1 /* 2 * Copyright (C) 2007 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.android.dx.ssa; 18 19 import com.android.dx.rop.code.*; 20 21 /** 22 * A "normal" (non-phi) instruction in SSA form. Always wraps a rop insn. 23 */ 24 public final class NormalSsaInsn extends SsaInsn implements Cloneable { 25 /** {@code non-null;} rop insn that we're wrapping */ 26 private Insn insn; 27 28 /** 29 * Creates an instance. 30 * 31 * @param insn Rop insn to wrap 32 * @param block block that contains this insn 33 */ 34 NormalSsaInsn(final Insn insn, final SsaBasicBlock block) { 35 super(insn.getResult(), block); 36 this.insn = insn; 37 } 38 39 /** {@inheritDoc} */ 40 @Override 41 public final void mapSourceRegisters(RegisterMapper mapper) { 42 RegisterSpecList oldSources = insn.getSources(); 43 RegisterSpecList newSources = mapper.map(oldSources); 44 45 if (newSources != oldSources) { 46 insn = insn.withNewRegisters(getResult(), newSources); 47 getBlock().getParent().onSourcesChanged(this, oldSources); 48 } 49 } 50 51 /** 52 * Changes one of the insn's sources. New source should be of same type 53 * and category. 54 * 55 * @param index {@code >=0;} index of source to change 56 * @param newSpec spec for new source 57 */ 58 public final void changeOneSource(int index, RegisterSpec newSpec) { 59 RegisterSpecList origSources = insn.getSources(); 60 int sz = origSources.size(); 61 RegisterSpecList newSources = new RegisterSpecList(sz); 62 63 for (int i = 0; i < sz; i++) { 64 newSources.set(i, i == index ? newSpec : origSources.get(i)); 65 } 66 67 newSources.setImmutable(); 68 69 RegisterSpec origSpec = origSources.get(index); 70 if (origSpec.getReg() != newSpec.getReg()) { 71 /* 72 * If the register remains unchanged, we're only changing 73 * the type or local var name so don't update use list 74 */ 75 getBlock().getParent().onSourceChanged(this, origSpec, newSpec); 76 } 77 78 insn = insn.withNewRegisters(getResult(), newSources); 79 } 80 81 /** 82 * Changes the source list of the insn. New source list should be the 83 * same size and consist of sources of identical types. 84 * 85 * @param newSources non-null new sources list. 86 */ 87 public final void setNewSources (RegisterSpecList newSources) { 88 RegisterSpecList origSources = insn.getSources(); 89 90 if (origSources.size() != newSources.size()) { 91 throw new RuntimeException("Sources counts don't match"); 92 } 93 94 insn = insn.withNewRegisters(getResult(), newSources); 95 } 96 97 /** {@inheritDoc} */ 98 @Override 99 public NormalSsaInsn clone() { 100 return (NormalSsaInsn) super.clone(); 101 } 102 103 /** 104 * Like rop.Insn.getSources(). 105 * 106 * @return {@code null-ok;} sources list 107 */ 108 @Override 109 public RegisterSpecList getSources() { 110 return insn.getSources(); 111 } 112 113 /** {@inheritDoc} */ 114 public String toHuman() { 115 return toRopInsn().toHuman(); 116 } 117 118 /** {@inheritDoc} */ 119 @Override 120 public Insn toRopInsn() { 121 return insn.withNewRegisters(getResult(), insn.getSources()); 122 } 123 124 /** 125 * @return the Rop opcode for this insn 126 */ 127 @Override 128 public Rop getOpcode() { 129 return insn.getOpcode(); 130 } 131 132 /** {@inheritDoc} */ 133 @Override 134 public Insn getOriginalRopInsn() { 135 return insn; 136 } 137 138 /** {@inheritDoc} */ 139 @Override 140 public RegisterSpec getLocalAssignment() { 141 RegisterSpec assignment; 142 143 if (insn.getOpcode().getOpcode() == RegOps.MARK_LOCAL) { 144 assignment = insn.getSources().get(0); 145 } else { 146 assignment = getResult(); 147 } 148 149 if (assignment == null) { 150 return null; 151 } 152 153 LocalItem local = assignment.getLocalItem(); 154 155 if (local == null) { 156 return null; 157 } 158 159 return assignment; 160 } 161 162 /** 163 * Upgrades this insn to a version that represents the constant source 164 * literally. If the upgrade is not possible, this does nothing. 165 * 166 * @see Insn#withSourceLiteral 167 */ 168 public void upgradeToLiteral() { 169 RegisterSpecList oldSources = insn.getSources(); 170 171 insn = insn.withSourceLiteral(); 172 getBlock().getParent().onSourcesChanged(this, oldSources); 173 } 174 175 /** 176 * @return true if this is a move (but not a move-operand) instruction 177 */ 178 @Override 179 public boolean isNormalMoveInsn() { 180 return insn.getOpcode().getOpcode() == RegOps.MOVE; 181 } 182 183 /** {@inheritDoc} */ 184 @Override 185 public boolean isMoveException() { 186 return insn.getOpcode().getOpcode() == RegOps.MOVE_EXCEPTION; 187 } 188 189 /** {@inheritDoc} */ 190 @Override 191 public boolean canThrow() { 192 return insn.canThrow(); 193 } 194 195 /** {@inheritDoc} */ 196 @Override 197 public void accept(Visitor v) { 198 if (isNormalMoveInsn()) { 199 v.visitMoveInsn(this); 200 } else { 201 v.visitNonMoveInsn(this); 202 } 203 } 204 205 /** {@inheritDoc} */ 206 @Override 207 public boolean isPhiOrMove() { 208 return isNormalMoveInsn(); 209 } 210 211 /** 212 * {@inheritDoc} 213 * 214 * TODO: Increase the scope of this. 215 */ 216 @Override 217 public boolean hasSideEffect() { 218 Rop opcode = getOpcode(); 219 220 if (opcode.getBranchingness() != Rop.BRANCH_NONE) { 221 return true; 222 } 223 224 boolean hasLocalSideEffect 225 = Optimizer.getPreserveLocals() && getLocalAssignment() != null; 226 227 switch (opcode.getOpcode()) { 228 case RegOps.MOVE_RESULT: 229 case RegOps.MOVE: 230 case RegOps.CONST: 231 return hasLocalSideEffect; 232 default: 233 return true; 234 } 235 } 236 } 237
