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Diffstat (limited to 'src/disas/libvixl/a64/decoder-a64.h')
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diff --git a/src/disas/libvixl/a64/decoder-a64.h b/src/disas/libvixl/a64/decoder-a64.h new file mode 100644 index 0000000..fd08d6c --- /dev/null +++ b/src/disas/libvixl/a64/decoder-a64.h @@ -0,0 +1,239 @@ +// Copyright 2013, ARM Limited +// All rights reserved. +// +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are met: +// +// * Redistributions of source code must retain the above copyright notice, +// this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above copyright notice, +// this list of conditions and the following disclaimer in the documentation +// and/or other materials provided with the distribution. +// * Neither the name of ARM Limited nor the names of its contributors may be +// used to endorse or promote products derived from this software without +// specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS CONTRIBUTORS "AS IS" AND +// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED +// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE +// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE +// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR +// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER +// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, +// OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +#ifndef VIXL_A64_DECODER_A64_H_ +#define VIXL_A64_DECODER_A64_H_ + +#include <list> + +#include "globals.h" +#include "a64/instructions-a64.h" + + +// List macro containing all visitors needed by the decoder class. + +#define VISITOR_LIST(V) \ + V(PCRelAddressing) \ + V(AddSubImmediate) \ + V(LogicalImmediate) \ + V(MoveWideImmediate) \ + V(Bitfield) \ + V(Extract) \ + V(UnconditionalBranch) \ + V(UnconditionalBranchToRegister) \ + V(CompareBranch) \ + V(TestBranch) \ + V(ConditionalBranch) \ + V(System) \ + V(Exception) \ + V(LoadStorePairPostIndex) \ + V(LoadStorePairOffset) \ + V(LoadStorePairPreIndex) \ + V(LoadStorePairNonTemporal) \ + V(LoadLiteral) \ + V(LoadStoreUnscaledOffset) \ + V(LoadStorePostIndex) \ + V(LoadStorePreIndex) \ + V(LoadStoreRegisterOffset) \ + V(LoadStoreUnsignedOffset) \ + V(LoadStoreExclusive) \ + V(LogicalShifted) \ + V(AddSubShifted) \ + V(AddSubExtended) \ + V(AddSubWithCarry) \ + V(ConditionalCompareRegister) \ + V(ConditionalCompareImmediate) \ + V(ConditionalSelect) \ + V(DataProcessing1Source) \ + V(DataProcessing2Source) \ + V(DataProcessing3Source) \ + V(FPCompare) \ + V(FPConditionalCompare) \ + V(FPConditionalSelect) \ + V(FPImmediate) \ + V(FPDataProcessing1Source) \ + V(FPDataProcessing2Source) \ + V(FPDataProcessing3Source) \ + V(FPIntegerConvert) \ + V(FPFixedPointConvert) \ + V(Unallocated) \ + V(Unimplemented) + +namespace vixl { + +// The Visitor interface. Disassembler and simulator (and other tools) +// must provide implementations for all of these functions. +class DecoderVisitor { + public: + enum VisitorConstness { + kConstVisitor, + kNonConstVisitor + }; + explicit DecoderVisitor(VisitorConstness constness = kConstVisitor) + : constness_(constness) {} + + virtual ~DecoderVisitor() {} + + #define DECLARE(A) virtual void Visit##A(const Instruction* instr) = 0; + VISITOR_LIST(DECLARE) + #undef DECLARE + + bool IsConstVisitor() const { return constness_ == kConstVisitor; } + Instruction* MutableInstruction(const Instruction* instr) { + VIXL_ASSERT(!IsConstVisitor()); + return const_cast<Instruction*>(instr); + } + + private: + const VisitorConstness constness_; +}; + + +class Decoder { + public: + Decoder() {} + + // Top-level wrappers around the actual decoding function. + void Decode(const Instruction* instr) { + std::list<DecoderVisitor*>::iterator it; + for (it = visitors_.begin(); it != visitors_.end(); it++) { + VIXL_ASSERT((*it)->IsConstVisitor()); + } + DecodeInstruction(instr); + } + void Decode(Instruction* instr) { + DecodeInstruction(const_cast<const Instruction*>(instr)); + } + + // Register a new visitor class with the decoder. + // Decode() will call the corresponding visitor method from all registered + // visitor classes when decoding reaches the leaf node of the instruction + // decode tree. + // Visitors are called in order. + // A visitor can be registered multiple times. + // + // d.AppendVisitor(V1); + // d.AppendVisitor(V2); + // d.PrependVisitor(V2); + // d.AppendVisitor(V3); + // + // d.Decode(i); + // + // will call in order visitor methods in V2, V1, V2, V3. + void AppendVisitor(DecoderVisitor* visitor); + void PrependVisitor(DecoderVisitor* visitor); + // These helpers register `new_visitor` before or after the first instance of + // `registered_visiter` in the list. + // So if + // V1, V2, V1, V2 + // are registered in this order in the decoder, calls to + // d.InsertVisitorAfter(V3, V1); + // d.InsertVisitorBefore(V4, V2); + // will yield the order + // V1, V3, V4, V2, V1, V2 + // + // For more complex modifications of the order of registered visitors, one can + // directly access and modify the list of visitors via the `visitors()' + // accessor. + void InsertVisitorBefore(DecoderVisitor* new_visitor, + DecoderVisitor* registered_visitor); + void InsertVisitorAfter(DecoderVisitor* new_visitor, + DecoderVisitor* registered_visitor); + + // Remove all instances of a previously registered visitor class from the list + // of visitors stored by the decoder. + void RemoveVisitor(DecoderVisitor* visitor); + + #define DECLARE(A) void Visit##A(const Instruction* instr); + VISITOR_LIST(DECLARE) + #undef DECLARE + + + std::list<DecoderVisitor*>* visitors() { return &visitors_; } + + private: + // Decodes an instruction and calls the visitor functions registered with the + // Decoder class. + void DecodeInstruction(const Instruction* instr); + + // Decode the PC relative addressing instruction, and call the corresponding + // visitors. + // On entry, instruction bits 27:24 = 0x0. + void DecodePCRelAddressing(const Instruction* instr); + + // Decode the add/subtract immediate instruction, and call the correspoding + // visitors. + // On entry, instruction bits 27:24 = 0x1. + void DecodeAddSubImmediate(const Instruction* instr); + + // Decode the branch, system command, and exception generation parts of + // the instruction tree, and call the corresponding visitors. + // On entry, instruction bits 27:24 = {0x4, 0x5, 0x6, 0x7}. + void DecodeBranchSystemException(const Instruction* instr); + + // Decode the load and store parts of the instruction tree, and call + // the corresponding visitors. + // On entry, instruction bits 27:24 = {0x8, 0x9, 0xC, 0xD}. + void DecodeLoadStore(const Instruction* instr); + + // Decode the logical immediate and move wide immediate parts of the + // instruction tree, and call the corresponding visitors. + // On entry, instruction bits 27:24 = 0x2. + void DecodeLogical(const Instruction* instr); + + // Decode the bitfield and extraction parts of the instruction tree, + // and call the corresponding visitors. + // On entry, instruction bits 27:24 = 0x3. + void DecodeBitfieldExtract(const Instruction* instr); + + // Decode the data processing parts of the instruction tree, and call the + // corresponding visitors. + // On entry, instruction bits 27:24 = {0x1, 0xA, 0xB}. + void DecodeDataProcessing(const Instruction* instr); + + // Decode the floating point parts of the instruction tree, and call the + // corresponding visitors. + // On entry, instruction bits 27:24 = {0xE, 0xF}. + void DecodeFP(const Instruction* instr); + + // Decode the Advanced SIMD (NEON) load/store part of the instruction tree, + // and call the corresponding visitors. + // On entry, instruction bits 29:25 = 0x6. + void DecodeAdvSIMDLoadStore(const Instruction* instr); + + // Decode the Advanced SIMD (NEON) data processing part of the instruction + // tree, and call the corresponding visitors. + // On entry, instruction bits 27:25 = 0x7. + void DecodeAdvSIMDDataProcessing(const Instruction* instr); + + private: + // Visitors are registered in a list. + std::list<DecoderVisitor*> visitors_; +}; + +} // namespace vixl + +#endif // VIXL_A64_DECODER_A64_H_ |
