Make the generated code significantly more memory efficient, by using

SelectNodeTo instead of getTargetNode when possible.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23758 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2005-10-16 01:41:58 +00:00
parent e35d3bb84e
commit 5024d93c8b
2 changed files with 37 additions and 14 deletions

View File

@ -1554,9 +1554,10 @@ void DAGISelEmitter::EmitMatchForPattern(TreePatternNode *N,
unsigned DAGISelEmitter::
CodeGenPatternResult(TreePatternNode *N, unsigned &Ctr,
std::map<std::string,std::string> &VariableMap,
std::ostream &OS) {
std::ostream &OS, bool isRoot) {
// This is something selected from the pattern we matched.
if (!N->getName().empty()) {
assert(!isRoot && "Root of pattern cannot be a leaf!");
std::string &Val = VariableMap[N->getName()];
assert(!Val.empty() &&
"Variable referenced but not defined and not caught earlier!");
@ -1603,12 +1604,33 @@ CodeGenPatternResult(TreePatternNode *N, unsigned &Ctr,
CodeGenInstruction &II = Target.getInstruction(Op->getName());
unsigned ResNo = Ctr++;
if (!isRoot) {
OS << " SDOperand Tmp" << ResNo << " = CurDAG->getTargetNode("
<< II.Namespace << "::" << II.TheDef->getName() << ", MVT::"
<< getEnumName(N->getType());
for (unsigned i = 0, e = Ops.size(); i != e; ++i)
OS << ", Tmp" << Ops[i];
OS << ");\n";
} else {
// If this instruction is the root, and if there is only one use of it,
// use SelectNodeTo instead of getTargetNode to avoid an allocation.
OS << " if (N.Val->hasOneUse()) {\n";
OS << " CurDAG->SelectNodeTo(N.Val, "
<< II.Namespace << "::" << II.TheDef->getName() << ", MVT::"
<< getEnumName(N->getType());
for (unsigned i = 0, e = Ops.size(); i != e; ++i)
OS << ", Tmp" << Ops[i];
OS << ");\n";
OS << " return N;\n";
OS << " } else {\n";
OS << " return CodeGenMap[N] = CurDAG->getTargetNode("
<< II.Namespace << "::" << II.TheDef->getName() << ", MVT::"
<< getEnumName(N->getType());
for (unsigned i = 0, e = Ops.size(); i != e; ++i)
OS << ", Tmp" << Ops[i];
OS << ");\n";
OS << " }\n";
}
return ResNo;
} else if (Op->isSubClassOf("SDNodeXForm")) {
assert(N->getNumChildren() == 1 && "node xform should have one child!");
@ -1617,6 +1639,10 @@ CodeGenPatternResult(TreePatternNode *N, unsigned &Ctr,
unsigned ResNo = Ctr++;
OS << " SDOperand Tmp" << ResNo << " = Transform_" << Op->getName()
<< "(Tmp" << OpVal << ".Val);\n";
if (isRoot) {
OS << " CodeGenMap[N] = Tmp" << ResNo << ";\n";
OS << " return Tmp" << ResNo << ";\n";
}
return ResNo;
} else {
N->dump();
@ -1714,11 +1740,8 @@ void DAGISelEmitter::EmitCodeForPattern(PatternToMatch &Pattern,
} while (InsertOneTypeCheck(Pat, Pattern.first, "N", PatternNo, OS));
unsigned TmpNo = 0;
unsigned Res = CodeGenPatternResult(Pattern.second, TmpNo, VariableMap, OS);
// Add the result to the map if it has multiple uses.
OS << " if (!N.Val->hasOneUse()) CodeGenMap[N] = Tmp" << Res << ";\n";
OS << " return Tmp" << Res << ";\n";
CodeGenPatternResult(Pattern.second, TmpNo,
VariableMap, OS, true /*the root*/);
delete Pat;
OS << " }\n P" << PatternNo << "Fail:\n";

View File

@ -411,7 +411,7 @@ private:
unsigned PatternNo, std::ostream &OS);
unsigned CodeGenPatternResult(TreePatternNode *N, unsigned &Ctr,
std::map<std::string,std::string> &VariableMap,
std::ostream &OS);
std::ostream &OS, bool isRoot = false);
void EmitCodeForPattern(PatternToMatch &Pattern, std::ostream &OS);
void EmitInstructionSelector(std::ostream &OS);
};