| /* |
| * Copyright (C) 2007 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.android.dx.rop.code; |
| |
| import com.android.dx.rop.cst.Constant; |
| import com.android.dx.rop.cst.CstInteger; |
| import com.android.dx.rop.type.StdTypeList; |
| import com.android.dx.rop.type.Type; |
| import com.android.dx.rop.type.TypeBearer; |
| import com.android.dx.rop.type.TypeList; |
| |
| /** |
| * Plain instruction, which has no embedded data and which cannot possibly |
| * throw an exception. |
| */ |
| public final class PlainInsn |
| extends Insn { |
| /** |
| * Constructs an instance. |
| * |
| * @param opcode {@code non-null;} the opcode |
| * @param position {@code non-null;} source position |
| * @param result {@code null-ok;} spec for the result, if any |
| * @param sources {@code non-null;} specs for all the sources |
| */ |
| public PlainInsn(Rop opcode, SourcePosition position, |
| RegisterSpec result, RegisterSpecList sources) { |
| super(opcode, position, result, sources); |
| |
| switch (opcode.getBranchingness()) { |
| case Rop.BRANCH_SWITCH: |
| case Rop.BRANCH_THROW: { |
| throw new IllegalArgumentException("bogus branchingness"); |
| } |
| } |
| |
| if (result != null && opcode.getBranchingness() != Rop.BRANCH_NONE) { |
| // move-result-pseudo is required here |
| throw new IllegalArgumentException |
| ("can't mix branchingness with result"); |
| } |
| } |
| |
| /** |
| * Constructs a single-source instance. |
| * |
| * @param opcode {@code non-null;} the opcode |
| * @param position {@code non-null;} source position |
| * @param result {@code null-ok;} spec for the result, if any |
| * @param source {@code non-null;} spec for the source |
| */ |
| public PlainInsn(Rop opcode, SourcePosition position, RegisterSpec result, |
| RegisterSpec source) { |
| this(opcode, position, result, RegisterSpecList.make(source)); |
| } |
| |
| /** {@inheritDoc} */ |
| @Override |
| public TypeList getCatches() { |
| return StdTypeList.EMPTY; |
| } |
| |
| /** {@inheritDoc} */ |
| @Override |
| public void accept(Visitor visitor) { |
| visitor.visitPlainInsn(this); |
| } |
| |
| /** {@inheritDoc} */ |
| @Override |
| public Insn withAddedCatch(Type type) { |
| throw new UnsupportedOperationException("unsupported"); |
| } |
| |
| /** {@inheritDoc} */ |
| @Override |
| public Insn withRegisterOffset(int delta) { |
| return new PlainInsn(getOpcode(), getPosition(), |
| getResult().withOffset(delta), |
| getSources().withOffset(delta)); |
| } |
| |
| /** {@inheritDoc} */ |
| @Override |
| public Insn withSourceLiteral() { |
| RegisterSpecList sources = getSources(); |
| int szSources = sources.size(); |
| |
| if (szSources == 0) { |
| return this; |
| } |
| |
| TypeBearer lastType = sources.get(szSources - 1).getTypeBearer(); |
| |
| if (!lastType.isConstant()) { |
| // Check for reverse subtraction, where first source is constant |
| TypeBearer firstType = sources.get(0).getTypeBearer(); |
| if (szSources == 2 && firstType.isConstant()) { |
| Constant cst = (Constant) firstType; |
| RegisterSpecList newSources = sources.withoutFirst(); |
| Rop newRop = Rops.ropFor(getOpcode().getOpcode(), getResult(), |
| newSources, cst); |
| return new PlainCstInsn(newRop, getPosition(), getResult(), |
| newSources, cst); |
| } |
| return this; |
| } else { |
| |
| Constant cst = (Constant) lastType; |
| |
| RegisterSpecList newSources = sources.withoutLast(); |
| |
| Rop newRop; |
| try { |
| // Check for constant subtraction and flip it to be addition |
| int opcode = getOpcode().getOpcode(); |
| if (opcode == RegOps.SUB && cst instanceof CstInteger) { |
| opcode = RegOps.ADD; |
| cst = CstInteger.make(-((CstInteger)cst).getValue()); |
| } |
| newRop = Rops.ropFor(opcode, getResult(), newSources, cst); |
| } catch (IllegalArgumentException ex) { |
| // There's no rop for this case |
| return this; |
| } |
| |
| return new PlainCstInsn(newRop, getPosition(), |
| getResult(), newSources, cst); |
| } |
| } |
| |
| |
| /** {@inheritDoc} */ |
| @Override |
| public Insn withNewRegisters(RegisterSpec result, |
| RegisterSpecList sources) { |
| |
| return new PlainInsn(getOpcode(), getPosition(), |
| result, |
| sources); |
| |
| } |
| } |