Examples with LocationOperand org.jikesrvm.compilers.opt.ir.operand.LocationOperand used on opensource projects

Example 6 with LocationOperand

use of org.jikesrvm.compilers.opt.ir.operand.LocationOperand in project JikesRVM by JikesRVM.

the class ComplexLIR2MIRExpansion method attempt.

private static void attempt(Instruction s, IR ir, boolean isAddress, boolean isLong) {
    BasicBlock BB1 = s.getBasicBlock();
    BasicBlock BB4 = BB1.splitNodeAt(s, ir);
    BasicBlock BB2 = BB1.createSubBlock(0, ir);
    BasicBlock BB3 = BB2.createSubBlock(0, ir);
    BB1.insertOut(BB2);
    BB1.insertOut(BB3);
    BB2.insertOut(BB4);
    BB3.insertOut(BB4);
    ir.cfg.linkInCodeOrder(BB1, BB2);
    ir.cfg.linkInCodeOrder(BB2, BB3);
    ir.cfg.linkInCodeOrder(BB3, BB4);
    // mutate ATTEMPT into a STWCX
    RegisterOperand newValue = (RegisterOperand) Attempt.getNewValue(s);
    RegisterOperand address = (RegisterOperand) Attempt.getAddress(s);
    Operand offset = Attempt.getOffset(s);
    LocationOperand location = Attempt.getLocation(s);
    Operand guard = Attempt.getGuard(s);
    RegisterOperand result = Attempt.getResult(s);
    MIR_Store.mutate(s, (isAddress || isLong ? PPC_STAddrCXr : PPC_STWCXr), newValue, address, offset, location, guard);
    // Branch to BB3 iff the STWXC succeeds (CR(0) is EQUAL)
    // Else fall through to BB2
    PhysicalRegisterSet phys = ir.regpool.getPhysicalRegisterSet().asPPC();
    BB1.appendInstruction(MIR_CondBranch.create(PPC_BCOND, I(phys.getConditionRegister(0)), PowerPCConditionOperand.EQUAL(), BB3.makeJumpTarget(), new BranchProfileOperand()));
    // BB2 sets result to FALSE and jumps to BB4
    BB2.appendInstruction(MIR_Unary.create(PPC_LDI, result.copyRO(), IC(0)));
    BB2.appendInstruction(MIR_Branch.create(PPC_B, BB4.makeJumpTarget()));
    // BB3 sets result to TRUE and falls through to BB4
    BB3.appendInstruction(MIR_Unary.create(PPC_LDI, result.copyRO(), IC(1)));
}

Example 7 with LocationOperand

use of org.jikesrvm.compilers.opt.ir.operand.LocationOperand in project JikesRVM by JikesRVM.

the class NormalizeConstants method perform.

/**
 * Doit.
 *
 * @param ir IR to normalize
 */
public static void perform(IR ir) {
    // This greatly reduces the number of cases we have to worry about below.
    if (VM.VerifyAssertions)
        VM._assert(ir.options.SIMPLIFY_INTEGER_OPS && ir.options.SIMPLIFY_LONG_OPS && ir.options.SIMPLIFY_REF_OPS);
    for (Instruction s = ir.firstInstructionInCodeOrder(); s != null; s = s.nextInstructionInCodeOrder()) {
        // STEP ONE: Get 'large' constants into a form that the PPC BURS rules
        // are prepared to deal with.
        // Constants can't appear as defs, so only scan the uses.
        // 
        int numUses = s.getNumberOfUses();
        if (numUses > 0) {
            int numDefs = s.getNumberOfDefs();
            for (int idx = numDefs; idx < numUses + numDefs; idx++) {
                Operand use = s.getOperand(idx);
                if (use != null) {
                    if (use instanceof ObjectConstantOperand) {
                        RegisterOperand rop = ir.regpool.makeTemp(use.getType());
                        RegisterOperand jtoc = (RegisterOperand) ir.regpool.makeJTOCOp();
                        ObjectConstantOperand oc = (ObjectConstantOperand) use;
                        Offset offset = oc.offset;
                        if (offset.isZero()) {
                            if (use instanceof StringConstantOperand) {
                                throw new OptimizingCompilerException("String constant w/o valid JTOC offset");
                            } else if (use instanceof ClassConstantOperand) {
                                throw new OptimizingCompilerException("Class constant w/o valid JTOC offset");
                            }
                            offset = Offset.fromIntSignExtend(Statics.findOrCreateObjectLiteral(oc.value));
                        }
                        LocationOperand loc = new LocationOperand(offset);
                        s.insertBefore(Load.create(VM.BuildFor32Addr ? INT_LOAD : LONG_LOAD, rop, jtoc, asImmediateOrRegOffset(AC(offset), s, ir, true), loc));
                        s.putOperand(idx, rop.copyD2U());
                    } else if (use instanceof DoubleConstantOperand) {
                        RegisterOperand rop = ir.regpool.makeTemp(TypeReference.Double);
                        RegisterOperand jtoc = (RegisterOperand) ir.regpool.makeJTOCOp();
                        DoubleConstantOperand dc = (DoubleConstantOperand) use;
                        Offset offset = dc.offset;
                        if (offset.isZero()) {
                            offset = Offset.fromIntSignExtend(Statics.findOrCreateLongSizeLiteral(Double.doubleToLongBits(dc.value)));
                        }
                        LocationOperand loc = new LocationOperand(offset);
                        s.insertBefore(Load.create(DOUBLE_LOAD, rop, jtoc, asImmediateOrRegOffset(AC(offset), s, ir, true), loc));
                        s.putOperand(idx, rop.copyD2U());
                    } else if (use instanceof FloatConstantOperand) {
                        RegisterOperand rop = ir.regpool.makeTemp(TypeReference.Float);
                        RegisterOperand jtoc = (RegisterOperand) ir.regpool.makeJTOCOp();
                        FloatConstantOperand fc = (FloatConstantOperand) use;
                        Offset offset = fc.offset;
                        if (offset.isZero()) {
                            offset = Offset.fromIntSignExtend(Statics.findOrCreateIntSizeLiteral(Float.floatToIntBits(fc.value)));
                        }
                        LocationOperand loc = new LocationOperand(offset);
                        s.insertBefore(Load.create(FLOAT_LOAD, rop, jtoc, asImmediateOrRegOffset(AC(offset), s, ir, true), loc));
                        s.putOperand(idx, rop.copyD2U());
                    } else if (use instanceof LongConstantOperand) {
                        if (!VM.BuildFor64Addr) {
                            if (s.getOpcode() != TRAP_IF_opcode) {
                                RegisterOperand rop = ir.regpool.makeTemp(TypeReference.Long);
                                s.insertBefore(Move.create(LONG_MOVE, rop, use.copy()));
                                s.putOperand(idx, rop.copyD2U());
                            }
                        }
                    } else if (use instanceof NullConstantOperand) {
                        s.putOperand(idx, AC(Address.zero()));
                    } else if (use instanceof TIBConstantOperand) {
                        RegisterOperand rop = ir.regpool.makeTemp(TypeReference.JavaLangObjectArray);
                        Operand jtoc = ir.regpool.makeJTOCOp();
                        Offset offset = ((TIBConstantOperand) use).value.getTibOffset();
                        LocationOperand loc = new LocationOperand(offset);
                        s.insertBefore(Load.create(VM.BuildFor32Addr ? INT_LOAD : LONG_LOAD, rop, jtoc, asImmediateOrRegOffset(AC(offset), s, ir, true), loc));
                        s.putOperand(idx, rop.copyD2U());
                    } else if (use instanceof CodeConstantOperand) {
                        RegisterOperand rop = ir.regpool.makeTemp(TypeReference.CodeArray);
                        Operand jtoc = ir.regpool.makeJTOCOp();
                        Offset offset = ((CodeConstantOperand) use).value.findOrCreateJtocOffset();
                        LocationOperand loc = new LocationOperand(offset);
                        s.insertBefore(Load.create(VM.BuildFor32Addr ? INT_LOAD : LONG_LOAD, rop, jtoc, asImmediateOrRegOffset(AC(offset), s, ir, true), loc));
                        s.putOperand(idx, rop.copyD2U());
                    }
                }
            }
        }
        // Calling Simplifier.simplify ensures that the instruction is
        // in normalized form. This reduces the number of cases we have to
        // worry about (and does last minute constant folding on the off chance
        // we've missed an opportunity...)
        Simplifier.simplify(false, ir.regpool, ir.options, s);
        switch(s.getOpcode()) {
            // ////////
            case REF_STORE_opcode:
                s.changeOperatorTo(VM.BuildFor32Addr ? INT_STORE : LONG_STORE);
                // On PowerPC, the value being stored must be in a register
                Store.setValue(s, asRegPolymorphic(Store.getClearValue(s), s, ir));
                // Supported addressing modes are quite limited.
                Store.setAddress(s, asRegAddress(Store.getClearAddress(s), s, ir));
                Store.setOffset(s, asImmediateOrRegOffset(Store.getClearOffset(s), s, ir, true));
                break;
            case BYTE_STORE_opcode:
            case SHORT_STORE_opcode:
            case INT_STORE_opcode:
            case LONG_STORE_opcode:
                // On PowerPC, the value being stored must be in a register
                Store.setValue(s, asRegPolymorphic(Store.getClearValue(s), s, ir));
                // Supported addressing modes are quite limited.
                Store.setAddress(s, asRegAddress(Store.getClearAddress(s), s, ir));
                Store.setOffset(s, asImmediateOrRegOffset(Store.getClearOffset(s), s, ir, true));
                break;
            case FLOAT_STORE_opcode:
            case DOUBLE_STORE_opcode:
                // Supported addressing modes are quite limited.
                Store.setAddress(s, asRegAddress(Store.getClearAddress(s), s, ir));
                Store.setOffset(s, asImmediateOrRegOffset(Store.getClearOffset(s), s, ir, true));
                break;
            case REF_LOAD_opcode:
                s.changeOperatorTo(VM.BuildFor32Addr ? INT_LOAD : LONG_LOAD);
                // Supported addressing modes are quite limited.
                Load.setAddress(s, asRegAddress(Load.getClearAddress(s), s, ir));
                Load.setOffset(s, asImmediateOrRegOffset(Load.getClearOffset(s), s, ir, true));
                break;
            case BYTE_LOAD_opcode:
            case UBYTE_LOAD_opcode:
            case SHORT_LOAD_opcode:
            case USHORT_LOAD_opcode:
            case INT_LOAD_opcode:
            case LONG_LOAD_opcode:
            case FLOAT_LOAD_opcode:
            case DOUBLE_LOAD_opcode:
                // Supported addressing modes are quite limited.
                Load.setAddress(s, asRegAddress(Load.getClearAddress(s), s, ir));
                Load.setOffset(s, asImmediateOrRegOffset(Load.getClearOffset(s), s, ir, true));
                break;
            case ATTEMPT_INT_opcode:
            case ATTEMPT_LONG_opcode:
            case ATTEMPT_ADDR_opcode:
                // On PowerPC, the value being stored must be in a register
                Attempt.setNewValue(s, asRegPolymorphic(Attempt.getClearNewValue(s), s, ir));
                // not used on powerpc.
                Attempt.setOldValue(s, null);
                // Supported addressing modes are quite limited.
                Attempt.setAddress(s, asRegAddress(Attempt.getClearAddress(s), s, ir));
                Attempt.setOffset(s, asRegOffset(Attempt.getClearOffset(s), s, ir));
                break;
            case PREPARE_INT_opcode:
            case PREPARE_LONG_opcode:
            case PREPARE_ADDR_opcode:
                // Supported addressing modes are quite limited.
                Prepare.setAddress(s, asRegAddress(Prepare.getClearAddress(s), s, ir));
                Prepare.setOffset(s, asRegOffset(Prepare.getClearOffset(s), s, ir));
                break;
            case LONG_MOVE_opcode:
                if (VM.BuildFor64Addr) {
                    s.changeOperatorTo(REF_MOVE);
                }
                break;
            case INT_MOVE_opcode:
                s.changeOperatorTo(REF_MOVE);
                break;
            case REF_COND_MOVE_opcode:
                s.changeOperatorTo(VM.BuildFor32Addr ? INT_COND_MOVE : LONG_COND_MOVE);
                break;
            case REF_IFCMP_opcode:
                s.changeOperatorTo(VM.BuildFor32Addr ? INT_IFCMP : LONG_IFCMP);
                // val1 can't be a constant, val2 must be small enough.
                IfCmp.setVal1(s, asRegPolymorphic(IfCmp.getClearVal1(s), s, ir));
                IfCmp.setVal2(s, asImmediateOrRegPolymorphic(IfCmp.getClearVal2(s), s, ir, true));
            case LONG_IFCMP_opcode:
                if (VM.BuildFor64Addr) {
                    // val1 can't be a constant, val2 must be small enough.
                    IfCmp.setVal1(s, asRegPolymorphic(IfCmp.getClearVal1(s), s, ir));
                    IfCmp.setVal2(s, asImmediateOrRegPolymorphic(IfCmp.getClearVal2(s), s, ir, true));
                }
                break;
            case INT_IFCMP_opcode:
                // val1 can't be a constant, val2 must be small enough.
                IfCmp.setVal1(s, asRegPolymorphic(IfCmp.getClearVal1(s), s, ir));
                IfCmp.setVal2(s, asImmediateOrRegPolymorphic(IfCmp.getClearVal2(s), s, ir, true));
                break;
            case INT_IFCMP2_opcode:
                // val1 can't be a constant, val2 must be small enough.
                IfCmp2.setVal1(s, asRegInt(IfCmp2.getClearVal1(s), s, ir));
                IfCmp2.setVal2(s, asImmediateOrRegInt(IfCmp2.getClearVal2(s), s, ir, true));
                break;
            case BOOLEAN_CMP_INT_opcode:
            case BOOLEAN_CMP_ADDR_opcode:
                // val2 must be small enough.
                BooleanCmp.setVal2(s, asImmediateOrRegPolymorphic(BooleanCmp.getClearVal2(s), s, ir, !BooleanCmp.getCond(s).isUNSIGNED()));
                break;
            case LONG_CMP_opcode:
                Binary.setVal1(s, asRegPolymorphic(Binary.getVal1(s), s, ir));
                Binary.setVal2(s, asRegPolymorphic(Binary.getVal2(s), s, ir));
                break;
            case LONG_ADD_opcode:
                if (VM.BuildFor64Addr) {
                    s.changeOperatorTo(REF_ADD);
                    Binary.setVal2(s, asImmediateOrRegPolymorphic(Binary.getClearVal2(s), s, ir, true));
                }
                break;
            case INT_ADD_opcode:
                s.changeOperatorTo(REF_ADD);
                Binary.setVal2(s, asImmediateOrRegPolymorphic(Binary.getClearVal2(s), s, ir, true));
                break;
            case REF_ADD_opcode:
                Binary.setVal2(s, asImmediateOrRegPolymorphic(Binary.getClearVal2(s), s, ir, true));
                break;
            case LONG_SUB_opcode:
                if (VM.BuildFor64Addr) {
                    s.changeOperatorTo(REF_SUB);
                    Binary.setVal1(s, asImmediateOrRegPolymorphic(Binary.getClearVal1(s), s, ir, true));
                // val2 isn't be constant (if it were, Simplifier would have
                // converted this into an ADD of -Val2).
                }
                break;
            case INT_SUB_opcode:
                s.changeOperatorTo(REF_SUB);
                Binary.setVal1(s, asImmediateOrRegPolymorphic(Binary.getClearVal1(s), s, ir, true));
                // converted this into an ADD of -Val2).
                break;
            case REF_SUB_opcode:
                Binary.setVal1(s, asImmediateOrRegPolymorphic(Binary.getClearVal1(s), s, ir, true));
                // converted this into an ADD of -Val2).
                break;
            case INT_MUL_opcode:
                Binary.setVal2(s, asImmediateOrRegInt(Binary.getClearVal2(s), s, ir, true));
                break;
            case LONG_MUL_opcode:
                if (VM.BuildFor64Addr) {
                    Binary.setVal2(s, asImmediateOrRegLong(Binary.getClearVal2(s), s, ir, true));
                }
                break;
            // seem to expect constant operands at all.
            case INT_REM_opcode:
            case INT_DIV_opcode:
                GuardedBinary.setVal1(s, asRegInt(GuardedBinary.getClearVal1(s), s, ir));
                GuardedBinary.setVal2(s, asRegInt(GuardedBinary.getClearVal2(s), s, ir));
                break;
            case LONG_REM_opcode:
            case LONG_DIV_opcode:
                if (VM.BuildFor64Addr) {
                    GuardedBinary.setVal1(s, asRegLong(GuardedBinary.getClearVal1(s), s, ir));
                    GuardedBinary.setVal2(s, asRegLong(GuardedBinary.getClearVal2(s), s, ir));
                }
                break;
            case LONG_NEG_opcode:
                if (VM.BuildFor64Addr) {
                    s.changeOperatorTo(REF_NEG);
                }
                break;
            case INT_NEG_opcode:
                s.changeOperatorTo(REF_NEG);
                break;
            case LONG_NOT_opcode:
                if (VM.BuildFor64Addr) {
                    s.changeOperatorTo(REF_NOT);
                }
                break;
            case INT_NOT_opcode:
                s.changeOperatorTo(REF_NOT);
                break;
            case LONG_AND_opcode:
                if (VM.BuildFor64Addr) {
                    s.changeOperatorTo(REF_AND);
                    // unsigned immediate
                    Binary.setVal2(s, asImmediateOrRegPolymorphic(Binary.getClearVal2(s), s, ir, false));
                }
                break;
            case INT_AND_opcode:
                s.changeOperatorTo(REF_AND);
                // unsigned immediate
                Binary.setVal2(s, asImmediateOrRegPolymorphic(Binary.getClearVal2(s), s, ir, false));
                break;
            case REF_AND_opcode:
                // unsigned immediate
                Binary.setVal2(s, asImmediateOrRegPolymorphic(Binary.getClearVal2(s), s, ir, false));
                break;
            case LONG_OR_opcode:
                if (VM.BuildFor64Addr) {
                    s.changeOperatorTo(REF_OR);
                    // unsigned immediate
                    Binary.setVal2(s, asImmediateOrRegPolymorphic(Binary.getClearVal2(s), s, ir, false));
                }
                break;
            case INT_OR_opcode:
                s.changeOperatorTo(REF_OR);
                // unsigned immediate
                Binary.setVal2(s, asImmediateOrRegPolymorphic(Binary.getClearVal2(s), s, ir, false));
                break;
            case REF_OR_opcode:
                // unsigned immediate
                Binary.setVal2(s, asImmediateOrRegPolymorphic(Binary.getClearVal2(s), s, ir, false));
                break;
            case LONG_XOR_opcode:
                if (VM.BuildFor64Addr) {
                    s.changeOperatorTo(REF_XOR);
                    // unsigned immediate
                    Binary.setVal2(s, asImmediateOrRegPolymorphic(Binary.getClearVal2(s), s, ir, false));
                }
                break;
            case INT_XOR_opcode:
                s.changeOperatorTo(REF_XOR);
                // unsigned immediate
                Binary.setVal2(s, asImmediateOrRegPolymorphic(Binary.getClearVal2(s), s, ir, false));
                break;
            case REF_XOR_opcode:
                // unsigned immediate
                Binary.setVal2(s, asImmediateOrRegPolymorphic(Binary.getClearVal2(s), s, ir, false));
                break;
            case REF_SHL_opcode:
                s.changeOperatorTo(VM.BuildFor32Addr ? INT_SHL : LONG_SHL);
                // Val2 could be a constant, but Val1 apparently can't be.
                Binary.setVal1(s, asRegPolymorphic(Binary.getClearVal1(s), s, ir));
                break;
            case LONG_SHL_opcode:
                if (VM.BuildFor64Addr) {
                    // Val2 could be a constant, but Val1 apparently can't be.
                    Binary.setVal1(s, asRegPolymorphic(Binary.getClearVal1(s), s, ir));
                }
                break;
            case INT_SHL_opcode:
                // Val2 could be a constant, but Val1 apparently can't be.
                Binary.setVal1(s, asRegPolymorphic(Binary.getClearVal1(s), s, ir));
                break;
            case REF_SHR_opcode:
                s.changeOperatorTo(VM.BuildFor32Addr ? INT_SHR : LONG_SHR);
                // Val2 could be a constant, but Val1 apparently can't be.
                Binary.setVal1(s, asRegPolymorphic(Binary.getClearVal1(s), s, ir));
                break;
            case LONG_SHR_opcode:
                if (VM.BuildFor64Addr) {
                    // Val2 could be a constant, but Val1 apparently can't be.
                    Binary.setVal1(s, asRegPolymorphic(Binary.getClearVal1(s), s, ir));
                }
                break;
            case INT_SHR_opcode:
                // Val2 could be a constant, but Val1 apparently can't be.
                Binary.setVal1(s, asRegPolymorphic(Binary.getClearVal1(s), s, ir));
                break;
            case REF_USHR_opcode:
                s.changeOperatorTo(VM.BuildFor32Addr ? INT_USHR : LONG_USHR);
                // Val2 could be a constant, but Val1 apparently can't be.
                Binary.setVal1(s, asRegPolymorphic(Binary.getClearVal1(s), s, ir));
                break;
            case LONG_USHR_opcode:
                if (VM.BuildFor64Addr) {
                    // Val2 could be a constant, but Val1 apparently can't be.
                    Binary.setVal1(s, asRegPolymorphic(Binary.getClearVal1(s), s, ir));
                }
                break;
            case INT_USHR_opcode:
                // Val2 could be a constant, but Val1 apparently can't be.
                Binary.setVal1(s, asRegPolymorphic(Binary.getClearVal1(s), s, ir));
                break;
            // Deal with Simplifier.CF_FLOAT or Simplifier.CF_DOUBLE being false
            case INT_2DOUBLE_opcode:
            case INT_2FLOAT_opcode:
            case INT_BITS_AS_FLOAT_opcode:
                Unary.setVal(s, asRegInt(Unary.getVal(s), s, ir));
                break;
            case ADDR_2INT_opcode:
                s.changeOperatorTo(VM.BuildFor32Addr ? REF_MOVE : LONG_2INT);
                break;
            case ADDR_2LONG_opcode:
                s.changeOperatorTo(VM.BuildFor32Addr ? INT_2LONG : REF_MOVE);
                break;
            case INT_2ADDRSigExt_opcode:
                s.changeOperatorTo(VM.BuildFor32Addr ? REF_MOVE : INT_2LONG);
                break;
            case INT_2ADDRZerExt_opcode:
                if (VM.BuildFor32Addr) {
                    s.changeOperatorTo(REF_MOVE);
                }
                break;
            case LONG_2ADDR_opcode:
                s.changeOperatorTo(VM.BuildFor64Addr ? REF_MOVE : LONG_2INT);
                break;
            case NULL_CHECK_opcode:
                NullCheck.setRef(s, asRegAddress(NullCheck.getClearRef(s), s, ir));
                break;
            // Force all call parameters to be in registers
            case SYSCALL_opcode:
            case CALL_opcode:
                {
                    int numArgs = Call.getNumberOfParams(s);
                    for (int i = 0; i < numArgs; i++) {
                        Call.setParam(s, i, asRegPolymorphic(Call.getClearParam(s, i), s, ir));
                    }
                }
                break;
            case RETURN_opcode:
                if (Return.hasVal(s)) {
                    Return.setVal(s, asRegPolymorphic(Return.getClearVal(s), s, ir));
                }
                break;
        }
    }
}

Example 8 with LocationOperand

use of org.jikesrvm.compilers.opt.ir.operand.LocationOperand in project JikesRVM by JikesRVM.

the class SSADictionary method getStaticHelper.

/**
 * Record the effects of a getstatic instruction on the heap array
 * SSA form.  Register the heap variables that this instruction uses and
 * defs.  Note that if inserting uphi functions, a getstatic defs a new
 * heap variable name.
 *
 * @param s the getstatic instruction
 * @param b the basic block containing s
 */
private void getStaticHelper(Instruction s, BasicBlock b) {
    LocationOperand locOp = GetStatic.getLocation(s);
    FieldReference field = locOp.getFieldRef();
    registerUse(s, field);
    if (uphi) {
        registerDef(s, b, field);
    }
}

Example 9 with LocationOperand

use of org.jikesrvm.compilers.opt.ir.operand.LocationOperand in project JikesRVM by JikesRVM.

the class SSADictionary method putStaticHelper.

/**
 * Record the effects of a putstatic instruction on the heap array
 * SSA form.  Register the heap variables that this instruction uses and
 * defs.
 *
 * @param s the putstatic instruction
 * @param b the basic block containing s
 */
private void putStaticHelper(Instruction s, BasicBlock b) {
    LocationOperand locOp = PutStatic.getLocation(s);
    FieldReference field = locOp.getFieldRef();
    registerUse(s, field);
    registerDef(s, b, field);
}

Example 10 with LocationOperand

use of org.jikesrvm.compilers.opt.ir.operand.LocationOperand in project JikesRVM by JikesRVM.

the class LICM method checkLoop.

/*
   * TODO document xidx parameter and turn this comment into proper JavaDoc.
   * <p>
   * Checks that inside the loop, the heap variable is only used/defed
   * by simple, non-volatile loads/stores
   *
   * @param inst a phi instruction
   * @param hop the result operand of the phi instruction
   * @param xidx
   * @param block the block that contains the phi instruction
   *
   * @return one of {@link #CL_LOADS_ONLY}, {@link #CL_STORES_ONLY},
   * {@link #CL_LOADS_AND_STORES}, {@link #CL_COMPLEX}
   */
private int checkLoop(Instruction inst, HeapOperand<Object> hop, int xidx, BasicBlock block) {
    HashSet<Instruction> seen = new HashSet<Instruction>();
    Queue<Instruction> workList = new Queue<Instruction>();
    int _state = CL_NONE;
    int instUses = 0;
    seen.add(inst);
    for (int i = Phi.getNumberOfValues(inst) - 1; i >= 0; --i) {
        if (i == xidx)
            continue;
        Instruction y = definingInstruction(Phi.getValue(inst, i));
        if (y == inst)
            instUses++;
        if (!(seen.contains(y))) {
            seen.add(y);
            workList.insert(y);
        }
    }
    while (!(workList.isEmpty())) {
        Instruction y = workList.remove();
        if (Phi.conforms(y)) {
            for (int i = Phi.getNumberOfValues(y) - 1; i >= 0; --i) {
                Instruction z = definingInstruction(Phi.getValue(y, i));
                if (z == inst)
                    instUses++;
                if (!(seen.contains(z))) {
                    seen.add(z);
                    workList.insert(z);
                }
            }
        } else if ((y.isPEI()) || !LocationCarrier.conforms(y) || y.operator().isAcquire() || y.operator().isRelease()) {
            return CL_COMPLEX;
        } else {
            // check for access to volatile field
            LocationOperand loc = LocationCarrier.getLocation(y);
            if (loc == null || loc.mayBeVolatile()) {
                // VM.sysWriteln (" no loc or volatile field");
                return CL_COMPLEX;
            }
            if (y.isImplicitStore()) {
                // conservatively estimate loop-invariance by header domination
                if (!inVariantLocation(y, block))
                    return CL_COMPLEX;
                _state |= CL_STORES_ONLY;
            } else {
                _state |= CL_LOADS_ONLY;
            }
            for (HeapOperand<?> op : ssad.getHeapUses(y)) {
                if (op.value.isExceptionHeapType())
                    continue;
                if (op.getHeapType() != hop.getHeapType())
                    return CL_COMPLEX;
                y = definingInstruction(op);
                if (y == inst)
                    instUses++;
                if (!(seen.contains(y))) {
                    seen.add(y);
                    workList.insert(y);
                }
            }
        }
    }
    if (_state == CL_STORES_ONLY && ssad.getNumberOfUses(hop.value) != instUses) {
        return CL_COMPLEX;
    }
    return _state;
}