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mirror of https://gitlab.com/camelot/kickc.git synced 2024-11-20 02:32:36 +00:00

Minor code clean-up.

This commit is contained in:
jespergravgaard 2021-05-17 08:34:38 +02:00
parent fef4a88204
commit 5de7578bc6
2 changed files with 0 additions and 100 deletions

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@ -247,7 +247,6 @@ public class Pass1GenerateSingleStaticAssignmentForm extends Pass1Base {
/**
* Get all predecessors for a control flow block.
* If the block is the start of an interrupt the @begin is included as a predecessor.
*
* @param block The block to examine
* @return All predecessor blocks

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@ -1,99 +0,0 @@
package dk.camelot64.kickc.passes;
import dk.camelot64.kickc.asm.AsmBasicUpstart;
import dk.camelot64.kickc.asm.AsmChunk;
import dk.camelot64.kickc.asm.AsmInstruction;
import dk.camelot64.kickc.asm.AsmLine;
import dk.camelot64.kickc.model.ControlFlowBlock;
import dk.camelot64.kickc.model.ControlFlowGraph;
import dk.camelot64.kickc.model.Program;
import dk.camelot64.kickc.model.statements.*;
import dk.camelot64.kickc.model.values.LabelRef;
import dk.camelot64.kickc.model.values.ProcedureRef;
import dk.camelot64.kickc.model.values.SymbolRef;
import java.util.ListIterator;
/**
* If the static code section from @begin to @end only has a call to main then modify BasicUpstart to call main directly
*/
public class Pass5SkipBegin extends Pass5AsmOptimization {
public Pass5SkipBegin(Program program) {
super(program);
}
public boolean optimize() {
boolean canSkip = canSkipBegin(getProgram().getGraph());
boolean optimized = false;
if(canSkip) {
// Change BasicUpstart() to call main directly and remove the JSR main
for(AsmChunk chunk : getAsmProgram().getChunks()) {
ListIterator<AsmLine> lineIterator = chunk.getLines().listIterator();
while(lineIterator.hasNext()) {
AsmLine line = lineIterator.next();
if(line instanceof AsmBasicUpstart) {
AsmBasicUpstart basicUpstart = (AsmBasicUpstart) line;
if(!SymbolRef.MAIN_PROC_NAME.equals(basicUpstart.getLabel())) {
basicUpstart.setLabel(SymbolRef.MAIN_PROC_NAME);
optimized = true;
getLog().append("Updating BasicUpstart to call main directly");
}
} else if(line instanceof AsmInstruction) {
AsmInstruction instruction = (AsmInstruction) line;
if(instruction.getCpuOpcode().getMnemonic().equals("jsr")) {
if(instruction.getOperandJumpTarget().equals(SymbolRef.MAIN_PROC_NAME)) {
lineIterator.remove();
optimized = true;
getLog().append("Removing instruction " + line.getAsm());
}
}
}
}
}
}
return optimized;
}
static boolean canSkipBegin(ControlFlowGraph graph) {
ControlFlowBlock beginBlock = graph.getBlock(new LabelRef(SymbolRef.START_PROC_NAME));
return canSkipBegin(beginBlock, graph);
}
/**
* Examines whether the @begin/@end code can be skipped
* This looks through all statements to check that the only one is a call to main()
*
* @param block The block to examine (initially the @begin block)
* @return true if the @begin/@end code can be skipped
*/
private static boolean canSkipBegin(ControlFlowBlock block, ControlFlowGraph graph) {
for(Statement statement : block.getStatements()) {
if(statement instanceof StatementPhiBlock) {
if(((StatementPhiBlock) statement).getPhiVariables().size() > 0) {
return false;
}
} else if(statement instanceof StatementCalling) {
ProcedureRef procedure = ((StatementCalling) statement).getProcedure();
if(!SymbolRef.MAIN_PROC_NAME.equals(procedure.getFullName())) {
return false;
}
} else if(statement instanceof StatementReturn && ((StatementReturn) statement).getValue() == null) {
// Empty return do not prevent skipping begin
} else if(statement instanceof StatementKickAsm) {
// KASM-statements do not prevent skipping begin
} else {
return false;
}
}
if(block.getConditionalSuccessor() != null) {
return false;
}
if(block.getDefaultSuccessor() != null) {
ControlFlowBlock successor = graph.getBlock(block.getDefaultSuccessor());
if(successor != null)
return canSkipBegin(successor, graph);
}
return true;
}
}