package cangjie_lua.codegen
// Lua 5.5 二进制块头部常量
let LUA_SIGNATURE: Array<UInt8> = [0x1b, 0x4c, 0x75, 0x61] // "\x1bLua"
let LUAC_VERSION: UInt8 = 0x55 // Lua 5.5
let LUAC_FORMAT: UInt8 = 0x00 // 官方格式
let LUAC_DATA: Array<UInt8> = [0x19, 0x93, 0x0d, 0x0a, 0x1a, 0x0a] // 校验数据
let LUAC_INT: Int32 = -0x5678 // 整数格式校验值
let LUAC_INST: UInt32 = 0x12345678 // 指令格式校验值（字节序检测）
let LUAC_INT64: Int64 = -0x5678 // 64 位整数校验值
let LUAC_NUM: Float64 = -370.5 // 浮点数格式校验值
// Lua 5.5 指令格式位域常量
// Lua 指令为 32 位定长，常见编码形式：
// iABC : [opcode:7][A:8][k:1][B:8][C:8]
// iABx : [opcode:7][A:8][Bx:17]
// iAsBx: [opcode:7][A:8][sBx:17 signed]
// isJ : [opcode:7][sJ:25 signed]
let A_SHIFT: UInt32 = 7 // A 字段起始位 = OP_BITS
let K_SHIFT: UInt32 = 15 // k 标志起始位 = OP_BITS + A_BITS
let B_SHIFT: UInt32 = 16 // B 字段起始位 = OP_BITS + A_BITS + K_BITS
let C_SHIFT: UInt32 = 24 // C 字段起始位 = OP_BITS + A_BITS + K_BITS + B_BITS
let BX_SHIFT: UInt32 = 15 // Bx 字段起始位 = OP_BITS + A_BITS
let SJ_SHIFT: UInt32 = 7 // sJ 字段起始位 = OP_BITS
let A_MASK: UInt32 = 0xFF // A 字段掩码 (8 bits)
let B_MASK: UInt32 = 0xFF // B 字段掩码 (8 bits)
let C_MASK: UInt32 = 0xFF // C 字段掩码 (8 bits)
let K_MASK: UInt32 = 0x1 // k 标志掩码 (1 bit)
let BX_MASK: UInt32 = 0x1FFFF // Bx 字段掩码 (17 bits)
let SJ_MASK: UInt32 = 0x1FFFFFF // sJ 字段掩码 (25 bits)
let SBX_OFFSET: Int32 = 65535 // sBx 偏移量 = 2^16 - 1 (将有符号值映射到无符号)
let SJ_OFFSET: Int32 = 16777215 // sJ 偏移量 = 2^24 - 1
let SB_OFFSET: Int32 = 127 // sB 偏移量 = 2^7 - 1 (EQI 指令的 sB 字段)
// OpCodes：Lua 5.5 虚拟机操作码枚举（共 85 个）
public enum OpCodes {
| MOVE
| LOADI
| LOADF
| LOADK
| LOADKX
| LOADFALSE
| LFALSESKIP
| LOADTRUE
| LOADNIL
| GETUPVAL
| SETUPVAL
| GETTABUP
| GETTABLE
| GETI
| GETFIELD
| SETTABUP
| SETTABLE
| SETI
| SETFIELD
| NEWTABLE
| SELF
| ADDI
| ADDK
| SUBK
| MULK
| MODK
| POWK
| DIVK
| IDIVK
| BANDK
| BORK
| BXORK
| SHLI
| SHRI
| ADD
| SUB
| MUL
| MOD
| POW
| DIV
| IDIV
| BAND
| BOR
| BXOR
| SHL
| SHR
| MMBIN
| MMBINI
| MMBINK
| UNM
| BNOT
| NOT
| LEN
| CONCAT
| CLOSE
| TBC
| JMP
| EQ
| LT
| LE
| EQK
| EQI
| LTI
| LEI
| GTI
| GEI
| TEST
| TESTSET
| CALL
| TAILCALL
| RETURN
| RETURN0
| RETURN1
| FORLOOP
| FORPREP
| TFORPREP
| TFORCALL
| TFORLOOP
| SETLIST
| CLOSURE
| VARARG
| GETVARG
| ERRNNIL
| VARARGPREP
| EXTRAARG
}
/// 将 OpCodes 枚举映射为对应的数值编号
public func opcodeValue(op: OpCodes): UInt32 {
match (op) {
case OpCodes.MOVE => 0
case OpCodes.LOADI => 1
case OpCodes.LOADF => 2
case OpCodes.LOADK => 3
case OpCodes.LOADKX => 4
case OpCodes.LOADFALSE => 5
case OpCodes.LFALSESKIP => 6
case OpCodes.LOADTRUE => 7
case OpCodes.LOADNIL => 8
case OpCodes.GETUPVAL => 9
case OpCodes.SETUPVAL => 10
case OpCodes.GETTABUP => 11
case OpCodes.GETTABLE => 12
case OpCodes.GETI => 13
case OpCodes.GETFIELD => 14
case OpCodes.SETTABUP => 15
case OpCodes.SETTABLE => 16
case OpCodes.SETI => 17
case OpCodes.SETFIELD => 18
case OpCodes.NEWTABLE => 19
case OpCodes.SELF => 20
case OpCodes.ADDI => 21
case OpCodes.ADDK => 22
case OpCodes.SUBK => 23
case OpCodes.MULK => 24
case OpCodes.MODK => 25
case OpCodes.POWK => 26
case OpCodes.DIVK => 27
case OpCodes.IDIVK => 28
case OpCodes.BANDK => 29
case OpCodes.BORK => 30
case OpCodes.BXORK => 31
case OpCodes.SHLI => 32
case OpCodes.SHRI => 33
case OpCodes.ADD => 34
case OpCodes.SUB => 35
case OpCodes.MUL => 36
case OpCodes.MOD => 37
case OpCodes.POW => 38
case OpCodes.DIV => 39
case OpCodes.IDIV => 40
case OpCodes.BAND => 41
case OpCodes.BOR => 42
case OpCodes.BXOR => 43
case OpCodes.SHL => 44
case OpCodes.SHR => 45
case OpCodes.MMBIN => 46
case OpCodes.MMBINI => 47
case OpCodes.MMBINK => 48
case OpCodes.UNM => 49
case OpCodes.BNOT => 50
case OpCodes.NOT => 51
case OpCodes.LEN => 52
case OpCodes.CONCAT => 53
case OpCodes.CLOSE => 54
case OpCodes.TBC => 55
case OpCodes.JMP => 56
case OpCodes.EQ => 57
case OpCodes.LT => 58
case OpCodes.LE => 59
case OpCodes.EQK => 60
case OpCodes.EQI => 61
case OpCodes.LTI => 62
case OpCodes.LEI => 63
case OpCodes.GTI => 64
case OpCodes.GEI => 65
case OpCodes.TEST => 66
case OpCodes.TESTSET => 67
case OpCodes.CALL => 68
case OpCodes.TAILCALL => 69
case OpCodes.RETURN => 70
case OpCodes.RETURN0 => 71
case OpCodes.RETURN1 => 72
case OpCodes.FORLOOP => 73
case OpCodes.FORPREP => 74
case OpCodes.TFORPREP => 75
case OpCodes.TFORCALL => 76
case OpCodes.TFORLOOP => 77
case OpCodes.SETLIST => 78
case OpCodes.CLOSURE => 79
case OpCodes.VARARG => 80
case OpCodes.GETVARG => 81
case OpCodes.ERRNNIL => 82
case OpCodes.VARARGPREP => 83
case OpCodes.EXTRAARG => 84
}
}
// 指令编码函数：将操作码与操作数打包为 32 位指令
/// 编码 iABC 格式指令：op | A | B | C
public func encodeABC(op: OpCodes, a: UInt32, b: UInt32, c: UInt32): UInt32 {
return opcodeValue(op) | ((a & A_MASK) << A_SHIFT) | ((b & B_MASK) << B_SHIFT) | ((c & C_MASK) << C_SHIFT)
}
/// 编码 iABx 格式指令：op | A | Bx（无符号）
public func encodeABx(op: OpCodes, a: UInt32, bx: UInt32): UInt32 {
return opcodeValue(op) | ((a & A_MASK) << A_SHIFT) | ((bx & BX_MASK) << BX_SHIFT)
}
/// 编码 iAsBx 格式指令：op | A | sBx（有符号，加偏移量转无符号）
public func encodeAsBx(op: OpCodes, a: UInt32, sbx: Int32): UInt32 {
let unsignedSbx = UInt32(sbx + SBX_OFFSET)
return opcodeValue(op) | ((a & A_MASK) << A_SHIFT) | ((unsignedSbx & BX_MASK) << BX_SHIFT)
}
/// 编码 isJ 格式指令：op | sJ（有符号跳转偏移量）
public func encodeIsJ(op: OpCodes, sj: Int32): UInt32 {
let unsignedSj = UInt32(sj + SJ_OFFSET)
return opcodeValue(op) | ((unsignedSj & SJ_MASK) << SJ_SHIFT)
}
/// 编码 iABC 格式指令（带 k 标志位）：op | A | k | B | C
public func encodeABCK(op: OpCodes, a: UInt32, b: UInt32, c: UInt32, k: UInt32): UInt32 {
return opcodeValue(op) | ((a & A_MASK) << A_SHIFT) | ((b & B_MASK) << B_SHIFT) | (c << C_SHIFT) | ((k & K_MASK) << K_SHIFT)
}
/// 编码 EQI 指令：EQI A sB k —— 比较寄存器 A 与立即数 sB
public func encodeEQI(a: UInt32, sB: Int32, k: UInt32): UInt32 {
let offsetB = UInt32(sB + SB_OFFSET)
return opcodeValue(OpCodes.EQI) | ((a & A_MASK) << A_SHIFT) | ((offsetB & B_MASK) << B_SHIFT) | ((k & K_MASK) << K_SHIFT)
}
