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diff --git a/contrib/llvm/utils/TableGen/DAGISelEmitter.cpp b/contrib/llvm/utils/TableGen/DAGISelEmitter.cpp
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+//===- DAGISelEmitter.cpp - Generate an instruction selector --------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This tablegen backend emits a DAG instruction selector.
+//
+//===----------------------------------------------------------------------===//
+
+#include "DAGISelEmitter.h"
+#include "DAGISelMatcher.h"
+#include "Record.h"
+#include "llvm/Support/Debug.h"
+using namespace llvm;
+
+//===----------------------------------------------------------------------===//
+// DAGISelEmitter Helper methods
+//
+
+/// getResultPatternCost - Compute the number of instructions for this pattern.
+/// This is a temporary hack. We should really include the instruction
+/// latencies in this calculation.
+static unsigned getResultPatternCost(TreePatternNode *P,
+ CodeGenDAGPatterns &CGP) {
+ if (P->isLeaf()) return 0;
+
+ unsigned Cost = 0;
+ Record *Op = P->getOperator();
+ if (Op->isSubClassOf("Instruction")) {
+ Cost++;
+ CodeGenInstruction &II = CGP.getTargetInfo().getInstruction(Op);
+ if (II.usesCustomInserter)
+ Cost += 10;
+ }
+ for (unsigned i = 0, e = P->getNumChildren(); i != e; ++i)
+ Cost += getResultPatternCost(P->getChild(i), CGP);
+ return Cost;
+}
+
+/// getResultPatternCodeSize - Compute the code size of instructions for this
+/// pattern.
+static unsigned getResultPatternSize(TreePatternNode *P,
+ CodeGenDAGPatterns &CGP) {
+ if (P->isLeaf()) return 0;
+
+ unsigned Cost = 0;
+ Record *Op = P->getOperator();
+ if (Op->isSubClassOf("Instruction")) {
+ Cost += Op->getValueAsInt("CodeSize");
+ }
+ for (unsigned i = 0, e = P->getNumChildren(); i != e; ++i)
+ Cost += getResultPatternSize(P->getChild(i), CGP);
+ return Cost;
+}
+
+//===----------------------------------------------------------------------===//
+// Predicate emitter implementation.
+//
+
+void DAGISelEmitter::EmitPredicateFunctions(raw_ostream &OS) {
+ OS << "\n// Predicate functions.\n";
+
+ // Walk the pattern fragments, adding them to a map, which sorts them by
+ // name.
+ typedef std::map<std::string, std::pair<Record*, TreePattern*> > PFsByNameTy;
+ PFsByNameTy PFsByName;
+
+ for (CodeGenDAGPatterns::pf_iterator I = CGP.pf_begin(), E = CGP.pf_end();
+ I != E; ++I)
+ PFsByName.insert(std::make_pair(I->first->getName(), *I));
+
+
+ for (PFsByNameTy::iterator I = PFsByName.begin(), E = PFsByName.end();
+ I != E; ++I) {
+ Record *PatFragRecord = I->second.first;// Record that derives from PatFrag.
+ TreePattern *P = I->second.second;
+
+ // If there is a code init for this fragment, emit the predicate code.
+ std::string Code = PatFragRecord->getValueAsCode("Predicate");
+ if (Code.empty()) continue;
+
+ if (P->getOnlyTree()->isLeaf())
+ OS << "inline bool Predicate_" << PatFragRecord->getName()
+ << "(SDNode *N) const {\n";
+ else {
+ std::string ClassName =
+ CGP.getSDNodeInfo(P->getOnlyTree()->getOperator()).getSDClassName();
+ const char *C2 = ClassName == "SDNode" ? "N" : "inN";
+
+ OS << "inline bool Predicate_" << PatFragRecord->getName()
+ << "(SDNode *" << C2 << ") const {\n";
+ if (ClassName != "SDNode")
+ OS << " " << ClassName << " *N = cast<" << ClassName << ">(inN);\n";
+ }
+ OS << Code << "\n}\n";
+ }
+
+ OS << "\n\n";
+}
+
+namespace {
+// PatternSortingPredicate - return true if we prefer to match LHS before RHS.
+// In particular, we want to match maximal patterns first and lowest cost within
+// a particular complexity first.
+struct PatternSortingPredicate {
+ PatternSortingPredicate(CodeGenDAGPatterns &cgp) : CGP(cgp) {}
+ CodeGenDAGPatterns &CGP;
+
+ bool operator()(const PatternToMatch *LHS, const PatternToMatch *RHS) {
+ const TreePatternNode *LHSSrc = LHS->getSrcPattern();
+ const TreePatternNode *RHSSrc = RHS->getSrcPattern();
+
+ if (LHSSrc->getNumTypes() != 0 && RHSSrc->getNumTypes() != 0 &&
+ LHSSrc->getType(0) != RHSSrc->getType(0)) {
+ MVT::SimpleValueType V1 = LHSSrc->getType(0), V2 = RHSSrc->getType(0);
+ if (MVT(V1).isVector() != MVT(V2).isVector())
+ return MVT(V2).isVector();
+
+ if (MVT(V1).isFloatingPoint() != MVT(V2).isFloatingPoint())
+ return MVT(V2).isFloatingPoint();
+ }
+
+ // Otherwise, if the patterns might both match, sort based on complexity,
+ // which means that we prefer to match patterns that cover more nodes in the
+ // input over nodes that cover fewer.
+ unsigned LHSSize = LHS->getPatternComplexity(CGP);
+ unsigned RHSSize = RHS->getPatternComplexity(CGP);
+ if (LHSSize > RHSSize) return true; // LHS -> bigger -> less cost
+ if (LHSSize < RHSSize) return false;
+
+ // If the patterns have equal complexity, compare generated instruction cost
+ unsigned LHSCost = getResultPatternCost(LHS->getDstPattern(), CGP);
+ unsigned RHSCost = getResultPatternCost(RHS->getDstPattern(), CGP);
+ if (LHSCost < RHSCost) return true;
+ if (LHSCost > RHSCost) return false;
+
+ unsigned LHSPatSize = getResultPatternSize(LHS->getDstPattern(), CGP);
+ unsigned RHSPatSize = getResultPatternSize(RHS->getDstPattern(), CGP);
+ if (LHSPatSize < RHSPatSize) return true;
+ if (LHSPatSize > RHSPatSize) return false;
+
+ // Sort based on the UID of the pattern, giving us a deterministic ordering
+ // if all other sorting conditions fail.
+ assert(LHS == RHS || LHS->ID != RHS->ID);
+ return LHS->ID < RHS->ID;
+ }
+};
+}
+
+
+void DAGISelEmitter::run(raw_ostream &OS) {
+ EmitSourceFileHeader("DAG Instruction Selector for the " +
+ CGP.getTargetInfo().getName() + " target", OS);
+
+ OS << "// *** NOTE: This file is #included into the middle of the target\n"
+ << "// *** instruction selector class. These functions are really "
+ << "methods.\n\n";
+
+ DEBUG(errs() << "\n\nALL PATTERNS TO MATCH:\n\n";
+ for (CodeGenDAGPatterns::ptm_iterator I = CGP.ptm_begin(),
+ E = CGP.ptm_end(); I != E; ++I) {
+ errs() << "PATTERN: "; I->getSrcPattern()->dump();
+ errs() << "\nRESULT: "; I->getDstPattern()->dump();
+ errs() << "\n";
+ });
+
+ // FIXME: These are being used by hand written code, gross.
+ EmitPredicateFunctions(OS);
+
+ // Add all the patterns to a temporary list so we can sort them.
+ std::vector<const PatternToMatch*> Patterns;
+ for (CodeGenDAGPatterns::ptm_iterator I = CGP.ptm_begin(), E = CGP.ptm_end();
+ I != E; ++I)
+ Patterns.push_back(&*I);
+
+ // We want to process the matches in order of minimal cost. Sort the patterns
+ // so the least cost one is at the start.
+ std::sort(Patterns.begin(), Patterns.end(), PatternSortingPredicate(CGP));
+
+
+ // Convert each variant of each pattern into a Matcher.
+ std::vector<Matcher*> PatternMatchers;
+ for (unsigned i = 0, e = Patterns.size(); i != e; ++i) {
+ for (unsigned Variant = 0; ; ++Variant) {
+ if (Matcher *M = ConvertPatternToMatcher(*Patterns[i], Variant, CGP))
+ PatternMatchers.push_back(M);
+ else
+ break;
+ }
+ }
+
+ Matcher *TheMatcher = new ScopeMatcher(&PatternMatchers[0],
+ PatternMatchers.size());
+
+ TheMatcher = OptimizeMatcher(TheMatcher, CGP);
+ //Matcher->dump();
+ EmitMatcherTable(TheMatcher, CGP, OS);
+ delete TheMatcher;
+}
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