Class MethodModel
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Nested Class Summary
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Method Summary
Modifier and TypeMethodDescriptionvoid
buildBranchGraphs
(Map<Integer, Instruction> pcMap) Here we connect the branch nodes to the instruction that they branch to.void
checkForRecursion
(Set<MethodModel> transitiveCalledMethods) Create a linked list of instructions (from pcHead to pcTail).void
Javac optimizes some branches to avoid goto->goto, branch->goto etc.getLocalVariable
(int _pc, int _index) getName()
boolean
isGetter()
boolean
isNoCL()
boolean
boolean
isSetter()
boolean
boolean
boolean
void
setRequiredPragmas
(Instruction instruction) Look at each instruction for use of long/double or byte writes which require pragmas to be used in the OpenCL sourcetoString()
void
txFormDups
(ExpressionList _expressionList, Instruction _instruction) DUP family of instructions break our stack unwind model (whereby we treat instructions like the oeprands they create/consume).
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Method Details
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isGetter
public boolean isGetter() -
isSetter
public boolean isSetter() -
methodUsesPutfield
public boolean methodUsesPutfield() -
isNoCL
public boolean isNoCL() -
isPrivateMemoryGetter
public boolean isPrivateMemoryGetter() -
getMethod
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getAccessorVariableFieldEntry
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getCalledMethods
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checkForRecursion
- Throws:
AparapiException
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setRequiredPragmas
Look at each instruction for use of long/double or byte writes which require pragmas to be used in the OpenCL source -
requiresDoublePragma
public boolean requiresDoublePragma() -
requiresByteAddressableStorePragma
public boolean requiresByteAddressableStorePragma() -
createListOfInstructions
Create a linked list of instructions (from pcHead to pcTail). Returns a map of int (pc) to Instruction which to allow us to quickly get from a bytecode offset to the appropriate instruction. Note that not all int values from 0 to code.length values will map to a valid instruction, if pcMap.get(n) == null then this implies that 'n' is not the start of an instruction So either pcMap.get(i)== null or pcMap.get(i).getThisPC()==i- Returns:
- Mapinvalid input: '<'Integer, Instruction> the returned pc to Instruction map
- Throws:
ClassParseException
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buildBranchGraphs
Here we connect the branch nodes to the instruction that they branch to.Each branch node contains a 'target' field indended to reference the node that the branch targets. Each instruction also contain four seperate lists of branch nodes that reference it. These lists hold forwardConditional, forwardUnconditional, reverseConditional and revereseUnconditional branches that reference it.
So assuming that we had a branch node at pc offset 100 which represented 'goto 200'.
Following this call the branch node at pc offset 100 will have a 'target' field which actually references the instruction at pc offset 200, and the instruction at pc offset 200 will have the branch node (at 100) added to it's forwardUnconditional list.
- See Also:
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deoptimizeReverseBranches
public void deoptimizeReverseBranches()Javac optimizes some branches to avoid goto->goto, branch->goto etc. This method specifically deals with reverse branches which are the result of such optimisations. -
txFormDups
public void txFormDups(ExpressionList _expressionList, Instruction _instruction) throws ClassParseException DUP family of instructions break our stack unwind model (whereby we treat instructions like the oeprands they create/consume).Here we replace DUP style instructions with a 'mock' instruction which 'clones' the effect of the instruction. This would be invalid to execute but is useful to replace the DUP with a 'pattern' which it simulates. This allows us to later apply transforms to represent the original code.
An example might be the bytecode for the following sequence.
Which results in the following bytecoderesults[10]++; return
First we need to know what the stack will look like before the dup2 is encountered. Using our folding technique we represent the first two instructions inside ()0: aload_0 // reference through 'this' to get 1: getfield // field 'results' which is an array of int 4: bipush 10 // push the array index 6: dup2 // dreaded dup2 we'll come back here 7: iaload // ignore for the moment. 8: iconst_1 9: iadd 10: iastore 11: return
Thegetfield (aload_0 // result in the array field reference on stack bipush 10 // the array index dup2 // dreaded dup2 we'll come back here
dup2
essentially copies the top two elements on the stack. So we emulate this by replacing the dup2 with clones of the instructions which would reinstate the same stack state.So after the
dup2
transform we end up with:-
So carrying on lets look at thegetfield (aload_0) // result in the array field reference on stack bipush 10 // the array index {getfield (aload_0)} // result in the array field reference on stack {bipush 10} // the array index
iaload
which consumes two operands (the index and the array field reference) and creates one (the result of an array access)
So we now havegetfield (aload_0) // result in the array field reference on stack bipush 10 // the array index {getfield (aload_0)} // result in the array field reference on stack {bipush 10} // the array index iaload
And if you are following along thegetfield (aload_0) // result in the array field reference on stack bipush 10 // the array index iaload ({getfield(aload_0), {bipush 10}) // results in the array element on the stack iconst iadd
iadd
will fold the previous two stack entries essentially pushing the result ofresults[10]+1
on the stack.
Then the finalgetfield (aload_0) // result in the array field reference on stack bipush 10 // the array index iadd (iaload ({getfield(aload_0), {bipush 10}, iconst_1) // push of results[10]+1
istore
instruction which consumes 3 stack operands (the field array reference, the index and the value to assign).Which results in
Whereistore (getfield (aload_0), bipush 10, iadd (iaload ({getfield(aload_0), {bipush 10}, iconst_1)) // results[10] = results[10+1]
results[10] = results[10+1]
is the long-hand form of the
results[10]++
and will be transformed by one of the 'inc' transforms to the more familiar form a little later.- Parameters:
_expressionList
-_instruction
-- Throws:
ClassParseException
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getLocalVariableTableEntry
public ClassModel.LocalVariableTableEntry<ClassModel.LocalVariableInfo> getLocalVariableTableEntry() -
getConstantPool
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getLocalVariable
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getSimpleName
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getName
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getReturnType
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getMethodCalls
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getPCHead
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getExprHead
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toString
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