Java Code Examples for com.sun.org.apache.bcel.internal.Constants#ATHROW
The following examples show how to use
com.sun.org.apache.bcel.internal.Constants#ATHROW .
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Example 1
| Source File: MethodGen.java From jdk1.8-source-analysis with Apache License 2.0 | 4 votes |
|
/**
* Computes stack usage of an instruction list by performing control flow analysis.
*
* @return maximum stack depth used by method
*/
public static int getMaxStack(ConstantPoolGen cp, InstructionList il, CodeExceptionGen[] et) {
BranchStack branchTargets = new BranchStack();
/* Initially, populate the branch stack with the exception
* handlers, because these aren't (necessarily) branched to
* explicitly. in each case, the stack will have depth 1,
* containing the exception object.
*/
for (int i = 0; i < et.length; i++) {
InstructionHandle handler_pc = et[i].getHandlerPC();
if (handler_pc != null)
branchTargets.push(handler_pc, 1);
}
int stackDepth = 0, maxStackDepth = 0;
InstructionHandle ih = il.getStart();
while(ih != null) {
Instruction instruction = ih.getInstruction();
short opcode = instruction.getOpcode();
int delta = instruction.produceStack(cp) - instruction.consumeStack(cp);
stackDepth += delta;
if(stackDepth > maxStackDepth)
maxStackDepth = stackDepth;
// choose the next instruction based on whether current is a branch.
if(instruction instanceof BranchInstruction) {
BranchInstruction branch = (BranchInstruction) instruction;
if(instruction instanceof Select) {
// explore all of the select's targets. the default target is handled below.
Select select = (Select) branch;
InstructionHandle[] targets = select.getTargets();
for (int i = 0; i < targets.length; i++)
branchTargets.push(targets[i], stackDepth);
// nothing to fall through to.
ih = null;
} else if(!(branch instanceof IfInstruction)) {
// if an instruction that comes back to following PC,
// push next instruction, with stack depth reduced by 1.
if(opcode == Constants.JSR || opcode == Constants.JSR_W)
branchTargets.push(ih.getNext(), stackDepth - 1);
ih = null;
}
// for all branches, the target of the branch is pushed on the branch stack.
// conditional branches have a fall through case, selects don't, and
// jsr/jsr_w return to the next instruction.
branchTargets.push(branch.getTarget(), stackDepth);
} else {
// check for instructions that terminate the method.
if(opcode == Constants.ATHROW || opcode == Constants.RET ||
(opcode >= Constants.IRETURN && opcode <= Constants.RETURN))
ih = null;
}
// normal case, go to the next instruction.
if(ih != null)
ih = ih.getNext();
// if we have no more instructions, see if there are any deferred branches to explore.
if(ih == null) {
BranchTarget bt = branchTargets.pop();
if (bt != null) {
ih = bt.target;
stackDepth = bt.stackDepth;
}
}
}
return maxStackDepth;
}
Example 2
| Source File: MethodGen.java From TencentKona-8 with GNU General Public License v2.0 | 4 votes |
|
/**
* Computes stack usage of an instruction list by performing control flow analysis.
*
* @return maximum stack depth used by method
*/
public static int getMaxStack(ConstantPoolGen cp, InstructionList il, CodeExceptionGen[] et) {
BranchStack branchTargets = new BranchStack();
/* Initially, populate the branch stack with the exception
* handlers, because these aren't (necessarily) branched to
* explicitly. in each case, the stack will have depth 1,
* containing the exception object.
*/
for (int i = 0; i < et.length; i++) {
InstructionHandle handler_pc = et[i].getHandlerPC();
if (handler_pc != null)
branchTargets.push(handler_pc, 1);
}
int stackDepth = 0, maxStackDepth = 0;
InstructionHandle ih = il.getStart();
while(ih != null) {
Instruction instruction = ih.getInstruction();
short opcode = instruction.getOpcode();
int delta = instruction.produceStack(cp) - instruction.consumeStack(cp);
stackDepth += delta;
if(stackDepth > maxStackDepth)
maxStackDepth = stackDepth;
// choose the next instruction based on whether current is a branch.
if(instruction instanceof BranchInstruction) {
BranchInstruction branch = (BranchInstruction) instruction;
if(instruction instanceof Select) {
// explore all of the select's targets. the default target is handled below.
Select select = (Select) branch;
InstructionHandle[] targets = select.getTargets();
for (int i = 0; i < targets.length; i++)
branchTargets.push(targets[i], stackDepth);
// nothing to fall through to.
ih = null;
} else if(!(branch instanceof IfInstruction)) {
// if an instruction that comes back to following PC,
// push next instruction, with stack depth reduced by 1.
if(opcode == Constants.JSR || opcode == Constants.JSR_W)
branchTargets.push(ih.getNext(), stackDepth - 1);
ih = null;
}
// for all branches, the target of the branch is pushed on the branch stack.
// conditional branches have a fall through case, selects don't, and
// jsr/jsr_w return to the next instruction.
branchTargets.push(branch.getTarget(), stackDepth);
} else {
// check for instructions that terminate the method.
if(opcode == Constants.ATHROW || opcode == Constants.RET ||
(opcode >= Constants.IRETURN && opcode <= Constants.RETURN))
ih = null;
}
// normal case, go to the next instruction.
if(ih != null)
ih = ih.getNext();
// if we have no more instructions, see if there are any deferred branches to explore.
if(ih == null) {
BranchTarget bt = branchTargets.pop();
if (bt != null) {
ih = bt.target;
stackDepth = bt.stackDepth;
}
}
}
return maxStackDepth;
}
Example 3
| Source File: MethodGen.java From jdk8u60 with GNU General Public License v2.0 | 4 votes |
|
/**
* Computes stack usage of an instruction list by performing control flow analysis.
*
* @return maximum stack depth used by method
*/
public static int getMaxStack(ConstantPoolGen cp, InstructionList il, CodeExceptionGen[] et) {
BranchStack branchTargets = new BranchStack();
/* Initially, populate the branch stack with the exception
* handlers, because these aren't (necessarily) branched to
* explicitly. in each case, the stack will have depth 1,
* containing the exception object.
*/
for (int i = 0; i < et.length; i++) {
InstructionHandle handler_pc = et[i].getHandlerPC();
if (handler_pc != null)
branchTargets.push(handler_pc, 1);
}
int stackDepth = 0, maxStackDepth = 0;
InstructionHandle ih = il.getStart();
while(ih != null) {
Instruction instruction = ih.getInstruction();
short opcode = instruction.getOpcode();
int delta = instruction.produceStack(cp) - instruction.consumeStack(cp);
stackDepth += delta;
if(stackDepth > maxStackDepth)
maxStackDepth = stackDepth;
// choose the next instruction based on whether current is a branch.
if(instruction instanceof BranchInstruction) {
BranchInstruction branch = (BranchInstruction) instruction;
if(instruction instanceof Select) {
// explore all of the select's targets. the default target is handled below.
Select select = (Select) branch;
InstructionHandle[] targets = select.getTargets();
for (int i = 0; i < targets.length; i++)
branchTargets.push(targets[i], stackDepth);
// nothing to fall through to.
ih = null;
} else if(!(branch instanceof IfInstruction)) {
// if an instruction that comes back to following PC,
// push next instruction, with stack depth reduced by 1.
if(opcode == Constants.JSR || opcode == Constants.JSR_W)
branchTargets.push(ih.getNext(), stackDepth - 1);
ih = null;
}
// for all branches, the target of the branch is pushed on the branch stack.
// conditional branches have a fall through case, selects don't, and
// jsr/jsr_w return to the next instruction.
branchTargets.push(branch.getTarget(), stackDepth);
} else {
// check for instructions that terminate the method.
if(opcode == Constants.ATHROW || opcode == Constants.RET ||
(opcode >= Constants.IRETURN && opcode <= Constants.RETURN))
ih = null;
}
// normal case, go to the next instruction.
if(ih != null)
ih = ih.getNext();
// if we have no more instructions, see if there are any deferred branches to explore.
if(ih == null) {
BranchTarget bt = branchTargets.pop();
if (bt != null) {
ih = bt.target;
stackDepth = bt.stackDepth;
}
}
}
return maxStackDepth;
}
Example 4
| Source File: MethodGen.java From JDKSourceCode1.8 with MIT License | 4 votes |
|
/**
* Computes stack usage of an instruction list by performing control flow analysis.
*
* @return maximum stack depth used by method
*/
public static int getMaxStack(ConstantPoolGen cp, InstructionList il, CodeExceptionGen[] et) {
BranchStack branchTargets = new BranchStack();
/* Initially, populate the branch stack with the exception
* handlers, because these aren't (necessarily) branched to
* explicitly. in each case, the stack will have depth 1,
* containing the exception object.
*/
for (int i = 0; i < et.length; i++) {
InstructionHandle handler_pc = et[i].getHandlerPC();
if (handler_pc != null)
branchTargets.push(handler_pc, 1);
}
int stackDepth = 0, maxStackDepth = 0;
InstructionHandle ih = il.getStart();
while(ih != null) {
Instruction instruction = ih.getInstruction();
short opcode = instruction.getOpcode();
int delta = instruction.produceStack(cp) - instruction.consumeStack(cp);
stackDepth += delta;
if(stackDepth > maxStackDepth)
maxStackDepth = stackDepth;
// choose the next instruction based on whether current is a branch.
if(instruction instanceof BranchInstruction) {
BranchInstruction branch = (BranchInstruction) instruction;
if(instruction instanceof Select) {
// explore all of the select's targets. the default target is handled below.
Select select = (Select) branch;
InstructionHandle[] targets = select.getTargets();
for (int i = 0; i < targets.length; i++)
branchTargets.push(targets[i], stackDepth);
// nothing to fall through to.
ih = null;
} else if(!(branch instanceof IfInstruction)) {
// if an instruction that comes back to following PC,
// push next instruction, with stack depth reduced by 1.
if(opcode == Constants.JSR || opcode == Constants.JSR_W)
branchTargets.push(ih.getNext(), stackDepth - 1);
ih = null;
}
// for all branches, the target of the branch is pushed on the branch stack.
// conditional branches have a fall through case, selects don't, and
// jsr/jsr_w return to the next instruction.
branchTargets.push(branch.getTarget(), stackDepth);
} else {
// check for instructions that terminate the method.
if(opcode == Constants.ATHROW || opcode == Constants.RET ||
(opcode >= Constants.IRETURN && opcode <= Constants.RETURN))
ih = null;
}
// normal case, go to the next instruction.
if(ih != null)
ih = ih.getNext();
// if we have no more instructions, see if there are any deferred branches to explore.
if(ih == null) {
BranchTarget bt = branchTargets.pop();
if (bt != null) {
ih = bt.target;
stackDepth = bt.stackDepth;
}
}
}
return maxStackDepth;
}
Example 5
| Source File: MethodGen.java From openjdk-jdk8u with GNU General Public License v2.0 | 4 votes |
|
/**
* Computes stack usage of an instruction list by performing control flow analysis.
*
* @return maximum stack depth used by method
*/
public static int getMaxStack(ConstantPoolGen cp, InstructionList il, CodeExceptionGen[] et) {
BranchStack branchTargets = new BranchStack();
/* Initially, populate the branch stack with the exception
* handlers, because these aren't (necessarily) branched to
* explicitly. in each case, the stack will have depth 1,
* containing the exception object.
*/
for (int i = 0; i < et.length; i++) {
InstructionHandle handler_pc = et[i].getHandlerPC();
if (handler_pc != null)
branchTargets.push(handler_pc, 1);
}
int stackDepth = 0, maxStackDepth = 0;
InstructionHandle ih = il.getStart();
while(ih != null) {
Instruction instruction = ih.getInstruction();
short opcode = instruction.getOpcode();
int delta = instruction.produceStack(cp) - instruction.consumeStack(cp);
stackDepth += delta;
if(stackDepth > maxStackDepth)
maxStackDepth = stackDepth;
// choose the next instruction based on whether current is a branch.
if(instruction instanceof BranchInstruction) {
BranchInstruction branch = (BranchInstruction) instruction;
if(instruction instanceof Select) {
// explore all of the select's targets. the default target is handled below.
Select select = (Select) branch;
InstructionHandle[] targets = select.getTargets();
for (int i = 0; i < targets.length; i++)
branchTargets.push(targets[i], stackDepth);
// nothing to fall through to.
ih = null;
} else if(!(branch instanceof IfInstruction)) {
// if an instruction that comes back to following PC,
// push next instruction, with stack depth reduced by 1.
if(opcode == Constants.JSR || opcode == Constants.JSR_W)
branchTargets.push(ih.getNext(), stackDepth - 1);
ih = null;
}
// for all branches, the target of the branch is pushed on the branch stack.
// conditional branches have a fall through case, selects don't, and
// jsr/jsr_w return to the next instruction.
branchTargets.push(branch.getTarget(), stackDepth);
} else {
// check for instructions that terminate the method.
if(opcode == Constants.ATHROW || opcode == Constants.RET ||
(opcode >= Constants.IRETURN && opcode <= Constants.RETURN))
ih = null;
}
// normal case, go to the next instruction.
if(ih != null)
ih = ih.getNext();
// if we have no more instructions, see if there are any deferred branches to explore.
if(ih == null) {
BranchTarget bt = branchTargets.pop();
if (bt != null) {
ih = bt.target;
stackDepth = bt.stackDepth;
}
}
}
return maxStackDepth;
}
Example 6
| Source File: MethodGen.java From openjdk-jdk8u-backup with GNU General Public License v2.0 | 4 votes |
|
/**
* Computes stack usage of an instruction list by performing control flow analysis.
*
* @return maximum stack depth used by method
*/
public static int getMaxStack(ConstantPoolGen cp, InstructionList il, CodeExceptionGen[] et) {
BranchStack branchTargets = new BranchStack();
/* Initially, populate the branch stack with the exception
* handlers, because these aren't (necessarily) branched to
* explicitly. in each case, the stack will have depth 1,
* containing the exception object.
*/
for (int i = 0; i < et.length; i++) {
InstructionHandle handler_pc = et[i].getHandlerPC();
if (handler_pc != null)
branchTargets.push(handler_pc, 1);
}
int stackDepth = 0, maxStackDepth = 0;
InstructionHandle ih = il.getStart();
while(ih != null) {
Instruction instruction = ih.getInstruction();
short opcode = instruction.getOpcode();
int delta = instruction.produceStack(cp) - instruction.consumeStack(cp);
stackDepth += delta;
if(stackDepth > maxStackDepth)
maxStackDepth = stackDepth;
// choose the next instruction based on whether current is a branch.
if(instruction instanceof BranchInstruction) {
BranchInstruction branch = (BranchInstruction) instruction;
if(instruction instanceof Select) {
// explore all of the select's targets. the default target is handled below.
Select select = (Select) branch;
InstructionHandle[] targets = select.getTargets();
for (int i = 0; i < targets.length; i++)
branchTargets.push(targets[i], stackDepth);
// nothing to fall through to.
ih = null;
} else if(!(branch instanceof IfInstruction)) {
// if an instruction that comes back to following PC,
// push next instruction, with stack depth reduced by 1.
if(opcode == Constants.JSR || opcode == Constants.JSR_W)
branchTargets.push(ih.getNext(), stackDepth - 1);
ih = null;
}
// for all branches, the target of the branch is pushed on the branch stack.
// conditional branches have a fall through case, selects don't, and
// jsr/jsr_w return to the next instruction.
branchTargets.push(branch.getTarget(), stackDepth);
} else {
// check for instructions that terminate the method.
if(opcode == Constants.ATHROW || opcode == Constants.RET ||
(opcode >= Constants.IRETURN && opcode <= Constants.RETURN))
ih = null;
}
// normal case, go to the next instruction.
if(ih != null)
ih = ih.getNext();
// if we have no more instructions, see if there are any deferred branches to explore.
if(ih == null) {
BranchTarget bt = branchTargets.pop();
if (bt != null) {
ih = bt.target;
stackDepth = bt.stackDepth;
}
}
}
return maxStackDepth;
}
Example 7
| Source File: MethodGen.java From openjdk-jdk9 with GNU General Public License v2.0 | 4 votes |
|
/**
* Computes stack usage of an instruction list by performing control flow analysis.
*
* @return maximum stack depth used by method
*/
public static int getMaxStack(ConstantPoolGen cp, InstructionList il, CodeExceptionGen[] et) {
BranchStack branchTargets = new BranchStack();
/* Initially, populate the branch stack with the exception
* handlers, because these aren't (necessarily) branched to
* explicitly. in each case, the stack will have depth 1,
* containing the exception object.
*/
for (int i = 0; i < et.length; i++) {
InstructionHandle handler_pc = et[i].getHandlerPC();
if (handler_pc != null)
branchTargets.push(handler_pc, 1);
}
int stackDepth = 0, maxStackDepth = 0;
InstructionHandle ih = il.getStart();
while(ih != null) {
Instruction instruction = ih.getInstruction();
short opcode = instruction.getOpcode();
int delta = instruction.produceStack(cp) - instruction.consumeStack(cp);
stackDepth += delta;
if(stackDepth > maxStackDepth)
maxStackDepth = stackDepth;
// choose the next instruction based on whether current is a branch.
if(instruction instanceof BranchInstruction) {
BranchInstruction branch = (BranchInstruction) instruction;
if(instruction instanceof Select) {
// explore all of the select's targets. the default target is handled below.
Select select = (Select) branch;
InstructionHandle[] targets = select.getTargets();
for (int i = 0; i < targets.length; i++)
branchTargets.push(targets[i], stackDepth);
// nothing to fall through to.
ih = null;
} else if(!(branch instanceof IfInstruction)) {
// if an instruction that comes back to following PC,
// push next instruction, with stack depth reduced by 1.
if(opcode == Constants.JSR || opcode == Constants.JSR_W)
branchTargets.push(ih.getNext(), stackDepth - 1);
ih = null;
}
// for all branches, the target of the branch is pushed on the branch stack.
// conditional branches have a fall through case, selects don't, and
// jsr/jsr_w return to the next instruction.
branchTargets.push(branch.getTarget(), stackDepth);
} else {
// check for instructions that terminate the method.
if(opcode == Constants.ATHROW || opcode == Constants.RET ||
(opcode >= Constants.IRETURN && opcode <= Constants.RETURN))
ih = null;
}
// normal case, go to the next instruction.
if(ih != null)
ih = ih.getNext();
// if we have no more instructions, see if there are any deferred branches to explore.
if(ih == null) {
BranchTarget bt = branchTargets.pop();
if (bt != null) {
ih = bt.target;
stackDepth = bt.stackDepth;
}
}
}
return maxStackDepth;
}
Example 8
| Source File: MethodGen.java From hottub with GNU General Public License v2.0 | 4 votes |
|
/**
* Computes stack usage of an instruction list by performing control flow analysis.
*
* @return maximum stack depth used by method
*/
public static int getMaxStack(ConstantPoolGen cp, InstructionList il, CodeExceptionGen[] et) {
BranchStack branchTargets = new BranchStack();
/* Initially, populate the branch stack with the exception
* handlers, because these aren't (necessarily) branched to
* explicitly. in each case, the stack will have depth 1,
* containing the exception object.
*/
for (int i = 0; i < et.length; i++) {
InstructionHandle handler_pc = et[i].getHandlerPC();
if (handler_pc != null)
branchTargets.push(handler_pc, 1);
}
int stackDepth = 0, maxStackDepth = 0;
InstructionHandle ih = il.getStart();
while(ih != null) {
Instruction instruction = ih.getInstruction();
short opcode = instruction.getOpcode();
int delta = instruction.produceStack(cp) - instruction.consumeStack(cp);
stackDepth += delta;
if(stackDepth > maxStackDepth)
maxStackDepth = stackDepth;
// choose the next instruction based on whether current is a branch.
if(instruction instanceof BranchInstruction) {
BranchInstruction branch = (BranchInstruction) instruction;
if(instruction instanceof Select) {
// explore all of the select's targets. the default target is handled below.
Select select = (Select) branch;
InstructionHandle[] targets = select.getTargets();
for (int i = 0; i < targets.length; i++)
branchTargets.push(targets[i], stackDepth);
// nothing to fall through to.
ih = null;
} else if(!(branch instanceof IfInstruction)) {
// if an instruction that comes back to following PC,
// push next instruction, with stack depth reduced by 1.
if(opcode == Constants.JSR || opcode == Constants.JSR_W)
branchTargets.push(ih.getNext(), stackDepth - 1);
ih = null;
}
// for all branches, the target of the branch is pushed on the branch stack.
// conditional branches have a fall through case, selects don't, and
// jsr/jsr_w return to the next instruction.
branchTargets.push(branch.getTarget(), stackDepth);
} else {
// check for instructions that terminate the method.
if(opcode == Constants.ATHROW || opcode == Constants.RET ||
(opcode >= Constants.IRETURN && opcode <= Constants.RETURN))
ih = null;
}
// normal case, go to the next instruction.
if(ih != null)
ih = ih.getNext();
// if we have no more instructions, see if there are any deferred branches to explore.
if(ih == null) {
BranchTarget bt = branchTargets.pop();
if (bt != null) {
ih = bt.target;
stackDepth = bt.stackDepth;
}
}
}
return maxStackDepth;
}
Example 9
| Source File: MethodGen.java From openjdk-8-source with GNU General Public License v2.0 | 4 votes |
|
/**
* Computes stack usage of an instruction list by performing control flow analysis.
*
* @return maximum stack depth used by method
*/
public static int getMaxStack(ConstantPoolGen cp, InstructionList il, CodeExceptionGen[] et) {
BranchStack branchTargets = new BranchStack();
/* Initially, populate the branch stack with the exception
* handlers, because these aren't (necessarily) branched to
* explicitly. in each case, the stack will have depth 1,
* containing the exception object.
*/
for (int i = 0; i < et.length; i++) {
InstructionHandle handler_pc = et[i].getHandlerPC();
if (handler_pc != null)
branchTargets.push(handler_pc, 1);
}
int stackDepth = 0, maxStackDepth = 0;
InstructionHandle ih = il.getStart();
while(ih != null) {
Instruction instruction = ih.getInstruction();
short opcode = instruction.getOpcode();
int delta = instruction.produceStack(cp) - instruction.consumeStack(cp);
stackDepth += delta;
if(stackDepth > maxStackDepth)
maxStackDepth = stackDepth;
// choose the next instruction based on whether current is a branch.
if(instruction instanceof BranchInstruction) {
BranchInstruction branch = (BranchInstruction) instruction;
if(instruction instanceof Select) {
// explore all of the select's targets. the default target is handled below.
Select select = (Select) branch;
InstructionHandle[] targets = select.getTargets();
for (int i = 0; i < targets.length; i++)
branchTargets.push(targets[i], stackDepth);
// nothing to fall through to.
ih = null;
} else if(!(branch instanceof IfInstruction)) {
// if an instruction that comes back to following PC,
// push next instruction, with stack depth reduced by 1.
if(opcode == Constants.JSR || opcode == Constants.JSR_W)
branchTargets.push(ih.getNext(), stackDepth - 1);
ih = null;
}
// for all branches, the target of the branch is pushed on the branch stack.
// conditional branches have a fall through case, selects don't, and
// jsr/jsr_w return to the next instruction.
branchTargets.push(branch.getTarget(), stackDepth);
} else {
// check for instructions that terminate the method.
if(opcode == Constants.ATHROW || opcode == Constants.RET ||
(opcode >= Constants.IRETURN && opcode <= Constants.RETURN))
ih = null;
}
// normal case, go to the next instruction.
if(ih != null)
ih = ih.getNext();
// if we have no more instructions, see if there are any deferred branches to explore.
if(ih == null) {
BranchTarget bt = branchTargets.pop();
if (bt != null) {
ih = bt.target;
stackDepth = bt.stackDepth;
}
}
}
return maxStackDepth;
}
Example 10
| Source File: MethodGen.java From openjdk-8 with GNU General Public License v2.0 | 4 votes |
|
/**
* Computes stack usage of an instruction list by performing control flow analysis.
*
* @return maximum stack depth used by method
*/
public static int getMaxStack(ConstantPoolGen cp, InstructionList il, CodeExceptionGen[] et) {
BranchStack branchTargets = new BranchStack();
/* Initially, populate the branch stack with the exception
* handlers, because these aren't (necessarily) branched to
* explicitly. in each case, the stack will have depth 1,
* containing the exception object.
*/
for (int i = 0; i < et.length; i++) {
InstructionHandle handler_pc = et[i].getHandlerPC();
if (handler_pc != null)
branchTargets.push(handler_pc, 1);
}
int stackDepth = 0, maxStackDepth = 0;
InstructionHandle ih = il.getStart();
while(ih != null) {
Instruction instruction = ih.getInstruction();
short opcode = instruction.getOpcode();
int delta = instruction.produceStack(cp) - instruction.consumeStack(cp);
stackDepth += delta;
if(stackDepth > maxStackDepth)
maxStackDepth = stackDepth;
// choose the next instruction based on whether current is a branch.
if(instruction instanceof BranchInstruction) {
BranchInstruction branch = (BranchInstruction) instruction;
if(instruction instanceof Select) {
// explore all of the select's targets. the default target is handled below.
Select select = (Select) branch;
InstructionHandle[] targets = select.getTargets();
for (int i = 0; i < targets.length; i++)
branchTargets.push(targets[i], stackDepth);
// nothing to fall through to.
ih = null;
} else if(!(branch instanceof IfInstruction)) {
// if an instruction that comes back to following PC,
// push next instruction, with stack depth reduced by 1.
if(opcode == Constants.JSR || opcode == Constants.JSR_W)
branchTargets.push(ih.getNext(), stackDepth - 1);
ih = null;
}
// for all branches, the target of the branch is pushed on the branch stack.
// conditional branches have a fall through case, selects don't, and
// jsr/jsr_w return to the next instruction.
branchTargets.push(branch.getTarget(), stackDepth);
} else {
// check for instructions that terminate the method.
if(opcode == Constants.ATHROW || opcode == Constants.RET ||
(opcode >= Constants.IRETURN && opcode <= Constants.RETURN))
ih = null;
}
// normal case, go to the next instruction.
if(ih != null)
ih = ih.getNext();
// if we have no more instructions, see if there are any deferred branches to explore.
if(ih == null) {
BranchTarget bt = branchTargets.pop();
if (bt != null) {
ih = bt.target;
stackDepth = bt.stackDepth;
}
}
}
return maxStackDepth;
}
