| // Copyright 2011 Google Inc. All Rights Reserved. |
| |
| #include "dex_instruction.h" |
| |
| namespace art { |
| |
| const char* const Instruction::kInstructionNames[] = { |
| #define INSTRUCTION_NAME(o, c, pname, f, r, i, a, v) pname, |
| #include "dex_instruction_list.h" |
| DEX_INSTRUCTION_LIST(INSTRUCTION_NAME) |
| #undef DEX_INSTRUCTION_LIST |
| #undef INSTRUCTION_NAME |
| }; |
| |
| Instruction::InstructionFormat const Instruction::kInstructionFormats[] = { |
| #define INSTRUCTION_FORMAT(o, c, p, format, r, i, a, v) format, |
| #include "dex_instruction_list.h" |
| DEX_INSTRUCTION_LIST(INSTRUCTION_FORMAT) |
| #undef DEX_INSTRUCTION_LIST |
| #undef INSTRUCTION_FORMAT |
| }; |
| |
| int const Instruction::kInstructionFlags[] = { |
| #define INSTRUCTION_FLAGS(o, c, p, f, r, i, flags, v) flags, |
| #include "dex_instruction_list.h" |
| DEX_INSTRUCTION_LIST(INSTRUCTION_FLAGS) |
| #undef DEX_INSTRUCTION_LIST |
| #undef INSTRUCTION_FLAGS |
| }; |
| |
| int const Instruction::kInstructionVerifyFlags[] = { |
| #define INSTRUCTION_VERIFY_FLAGS(o, c, p, f, r, i, a, vflags) vflags, |
| #include "dex_instruction_list.h" |
| DEX_INSTRUCTION_LIST(INSTRUCTION_VERIFY_FLAGS) |
| #undef DEX_INSTRUCTION_LIST |
| #undef INSTRUCTION_VERIFY_FLAGS |
| }; |
| |
| /* |
| * Handy macros for helping decode instructions. |
| */ |
| #define FETCH(_offset) (insns[(_offset)]) |
| #define FETCH_u4(_offset) (fetch_u4_impl((_offset), insns)) |
| #define INST_A(_insn) (((uint16_t)(_insn) >> 8) & 0x0f) |
| #define INST_B(_insn) ((uint16_t)(_insn) >> 12) |
| #define INST_AA(_insn) ((_insn) >> 8) |
| |
| /* Helper for FETCH_u4, above. */ |
| static inline uint32_t fetch_u4_impl(uint32_t offset, const uint16_t* insns) { |
| return insns[offset] | ((uint32_t) insns[offset+1] << 16); |
| } |
| |
| void Instruction::Decode(uint32_t &vA, uint32_t &vB, uint64_t &vB_wide, uint32_t &vC, uint32_t arg[]) const { |
| const uint16_t* insns = reinterpret_cast<const uint16_t*>(this); |
| uint16_t insn = *insns; |
| int opcode = insn & 0xFF; |
| |
| switch (Format()) { |
| case k10x: // op |
| /* nothing to do; copy the AA bits out for the verifier */ |
| vA = INST_AA(insn); |
| break; |
| case k12x: // op vA, vB |
| vA = INST_A(insn); |
| vB = INST_B(insn); |
| break; |
| case k11n: // op vA, #+B |
| vA = INST_A(insn); |
| vB = (int32_t) (INST_B(insn) << 28) >> 28; // sign extend 4-bit value |
| break; |
| case k11x: // op vAA |
| vA = INST_AA(insn); |
| break; |
| case k10t: // op +AA |
| vA = (int8_t) INST_AA(insn); // sign-extend 8-bit value |
| break; |
| case k20t: // op +AAAA |
| vA = (int16_t) FETCH(1); // sign-extend 16-bit value |
| break; |
| case k21c: // op vAA, thing@BBBB |
| case k22x: // op vAA, vBBBB |
| vA = INST_AA(insn); |
| vB = FETCH(1); |
| break; |
| case k21s: // op vAA, #+BBBB |
| case k21t: // op vAA, +BBBB |
| vA = INST_AA(insn); |
| vB = (int16_t) FETCH(1); // sign-extend 16-bit value |
| break; |
| case k21h: // op vAA, #+BBBB0000[00000000] |
| vA = INST_AA(insn); |
| /* |
| * The value should be treated as right-zero-extended, but we don't |
| * actually do that here. Among other things, we don't know if it's |
| * the top bits of a 32- or 64-bit value. |
| */ |
| vB = FETCH(1); |
| break; |
| case k23x: // op vAA, vBB, vCC |
| vA = INST_AA(insn); |
| vB = FETCH(1) & 0xff; |
| vC = FETCH(1) >> 8; |
| break; |
| case k22b: // op vAA, vBB, #+CC |
| vA = INST_AA(insn); |
| vB = FETCH(1) & 0xff; |
| vC = (int8_t) (FETCH(1) >> 8); // sign-extend 8-bit value |
| break; |
| case k22s: // op vA, vB, #+CCCC |
| case k22t: // op vA, vB, +CCCC |
| vA = INST_A(insn); |
| vB = INST_B(insn); |
| vC = (int16_t) FETCH(1); // sign-extend 16-bit value |
| break; |
| case k22c: // op vA, vB, thing@CCCC |
| vA = INST_A(insn); |
| vB = INST_B(insn); |
| vC = FETCH(1); |
| break; |
| case k30t: // op +AAAAAAAA |
| vA = FETCH_u4(1); // signed 32-bit value |
| break; |
| case k31t: // op vAA, +BBBBBBBB |
| case k31c: // op vAA, string@BBBBBBBB |
| vA = INST_AA(insn); |
| vB = FETCH_u4(1); // 32-bit value |
| break; |
| case k32x: // op vAAAA, vBBBB |
| vA = FETCH(1); |
| vB = FETCH(2); |
| break; |
| case k31i: // op vAA, #+BBBBBBBB |
| vA = INST_AA(insn); |
| vB = FETCH_u4(1); // signed 32-bit value |
| break; |
| case k35c: // op {vC, vD, vE, vF, vG}, thing@BBBB |
| { |
| /* |
| * Note that the fields mentioned in the spec don't appear in |
| * their "usual" positions here compared to most formats. This |
| * was done so that the field names for the argument count and |
| * reference index match between this format and the corresponding |
| * range formats (3rc and friends). |
| * |
| * Bottom line: The argument count is always in vA, and the |
| * method constant (or equivalent) is always in vB. |
| */ |
| uint16_t regList; |
| int count; |
| |
| vA = INST_B(insn); // This is labeled A in the spec. |
| vB = FETCH(1); |
| regList = FETCH(2); |
| |
| count = vA; |
| |
| /* |
| * Copy the argument registers into the arg[] array, and |
| * also copy the first argument (if any) into vC. (The |
| * DecodedInstruction structure doesn't have separate |
| * fields for {vD, vE, vF, vG}, so there's no need to make |
| * copies of those.) Note that cases 5..2 fall through. |
| */ |
| switch (count) { |
| case 5: arg[4] = INST_A(insn); |
| case 4: arg[3] = (regList >> 12) & 0x0f; |
| case 3: arg[2] = (regList >> 8) & 0x0f; |
| case 2: arg[1] = (regList >> 4) & 0x0f; |
| case 1: vC = arg[0] = regList & 0x0f; break; |
| case 0: break; // Valid, but no need to do anything. |
| default: |
| LOG(ERROR) << "Invalid arg count in 35c (" << count << ")"; |
| return; |
| } |
| } |
| break; |
| case k3rc: // op {vCCCC .. v(CCCC+AA-1)}, meth@BBBB |
| vA = INST_AA(insn); |
| vB = FETCH(1); |
| vC = FETCH(2); |
| break; |
| case k51l: // op vAA, #+BBBBBBBBBBBBBBBB |
| vA = INST_AA(insn); |
| vB_wide = FETCH_u4(1) | ((uint64_t) FETCH_u4(3) << 32); |
| break; |
| default: |
| LOG(ERROR) << "Can't decode unexpected format " << (int) Format() << " (op=" << opcode << ")"; |
| return; |
| } |
| } |
| |
| size_t Instruction::Size() const { |
| const uint16_t* insns = reinterpret_cast<const uint16_t*>(this); |
| if (*insns == kPackedSwitchSignature) { |
| return (4 + insns[1] * 2); |
| } else if (*insns == kSparseSwitchSignature) { |
| return (2 + insns[1] * 4); |
| } else if (*insns == kArrayDataSignature) { |
| uint16_t element_size = insns[1]; |
| uint32_t length = insns[2] | (((uint32_t)insns[3]) << 16); |
| // The plus 1 is to round up for odd size and width. |
| return (4 + (element_size * length + 1) / 2); |
| } else { |
| switch (Format()) { |
| case k10x: |
| case k12x: |
| case k11n: |
| case k11x: |
| case k10t: |
| return 1; |
| case k20t: |
| case k22x: |
| case k21t: |
| case k21s: |
| case k21h: |
| case k21c: |
| case k23x: |
| case k22b: |
| case k22t: |
| case k22s: |
| case k22c: |
| return 2; |
| case k32x: |
| case k30t: |
| case k31t: |
| case k31i: |
| case k31c: |
| case k35c: |
| case k3rc: |
| return 3; |
| case k51l: |
| return 5; |
| default: |
| LOG(FATAL) << "Unreachable"; |
| } |
| } |
| return 0; |
| } |
| |
| Instruction::Code Instruction::Opcode() const { |
| const uint16_t* insns = reinterpret_cast<const uint16_t*>(this); |
| int opcode = *insns & 0xFF; |
| return static_cast<Code>(opcode); |
| } |
| |
| const Instruction* Instruction::Next() const { |
| size_t current_size = Size() * sizeof(uint16_t); |
| const uint8_t* ptr = reinterpret_cast<const uint8_t*>(this); |
| return reinterpret_cast<const Instruction*>(ptr + current_size); |
| } |
| |
| } // namespace art |