| //===- X86DisassemblerTables.cpp - Disassembler tables ----------*- C++ -*-===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file is part of the X86 Disassembler Emitter. |
| // It contains the implementation of the disassembler tables. |
| // Documentation for the disassembler emitter in general can be found in |
| // X86DisasemblerEmitter.h. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "X86DisassemblerShared.h" |
| #include "X86DisassemblerTables.h" |
| |
| #include "TableGenBackend.h" |
| #include "llvm/ADT/STLExtras.h" |
| #include "llvm/Support/ErrorHandling.h" |
| #include "llvm/Support/Format.h" |
| |
| using namespace llvm; |
| using namespace X86Disassembler; |
| |
| /// inheritsFrom - Indicates whether all instructions in one class also belong |
| /// to another class. |
| /// |
| /// @param child - The class that may be the subset |
| /// @param parent - The class that may be the superset |
| /// @return - True if child is a subset of parent, false otherwise. |
| static inline bool inheritsFrom(InstructionContext child, |
| InstructionContext parent) { |
| if (child == parent) |
| return true; |
| |
| switch (parent) { |
| case IC: |
| return true; |
| case IC_64BIT: |
| return(inheritsFrom(child, IC_64BIT_REXW) || |
| inheritsFrom(child, IC_64BIT_OPSIZE) || |
| inheritsFrom(child, IC_64BIT_XD) || |
| inheritsFrom(child, IC_64BIT_XS)); |
| case IC_OPSIZE: |
| return(inheritsFrom(child, IC_64BIT_OPSIZE)); |
| case IC_XD: |
| return(inheritsFrom(child, IC_64BIT_XD) || |
| inheritsFrom(child, IC_VEX_XD)); |
| case IC_XS: |
| return(inheritsFrom(child, IC_64BIT_XS) || |
| inheritsFrom(child, IC_VEX_XS)); |
| case IC_64BIT_REXW: |
| return(inheritsFrom(child, IC_64BIT_REXW_XS) || |
| inheritsFrom(child, IC_64BIT_REXW_XD) || |
| inheritsFrom(child, IC_64BIT_REXW_OPSIZE)); |
| case IC_64BIT_OPSIZE: |
| return(inheritsFrom(child, IC_64BIT_REXW_OPSIZE)); |
| case IC_64BIT_XD: |
| return(inheritsFrom(child, IC_64BIT_REXW_XD)); |
| case IC_64BIT_XS: |
| return(inheritsFrom(child, IC_64BIT_REXW_XS)); |
| case IC_64BIT_REXW_XD: |
| return false; |
| case IC_64BIT_REXW_XS: |
| return false; |
| case IC_64BIT_REXW_OPSIZE: |
| return false; |
| case IC_VEX: |
| return(inheritsFrom(child, IC_VEX_XS) || |
| inheritsFrom(child, IC_VEX_XD) || |
| inheritsFrom(child, IC_VEX_L) || |
| inheritsFrom(child, IC_VEX_W) || |
| inheritsFrom(child, IC_VEX_OPSIZE)); |
| case IC_VEX_XS: |
| return(inheritsFrom(child, IC_VEX_L_XS) || |
| inheritsFrom(child, IC_VEX_W_XS)); |
| case IC_VEX_XD: |
| return(inheritsFrom(child, IC_VEX_L_XD) || |
| inheritsFrom(child, IC_VEX_W_XD)); |
| case IC_VEX_L: |
| return(inheritsFrom(child, IC_VEX_L_XS) || |
| inheritsFrom(child, IC_VEX_L_XD)); |
| case IC_VEX_L_XS: |
| return false; |
| case IC_VEX_L_XD: |
| return false; |
| case IC_VEX_W: |
| return(inheritsFrom(child, IC_VEX_W_XS) || |
| inheritsFrom(child, IC_VEX_W_XD) || |
| inheritsFrom(child, IC_VEX_W_OPSIZE)); |
| case IC_VEX_W_XS: |
| return false; |
| case IC_VEX_W_XD: |
| return false; |
| case IC_VEX_OPSIZE: |
| return inheritsFrom(child, IC_VEX_W_OPSIZE); |
| default: |
| return false; |
| } |
| } |
| |
| /// outranks - Indicates whether, if an instruction has two different applicable |
| /// classes, which class should be preferred when performing decode. This |
| /// imposes a total ordering (ties are resolved toward "lower") |
| /// |
| /// @param upper - The class that may be preferable |
| /// @param lower - The class that may be less preferable |
| /// @return - True if upper is to be preferred, false otherwise. |
| static inline bool outranks(InstructionContext upper, |
| InstructionContext lower) { |
| assert(upper < IC_max); |
| assert(lower < IC_max); |
| |
| #define ENUM_ENTRY(n, r, d) r, |
| static int ranks[IC_max] = { |
| INSTRUCTION_CONTEXTS |
| }; |
| #undef ENUM_ENTRY |
| |
| return (ranks[upper] > ranks[lower]); |
| } |
| |
| /// stringForContext - Returns a string containing the name of a particular |
| /// InstructionContext, usually for diagnostic purposes. |
| /// |
| /// @param insnContext - The instruction class to transform to a string. |
| /// @return - A statically-allocated string constant that contains the |
| /// name of the instruction class. |
| static inline const char* stringForContext(InstructionContext insnContext) { |
| switch (insnContext) { |
| default: |
| llvm_unreachable("Unhandled instruction class"); |
| #define ENUM_ENTRY(n, r, d) case n: return #n; break; |
| INSTRUCTION_CONTEXTS |
| #undef ENUM_ENTRY |
| } |
| |
| return 0; |
| } |
| |
| /// stringForOperandType - Like stringForContext, but for OperandTypes. |
| static inline const char* stringForOperandType(OperandType type) { |
| switch (type) { |
| default: |
| llvm_unreachable("Unhandled type"); |
| #define ENUM_ENTRY(i, d) case i: return #i; |
| TYPES |
| #undef ENUM_ENTRY |
| } |
| } |
| |
| /// stringForOperandEncoding - like stringForContext, but for |
| /// OperandEncodings. |
| static inline const char* stringForOperandEncoding(OperandEncoding encoding) { |
| switch (encoding) { |
| default: |
| llvm_unreachable("Unhandled encoding"); |
| #define ENUM_ENTRY(i, d) case i: return #i; |
| ENCODINGS |
| #undef ENUM_ENTRY |
| } |
| } |
| |
| void DisassemblerTables::emitOneID(raw_ostream &o, |
| uint32_t &i, |
| InstrUID id, |
| bool addComma) const { |
| if (id) |
| o.indent(i * 2) << format("0x%hx", id); |
| else |
| o.indent(i * 2) << 0; |
| |
| if (addComma) |
| o << ", "; |
| else |
| o << " "; |
| |
| o << "/* "; |
| o << InstructionSpecifiers[id].name; |
| o << "*/"; |
| |
| o << "\n"; |
| } |
| |
| /// emitEmptyTable - Emits the modRMEmptyTable, which is used as a ID table by |
| /// all ModR/M decisions for instructions that are invalid for all possible |
| /// ModR/M byte values. |
| /// |
| /// @param o - The output stream on which to emit the table. |
| /// @param i - The indentation level for that output stream. |
| static void emitEmptyTable(raw_ostream &o, uint32_t &i) |
| { |
| o.indent(i * 2) << "static const InstrUID modRMEmptyTable[1] = { 0 };\n"; |
| o << "\n"; |
| } |
| |
| /// getDecisionType - Determines whether a ModRM decision with 255 entries can |
| /// be compacted by eliminating redundant information. |
| /// |
| /// @param decision - The decision to be compacted. |
| /// @return - The compactest available representation for the decision. |
| static ModRMDecisionType getDecisionType(ModRMDecision &decision) |
| { |
| bool satisfiesOneEntry = true; |
| bool satisfiesSplitRM = true; |
| |
| uint16_t index; |
| |
| for (index = 0; index < 256; ++index) { |
| if (decision.instructionIDs[index] != decision.instructionIDs[0]) |
| satisfiesOneEntry = false; |
| |
| if (((index & 0xc0) == 0xc0) && |
| (decision.instructionIDs[index] != decision.instructionIDs[0xc0])) |
| satisfiesSplitRM = false; |
| |
| if (((index & 0xc0) != 0xc0) && |
| (decision.instructionIDs[index] != decision.instructionIDs[0x00])) |
| satisfiesSplitRM = false; |
| } |
| |
| if (satisfiesOneEntry) |
| return MODRM_ONEENTRY; |
| |
| if (satisfiesSplitRM) |
| return MODRM_SPLITRM; |
| |
| return MODRM_FULL; |
| } |
| |
| /// stringForDecisionType - Returns a statically-allocated string corresponding |
| /// to a particular decision type. |
| /// |
| /// @param dt - The decision type. |
| /// @return - A pointer to the statically-allocated string (e.g., |
| /// "MODRM_ONEENTRY" for MODRM_ONEENTRY). |
| static const char* stringForDecisionType(ModRMDecisionType dt) |
| { |
| #define ENUM_ENTRY(n) case n: return #n; |
| switch (dt) { |
| default: |
| llvm_unreachable("Unknown decision type"); |
| MODRMTYPES |
| }; |
| #undef ENUM_ENTRY |
| } |
| |
| /// stringForModifierType - Returns a statically-allocated string corresponding |
| /// to an opcode modifier type. |
| /// |
| /// @param mt - The modifier type. |
| /// @return - A pointer to the statically-allocated string (e.g., |
| /// "MODIFIER_NONE" for MODIFIER_NONE). |
| static const char* stringForModifierType(ModifierType mt) |
| { |
| #define ENUM_ENTRY(n) case n: return #n; |
| switch(mt) { |
| default: |
| llvm_unreachable("Unknown modifier type"); |
| MODIFIER_TYPES |
| }; |
| #undef ENUM_ENTRY |
| } |
| |
| DisassemblerTables::DisassemblerTables() { |
| unsigned i; |
| |
| for (i = 0; i < array_lengthof(Tables); i++) { |
| Tables[i] = new ContextDecision; |
| memset(Tables[i], 0, sizeof(ContextDecision)); |
| } |
| |
| HasConflicts = false; |
| } |
| |
| DisassemblerTables::~DisassemblerTables() { |
| unsigned i; |
| |
| for (i = 0; i < array_lengthof(Tables); i++) |
| delete Tables[i]; |
| } |
| |
| void DisassemblerTables::emitModRMDecision(raw_ostream &o1, |
| raw_ostream &o2, |
| uint32_t &i1, |
| uint32_t &i2, |
| ModRMDecision &decision) |
| const { |
| static uint64_t sTableNumber = 0; |
| uint64_t thisTableNumber = sTableNumber; |
| ModRMDecisionType dt = getDecisionType(decision); |
| uint16_t index; |
| |
| if (dt == MODRM_ONEENTRY && decision.instructionIDs[0] == 0) |
| { |
| o2.indent(i2) << "{ /* ModRMDecision */" << "\n"; |
| i2++; |
| |
| o2.indent(i2) << stringForDecisionType(dt) << "," << "\n"; |
| o2.indent(i2) << "modRMEmptyTable"; |
| |
| i2--; |
| o2.indent(i2) << "}"; |
| return; |
| } |
| |
| o1.indent(i1) << "static const InstrUID modRMTable" << thisTableNumber; |
| |
| switch (dt) { |
| default: |
| llvm_unreachable("Unknown decision type"); |
| case MODRM_ONEENTRY: |
| o1 << "[1]"; |
| break; |
| case MODRM_SPLITRM: |
| o1 << "[2]"; |
| break; |
| case MODRM_FULL: |
| o1 << "[256]"; |
| break; |
| } |
| |
| o1 << " = {" << "\n"; |
| i1++; |
| |
| switch (dt) { |
| default: |
| llvm_unreachable("Unknown decision type"); |
| case MODRM_ONEENTRY: |
| emitOneID(o1, i1, decision.instructionIDs[0], false); |
| break; |
| case MODRM_SPLITRM: |
| emitOneID(o1, i1, decision.instructionIDs[0x00], true); // mod = 0b00 |
| emitOneID(o1, i1, decision.instructionIDs[0xc0], false); // mod = 0b11 |
| break; |
| case MODRM_FULL: |
| for (index = 0; index < 256; ++index) |
| emitOneID(o1, i1, decision.instructionIDs[index], index < 255); |
| break; |
| } |
| |
| i1--; |
| o1.indent(i1) << "};" << "\n"; |
| o1 << "\n"; |
| |
| o2.indent(i2) << "{ /* struct ModRMDecision */" << "\n"; |
| i2++; |
| |
| o2.indent(i2) << stringForDecisionType(dt) << "," << "\n"; |
| o2.indent(i2) << "modRMTable" << sTableNumber << "\n"; |
| |
| i2--; |
| o2.indent(i2) << "}"; |
| |
| ++sTableNumber; |
| } |
| |
| void DisassemblerTables::emitOpcodeDecision( |
| raw_ostream &o1, |
| raw_ostream &o2, |
| uint32_t &i1, |
| uint32_t &i2, |
| OpcodeDecision &decision) const { |
| uint16_t index; |
| |
| o2.indent(i2) << "{ /* struct OpcodeDecision */" << "\n"; |
| i2++; |
| o2.indent(i2) << "{" << "\n"; |
| i2++; |
| |
| for (index = 0; index < 256; ++index) { |
| o2.indent(i2); |
| |
| o2 << "/* 0x" << format("%02hhx", index) << " */" << "\n"; |
| |
| emitModRMDecision(o1, o2, i1, i2, decision.modRMDecisions[index]); |
| |
| if (index < 255) |
| o2 << ","; |
| |
| o2 << "\n"; |
| } |
| |
| i2--; |
| o2.indent(i2) << "}" << "\n"; |
| i2--; |
| o2.indent(i2) << "}" << "\n"; |
| } |
| |
| void DisassemblerTables::emitContextDecision( |
| raw_ostream &o1, |
| raw_ostream &o2, |
| uint32_t &i1, |
| uint32_t &i2, |
| ContextDecision &decision, |
| const char* name) const { |
| o2.indent(i2) << "static const struct ContextDecision " << name << " = {\n"; |
| i2++; |
| o2.indent(i2) << "{ /* opcodeDecisions */" << "\n"; |
| i2++; |
| |
| unsigned index; |
| |
| for (index = 0; index < IC_max; ++index) { |
| o2.indent(i2) << "/* "; |
| o2 << stringForContext((InstructionContext)index); |
| o2 << " */"; |
| o2 << "\n"; |
| |
| emitOpcodeDecision(o1, o2, i1, i2, decision.opcodeDecisions[index]); |
| |
| if (index + 1 < IC_max) |
| o2 << ", "; |
| } |
| |
| i2--; |
| o2.indent(i2) << "}" << "\n"; |
| i2--; |
| o2.indent(i2) << "};" << "\n"; |
| } |
| |
| void DisassemblerTables::emitInstructionInfo(raw_ostream &o, uint32_t &i) |
| const { |
| o.indent(i * 2) << "static const struct InstructionSpecifier "; |
| o << INSTRUCTIONS_STR "[" << InstructionSpecifiers.size() << "] = {\n"; |
| |
| i++; |
| |
| uint16_t numInstructions = InstructionSpecifiers.size(); |
| uint16_t index, operandIndex; |
| |
| for (index = 0; index < numInstructions; ++index) { |
| o.indent(i * 2) << "{ /* " << index << " */" << "\n"; |
| i++; |
| |
| o.indent(i * 2) << |
| stringForModifierType(InstructionSpecifiers[index].modifierType); |
| o << "," << "\n"; |
| |
| o.indent(i * 2) << "0x"; |
| o << format("%02hhx", (uint16_t)InstructionSpecifiers[index].modifierBase); |
| o << "," << "\n"; |
| |
| o.indent(i * 2) << "{" << "\n"; |
| i++; |
| |
| for (operandIndex = 0; operandIndex < X86_MAX_OPERANDS; ++operandIndex) { |
| o.indent(i * 2) << "{ "; |
| o << stringForOperandEncoding(InstructionSpecifiers[index] |
| .operands[operandIndex] |
| .encoding); |
| o << ", "; |
| o << stringForOperandType(InstructionSpecifiers[index] |
| .operands[operandIndex] |
| .type); |
| o << " }"; |
| |
| if (operandIndex < X86_MAX_OPERANDS - 1) |
| o << ","; |
| |
| o << "\n"; |
| } |
| |
| i--; |
| o.indent(i * 2) << "}," << "\n"; |
| |
| o.indent(i * 2) << "\"" << InstructionSpecifiers[index].name << "\""; |
| o << "\n"; |
| |
| i--; |
| o.indent(i * 2) << "}"; |
| |
| if (index + 1 < numInstructions) |
| o << ","; |
| |
| o << "\n"; |
| } |
| |
| i--; |
| o.indent(i * 2) << "};" << "\n"; |
| } |
| |
| void DisassemblerTables::emitContextTable(raw_ostream &o, uint32_t &i) const { |
| uint16_t index; |
| |
| o.indent(i * 2) << "static const InstructionContext " CONTEXTS_STR |
| "[256] = {\n"; |
| i++; |
| |
| for (index = 0; index < 256; ++index) { |
| o.indent(i * 2); |
| |
| if ((index & ATTR_VEXL) && (index & ATTR_OPSIZE)) |
| o << "IC_VEX_L_OPSIZE"; |
| else if ((index & ATTR_VEXL) && (index & ATTR_XD)) |
| o << "IC_VEX_L_XD"; |
| else if ((index & ATTR_VEXL) && (index & ATTR_XS)) |
| o << "IC_VEX_L_XS"; |
| else if ((index & ATTR_VEX) && (index & ATTR_REXW) && (index & ATTR_OPSIZE)) |
| o << "IC_VEX_W_OPSIZE"; |
| else if ((index & ATTR_VEX) && (index & ATTR_REXW) && (index & ATTR_XD)) |
| o << "IC_VEX_W_XD"; |
| else if ((index & ATTR_VEX) && (index & ATTR_REXW) && (index & ATTR_XS)) |
| o << "IC_VEX_W_XS"; |
| else if (index & ATTR_VEXL) |
| o << "IC_VEX_L"; |
| else if ((index & ATTR_VEX) && (index & ATTR_REXW)) |
| o << "IC_VEX_W"; |
| else if ((index & ATTR_VEX) && (index & ATTR_OPSIZE)) |
| o << "IC_VEX_OPSIZE"; |
| else if ((index & ATTR_VEX) && (index & ATTR_XD)) |
| o << "IC_VEX_XD"; |
| else if ((index & ATTR_VEX) && (index & ATTR_XS)) |
| o << "IC_VEX_XS"; |
| else if ((index & ATTR_64BIT) && (index & ATTR_REXW) && (index & ATTR_XS)) |
| o << "IC_64BIT_REXW_XS"; |
| else if ((index & ATTR_64BIT) && (index & ATTR_REXW) && (index & ATTR_XD)) |
| o << "IC_64BIT_REXW_XD"; |
| else if ((index & ATTR_64BIT) && (index & ATTR_REXW) && |
| (index & ATTR_OPSIZE)) |
| o << "IC_64BIT_REXW_OPSIZE"; |
| else if ((index & ATTR_64BIT) && (index & ATTR_XS)) |
| o << "IC_64BIT_XS"; |
| else if ((index & ATTR_64BIT) && (index & ATTR_XD)) |
| o << "IC_64BIT_XD"; |
| else if ((index & ATTR_64BIT) && (index & ATTR_OPSIZE)) |
| o << "IC_64BIT_OPSIZE"; |
| else if ((index & ATTR_64BIT) && (index & ATTR_REXW)) |
| o << "IC_64BIT_REXW"; |
| else if ((index & ATTR_64BIT)) |
| o << "IC_64BIT"; |
| else if (index & ATTR_XS) |
| o << "IC_XS"; |
| else if (index & ATTR_XD) |
| o << "IC_XD"; |
| else if (index & ATTR_OPSIZE) |
| o << "IC_OPSIZE"; |
| else if (index & ATTR_VEX) |
| o << "IC_VEX"; |
| else |
| o << "IC"; |
| |
| if (index < 255) |
| o << ","; |
| else |
| o << " "; |
| |
| o << " /* " << index << " */"; |
| |
| o << "\n"; |
| } |
| |
| i--; |
| o.indent(i * 2) << "};" << "\n"; |
| } |
| |
| void DisassemblerTables::emitContextDecisions(raw_ostream &o1, |
| raw_ostream &o2, |
| uint32_t &i1, |
| uint32_t &i2) |
| const { |
| emitContextDecision(o1, o2, i1, i2, *Tables[0], ONEBYTE_STR); |
| emitContextDecision(o1, o2, i1, i2, *Tables[1], TWOBYTE_STR); |
| emitContextDecision(o1, o2, i1, i2, *Tables[2], THREEBYTE38_STR); |
| emitContextDecision(o1, o2, i1, i2, *Tables[3], THREEBYTE3A_STR); |
| emitContextDecision(o1, o2, i1, i2, *Tables[4], THREEBYTEA6_STR); |
| emitContextDecision(o1, o2, i1, i2, *Tables[5], THREEBYTEA7_STR); |
| } |
| |
| void DisassemblerTables::emit(raw_ostream &o) const { |
| uint32_t i1 = 0; |
| uint32_t i2 = 0; |
| |
| std::string s1; |
| std::string s2; |
| |
| raw_string_ostream o1(s1); |
| raw_string_ostream o2(s2); |
| |
| emitInstructionInfo(o, i2); |
| o << "\n"; |
| |
| emitContextTable(o, i2); |
| o << "\n"; |
| |
| emitEmptyTable(o1, i1); |
| emitContextDecisions(o1, o2, i1, i2); |
| |
| o << o1.str(); |
| o << "\n"; |
| o << o2.str(); |
| o << "\n"; |
| o << "\n"; |
| } |
| |
| void DisassemblerTables::setTableFields(ModRMDecision &decision, |
| const ModRMFilter &filter, |
| InstrUID uid, |
| uint8_t opcode) { |
| unsigned index; |
| |
| for (index = 0; index < 256; ++index) { |
| if (filter.accepts(index)) { |
| if (decision.instructionIDs[index] == uid) |
| continue; |
| |
| if (decision.instructionIDs[index] != 0) { |
| InstructionSpecifier &newInfo = |
| InstructionSpecifiers[uid]; |
| InstructionSpecifier &previousInfo = |
| InstructionSpecifiers[decision.instructionIDs[index]]; |
| |
| if(newInfo.filtered) |
| continue; // filtered instructions get lowest priority |
| |
| if(previousInfo.name == "NOOP") |
| continue; // special case for XCHG32ar and NOOP |
| |
| if (outranks(previousInfo.insnContext, newInfo.insnContext)) |
| continue; |
| |
| if (previousInfo.insnContext == newInfo.insnContext && |
| !previousInfo.filtered) { |
| errs() << "Error: Primary decode conflict: "; |
| errs() << newInfo.name << " would overwrite " << previousInfo.name; |
| errs() << "\n"; |
| errs() << "ModRM " << index << "\n"; |
| errs() << "Opcode " << (uint16_t)opcode << "\n"; |
| errs() << "Context " << stringForContext(newInfo.insnContext) << "\n"; |
| HasConflicts = true; |
| } |
| } |
| |
| decision.instructionIDs[index] = uid; |
| } |
| } |
| } |
| |
| void DisassemblerTables::setTableFields(OpcodeType type, |
| InstructionContext insnContext, |
| uint8_t opcode, |
| const ModRMFilter &filter, |
| InstrUID uid) { |
| unsigned index; |
| |
| ContextDecision &decision = *Tables[type]; |
| |
| for (index = 0; index < IC_max; ++index) { |
| if (inheritsFrom((InstructionContext)index, |
| InstructionSpecifiers[uid].insnContext)) |
| setTableFields(decision.opcodeDecisions[index].modRMDecisions[opcode], |
| filter, |
| uid, |
| opcode); |
| } |
| } |