1021 lines
40 KiB
C++
1021 lines
40 KiB
C++
//===- DAGISelMatcherGen.cpp - Matcher generator --------------------------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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#include "DAGISelMatcher.h"
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#include "CodeGenDAGPatterns.h"
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#include "CodeGenRegisters.h"
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#include "llvm/ADT/DenseMap.h"
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#include "llvm/ADT/SmallVector.h"
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#include "llvm/ADT/StringMap.h"
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#include "llvm/TableGen/Error.h"
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#include "llvm/TableGen/Record.h"
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#include <utility>
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using namespace llvm;
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/// getRegisterValueType - Look up and return the ValueType of the specified
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/// register. If the register is a member of multiple register classes which
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/// have different associated types, return MVT::Other.
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static MVT::SimpleValueType getRegisterValueType(Record *R,
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const CodeGenTarget &T) {
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bool FoundRC = false;
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MVT::SimpleValueType VT = MVT::Other;
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const CodeGenRegister *Reg = T.getRegBank().getReg(R);
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for (const auto &RC : T.getRegBank().getRegClasses()) {
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if (!RC.contains(Reg))
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continue;
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if (!FoundRC) {
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FoundRC = true;
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VT = RC.getValueTypeNum(0);
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continue;
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}
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// If this occurs in multiple register classes, they all have to agree.
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assert(VT == RC.getValueTypeNum(0));
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}
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return VT;
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}
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namespace {
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class MatcherGen {
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const PatternToMatch &Pattern;
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const CodeGenDAGPatterns &CGP;
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/// PatWithNoTypes - This is a clone of Pattern.getSrcPattern() that starts
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/// out with all of the types removed. This allows us to insert type checks
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/// as we scan the tree.
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TreePatternNode *PatWithNoTypes;
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/// VariableMap - A map from variable names ('$dst') to the recorded operand
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/// number that they were captured as. These are biased by 1 to make
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/// insertion easier.
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StringMap<unsigned> VariableMap;
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/// This maintains the recorded operand number that OPC_CheckComplexPattern
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/// drops each sub-operand into. We don't want to insert these into
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/// VariableMap because that leads to identity checking if they are
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/// encountered multiple times. Biased by 1 like VariableMap for
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/// consistency.
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StringMap<unsigned> NamedComplexPatternOperands;
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/// NextRecordedOperandNo - As we emit opcodes to record matched values in
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/// the RecordedNodes array, this keeps track of which slot will be next to
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/// record into.
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unsigned NextRecordedOperandNo;
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/// MatchedChainNodes - This maintains the position in the recorded nodes
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/// array of all of the recorded input nodes that have chains.
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SmallVector<unsigned, 2> MatchedChainNodes;
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/// MatchedGlueResultNodes - This maintains the position in the recorded
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/// nodes array of all of the recorded input nodes that have glue results.
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SmallVector<unsigned, 2> MatchedGlueResultNodes;
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/// MatchedComplexPatterns - This maintains a list of all of the
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/// ComplexPatterns that we need to check. The second element of each pair
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/// is the recorded operand number of the input node.
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SmallVector<std::pair<const TreePatternNode*,
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unsigned>, 2> MatchedComplexPatterns;
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/// PhysRegInputs - List list has an entry for each explicitly specified
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/// physreg input to the pattern. The first elt is the Register node, the
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/// second is the recorded slot number the input pattern match saved it in.
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SmallVector<std::pair<Record*, unsigned>, 2> PhysRegInputs;
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/// Matcher - This is the top level of the generated matcher, the result.
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Matcher *TheMatcher;
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/// CurPredicate - As we emit matcher nodes, this points to the latest check
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/// which should have future checks stuck into its Next position.
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Matcher *CurPredicate;
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public:
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MatcherGen(const PatternToMatch &pattern, const CodeGenDAGPatterns &cgp);
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~MatcherGen() {
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delete PatWithNoTypes;
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}
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bool EmitMatcherCode(unsigned Variant);
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void EmitResultCode();
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Matcher *GetMatcher() const { return TheMatcher; }
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private:
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void AddMatcher(Matcher *NewNode);
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void InferPossibleTypes();
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// Matcher Generation.
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void EmitMatchCode(const TreePatternNode *N, TreePatternNode *NodeNoTypes);
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void EmitLeafMatchCode(const TreePatternNode *N);
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void EmitOperatorMatchCode(const TreePatternNode *N,
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TreePatternNode *NodeNoTypes);
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/// If this is the first time a node with unique identifier Name has been
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/// seen, record it. Otherwise, emit a check to make sure this is the same
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/// node. Returns true if this is the first encounter.
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bool recordUniqueNode(std::string Name);
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// Result Code Generation.
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unsigned getNamedArgumentSlot(StringRef Name) {
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unsigned VarMapEntry = VariableMap[Name];
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assert(VarMapEntry != 0 &&
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"Variable referenced but not defined and not caught earlier!");
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return VarMapEntry-1;
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}
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/// GetInstPatternNode - Get the pattern for an instruction.
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const TreePatternNode *GetInstPatternNode(const DAGInstruction &Ins,
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const TreePatternNode *N);
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void EmitResultOperand(const TreePatternNode *N,
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SmallVectorImpl<unsigned> &ResultOps);
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void EmitResultOfNamedOperand(const TreePatternNode *N,
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SmallVectorImpl<unsigned> &ResultOps);
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void EmitResultLeafAsOperand(const TreePatternNode *N,
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SmallVectorImpl<unsigned> &ResultOps);
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void EmitResultInstructionAsOperand(const TreePatternNode *N,
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SmallVectorImpl<unsigned> &ResultOps);
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void EmitResultSDNodeXFormAsOperand(const TreePatternNode *N,
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SmallVectorImpl<unsigned> &ResultOps);
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};
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} // end anon namespace.
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MatcherGen::MatcherGen(const PatternToMatch &pattern,
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const CodeGenDAGPatterns &cgp)
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: Pattern(pattern), CGP(cgp), NextRecordedOperandNo(0),
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TheMatcher(nullptr), CurPredicate(nullptr) {
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// We need to produce the matcher tree for the patterns source pattern. To do
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// this we need to match the structure as well as the types. To do the type
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// matching, we want to figure out the fewest number of type checks we need to
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// emit. For example, if there is only one integer type supported by a
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// target, there should be no type comparisons at all for integer patterns!
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//
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// To figure out the fewest number of type checks needed, clone the pattern,
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// remove the types, then perform type inference on the pattern as a whole.
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// If there are unresolved types, emit an explicit check for those types,
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// apply the type to the tree, then rerun type inference. Iterate until all
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// types are resolved.
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//
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PatWithNoTypes = Pattern.getSrcPattern()->clone();
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PatWithNoTypes->RemoveAllTypes();
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// If there are types that are manifestly known, infer them.
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InferPossibleTypes();
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}
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/// InferPossibleTypes - As we emit the pattern, we end up generating type
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/// checks and applying them to the 'PatWithNoTypes' tree. As we do this, we
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/// want to propagate implied types as far throughout the tree as possible so
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/// that we avoid doing redundant type checks. This does the type propagation.
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void MatcherGen::InferPossibleTypes() {
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// TP - Get *SOME* tree pattern, we don't care which. It is only used for
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// diagnostics, which we know are impossible at this point.
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TreePattern &TP = *CGP.pf_begin()->second;
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bool MadeChange = true;
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while (MadeChange)
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MadeChange = PatWithNoTypes->ApplyTypeConstraints(TP,
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true/*Ignore reg constraints*/);
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}
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/// AddMatcher - Add a matcher node to the current graph we're building.
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void MatcherGen::AddMatcher(Matcher *NewNode) {
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if (CurPredicate)
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CurPredicate->setNext(NewNode);
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else
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TheMatcher = NewNode;
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CurPredicate = NewNode;
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}
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//===----------------------------------------------------------------------===//
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// Pattern Match Generation
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//===----------------------------------------------------------------------===//
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/// EmitLeafMatchCode - Generate matching code for leaf nodes.
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void MatcherGen::EmitLeafMatchCode(const TreePatternNode *N) {
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assert(N->isLeaf() && "Not a leaf?");
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// Direct match against an integer constant.
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if (IntInit *II = dyn_cast<IntInit>(N->getLeafValue())) {
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// If this is the root of the dag we're matching, we emit a redundant opcode
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// check to ensure that this gets folded into the normal top-level
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// OpcodeSwitch.
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if (N == Pattern.getSrcPattern()) {
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const SDNodeInfo &NI = CGP.getSDNodeInfo(CGP.getSDNodeNamed("imm"));
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AddMatcher(new CheckOpcodeMatcher(NI));
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}
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return AddMatcher(new CheckIntegerMatcher(II->getValue()));
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}
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// An UnsetInit represents a named node without any constraints.
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if (N->getLeafValue() == UnsetInit::get()) {
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assert(N->hasName() && "Unnamed ? leaf");
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return;
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}
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DefInit *DI = dyn_cast<DefInit>(N->getLeafValue());
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if (!DI) {
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errs() << "Unknown leaf kind: " << *N << "\n";
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abort();
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}
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Record *LeafRec = DI->getDef();
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// A ValueType leaf node can represent a register when named, or itself when
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// unnamed.
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if (LeafRec->isSubClassOf("ValueType")) {
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// A named ValueType leaf always matches: (add i32:$a, i32:$b).
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if (N->hasName())
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return;
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// An unnamed ValueType as in (sext_inreg GPR:$foo, i8).
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return AddMatcher(new CheckValueTypeMatcher(LeafRec->getName()));
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}
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if (// Handle register references. Nothing to do here, they always match.
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LeafRec->isSubClassOf("RegisterClass") ||
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LeafRec->isSubClassOf("RegisterOperand") ||
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LeafRec->isSubClassOf("PointerLikeRegClass") ||
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LeafRec->isSubClassOf("SubRegIndex") ||
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// Place holder for SRCVALUE nodes. Nothing to do here.
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LeafRec->getName() == "srcvalue")
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return;
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// If we have a physreg reference like (mul gpr:$src, EAX) then we need to
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// record the register
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if (LeafRec->isSubClassOf("Register")) {
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AddMatcher(new RecordMatcher("physreg input "+LeafRec->getName(),
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NextRecordedOperandNo));
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PhysRegInputs.push_back(std::make_pair(LeafRec, NextRecordedOperandNo++));
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return;
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}
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if (LeafRec->isSubClassOf("CondCode"))
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return AddMatcher(new CheckCondCodeMatcher(LeafRec->getName()));
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if (LeafRec->isSubClassOf("ComplexPattern")) {
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// We can't model ComplexPattern uses that don't have their name taken yet.
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// The OPC_CheckComplexPattern operation implicitly records the results.
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if (N->getName().empty()) {
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errs() << "We expect complex pattern uses to have names: " << *N << "\n";
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exit(1);
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}
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// Remember this ComplexPattern so that we can emit it after all the other
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// structural matches are done.
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unsigned InputOperand = VariableMap[N->getName()] - 1;
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MatchedComplexPatterns.push_back(std::make_pair(N, InputOperand));
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return;
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}
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errs() << "Unknown leaf kind: " << *N << "\n";
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abort();
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}
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void MatcherGen::EmitOperatorMatchCode(const TreePatternNode *N,
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TreePatternNode *NodeNoTypes) {
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assert(!N->isLeaf() && "Not an operator?");
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if (N->getOperator()->isSubClassOf("ComplexPattern")) {
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// The "name" of a non-leaf complex pattern (MY_PAT $op1, $op2) is
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// "MY_PAT:op1:op2". We should already have validated that the uses are
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// consistent.
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std::string PatternName = N->getOperator()->getName();
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for (unsigned i = 0; i < N->getNumChildren(); ++i) {
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PatternName += ":";
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PatternName += N->getChild(i)->getName();
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}
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if (recordUniqueNode(PatternName)) {
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auto NodeAndOpNum = std::make_pair(N, NextRecordedOperandNo - 1);
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MatchedComplexPatterns.push_back(NodeAndOpNum);
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}
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return;
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}
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const SDNodeInfo &CInfo = CGP.getSDNodeInfo(N->getOperator());
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// If this is an 'and R, 1234' where the operation is AND/OR and the RHS is
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// a constant without a predicate fn that has more that one bit set, handle
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// this as a special case. This is usually for targets that have special
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// handling of certain large constants (e.g. alpha with it's 8/16/32-bit
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// handling stuff). Using these instructions is often far more efficient
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// than materializing the constant. Unfortunately, both the instcombiner
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// and the dag combiner can often infer that bits are dead, and thus drop
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// them from the mask in the dag. For example, it might turn 'AND X, 255'
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// into 'AND X, 254' if it knows the low bit is set. Emit code that checks
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// to handle this.
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if ((N->getOperator()->getName() == "and" ||
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N->getOperator()->getName() == "or") &&
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N->getChild(1)->isLeaf() && N->getChild(1)->getPredicateFns().empty() &&
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N->getPredicateFns().empty()) {
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if (IntInit *II = dyn_cast<IntInit>(N->getChild(1)->getLeafValue())) {
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if (!isPowerOf2_32(II->getValue())) { // Don't bother with single bits.
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// If this is at the root of the pattern, we emit a redundant
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// CheckOpcode so that the following checks get factored properly under
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// a single opcode check.
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if (N == Pattern.getSrcPattern())
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AddMatcher(new CheckOpcodeMatcher(CInfo));
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// Emit the CheckAndImm/CheckOrImm node.
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if (N->getOperator()->getName() == "and")
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AddMatcher(new CheckAndImmMatcher(II->getValue()));
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else
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AddMatcher(new CheckOrImmMatcher(II->getValue()));
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// Match the LHS of the AND as appropriate.
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AddMatcher(new MoveChildMatcher(0));
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EmitMatchCode(N->getChild(0), NodeNoTypes->getChild(0));
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AddMatcher(new MoveParentMatcher());
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return;
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}
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}
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}
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// Check that the current opcode lines up.
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AddMatcher(new CheckOpcodeMatcher(CInfo));
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// If this node has memory references (i.e. is a load or store), tell the
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// interpreter to capture them in the memref array.
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if (N->NodeHasProperty(SDNPMemOperand, CGP))
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AddMatcher(new RecordMemRefMatcher());
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// If this node has a chain, then the chain is operand #0 is the SDNode, and
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// the child numbers of the node are all offset by one.
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unsigned OpNo = 0;
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if (N->NodeHasProperty(SDNPHasChain, CGP)) {
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// Record the node and remember it in our chained nodes list.
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AddMatcher(new RecordMatcher("'" + N->getOperator()->getName() +
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"' chained node",
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NextRecordedOperandNo));
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// Remember all of the input chains our pattern will match.
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MatchedChainNodes.push_back(NextRecordedOperandNo++);
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// Don't look at the input chain when matching the tree pattern to the
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// SDNode.
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OpNo = 1;
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// If this node is not the root and the subtree underneath it produces a
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// chain, then the result of matching the node is also produce a chain.
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// Beyond that, this means that we're also folding (at least) the root node
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// into the node that produce the chain (for example, matching
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// "(add reg, (load ptr))" as a add_with_memory on X86). This is
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// problematic, if the 'reg' node also uses the load (say, its chain).
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// Graphically:
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//
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// [LD]
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// ^ ^
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// | \ DAG's like cheese.
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// / |
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// / [YY]
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// | ^
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// [XX]--/
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//
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// It would be invalid to fold XX and LD. In this case, folding the two
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// nodes together would induce a cycle in the DAG, making it a 'cyclic DAG'
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// To prevent this, we emit a dynamic check for legality before allowing
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// this to be folded.
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//
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const TreePatternNode *Root = Pattern.getSrcPattern();
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if (N != Root) { // Not the root of the pattern.
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// If there is a node between the root and this node, then we definitely
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// need to emit the check.
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bool NeedCheck = !Root->hasChild(N);
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// If it *is* an immediate child of the root, we can still need a check if
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// the root SDNode has multiple inputs. For us, this means that it is an
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// intrinsic, has multiple operands, or has other inputs like chain or
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// glue).
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if (!NeedCheck) {
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const SDNodeInfo &PInfo = CGP.getSDNodeInfo(Root->getOperator());
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NeedCheck =
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Root->getOperator() == CGP.get_intrinsic_void_sdnode() ||
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Root->getOperator() == CGP.get_intrinsic_w_chain_sdnode() ||
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Root->getOperator() == CGP.get_intrinsic_wo_chain_sdnode() ||
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PInfo.getNumOperands() > 1 ||
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PInfo.hasProperty(SDNPHasChain) ||
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PInfo.hasProperty(SDNPInGlue) ||
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PInfo.hasProperty(SDNPOptInGlue);
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}
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if (NeedCheck)
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AddMatcher(new CheckFoldableChainNodeMatcher());
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}
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}
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// If this node has an output glue and isn't the root, remember it.
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if (N->NodeHasProperty(SDNPOutGlue, CGP) &&
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N != Pattern.getSrcPattern()) {
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// TODO: This redundantly records nodes with both glues and chains.
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// Record the node and remember it in our chained nodes list.
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AddMatcher(new RecordMatcher("'" + N->getOperator()->getName() +
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"' glue output node",
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NextRecordedOperandNo));
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// Remember all of the nodes with output glue our pattern will match.
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MatchedGlueResultNodes.push_back(NextRecordedOperandNo++);
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}
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// If this node is known to have an input glue or if it *might* have an input
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// glue, capture it as the glue input of the pattern.
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if (N->NodeHasProperty(SDNPOptInGlue, CGP) ||
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N->NodeHasProperty(SDNPInGlue, CGP))
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AddMatcher(new CaptureGlueInputMatcher());
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for (unsigned i = 0, e = N->getNumChildren(); i != e; ++i, ++OpNo) {
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// Get the code suitable for matching this child. Move to the child, check
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// it then move back to the parent.
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AddMatcher(new MoveChildMatcher(OpNo));
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EmitMatchCode(N->getChild(i), NodeNoTypes->getChild(i));
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AddMatcher(new MoveParentMatcher());
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}
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}
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bool MatcherGen::recordUniqueNode(std::string Name) {
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unsigned &VarMapEntry = VariableMap[Name];
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if (VarMapEntry == 0) {
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// If it is a named node, we must emit a 'Record' opcode.
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AddMatcher(new RecordMatcher("$" + Name, NextRecordedOperandNo));
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VarMapEntry = ++NextRecordedOperandNo;
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return true;
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}
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// If we get here, this is a second reference to a specific name. Since
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// we already have checked that the first reference is valid, we don't
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// have to recursively match it, just check that it's the same as the
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// previously named thing.
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AddMatcher(new CheckSameMatcher(VarMapEntry-1));
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return false;
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}
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void MatcherGen::EmitMatchCode(const TreePatternNode *N,
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TreePatternNode *NodeNoTypes) {
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// If N and NodeNoTypes don't agree on a type, then this is a case where we
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// need to do a type check. Emit the check, apply the type to NodeNoTypes and
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// reinfer any correlated types.
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SmallVector<unsigned, 2> ResultsToTypeCheck;
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for (unsigned i = 0, e = NodeNoTypes->getNumTypes(); i != e; ++i) {
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|
if (NodeNoTypes->getExtType(i) == N->getExtType(i)) continue;
|
|
NodeNoTypes->setType(i, N->getExtType(i));
|
|
InferPossibleTypes();
|
|
ResultsToTypeCheck.push_back(i);
|
|
}
|
|
|
|
// If this node has a name associated with it, capture it in VariableMap. If
|
|
// we already saw this in the pattern, emit code to verify dagness.
|
|
if (!N->getName().empty())
|
|
if (!recordUniqueNode(N->getName()))
|
|
return;
|
|
|
|
if (N->isLeaf())
|
|
EmitLeafMatchCode(N);
|
|
else
|
|
EmitOperatorMatchCode(N, NodeNoTypes);
|
|
|
|
// If there are node predicates for this node, generate their checks.
|
|
for (unsigned i = 0, e = N->getPredicateFns().size(); i != e; ++i)
|
|
AddMatcher(new CheckPredicateMatcher(N->getPredicateFns()[i]));
|
|
|
|
for (unsigned i = 0, e = ResultsToTypeCheck.size(); i != e; ++i)
|
|
AddMatcher(new CheckTypeMatcher(N->getType(ResultsToTypeCheck[i]),
|
|
ResultsToTypeCheck[i]));
|
|
}
|
|
|
|
/// EmitMatcherCode - Generate the code that matches the predicate of this
|
|
/// pattern for the specified Variant. If the variant is invalid this returns
|
|
/// true and does not generate code, if it is valid, it returns false.
|
|
bool MatcherGen::EmitMatcherCode(unsigned Variant) {
|
|
// If the root of the pattern is a ComplexPattern and if it is specified to
|
|
// match some number of root opcodes, these are considered to be our variants.
|
|
// Depending on which variant we're generating code for, emit the root opcode
|
|
// check.
|
|
if (const ComplexPattern *CP =
|
|
Pattern.getSrcPattern()->getComplexPatternInfo(CGP)) {
|
|
const std::vector<Record*> &OpNodes = CP->getRootNodes();
|
|
assert(!OpNodes.empty() &&"Complex Pattern must specify what it can match");
|
|
if (Variant >= OpNodes.size()) return true;
|
|
|
|
AddMatcher(new CheckOpcodeMatcher(CGP.getSDNodeInfo(OpNodes[Variant])));
|
|
} else {
|
|
if (Variant != 0) return true;
|
|
}
|
|
|
|
// Emit the matcher for the pattern structure and types.
|
|
EmitMatchCode(Pattern.getSrcPattern(), PatWithNoTypes);
|
|
|
|
// If the pattern has a predicate on it (e.g. only enabled when a subtarget
|
|
// feature is around, do the check).
|
|
if (!Pattern.getPredicateCheck().empty())
|
|
AddMatcher(new CheckPatternPredicateMatcher(Pattern.getPredicateCheck()));
|
|
|
|
// Now that we've completed the structural type match, emit any ComplexPattern
|
|
// checks (e.g. addrmode matches). We emit this after the structural match
|
|
// because they are generally more expensive to evaluate and more difficult to
|
|
// factor.
|
|
for (unsigned i = 0, e = MatchedComplexPatterns.size(); i != e; ++i) {
|
|
const TreePatternNode *N = MatchedComplexPatterns[i].first;
|
|
|
|
// Remember where the results of this match get stuck.
|
|
if (N->isLeaf()) {
|
|
NamedComplexPatternOperands[N->getName()] = NextRecordedOperandNo + 1;
|
|
} else {
|
|
unsigned CurOp = NextRecordedOperandNo;
|
|
for (unsigned i = 0; i < N->getNumChildren(); ++i) {
|
|
NamedComplexPatternOperands[N->getChild(i)->getName()] = CurOp + 1;
|
|
CurOp += N->getChild(i)->getNumMIResults(CGP);
|
|
}
|
|
}
|
|
|
|
// Get the slot we recorded the value in from the name on the node.
|
|
unsigned RecNodeEntry = MatchedComplexPatterns[i].second;
|
|
|
|
const ComplexPattern &CP = *N->getComplexPatternInfo(CGP);
|
|
|
|
// Emit a CheckComplexPat operation, which does the match (aborting if it
|
|
// fails) and pushes the matched operands onto the recorded nodes list.
|
|
AddMatcher(new CheckComplexPatMatcher(CP, RecNodeEntry,
|
|
N->getName(), NextRecordedOperandNo));
|
|
|
|
// Record the right number of operands.
|
|
NextRecordedOperandNo += CP.getNumOperands();
|
|
if (CP.hasProperty(SDNPHasChain)) {
|
|
// If the complex pattern has a chain, then we need to keep track of the
|
|
// fact that we just recorded a chain input. The chain input will be
|
|
// matched as the last operand of the predicate if it was successful.
|
|
++NextRecordedOperandNo; // Chained node operand.
|
|
|
|
// It is the last operand recorded.
|
|
assert(NextRecordedOperandNo > 1 &&
|
|
"Should have recorded input/result chains at least!");
|
|
MatchedChainNodes.push_back(NextRecordedOperandNo-1);
|
|
}
|
|
|
|
// TODO: Complex patterns can't have output glues, if they did, we'd want
|
|
// to record them.
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Node Result Generation
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
void MatcherGen::EmitResultOfNamedOperand(const TreePatternNode *N,
|
|
SmallVectorImpl<unsigned> &ResultOps){
|
|
assert(!N->getName().empty() && "Operand not named!");
|
|
|
|
if (unsigned SlotNo = NamedComplexPatternOperands[N->getName()]) {
|
|
// Complex operands have already been completely selected, just find the
|
|
// right slot ant add the arguments directly.
|
|
for (unsigned i = 0; i < N->getNumMIResults(CGP); ++i)
|
|
ResultOps.push_back(SlotNo - 1 + i);
|
|
|
|
return;
|
|
}
|
|
|
|
unsigned SlotNo = getNamedArgumentSlot(N->getName());
|
|
|
|
// If this is an 'imm' or 'fpimm' node, make sure to convert it to the target
|
|
// version of the immediate so that it doesn't get selected due to some other
|
|
// node use.
|
|
if (!N->isLeaf()) {
|
|
StringRef OperatorName = N->getOperator()->getName();
|
|
if (OperatorName == "imm" || OperatorName == "fpimm") {
|
|
AddMatcher(new EmitConvertToTargetMatcher(SlotNo));
|
|
ResultOps.push_back(NextRecordedOperandNo++);
|
|
return;
|
|
}
|
|
}
|
|
|
|
for (unsigned i = 0; i < N->getNumMIResults(CGP); ++i)
|
|
ResultOps.push_back(SlotNo + i);
|
|
}
|
|
|
|
void MatcherGen::EmitResultLeafAsOperand(const TreePatternNode *N,
|
|
SmallVectorImpl<unsigned> &ResultOps) {
|
|
assert(N->isLeaf() && "Must be a leaf");
|
|
|
|
if (IntInit *II = dyn_cast<IntInit>(N->getLeafValue())) {
|
|
AddMatcher(new EmitIntegerMatcher(II->getValue(), N->getType(0)));
|
|
ResultOps.push_back(NextRecordedOperandNo++);
|
|
return;
|
|
}
|
|
|
|
// If this is an explicit register reference, handle it.
|
|
if (DefInit *DI = dyn_cast<DefInit>(N->getLeafValue())) {
|
|
Record *Def = DI->getDef();
|
|
if (Def->isSubClassOf("Register")) {
|
|
const CodeGenRegister *Reg =
|
|
CGP.getTargetInfo().getRegBank().getReg(Def);
|
|
AddMatcher(new EmitRegisterMatcher(Reg, N->getType(0)));
|
|
ResultOps.push_back(NextRecordedOperandNo++);
|
|
return;
|
|
}
|
|
|
|
if (Def->getName() == "zero_reg") {
|
|
AddMatcher(new EmitRegisterMatcher(nullptr, N->getType(0)));
|
|
ResultOps.push_back(NextRecordedOperandNo++);
|
|
return;
|
|
}
|
|
|
|
// Handle a reference to a register class. This is used
|
|
// in COPY_TO_SUBREG instructions.
|
|
if (Def->isSubClassOf("RegisterOperand"))
|
|
Def = Def->getValueAsDef("RegClass");
|
|
if (Def->isSubClassOf("RegisterClass")) {
|
|
std::string Value = getQualifiedName(Def) + "RegClassID";
|
|
AddMatcher(new EmitStringIntegerMatcher(Value, MVT::i32));
|
|
ResultOps.push_back(NextRecordedOperandNo++);
|
|
return;
|
|
}
|
|
|
|
// Handle a subregister index. This is used for INSERT_SUBREG etc.
|
|
if (Def->isSubClassOf("SubRegIndex")) {
|
|
std::string Value = getQualifiedName(Def);
|
|
AddMatcher(new EmitStringIntegerMatcher(Value, MVT::i32));
|
|
ResultOps.push_back(NextRecordedOperandNo++);
|
|
return;
|
|
}
|
|
}
|
|
|
|
errs() << "unhandled leaf node: \n";
|
|
N->dump();
|
|
}
|
|
|
|
/// GetInstPatternNode - Get the pattern for an instruction.
|
|
///
|
|
const TreePatternNode *MatcherGen::
|
|
GetInstPatternNode(const DAGInstruction &Inst, const TreePatternNode *N) {
|
|
const TreePattern *InstPat = Inst.getPattern();
|
|
|
|
// FIXME2?: Assume actual pattern comes before "implicit".
|
|
TreePatternNode *InstPatNode;
|
|
if (InstPat)
|
|
InstPatNode = InstPat->getTree(0);
|
|
else if (/*isRoot*/ N == Pattern.getDstPattern())
|
|
InstPatNode = Pattern.getSrcPattern();
|
|
else
|
|
return nullptr;
|
|
|
|
if (InstPatNode && !InstPatNode->isLeaf() &&
|
|
InstPatNode->getOperator()->getName() == "set")
|
|
InstPatNode = InstPatNode->getChild(InstPatNode->getNumChildren()-1);
|
|
|
|
return InstPatNode;
|
|
}
|
|
|
|
static bool
|
|
mayInstNodeLoadOrStore(const TreePatternNode *N,
|
|
const CodeGenDAGPatterns &CGP) {
|
|
Record *Op = N->getOperator();
|
|
const CodeGenTarget &CGT = CGP.getTargetInfo();
|
|
CodeGenInstruction &II = CGT.getInstruction(Op);
|
|
return II.mayLoad || II.mayStore;
|
|
}
|
|
|
|
static unsigned
|
|
numNodesThatMayLoadOrStore(const TreePatternNode *N,
|
|
const CodeGenDAGPatterns &CGP) {
|
|
if (N->isLeaf())
|
|
return 0;
|
|
|
|
Record *OpRec = N->getOperator();
|
|
if (!OpRec->isSubClassOf("Instruction"))
|
|
return 0;
|
|
|
|
unsigned Count = 0;
|
|
if (mayInstNodeLoadOrStore(N, CGP))
|
|
++Count;
|
|
|
|
for (unsigned i = 0, e = N->getNumChildren(); i != e; ++i)
|
|
Count += numNodesThatMayLoadOrStore(N->getChild(i), CGP);
|
|
|
|
return Count;
|
|
}
|
|
|
|
void MatcherGen::
|
|
EmitResultInstructionAsOperand(const TreePatternNode *N,
|
|
SmallVectorImpl<unsigned> &OutputOps) {
|
|
Record *Op = N->getOperator();
|
|
const CodeGenTarget &CGT = CGP.getTargetInfo();
|
|
CodeGenInstruction &II = CGT.getInstruction(Op);
|
|
const DAGInstruction &Inst = CGP.getInstruction(Op);
|
|
|
|
// If we can, get the pattern for the instruction we're generating. We derive
|
|
// a variety of information from this pattern, such as whether it has a chain.
|
|
//
|
|
// FIXME2: This is extremely dubious for several reasons, not the least of
|
|
// which it gives special status to instructions with patterns that Pat<>
|
|
// nodes can't duplicate.
|
|
const TreePatternNode *InstPatNode = GetInstPatternNode(Inst, N);
|
|
|
|
// NodeHasChain - Whether the instruction node we're creating takes chains.
|
|
bool NodeHasChain = InstPatNode &&
|
|
InstPatNode->TreeHasProperty(SDNPHasChain, CGP);
|
|
|
|
// Instructions which load and store from memory should have a chain,
|
|
// regardless of whether they happen to have an internal pattern saying so.
|
|
if (Pattern.getSrcPattern()->TreeHasProperty(SDNPHasChain, CGP)
|
|
&& (II.hasCtrlDep || II.mayLoad || II.mayStore || II.canFoldAsLoad ||
|
|
II.hasSideEffects))
|
|
NodeHasChain = true;
|
|
|
|
bool isRoot = N == Pattern.getDstPattern();
|
|
|
|
// TreeHasOutGlue - True if this tree has glue.
|
|
bool TreeHasInGlue = false, TreeHasOutGlue = false;
|
|
if (isRoot) {
|
|
const TreePatternNode *SrcPat = Pattern.getSrcPattern();
|
|
TreeHasInGlue = SrcPat->TreeHasProperty(SDNPOptInGlue, CGP) ||
|
|
SrcPat->TreeHasProperty(SDNPInGlue, CGP);
|
|
|
|
// FIXME2: this is checking the entire pattern, not just the node in
|
|
// question, doing this just for the root seems like a total hack.
|
|
TreeHasOutGlue = SrcPat->TreeHasProperty(SDNPOutGlue, CGP);
|
|
}
|
|
|
|
// NumResults - This is the number of results produced by the instruction in
|
|
// the "outs" list.
|
|
unsigned NumResults = Inst.getNumResults();
|
|
|
|
// Number of operands we know the output instruction must have. If it is
|
|
// variadic, we could have more operands.
|
|
unsigned NumFixedOperands = II.Operands.size();
|
|
|
|
SmallVector<unsigned, 8> InstOps;
|
|
|
|
// Loop over all of the fixed operands of the instruction pattern, emitting
|
|
// code to fill them all in. The node 'N' usually has number children equal to
|
|
// the number of input operands of the instruction. However, in cases where
|
|
// there are predicate operands for an instruction, we need to fill in the
|
|
// 'execute always' values. Match up the node operands to the instruction
|
|
// operands to do this.
|
|
unsigned ChildNo = 0;
|
|
for (unsigned InstOpNo = NumResults, e = NumFixedOperands;
|
|
InstOpNo != e; ++InstOpNo) {
|
|
// Determine what to emit for this operand.
|
|
Record *OperandNode = II.Operands[InstOpNo].Rec;
|
|
if (OperandNode->isSubClassOf("OperandWithDefaultOps") &&
|
|
!CGP.getDefaultOperand(OperandNode).DefaultOps.empty()) {
|
|
// This is a predicate or optional def operand; emit the
|
|
// 'default ops' operands.
|
|
const DAGDefaultOperand &DefaultOp
|
|
= CGP.getDefaultOperand(OperandNode);
|
|
for (unsigned i = 0, e = DefaultOp.DefaultOps.size(); i != e; ++i)
|
|
EmitResultOperand(DefaultOp.DefaultOps[i], InstOps);
|
|
continue;
|
|
}
|
|
|
|
// Otherwise this is a normal operand or a predicate operand without
|
|
// 'execute always'; emit it.
|
|
|
|
// For operands with multiple sub-operands we may need to emit
|
|
// multiple child patterns to cover them all. However, ComplexPattern
|
|
// children may themselves emit multiple MI operands.
|
|
unsigned NumSubOps = 1;
|
|
if (OperandNode->isSubClassOf("Operand")) {
|
|
DagInit *MIOpInfo = OperandNode->getValueAsDag("MIOperandInfo");
|
|
if (unsigned NumArgs = MIOpInfo->getNumArgs())
|
|
NumSubOps = NumArgs;
|
|
}
|
|
|
|
unsigned FinalNumOps = InstOps.size() + NumSubOps;
|
|
while (InstOps.size() < FinalNumOps) {
|
|
const TreePatternNode *Child = N->getChild(ChildNo);
|
|
unsigned BeforeAddingNumOps = InstOps.size();
|
|
EmitResultOperand(Child, InstOps);
|
|
assert(InstOps.size() > BeforeAddingNumOps && "Didn't add any operands");
|
|
|
|
// If the operand is an instruction and it produced multiple results, just
|
|
// take the first one.
|
|
if (!Child->isLeaf() && Child->getOperator()->isSubClassOf("Instruction"))
|
|
InstOps.resize(BeforeAddingNumOps+1);
|
|
|
|
++ChildNo;
|
|
}
|
|
}
|
|
|
|
// If this is a variadic output instruction (i.e. REG_SEQUENCE), we can't
|
|
// expand suboperands, use default operands, or other features determined from
|
|
// the CodeGenInstruction after the fixed operands, which were handled
|
|
// above. Emit the remaining instructions implicitly added by the use for
|
|
// variable_ops.
|
|
if (II.Operands.isVariadic) {
|
|
for (unsigned I = ChildNo, E = N->getNumChildren(); I < E; ++I)
|
|
EmitResultOperand(N->getChild(I), InstOps);
|
|
}
|
|
|
|
// If this node has input glue or explicitly specified input physregs, we
|
|
// need to add chained and glued copyfromreg nodes and materialize the glue
|
|
// input.
|
|
if (isRoot && !PhysRegInputs.empty()) {
|
|
// Emit all of the CopyToReg nodes for the input physical registers. These
|
|
// occur in patterns like (mul:i8 AL:i8, GR8:i8:$src).
|
|
for (unsigned i = 0, e = PhysRegInputs.size(); i != e; ++i)
|
|
AddMatcher(new EmitCopyToRegMatcher(PhysRegInputs[i].second,
|
|
PhysRegInputs[i].first));
|
|
// Even if the node has no other glue inputs, the resultant node must be
|
|
// glued to the CopyFromReg nodes we just generated.
|
|
TreeHasInGlue = true;
|
|
}
|
|
|
|
// Result order: node results, chain, glue
|
|
|
|
// Determine the result types.
|
|
SmallVector<MVT::SimpleValueType, 4> ResultVTs;
|
|
for (unsigned i = 0, e = N->getNumTypes(); i != e; ++i)
|
|
ResultVTs.push_back(N->getType(i));
|
|
|
|
// If this is the root instruction of a pattern that has physical registers in
|
|
// its result pattern, add output VTs for them. For example, X86 has:
|
|
// (set AL, (mul ...))
|
|
// This also handles implicit results like:
|
|
// (implicit EFLAGS)
|
|
if (isRoot && !Pattern.getDstRegs().empty()) {
|
|
// If the root came from an implicit def in the instruction handling stuff,
|
|
// don't re-add it.
|
|
Record *HandledReg = nullptr;
|
|
if (II.HasOneImplicitDefWithKnownVT(CGT) != MVT::Other)
|
|
HandledReg = II.ImplicitDefs[0];
|
|
|
|
for (unsigned i = 0; i != Pattern.getDstRegs().size(); ++i) {
|
|
Record *Reg = Pattern.getDstRegs()[i];
|
|
if (!Reg->isSubClassOf("Register") || Reg == HandledReg) continue;
|
|
ResultVTs.push_back(getRegisterValueType(Reg, CGT));
|
|
}
|
|
}
|
|
|
|
// If this is the root of the pattern and the pattern we're matching includes
|
|
// a node that is variadic, mark the generated node as variadic so that it
|
|
// gets the excess operands from the input DAG.
|
|
int NumFixedArityOperands = -1;
|
|
if (isRoot &&
|
|
Pattern.getSrcPattern()->NodeHasProperty(SDNPVariadic, CGP))
|
|
NumFixedArityOperands = Pattern.getSrcPattern()->getNumChildren();
|
|
|
|
// If this is the root node and multiple matched nodes in the input pattern
|
|
// have MemRefs in them, have the interpreter collect them and plop them onto
|
|
// this node. If there is just one node with MemRefs, leave them on that node
|
|
// even if it is not the root.
|
|
//
|
|
// FIXME3: This is actively incorrect for result patterns with multiple
|
|
// memory-referencing instructions.
|
|
bool PatternHasMemOperands =
|
|
Pattern.getSrcPattern()->TreeHasProperty(SDNPMemOperand, CGP);
|
|
|
|
bool NodeHasMemRefs = false;
|
|
if (PatternHasMemOperands) {
|
|
unsigned NumNodesThatLoadOrStore =
|
|
numNodesThatMayLoadOrStore(Pattern.getDstPattern(), CGP);
|
|
bool NodeIsUniqueLoadOrStore = mayInstNodeLoadOrStore(N, CGP) &&
|
|
NumNodesThatLoadOrStore == 1;
|
|
NodeHasMemRefs =
|
|
NodeIsUniqueLoadOrStore || (isRoot && (mayInstNodeLoadOrStore(N, CGP) ||
|
|
NumNodesThatLoadOrStore != 1));
|
|
}
|
|
|
|
assert((!ResultVTs.empty() || TreeHasOutGlue || NodeHasChain) &&
|
|
"Node has no result");
|
|
|
|
AddMatcher(new EmitNodeMatcher(II.Namespace+"::"+II.TheDef->getName(),
|
|
ResultVTs, InstOps,
|
|
NodeHasChain, TreeHasInGlue, TreeHasOutGlue,
|
|
NodeHasMemRefs, NumFixedArityOperands,
|
|
NextRecordedOperandNo));
|
|
|
|
// The non-chain and non-glue results of the newly emitted node get recorded.
|
|
for (unsigned i = 0, e = ResultVTs.size(); i != e; ++i) {
|
|
if (ResultVTs[i] == MVT::Other || ResultVTs[i] == MVT::Glue) break;
|
|
OutputOps.push_back(NextRecordedOperandNo++);
|
|
}
|
|
}
|
|
|
|
void MatcherGen::
|
|
EmitResultSDNodeXFormAsOperand(const TreePatternNode *N,
|
|
SmallVectorImpl<unsigned> &ResultOps) {
|
|
assert(N->getOperator()->isSubClassOf("SDNodeXForm") && "Not SDNodeXForm?");
|
|
|
|
// Emit the operand.
|
|
SmallVector<unsigned, 8> InputOps;
|
|
|
|
// FIXME2: Could easily generalize this to support multiple inputs and outputs
|
|
// to the SDNodeXForm. For now we just support one input and one output like
|
|
// the old instruction selector.
|
|
assert(N->getNumChildren() == 1);
|
|
EmitResultOperand(N->getChild(0), InputOps);
|
|
|
|
// The input currently must have produced exactly one result.
|
|
assert(InputOps.size() == 1 && "Unexpected input to SDNodeXForm");
|
|
|
|
AddMatcher(new EmitNodeXFormMatcher(InputOps[0], N->getOperator()));
|
|
ResultOps.push_back(NextRecordedOperandNo++);
|
|
}
|
|
|
|
void MatcherGen::EmitResultOperand(const TreePatternNode *N,
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SmallVectorImpl<unsigned> &ResultOps) {
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// This is something selected from the pattern we matched.
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if (!N->getName().empty())
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return EmitResultOfNamedOperand(N, ResultOps);
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|
|
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if (N->isLeaf())
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return EmitResultLeafAsOperand(N, ResultOps);
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|
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Record *OpRec = N->getOperator();
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if (OpRec->isSubClassOf("Instruction"))
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return EmitResultInstructionAsOperand(N, ResultOps);
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if (OpRec->isSubClassOf("SDNodeXForm"))
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return EmitResultSDNodeXFormAsOperand(N, ResultOps);
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errs() << "Unknown result node to emit code for: " << *N << '\n';
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PrintFatalError("Unknown node in result pattern!");
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|
}
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|
|
|
void MatcherGen::EmitResultCode() {
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// Patterns that match nodes with (potentially multiple) chain inputs have to
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// merge them together into a token factor. This informs the generated code
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|
// what all the chained nodes are.
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|
if (!MatchedChainNodes.empty())
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|
AddMatcher(new EmitMergeInputChainsMatcher(MatchedChainNodes));
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|
|
|
// Codegen the root of the result pattern, capturing the resulting values.
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|
SmallVector<unsigned, 8> Ops;
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|
EmitResultOperand(Pattern.getDstPattern(), Ops);
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|
|
|
// At this point, we have however many values the result pattern produces.
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|
// However, the input pattern might not need all of these. If there are
|
|
// excess values at the end (such as implicit defs of condition codes etc)
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|
// just lop them off. This doesn't need to worry about glue or chains, just
|
|
// explicit results.
|
|
//
|
|
unsigned NumSrcResults = Pattern.getSrcPattern()->getNumTypes();
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|
|
|
// If the pattern also has (implicit) results, count them as well.
|
|
if (!Pattern.getDstRegs().empty()) {
|
|
// If the root came from an implicit def in the instruction handling stuff,
|
|
// don't re-add it.
|
|
Record *HandledReg = nullptr;
|
|
const TreePatternNode *DstPat = Pattern.getDstPattern();
|
|
if (!DstPat->isLeaf() &&DstPat->getOperator()->isSubClassOf("Instruction")){
|
|
const CodeGenTarget &CGT = CGP.getTargetInfo();
|
|
CodeGenInstruction &II = CGT.getInstruction(DstPat->getOperator());
|
|
|
|
if (II.HasOneImplicitDefWithKnownVT(CGT) != MVT::Other)
|
|
HandledReg = II.ImplicitDefs[0];
|
|
}
|
|
|
|
for (unsigned i = 0; i != Pattern.getDstRegs().size(); ++i) {
|
|
Record *Reg = Pattern.getDstRegs()[i];
|
|
if (!Reg->isSubClassOf("Register") || Reg == HandledReg) continue;
|
|
++NumSrcResults;
|
|
}
|
|
}
|
|
|
|
assert(Ops.size() >= NumSrcResults && "Didn't provide enough results");
|
|
Ops.resize(NumSrcResults);
|
|
|
|
// If the matched pattern covers nodes which define a glue result, emit a node
|
|
// that tells the matcher about them so that it can update their results.
|
|
if (!MatchedGlueResultNodes.empty())
|
|
AddMatcher(new MarkGlueResultsMatcher(MatchedGlueResultNodes));
|
|
|
|
AddMatcher(new CompleteMatchMatcher(Ops, Pattern));
|
|
}
|
|
|
|
|
|
/// ConvertPatternToMatcher - Create the matcher for the specified pattern with
|
|
/// the specified variant. If the variant number is invalid, this returns null.
|
|
Matcher *llvm::ConvertPatternToMatcher(const PatternToMatch &Pattern,
|
|
unsigned Variant,
|
|
const CodeGenDAGPatterns &CGP) {
|
|
MatcherGen Gen(Pattern, CGP);
|
|
|
|
// Generate the code for the matcher.
|
|
if (Gen.EmitMatcherCode(Variant))
|
|
return nullptr;
|
|
|
|
// FIXME2: Kill extra MoveParent commands at the end of the matcher sequence.
|
|
// FIXME2: Split result code out to another table, and make the matcher end
|
|
// with an "Emit <index>" command. This allows result generation stuff to be
|
|
// shared and factored?
|
|
|
|
// If the match succeeds, then we generate Pattern.
|
|
Gen.EmitResultCode();
|
|
|
|
// Unconditional match.
|
|
return Gen.GetMatcher();
|
|
}
|