// Copyright (c) 1994-2006 Sun Microsystems Inc. // 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. // // - Redistribution 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 Sun Microsystems or the names of 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. // The original source code covered by the above license above has been // modified significantly by Google Inc. // Copyright 2011 the V8 project authors. All rights reserved. // A light-weight ARM Assembler // Generates user mode instructions for the ARM architecture up to version 5 #ifndef V8_ARM_ASSEMBLER_ARM_H_ #define V8_ARM_ASSEMBLER_ARM_H_ #include #include "assembler.h" #include "constants-arm.h" #include "serialize.h" namespace v8 { namespace internal { // CPU Registers. // // 1) We would prefer to use an enum, but enum values are assignment- // compatible with int, which has caused code-generation bugs. // // 2) We would prefer to use a class instead of a struct but we don't like // the register initialization to depend on the particular initialization // order (which appears to be different on OS X, Linux, and Windows for the // installed versions of C++ we tried). Using a struct permits C-style // "initialization". Also, the Register objects cannot be const as this // forces initialization stubs in MSVC, making us dependent on initialization // order. // // 3) By not using an enum, we are possibly preventing the compiler from // doing certain constant folds, which may significantly reduce the // code generated for some assembly instructions (because they boil down // to a few constants). If this is a problem, we could change the code // such that we use an enum in optimized mode, and the struct in debug // mode. This way we get the compile-time error checking in debug mode // and best performance in optimized code. // Core register struct Register { static const int kNumRegisters = 16; static const int kNumAllocatableRegisters = 8; static const int kSizeInBytes = 4; static int ToAllocationIndex(Register reg) { ASSERT(reg.code() < kNumAllocatableRegisters); return reg.code(); } static Register FromAllocationIndex(int index) { ASSERT(index >= 0 && index < kNumAllocatableRegisters); return from_code(index); } static const char* AllocationIndexToString(int index) { ASSERT(index >= 0 && index < kNumAllocatableRegisters); const char* const names[] = { "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", }; return names[index]; } static Register from_code(int code) { Register r = { code }; return r; } bool is_valid() const { return 0 <= code_ && code_ < kNumRegisters; } bool is(Register reg) const { return code_ == reg.code_; } int code() const { ASSERT(is_valid()); return code_; } int bit() const { ASSERT(is_valid()); return 1 << code_; } void set_code(int code) { code_ = code; ASSERT(is_valid()); } // Unfortunately we can't make this private in a struct. int code_; }; const Register no_reg = { -1 }; const Register r0 = { 0 }; const Register r1 = { 1 }; const Register r2 = { 2 }; const Register r3 = { 3 }; const Register r4 = { 4 }; const Register r5 = { 5 }; const Register r6 = { 6 }; const Register r7 = { 7 }; const Register r8 = { 8 }; // Used as context register. const Register r9 = { 9 }; // Used as lithium codegen scratch register. const Register r10 = { 10 }; // Used as roots register. const Register fp = { 11 }; const Register ip = { 12 }; const Register sp = { 13 }; const Register lr = { 14 }; const Register pc = { 15 }; // Single word VFP register. struct SwVfpRegister { bool is_valid() const { return 0 <= code_ && code_ < 32; } bool is(SwVfpRegister reg) const { return code_ == reg.code_; } int code() const { ASSERT(is_valid()); return code_; } int bit() const { ASSERT(is_valid()); return 1 << code_; } void split_code(int* vm, int* m) const { ASSERT(is_valid()); *m = code_ & 0x1; *vm = code_ >> 1; } int code_; }; // Double word VFP register. struct DwVfpRegister { // d0 has been excluded from allocation. This is following ia32 // where xmm0 is excluded. This should be revisited. // Currently d0 is used as a scratch register. // d1 has also been excluded from allocation to be used as a scratch // register as well. static const int kNumRegisters = 16; static const int kNumAllocatableRegisters = 15; static int ToAllocationIndex(DwVfpRegister reg) { ASSERT(reg.code() != 0); return reg.code() - 1; } static DwVfpRegister FromAllocationIndex(int index) { ASSERT(index >= 0 && index < kNumAllocatableRegisters); return from_code(index + 1); } static const char* AllocationIndexToString(int index) { ASSERT(index >= 0 && index < kNumAllocatableRegisters); const char* const names[] = { "d1", "d2", "d3", "d4", "d5", "d6", "d7", "d8", "d9", "d10", "d11", "d12", "d13", "d14", "d15" }; return names[index]; } static DwVfpRegister from_code(int code) { DwVfpRegister r = { code }; return r; } // Supporting d0 to d15, can be later extended to d31. bool is_valid() const { return 0 <= code_ && code_ < 16; } bool is(DwVfpRegister reg) const { return code_ == reg.code_; } SwVfpRegister low() const { SwVfpRegister reg; reg.code_ = code_ * 2; ASSERT(reg.is_valid()); return reg; } SwVfpRegister high() const { SwVfpRegister reg; reg.code_ = (code_ * 2) + 1; ASSERT(reg.is_valid()); return reg; } int code() const { ASSERT(is_valid()); return code_; } int bit() const { ASSERT(is_valid()); return 1 << code_; } void split_code(int* vm, int* m) const { ASSERT(is_valid()); *m = (code_ & 0x10) >> 4; *vm = code_ & 0x0F; } int code_; }; typedef DwVfpRegister DoubleRegister; // Support for the VFP registers s0 to s31 (d0 to d15). // Note that "s(N):s(N+1)" is the same as "d(N/2)". const SwVfpRegister s0 = { 0 }; const SwVfpRegister s1 = { 1 }; const SwVfpRegister s2 = { 2 }; const SwVfpRegister s3 = { 3 }; const SwVfpRegister s4 = { 4 }; const SwVfpRegister s5 = { 5 }; const SwVfpRegister s6 = { 6 }; const SwVfpRegister s7 = { 7 }; const SwVfpRegister s8 = { 8 }; const SwVfpRegister s9 = { 9 }; const SwVfpRegister s10 = { 10 }; const SwVfpRegister s11 = { 11 }; const SwVfpRegister s12 = { 12 }; const SwVfpRegister s13 = { 13 }; const SwVfpRegister s14 = { 14 }; const SwVfpRegister s15 = { 15 }; const SwVfpRegister s16 = { 16 }; const SwVfpRegister s17 = { 17 }; const SwVfpRegister s18 = { 18 }; const SwVfpRegister s19 = { 19 }; const SwVfpRegister s20 = { 20 }; const SwVfpRegister s21 = { 21 }; const SwVfpRegister s22 = { 22 }; const SwVfpRegister s23 = { 23 }; const SwVfpRegister s24 = { 24 }; const SwVfpRegister s25 = { 25 }; const SwVfpRegister s26 = { 26 }; const SwVfpRegister s27 = { 27 }; const SwVfpRegister s28 = { 28 }; const SwVfpRegister s29 = { 29 }; const SwVfpRegister s30 = { 30 }; const SwVfpRegister s31 = { 31 }; const DwVfpRegister no_dreg = { -1 }; const DwVfpRegister d0 = { 0 }; const DwVfpRegister d1 = { 1 }; const DwVfpRegister d2 = { 2 }; const DwVfpRegister d3 = { 3 }; const DwVfpRegister d4 = { 4 }; const DwVfpRegister d5 = { 5 }; const DwVfpRegister d6 = { 6 }; const DwVfpRegister d7 = { 7 }; const DwVfpRegister d8 = { 8 }; const DwVfpRegister d9 = { 9 }; const DwVfpRegister d10 = { 10 }; const DwVfpRegister d11 = { 11 }; const DwVfpRegister d12 = { 12 }; const DwVfpRegister d13 = { 13 }; const DwVfpRegister d14 = { 14 }; const DwVfpRegister d15 = { 15 }; // Coprocessor register struct CRegister { bool is_valid() const { return 0 <= code_ && code_ < 16; } bool is(CRegister creg) const { return code_ == creg.code_; } int code() const { ASSERT(is_valid()); return code_; } int bit() const { ASSERT(is_valid()); return 1 << code_; } // Unfortunately we can't make this private in a struct. int code_; }; const CRegister no_creg = { -1 }; const CRegister cr0 = { 0 }; const CRegister cr1 = { 1 }; const CRegister cr2 = { 2 }; const CRegister cr3 = { 3 }; const CRegister cr4 = { 4 }; const CRegister cr5 = { 5 }; const CRegister cr6 = { 6 }; const CRegister cr7 = { 7 }; const CRegister cr8 = { 8 }; const CRegister cr9 = { 9 }; const CRegister cr10 = { 10 }; const CRegister cr11 = { 11 }; const CRegister cr12 = { 12 }; const CRegister cr13 = { 13 }; const CRegister cr14 = { 14 }; const CRegister cr15 = { 15 }; // Coprocessor number enum Coprocessor { p0 = 0, p1 = 1, p2 = 2, p3 = 3, p4 = 4, p5 = 5, p6 = 6, p7 = 7, p8 = 8, p9 = 9, p10 = 10, p11 = 11, p12 = 12, p13 = 13, p14 = 14, p15 = 15 }; // ----------------------------------------------------------------------------- // Machine instruction Operands // Class Operand represents a shifter operand in data processing instructions class Operand BASE_EMBEDDED { public: // immediate INLINE(explicit Operand(int32_t immediate, RelocInfo::Mode rmode = RelocInfo::NONE)); INLINE(explicit Operand(const ExternalReference& f)); INLINE(explicit Operand(const char* s)); explicit Operand(Handle handle); INLINE(explicit Operand(Smi* value)); // rm INLINE(explicit Operand(Register rm)); // rm shift_imm explicit Operand(Register rm, ShiftOp shift_op, int shift_imm); // rm rs explicit Operand(Register rm, ShiftOp shift_op, Register rs); // Return true if this is a register operand. INLINE(bool is_reg() const); // Return true if this operand fits in one instruction so that no // 2-instruction solution with a load into the ip register is necessary. If // the instruction this operand is used for is a MOV or MVN instruction the // actual instruction to use is required for this calculation. For other // instructions instr is ignored. bool is_single_instruction(Instr instr = 0) const; bool must_use_constant_pool() const; inline int32_t immediate() const { ASSERT(!rm_.is_valid()); return imm32_; } Register rm() const { return rm_; } Register rs() const { return rs_; } ShiftOp shift_op() const { return shift_op_; } private: Register rm_; Register rs_; ShiftOp shift_op_; int shift_imm_; // valid if rm_ != no_reg && rs_ == no_reg int32_t imm32_; // valid if rm_ == no_reg RelocInfo::Mode rmode_; friend class Assembler; }; // Class MemOperand represents a memory operand in load and store instructions class MemOperand BASE_EMBEDDED { public: // [rn +/- offset] Offset/NegOffset // [rn +/- offset]! PreIndex/NegPreIndex // [rn], +/- offset PostIndex/NegPostIndex // offset is any signed 32-bit value; offset is first loaded to register ip if // it does not fit the addressing mode (12-bit unsigned and sign bit) explicit MemOperand(Register rn, int32_t offset = 0, AddrMode am = Offset); // [rn +/- rm] Offset/NegOffset // [rn +/- rm]! PreIndex/NegPreIndex // [rn], +/- rm PostIndex/NegPostIndex explicit MemOperand(Register rn, Register rm, AddrMode am = Offset); // [rn +/- rm shift_imm] Offset/NegOffset // [rn +/- rm shift_imm]! PreIndex/NegPreIndex // [rn], +/- rm shift_imm PostIndex/NegPostIndex explicit MemOperand(Register rn, Register rm, ShiftOp shift_op, int shift_imm, AddrMode am = Offset); void set_offset(int32_t offset) { ASSERT(rm_.is(no_reg)); offset_ = offset; } uint32_t offset() const { ASSERT(rm_.is(no_reg)); return offset_; } Register rn() const { return rn_; } Register rm() const { return rm_; } bool OffsetIsUint12Encodable() const { return offset_ >= 0 ? is_uint12(offset_) : is_uint12(-offset_); } private: Register rn_; // base Register rm_; // register offset int32_t offset_; // valid if rm_ == no_reg ShiftOp shift_op_; int shift_imm_; // valid if rm_ != no_reg && rs_ == no_reg AddrMode am_; // bits P, U, and W friend class Assembler; }; // CpuFeatures keeps track of which features are supported by the target CPU. // Supported features must be enabled by a Scope before use. class CpuFeatures : public AllStatic { public: // Detect features of the target CPU. Set safe defaults if the serializer // is enabled (snapshots must be portable). static void Probe(); // Check whether a feature is supported by the target CPU. static bool IsSupported(CpuFeature f) { ASSERT(initialized_); if (f == VFP3 && !FLAG_enable_vfp3) return false; return (supported_ & (1u << f)) != 0; } #ifdef DEBUG // Check whether a feature is currently enabled. static bool IsEnabled(CpuFeature f) { ASSERT(initialized_); Isolate* isolate = Isolate::UncheckedCurrent(); if (isolate == NULL) { // When no isolate is available, work as if we're running in // release mode. return IsSupported(f); } unsigned enabled = static_cast(isolate->enabled_cpu_features()); return (enabled & (1u << f)) != 0; } #endif // Enable a specified feature within a scope. class Scope BASE_EMBEDDED { #ifdef DEBUG public: explicit Scope(CpuFeature f) { unsigned mask = 1u << f; ASSERT(CpuFeatures::IsSupported(f)); ASSERT(!Serializer::enabled() || (CpuFeatures::found_by_runtime_probing_ & mask) == 0); isolate_ = Isolate::UncheckedCurrent(); old_enabled_ = 0; if (isolate_ != NULL) { old_enabled_ = static_cast(isolate_->enabled_cpu_features()); isolate_->set_enabled_cpu_features(old_enabled_ | mask); } } ~Scope() { ASSERT_EQ(Isolate::UncheckedCurrent(), isolate_); if (isolate_ != NULL) { isolate_->set_enabled_cpu_features(old_enabled_); } } private: Isolate* isolate_; unsigned old_enabled_; #else public: explicit Scope(CpuFeature f) {} #endif }; class TryForceFeatureScope BASE_EMBEDDED { public: explicit TryForceFeatureScope(CpuFeature f) : old_supported_(CpuFeatures::supported_) { if (CanForce()) { CpuFeatures::supported_ |= (1u << f); } } ~TryForceFeatureScope() { if (CanForce()) { CpuFeatures::supported_ = old_supported_; } } private: static bool CanForce() { // It's only safe to temporarily force support of CPU features // when there's only a single isolate, which is guaranteed when // the serializer is enabled. return Serializer::enabled(); } const unsigned old_supported_; }; private: #ifdef DEBUG static bool initialized_; #endif static unsigned supported_; static unsigned found_by_runtime_probing_; DISALLOW_COPY_AND_ASSIGN(CpuFeatures); }; extern const Instr kMovLrPc; extern const Instr kLdrPCMask; extern const Instr kLdrPCPattern; extern const Instr kBlxRegMask; extern const Instr kBlxRegPattern; extern const Instr kMovMvnMask; extern const Instr kMovMvnPattern; extern const Instr kMovMvnFlip; extern const Instr kMovLeaveCCMask; extern const Instr kMovLeaveCCPattern; extern const Instr kMovwMask; extern const Instr kMovwPattern; extern const Instr kMovwLeaveCCFlip; extern const Instr kCmpCmnMask; extern const Instr kCmpCmnPattern; extern const Instr kCmpCmnFlip; extern const Instr kAddSubFlip; extern const Instr kAndBicFlip; class Assembler : public AssemblerBase { public: // Create an assembler. Instructions and relocation information are emitted // into a buffer, with the instructions starting from the beginning and the // relocation information starting from the end of the buffer. See CodeDesc // for a detailed comment on the layout (globals.h). // // If the provided buffer is NULL, the assembler allocates and grows its own // buffer, and buffer_size determines the initial buffer size. The buffer is // owned by the assembler and deallocated upon destruction of the assembler. // // If the provided buffer is not NULL, the assembler uses the provided buffer // for code generation and assumes its size to be buffer_size. If the buffer // is too small, a fatal error occurs. No deallocation of the buffer is done // upon destruction of the assembler. Assembler(Isolate* isolate, void* buffer, int buffer_size); ~Assembler(); // Overrides the default provided by FLAG_debug_code. void set_emit_debug_code(bool value) { emit_debug_code_ = value; } // GetCode emits any pending (non-emitted) code and fills the descriptor // desc. GetCode() is idempotent; it returns the same result if no other // Assembler functions are invoked in between GetCode() calls. void GetCode(CodeDesc* desc); // Label operations & relative jumps (PPUM Appendix D) // // Takes a branch opcode (cc) and a label (L) and generates // either a backward branch or a forward branch and links it // to the label fixup chain. Usage: // // Label L; // unbound label // j(cc, &L); // forward branch to unbound label // bind(&L); // bind label to the current pc // j(cc, &L); // backward branch to bound label // bind(&L); // illegal: a label may be bound only once // // Note: The same Label can be used for forward and backward branches // but it may be bound only once. void bind(Label* L); // binds an unbound label L to the current code position // Returns the branch offset to the given label from the current code position // Links the label to the current position if it is still unbound // Manages the jump elimination optimization if the second parameter is true. int branch_offset(Label* L, bool jump_elimination_allowed); // Puts a labels target address at the given position. // The high 8 bits are set to zero. void label_at_put(Label* L, int at_offset); // Return the address in the constant pool of the code target address used by // the branch/call instruction at pc. INLINE(static Address target_address_address_at(Address pc)); // Read/Modify the code target address in the branch/call instruction at pc. INLINE(static Address target_address_at(Address pc)); INLINE(static void set_target_address_at(Address pc, Address target)); // This sets the branch destination (which is in the constant pool on ARM). // This is for calls and branches within generated code. inline static void set_target_at(Address constant_pool_entry, Address target); // This sets the branch destination (which is in the constant pool on ARM). // This is for calls and branches to runtime code. inline static void set_external_target_at(Address constant_pool_entry, Address target) { set_target_at(constant_pool_entry, target); } // Here we are patching the address in the constant pool, not the actual call // instruction. The address in the constant pool is the same size as a // pointer. static const int kCallTargetSize = kPointerSize; static const int kExternalTargetSize = kPointerSize; // Size of an instruction. static const int kInstrSize = sizeof(Instr); // Distance between the instruction referring to the address of the call // target and the return address. #ifdef USE_BLX // Call sequence is: // ldr ip, [pc, #...] @ call address // blx ip // @ return address static const int kCallTargetAddressOffset = 2 * kInstrSize; #else // Call sequence is: // mov lr, pc // ldr pc, [pc, #...] @ call address // @ return address static const int kCallTargetAddressOffset = kInstrSize; #endif // Distance between start of patched return sequence and the emitted address // to jump to. #ifdef USE_BLX // Patched return sequence is: // ldr ip, [pc, #0] @ emited address and start // blx ip static const int kPatchReturnSequenceAddressOffset = 0 * kInstrSize; #else // Patched return sequence is: // mov lr, pc @ start of sequence // ldr pc, [pc, #-4] @ emited address static const int kPatchReturnSequenceAddressOffset = kInstrSize; #endif // Distance between start of patched debug break slot and the emitted address // to jump to. #ifdef USE_BLX // Patched debug break slot code is: // ldr ip, [pc, #0] @ emited address and start // blx ip static const int kPatchDebugBreakSlotAddressOffset = 0 * kInstrSize; #else // Patched debug break slot code is: // mov lr, pc @ start of sequence // ldr pc, [pc, #-4] @ emited address static const int kPatchDebugBreakSlotAddressOffset = kInstrSize; #endif // Difference between address of current opcode and value read from pc // register. static const int kPcLoadDelta = 8; static const int kJSReturnSequenceInstructions = 4; static const int kDebugBreakSlotInstructions = 3; static const int kDebugBreakSlotLength = kDebugBreakSlotInstructions * kInstrSize; // --------------------------------------------------------------------------- // Code generation // Insert the smallest number of nop instructions // possible to align the pc offset to a multiple // of m. m must be a power of 2 (>= 4). void Align(int m); // Aligns code to something that's optimal for a jump target for the platform. void CodeTargetAlign(); // Branch instructions void b(int branch_offset, Condition cond = al); void bl(int branch_offset, Condition cond = al); void blx(int branch_offset); // v5 and above void blx(Register target, Condition cond = al); // v5 and above void bx(Register target, Condition cond = al); // v5 and above, plus v4t // Convenience branch instructions using labels void b(Label* L, Condition cond = al) { b(branch_offset(L, cond == al), cond); } void b(Condition cond, Label* L) { b(branch_offset(L, cond == al), cond); } void bl(Label* L, Condition cond = al) { bl(branch_offset(L, false), cond); } void bl(Condition cond, Label* L) { bl(branch_offset(L, false), cond); } void blx(Label* L) { blx(branch_offset(L, false)); } // v5 and above // Data-processing instructions void and_(Register dst, Register src1, const Operand& src2, SBit s = LeaveCC, Condition cond = al); void eor(Register dst, Register src1, const Operand& src2, SBit s = LeaveCC, Condition cond = al); void sub(Register dst, Register src1, const Operand& src2, SBit s = LeaveCC, Condition cond = al); void sub(Register dst, Register src1, Register src2, SBit s = LeaveCC, Condition cond = al) { sub(dst, src1, Operand(src2), s, cond); } void rsb(Register dst, Register src1, const Operand& src2, SBit s = LeaveCC, Condition cond = al); void add(Register dst, Register src1, const Operand& src2, SBit s = LeaveCC, Condition cond = al); void add(Register dst, Register src1, Register src2, SBit s = LeaveCC, Condition cond = al) { add(dst, src1, Operand(src2), s, cond); } void adc(Register dst, Register src1, const Operand& src2, SBit s = LeaveCC, Condition cond = al); void sbc(Register dst, Register src1, const Operand& src2, SBit s = LeaveCC, Condition cond = al); void rsc(Register dst, Register src1, const Operand& src2, SBit s = LeaveCC, Condition cond = al); void tst(Register src1, const Operand& src2, Condition cond = al); void tst(Register src1, Register src2, Condition cond = al) { tst(src1, Operand(src2), cond); } void teq(Register src1, const Operand& src2, Condition cond = al); void cmp(Register src1, const Operand& src2, Condition cond = al); void cmp(Register src1, Register src2, Condition cond = al) { cmp(src1, Operand(src2), cond); } void cmp_raw_immediate(Register src1, int raw_immediate, Condition cond = al); void cmn(Register src1, const Operand& src2, Condition cond = al); void orr(Register dst, Register src1, const Operand& src2, SBit s = LeaveCC, Condition cond = al); void orr(Register dst, Register src1, Register src2, SBit s = LeaveCC, Condition cond = al) { orr(dst, src1, Operand(src2), s, cond); } void mov(Register dst, const Operand& src, SBit s = LeaveCC, Condition cond = al); void mov(Register dst, Register src, SBit s = LeaveCC, Condition cond = al) { mov(dst, Operand(src), s, cond); } // ARMv7 instructions for loading a 32 bit immediate in two instructions. // This may actually emit a different mov instruction, but on an ARMv7 it // is guaranteed to only emit one instruction. void movw(Register reg, uint32_t immediate, Condition cond = al); // The constant for movt should be in the range 0-0xffff. void movt(Register reg, uint32_t immediate, Condition cond = al); void bic(Register dst, Register src1, const Operand& src2, SBit s = LeaveCC, Condition cond = al); void mvn(Register dst, const Operand& src, SBit s = LeaveCC, Condition cond = al); // Multiply instructions void mla(Register dst, Register src1, Register src2, Register srcA, SBit s = LeaveCC, Condition cond = al); void mul(Register dst, Register src1, Register src2, SBit s = LeaveCC, Condition cond = al); void smlal(Register dstL, Register dstH, Register src1, Register src2, SBit s = LeaveCC, Condition cond = al); void smull(Register dstL, Register dstH, Register src1, Register src2, SBit s = LeaveCC, Condition cond = al); void umlal(Register dstL, Register dstH, Register src1, Register src2, SBit s = LeaveCC, Condition cond = al); void umull(Register dstL, Register dstH, Register src1, Register src2, SBit s = LeaveCC, Condition cond = al); // Miscellaneous arithmetic instructions void clz(Register dst, Register src, Condition cond = al); // v5 and above // Saturating instructions. v6 and above. // Unsigned saturate. // // Saturate an optionally shifted signed value to an unsigned range. // // usat dst, #satpos, src // usat dst, #satpos, src, lsl #sh // usat dst, #satpos, src, asr #sh // // Register dst will contain: // // 0, if s < 0 // (1 << satpos) - 1, if s > ((1 << satpos) - 1) // s, otherwise // // where s is the contents of src after shifting (if used.) void usat(Register dst, int satpos, const Operand& src, Condition cond = al); // Bitfield manipulation instructions. v7 and above. void ubfx(Register dst, Register src, int lsb, int width, Condition cond = al); void sbfx(Register dst, Register src, int lsb, int width, Condition cond = al); void bfc(Register dst, int lsb, int width, Condition cond = al); void bfi(Register dst, Register src, int lsb, int width, Condition cond = al); // Status register access instructions void mrs(Register dst, SRegister s, Condition cond = al); void msr(SRegisterFieldMask fields, const Operand& src, Condition cond = al); // Load/Store instructions void ldr(Register dst, const MemOperand& src, Condition cond = al); void str(Register src, const MemOperand& dst, Condition cond = al); void ldrb(Register dst, const MemOperand& src, Condition cond = al); void strb(Register src, const MemOperand& dst, Condition cond = al); void ldrh(Register dst, const MemOperand& src, Condition cond = al); void strh(Register src, const MemOperand& dst, Condition cond = al); void ldrsb(Register dst, const MemOperand& src, Condition cond = al); void ldrsh(Register dst, const MemOperand& src, Condition cond = al); void ldrd(Register dst1, Register dst2, const MemOperand& src, Condition cond = al); void strd(Register src1, Register src2, const MemOperand& dst, Condition cond = al); // Load/Store multiple instructions void ldm(BlockAddrMode am, Register base, RegList dst, Condition cond = al); void stm(BlockAddrMode am, Register base, RegList src, Condition cond = al); // Exception-generating instructions and debugging support void stop(const char* msg, Condition cond = al, int32_t code = kDefaultStopCode); void bkpt(uint32_t imm16); // v5 and above void svc(uint32_t imm24, Condition cond = al); // Coprocessor instructions void cdp(Coprocessor coproc, int opcode_1, CRegister crd, CRegister crn, CRegister crm, int opcode_2, Condition cond = al); void cdp2(Coprocessor coproc, int opcode_1, CRegister crd, CRegister crn, CRegister crm, int opcode_2); // v5 and above void mcr(Coprocessor coproc, int opcode_1, Register rd, CRegister crn, CRegister crm, int opcode_2 = 0, Condition cond = al); void mcr2(Coprocessor coproc, int opcode_1, Register rd, CRegister crn, CRegister crm, int opcode_2 = 0); // v5 and above void mrc(Coprocessor coproc, int opcode_1, Register rd, CRegister crn, CRegister crm, int opcode_2 = 0, Condition cond = al); void mrc2(Coprocessor coproc, int opcode_1, Register rd, CRegister crn, CRegister crm, int opcode_2 = 0); // v5 and above void ldc(Coprocessor coproc, CRegister crd, const MemOperand& src, LFlag l = Short, Condition cond = al); void ldc(Coprocessor coproc, CRegister crd, Register base, int option, LFlag l = Short, Condition cond = al); void ldc2(Coprocessor coproc, CRegister crd, const MemOperand& src, LFlag l = Short); // v5 and above void ldc2(Coprocessor coproc, CRegister crd, Register base, int option, LFlag l = Short); // v5 and above // Support for VFP. // All these APIs support S0 to S31 and D0 to D15. // Currently these APIs do not support extended D registers, i.e, D16 to D31. // However, some simple modifications can allow // these APIs to support D16 to D31. void vldr(const DwVfpRegister dst, const Register base, int offset, const Condition cond = al); void vldr(const DwVfpRegister dst, const MemOperand& src, const Condition cond = al); void vldr(const SwVfpRegister dst, const Register base, int offset, const Condition cond = al); void vldr(const SwVfpRegister dst, const MemOperand& src, const Condition cond = al); void vstr(const DwVfpRegister src, const Register base, int offset, const Condition cond = al); void vstr(const DwVfpRegister src, const MemOperand& dst, const Condition cond = al); void vstr(const SwVfpRegister src, const Register base, int offset, const Condition cond = al); void vstr(const SwVfpRegister src, const MemOperand& dst, const Condition cond = al); void vldm(BlockAddrMode am, Register base, DwVfpRegister first, DwVfpRegister last, Condition cond = al); void vstm(BlockAddrMode am, Register base, DwVfpRegister first, DwVfpRegister last, Condition cond = al); void vldm(BlockAddrMode am, Register base, SwVfpRegister first, SwVfpRegister last, Condition cond = al); void vstm(BlockAddrMode am, Register base, SwVfpRegister first, SwVfpRegister last, Condition cond = al); void vmov(const DwVfpRegister dst, double imm, const Condition cond = al); void vmov(const SwVfpRegister dst, const SwVfpRegister src, const Condition cond = al); void vmov(const DwVfpRegister dst, const DwVfpRegister src, const Condition cond = al); void vmov(const DwVfpRegister dst, const Register src1, const Register src2, const Condition cond = al); void vmov(const Register dst1, const Register dst2, const DwVfpRegister src, const Condition cond = al); void vmov(const SwVfpRegister dst, const Register src, const Condition cond = al); void vmov(const Register dst, const SwVfpRegister src, const Condition cond = al); void vcvt_f64_s32(const DwVfpRegister dst, const SwVfpRegister src, VFPConversionMode mode = kDefaultRoundToZero, const Condition cond = al); void vcvt_f32_s32(const SwVfpRegister dst, const SwVfpRegister src, VFPConversionMode mode = kDefaultRoundToZero, const Condition cond = al); void vcvt_f64_u32(const DwVfpRegister dst, const SwVfpRegister src, VFPConversionMode mode = kDefaultRoundToZero, const Condition cond = al); void vcvt_s32_f64(const SwVfpRegister dst, const DwVfpRegister src, VFPConversionMode mode = kDefaultRoundToZero, const Condition cond = al); void vcvt_u32_f64(const SwVfpRegister dst, const DwVfpRegister src, VFPConversionMode mode = kDefaultRoundToZero, const Condition cond = al); void vcvt_f64_f32(const DwVfpRegister dst, const SwVfpRegister src, VFPConversionMode mode = kDefaultRoundToZero, const Condition cond = al); void vcvt_f32_f64(const SwVfpRegister dst, const DwVfpRegister src, VFPConversionMode mode = kDefaultRoundToZero, const Condition cond = al); void vneg(const DwVfpRegister dst, const DwVfpRegister src, const Condition cond = al); void vabs(const DwVfpRegister dst, const DwVfpRegister src, const Condition cond = al); void vadd(const DwVfpRegister dst, const DwVfpRegister src1, const DwVfpRegister src2, const Condition cond = al); void vsub(const DwVfpRegister dst, const DwVfpRegister src1, const DwVfpRegister src2, const Condition cond = al); void vmul(const DwVfpRegister dst, const DwVfpRegister src1, const DwVfpRegister src2, const Condition cond = al); void vdiv(const DwVfpRegister dst, const DwVfpRegister src1, const DwVfpRegister src2, const Condition cond = al); void vcmp(const DwVfpRegister src1, const DwVfpRegister src2, const Condition cond = al); void vcmp(const DwVfpRegister src1, const double src2, const Condition cond = al); void vmrs(const Register dst, const Condition cond = al); void vmsr(const Register dst, const Condition cond = al); void vsqrt(const DwVfpRegister dst, const DwVfpRegister src, const Condition cond = al); // Pseudo instructions // Different nop operations are used by the code generator to detect certain // states of the generated code. enum NopMarkerTypes { NON_MARKING_NOP = 0, DEBUG_BREAK_NOP, // IC markers. PROPERTY_ACCESS_INLINED, PROPERTY_ACCESS_INLINED_CONTEXT, PROPERTY_ACCESS_INLINED_CONTEXT_DONT_DELETE, // Helper values. LAST_CODE_MARKER, FIRST_IC_MARKER = PROPERTY_ACCESS_INLINED }; void nop(int type = 0); // 0 is the default non-marking type. void push(Register src, Condition cond = al) { str(src, MemOperand(sp, 4, NegPreIndex), cond); } void pop(Register dst, Condition cond = al) { ldr(dst, MemOperand(sp, 4, PostIndex), cond); } void pop() { add(sp, sp, Operand(kPointerSize)); } // Jump unconditionally to given label. void jmp(Label* L) { b(L, al); } // Check the code size generated from label to here. int InstructionsGeneratedSince(Label* l) { return (pc_offset() - l->pos()) / kInstrSize; } // Check whether an immediate fits an addressing mode 1 instruction. bool ImmediateFitsAddrMode1Instruction(int32_t imm32); // Class for scoping postponing the constant pool generation. class BlockConstPoolScope { public: explicit BlockConstPoolScope(Assembler* assem) : assem_(assem) { assem_->StartBlockConstPool(); } ~BlockConstPoolScope() { assem_->EndBlockConstPool(); } private: Assembler* assem_; DISALLOW_IMPLICIT_CONSTRUCTORS(BlockConstPoolScope); }; // Postpone the generation of the constant pool for the specified number of // instructions. void BlockConstPoolFor(int instructions); // Debugging // Mark address of the ExitJSFrame code. void RecordJSReturn(); // Mark address of a debug break slot. void RecordDebugBreakSlot(); // Record the AST id of the CallIC being compiled, so that it can be placed // in the relocation information. void RecordAstId(unsigned ast_id) { ast_id_for_reloc_info_ = ast_id; } // Record a comment relocation entry that can be used by a disassembler. // Use --code-comments to enable. void RecordComment(const char* msg); // Writes a single byte or word of data in the code stream. Used // for inline tables, e.g., jump-tables. The constant pool should be // emitted before any use of db and dd to ensure that constant pools // are not emitted as part of the tables generated. void db(uint8_t data); void dd(uint32_t data); int pc_offset() const { return pc_ - buffer_; } PositionsRecorder* positions_recorder() { return &positions_recorder_; } // Read/patch instructions static Instr instr_at(byte* pc) { return *reinterpret_cast(pc); } static void instr_at_put(byte* pc, Instr instr) { *reinterpret_cast(pc) = instr; } static Condition GetCondition(Instr instr); static bool IsBranch(Instr instr); static int GetBranchOffset(Instr instr); static bool IsLdrRegisterImmediate(Instr instr); static int GetLdrRegisterImmediateOffset(Instr instr); static Instr SetLdrRegisterImmediateOffset(Instr instr, int offset); static bool IsStrRegisterImmediate(Instr instr); static Instr SetStrRegisterImmediateOffset(Instr instr, int offset); static bool IsAddRegisterImmediate(Instr instr); static Instr SetAddRegisterImmediateOffset(Instr instr, int offset); static Register GetRd(Instr instr); static Register GetRn(Instr instr); static Register GetRm(Instr instr); static bool IsPush(Instr instr); static bool IsPop(Instr instr); static bool IsStrRegFpOffset(Instr instr); static bool IsLdrRegFpOffset(Instr instr); static bool IsStrRegFpNegOffset(Instr instr); static bool IsLdrRegFpNegOffset(Instr instr); static bool IsLdrPcImmediateOffset(Instr instr); static bool IsTstImmediate(Instr instr); static bool IsCmpRegister(Instr instr); static bool IsCmpImmediate(Instr instr); static Register GetCmpImmediateRegister(Instr instr); static int GetCmpImmediateRawImmediate(Instr instr); static bool IsNop(Instr instr, int type = NON_MARKING_NOP); // Buffer size and constant pool distance are checked together at regular // intervals of kBufferCheckInterval emitted bytes static const int kBufferCheckInterval = 1*KB/2; // Constants in pools are accessed via pc relative addressing, which can // reach +/-4KB thereby defining a maximum distance between the instruction // and the accessed constant. We satisfy this constraint by limiting the // distance between pools. static const int kMaxDistBetweenPools = 4*KB - 2*kBufferCheckInterval; static const int kMaxNumPRInfo = kMaxDistBetweenPools/kInstrSize; // Check if is time to emit a constant pool for pending reloc info entries void CheckConstPool(bool force_emit, bool require_jump); protected: // Relocation for a type-recording IC has the AST id added to it. This // member variable is a way to pass the information from the call site to // the relocation info. unsigned ast_id_for_reloc_info_; bool emit_debug_code() const { return emit_debug_code_; } int buffer_space() const { return reloc_info_writer.pos() - pc_; } // Read/patch instructions Instr instr_at(int pos) { return *reinterpret_cast(buffer_ + pos); } void instr_at_put(int pos, Instr instr) { *reinterpret_cast(buffer_ + pos) = instr; } // Decode branch instruction at pos and return branch target pos int target_at(int pos); // Patch branch instruction at pos to branch to given branch target pos void target_at_put(int pos, int target_pos); // Block the emission of the constant pool before pc_offset void BlockConstPoolBefore(int pc_offset) { if (no_const_pool_before_ < pc_offset) no_const_pool_before_ = pc_offset; } void StartBlockConstPool() { const_pool_blocked_nesting_++; } void EndBlockConstPool() { const_pool_blocked_nesting_--; } bool is_const_pool_blocked() const { return const_pool_blocked_nesting_ > 0; } private: // Code buffer: // The buffer into which code and relocation info are generated. byte* buffer_; int buffer_size_; // True if the assembler owns the buffer, false if buffer is external. bool own_buffer_; int next_buffer_check_; // pc offset of next buffer check // Code generation // The relocation writer's position is at least kGap bytes below the end of // the generated instructions. This is so that multi-instruction sequences do // not have to check for overflow. The same is true for writes of large // relocation info entries. static const int kGap = 32; byte* pc_; // the program counter; moves forward // Constant pool generation // Pools are emitted in the instruction stream, preferably after unconditional // jumps or after returns from functions (in dead code locations). // If a long code sequence does not contain unconditional jumps, it is // necessary to emit the constant pool before the pool gets too far from the // location it is accessed from. In this case, we emit a jump over the emitted // constant pool. // Constants in the pool may be addresses of functions that gets relocated; // if so, a relocation info entry is associated to the constant pool entry. // Repeated checking whether the constant pool should be emitted is rather // expensive. By default we only check again once a number of instructions // has been generated. That also means that the sizing of the buffers is not // an exact science, and that we rely on some slop to not overrun buffers. static const int kCheckConstIntervalInst = 32; static const int kCheckConstInterval = kCheckConstIntervalInst * kInstrSize; // Pools are emitted after function return and in dead code at (more or less) // regular intervals of kDistBetweenPools bytes static const int kDistBetweenPools = 1*KB; // Emission of the constant pool may be blocked in some code sequences. int const_pool_blocked_nesting_; // Block emission if this is not zero. int no_const_pool_before_; // Block emission before this pc offset. // Keep track of the last emitted pool to guarantee a maximal distance int last_const_pool_end_; // pc offset following the last constant pool // Relocation info generation // Each relocation is encoded as a variable size value static const int kMaxRelocSize = RelocInfoWriter::kMaxSize; RelocInfoWriter reloc_info_writer; // Relocation info records are also used during code generation as temporary // containers for constants and code target addresses until they are emitted // to the constant pool. These pending relocation info records are temporarily // stored in a separate buffer until a constant pool is emitted. // If every instruction in a long sequence is accessing the pool, we need one // pending relocation entry per instruction. RelocInfo prinfo_[kMaxNumPRInfo]; // the buffer of pending relocation info int num_prinfo_; // number of pending reloc info entries in the buffer // The bound position, before this we cannot do instruction elimination. int last_bound_pos_; // Code emission inline void CheckBuffer(); void GrowBuffer(); inline void emit(Instr x); // Instruction generation void addrmod1(Instr instr, Register rn, Register rd, const Operand& x); void addrmod2(Instr instr, Register rd, const MemOperand& x); void addrmod3(Instr instr, Register rd, const MemOperand& x); void addrmod4(Instr instr, Register rn, RegList rl); void addrmod5(Instr instr, CRegister crd, const MemOperand& x); // Labels void print(Label* L); void bind_to(Label* L, int pos); void link_to(Label* L, Label* appendix); void next(Label* L); // Record reloc info for current pc_ void RecordRelocInfo(RelocInfo::Mode rmode, intptr_t data = 0); friend class RegExpMacroAssemblerARM; friend class RelocInfo; friend class CodePatcher; friend class BlockConstPoolScope; PositionsRecorder positions_recorder_; bool emit_debug_code_; friend class PositionsRecorder; friend class EnsureSpace; }; class EnsureSpace BASE_EMBEDDED { public: explicit EnsureSpace(Assembler* assembler) { assembler->CheckBuffer(); } }; } } // namespace v8::internal #endif // V8_ARM_ASSEMBLER_ARM_H_