc,
"unsupported NativeCodeCall matcher argument numbers: " +
Twine(tree.getNumArgs()));
}
raw_indented_ostream::DelimitedScope scope(os);
os << "if(!" << opName << ") return failure();\n";
for (int i = 0, e = tree.getNumArgs(); i != e; ++i) {
std::string argName = formatv("arg{0}_{1}", depth, i);
if (DagNode argTree = tree.getArgAsNestedDag(i)) {
os << "Value " << argName << ";\n";
} else {
auto leaf = tree.getArgAsLeaf(i);
if (leaf.isAttrMatcher() || leaf.isConstantAttr()) {
os << "Attribute " << argName << ";\n";
} else if (leaf.isOperandMatcher()) {
os << "Operation " << argName << ";\n";
}
}
capture[i] = std::move(argName);
}
bool hasLocationDirective;
std::string locToUse;
std::tie(hasLocationDirective, locToUse) = getLocation(tree);
auto fmt = tree.getNativeCodeTemplate();
auto nativeCodeCall = std::string(tgfmt(
fmt, &fmtCtx.addSubst("_loc", locToUse), opName, capture[0], capture[1],
capture[2], capture[3], capture[4], capture[5], capture[6], capture[7]));
os << "if (failed(" << nativeCodeCall << ")) return failure();\n";
for (int i = 0, e = tree.getNumArgs(); i != e; ++i) {
auto name = tree.getArgName(i);
if (!name.empty() && name != "_") {
os << formatv("{0} = {1};\n", name, capture[i]);
}
}
for (int i = 0, e = tree.getNumArgs(); i != e; ++i) {
std::string argName = capture[i];
// Handle nested DAG construct first
if (DagNode argTree = tree.getArgAsNestedDag(i)) {
PrintFatalError(
loc, formatv("Matching nested tree in NativeCodecall not support for "
"{0} as arg {1}",
argName, i));
}
DagLeaf leaf = tree.getArgAsLeaf(i);
auto constraint = leaf.getAsConstraint();
auto self = formatv("{0}", argName);
emitMatchCheck(
opName,
tgfmt(constraint.getConditionTemplate(), &fmtCtx.withSelf(self)),
formatv("\"operand {0} of native code call '{1}' failed to satisfy "
"constraint: "
"'{2}'\"",
i, tree.getNativeCodeTemplate(), constraint.getDescription()));
}
LLVM_DEBUG(llvm::dbgs() << "done emitting match for native code call\n");
}
// Helper function to match patterns.
void PatternEmitter::emitOpMatch(DagNode tree, StringRef opName, int depth) {
Operator &op = tree.getDialectOp(opMap);
LLVM_DEBUG(llvm::dbgs() << "start emitting match for op '"
<< op.getOperationName() << "' at depth " << depth
<< '\n');
std::string castedName = formatv("castedOp{0}", depth);
os << formatv("auto {0} = ::llvm::dyn_cast_or_null<{2}>({1}); "
"(void){0};\n",
castedName, opName, op.getQualCppClassName());
// Skip the operand matching at depth 0 as the pattern rewriter already does.
if (depth != 0) {
// Skip if there is no defining operation (e.g., arguments to function).
os << formatv("if (!{0}) return failure();\n", castedName);
}
if (tree.getNumArgs() != op.getNumArgs()) {
PrintFatalError(loc, formatv("op '{0}' argument number mismatch: {1} in "
"pattern vs. {2} in definition",
op.getOperationName(), tree.getNumArgs(),
op.getNumArgs()));
}
// If the operand's name is set, set to that variable.
auto name = tree.getSymbol();
if (!name.empty())
os << formatv("{0} = {1};\n", name, castedName);
for (int i = 0, e = tree.getNumArgs(), nextOperand = 0; i != e; ++i) {
auto opArg = op.getArg(i);
std::string argName = formatv("op{0}", depth + 1);
// Handle nested DAG construct first
if (DagNode argTree = tree.getArgAsNestedDag(i)) {
if (auto *operand = opArg.dyn_cast<NamedTypeConstraint *>()) {
if (operand->isVariableLength()) {
auto error = formatv("use nested DAG construct to match op {0}'s "
"variadic operand #{1} unsupported now",
op.getOperationName(), i);
PrintFatalError(loc, error);
}
}
os << "{\n";
// Attributes don't count for getODSOperands.
os.indent() << formatv(
"auto *{0} = "
"(*{1}.getODSOperands({2}).begin()).getDefiningOp();\n",
argName, castedName, nextOperand++);
emitMatch(argTree, argName, depth + 1);
os << formatv("tblgen_ops[{0}] = {1};\n", ++opCounter, argName);
os.unindent() << "}\n";
continue;
}
// Next handle DAG leaf: operand or attribute
if (opArg.is<NamedTypeConstraint *>()) {
// emitOperandMatch's argument indexing counts attributes.
emitOperandMatch(tree, castedName, i, depth);
++nextOperand;
} else if (opArg.is<NamedAttribute *>()) {
emitAttributeMatch(tree, opName, i, depth);
} else {
PrintFatalError(loc, "unhandled case when matching op");
}
}
LLVM_DEBUG(llvm::dbgs() << "done emitting match for op '"
<< op.getOperationName() << "' at depth " << depth
<< '\n');
}
void PatternEmitter::emitOperandMatch(DagNode tree, StringRef opName,
int argIndex, int depth) {
Operator &op = tree.getDialectOp(opMap);
auto *operand = op.getArg(argIndex).get<NamedTypeConstraint *>();
auto matcher = tree.getArgAsLeaf(argIndex);
// If a constraint is specified, we need to generate C++ statements to
// check the constraint.
if (!matcher.isUnspecified()) {
if (!matcher.isOperandMatcher()) {
PrintFatalError(
loc, formatv("the {1}-th argument of op '{0}' should be an operand",
op.getOperationName(), argIndex + 1));
}
// Only need to verify if the matcher's type is different from the one
// of op definition.
Constraint constraint = matcher.getAsConstraint();
if (operand->constraint != constraint) {
if (operand->isVariableLength()) {
auto error = formatv(
"further constrain op {0}'s variadic operand #{1} unsupported now",
op.getOperationName(), argIndex);
PrintFatalError(loc, error);
}
auto self = formatv("(*{0}.getODSOperands({1}).begin()).getType()",
opName, argIndex);
emitMatchCheck(
opName,
tgfmt(constraint.getConditionTemplate(), &fmtCtx.withSelf(self)),
formatv("\"operand {0} of op '{1}' failed to satisfy constraint: "
"'{2}'\"",
operand - op.operand_begin(), op.getOperationName(),
constraint.getDescription()));
}
}
// Capture the value
auto name = tree.getArgName(argIndex);
// `$_` is a special symbol to ignore op argument matching.
if (!name.empty() && name != "_") {
// We need to subtract the number of attributes before this operand to get
// the index in the operand list.
auto numPrevAttrs = std::count_if(
op.arg_begin(), op.arg_begin() + argIndex,
[](const Argument &arg) { return arg.is<NamedAttribute *>(); });
auto res = symbolInfoMap.findBoundSymbol(name, op, argIndex);
os << formatv("{0} = {1}.getODSOperands({2});\n",
res->second.getVarName(name), opName,
argIndex - numPrevAttrs);
}
}
void PatternEmitter::emitAttributeMatch(DagNode tree, StringRef opName,
int argIndex, int depth) {
Operator &op = tree.getDialectOp(opMap);
auto *namedAttr = op.getArg(argIndex).get<NamedAttribute *>();
const auto &attr = namedAttr->attr;
os << "{\n";
os.indent() << formatv("auto tblgen_attr = {0}->getAttrOfType<{1}>(\"{2}\");"
"(void)tblgen_attr;\n",
opName, attr.getStorageType(), namedAttr->name);
// TODO: This should use getter method to avoid duplication.
if (attr.hasDefaultValue()) {
os << "if (!tblgen_attr) tblgen_attr = "
<< std::string(tgfmt(attr.getConstBuilderTemplate(), &fmtCtx,
attr.getDefaultValue()))
<< ";\n";
} else if (attr.isOptional()) {
// For a missing attribute that is optional according to definition, we
// should just capture a mlir::Attribute() to signal the missing state.
// That is precisely what getAttr() returns on missing attributes.
} else {
emitMatchCheck(opName, tgfmt("tblgen_attr", &fmtCtx),
formatv("\"expected op '{0}' to have attribute '{1}' "
"of type '{2}'\"",
op.getOperationName(), namedAttr->name,
attr.getStorageType()));
}
auto matcher = tree.getArgAsLeaf(argIndex);
if (!matcher.isUnspecified()) {
if (!matcher.isAttrMatcher()) {
PrintFatalError(
loc, formatv("the {1}-th argument of op '{0}' should be an attribute",
op.getOperationName(), argIndex + 1));
}
// If a constraint is specified, we need to generate C++ statements to
// check the constraint.
emitMatchCheck(
opName,
tgfmt(matcher.getConditionTemplate(), &fmtCtx.withSelf("tblgen_attr")),
formatv("\"op '{0}' attribute '{1}' failed to satisfy constraint: "
"{2}\"",
op.getOperationName(), namedAttr->name,
matcher.getAsConstraint().getDescription()));
}
// Capture the value
auto name = tree.getArgName(argIndex);
// `$_` is a special symbol to ignore op argument matching.
if (!name.empty() && name != "_") {
os << formatv("{0} = tblgen_attr;\n", name);
}
os.unindent() << "}\n";
}
void PatternEmitter::emitMatchCheck(
StringRef opName, const FmtObjectBase &matchFmt,
const llvm::formatv_object_base &failureFmt) {
emitMatchCheck(opName, matchFmt.str(), failureFmt.str());
}
void PatternEmitter::emitMatchCheck(StringRef opName,
const std::string &matchStr,
const std::string &failureStr) {
os << "if (!(" << matchStr << "))";
os.scope("{\n", "\n}\n").os << "return rewriter.notifyMatchFailure(" << opName
<< ", [&](::mlir::Diagnostic &diag) {\n diag << "
<< failureStr << ";\n});";
}
void PatternEmitter::emitMatchLogic(DagNode tree, StringRef opName) {
LLVM_DEBUG(llvm::dbgs() << "--- start emitting match logic ---\n");
int depth = 0;
emitMatch(tree, opName, depth);
for (auto &appliedConstraint : pattern.getConstraints()) {
auto &constraint = appliedConstraint.constraint;
auto &entities = appliedConstraint.entities;
auto condition = constraint.getConditionTemplate();
if (isa<TypeConstraint>(constraint)) {
auto self = formatv("({0}.getType())",
symbolInfoMap.getValueAndRangeUse(entities.front()));
emitMatchCheck(
opName, tgfmt(condition, &fmtCtx.withSelf(self.str())),
formatv("\"value entity '{0}' failed to satisfy constraint: {1}\"",
entities.front(), constraint.getDescription()));
} else if (isa<AttrConstraint>(constraint)) {
PrintFatalError(
loc, "cannot use AttrConstraint in Pattern multi-entity constraints");
} else {
// TODO: replace formatv arguments with the exact specified
// args.
if (entities.size() > 4) {
PrintFatalError(loc, "only support up to 4-entity constraints now");
}
SmallVector<std::string, 4> names;
int i = 0;
for (int e = entities.size(); i < e; ++i)
names.push_back(symbolInfoMap.getValueAndRangeUse(entities[i]));
std::string self = appliedConstraint.self;
if (!self.empty())
self = symbolInfoMap.getValueAndRangeUse(self);
for (; i < 4; ++i)
names.push_back("<unused>");
emitMatchCheck(opName,
tgfmt(condition, &fmtCtx.withSelf(self), names[0],
names[1], names[2], names[3]),
formatv("\"entities '{0}' failed to satisfy constraint: "
"{1}\"",
llvm::join(entities, ", "),
constraint.getDescription()));
}
}
// Some of the operands could be bound to the same symbol name, we need
// to enforce equality constraint on those.
// TODO: we should be able to emit equality checks early
// and short circuit unnecessary work if vars are not equal.
for (auto symbolInfoIt = symbolInfoMap.begin();
symbolInfoIt != symbolInfoMap.end();) {
auto range = symbolInfoMap.getRangeOfEqualElements(symbolInfoIt->first);
auto startRange = range.first;
auto endRange = range.second;
auto firstOperand = symbolInfoIt->second.getVarName(symbolInfoIt->first);
for (++startRange; startRange != endRange; ++startRange) {
auto secondOperand = startRange->second.getVarName(symbolInfoIt->first);
emitMatchCheck(
opName,
formatv("*{0}.begin() == *{1}.begin()", firstOperand, secondOperand),
formatv("\"Operands '{0}' and '{1}' must be equal\"", firstOperand,
secondOperand));
}
symbolInfoIt = endRange;
}
LLVM_DEBUG(llvm::dbgs() << "--- done emitting match logic ---\n");
}
void PatternEmitter::collectOps(DagNode tree,
llvm::SmallPtrSetImpl<const Operator *> &ops) {
// Check if this tree is an operation.
if (tree.isOperation()) {
const Operator &op = tree.getDialectOp(opMap);
LLVM_DEBUG(llvm::dbgs()
<< "found operation " << op.getOperationName() << '\n');
ops.insert(&op);
}
// Recurse the arguments of the tree.
for (unsigned i = 0, e = tree.getNumArgs(); i != e; ++i)
if (auto child = tree.getArgAsNestedDag(i))
collectOps(child, ops);
}
void PatternEmitter::emit(StringRef rewriteName) {
// Get the DAG tree for the source pattern.
DagNode sourceTree = pattern.getSourcePattern();
const Operator &rootOp = pattern.getSourceRootOp();
auto rootName = rootOp.getOperationName();
// Collect the set of result operations.
llvm::SmallPtrSet<const Operator *, 4> resultOps;
LLVM_DEBUG(llvm::dbgs() << "start collecting ops used in result patterns\n");
for (unsigned i = 0, e = pattern.getNumResultPatterns(); i != e; ++i) {
collectOps(pattern.getResultPattern(i), resultOps);
}
LLVM_DEBUG(llvm::dbgs() << "done collecting ops used in result patterns\n");
// Emit RewritePattern for Pattern.
auto locs = pattern.getLocation();
os << formatv("/* Generated from:\n {0:$[ instantiating\n ]}\n*/\n",
make_range(locs.rbegin(), locs.rend()));
os << formatv(R"(struct {0} : public ::mlir::RewritePattern {
{0}(::mlir::MLIRContext *context)
: ::mlir::RewritePattern("{1}", {{)",
rewriteName, rootName);
// Sort result operators by name.
llvm::SmallVector<const Operator *, 4> sortedResultOps(resultOps.begin(),
resultOps.end());
llvm::sort(sortedResultOps, [&](const Operator *lhs, const Operator *rhs) {
return lhs->getOperationName() < rhs->getOperationName();
});
llvm::interleaveComma(sortedResultOps, os, [&](const Operator *op) {
os << '"' << op->getOperationName() << '"';
});
os << formatv(R"(}, {0}, context) {{})", pattern.getBenefit()) << "\n";
// Emit matchAndRewrite() function.
{
auto classScope = os.scope();
os.reindent(R"(
::mlir::LogicalResult matchAndRewrite(::mlir::Operation *op0,
::mlir::PatternRewriter &rewriter) const override {)")
<< '\n';
{
auto functionScope = os.scope();
// Register all symbols bound in the source pattern.
pattern.collectSourcePatternBoundSymbols(symbolInfoMap);
LLVM_DEBUG(llvm::dbgs()
<< "start creating local variables for capturing matches\n");
os << "// Variables for capturing values and attributes used while "
"creating ops\n";
// Create local variables for storing the arguments and results bound
// to symbols.
for (const auto &symbolInfoPair : symbolInfoMap) {
const auto &symbol = symbolInfoPair.first;
const auto &info = symbolInfoPair.second;
os << info.getVarDecl(symbol);
}
// TODO: capture ops with consistent numbering so that it can be
// reused for fused loc.
os << formatv("::mlir::Operation *tblgen_ops[{0}];\n\n",
pattern.getSourcePattern().getNumOps());
LLVM_DEBUG(llvm::dbgs()
<< "done creating local variables for capturing matches\n");
os << "// Match\n";
os << "tblgen_ops[0] = op0;\n";
emitMatchLogic(sourceTree, "op0");
os << "\n// Rewrite\n";
emitRewriteLogic();
os << "return ::mlir::success();\n";
}
os << "};\n";
}
os << "};\n\n";
}
void PatternEmitter::emitRewriteLogic() {
LLVM_DEBUG(llvm::dbgs() << "--- start emitting rewrite logic ---\n");
const Operator &rootOp = pattern.getSourceRootOp();
int numExpectedResults = rootOp.getNumResults();
int numResultPatterns = pattern.getNumResultPatterns();
// First register all symbols bound to ops generated in result patterns.
pattern.collectResultPatternBoundSymbols(symbolInfoMap);
// Only the last N static values generated are used to replace the matched
// root N-result op. We need to calculate the starting index (of the results
// of the matched op) each result pattern is to replace.
SmallVector<int, 4> offsets(numResultPatterns + 1, numExpectedResults);
// If we don't need to replace any value at all, set the replacement starting
// index as the number of result patterns so we skip all of them when trying
// to replace the matched op's results.
int replStartIndex = numExpectedResults == 0 ? numResultPatterns : -1;
for (int i = numResultPatterns - 1; i >= 0; --i) {
auto numValues = getNodeValueCount(pattern.getResultPattern(i));
offsets[i] = offsets[i + 1] - numValues;
if (offsets[i] == 0) {
if (replStartIndex == -1)
replStartIndex = i;
} else if (offsets[i] < 0 && offsets[i + 1] > 0) {
auto error = formatv(
"cannot use the same multi-result op '{0}' to generate both "
"auxiliary values and values to be used for replacing the matched op",
pattern.getResultPattern(i).getSymbol());
PrintFatalError(loc, error);
}
}
if (offsets.front() > 0) {
const char error[] = "no enough values generated to replace the matched op";
PrintFatalError(loc, error);
}
os << "auto odsLoc = rewriter.getFusedLoc({";
for (int i = 0, e = pattern.getSourcePattern().getNumOps(); i != e; ++i) {
os << (i ? ", " : "") << "tblgen_ops[" << i << "]->getLoc()";
}
os << "}); (void)odsLoc;\n";
// Process auxiliary result patterns.
for (int i = 0; i < replStartIndex; ++i) {
DagNode resultTree = pattern.getResultPattern(i);
auto val = handleResultPattern(resultTree, offsets[i], 0);
// Normal op creation will be streamed to `os` by the above call; but
// NativeCodeCall will only be materialized to `os` if it is used. Here
// we are handling auxiliary patterns so we want the side effect even if
// NativeCodeCall is not replacing matched root op's results.
if (resultTree.isNativeCodeCall())
os << val << ";\n";
}
if (numExpectedResults == 0) {
assert(replStartIndex >= numResultPatterns &&
"invalid auxiliary vs. replacement pattern division!");
// No result to replace. Just erase the op.
os << "rewriter.eraseOp(op0);\n";
} else {
// Process replacement result patterns.
os << "::llvm::SmallVector<::mlir::Value, 4> tblgen_repl_values;\n";
for (int i = replStartIndex; i < numResultPatterns; ++i) {
DagNode resultTree = pattern.getResultPattern(i);
auto val = handleResultPattern(resultTree, offsets[i], 0);
os << "\n";
// Resolve each symbol for all range use so that we can loop over them.
// We need an explicit cast to `SmallVector` to capture the cases where
// `{0}` resolves to an `Operation::result_range` as well as cases that
// are not iterable (e.g. vector that gets wrapped in additional braces by
// RewriterGen).
// TODO: Revisit the need for materializing a vector.
os << symbolInfoMap.getAllRangeUse(
val,
"for (auto v: ::llvm::SmallVector<::mlir::Value, 4>{ {0} }) {{\n"
" tblgen_repl_values.push_back(v);\n}\n",
"\n");
}
os << "\nrewriter.replaceOp(op0, tblgen_repl_values);\n";
}
LLVM_DEBUG(llvm::dbgs() << "--- done emitting rewrite logic ---\n");
}
std::string PatternEmitter::getUniqueSymbol(const Operator *op) {
return std::string(
formatv("tblgen_{0}_{1}", op->getCppClassName(), nextValueId++));
}
std::string PatternEmitter::handleResultPattern(DagNode resultTree,
int resultIndex, int depth) {
LLVM_DEBUG(llvm::dbgs() << "handle result pattern: ");
LLVM_DEBUG(resultTree.print(llvm::dbgs()));
LLVM_DEBUG(llvm::dbgs() << '\n');
if (resultTree.isLocationDirective()) {
PrintFatalError(loc,
"location directive can only be used with op creation");
}
if (resultTree.isNativeCodeCall()) {
auto symbol = handleReplaceWithNativeCodeCall(resultTree, depth);
symbolInfoMap.bindValue(symbol);
return symbol;
}
if (resultTree.isReplaceWithValue())
return handleReplaceWithValue(resultTree).str();
// Normal op creation.
auto symbol = handleOpCreation(resultTree, resultIndex, depth);
if (resultTree.getSymbol().empty()) {
// This is an op not explicitly bound to a symbol in the rewrite rule.
// Register the auto-generated symbol for it.
symbolInfoMap.bindOpResult(symbol, pattern.getDialectOp(resultTree));
}
return symbol;
}
StringRef PatternEmitter::handleReplaceWithValue(DagNode tree) {
assert(tree.isReplaceWithValue());
if (tree.getNumArgs() != 1) {
PrintFatalError(
loc, "replaceWithValue directive must take exactly one argument");
}
if (!tree.getSymbol().empty()) {
PrintFatalError(loc, "cannot bind symbol to replaceWithValue");
}
return tree.getArgName(0);
}
std::string PatternEmitter::handleLocationDirective(DagNode tree) {
assert(tree.isLocationDirective());
auto lookUpArgLoc = [this, &tree](int idx) {
const auto *const lookupFmt = "(*{0}.begin()).getLoc()";
return symbolInfoMap.getAllRangeUse(tree.getArgName(idx), lookupFmt);
};
if (tree.getNumArgs() == 0)
llvm::PrintFatalError(
"At least one argument to location directive required");
if (!tree.getSymbol().empty())
PrintFatalError(loc, "cannot bind symbol to location");
if (tree.getNumArgs() == 1) {
DagLeaf leaf = tree.getArgAsLeaf(0);
if (leaf.isStringAttr())
return formatv("::mlir::NameLoc::get(rewriter.getIdentifier(\"{0}\"), "
"rewriter.getContext())",
leaf.getStringAttr())
.str();
return lookUpArgLoc(0);
}
std::string ret;
llvm::raw_string_ostream os(ret);
std::string strAttr;
os << "rewriter.getFusedLoc({";
bool first = true;
for (int i = 0, e = tree.getNumArgs(); i != e; ++i) {
DagLeaf leaf = tree.getArgAsLeaf(i);
// Handle the optional string value.
if (leaf.isStringAttr()) {
if (!strAttr.empty())
llvm::PrintFatalError("Only one string attribute may be specified");
strAttr = leaf.getStringAttr();
continue;
}
os << (first ? "" : ", ") << lookUpArgLoc(i);
first = false;
}
os << "}";
if (!strAttr.empty()) {
os << ", rewriter.getStringAttr(\"" << strAttr << "\")";
}
os << ")";
return os.str();
}
std::string PatternEmitter::handleOpArgument(DagLeaf leaf,
StringRef patArgName) {
if (leaf.isStringAttr())
PrintFatalError(loc, "raw string not supported as argument");
if (leaf.isConstantAttr()) {
auto constAttr = leaf.getAsConstantAttr();
return handleConstantAttr(constAttr.getAttribute(),
constAttr.getConstantValue());
}
if (leaf.isEnumAttrCase()) {
auto enumCase = leaf.getAsEnumAttrCase();
if (enumCase.isStrCase())
return handleConstantAttr(enumCase, enumCase.getSymbol());
// This is an enum case backed by an IntegerAttr. We need to get its value
// to build the constant.
std::string val = std::to_string(enumCase.getValue());
return handleConstantAttr(enumCase, val);
}
LLVM_DEBUG(llvm::dbgs() << "handle argument '" << patArgName << "'\n");
auto argName = symbolInfoMap.getValueAndRangeUse(patArgName);
if (leaf.isUnspecified() || leaf.isOperandMatcher()) {
LLVM_DEBUG(llvm::dbgs() << "replace " << patArgName << " with '" << argName
<< "' (via symbol ref)\n");
return argName;
}
if (leaf.isNativeCodeCall()) {
auto repl = tgfmt(leaf.getNativeCodeTemplate(), &fmtCtx.withSelf(argName));
LLVM_DEBUG(llvm::dbgs() << "replace " << patArgName << " with '" << repl
<< "' (via NativeCodeCall)\n");
return std::string(repl);
}
PrintFatalError(loc, "unhandled case when rewriting op");
}
std::string PatternEmitter::handleReplaceWithNativeCodeCall(DagNode tree,
int depth) {
LLVM_DEBUG(llvm::dbgs() << "handle NativeCodeCall pattern: ");
LLVM_DEBUG(tree.print(llvm::dbgs()));
LLVM_DEBUG(llvm::dbgs() << '\n');
auto fmt = tree.getNativeCodeTemplate();
// TODO: replace formatv arguments with the exact specified args.
SmallVector<std::string, 8> attrs(8);
if (tree.getNumArgs() > 8) {
PrintFatalError(loc,
"unsupported NativeCodeCall replace argument numbers: " +
Twine(tree.getNumArgs()));
}
bool hasLocationDirective;
std::string locToUse;
std::tie(hasLocationDirective, locToUse) = getLocation(tree);
for (int i = 0, e = tree.getNumArgs() - hasLocationDirective; i != e; ++i) {
if (tree.isNestedDagArg(i)) {
attrs[i] = handleResultPattern(tree.getArgAsNestedDag(i), i, depth + 1);
} else {
attrs[i] = handleOpArgument(tree.getArgAsLeaf(i), tree.getArgName(i));
}
LLVM_DEBUG(llvm::dbgs() << "NativeCodeCall argument #" << i
<< " replacement: " << attrs[i] << "\n");
}
return std::string(tgfmt(fmt, &fmtCtx.addSubst("_loc", locToUse), attrs[0],
attrs[1], attrs[2], attrs[3], attrs[4], attrs[5],
attrs[6], attrs[7]));
}
int PatternEmitter::getNodeValueCount(DagNode node) {
if (node.isOperation()) {
// If the op is bound to a symbol in the rewrite rule, query its result
// count from the symbol info map.
auto symbol = node.getSymbol();
if (!symbol.empty()) {
return symbolInfoMap.getStaticValueCount(symbol);
}
// Otherwise this is an unbound op; we will use all its results.
return pattern.getDialectOp(node).getNumResults();
}
// TODO: This considers all NativeCodeCall as returning one
// value. Enhance if multi-value ones are needed.
return 1;
}
std::pair<bool, std::string> PatternEmitter::getLocation(DagNode tree) {
auto numPatArgs = tree.getNumArgs();
if (numPatArgs != 0) {
if (auto lastArg = tree.getArgAsNestedDag(numPatArgs - 1))
if (lastArg.isLocationDirective()) {
return std::make_pair(true, handleLocationDirective(lastArg));
}
}
// If no explicit location is given, use the default, all fused, location.
return std::make_pair(false, "odsLoc");
}
std::string PatternEmitter::handleOpCreation(DagNode tree, int resultIndex,
int depth) {
LLVM_DEBUG(llvm::dbgs() << "create op for pattern: ");
LLVM_DEBUG(tree.print(llvm::dbgs()));
LLVM_DEBUG(llvm::dbgs() << '\n');
Operator &resultOp = tree.getDialectOp(opMap);
auto numOpArgs = resultOp.getNumArgs();
auto numPatArgs = tree.getNumArgs();
bool hasLocationDirective;
std::string locToUse;
std::tie(hasLocationDirective, locToUse) = getLocation(tree);
auto inPattern = numPatArgs - hasLocationDirective;
if (numOpArgs != inPattern) {
PrintFatalError(loc,
formatv("resultant op '{0}' argument number mismatch: "
"{1} in pattern vs. {2} in definition",
resultOp.getOperationName(), inPattern, numOpArgs));
}
// A map to collect all nested DAG child nodes' names, with operand index as
// the key. This includes both bound and unbound child nodes.
ChildNodeIndexNameMap childNodeNames;
// First go through all the child nodes who are nested DAG constructs to
// create ops for them and remember the symbol names for them, so that we can
// use the results in the current node. This happens in a recursive manner.
for (int i = 0, e = resultOp.getNumOperands(); i != e; ++i) {
if (auto child = tree.getArgAsNestedDag(i))
childNodeNames[i] = handleResultPattern(child, i, depth + 1);
}
// The name of the local variable holding this op.
std::string valuePackName;
// The symbol for holding the result of this pattern. Note that the result of
// this pattern is not necessarily the same as the variable created by this
// pattern because we can use `__N` suffix to refer only a specific result if
// the generated op is a multi-result op.
std::string resultValue;
if (tree.getSymbol().empty()) {
// No symbol is explicitly bound to this op in the pattern. Generate a
// unique name.
valuePackName = resultValue = getUniqueSymbol(&resultOp);
} else {
resultValue = std::string(tree.getSymbol());
// Strip the index to get the name for the value pack and use it to name the
// local variable for the op.
valuePackName = std::string(SymbolInfoMap::getValuePackName(resultValue));
}
// Create the local variable for this op.
os << formatv("{0} {1};\n{{\n", resultOp.getQualCppClassName(),
valuePackName);
// Right now ODS don't have general type inference support. Except a few
// special cases listed below, DRR needs to supply types for all results
// when building an op.
bool isSameOperandsAndResultType =
resultOp.getTrait("::mlir::OpTrait::SameOperandsAndResultType");
bool useFirstAttr =
resultOp.getTrait("::mlir::OpTrait::FirstAttrDerivedResultType");
if (isSameOperandsAndResultType || useFirstAttr) {
// We know how to deduce the result type for ops with these traits and we've
// generated builders taking aggregate parameters. Use those builders to
// create the ops.
// First prepare local variables for op arguments used in builder call.
createAggregateLocalVarsForOpArgs(tree, childNodeNames, depth);
// Then create the op.
os.scope("", "\n}\n").os << formatv(
"{0} = rewriter.create<{1}>({2}, tblgen_values, tblgen_attrs);",
valuePackName, resultOp.getQualCppClassName(), locToUse);
return resultValue;
}
bool usePartialResults = valuePackName != resultValue;
if (usePartialResults || depth > 0 || resultIndex < 0) {
// For these cases (broadcastable ops, op results used both as auxiliary
// values and replacement values, ops in nested patterns, auxiliary ops), we
// still need to supply the result types when building the op. But because
// we don't generate a builder automatically with ODS for them, it's the
// developer's responsibility to make sure such a builder (with result type
// deduction ability) exists. We go through the separate-parameter builder
// here given that it's easier for developers to write compared to
// aggregate-parameter builders.
createSeparateLocalVarsForOpArgs(tree, childNodeNames);
os.scope().os << formatv("{0} = rewriter.create<{1}>({2}", valuePackName,
resultOp.getQualCppClassName(), locToUse);
supplyValuesForOpArgs(tree, childNodeNames, depth);
os << "\n );\n}\n";
return resultValue;
}
// If depth == 0 and resultIndex >= 0, it means we are replacing the values
// generated from the source pattern root op. Then we can use the source
// pattern's value types to determine the value type of the generated op
// here.
// First prepare local variables for op arguments used in builder call.
createAggregateLocalVarsForOpArgs(tree, childNodeNames, depth);
// Then prepare the result types. We need to specify the types for all
// results.
os.indent() << formatv("::mlir::SmallVector<::mlir::Type, 4> tblgen_types; "
"(void)tblgen_types;\n");
int numResults = resultOp.getNumResults();
if (numResults != 0) {
for (int i = 0; i < numResults; ++i)
os << formatv("for (auto v: castedOp0.getODSResults({0})) {{\n"
" tblgen_types.push_back(v.getType());\n}\n",
resultIndex + i);
}
os << formatv("{0} = rewriter.create<{1}>({2}, tblgen_types, "
"tblgen_values, tblgen_attrs);\n",
valuePackName, resultOp.getQualCppClassName(), locToUse);
os.unindent() << "}\n";
return resultValue;
}
void PatternEmitter::createSeparateLocalVarsForOpArgs(
DagNode node, ChildNodeIndexNameMap &childNodeNames) {
Operator &resultOp = node.getDialectOp(opMap);
// Now prepare operands used for building this op:
// * If the operand is non-variadic, we create a `Value` local variable.
// * If the operand is variadic, we create a `SmallVector<Value>` local
// variable.
int valueIndex = 0; // An index for uniquing local variable names.
for (int argIndex = 0, e = resultOp.getNumArgs(); argIndex < e; ++argIndex) {
const auto *operand =
resultOp.getArg(argIndex).dyn_cast<NamedTypeConstraint *>();
// We do not need special handling for attributes.
if (!operand)
continue;
raw_indented_ostream::DelimitedScope scope(os);
std::string varName;
if (operand->isVariadic()) {
varName = std::string(formatv("tblgen_values_{0}", valueIndex++));
os << formatv("::mlir::SmallVector<::mlir::Value, 4> {0};\n", varName);
std::string range;
if (node.isNestedDagArg(argIndex)) {
range = childNodeNames[argIndex];
} else {
range = std::string(node.getArgName(argIndex));
}
// Resolve the symbol for all range use so that we have a uniform way of
// capturing the values.
range = symbolInfoMap.getValueAndRangeUse(range);
os << formatv("for (auto v: {0}) {{\n {1}.push_back(v);\n}\n", range,
varName);
} else {
varName = std::string(formatv("tblgen_value_{0}", valueIndex++));
os << formatv("::mlir::Value {0} = ", varName);
if (node.isNestedDagArg(argIndex)) {
os << symbolInfoMap.getValueAndRangeUse(childNodeNames[argIndex]);
} else {
DagLeaf leaf = node.getArgAsLeaf(argIndex);
auto symbol =
symbolInfoMap.getValueAndRangeUse(node.getArgName(argIndex));
if (leaf.isNativeCodeCall()) {
os << std::string(
tgfmt(leaf.getNativeCodeTemplate(), &fmtCtx.withSelf(symbol)));
} else {
os << symbol;
}
}
os << ";\n";
}
// Update to use the newly created local variable for building the op later.
childNodeNames[argIndex] = varName;
}
}
void PatternEmitter::supplyValuesForOpArgs(
DagNode node, const ChildNodeIndexNameMap &childNodeNames, int depth) {
Operator &resultOp = node.getDialectOp(opMap);
for (int argIndex = 0, numOpArgs = resultOp.getNumArgs();
argIndex != numOpArgs; ++argIndex) {
// Start each argument on its own line.
os << ",\n ";
Argument opArg = resultOp.getArg(argIndex);
// Handle the case of operand first.
if (auto *operand = opArg.dyn_cast<NamedTypeConstraint *>()) {
if (!operand->name.empty())
os << "/*" << operand->name << "=*/";
os << childNodeNames.lookup(argIndex);
continue;
}
// The argument in the op definition.
auto opArgName = resultOp.getArgName(argIndex);
if (auto subTree = node.getArgAsNestedDag(argIndex)) {
if (!subTree.isNativeCodeCall())
PrintFatalError(loc, "only NativeCodeCall allowed in nested dag node "
"for creating attribute");
os << formatv("/*{0}=*/{1}", opArgName,
handleReplaceWithNativeCodeCall(subTree, depth));
} else {
auto leaf = node.getArgAsLeaf(argIndex);
// The argument in the result DAG pattern.
auto patArgName = node.getArgName(argIndex);
if (leaf.isConstantAttr() || leaf.isEnumAttrCase()) {
// TODO: Refactor out into map to avoid recomputing these.
if (!opArg.is<NamedAttribute *>())
PrintFatalError(loc, Twine("expected attribute ") + Twine(argIndex));
if (!patArgName.empty())
os << "/*" << patArgName << "=*/";
} else {
os << "/*" << opArgName << "=*/";
}
os << handleOpArgument(leaf, patArgName);
}
}
}
void PatternEmitter::createAggregateLocalVarsForOpArgs(
DagNode node, const ChildNodeIndexNameMap &childNodeNames, int depth) {
Operator &resultOp = node.getDialectOp(opMap);
auto scope = os.scope();
os << formatv("::mlir::SmallVector<::mlir::Value, 4> "
"tblgen_values; (void)tblgen_values;\n");
os << formatv("::mlir::SmallVector<::mlir::NamedAttribute, 4> "
"tblgen_attrs; (void)tblgen_attrs;\n");
const char *addAttrCmd =
"if (auto tmpAttr = {1}) {\n"
" tblgen_attrs.emplace_back(rewriter.getIdentifier(\"{0}\"), "
"tmpAttr);\n}\n";
for (int argIndex = 0, e = resultOp.getNumArgs(); argIndex < e; ++argIndex) {
if (resultOp.getArg(argIndex).is<NamedAttribute *>()) {
// The argument in the op definition.
auto opArgName = resultOp.getArgName(argIndex);
if (auto subTree = node.getArgAsNestedDag(argIndex)) {
if (!subTree.isNativeCodeCall())
PrintFatalError(loc, "only NativeCodeCall allowed in nested dag node "
"for creating attribute");
os << formatv(addAttrCmd, opArgName,
handleReplaceWithNativeCodeCall(subTree, depth + 1));
} else {
auto leaf = node.getArgAsLeaf(argIndex);
// The argument in the result DAG pattern.
auto patArgName = node.getArgName(argIndex);
os << formatv(addAttrCmd, opArgName,
handleOpArgument(leaf, patArgName));
}
continue;
}
const auto *operand =
resultOp.getArg(argIndex).get<NamedTypeConstraint *>();
std::string varName;
if (operand->isVariadic()) {
std::string range;
if (node.isNestedDagArg(argIndex)) {
range = childNodeNames.lookup(argIndex);
} else {
range = std::string(node.getArgName(argIndex));
}
// Resolve the symbol for all range use so that we have a uniform way of
// capturing the values.
range = symbolInfoMap.getValueAndRangeUse(range);
os << formatv("for (auto v: {0}) {{\n tblgen_values.push_back(v);\n}\n",
range);
} else {
os << formatv("tblgen_values.push_back(");
if (node.isNestedDagArg(argIndex)) {
os << symbolInfoMap.getValueAndRangeUse(
childNodeNames.lookup(argIndex));
} else {
DagLeaf leaf = node.getArgAsLeaf(argIndex);
auto symbol =
symbolInfoMap.getValueAndRangeUse(node.getArgName(argIndex));
if (leaf.isNativeCodeCall()) {
os << std::string(
tgfmt(leaf.getNativeCodeTemplate(), &fmtCtx.withSelf(symbol)));
} else {
os << symbol;
}
}
os << ");\n";
}
}
}
static void emitRewriters(const RecordKeeper &recordKeeper, raw_ostream &os) {
emitSourceFileHeader("Rewriters", os);
const auto &patterns = recordKeeper.getAllDerivedDefinitions("Pattern");
auto numPatterns = patterns.size();
// We put the map here because it can be shared among multiple patterns.
RecordOperatorMap recordOpMap;
std::vector<std::string> rewriterNames;
rewriterNames.reserve(numPatterns);
std::string baseRewriterName = "GeneratedConvert";
int rewriterIndex = 0;
for (Record *p : patterns) {
std::string name;
if (p->isAnonymous()) {
// If no name is provided, ensure unique rewriter names simply by
// appending unique suffix.
name = baseRewriterName + llvm::utostr(rewriterIndex++);
} else {
name = std::string(p->getName());
}
LLVM_DEBUG(llvm::dbgs()
<< "=== start generating pattern '" << name << "' ===\n");
PatternEmitter(p, &recordOpMap, os).emit(name);
LLVM_DEBUG(llvm::dbgs()
<< "=== done generating pattern '" << name << "' ===\n");
rewriterNames.push_back(std::move(name));
}
// Emit function to add the generated matchers to the pattern list.
os << "void LLVM_ATTRIBUTE_UNUSED populateWithGenerated(::mlir::MLIRContext "
"*context, ::mlir::OwningRewritePatternList &patterns) {\n";
for (const auto &name : rewriterNames) {
os << " patterns.insert<" << name << ">(context);\n";
}
os << "}\n";
}
static mlir::GenRegistration
genRewriters("gen-rewriters", "Generate pattern rewriters",
[](const RecordKeeper &records, raw_ostream &os) {
emitRewriters(records, os);
return false;
});