1// Copyright 2014, ARM Limited 2// All rights reserved. 3// 4// Redistribution and use in source and binary forms, with or without 5// modification, are permitted provided that the following conditions are met: 6// 7// * Redistributions of source code must retain the above copyright notice, 8// this list of conditions and the following disclaimer. 9// * Redistributions in binary form must reproduce the above copyright notice, 10// this list of conditions and the following disclaimer in the documentation 11// and/or other materials provided with the distribution. 12// * Neither the name of ARM Limited nor the names of its contributors may be 13// used to endorse or promote products derived from this software without 14// specific prior written permission. 15// 16// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS CONTRIBUTORS "AS IS" AND 17// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 18// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 19// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE 20// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 22// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 23// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24// OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 25// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 27#ifndef VIXL_A64_DECODER_A64_H_ 28#define VIXL_A64_DECODER_A64_H_ 29 30#include <list> 31 32#include "vixl/globals.h" 33#include "vixl/a64/instructions-a64.h" 34 35 36// List macro containing all visitors needed by the decoder class. 37 38#define VISITOR_LIST_THAT_RETURN(V) \ 39 V(PCRelAddressing) \ 40 V(AddSubImmediate) \ 41 V(LogicalImmediate) \ 42 V(MoveWideImmediate) \ 43 V(Bitfield) \ 44 V(Extract) \ 45 V(UnconditionalBranch) \ 46 V(UnconditionalBranchToRegister) \ 47 V(CompareBranch) \ 48 V(TestBranch) \ 49 V(ConditionalBranch) \ 50 V(System) \ 51 V(Exception) \ 52 V(LoadStorePairPostIndex) \ 53 V(LoadStorePairOffset) \ 54 V(LoadStorePairPreIndex) \ 55 V(LoadStorePairNonTemporal) \ 56 V(LoadLiteral) \ 57 V(LoadStoreUnscaledOffset) \ 58 V(LoadStorePostIndex) \ 59 V(LoadStorePreIndex) \ 60 V(LoadStoreRegisterOffset) \ 61 V(LoadStoreUnsignedOffset) \ 62 V(LoadStoreExclusive) \ 63 V(LogicalShifted) \ 64 V(AddSubShifted) \ 65 V(AddSubExtended) \ 66 V(AddSubWithCarry) \ 67 V(ConditionalCompareRegister) \ 68 V(ConditionalCompareImmediate) \ 69 V(ConditionalSelect) \ 70 V(DataProcessing1Source) \ 71 V(DataProcessing2Source) \ 72 V(DataProcessing3Source) \ 73 V(FPCompare) \ 74 V(FPConditionalCompare) \ 75 V(FPConditionalSelect) \ 76 V(FPImmediate) \ 77 V(FPDataProcessing1Source) \ 78 V(FPDataProcessing2Source) \ 79 V(FPDataProcessing3Source) \ 80 V(FPIntegerConvert) \ 81 V(FPFixedPointConvert) \ 82 V(Crypto2RegSHA) \ 83 V(Crypto3RegSHA) \ 84 V(CryptoAES) \ 85 V(NEON2RegMisc) \ 86 V(NEON3Different) \ 87 V(NEON3Same) \ 88 V(NEONAcrossLanes) \ 89 V(NEONByIndexedElement) \ 90 V(NEONCopy) \ 91 V(NEONExtract) \ 92 V(NEONLoadStoreMultiStruct) \ 93 V(NEONLoadStoreMultiStructPostIndex) \ 94 V(NEONLoadStoreSingleStruct) \ 95 V(NEONLoadStoreSingleStructPostIndex) \ 96 V(NEONModifiedImmediate) \ 97 V(NEONScalar2RegMisc) \ 98 V(NEONScalar3Diff) \ 99 V(NEONScalar3Same) \ 100 V(NEONScalarByIndexedElement) \ 101 V(NEONScalarCopy) \ 102 V(NEONScalarPairwise) \ 103 V(NEONScalarShiftImmediate) \ 104 V(NEONShiftImmediate) \ 105 V(NEONTable) \ 106 V(NEONPerm) \ 107 108#define VISITOR_LIST_THAT_DONT_RETURN(V) \ 109 V(Unallocated) \ 110 V(Unimplemented) \ 111 112#define VISITOR_LIST(V) \ 113 VISITOR_LIST_THAT_RETURN(V) \ 114 VISITOR_LIST_THAT_DONT_RETURN(V) \ 115 116namespace vixl { 117 118// The Visitor interface. Disassembler and simulator (and other tools) 119// must provide implementations for all of these functions. 120class DecoderVisitor { 121 public: 122 enum VisitorConstness { 123 kConstVisitor, 124 kNonConstVisitor 125 }; 126 explicit DecoderVisitor(VisitorConstness constness = kConstVisitor) 127 : constness_(constness) {} 128 129 virtual ~DecoderVisitor() {} 130 131 #define DECLARE(A) virtual void Visit##A(const Instruction* instr) = 0; 132 VISITOR_LIST(DECLARE) 133 #undef DECLARE 134 135 bool IsConstVisitor() const { return constness_ == kConstVisitor; } 136 Instruction* MutableInstruction(const Instruction* instr) { 137 VIXL_ASSERT(!IsConstVisitor()); 138 return const_cast<Instruction*>(instr); 139 } 140 141 private: 142 const VisitorConstness constness_; 143}; 144 145 146class Decoder { 147 public: 148 Decoder() {} 149 150 // Top-level wrappers around the actual decoding function. 151 void Decode(const Instruction* instr) { 152 std::list<DecoderVisitor*>::iterator it; 153 for (it = visitors_.begin(); it != visitors_.end(); it++) { 154 VIXL_ASSERT((*it)->IsConstVisitor()); 155 } 156 DecodeInstruction(instr); 157 } 158 void Decode(Instruction* instr) { 159 DecodeInstruction(const_cast<const Instruction*>(instr)); 160 } 161 162 // Register a new visitor class with the decoder. 163 // Decode() will call the corresponding visitor method from all registered 164 // visitor classes when decoding reaches the leaf node of the instruction 165 // decode tree. 166 // Visitors are called in order. 167 // A visitor can be registered multiple times. 168 // 169 // d.AppendVisitor(V1); 170 // d.AppendVisitor(V2); 171 // d.PrependVisitor(V2); 172 // d.AppendVisitor(V3); 173 // 174 // d.Decode(i); 175 // 176 // will call in order visitor methods in V2, V1, V2, V3. 177 void AppendVisitor(DecoderVisitor* visitor); 178 void PrependVisitor(DecoderVisitor* visitor); 179 // These helpers register `new_visitor` before or after the first instance of 180 // `registered_visiter` in the list. 181 // So if 182 // V1, V2, V1, V2 183 // are registered in this order in the decoder, calls to 184 // d.InsertVisitorAfter(V3, V1); 185 // d.InsertVisitorBefore(V4, V2); 186 // will yield the order 187 // V1, V3, V4, V2, V1, V2 188 // 189 // For more complex modifications of the order of registered visitors, one can 190 // directly access and modify the list of visitors via the `visitors()' 191 // accessor. 192 void InsertVisitorBefore(DecoderVisitor* new_visitor, 193 DecoderVisitor* registered_visitor); 194 void InsertVisitorAfter(DecoderVisitor* new_visitor, 195 DecoderVisitor* registered_visitor); 196 197 // Remove all instances of a previously registered visitor class from the list 198 // of visitors stored by the decoder. 199 void RemoveVisitor(DecoderVisitor* visitor); 200 201 #define DECLARE(A) void Visit##A(const Instruction* instr); 202 VISITOR_LIST(DECLARE) 203 #undef DECLARE 204 205 206 std::list<DecoderVisitor*>* visitors() { return &visitors_; } 207 208 private: 209 // Decodes an instruction and calls the visitor functions registered with the 210 // Decoder class. 211 void DecodeInstruction(const Instruction* instr); 212 213 // Decode the PC relative addressing instruction, and call the corresponding 214 // visitors. 215 // On entry, instruction bits 27:24 = 0x0. 216 void DecodePCRelAddressing(const Instruction* instr); 217 218 // Decode the add/subtract immediate instruction, and call the correspoding 219 // visitors. 220 // On entry, instruction bits 27:24 = 0x1. 221 void DecodeAddSubImmediate(const Instruction* instr); 222 223 // Decode the branch, system command, and exception generation parts of 224 // the instruction tree, and call the corresponding visitors. 225 // On entry, instruction bits 27:24 = {0x4, 0x5, 0x6, 0x7}. 226 void DecodeBranchSystemException(const Instruction* instr); 227 228 // Decode the load and store parts of the instruction tree, and call 229 // the corresponding visitors. 230 // On entry, instruction bits 27:24 = {0x8, 0x9, 0xC, 0xD}. 231 void DecodeLoadStore(const Instruction* instr); 232 233 // Decode the logical immediate and move wide immediate parts of the 234 // instruction tree, and call the corresponding visitors. 235 // On entry, instruction bits 27:24 = 0x2. 236 void DecodeLogical(const Instruction* instr); 237 238 // Decode the bitfield and extraction parts of the instruction tree, 239 // and call the corresponding visitors. 240 // On entry, instruction bits 27:24 = 0x3. 241 void DecodeBitfieldExtract(const Instruction* instr); 242 243 // Decode the data processing parts of the instruction tree, and call the 244 // corresponding visitors. 245 // On entry, instruction bits 27:24 = {0x1, 0xA, 0xB}. 246 void DecodeDataProcessing(const Instruction* instr); 247 248 // Decode the floating point parts of the instruction tree, and call the 249 // corresponding visitors. 250 // On entry, instruction bits 27:24 = {0xE, 0xF}. 251 void DecodeFP(const Instruction* instr); 252 253 // Decode the Advanced SIMD (NEON) load/store part of the instruction tree, 254 // and call the corresponding visitors. 255 // On entry, instruction bits 29:25 = 0x6. 256 void DecodeNEONLoadStore(const Instruction* instr); 257 258 // Decode the Advanced SIMD (NEON) vector data processing part of the 259 // instruction tree, and call the corresponding visitors. 260 // On entry, instruction bits 28:25 = 0x7. 261 void DecodeNEONVectorDataProcessing(const Instruction* instr); 262 263 // Decode the Advanced SIMD (NEON) scalar data processing part of the 264 // instruction tree, and call the corresponding visitors. 265 // On entry, instruction bits 28:25 = 0xF. 266 void DecodeNEONScalarDataProcessing(const Instruction* instr); 267 268 private: 269 // Visitors are registered in a list. 270 std::list<DecoderVisitor*> visitors_; 271}; 272 273} // namespace vixl 274 275#endif // VIXL_A64_DECODER_A64_H_ 276