6502/kickc
1
0
Fork 0
mirror of https://gitlab.com/camelot/kickc.git synced 2025-02-16 18:30:37 +00:00
Code Issues Projects Releases Wiki Activity

Removed duplicate compiler step.

Browse Source
This commit is contained in:
Jesper Gravgaard 2019-05-22 15:32:42 +02:00
parent 39c4f0d6b4
commit ff7e4bff2a
2 changed files with 0 additions and 76 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
src/main/java/dk/camelot64/kickc/Compiler.java
View File

@ -243,7 +243,6 @@ public class Compiler {
optimizations.add(new Pass2UnaryNotSimplification(program));
optimizations.add(new Pass2AliasElimination(program));
optimizations.add(new Pass2SelfPhiElimination(program));
optimizations.add(new Pass2RedundantPhiElimination(program));
optimizations.add(new Pass2IdenticalPhiElimination(program));
optimizations.add(new Pass2ConditionalJumpSimplification(program));
optimizations.add(new Pass2ConditionalAndOrRewriting(program));

75
src/main/java/dk/camelot64/kickc/passes/Pass2RedundantPhiElimination.java
View File

@ -1,75 +0,0 @@
package dk.camelot64.kickc.passes;
import dk.camelot64.kickc.model.*;
import dk.camelot64.kickc.model.values.LValue;
import dk.camelot64.kickc.model.values.RValue;
import dk.camelot64.kickc.model.values.VariableRef;
import dk.camelot64.kickc.model.statements.StatementPhiBlock;
import java.util.LinkedHashMap;
import java.util.Map;
/** Compiler Pass eliminating redundant phi functions */
public class Pass2RedundantPhiElimination extends Pass2SsaOptimization {
public Pass2RedundantPhiElimination(Program program) {
super(program);
}
/**
* Eliminate alias assignments replacing them with the aliased variable.
*/
@Override
public boolean step() {
final Map<VariableRef, RValue> aliases = findRedundantPhis();
removeAssignments(getGraph(), aliases.keySet());
replaceVariables(aliases);
for(VariableRef var : aliases.keySet()) {
RValue alias = aliases.get(var);
getLog().append("Redundant Phi " + var.toString(getProgram()) + " " + alias.toString(getProgram()));
}
deleteSymbols(getScope(), aliases.keySet());
return aliases.size() > 0;
}
/**
* Find phi variables where all previous symbols are identical.
*
* @return Map from (phi) Variable to the previous value
*/
private Map<VariableRef, RValue> findRedundantPhis() {
final Map<VariableRef, RValue> aliases = new LinkedHashMap<>();
ControlFlowGraphBaseVisitor<Void> visitor = new ControlFlowGraphBaseVisitor<Void>() {
@Override
public Void visitPhiBlock(StatementPhiBlock phi) {
for(StatementPhiBlock.PhiVariable phiVariable : phi.getPhiVariables()) {
boolean found = true;
RValue rValue = null;
for(StatementPhiBlock.PhiRValue phiRValue : phiVariable.getValues()) {
if(rValue == null) {
rValue = phiRValue.getrValue();
} else {
if(!rValue.equals(phiRValue.getrValue())) {
found = false;
break;
}
}
}
if(found) {
VariableRef variable = phiVariable.getVariable();
if(rValue == null) {
rValue = LValue.VOID;
}
aliases.put(variable, rValue);
}
}
return null;
}
};
visitor.visitGraph(getGraph());
return aliases;
}
}