Examples with RegisterSpec com.taobao.android.dx.rop.code.RegisterSpec used on opensource projects

Example 41 with RegisterSpec

use of com.taobao.android.dx.rop.code.RegisterSpec in project atlas by alibaba.

the class SCCP method replaceConstants.

/**
     * Replaces TypeBearers in source register specs with constant type
     * bearers if possible. These are then referenced in later optimization
     * steps.
     */
private void replaceConstants() {
    for (int reg = 0; reg < regCount; reg++) {
        if (latticeValues[reg] != CONSTANT) {
            continue;
        }
        if (!(latticeConstants[reg] instanceof TypedConstant)) {
            // We can't do much with these
            continue;
        }
        SsaInsn defn = ssaMeth.getDefinitionForRegister(reg);
        TypeBearer typeBearer = defn.getResult().getTypeBearer();
        if (typeBearer.isConstant()) {
            /*
                 * The definition was a constant already.
                 * The uses should be as well.
                 */
            continue;
        }
        // Update the destination RegisterSpec with the constant value
        RegisterSpec dest = defn.getResult();
        RegisterSpec newDest = dest.withType((TypedConstant) latticeConstants[reg]);
        defn.setResult(newDest);
        /*
             * Update the sources RegisterSpec's of all non-move uses.
             * These will be used in later steps.
             */
        for (SsaInsn insn : ssaMeth.getUseListForRegister(reg)) {
            if (insn.isPhiOrMove()) {
                continue;
            }
            NormalSsaInsn nInsn = (NormalSsaInsn) insn;
            RegisterSpecList sources = insn.getSources();
            int index = sources.indexOfRegister(reg);
            RegisterSpec spec = sources.get(index);
            RegisterSpec newSpec = spec.withType((TypedConstant) latticeConstants[reg]);
            nInsn.changeOneSource(index, newSpec);
        }
    }
}

Example 42 with RegisterSpec

use of com.taobao.android.dx.rop.code.RegisterSpec in project atlas by alibaba.

the class SsaBasicBlock method scheduleMovesFromPhis.

/**
     * Sorts move instructions added via {@code addMoveToEnd} during
     * phi removal so that results don't overwrite sources that are used.
     * For use after all phis have been removed and all calls to
     * addMoveToEnd() have been made.<p>
     *
     * This is necessary because copy-propogation may have left us in a state
     * where the same basic block has the same register as a phi operand
     * and a result. In this case, the register in the phi operand always
     * refers value before any other phis have executed.
     */
public void scheduleMovesFromPhis() {
    if (movesFromPhisAtBeginning > 1) {
        List<SsaInsn> toSchedule;
        toSchedule = insns.subList(0, movesFromPhisAtBeginning);
        scheduleUseBeforeAssigned(toSchedule);
        SsaInsn firstNonPhiMoveInsn = insns.get(movesFromPhisAtBeginning);
        /*
             * TODO: It's actually possible that this case never happens,
             * because a move-exception block, having only one predecessor
             * in SSA form, perhaps is never on a dominance frontier.
             */
        if (firstNonPhiMoveInsn.isMoveException()) {
            if (true) {
                /*
                     * We've yet to observe this case, and if it can
                     * occur the code written to handle it probably
                     * does not work.
                     */
                throw new RuntimeException("Unexpected: moves from " + "phis before move-exception");
            } else {
                /*
                     * A move-exception insn must be placed first in this block
                     * We need to move it there, and deal with possible
                     * interference.
                     */
                boolean moveExceptionInterferes = false;
                int moveExceptionResult = firstNonPhiMoveInsn.getResult().getReg();
                /*
                     * Does the move-exception result reg interfere with the
                     * phi moves?
                     */
                for (SsaInsn insn : toSchedule) {
                    if (insn.isResultReg(moveExceptionResult) || insn.isRegASource(moveExceptionResult)) {
                        moveExceptionInterferes = true;
                        break;
                    }
                }
                if (!moveExceptionInterferes) {
                    // This is the easy case.
                    insns.remove(movesFromPhisAtBeginning);
                    insns.add(0, firstNonPhiMoveInsn);
                } else {
                    /*
                         * We need to move the result to a spare reg
                         * and move it back.
                         */
                    RegisterSpec originalResultSpec = firstNonPhiMoveInsn.getResult();
                    int spareRegister = parent.borrowSpareRegister(originalResultSpec.getCategory());
                    // We now move it to a spare register.
                    firstNonPhiMoveInsn.changeResultReg(spareRegister);
                    RegisterSpec tempSpec = firstNonPhiMoveInsn.getResult();
                    insns.add(0, firstNonPhiMoveInsn);
                    // And here we move it back.
                    NormalSsaInsn toAdd = new NormalSsaInsn(new PlainInsn(Rops.opMove(tempSpec.getType()), SourcePosition.NO_INFO, originalResultSpec, RegisterSpecList.make(tempSpec)), this);
                    /*
                         * Place it immediately after the phi-moves,
                         * overwriting the move-exception that was there.
                         */
                    insns.set(movesFromPhisAtBeginning + 1, toAdd);
                }
            }
        }
    }
    if (movesFromPhisAtEnd > 1) {
        scheduleUseBeforeAssigned(insns.subList(insns.size() - movesFromPhisAtEnd - 1, insns.size() - 1));
    }
    // Return registers borrowed here and in scheduleUseBeforeAssigned().
    parent.returnSpareRegisters();
}

Example 43 with RegisterSpec

use of com.taobao.android.dx.rop.code.RegisterSpec in project atlas by alibaba.

the class SsaConverter method placePhiFunctions.

/**
     * See Appel algorithm 19.6:
     *
     * Place Phi functions in appropriate locations.
     *
     * @param ssaMeth {@code non-null;} method to process.
     * Modifications are made in-place.
     * @param localInfo {@code non-null;} local variable info, used
     * when placing phis
     * @param threshold registers below this number are ignored
     */
private static void placePhiFunctions(SsaMethod ssaMeth, LocalVariableInfo localInfo, int threshold) {
    ArrayList<SsaBasicBlock> ssaBlocks;
    int regCount;
    int blockCount;
    ssaBlocks = ssaMeth.getBlocks();
    blockCount = ssaBlocks.size();
    regCount = ssaMeth.getRegCount() - threshold;
    DomFront df = new DomFront(ssaMeth);
    DomFront.DomInfo[] domInfos = df.run();
    // Bit set of registers vs block index "definition sites"
    BitSet[] defsites = new BitSet[regCount];
    // Bit set of registers vs block index "phi placement sites"
    BitSet[] phisites = new BitSet[regCount];
    for (int i = 0; i < regCount; i++) {
        defsites[i] = new BitSet(blockCount);
        phisites[i] = new BitSet(blockCount);
    }
    /*
         * For each register, build a set of all basic blocks where
         * containing an assignment to that register.
         */
    for (int bi = 0, s = ssaBlocks.size(); bi < s; bi++) {
        SsaBasicBlock b = ssaBlocks.get(bi);
        for (SsaInsn insn : b.getInsns()) {
            RegisterSpec rs = insn.getResult();
            if (rs != null && rs.getReg() - threshold >= 0) {
                defsites[rs.getReg() - threshold].set(bi);
            }
        }
    }
    if (DEBUG) {
        System.out.println("defsites");
        for (int i = 0; i < regCount; i++) {
            StringBuilder sb = new StringBuilder();
            sb.append('v').append(i).append(": ");
            sb.append(defsites[i].toString());
            System.out.println(sb);
        }
    }
    BitSet worklist;
    /*
         * For each register, compute all locations for phi placement
         * based on dominance-frontier algorithm.
         */
    for (int reg = 0, s = regCount; reg < s; reg++) {
        int workBlockIndex;
        /* Worklist set starts out with each node where reg is assigned. */
        worklist = (BitSet) (defsites[reg].clone());
        while (0 <= (workBlockIndex = worklist.nextSetBit(0))) {
            worklist.clear(workBlockIndex);
            IntIterator dfIterator = domInfos[workBlockIndex].dominanceFrontiers.iterator();
            while (dfIterator.hasNext()) {
                int dfBlockIndex = dfIterator.next();
                if (!phisites[reg].get(dfBlockIndex)) {
                    phisites[reg].set(dfBlockIndex);
                    int tReg = reg + threshold;
                    RegisterSpec rs = localInfo.getStarts(dfBlockIndex).get(tReg);
                    if (rs == null) {
                        ssaBlocks.get(dfBlockIndex).addPhiInsnForReg(tReg);
                    } else {
                        ssaBlocks.get(dfBlockIndex).addPhiInsnForReg(rs);
                    }
                    if (!defsites[reg].get(dfBlockIndex)) {
                        worklist.set(dfBlockIndex);
                    }
                }
            }
        }
    }
    if (DEBUG) {
        System.out.println("phisites");
        for (int i = 0; i < regCount; i++) {
            StringBuilder sb = new StringBuilder();
            sb.append('v').append(i).append(": ");
            sb.append(phisites[i].toString());
            System.out.println(sb);
        }
    }
}

Example 44 with RegisterSpec

use of com.taobao.android.dx.rop.code.RegisterSpec in project atlas by alibaba.

the class SsaInsn method mapRegisters.

/**
     * Map registers after register allocation.
     *
     * @param mapper {@code non-null;} mapping from old to new registers
     */
public final void mapRegisters(RegisterMapper mapper) {
    RegisterSpec oldResult = result;
    result = mapper.map(result);
    block.getParent().updateOneDefinition(this, oldResult);
    mapSourceRegisters(mapper);
}

Example 45 with RegisterSpec

use of com.taobao.android.dx.rop.code.RegisterSpec in project atlas by alibaba.

the class LivenessAnalyzer method liveOutAtStatement.

/**
     * "v is live-out at s."
     */
private void liveOutAtStatement() {
    SsaInsn statement = blockN.getInsns().get(statementIndex);
    RegisterSpec rs = statement.getResult();
    if (!statement.isResultReg(regV)) {
        if (rs != null) {
            interference.add(regV, rs.getReg());
        }
        nextFunction = NextFunction.LIVE_IN_AT_STATEMENT;
    }
}