/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ // Copyright 2011 the V8 project authors. 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 Google Inc. 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 AND 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 jit_mips32_Simulator_mips32_h #define jit_mips32_Simulator_mips32_h #ifdef JS_SIMULATOR_MIPS32 #include "jit/IonTypes.h" #include "threading/Thread.h" #include "vm/MutexIDs.h" namespace js { namespace jit { class Simulator; class Redirection; class CachePage; class AutoLockSimulator; const intptr_t kPointerAlignment = 4; const intptr_t kPointerAlignmentMask = kPointerAlignment - 1; const intptr_t kDoubleAlignment = 8; const intptr_t kDoubleAlignmentMask = kDoubleAlignment - 1; // Number of general purpose registers. const int kNumRegisters = 32; // In the simulator, the PC register is simulated as the 34th register. const int kPCRegister = 34; // Number coprocessor registers. const int kNumFPURegisters = 32; // FPU (coprocessor 1) control registers. Currently only FCSR is implemented. const int kFCSRRegister = 31; const int kInvalidFPUControlRegister = -1; const uint32_t kFPUInvalidResult = static_cast<uint32_t>(1 << 31) - 1; // FCSR constants. const uint32_t kFCSRInexactFlagBit = 2; const uint32_t kFCSRUnderflowFlagBit = 3; const uint32_t kFCSROverflowFlagBit = 4; const uint32_t kFCSRDivideByZeroFlagBit = 5; const uint32_t kFCSRInvalidOpFlagBit = 6; const uint32_t kFCSRInexactFlagMask = 1 << kFCSRInexactFlagBit; const uint32_t kFCSRUnderflowFlagMask = 1 << kFCSRUnderflowFlagBit; const uint32_t kFCSROverflowFlagMask = 1 << kFCSROverflowFlagBit; const uint32_t kFCSRDivideByZeroFlagMask = 1 << kFCSRDivideByZeroFlagBit; const uint32_t kFCSRInvalidOpFlagMask = 1 << kFCSRInvalidOpFlagBit; const uint32_t kFCSRFlagMask = kFCSRInexactFlagMask | kFCSRUnderflowFlagMask | kFCSROverflowFlagMask | kFCSRDivideByZeroFlagMask | kFCSRInvalidOpFlagMask; const uint32_t kFCSRExceptionFlagMask = kFCSRFlagMask ^ kFCSRInexactFlagMask; // On MIPS Simulator breakpoints can have different codes: // - Breaks between 0 and kMaxWatchpointCode are treated as simple watchpoints, // the simulator will run through them and print the registers. // - Breaks between kMaxWatchpointCode and kMaxStopCode are treated as stop() // instructions (see Assembler::stop()). // - Breaks larger than kMaxStopCode are simple breaks, dropping you into the // debugger. const uint32_t kMaxWatchpointCode = 31; const uint32_t kMaxStopCode = 127; // ----------------------------------------------------------------------------- // Utility functions typedef uint32_t Instr; class SimInstruction; class Simulator { friend class Redirection; friend class MipsDebugger; friend class AutoLockSimulatorCache; public: // Registers are declared in order. See "See MIPS Run Linux" chapter 2. enum Register { no_reg = -1, zero_reg = 0, at, v0, v1, a0, a1, a2, a3, t0, t1, t2, t3, t4, t5, t6, t7, s0, s1, s2, s3, s4, s5, s6, s7, t8, t9, k0, k1, gp, sp, s8, ra, // LO, HI, and pc. LO, HI, pc, // pc must be the last register. kNumSimuRegisters, // aliases fp = s8 }; // Coprocessor registers. enum FPURegister { f0, f1, f2, f3, f4, f5, f6, f7, f8, f9, f10, f11, f12, f13, f14, f15, // f12 and f14 are arguments FPURegisters. f16, f17, f18, f19, f20, f21, f22, f23, f24, f25, f26, f27, f28, f29, f30, f31, kNumFPURegisters }; // Returns nullptr on OOM. static Simulator* Create(JSContext* cx); static void Destroy(Simulator* simulator); // Constructor/destructor are for internal use only; use the static methods above. Simulator(); ~Simulator(); // The currently executing Simulator instance. Potentially there can be one // for each native thread. static Simulator* Current(); static inline uintptr_t StackLimit() { return Simulator::Current()->stackLimit(); } uintptr_t* addressOfStackLimit(); // Accessors for register state. Reading the pc value adheres to the MIPS // architecture specification and is off by a 8 from the currently executing // instruction. void setRegister(int reg, int32_t value); int32_t getRegister(int reg) const; double getDoubleFromRegisterPair(int reg); // Same for FPURegisters. void setFpuRegister(int fpureg, int32_t value); void setFpuRegisterFloat(int fpureg, float value); void setFpuRegisterFloat(int fpureg, int64_t value); void setFpuRegisterDouble(int fpureg, double value); void setFpuRegisterDouble(int fpureg, int64_t value); int32_t getFpuRegister(int fpureg) const; int64_t getFpuRegisterLong(int fpureg) const; float getFpuRegisterFloat(int fpureg) const; double getFpuRegisterDouble(int fpureg) const; void setFCSRBit(uint32_t cc, bool value); bool testFCSRBit(uint32_t cc); bool setFCSRRoundError(double original, double rounded); // Special case of set_register and get_register to access the raw PC value. void set_pc(int32_t value); int32_t get_pc() const; template <typename T> T get_pc_as() const { return reinterpret_cast<T>(get_pc()); } void set_resume_pc(void* value) { resume_pc_ = int32_t(value); } // Accessor to the internal simulator stack area. uintptr_t stackLimit() const; bool overRecursed(uintptr_t newsp = 0) const; bool overRecursedWithExtra(uint32_t extra) const; // Executes MIPS instructions until the PC reaches end_sim_pc. template<bool enableStopSimAt> void execute(); // Sets up the simulator state and grabs the result on return. int32_t call(uint8_t* entry, int argument_count, ...); // Push an address onto the JS stack. uintptr_t pushAddress(uintptr_t address); // Pop an address from the JS stack. uintptr_t popAddress(); // Debugger input. void setLastDebuggerInput(char* input); char* lastDebuggerInput() { return lastDebuggerInput_; } // ICache checking. static void FlushICache(void* start, size_t size); // Returns true if pc register contains one of the 'SpecialValues' defined // below (bad_ra, end_sim_pc). bool has_bad_pc() const; private: enum SpecialValues { // Known bad pc value to ensure that the simulator does not execute // without being properly setup. bad_ra = -1, // A pc value used to signal the simulator to stop execution. Generally // the ra is set to this value on transition from native C code to // simulated execution, so that the simulator can "return" to the native // C code. end_sim_pc = -2, // Unpredictable value. Unpredictable = 0xbadbeaf }; bool init(); // Unsupported instructions use Format to print an error and stop execution. void format(SimInstruction* instr, const char* format); // Read and write memory. inline uint32_t readBU(uint32_t addr); inline int32_t readB(uint32_t addr); inline void writeB(uint32_t addr, uint8_t value); inline void writeB(uint32_t addr, int8_t value); inline uint16_t readHU(uint32_t addr, SimInstruction* instr); inline int16_t readH(uint32_t addr, SimInstruction* instr); // Note: Overloaded on the sign of the value. inline void writeH(uint32_t addr, uint16_t value, SimInstruction* instr); inline void writeH(uint32_t addr, int16_t value, SimInstruction* instr); inline int readW(uint32_t addr, SimInstruction* instr); inline void writeW(uint32_t addr, int value, SimInstruction* instr); inline double readD(uint32_t addr, SimInstruction* instr); inline void writeD(uint32_t addr, double value, SimInstruction* instr); // Executing is handled based on the instruction type. void decodeTypeRegister(SimInstruction* instr); // Helper function for decodeTypeRegister. void configureTypeRegister(SimInstruction* instr, int32_t& alu_out, int64_t& i64hilo, uint64_t& u64hilo, int32_t& next_pc, int32_t& return_addr_reg, bool& do_interrupt); void decodeTypeImmediate(SimInstruction* instr); void decodeTypeJump(SimInstruction* instr); // Used for breakpoints and traps. void softwareInterrupt(SimInstruction* instr); // Stop helper functions. bool isWatchpoint(uint32_t code); void printWatchpoint(uint32_t code); void handleStop(uint32_t code, SimInstruction* instr); bool isStopInstruction(SimInstruction* instr); bool isEnabledStop(uint32_t code); void enableStop(uint32_t code); void disableStop(uint32_t code); void increaseStopCounter(uint32_t code); void printStopInfo(uint32_t code); // Executes one instruction. void instructionDecode(SimInstruction* instr); // Execute one instruction placed in a branch delay slot. void branchDelayInstructionDecode(SimInstruction* instr); public: static bool ICacheCheckingEnabled; static int StopSimAt; // Runtime call support. static void* RedirectNativeFunction(void* nativeFunction, ABIFunctionType type); private: enum Exception { kNone, kIntegerOverflow, kIntegerUnderflow, kDivideByZero, kNumExceptions }; int16_t exceptions[kNumExceptions]; // Exceptions. void signalExceptions(); // Handle arguments and return value for runtime FP functions. void getFpArgs(double* x, double* y, int32_t* z); void getFpFromStack(int32_t* stack, double* x); void setCallResultDouble(double result); void setCallResultFloat(float result); void setCallResult(int64_t res); void callInternal(uint8_t* entry); // Architecture state. // Registers. int32_t registers_[kNumSimuRegisters]; // Coprocessor Registers. int32_t FPUregisters_[kNumFPURegisters]; // FPU control register. uint32_t FCSR_; // Simulator support. char* stack_; uintptr_t stackLimit_; bool pc_modified_; int icount_; int break_count_; int32_t resume_pc_; // Debugger input. char* lastDebuggerInput_; // Registered breakpoints. SimInstruction* break_pc_; Instr break_instr_; // A stop is watched if its code is less than kNumOfWatchedStops. // Only watched stops support enabling/disabling and the counter feature. static const uint32_t kNumOfWatchedStops = 256; // Stop is disabled if bit 31 is set. static const uint32_t kStopDisabledBit = 1U << 31; // A stop is enabled, meaning the simulator will stop when meeting the // instruction, if bit 31 of watchedStops_[code].count is unset. // The value watchedStops_[code].count & ~(1 << 31) indicates how many times // the breakpoint was hit or gone through. struct StopCountAndDesc { uint32_t count_; char* desc_; }; StopCountAndDesc watchedStops_[kNumOfWatchedStops]; private: // ICache checking. struct ICacheHasher { typedef void* Key; typedef void* Lookup; static HashNumber hash(const Lookup& l); static bool match(const Key& k, const Lookup& l); }; public: typedef HashMap<void*, CachePage*, ICacheHasher, SystemAllocPolicy> ICacheMap; private: // This lock creates a critical section around 'redirection_' and // 'icache_', which are referenced both by the execution engine // and by the off-thread compiler (see Redirection::Get in the cpp file). Mutex cacheLock_; #ifdef DEBUG mozilla::Maybe<Thread::Id> cacheLockHolder_; #endif Redirection* redirection_; ICacheMap icache_; public: ICacheMap& icache() { // Technically we need the lock to access the innards of the // icache, not to take its address, but the latter condition // serves as a useful complement to the former. MOZ_ASSERT(cacheLockHolder_.isSome()); return icache_; } Redirection* redirection() const { MOZ_ASSERT(cacheLockHolder_.isSome()); return redirection_; } void setRedirection(js::jit::Redirection* redirection) { MOZ_ASSERT(cacheLockHolder_.isSome()); redirection_ = redirection; } }; #define JS_CHECK_SIMULATOR_RECURSION_WITH_EXTRA(cx, extra, onerror) \ JS_BEGIN_MACRO \ if (cx->mainThread().simulator()->overRecursedWithExtra(extra)) { \ js::ReportOverRecursed(cx); \ onerror; \ } \ JS_END_MACRO } // namespace jit } // namespace js #endif /* JS_SIMULATOR_MIPS32 */ #endif /* jit_mips32_Simulator_mips32_h */