coins.ir.hir
クラス SimplifyHir

java.lang.Object
  |
  +--coins.ir.hir.SimplifyHir

public class SimplifyHir

extends java.lang.Object

SimplifyHir: This class simplifies HIR by deleting labeled statements with null statement body if the label is not explicitly refered, in order to suppress the generation of useless basic blocks in converting HIR to LIR. If HIR is changed by this class, finishHir() is called in this class so that HIR may keep consistency. This is invoked just before HIR-to-LIR conversion by the compiler driver. This does nothing if the compiler option -coins:hirOpt=noSimplify is specified and pForceSimplify is false. It is not recommended to invoke this before HIR transformations such as optimization and parallelization because the simplified HIR may be unsuitablbe for such HIR transformations. Description of simplifications If-statement: (if (condition) (labeledStmt (thenLabel) thenPartStatement) (labeledStmt (elseLabel) ) (labeledStmt (endLabel) )) --> (if (condition) (labeledStmt (thenLabel) thenPartStatement) (labeledStmt (endLabel) )) (if (condition) (labeledStmt (thenLabel) ) (labeledStmt (elseLabel) elsePartStatement) (labeledStmt (endLabel) )) --> (if (condition) (labeledStmt (elseLabel) elsePartStatement) (labeledStmt (endLabel) )) Loop-statement: The general form of a loop statement is (loop LoopInitPart ConditionalInitPart -- usually null (labeledStmt (loopBackLabel) (expStmt ... )) -- loop-start conditionPart (labeledStmt (loopBodyLabel) (block ... -- loop body part (labeledStmt (loopStepLabel) )) (expStmt ... ) -- loop-end condition (labeledStmt (loopEndLabel) )) If loop-start condition is null, remove loopBodylabel by changing (labeledStmt (loopBodyLabel) (block ...)) to (block ... ). If loopStepLabel is not explicitly refered (that is, the loop does not contain continue-statement), then (labeledStmt (loopStepLabel) ) is deleted. Switch-statement: The simplification of switch-statement is covered by the simplification of labeled statement. Labeled-satement: Simplify LabeledStmt having LabeledStmt as its body: (labelDef (lab1) (labelDef (lab2) stmtBody)) --> (labelDef (lab1 lab2) stmtBody) (labelDef (lab1) (block (labelDef (lab2) stmtBody) .... )) --> (labelDef (lab1 lab2) (block stmtBody .... )) After above simplifications, change statements with multiple labels to statements with single label and rewrite HIR nodes refering erazed labels to the remaining label, that is, (labelDef (lab1 lab2 ... labn) stmtBody) --> (labelDef (lab1) stmtBody) and change references to lab2, ..., labn to lab1.

フィールドの概要

(パッケージプライベート) boolean	fChanged
(パッケージプライベート) int	fDbgLevel
(パッケージプライベート) java.util.ArrayList	fLabelDefToBeDeleted
(パッケージプライベート) java.util.ArrayList	fLabeledStmt
(パッケージプライベート) java.util.ArrayList	fLabelRef
(パッケージプライベート) java.util.HashMap	fReplaceLabel
(パッケージプライベート) boolean	fSomeSubpChanged
(パッケージプライベート) java.util.ArrayList	fStmtToBeDeleted
(パッケージプライベート) java.util.ArrayList	fStmtWithMultipleLabels
(パッケージプライベート) Subp	fSubp
(パッケージプライベート) HirRoot	hirRoot
(パッケージプライベート) IoRoot	ioRoot

コンストラクタの概要

SimplifyHir(HirRoot pHirRoot, boolean pForceSimplify)

メソッドの概要

(パッケージプライベート) void	deleteIfNull(LabeledStmt pStmt)
void	deleteUnusedLabelsOfIfStmt(IfStmt pIfStmt)
void	deleteUnusedLabelsOfLoopStmt(LoopStmt pLoopStmt)
void	recordLabelRefOfSwitchStmt(SwitchStmt pSwitchStmt)
(パッケージプライベート) boolean	shouldHaveLabel(LabeledStmt pStmt)
void	simplifyHir(Subp pSubp)

クラス java.lang.Object から継承したメソッド

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

フィールドの詳細

hirRoot

HirRoot hirRoot

ioRoot

IoRoot ioRoot

fSubp

Subp fSubp

fLabelDefToBeDeleted

java.util.ArrayList fLabelDefToBeDeleted

fStmtToBeDeleted

java.util.ArrayList fStmtToBeDeleted

fLabeledStmt

java.util.ArrayList fLabeledStmt

fStmtWithMultipleLabels

java.util.ArrayList fStmtWithMultipleLabels

fLabelRef

java.util.ArrayList fLabelRef

fReplaceLabel

java.util.HashMap fReplaceLabel

fChanged

boolean fChanged

fSomeSubpChanged

boolean fSomeSubpChanged

fDbgLevel

int fDbgLevel

コンストラクタの詳細

SimplifyHir

public SimplifyHir(HirRoot pHirRoot,
                   boolean pForceSimplify)

メソッドの詳細

simplifyHir

public void simplifyHir(Subp pSubp)

deleteUnusedLabelsOfIfStmt

public void deleteUnusedLabelsOfIfStmt(IfStmt pIfStmt)

deleteUnusedLabelsOfLoopStmt

public void deleteUnusedLabelsOfLoopStmt(LoopStmt pLoopStmt)

recordLabelRefOfSwitchStmt

public void recordLabelRefOfSwitchStmt(SwitchStmt pSwitchStmt)

shouldHaveLabel

boolean shouldHaveLabel(LabeledStmt pStmt)

deleteIfNull

void deleteIfNull(LabeledStmt pStmt)