PPCDisassembler.c

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//===------ PPCDisassembler.cpp - Disassembler for PowerPC ------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
 
/* Capstone Disassembly Engine */
/* By Nguyen Anh Quynh <aquynh@gmail.com>, 2013-2015 */
 
#ifdef CAPSTONE_HAS_POWERPC
 
#include <stdio.h>  // DEBUG
#include <stdlib.h>
#include <string.h>
 
#include "../../cs_priv.h"
#include "../../utils.h"
 
#include "PPCDisassembler.h"
 
#include "../../MCInst.h"
#include "../../MCInstrDesc.h"
#include "../../MCFixedLenDisassembler.h"
#include "../../MCRegisterInfo.h"
#include "../../MCDisassembler.h"
#include "../../MathExtras.h"
 
#define GET_REGINFO_ENUM
#include "PPCGenRegisterInfo.inc"
 
 
// FIXME: These can be generated by TableGen from the existing register
// encoding values!
 
static const unsigned CRRegs[] = {
    PPC_CR0, PPC_CR1, PPC_CR2, PPC_CR3,
    PPC_CR4, PPC_CR5, PPC_CR6, PPC_CR7
};
 
static const unsigned CRBITRegs[] = {
    PPC_CR0LT, PPC_CR0GT, PPC_CR0EQ, PPC_CR0UN,
    PPC_CR1LT, PPC_CR1GT, PPC_CR1EQ, PPC_CR1UN,
    PPC_CR2LT, PPC_CR2GT, PPC_CR2EQ, PPC_CR2UN,
    PPC_CR3LT, PPC_CR3GT, PPC_CR3EQ, PPC_CR3UN,
    PPC_CR4LT, PPC_CR4GT, PPC_CR4EQ, PPC_CR4UN,
    PPC_CR5LT, PPC_CR5GT, PPC_CR5EQ, PPC_CR5UN,
    PPC_CR6LT, PPC_CR6GT, PPC_CR6EQ, PPC_CR6UN,
    PPC_CR7LT, PPC_CR7GT, PPC_CR7EQ, PPC_CR7UN
};
 
static const unsigned FRegs[] = {
    PPC_F0, PPC_F1, PPC_F2, PPC_F3,
    PPC_F4, PPC_F5, PPC_F6, PPC_F7,
    PPC_F8, PPC_F9, PPC_F10, PPC_F11,
    PPC_F12, PPC_F13, PPC_F14, PPC_F15,
    PPC_F16, PPC_F17, PPC_F18, PPC_F19,
    PPC_F20, PPC_F21, PPC_F22, PPC_F23,
    PPC_F24, PPC_F25, PPC_F26, PPC_F27,
    PPC_F28, PPC_F29, PPC_F30, PPC_F31
};
 
static const unsigned VRegs[] = {
    PPC_V0, PPC_V1, PPC_V2, PPC_V3,
    PPC_V4, PPC_V5, PPC_V6, PPC_V7,
    PPC_V8, PPC_V9, PPC_V10, PPC_V11,
    PPC_V12, PPC_V13, PPC_V14, PPC_V15,
    PPC_V16, PPC_V17, PPC_V18, PPC_V19,
    PPC_V20, PPC_V21, PPC_V22, PPC_V23,
    PPC_V24, PPC_V25, PPC_V26, PPC_V27,
    PPC_V28, PPC_V29, PPC_V30, PPC_V31
};
 
static const unsigned VSRegs[] = {
    PPC_VSL0, PPC_VSL1, PPC_VSL2, PPC_VSL3,
    PPC_VSL4, PPC_VSL5, PPC_VSL6, PPC_VSL7,
    PPC_VSL8, PPC_VSL9, PPC_VSL10, PPC_VSL11,
    PPC_VSL12, PPC_VSL13, PPC_VSL14, PPC_VSL15,
    PPC_VSL16, PPC_VSL17, PPC_VSL18, PPC_VSL19,
    PPC_VSL20, PPC_VSL21, PPC_VSL22, PPC_VSL23,
    PPC_VSL24, PPC_VSL25, PPC_VSL26, PPC_VSL27,
    PPC_VSL28, PPC_VSL29, PPC_VSL30, PPC_VSL31,
 
    PPC_VSH0, PPC_VSH1, PPC_VSH2, PPC_VSH3,
    PPC_VSH4, PPC_VSH5, PPC_VSH6, PPC_VSH7,
    PPC_VSH8, PPC_VSH9, PPC_VSH10, PPC_VSH11,
    PPC_VSH12, PPC_VSH13, PPC_VSH14, PPC_VSH15,
    PPC_VSH16, PPC_VSH17, PPC_VSH18, PPC_VSH19,
    PPC_VSH20, PPC_VSH21, PPC_VSH22, PPC_VSH23,
    PPC_VSH24, PPC_VSH25, PPC_VSH26, PPC_VSH27,
    PPC_VSH28, PPC_VSH29, PPC_VSH30, PPC_VSH31
};
 
static const unsigned VSFRegs[] = {
    PPC_F0, PPC_F1, PPC_F2, PPC_F3,
    PPC_F4, PPC_F5, PPC_F6, PPC_F7,
    PPC_F8, PPC_F9, PPC_F10, PPC_F11,
    PPC_F12, PPC_F13, PPC_F14, PPC_F15,
    PPC_F16, PPC_F17, PPC_F18, PPC_F19,
    PPC_F20, PPC_F21, PPC_F22, PPC_F23,
    PPC_F24, PPC_F25, PPC_F26, PPC_F27,
    PPC_F28, PPC_F29, PPC_F30, PPC_F31,
 
    PPC_VF0, PPC_VF1, PPC_VF2, PPC_VF3,
    PPC_VF4, PPC_VF5, PPC_VF6, PPC_VF7,
    PPC_VF8, PPC_VF9, PPC_VF10, PPC_VF11,
    PPC_VF12, PPC_VF13, PPC_VF14, PPC_VF15,
    PPC_VF16, PPC_VF17, PPC_VF18, PPC_VF19,
    PPC_VF20, PPC_VF21, PPC_VF22, PPC_VF23,
    PPC_VF24, PPC_VF25, PPC_VF26, PPC_VF27,
    PPC_VF28, PPC_VF29, PPC_VF30, PPC_VF31
};
 
static const unsigned GPRegs[] = {
    PPC_R0, PPC_R1, PPC_R2, PPC_R3,
    PPC_R4, PPC_R5, PPC_R6, PPC_R7,
    PPC_R8, PPC_R9, PPC_R10, PPC_R11,
    PPC_R12, PPC_R13, PPC_R14, PPC_R15,
    PPC_R16, PPC_R17, PPC_R18, PPC_R19,
    PPC_R20, PPC_R21, PPC_R22, PPC_R23,
    PPC_R24, PPC_R25, PPC_R26, PPC_R27,
    PPC_R28, PPC_R29, PPC_R30, PPC_R31
};
 
static const unsigned GP0Regs[] = {
    PPC_ZERO, PPC_R1, PPC_R2, PPC_R3,
    PPC_R4, PPC_R5, PPC_R6, PPC_R7,
    PPC_R8, PPC_R9, PPC_R10, PPC_R11,
    PPC_R12, PPC_R13, PPC_R14, PPC_R15,
    PPC_R16, PPC_R17, PPC_R18, PPC_R19,
    PPC_R20, PPC_R21, PPC_R22, PPC_R23,
    PPC_R24, PPC_R25, PPC_R26, PPC_R27,
    PPC_R28, PPC_R29, PPC_R30, PPC_R31
};
 
static const unsigned G8Regs[] = {
    PPC_X0, PPC_X1, PPC_X2, PPC_X3,
    PPC_X4, PPC_X5, PPC_X6, PPC_X7,
    PPC_X8, PPC_X9, PPC_X10, PPC_X11,
    PPC_X12, PPC_X13, PPC_X14, PPC_X15,
    PPC_X16, PPC_X17, PPC_X18, PPC_X19,
    PPC_X20, PPC_X21, PPC_X22, PPC_X23,
    PPC_X24, PPC_X25, PPC_X26, PPC_X27,
    PPC_X28, PPC_X29, PPC_X30, PPC_X31
};
 
static const unsigned QFRegs[] = {
    PPC_QF0, PPC_QF1, PPC_QF2, PPC_QF3,
    PPC_QF4, PPC_QF5, PPC_QF6, PPC_QF7,
    PPC_QF8, PPC_QF9, PPC_QF10, PPC_QF11,
    PPC_QF12, PPC_QF13, PPC_QF14, PPC_QF15,
    PPC_QF16, PPC_QF17, PPC_QF18, PPC_QF19,
    PPC_QF20, PPC_QF21, PPC_QF22, PPC_QF23,
    PPC_QF24, PPC_QF25, PPC_QF26, PPC_QF27,
    PPC_QF28, PPC_QF29, PPC_QF30, PPC_QF31
};
 
static uint64_t getFeatureBits(int feature)
{
    // enable all features
    return (uint64_t)-1;
}
 
static DecodeStatus decodeRegisterClass(MCInst *Inst, uint64_t RegNo,
        const unsigned *Regs)
{
    // assert(RegNo < N && "Invalid register number");
    MCOperand_CreateReg0(Inst, Regs[RegNo]);
    return MCDisassembler_Success;
}
 
static DecodeStatus DecodeCRRCRegisterClass(MCInst *Inst, uint64_t RegNo,
        uint64_t Address,
        const void *Decoder)
{
    return decodeRegisterClass(Inst, RegNo, CRRegs);
}
 
static DecodeStatus DecodeCRBITRCRegisterClass(MCInst *Inst, uint64_t RegNo,
        uint64_t Address,
        const void *Decoder)
{
    return decodeRegisterClass(Inst, RegNo, CRBITRegs);
}
 
static DecodeStatus DecodeF4RCRegisterClass(MCInst *Inst, uint64_t RegNo,
        uint64_t Address,
        const void *Decoder)
{
    return decodeRegisterClass(Inst, RegNo, FRegs);
}
 
static DecodeStatus DecodeF8RCRegisterClass(MCInst *Inst, uint64_t RegNo,
        uint64_t Address,
        const void *Decoder)
{
    return decodeRegisterClass(Inst, RegNo, FRegs);
}
 
static DecodeStatus DecodeVRRCRegisterClass(MCInst *Inst, uint64_t RegNo,
        uint64_t Address,
        const void *Decoder)
{
    return decodeRegisterClass(Inst, RegNo, VRegs);
}
 
static DecodeStatus DecodeVSRCRegisterClass(MCInst *Inst, uint64_t RegNo,
        uint64_t Address,
        const void *Decoder)
{
    return decodeRegisterClass(Inst, RegNo, VSRegs);
}
 
static DecodeStatus DecodeVSFRCRegisterClass(MCInst *Inst, uint64_t RegNo,
        uint64_t Address,
        const void *Decoder)
{
    return decodeRegisterClass(Inst, RegNo, VSFRegs);
}
 
static DecodeStatus DecodeGPRCRegisterClass(MCInst *Inst, uint64_t RegNo,
        uint64_t Address,
        const void *Decoder)
{
    return decodeRegisterClass(Inst, RegNo, GPRegs);
}
 
static DecodeStatus DecodeGPRC_NOR0RegisterClass(MCInst *Inst, uint64_t RegNo,
        uint64_t Address,
        const void *Decoder)
{
    return decodeRegisterClass(Inst, RegNo, GP0Regs);
}
 
static DecodeStatus DecodeG8RCRegisterClass(MCInst *Inst, uint64_t RegNo,
        uint64_t Address,
        const void *Decoder)
{
    return decodeRegisterClass(Inst, RegNo, G8Regs);
}
 
#define DecodePointerLikeRegClass0 DecodeGPRCRegisterClass
#define DecodePointerLikeRegClass1 DecodeGPRC_NOR0RegisterClass
 
static DecodeStatus DecodeQFRCRegisterClass(MCInst *Inst, uint64_t RegNo,
        uint64_t Address,
        const void *Decoder)
{
    return decodeRegisterClass(Inst, RegNo, QFRegs);
}
 
#define DecodeQSRCRegisterClass DecodeQFRCRegisterClass
#define DecodeQBRCRegisterClass DecodeQFRCRegisterClass
 
static DecodeStatus decodeUImmOperand(MCInst *Inst, uint64_t Imm,
        int64_t Address, const void *Decoder, unsigned N)
{
    //assert(isUInt<N>(Imm) && "Invalid immediate");
    MCOperand_CreateImm0(Inst, Imm);
    return MCDisassembler_Success;
}
 
static DecodeStatus decodeSImmOperand(MCInst *Inst, uint64_t Imm,
        int64_t Address, const void *Decoder, unsigned N)
{
    // assert(isUInt<N>(Imm) && "Invalid immediate");
    MCOperand_CreateImm0(Inst, SignExtend64(Imm, N));
    return MCDisassembler_Success;
}
 
 
#define GET_INSTRINFO_ENUM
#include "PPCGenInstrInfo.inc"
 
static DecodeStatus decodeMemRIOperands(MCInst *Inst, uint64_t Imm,
        int64_t Address, const void *Decoder)
{
    // Decode the memri field (imm, reg), which has the low 16-bits as the
    // displacement and the next 5 bits as the register #.
 
    uint64_t Base = Imm >> 16;
    uint64_t Disp = Imm & 0xFFFF;
 
    // assert(Base < 32 && "Invalid base register");
    if (Base >= 32)
        return MCDisassembler_Fail;
 
    switch (MCInst_getOpcode(Inst)) {
        default: break;
        case PPC_LBZU:
        case PPC_LHAU:
        case PPC_LHZU:
        case PPC_LWZU:
        case PPC_LFSU:
        case PPC_LFDU:
                 // Add the tied output operand.
                 MCOperand_CreateReg0(Inst, GP0Regs[Base]);
                 break;
        case PPC_STBU:
        case PPC_STHU:
        case PPC_STWU:
        case PPC_STFSU:
        case PPC_STFDU:
                 MCInst_insert0(Inst, 0, MCOperand_CreateReg1(Inst, GP0Regs[Base]));
                 break;
    }
 
    MCOperand_CreateImm0(Inst, SignExtend64(Disp, 16));
    MCOperand_CreateReg0(Inst, GP0Regs[Base]);
    return MCDisassembler_Success;
}
 
static DecodeStatus decodeMemRIXOperands(MCInst *Inst, uint64_t Imm,
        int64_t Address, const void *Decoder)
{
    // Decode the memrix field (imm, reg), which has the low 14-bits as the
    // displacement and the next 5 bits as the register #.
 
    uint64_t Base = Imm >> 14;
    uint64_t Disp = Imm & 0x3FFF;
 
    // assert(Base < 32 && "Invalid base register");
 
    if (MCInst_getOpcode(Inst) == PPC_LDU)
        // Add the tied output operand.
        MCOperand_CreateReg0(Inst, GP0Regs[Base]);
    else if (MCInst_getOpcode(Inst) == PPC_STDU)
        MCInst_insert0(Inst, 0, MCOperand_CreateReg1(Inst, GP0Regs[Base]));
 
    MCOperand_CreateImm0(Inst, SignExtend64(Disp << 2, 16));
    MCOperand_CreateReg0(Inst, GP0Regs[Base]);
    return MCDisassembler_Success;
}
 
static DecodeStatus decodeCRBitMOperand(MCInst *Inst, uint64_t Imm,
        int64_t Address, const void *Decoder)
{
    // The cr bit encoding is 0x80 >> cr_reg_num.
 
    unsigned Zeros = CountTrailingZeros_64(Imm);
    // assert(Zeros < 8 && "Invalid CR bit value");
    if (Zeros >=8)
        return MCDisassembler_Fail;
 
    MCOperand_CreateReg0(Inst, CRRegs[7 - Zeros]);
    return MCDisassembler_Success;
}
 
#include "PPCGenDisassemblerTables.inc"
 
static DecodeStatus getInstruction(MCInst *MI,
        const uint8_t *code, size_t code_len,
        uint16_t *Size,
        uint64_t Address, MCRegisterInfo *MRI)
{
    uint32_t insn;
    DecodeStatus result;
    // Get the four bytes of the instruction.
    if (code_len < 4) {
        // not enough data
        *Size = 0;
        return MCDisassembler_Fail;
    }
 
    // The instruction is big-endian encoded.
    if (MODE_IS_BIG_ENDIAN(MI->csh->mode))
        insn = ((uint32_t) code[0] << 24) | (code[1] << 16) |
            (code[2] <<  8) | (code[3] <<  0);
    else
        insn = ((uint32_t) code[3] << 24) | (code[2] << 16) |
            (code[1] <<  8) | (code[0] <<  0);
 
    if (MI->flat_insn->detail) {
        memset(MI->flat_insn->detail, 0, offsetof(cs_detail, ppc)+sizeof(cs_ppc));
    }
 
    if (MI->csh->mode & CS_MODE_QPX) {
        result = decodeInstruction_4(DecoderTableQPX32, MI, insn, Address, 4);
        if (result != MCDisassembler_Fail) {
            *Size = 4;
            return result;
        }
 
        MCInst_clear(MI);
    }
 
    result = decodeInstruction_4(DecoderTable32, MI, insn, Address, 4);
    if (result != MCDisassembler_Fail) {
        *Size = 4;
        return result;
    }
 
    // report error
    MCInst_clear(MI);
    *Size = 0;
    return MCDisassembler_Fail;
}
 
bool PPC_getInstruction(csh ud, const uint8_t *code, size_t code_len,
        MCInst *instr, uint16_t *size, uint64_t address, void *info)
{
    DecodeStatus status = getInstruction(instr,
            code, code_len,
            size,
            address, (MCRegisterInfo *)info);
 
    return status == MCDisassembler_Success;
}
 
#define GET_REGINFO_MC_DESC
#include "PPCGenRegisterInfo.inc"
void PPC_init(MCRegisterInfo *MRI)
{
    /*
       InitMCRegisterInfo(PPCRegDesc, 310, RA, PC,
       PPCMCRegisterClasses, 23,
       PPCRegUnitRoots,
       138,
       PPCRegDiffLists,
       PPCLaneMaskLists,
       PPCRegStrings,
       PPCRegClassStrings,
       PPCSubRegIdxLists,
       8,
       PPCSubRegIdxRanges,
       PPCRegEncodingTable);
     */
 
 
    MCRegisterInfo_InitMCRegisterInfo(MRI, PPCRegDesc, 310,
            0, 0,
            PPCMCRegisterClasses, 23,
            0, 0,
            PPCRegDiffLists,
            0,
            PPCSubRegIdxLists, 8,
            0);
}
 
#endif