use of com.taobao.android.dx.rop.cst.TypedConstant in project atlas by alibaba.
the class ConstCollector method updateConstUses.
/**
* Updates all uses of various consts to use the values in the newly
* assigned registers.
*
* @param newRegs {@code non-null;} mapping between constant and new reg
* @param origRegCount {@code >=0;} original SSA reg count, not including
* newly added constant regs
*/
private void updateConstUses(HashMap<TypedConstant, RegisterSpec> newRegs, int origRegCount) {
/*
* set of constants associated with a local variable; used
* only if COLLECT_ONE_LOCAL is true.
*/
final HashSet<TypedConstant> usedByLocal = new HashSet<TypedConstant>();
final ArrayList<SsaInsn>[] useList = ssaMeth.getUseListCopy();
for (int i = 0; i < origRegCount; i++) {
SsaInsn insn = ssaMeth.getDefinitionForRegister(i);
if (insn == null) {
continue;
}
final RegisterSpec origReg = insn.getResult();
TypeBearer typeBearer = insn.getResult().getTypeBearer();
if (!typeBearer.isConstant())
continue;
TypedConstant cst = (TypedConstant) typeBearer;
final RegisterSpec newReg = newRegs.get(cst);
if (newReg == null) {
continue;
}
if (ssaMeth.isRegALocal(origReg)) {
if (!COLLECT_ONE_LOCAL) {
continue;
} else {
/*
* TODO: If the same local gets the same cst
* multiple times, it would be nice to reuse the
* register.
*/
if (usedByLocal.contains(cst)) {
continue;
} else {
usedByLocal.add(cst);
fixLocalAssignment(origReg, newRegs.get(cst));
}
}
}
// maps an original const register to the new collected register
RegisterMapper mapper = new RegisterMapper() {
@Override
public int getNewRegisterCount() {
return ssaMeth.getRegCount();
}
@Override
public RegisterSpec map(RegisterSpec registerSpec) {
if (registerSpec.getReg() == origReg.getReg()) {
return newReg.withLocalItem(registerSpec.getLocalItem());
}
return registerSpec;
}
};
for (SsaInsn use : useList[origReg.getReg()]) {
if (use.canThrow() && use.getBlock().getSuccessors().cardinality() > 1) {
continue;
}
use.mapSourceRegisters(mapper);
}
}
}
use of com.taobao.android.dx.rop.cst.TypedConstant in project atlas by alibaba.
the class StdAttributeFactory method constantValue.
/**
* Parses a {@code ConstantValue} attribute.
*/
private Attribute constantValue(DirectClassFile cf, int offset, int length, ParseObserver observer) {
if (length != 2) {
return throwBadLength(2);
}
ByteArray bytes = cf.getBytes();
ConstantPool pool = cf.getConstantPool();
int idx = bytes.getUnsignedShort(offset);
TypedConstant cst = (TypedConstant) pool.get(idx);
Attribute result = new AttConstantValue(cst);
if (observer != null) {
observer.parsed(bytes, offset, 2, "value: " + cst);
}
return result;
}
use of com.taobao.android.dx.rop.cst.TypedConstant in project atlas by alibaba.
the class EscapeAnalysis method replaceDef.
/**
* Replaces the instructions that define an array with equivalent registers.
* For each entry in the array, a register is created, initialized to zero.
* A mapping between this register and the corresponding array index is
* added.
*
* @param def {@code non-null;} move result instruction for array
* @param prev {@code non-null;} instruction for instantiating new array
* @param length size of the new array
* @param newRegs {@code non-null;} mapping of array indices to new
* registers to be populated
*/
private void replaceDef(SsaInsn def, SsaInsn prev, int length, ArrayList<RegisterSpec> newRegs) {
Type resultType = def.getResult().getType();
// Create new zeroed out registers for each element in the array
for (int i = 0; i < length; i++) {
Constant newZero = Zeroes.zeroFor(resultType.getComponentType());
TypedConstant typedZero = (TypedConstant) newZero;
RegisterSpec newReg = RegisterSpec.make(ssaMeth.makeNewSsaReg(), typedZero);
newRegs.add(newReg);
insertPlainInsnBefore(def, RegisterSpecList.EMPTY, newReg, RegOps.CONST, newZero);
}
}
use of com.taobao.android.dx.rop.cst.TypedConstant in project atlas by alibaba.
the class ConstCollector method run.
/**
* Applies the optimization.
*/
private void run() {
int regSz = ssaMeth.getRegCount();
ArrayList<TypedConstant> constantList = getConstsSortedByCountUse();
int toCollect = Math.min(constantList.size(), MAX_COLLECTED_CONSTANTS);
SsaBasicBlock start = ssaMeth.getEntryBlock();
// Constant to new register containing the constant
HashMap<TypedConstant, RegisterSpec> newRegs = new HashMap<TypedConstant, RegisterSpec>(toCollect);
for (int i = 0; i < toCollect; i++) {
TypedConstant cst = constantList.get(i);
RegisterSpec result = RegisterSpec.make(ssaMeth.makeNewSsaReg(), cst);
Rop constRop = Rops.opConst(cst);
if (constRop.getBranchingness() == Rop.BRANCH_NONE) {
start.addInsnToHead(new PlainCstInsn(Rops.opConst(cst), SourcePosition.NO_INFO, result, RegisterSpecList.EMPTY, cst));
} else {
// We need two new basic blocks along with the new insn
SsaBasicBlock entryBlock = ssaMeth.getEntryBlock();
SsaBasicBlock successorBlock = entryBlock.getPrimarySuccessor();
// Insert a block containing the const insn.
SsaBasicBlock constBlock = entryBlock.insertNewSuccessor(successorBlock);
constBlock.replaceLastInsn(new ThrowingCstInsn(constRop, SourcePosition.NO_INFO, RegisterSpecList.EMPTY, StdTypeList.EMPTY, cst));
// Insert a block containing the move-result-pseudo insn.
SsaBasicBlock resultBlock = constBlock.insertNewSuccessor(successorBlock);
PlainInsn insn = new PlainInsn(Rops.opMoveResultPseudo(result.getTypeBearer()), SourcePosition.NO_INFO, result, RegisterSpecList.EMPTY);
resultBlock.addInsnToHead(insn);
}
newRegs.put(cst, result);
}
updateConstUses(newRegs, regSz);
}
use of com.taobao.android.dx.rop.cst.TypedConstant in project atlas by alibaba.
the class ConstCollector method getConstsSortedByCountUse.
/**
* Gets all of the collectable constant values used in this method,
* sorted by most used first. Skips non-collectable consts, such as
* non-string object constants
*
* @return {@code non-null;} list of constants in most-to-least used order
*/
private ArrayList<TypedConstant> getConstsSortedByCountUse() {
int regSz = ssaMeth.getRegCount();
final HashMap<TypedConstant, Integer> countUses = new HashMap<TypedConstant, Integer>();
/*
* Each collected constant can be used by just one local
* (used only if COLLECT_ONE_LOCAL is true).
*/
final HashSet<TypedConstant> usedByLocal = new HashSet<TypedConstant>();
// Count how many times each const value is used.
for (int i = 0; i < regSz; i++) {
SsaInsn insn = ssaMeth.getDefinitionForRegister(i);
if (insn == null || insn.getOpcode() == null)
continue;
RegisterSpec result = insn.getResult();
TypeBearer typeBearer = result.getTypeBearer();
if (!typeBearer.isConstant())
continue;
TypedConstant cst = (TypedConstant) typeBearer;
// Find defining instruction for move-result-pseudo instructions
if (insn.getOpcode().getOpcode() == RegOps.MOVE_RESULT_PSEUDO) {
int pred = insn.getBlock().getPredecessors().nextSetBit(0);
ArrayList<SsaInsn> predInsns;
predInsns = ssaMeth.getBlocks().get(pred).getInsns();
insn = predInsns.get(predInsns.size() - 1);
}
if (insn.canThrow()) {
/*
* Don't move anything other than strings -- the risk
* of changing where an exception is thrown is too high.
*/
if (!(cst instanceof CstString) || !COLLECT_STRINGS) {
continue;
}
/*
* We can't move any throwable const whose throw will be
* caught, so don't count them.
*/
if (insn.getBlock().getSuccessors().cardinality() > 1) {
continue;
}
}
/*
* TODO: Might be nice to try and figure out which local
* wins most when collected.
*/
if (ssaMeth.isRegALocal(result)) {
if (!COLLECT_ONE_LOCAL) {
continue;
} else {
if (usedByLocal.contains(cst)) {
// Count one local usage only.
continue;
} else {
usedByLocal.add(cst);
}
}
}
Integer has = countUses.get(cst);
if (has == null) {
countUses.put(cst, 1);
} else {
countUses.put(cst, has + 1);
}
}
// Collect constants that have been reused.
ArrayList<TypedConstant> constantList = new ArrayList<TypedConstant>();
for (Map.Entry<TypedConstant, Integer> entry : countUses.entrySet()) {
if (entry.getValue() > 1) {
constantList.add(entry.getKey());
}
}
// Sort by use, with most used at the beginning of the list.
Collections.sort(constantList, new Comparator<Constant>() {
public int compare(Constant a, Constant b) {
int ret;
ret = countUses.get(b) - countUses.get(a);
if (ret == 0) {
/*
* Provide sorting determinisim for constants with same
* usage count.
*/
ret = a.compareTo(b);
}
return ret;
}
@Override
public boolean equals(Object obj) {
return obj == this;
}
});
return constantList;
}
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