CodeGenerator

java.lang.Object
- EDU.purdue.cs.bloat.tree.TreeVisitor
- - EDU.purdue.cs.bloat.codegen.CodeGenerator

All Implemented Interfaces:

Opcode
```
public class CodeGenerator
extends TreeVisitor
implements Opcode
```
CodeGenerator performs some final optimizations and is used (via a visitor) to generate bytecode for the contents of a control flow graph.

See Also:

FlowGraph

Field Summary

Fields
Modifier and Type	Field	Description
`static boolean`	`DB_OPT_STACK`
`static boolean`	`DEBUG`
`protected MethodEditor`	`method`
`protected Block`	`next`
`boolean`	`nowb`
`static boolean`	`OPT_STACK`	Use information about placement of local variables to eliminate loads and stores in favor of stack manipulations
`protected java.util.Map`	`postponedInstructions`
`protected int`	`stackHeight`
`static boolean`	`USE_PERSISTENT`
`protected java.util.Set`	`visited`

Fields inherited from interface EDU.purdue.cs.bloat.editor.Opcode
opc_aaload, opc_aastore, opc_aconst_null, opc_aload, opc_aload_0, opc_aload_1, opc_aload_2, opc_aload_3, opc_anewarray, opc_areturn, opc_arraylength, opc_astore, opc_astore_0, opc_astore_1, opc_astore_2, opc_astore_3, opc_aswizzle, opc_aswrange, opc_athrow, opc_aupdate, opc_baload, opc_bastore, opc_bipush, opc_breakpoint, opc_caload, opc_castore, opc_checkcast, opc_d2f, opc_d2i, opc_d2l, opc_dadd, opc_daload, opc_dastore, opc_dcmpg, opc_dcmpl, opc_dconst_0, opc_dconst_1, opc_ddiv, opc_dload, opc_dload_0, opc_dload_1, opc_dload_2, opc_dload_3, opc_dmul, opc_dneg, opc_drem, opc_dreturn, opc_dstore, opc_dstore_0, opc_dstore_1, opc_dstore_2, opc_dstore_3, opc_dsub, opc_dup, opc_dup_x1, opc_dup_x2, opc_dup2, opc_dup2_x1, opc_dup2_x2, opc_f2d, opc_f2i, opc_f2l, opc_fadd, opc_faload, opc_fastore, opc_fcmpg, opc_fcmpl, opc_fconst_0, opc_fconst_1, opc_fconst_2, opc_fdiv, opc_fload, opc_fload_0, opc_fload_1, opc_fload_2, opc_fload_3, opc_fmul, opc_fneg, opc_frem, opc_freturn, opc_fstore, opc_fstore_0, opc_fstore_1, opc_fstore_2, opc_fstore_3, opc_fsub, opc_getfield, opc_getstatic, opc_goto, opc_goto_w, opc_i2b, opc_i2c, opc_i2d, opc_i2f, opc_i2l, opc_i2s, opc_iadd, opc_iaload, opc_iand, opc_iastore, opc_iconst_0, opc_iconst_1, opc_iconst_2, opc_iconst_3, opc_iconst_4, opc_iconst_5, opc_iconst_m1, opc_idiv, opc_if_acmpeq, opc_if_acmpne, opc_if_icmpeq, opc_if_icmpge, opc_if_icmpgt, opc_if_icmple, opc_if_icmplt, opc_if_icmpne, opc_ifeq, opc_ifge, opc_ifgt, opc_ifle, opc_iflt, opc_ifne, opc_ifnonnull, opc_ifnull, opc_iinc, opc_iload, opc_iload_0, opc_iload_1, opc_iload_2, opc_iload_3, opc_imul, opc_ineg, opc_instanceof, opc_invokeinterface, opc_invokespecial, opc_invokestatic, opc_invokevirtual, opc_ior, opc_irem, opc_ireturn, opc_ishl, opc_ishr, opc_istore, opc_istore_0, opc_istore_1, opc_istore_2, opc_istore_3, opc_isub, opc_iushr, opc_ixor, opc_jsr, opc_jsr_w, opc_l2d, opc_l2f, opc_l2i, opc_ladd, opc_laload, opc_land, opc_lastore, opc_lcmp, opc_lconst_0, opc_lconst_1, opc_ldc, opc_ldc_w, opc_ldc2_w, opc_ldiv, opc_lload, opc_lload_0, opc_lload_1, opc_lload_2, opc_lload_3, opc_lmul, opc_lneg, opc_lookupswitch, opc_lor, opc_lrem, opc_lreturn, opc_lshl, opc_lshr, opc_lstore, opc_lstore_0, opc_lstore_1, opc_lstore_2, opc_lstore_3, opc_lsub, opc_lushr, opc_lxor, opc_monitorenter, opc_monitorexit, opc_multianewarray, opc_new, opc_newarray, opc_nop, opc_pop, opc_pop2, opc_putfield, opc_putfield_nowb, opc_putstatic, opc_putstatic_nowb, opc_rc, opc_ret, opc_return, opc_saload, opc_sastore, opc_sipush, opc_supdate, opc_swap, opc_tableswitch, opc_wide, opc_xxxunusedxxx, opcNames, opcSize, opcx_aaload, opcx_aastore, opcx_aload, opcx_areturn, opcx_arraylength, opcx_astore, opcx_aswizzle, opcx_aswrange, opcx_athrow, opcx_aupdate, opcx_baload, opcx_bastore, opcx_caload, opcx_castore, opcx_checkcast, opcx_d2f, opcx_d2i, opcx_d2l, opcx_dadd, opcx_daload, opcx_dastore, opcx_dcmpg, opcx_dcmpl, opcx_ddiv, opcx_dload, opcx_dmul, opcx_dneg, opcx_drem, opcx_dreturn, opcx_dstore, opcx_dsub, opcx_dup, opcx_dup_x1, opcx_dup_x2, opcx_dup2, opcx_dup2_x1, opcx_dup2_x2, opcx_f2d, opcx_f2i, opcx_f2l, opcx_fadd, opcx_faload, opcx_fastore, opcx_fcmpg, opcx_fcmpl, opcx_fdiv, opcx_fload, opcx_fmul, opcx_fneg, opcx_frem, opcx_freturn, opcx_fstore, opcx_fsub, opcx_getfield, opcx_getstatic, opcx_goto, opcx_i2b, opcx_i2c, opcx_i2d, opcx_i2f, opcx_i2l, opcx_i2s, opcx_iadd, opcx_iaload, opcx_iand, opcx_iastore, opcx_idiv, opcx_if_acmpeq, opcx_if_acmpne, opcx_if_icmpeq, opcx_if_icmpge, opcx_if_icmpgt, opcx_if_icmple, opcx_if_icmplt, opcx_if_icmpne, opcx_ifeq, opcx_ifge, opcx_ifgt, opcx_ifle, opcx_iflt, opcx_ifne, opcx_ifnonnull, opcx_ifnull, opcx_iinc, opcx_iload, opcx_imul, opcx_ineg, opcx_instanceof, opcx_invokeinterface, opcx_invokespecial, opcx_invokestatic, opcx_invokevirtual, opcx_ior, opcx_irem, opcx_ireturn, opcx_ishl, opcx_ishr, opcx_istore, opcx_isub, opcx_iushr, opcx_ixor, opcx_jsr, opcx_l2d, opcx_l2f, opcx_l2i, opcx_ladd, opcx_laload, opcx_land, opcx_lastore, opcx_lcmp, opcx_ldc, opcx_ldiv, opcx_lload, opcx_lmul, opcx_lneg, opcx_lor, opcx_lrem, opcx_lreturn, opcx_lshl, opcx_lshr, opcx_lstore, opcx_lsub, opcx_lushr, opcx_lxor, opcx_monitorenter, opcx_monitorexit, opcx_multianewarray, opcx_new, opcx_newarray, opcx_nop, opcx_pop, opcx_pop2, opcx_putfield, opcx_putfield_nowb, opcx_putstatic, opcx_putstatic_nowb, opcx_rc, opcx_ret, opcx_return, opcx_saload, opcx_sastore, opcx_supdate, opcx_swap, opcx_switch, opcXMap, VARIABLE

Fields inherited from class EDU.purdue.cs.bloat.tree.TreeVisitor
FORWARD, REVERSE

Constructor Summary

Constructors
Constructor Description

CodeGenerator(MethodEditor method)
Constructor.

Constructors
Constructor	Description
`CodeGenerator(MethodEditor method)`	Constructor.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`allocReturnAddresses(FlowGraph cfg, RegisterAllocator alloc)`	Allocate "registers" (LocalVariables) for the return addresses for each subroutine in the method.
`protected Stmt`	`createStore(VarExpr target, Expr source)`	Returns an ExprStmt that contains a store of the source into the target.
`protected Stmt`	`createUndefinedStore(VarExpr target)`	Create a ExprStmt that initializes a target variable to a default value based on the type of the target.
`void`	`replacePhis(FlowGraph cfg)`	Replace PhiStmts with copies that accomplish what the PhiStmts represent.
`void`	`simplifyControlFlow(FlowGraph cfg)`	Simplifies the control flow of a method by changing jump and return statements into gotos where appropriate.
`void`	`visitAddressStoreStmt(AddressStoreStmt stmt)`
`void`	`visitArithExpr(ArithExpr expr)`
`void`	`visitArrayLengthExpr(ArrayLengthExpr expr)`
`void`	`visitArrayRefExpr(ArrayRefExpr expr)`
`void`	`visitCallMethodExpr(CallMethodExpr expr)`
`void`	`visitCallStaticExpr(CallStaticExpr expr)`
`void`	`visitCastExpr(CastExpr expr)`
`void`	`visitCatchExpr(CatchExpr expr)`
`void`	`visitConstantExpr(ConstantExpr expr)`
`void`	`visitDefExpr(DefExpr expr)`
`void`	`visitExpr(Expr expr)`
`void`	`visitExprStmt(ExprStmt stmt)`
`void`	`visitFieldExpr(FieldExpr expr)`
`void`	`visitFlowGraph(FlowGraph cfg)`	Visits the nodes in the method's control flow graph and ensures that information about the method's basic blocks is consistent and correct.
`void`	`visitGotoStmt(GotoStmt stmt)`
`void`	`visitIfCmpStmt(IfCmpStmt stmt)`
`void`	`visitIfZeroStmt(IfZeroStmt stmt)`
`void`	`visitInitStmt(InitStmt stmt)`
`void`	`visitInstanceOfExpr(InstanceOfExpr expr)`
`void`	`visitJsrStmt(JsrStmt stmt)`
`void`	`visitLabelStmt(LabelStmt stmt)`
`void`	`visitLocalExpr(LocalExpr expr)`
`void`	`visitMonitorStmt(MonitorStmt stmt)`
`void`	`visitNegExpr(NegExpr expr)`
`void`	`visitNewArrayExpr(NewArrayExpr expr)`
`void`	`visitNewExpr(NewExpr expr)`
`void`	`visitNewMultiArrayExpr(NewMultiArrayExpr expr)`
`void`	`visitPhiStmt(PhiStmt stmt)`
`void`	`visitRCExpr(RCExpr expr)`
`void`	`visitRetStmt(RetStmt stmt)`
`void`	`visitReturnAddressExpr(ReturnAddressExpr expr)`
`void`	`visitReturnExprStmt(ReturnExprStmt stmt)`
`void`	`visitReturnStmt(ReturnStmt stmt)`
`void`	`visitSCStmt(SCStmt stmt)`
`void`	`visitShiftExpr(ShiftExpr expr)`
`void`	`visitSRStmt(SRStmt stmt)`
`void`	`visitStackExpr(StackExpr expr)`
`void`	`visitStackManipStmt(StackManipStmt stmt)`
`void`	`visitStaticFieldExpr(StaticFieldExpr expr)`
`void`	`visitStoreExpr(StoreExpr expr)`
`void`	`visitSwitchStmt(SwitchStmt stmt)`
`void`	`visitThrowStmt(ThrowStmt stmt)`
`void`	`visitUCExpr(UCExpr expr)`
`void`	`visitZeroCheckExpr(ZeroCheckExpr expr)`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from class EDU.purdue.cs.bloat.tree.TreeVisitor
direction, forward, prune, reverse, setPrune, visitBlock, visitCallExpr, visitCheckExpr, visitIfStmt, visitMemExpr, visitMemRefExpr, visitNode, visitPhiCatchStmt, visitPhiJoinStmt, visitStmt, visitTree, visitVarExpr

- Field Detail
  - DEBUG
```
public static boolean DEBUG
```
  - USE_PERSISTENT
```
public static boolean USE_PERSISTENT
```
  - OPT_STACK
```
public static boolean OPT_STACK
```
    Use information about placement of local variables to eliminate loads and stores in favor of stack manipulations
  - DB_OPT_STACK
```
public static boolean DB_OPT_STACK
```
  - method
```
protected MethodEditor method
```
  - visited
```
protected java.util.Set visited
```
  - postponedInstructions
```
protected java.util.Map postponedInstructions
```
  - next
```
protected Block next
```
  - stackHeight
```
protected int stackHeight
```
  - nowb
```
public boolean nowb
```
- Constructor Detail
  - CodeGenerator
```
public CodeGenerator(MethodEditor method)
```
    Constructor.
    
    Parameters:
    
    method - The method for which bytecode is generated.
- Method Detail
  - visitFlowGraph
```
public void visitFlowGraph(FlowGraph cfg)
```
    Visits the nodes in the method's control flow graph and ensures that information about the method's basic blocks is consistent and correct.
    
    Overrides:
    
    visitFlowGraph in class TreeVisitor
    
    Parameters:
    
    cfg - The control flow graph associated with this method.
  - simplifyControlFlow
```
public void simplifyControlFlow(FlowGraph cfg)
```
    Simplifies the control flow of a method by changing jump and return statements into gotos where appropriate.
  - replacePhis
```
public void replacePhis(FlowGraph cfg)
```
    Replace PhiStmts with copies that accomplish what the PhiStmts represent. Then remove the PhiStmts from the control flow graph.
  - allocReturnAddresses
```
public void allocReturnAddresses(FlowGraph cfg,
                                 RegisterAllocator alloc)
```
    Allocate "registers" (LocalVariables) for the return addresses for each subroutine in the method.
    
    Parameters:
    
    cfg - Control flow graph for the method
    
    alloc - Allocation (and information about) the local variables in the method.
    
    See Also:
    
    LocalVariable, LocalExpr
  - createUndefinedStore
```
protected Stmt createUndefinedStore(VarExpr target)
```
    Create a ExprStmt that initializes a target variable to a default value based on the type of the target.
  - createStore
```
protected Stmt createStore(VarExpr target,
                           Expr source)
```
    Returns an ExprStmt that contains a store of the source into the target.
  - visitExpr
```
public void visitExpr(Expr expr)
```
    Overrides:
    
    visitExpr in class TreeVisitor
  - visitExprStmt
```
public void visitExprStmt(ExprStmt stmt)
```
    Overrides:
    
    visitExprStmt in class TreeVisitor
  - visitInitStmt
```
public void visitInitStmt(InitStmt stmt)
```
    Overrides:
    
    visitInitStmt in class TreeVisitor
  - visitGotoStmt
```
public void visitGotoStmt(GotoStmt stmt)
```
    Overrides:
    
    visitGotoStmt in class TreeVisitor
  - visitIfCmpStmt
```
public void visitIfCmpStmt(IfCmpStmt stmt)
```
    Overrides:
    
    visitIfCmpStmt in class TreeVisitor
  - visitIfZeroStmt
```
public void visitIfZeroStmt(IfZeroStmt stmt)
```
    Overrides:
    
    visitIfZeroStmt in class TreeVisitor
  - visitLabelStmt
```
public void visitLabelStmt(LabelStmt stmt)
```
    Overrides:
    
    visitLabelStmt in class TreeVisitor
  - visitMonitorStmt
```
public void visitMonitorStmt(MonitorStmt stmt)
```
    Overrides:
    
    visitMonitorStmt in class TreeVisitor
  - visitPhiStmt
```
public void visitPhiStmt(PhiStmt stmt)
```
    Overrides:
    
    visitPhiStmt in class TreeVisitor
  - visitRCExpr
```
public void visitRCExpr(RCExpr expr)
```
    Overrides:
    
    visitRCExpr in class TreeVisitor
  - visitUCExpr
```
public void visitUCExpr(UCExpr expr)
```
    Overrides:
    
    visitUCExpr in class TreeVisitor
  - visitRetStmt
```
public void visitRetStmt(RetStmt stmt)
```
    Overrides:
    
    visitRetStmt in class TreeVisitor
  - visitReturnExprStmt
```
public void visitReturnExprStmt(ReturnExprStmt stmt)
```
    Overrides:
    
    visitReturnExprStmt in class TreeVisitor
  - visitReturnStmt
```
public void visitReturnStmt(ReturnStmt stmt)
```
    Overrides:
    
    visitReturnStmt in class TreeVisitor
  - visitStoreExpr
```
public void visitStoreExpr(StoreExpr expr)
```
    Overrides:
    
    visitStoreExpr in class TreeVisitor
  - visitAddressStoreStmt
```
public void visitAddressStoreStmt(AddressStoreStmt stmt)
```
    Overrides:
    
    visitAddressStoreStmt in class TreeVisitor
  - visitJsrStmt
```
public void visitJsrStmt(JsrStmt stmt)
```
    Overrides:
    
    visitJsrStmt in class TreeVisitor
  - visitSwitchStmt
```
public void visitSwitchStmt(SwitchStmt stmt)
```
    Overrides:
    
    visitSwitchStmt in class TreeVisitor
  - visitStackManipStmt
```
public void visitStackManipStmt(StackManipStmt stmt)
```
    Overrides:
    
    visitStackManipStmt in class TreeVisitor
  - visitThrowStmt
```
public void visitThrowStmt(ThrowStmt stmt)
```
    Overrides:
    
    visitThrowStmt in class TreeVisitor
  - visitSCStmt
```
public void visitSCStmt(SCStmt stmt)
```
    Overrides:
    
    visitSCStmt in class TreeVisitor
  - visitSRStmt
```
public void visitSRStmt(SRStmt stmt)
```
    Overrides:
    
    visitSRStmt in class TreeVisitor
  - visitArithExpr
```
public void visitArithExpr(ArithExpr expr)
```
    Overrides:
    
    visitArithExpr in class TreeVisitor
  - visitArrayLengthExpr
```
public void visitArrayLengthExpr(ArrayLengthExpr expr)
```
    Overrides:
    
    visitArrayLengthExpr in class TreeVisitor
  - visitArrayRefExpr
```
public void visitArrayRefExpr(ArrayRefExpr expr)
```
    Overrides:
    
    visitArrayRefExpr in class TreeVisitor
  - visitCallMethodExpr
```
public void visitCallMethodExpr(CallMethodExpr expr)
```
    Overrides:
    
    visitCallMethodExpr in class TreeVisitor
  - visitCallStaticExpr
```
public void visitCallStaticExpr(CallStaticExpr expr)
```
    Overrides:
    
    visitCallStaticExpr in class TreeVisitor
  - visitCastExpr
```
public void visitCastExpr(CastExpr expr)
```
    Overrides:
    
    visitCastExpr in class TreeVisitor
  - visitConstantExpr
```
public void visitConstantExpr(ConstantExpr expr)
```
    Overrides:
    
    visitConstantExpr in class TreeVisitor
  - visitFieldExpr
```
public void visitFieldExpr(FieldExpr expr)
```
    Overrides:
    
    visitFieldExpr in class TreeVisitor
  - visitInstanceOfExpr
```
public void visitInstanceOfExpr(InstanceOfExpr expr)
```
    Overrides:
    
    visitInstanceOfExpr in class TreeVisitor
  - visitLocalExpr
```
public void visitLocalExpr(LocalExpr expr)
```
    Overrides:
    
    visitLocalExpr in class TreeVisitor
  - visitNegExpr
```
public void visitNegExpr(NegExpr expr)
```
    Overrides:
    
    visitNegExpr in class TreeVisitor
  - visitNewArrayExpr
```
public void visitNewArrayExpr(NewArrayExpr expr)
```
    Overrides:
    
    visitNewArrayExpr in class TreeVisitor
  - visitNewExpr
```
public void visitNewExpr(NewExpr expr)
```
    Overrides:
    
    visitNewExpr in class TreeVisitor
  - visitNewMultiArrayExpr
```
public void visitNewMultiArrayExpr(NewMultiArrayExpr expr)
```
    Overrides:
    
    visitNewMultiArrayExpr in class TreeVisitor
  - visitReturnAddressExpr
```
public void visitReturnAddressExpr(ReturnAddressExpr expr)
```
    Overrides:
    
    visitReturnAddressExpr in class TreeVisitor
  - visitShiftExpr
```
public void visitShiftExpr(ShiftExpr expr)
```
    Overrides:
    
    visitShiftExpr in class TreeVisitor
  - visitDefExpr
```
public void visitDefExpr(DefExpr expr)
```
    Overrides:
    
    visitDefExpr in class TreeVisitor
  - visitCatchExpr
```
public void visitCatchExpr(CatchExpr expr)
```
    Overrides:
    
    visitCatchExpr in class TreeVisitor
  - visitStackExpr
```
public void visitStackExpr(StackExpr expr)
```
    Overrides:
    
    visitStackExpr in class TreeVisitor
  - visitStaticFieldExpr
```
public void visitStaticFieldExpr(StaticFieldExpr expr)
```
    Overrides:
    
    visitStaticFieldExpr in class TreeVisitor
  - visitZeroCheckExpr
```
public void visitZeroCheckExpr(ZeroCheckExpr expr)
```
    Overrides:
    
    visitZeroCheckExpr in class TreeVisitor

Class CodeGenerator

Field Summary

Fields inherited from interface EDU.purdue.cs.bloat.editor.Opcode

Fields inherited from class EDU.purdue.cs.bloat.tree.TreeVisitor

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from class EDU.purdue.cs.bloat.tree.TreeVisitor

Field Detail

DEBUG

USE_PERSISTENT

OPT_STACK

DB_OPT_STACK

method

visited

postponedInstructions

next

stackHeight

nowb

Constructor Detail

CodeGenerator

Method Detail

visitFlowGraph

simplifyControlFlow

replacePhis

allocReturnAddresses

createUndefinedStore

createStore

visitExpr

visitExprStmt

visitInitStmt

visitGotoStmt

visitIfCmpStmt

visitIfZeroStmt

visitLabelStmt

visitMonitorStmt

visitPhiStmt

visitRCExpr

visitUCExpr

visitRetStmt

visitReturnExprStmt

visitReturnStmt

visitStoreExpr

visitAddressStoreStmt

visitJsrStmt

visitSwitchStmt

visitStackManipStmt

visitThrowStmt

visitSCStmt

visitSRStmt

visitArithExpr

visitArrayLengthExpr

visitArrayRefExpr

visitCallMethodExpr

visitCallStaticExpr

visitCastExpr

visitConstantExpr

visitFieldExpr

visitInstanceOfExpr

visitLocalExpr

visitNegExpr

visitNewArrayExpr

visitNewExpr

visitNewMultiArrayExpr

visitReturnAddressExpr

visitShiftExpr

visitDefExpr

visitCatchExpr

visitStackExpr

visitStaticFieldExpr

visitZeroCheckExpr