forked from OSchip/llvm-project
2322 lines
84 KiB
C++
2322 lines
84 KiB
C++
//===-- EmulateInstructionARM.cpp -------------------------------*- C++ -*-===//
|
||
//
|
||
// The LLVM Compiler Infrastructure
|
||
//
|
||
// This file is distributed under the University of Illinois Open Source
|
||
// License. See LICENSE.TXT for details.
|
||
//
|
||
//===----------------------------------------------------------------------===//
|
||
|
||
#include "EmulateInstructionARM.h"
|
||
#include "lldb/Core/ConstString.h"
|
||
|
||
#include "Plugins/Process/Utility/ARMDefines.h"
|
||
#include "Plugins/Process/Utility/ARMUtils.h"
|
||
#include "Utility/ARM_DWARF_Registers.h"
|
||
|
||
#include "llvm/Support/MathExtras.h" // for SignExtend32 template function
|
||
// and CountTrailingZeros_32 function
|
||
|
||
using namespace lldb;
|
||
using namespace lldb_private;
|
||
|
||
static inline uint32_t Align(uint32_t val, uint32_t alignment)
|
||
{
|
||
return alignment * (val / alignment);
|
||
}
|
||
|
||
// A8.6.50
|
||
// Valid return values are {1, 2, 3, 4}, with 0 signifying an error condition.
|
||
static unsigned short CountITSize(unsigned ITMask) {
|
||
// First count the trailing zeros of the IT mask.
|
||
unsigned TZ = llvm::CountTrailingZeros_32(ITMask);
|
||
if (TZ > 3)
|
||
{
|
||
printf("Encoding error: IT Mask '0000'\n");
|
||
return 0;
|
||
}
|
||
return (4 - TZ);
|
||
}
|
||
|
||
// Init ITState. Note that at least one bit is always 1 in mask.
|
||
bool ITSession::InitIT(unsigned short bits7_0)
|
||
{
|
||
ITCounter = CountITSize(Bits32(bits7_0, 3, 0));
|
||
if (ITCounter == 0)
|
||
return false;
|
||
|
||
// A8.6.50 IT
|
||
unsigned short FirstCond = Bits32(bits7_0, 7, 4);
|
||
if (FirstCond == 0xF)
|
||
{
|
||
printf("Encoding error: IT FirstCond '1111'\n");
|
||
return false;
|
||
}
|
||
if (FirstCond == 0xE && ITCounter != 1)
|
||
{
|
||
printf("Encoding error: IT FirstCond '1110' && Mask != '1000'\n");
|
||
return false;
|
||
}
|
||
|
||
ITState = bits7_0;
|
||
return true;
|
||
}
|
||
|
||
// Update ITState if necessary.
|
||
void ITSession::ITAdvance()
|
||
{
|
||
assert(ITCounter);
|
||
--ITCounter;
|
||
if (ITCounter == 0)
|
||
ITState = 0;
|
||
else
|
||
{
|
||
unsigned short NewITState4_0 = Bits32(ITState, 4, 0) << 1;
|
||
SetBits32(ITState, 4, 0, NewITState4_0);
|
||
}
|
||
}
|
||
|
||
// Return true if we're inside an IT Block.
|
||
bool ITSession::InITBlock()
|
||
{
|
||
return ITCounter != 0;
|
||
}
|
||
|
||
// Return true if we're the last instruction inside an IT Block.
|
||
bool ITSession::LastInITBlock()
|
||
{
|
||
return ITCounter == 1;
|
||
}
|
||
|
||
// Get condition bits for the current thumb instruction.
|
||
uint32_t ITSession::GetCond()
|
||
{
|
||
if (InITBlock())
|
||
return Bits32(ITState, 7, 4);
|
||
else
|
||
return COND_AL;
|
||
}
|
||
|
||
// ARM constants used during decoding
|
||
#define REG_RD 0
|
||
#define LDM_REGLIST 1
|
||
#define PC_REG 15
|
||
#define PC_REGLIST_BIT 0x8000
|
||
|
||
#define ARMv4 (1u << 0)
|
||
#define ARMv4T (1u << 1)
|
||
#define ARMv5T (1u << 2)
|
||
#define ARMv5TE (1u << 3)
|
||
#define ARMv5TEJ (1u << 4)
|
||
#define ARMv6 (1u << 5)
|
||
#define ARMv6K (1u << 6)
|
||
#define ARMv6T2 (1u << 7)
|
||
#define ARMv7 (1u << 8)
|
||
#define ARMv8 (1u << 9)
|
||
#define ARMvAll (0xffffffffu)
|
||
|
||
#define ARMV4T_ABOVE (ARMv4T|ARMv5T|ARMv5TE|ARMv5TEJ|ARMv6|ARMv6K|ARMv6T2|ARMv7|ARMv8)
|
||
#define ARMV5_ABOVE (ARMv5T|ARMv5TE|ARMv5TEJ|ARMv6|ARMv6K|ARMv6T2|ARMv7|ARMv8)
|
||
#define ARMV6T2_ABOVE (ARMv6T2|ARMv7|ARMv8)
|
||
|
||
void
|
||
EmulateInstructionARM::Initialize ()
|
||
{
|
||
}
|
||
|
||
void
|
||
EmulateInstructionARM::Terminate ()
|
||
{
|
||
}
|
||
|
||
// Push Multiple Registers stores multiple registers to the stack, storing to
|
||
// consecutive memory locations ending just below the address in SP, and updates
|
||
// SP to point to the start of the stored data.
|
||
bool
|
||
EmulateInstructionARM::EmulatePush (ARMEncoding encoding)
|
||
{
|
||
#if 0
|
||
// ARM pseudo code...
|
||
if (ConditionPassed())
|
||
{
|
||
EncodingSpecificOperations();
|
||
NullCheckIfThumbEE(13);
|
||
address = SP - 4*BitCount(registers);
|
||
|
||
for (i = 0 to 14)
|
||
{
|
||
if (registers<i> == ’1’)
|
||
{
|
||
if i == 13 && i != LowestSetBit(registers) // Only possible for encoding A1
|
||
MemA[address,4] = bits(32) UNKNOWN;
|
||
else
|
||
MemA[address,4] = R[i];
|
||
address = address + 4;
|
||
}
|
||
}
|
||
|
||
if (registers<15> == ’1’) // Only possible for encoding A1 or A2
|
||
MemA[address,4] = PCStoreValue();
|
||
|
||
SP = SP - 4*BitCount(registers);
|
||
}
|
||
#endif
|
||
|
||
bool success = false;
|
||
const uint32_t opcode = OpcodeAsUnsigned (&success);
|
||
if (!success)
|
||
return false;
|
||
|
||
if (ConditionPassed())
|
||
{
|
||
const uint32_t addr_byte_size = GetAddressByteSize();
|
||
const addr_t sp = ReadRegisterUnsigned (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
uint32_t registers = 0;
|
||
uint32_t Rt; // the source register
|
||
switch (encoding) {
|
||
case eEncodingT1:
|
||
registers = Bits32(opcode, 7, 0);
|
||
// The M bit represents LR.
|
||
if (Bits32(opcode, 8, 8))
|
||
registers |= (1u << 14);
|
||
// if BitCount(registers) < 1 then UNPREDICTABLE;
|
||
if (BitCount(registers) < 1)
|
||
return false;
|
||
break;
|
||
case eEncodingT2:
|
||
// Ignore bits 15 & 13.
|
||
registers = Bits32(opcode, 15, 0) & ~0xa000;
|
||
// if BitCount(registers) < 2 then UNPREDICTABLE;
|
||
if (BitCount(registers) < 2)
|
||
return false;
|
||
break;
|
||
case eEncodingT3:
|
||
Rt = Bits32(opcode, 15, 12);
|
||
// if BadReg(t) then UNPREDICTABLE;
|
||
if (BadReg(Rt))
|
||
return false;
|
||
registers = (1u << Rt);
|
||
break;
|
||
case eEncodingA1:
|
||
registers = Bits32(opcode, 15, 0);
|
||
// Instead of return false, let's handle the following case as well,
|
||
// which amounts to pushing one reg onto the full descending stacks.
|
||
// if BitCount(register_list) < 2 then SEE STMDB / STMFD;
|
||
break;
|
||
case eEncodingA2:
|
||
Rt = Bits32(opcode, 15, 12);
|
||
// if t == 13 then UNPREDICTABLE;
|
||
if (Rt == dwarf_sp)
|
||
return false;
|
||
registers = (1u << Rt);
|
||
break;
|
||
default:
|
||
return false;
|
||
}
|
||
addr_t sp_offset = addr_byte_size * BitCount (registers);
|
||
addr_t addr = sp - sp_offset;
|
||
uint32_t i;
|
||
|
||
EmulateInstruction::Context context = { EmulateInstruction::eContextPushRegisterOnStack, eRegisterKindDWARF, 0, 0 };
|
||
for (i=0; i<15; ++i)
|
||
{
|
||
if (BitIsSet (registers, i))
|
||
{
|
||
context.arg1 = dwarf_r0 + i; // arg1 in the context is the DWARF register number
|
||
context.arg2 = addr - sp; // arg2 in the context is the stack pointer offset
|
||
uint32_t reg_value = ReadRegisterUnsigned(eRegisterKindDWARF, context.arg1, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
if (!WriteMemoryUnsigned (context, addr, reg_value, addr_byte_size))
|
||
return false;
|
||
addr += addr_byte_size;
|
||
}
|
||
}
|
||
|
||
if (BitIsSet (registers, 15))
|
||
{
|
||
context.arg1 = dwarf_pc; // arg1 in the context is the DWARF register number
|
||
context.arg2 = addr - sp; // arg2 in the context is the stack pointer offset
|
||
const uint32_t pc = ReadRegisterUnsigned(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
if (!WriteMemoryUnsigned (context, addr, pc + 8, addr_byte_size))
|
||
return false;
|
||
}
|
||
|
||
context.type = EmulateInstruction::eContextAdjustStackPointer;
|
||
context.arg0 = eRegisterKindGeneric;
|
||
context.arg1 = LLDB_REGNUM_GENERIC_SP;
|
||
context.arg2 = -sp_offset;
|
||
|
||
if (!WriteRegisterUnsigned (context, eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP, sp - sp_offset))
|
||
return false;
|
||
}
|
||
return true;
|
||
}
|
||
|
||
// Pop Multiple Registers loads multiple registers from the stack, loading from
|
||
// consecutive memory locations staring at the address in SP, and updates
|
||
// SP to point just above the loaded data.
|
||
bool
|
||
EmulateInstructionARM::EmulatePop (ARMEncoding encoding)
|
||
{
|
||
#if 0
|
||
// ARM pseudo code...
|
||
if (ConditionPassed())
|
||
{
|
||
EncodingSpecificOperations(); NullCheckIfThumbEE(13);
|
||
address = SP;
|
||
for i = 0 to 14
|
||
if registers<i> == ‘1’ then
|
||
R[i} = if UnalignedAllowed then MemU[address,4] else MemA[address,4]; address = address + 4;
|
||
if registers<15> == ‘1’ then
|
||
if UnalignedAllowed then
|
||
LoadWritePC(MemU[address,4]);
|
||
else
|
||
LoadWritePC(MemA[address,4]);
|
||
if registers<13> == ‘0’ then SP = SP + 4*BitCount(registers);
|
||
if registers<13> == ‘1’ then SP = bits(32) UNKNOWN;
|
||
}
|
||
#endif
|
||
|
||
bool success = false;
|
||
const uint32_t opcode = OpcodeAsUnsigned (&success);
|
||
if (!success)
|
||
return false;
|
||
|
||
if (ConditionPassed())
|
||
{
|
||
const uint32_t addr_byte_size = GetAddressByteSize();
|
||
const addr_t sp = ReadRegisterUnsigned (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
uint32_t registers = 0;
|
||
uint32_t Rt; // the destination register
|
||
switch (encoding) {
|
||
case eEncodingT1:
|
||
registers = Bits32(opcode, 7, 0);
|
||
// The P bit represents PC.
|
||
if (Bits32(opcode, 8, 8))
|
||
registers |= (1u << 15);
|
||
// if BitCount(registers) < 1 then UNPREDICTABLE;
|
||
if (BitCount(registers) < 1)
|
||
return false;
|
||
break;
|
||
case eEncodingT2:
|
||
// Ignore bit 13.
|
||
registers = Bits32(opcode, 15, 0) & ~0x2000;
|
||
// if BitCount(registers) < 2 || (P == '1' && M == '1') then UNPREDICTABLE;
|
||
if (BitCount(registers) < 2 || (Bits32(opcode, 15, 15) && Bits32(opcode, 14, 14)))
|
||
return false;
|
||
break;
|
||
case eEncodingT3:
|
||
Rt = Bits32(opcode, 15, 12);
|
||
// if t == 13 || (t == 15 && InITBlock() && !LastInITBlock()) then UNPREDICTABLE;
|
||
if (Rt == dwarf_sp)
|
||
return false;
|
||
registers = (1u << Rt);
|
||
break;
|
||
case eEncodingA1:
|
||
registers = Bits32(opcode, 15, 0);
|
||
// Instead of return false, let's handle the following case as well,
|
||
// which amounts to popping one reg from the full descending stacks.
|
||
// if BitCount(register_list) < 2 then SEE LDM / LDMIA / LDMFD;
|
||
|
||
// if registers<13> == ‘1’ && ArchVersion() >= 7 then UNPREDICTABLE;
|
||
if (Bits32(opcode, 13, 13))
|
||
return false;
|
||
break;
|
||
case eEncodingA2:
|
||
Rt = Bits32(opcode, 15, 12);
|
||
// if t == 13 then UNPREDICTABLE;
|
||
if (Rt == dwarf_sp)
|
||
return false;
|
||
registers = (1u << Rt);
|
||
break;
|
||
default:
|
||
return false;
|
||
}
|
||
addr_t sp_offset = addr_byte_size * BitCount (registers);
|
||
addr_t addr = sp;
|
||
uint32_t i, data;
|
||
|
||
EmulateInstruction::Context context = { EmulateInstruction::eContextPopRegisterOffStack, eRegisterKindDWARF, 0, 0 };
|
||
for (i=0; i<15; ++i)
|
||
{
|
||
if (BitIsSet (registers, i))
|
||
{
|
||
context.arg1 = dwarf_r0 + i; // arg1 in the context is the DWARF register number
|
||
context.arg2 = addr - sp; // arg2 in the context is the stack pointer offset
|
||
data = ReadMemoryUnsigned(context, addr, 4, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
if (!WriteRegisterUnsigned(context, eRegisterKindDWARF, context.arg1, data))
|
||
return false;
|
||
addr += addr_byte_size;
|
||
}
|
||
}
|
||
|
||
if (BitIsSet (registers, 15))
|
||
{
|
||
context.arg1 = dwarf_pc; // arg1 in the context is the DWARF register number
|
||
context.arg2 = addr - sp; // arg2 in the context is the stack pointer offset
|
||
data = ReadMemoryUnsigned(context, addr, 4, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
if (!WriteRegisterUnsigned(context, eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC, data))
|
||
return false;
|
||
addr += addr_byte_size;
|
||
}
|
||
|
||
context.type = EmulateInstruction::eContextAdjustStackPointer;
|
||
context.arg0 = eRegisterKindGeneric;
|
||
context.arg1 = LLDB_REGNUM_GENERIC_SP;
|
||
context.arg2 = sp_offset;
|
||
|
||
if (!WriteRegisterUnsigned (context, eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP, sp + sp_offset))
|
||
return false;
|
||
}
|
||
return true;
|
||
}
|
||
|
||
// Set r7 or ip to point to saved value residing within the stack.
|
||
// ADD (SP plus immediate)
|
||
bool
|
||
EmulateInstructionARM::EmulateAddRdSPImmediate (ARMEncoding encoding)
|
||
{
|
||
#if 0
|
||
// ARM pseudo code...
|
||
if (ConditionPassed())
|
||
{
|
||
EncodingSpecificOperations();
|
||
(result, carry, overflow) = AddWithCarry(SP, imm32, ‘0’);
|
||
if d == 15 then
|
||
ALUWritePC(result); // setflags is always FALSE here
|
||
else
|
||
R[d] = result;
|
||
if setflags then
|
||
APSR.N = result<31>;
|
||
APSR.Z = IsZeroBit(result);
|
||
APSR.C = carry;
|
||
APSR.V = overflow;
|
||
}
|
||
#endif
|
||
|
||
bool success = false;
|
||
const uint32_t opcode = OpcodeAsUnsigned (&success);
|
||
if (!success)
|
||
return false;
|
||
|
||
if (ConditionPassed())
|
||
{
|
||
const addr_t sp = ReadRegisterUnsigned (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
uint32_t Rd; // the destination register
|
||
uint32_t imm32;
|
||
switch (encoding) {
|
||
case eEncodingT1:
|
||
Rd = 7;
|
||
imm32 = Bits32(opcode, 7, 0) << 2; // imm32 = ZeroExtend(imm8:'00', 32)
|
||
break;
|
||
case eEncodingA1:
|
||
Rd = Bits32(opcode, 15, 12);
|
||
imm32 = ARMExpandImm(opcode); // imm32 = ARMExpandImm(imm12)
|
||
break;
|
||
default:
|
||
return false;
|
||
}
|
||
addr_t sp_offset = imm32;
|
||
addr_t addr = sp + sp_offset; // a pointer to the stack area
|
||
|
||
EmulateInstruction::Context context = { EmulateInstruction::eContextRegisterPlusOffset,
|
||
eRegisterKindGeneric,
|
||
LLDB_REGNUM_GENERIC_SP,
|
||
sp_offset };
|
||
|
||
if (!WriteRegisterUnsigned (context, eRegisterKindDWARF, dwarf_r0 + Rd, addr))
|
||
return false;
|
||
}
|
||
return true;
|
||
}
|
||
|
||
// Set r7 or ip to the current stack pointer.
|
||
// MOV (register)
|
||
bool
|
||
EmulateInstructionARM::EmulateMovRdSP (ARMEncoding encoding)
|
||
{
|
||
#if 0
|
||
// ARM pseudo code...
|
||
if (ConditionPassed())
|
||
{
|
||
EncodingSpecificOperations();
|
||
result = R[m];
|
||
if d == 15 then
|
||
ALUWritePC(result); // setflags is always FALSE here
|
||
else
|
||
R[d] = result;
|
||
if setflags then
|
||
APSR.N = result<31>;
|
||
APSR.Z = IsZeroBit(result);
|
||
// APSR.C unchanged
|
||
// APSR.V unchanged
|
||
}
|
||
#endif
|
||
|
||
bool success = false;
|
||
//const uint32_t opcode = OpcodeAsUnsigned (&success);
|
||
//if (!success)
|
||
// return false;
|
||
|
||
if (ConditionPassed())
|
||
{
|
||
const addr_t sp = ReadRegisterUnsigned (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
uint32_t Rd; // the destination register
|
||
switch (encoding) {
|
||
case eEncodingT1:
|
||
Rd = 7;
|
||
break;
|
||
case eEncodingA1:
|
||
Rd = 12;
|
||
break;
|
||
default:
|
||
return false;
|
||
}
|
||
EmulateInstruction::Context context = { EmulateInstruction::eContextRegisterPlusOffset,
|
||
eRegisterKindGeneric,
|
||
LLDB_REGNUM_GENERIC_SP,
|
||
0 };
|
||
|
||
if (!WriteRegisterUnsigned (context, eRegisterKindDWARF, dwarf_r0 + Rd, sp))
|
||
return false;
|
||
}
|
||
return true;
|
||
}
|
||
|
||
// Move from high register (r8-r15) to low register (r0-r7).
|
||
// MOV (register)
|
||
bool
|
||
EmulateInstructionARM::EmulateMovLowHigh (ARMEncoding encoding)
|
||
{
|
||
#if 0
|
||
// ARM pseudo code...
|
||
if (ConditionPassed())
|
||
{
|
||
EncodingSpecificOperations();
|
||
result = R[m];
|
||
if d == 15 then
|
||
ALUWritePC(result); // setflags is always FALSE here
|
||
else
|
||
R[d] = result;
|
||
if setflags then
|
||
APSR.N = result<31>;
|
||
APSR.Z = IsZeroBit(result);
|
||
// APSR.C unchanged
|
||
// APSR.V unchanged
|
||
}
|
||
#endif
|
||
|
||
bool success = false;
|
||
const uint32_t opcode = OpcodeAsUnsigned (&success);
|
||
if (!success)
|
||
return false;
|
||
|
||
if (ConditionPassed())
|
||
{
|
||
uint32_t Rm; // the source register
|
||
uint32_t Rd; // the destination register
|
||
switch (encoding) {
|
||
case eEncodingT1:
|
||
Rm = Bits32(opcode, 6, 3);
|
||
Rd = Bits32(opcode, 2, 1); // bits(7) == 0
|
||
break;
|
||
default:
|
||
return false;
|
||
}
|
||
int32_t reg_value = ReadRegisterUnsigned(eRegisterKindDWARF, dwarf_r0 + Rm, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
|
||
// The context specifies that Rm is to be moved into Rd.
|
||
EmulateInstruction::Context context = { EmulateInstruction::eContextRegisterPlusOffset,
|
||
eRegisterKindDWARF,
|
||
dwarf_r0 + Rm,
|
||
0 };
|
||
|
||
if (!WriteRegisterUnsigned (context, eRegisterKindDWARF, dwarf_r0 + Rd, reg_value))
|
||
return false;
|
||
}
|
||
return true;
|
||
}
|
||
|
||
// PC relative immediate load into register, possibly followed by ADD (SP plus register).
|
||
// LDR (literal)
|
||
bool
|
||
EmulateInstructionARM::EmulateLDRRdPCRelative (ARMEncoding encoding)
|
||
{
|
||
#if 0
|
||
// ARM pseudo code...
|
||
if (ConditionPassed())
|
||
{
|
||
EncodingSpecificOperations(); NullCheckIfThumbEE(15);
|
||
base = Align(PC,4);
|
||
address = if add then (base + imm32) else (base - imm32);
|
||
data = MemU[address,4];
|
||
if t == 15 then
|
||
if address<1:0> == ‘00’ then LoadWritePC(data); else UNPREDICTABLE;
|
||
elsif UnalignedSupport() || address<1:0> = ‘00’ then
|
||
R[t] = data;
|
||
else // Can only apply before ARMv7
|
||
if CurrentInstrSet() == InstrSet_ARM then
|
||
R[t] = ROR(data, 8*UInt(address<1:0>));
|
||
else
|
||
R[t] = bits(32) UNKNOWN;
|
||
}
|
||
#endif
|
||
|
||
bool success = false;
|
||
const uint32_t opcode = OpcodeAsUnsigned (&success);
|
||
if (!success)
|
||
return false;
|
||
|
||
if (ConditionPassed())
|
||
{
|
||
const uint32_t pc = ReadRegisterUnsigned(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
|
||
// PC relative immediate load context
|
||
EmulateInstruction::Context context = {EmulateInstruction::eContextRegisterPlusOffset,
|
||
eRegisterKindGeneric,
|
||
LLDB_REGNUM_GENERIC_PC,
|
||
0};
|
||
uint32_t Rd; // the destination register
|
||
uint32_t imm32; // immediate offset from the PC
|
||
addr_t addr; // the PC relative address
|
||
uint32_t data; // the literal data value from the PC relative load
|
||
switch (encoding) {
|
||
case eEncodingT1:
|
||
Rd = Bits32(opcode, 10, 8);
|
||
imm32 = Bits32(opcode, 7, 0) << 2; // imm32 = ZeroExtend(imm8:'00', 32);
|
||
addr = pc + 4 + imm32;
|
||
context.arg2 = 4 + imm32;
|
||
break;
|
||
default:
|
||
return false;
|
||
}
|
||
data = ReadMemoryUnsigned(context, addr, 4, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
if (!WriteRegisterUnsigned (context, eRegisterKindDWARF, dwarf_r0 + Rd, data))
|
||
return false;
|
||
}
|
||
return true;
|
||
}
|
||
|
||
// An add operation to adjust the SP.
|
||
// ADD (SP plus immediate)
|
||
bool
|
||
EmulateInstructionARM::EmulateAddSPImmediate (ARMEncoding encoding)
|
||
{
|
||
#if 0
|
||
// ARM pseudo code...
|
||
if (ConditionPassed())
|
||
{
|
||
EncodingSpecificOperations();
|
||
(result, carry, overflow) = AddWithCarry(SP, imm32, ‘0’);
|
||
if d == 15 then // Can only occur for ARM encoding
|
||
ALUWritePC(result); // setflags is always FALSE here
|
||
else
|
||
R[d] = result;
|
||
if setflags then
|
||
APSR.N = result<31>;
|
||
APSR.Z = IsZeroBit(result);
|
||
APSR.C = carry;
|
||
APSR.V = overflow;
|
||
}
|
||
#endif
|
||
|
||
bool success = false;
|
||
const uint32_t opcode = OpcodeAsUnsigned (&success);
|
||
if (!success)
|
||
return false;
|
||
|
||
if (ConditionPassed())
|
||
{
|
||
const addr_t sp = ReadRegisterUnsigned (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
uint32_t imm32; // the immediate operand
|
||
switch (encoding) {
|
||
case eEncodingT2:
|
||
imm32 = ThumbImmScaled(opcode); // imm32 = ZeroExtend(imm7:'00', 32)
|
||
break;
|
||
default:
|
||
return false;
|
||
}
|
||
addr_t sp_offset = imm32;
|
||
addr_t addr = sp + sp_offset; // the adjusted stack pointer value
|
||
|
||
EmulateInstruction::Context context = { EmulateInstruction::eContextAdjustStackPointer,
|
||
eRegisterKindGeneric,
|
||
LLDB_REGNUM_GENERIC_SP,
|
||
sp_offset };
|
||
|
||
if (!WriteRegisterUnsigned (context, eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP, addr))
|
||
return false;
|
||
}
|
||
return true;
|
||
}
|
||
|
||
// An add operation to adjust the SP.
|
||
// ADD (SP plus register)
|
||
bool
|
||
EmulateInstructionARM::EmulateAddSPRm (ARMEncoding encoding)
|
||
{
|
||
#if 0
|
||
// ARM pseudo code...
|
||
if (ConditionPassed())
|
||
{
|
||
EncodingSpecificOperations();
|
||
shifted = Shift(R[m], shift_t, shift_n, APSR.C);
|
||
(result, carry, overflow) = AddWithCarry(SP, shifted, ‘0’);
|
||
if d == 15 then
|
||
ALUWritePC(result); // setflags is always FALSE here
|
||
else
|
||
R[d] = result;
|
||
if setflags then
|
||
APSR.N = result<31>;
|
||
APSR.Z = IsZeroBit(result);
|
||
APSR.C = carry;
|
||
APSR.V = overflow;
|
||
}
|
||
#endif
|
||
|
||
bool success = false;
|
||
const uint32_t opcode = OpcodeAsUnsigned (&success);
|
||
if (!success)
|
||
return false;
|
||
|
||
if (ConditionPassed())
|
||
{
|
||
const addr_t sp = ReadRegisterUnsigned (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
uint32_t Rm; // the second operand
|
||
switch (encoding) {
|
||
case eEncodingT2:
|
||
Rm = Bits32(opcode, 6, 3);
|
||
break;
|
||
default:
|
||
return false;
|
||
}
|
||
int32_t reg_value = ReadRegisterUnsigned(eRegisterKindDWARF, dwarf_r0 + Rm, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
|
||
addr_t addr = (int32_t)sp + reg_value; // the adjusted stack pointer value
|
||
|
||
EmulateInstruction::Context context = { EmulateInstruction::eContextAdjustStackPointer,
|
||
eRegisterKindGeneric,
|
||
LLDB_REGNUM_GENERIC_SP,
|
||
reg_value };
|
||
|
||
if (!WriteRegisterUnsigned (context, eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP, addr))
|
||
return false;
|
||
}
|
||
return true;
|
||
}
|
||
|
||
// Branch with Link and Exchange Instruction Sets (immediate) calls a subroutine
|
||
// at a PC-relative address, and changes instruction set from ARM to Thumb, or
|
||
// from Thumb to ARM.
|
||
// BLX (immediate)
|
||
bool
|
||
EmulateInstructionARM::EmulateBLXImmediate (ARMEncoding encoding)
|
||
{
|
||
#if 0
|
||
// ARM pseudo code...
|
||
if (ConditionPassed())
|
||
{
|
||
EncodingSpecificOperations();
|
||
if CurrentInstrSet() == InstrSet_ARM then
|
||
LR = PC - 4;
|
||
else
|
||
LR = PC<31:1> : '1';
|
||
if targetInstrSet == InstrSet_ARM then
|
||
targetAddress = Align(PC,4) + imm32;
|
||
else
|
||
targetAddress = PC + imm32;
|
||
SelectInstrSet(targetInstrSet);
|
||
BranchWritePC(targetAddress);
|
||
}
|
||
#endif
|
||
|
||
bool success = false;
|
||
const uint32_t opcode = OpcodeAsUnsigned (&success);
|
||
if (!success)
|
||
return false;
|
||
|
||
if (ConditionPassed())
|
||
{
|
||
EmulateInstruction::Context context = { EmulateInstruction::eContextRelativeBranchImmediate, 0, 0, 0};
|
||
const uint32_t pc = ReadRegisterUnsigned(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
addr_t lr; // next instruction address
|
||
addr_t target; // target address
|
||
int32_t imm32; // PC-relative offset
|
||
switch (encoding) {
|
||
case eEncodingT1:
|
||
{
|
||
lr = (pc + 4) | 1u; // return address
|
||
uint32_t S = Bits32(opcode, 26, 26);
|
||
uint32_t imm10 = Bits32(opcode, 25, 16);
|
||
uint32_t J1 = Bits32(opcode, 13, 13);
|
||
uint32_t J2 = Bits32(opcode, 11, 11);
|
||
uint32_t imm11 = Bits32(opcode, 10, 0);
|
||
uint32_t I1 = !(J1 ^ S);
|
||
uint32_t I2 = !(J2 ^ S);
|
||
uint32_t imm25 = (S << 24) | (I1 << 23) | (I2 << 22) | (imm10 << 12) | (imm11 << 1);
|
||
imm32 = llvm::SignExtend32<25>(imm25);
|
||
target = pc + 4 + imm32;
|
||
context.arg1 = 4 + imm32; // signed offset
|
||
context.arg2 = eModeThumb; // target instruction set
|
||
break;
|
||
}
|
||
case eEncodingT2:
|
||
{
|
||
lr = (pc + 4) | 1u; // return address
|
||
uint32_t S = Bits32(opcode, 26, 26);
|
||
uint32_t imm10H = Bits32(opcode, 25, 16);
|
||
uint32_t J1 = Bits32(opcode, 13, 13);
|
||
uint32_t J2 = Bits32(opcode, 11, 11);
|
||
uint32_t imm10L = Bits32(opcode, 10, 1);
|
||
uint32_t I1 = !(J1 ^ S);
|
||
uint32_t I2 = !(J2 ^ S);
|
||
uint32_t imm25 = (S << 24) | (I1 << 23) | (I2 << 22) | (imm10H << 12) | (imm10L << 2);
|
||
imm32 = llvm::SignExtend32<25>(imm25);
|
||
target = Align(pc + 4, 4) + imm32;
|
||
context.arg1 = 4 + imm32; // signed offset
|
||
context.arg2 = eModeARM; // target instruction set
|
||
break;
|
||
}
|
||
case eEncodingA1:
|
||
lr = pc + 4; // return address
|
||
imm32 = llvm::SignExtend32<26>(Bits32(opcode, 23, 0) << 2);
|
||
target = Align(pc + 8, 4) + imm32;
|
||
context.arg1 = 8 + imm32; // signed offset
|
||
context.arg2 = eModeARM; // target instruction set
|
||
break;
|
||
case eEncodingA2:
|
||
lr = pc + 4; // return address
|
||
imm32 = llvm::SignExtend32<26>(Bits32(opcode, 23, 0) << 2 | Bits32(opcode, 24, 24) << 1);
|
||
target = pc + 8 + imm32;
|
||
context.arg1 = 8 + imm32; // signed offset
|
||
context.arg2 = eModeThumb; // target instruction set
|
||
break;
|
||
default:
|
||
return false;
|
||
}
|
||
if (!WriteRegisterUnsigned (context, eRegisterKindGeneric, LLDB_REGNUM_GENERIC_RA, lr))
|
||
return false;
|
||
if (!BranchWritePC(context, target))
|
||
return false;
|
||
}
|
||
return true;
|
||
}
|
||
|
||
// Branch with Link and Exchange (register) calls a subroutine at an address and
|
||
// instruction set specified by a register.
|
||
// BLX (register)
|
||
bool
|
||
EmulateInstructionARM::EmulateBLXRm (ARMEncoding encoding)
|
||
{
|
||
#if 0
|
||
// ARM pseudo code...
|
||
if (ConditionPassed())
|
||
{
|
||
EncodingSpecificOperations();
|
||
target = R[m];
|
||
if CurrentInstrSet() == InstrSet_ARM then
|
||
next_instr_addr = PC - 4;
|
||
LR = next_instr_addr;
|
||
else
|
||
next_instr_addr = PC - 2;
|
||
LR = next_instr_addr<31:1> : ‘1’;
|
||
BXWritePC(target);
|
||
}
|
||
#endif
|
||
|
||
bool success = false;
|
||
const uint32_t opcode = OpcodeAsUnsigned (&success);
|
||
if (!success)
|
||
return false;
|
||
|
||
if (ConditionPassed())
|
||
{
|
||
EmulateInstruction::Context context = { EmulateInstruction::eContextAbsoluteBranchRegister, 0, 0, 0};
|
||
const uint32_t pc = ReadRegisterUnsigned(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC, 0, &success);
|
||
addr_t lr; // next instruction address
|
||
addr_t target; // target address
|
||
if (!success)
|
||
return false;
|
||
uint32_t Rm; // the register with the target address
|
||
switch (encoding) {
|
||
case eEncodingT1:
|
||
lr = (pc + 2) | 1u; // return address
|
||
Rm = Bits32(opcode, 6, 3);
|
||
// if m == 15 then UNPREDICTABLE;
|
||
if (Rm == 15)
|
||
return false;
|
||
target = ReadRegisterUnsigned (eRegisterKindDWARF, dwarf_r0 + Rm, 0, &success);
|
||
break;
|
||
case eEncodingA1:
|
||
lr = pc + 4; // return address
|
||
Rm = Bits32(opcode, 3, 0);
|
||
// if m == 15 then UNPREDICTABLE;
|
||
if (Rm == 15)
|
||
return false;
|
||
target = ReadRegisterUnsigned (eRegisterKindDWARF, dwarf_r0 + Rm, 0, &success);
|
||
break;
|
||
default:
|
||
return false;
|
||
}
|
||
context.arg0 = eRegisterKindDWARF;
|
||
context.arg1 = dwarf_r0 + Rm;
|
||
if (!WriteRegisterUnsigned (context, eRegisterKindGeneric, LLDB_REGNUM_GENERIC_RA, lr))
|
||
return false;
|
||
if (!BXWritePC(context, target))
|
||
return false;
|
||
}
|
||
return true;
|
||
}
|
||
|
||
// Set r7 to point to some ip offset.
|
||
// SUB (immediate)
|
||
bool
|
||
EmulateInstructionARM::EmulateSubR7IPImmediate (ARMEncoding encoding)
|
||
{
|
||
#if 0
|
||
// ARM pseudo code...
|
||
if (ConditionPassed())
|
||
{
|
||
EncodingSpecificOperations();
|
||
(result, carry, overflow) = AddWithCarry(SP, NOT(imm32), ‘1’);
|
||
if d == 15 then // Can only occur for ARM encoding
|
||
ALUWritePC(result); // setflags is always FALSE here
|
||
else
|
||
R[d] = result;
|
||
if setflags then
|
||
APSR.N = result<31>;
|
||
APSR.Z = IsZeroBit(result);
|
||
APSR.C = carry;
|
||
APSR.V = overflow;
|
||
}
|
||
#endif
|
||
|
||
bool success = false;
|
||
const uint32_t opcode = OpcodeAsUnsigned (&success);
|
||
if (!success)
|
||
return false;
|
||
|
||
if (ConditionPassed())
|
||
{
|
||
const addr_t ip = ReadRegisterUnsigned (eRegisterKindDWARF, dwarf_r12, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
uint32_t imm32;
|
||
switch (encoding) {
|
||
case eEncodingA1:
|
||
imm32 = ARMExpandImm(opcode); // imm32 = ARMExpandImm(imm12)
|
||
break;
|
||
default:
|
||
return false;
|
||
}
|
||
addr_t ip_offset = imm32;
|
||
addr_t addr = ip - ip_offset; // the adjusted ip value
|
||
|
||
EmulateInstruction::Context context = { EmulateInstruction::eContextRegisterPlusOffset,
|
||
eRegisterKindDWARF,
|
||
dwarf_r12,
|
||
-ip_offset };
|
||
|
||
if (!WriteRegisterUnsigned (context, eRegisterKindDWARF, dwarf_r7, addr))
|
||
return false;
|
||
}
|
||
return true;
|
||
}
|
||
|
||
// Set ip to point to some stack offset.
|
||
// SUB (SP minus immediate)
|
||
bool
|
||
EmulateInstructionARM::EmulateSubIPSPImmediate (ARMEncoding encoding)
|
||
{
|
||
#if 0
|
||
// ARM pseudo code...
|
||
if (ConditionPassed())
|
||
{
|
||
EncodingSpecificOperations();
|
||
(result, carry, overflow) = AddWithCarry(SP, NOT(imm32), ‘1’);
|
||
if d == 15 then // Can only occur for ARM encoding
|
||
ALUWritePC(result); // setflags is always FALSE here
|
||
else
|
||
R[d] = result;
|
||
if setflags then
|
||
APSR.N = result<31>;
|
||
APSR.Z = IsZeroBit(result);
|
||
APSR.C = carry;
|
||
APSR.V = overflow;
|
||
}
|
||
#endif
|
||
|
||
bool success = false;
|
||
const uint32_t opcode = OpcodeAsUnsigned (&success);
|
||
if (!success)
|
||
return false;
|
||
|
||
if (ConditionPassed())
|
||
{
|
||
const addr_t sp = ReadRegisterUnsigned (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
uint32_t imm32;
|
||
switch (encoding) {
|
||
case eEncodingA1:
|
||
imm32 = ARMExpandImm(opcode); // imm32 = ARMExpandImm(imm12)
|
||
break;
|
||
default:
|
||
return false;
|
||
}
|
||
addr_t sp_offset = imm32;
|
||
addr_t addr = sp - sp_offset; // the adjusted stack pointer value
|
||
|
||
EmulateInstruction::Context context = { EmulateInstruction::eContextRegisterPlusOffset,
|
||
eRegisterKindGeneric,
|
||
LLDB_REGNUM_GENERIC_SP,
|
||
-sp_offset };
|
||
|
||
if (!WriteRegisterUnsigned (context, eRegisterKindDWARF, dwarf_r12, addr))
|
||
return false;
|
||
}
|
||
return true;
|
||
}
|
||
|
||
// A sub operation to adjust the SP -- allocate space for local storage.
|
||
bool
|
||
EmulateInstructionARM::EmulateSubSPImmdiate (ARMEncoding encoding)
|
||
{
|
||
#if 0
|
||
// ARM pseudo code...
|
||
if (ConditionPassed())
|
||
{
|
||
EncodingSpecificOperations();
|
||
(result, carry, overflow) = AddWithCarry(SP, NOT(imm32), ‘1’);
|
||
if d == 15 then // Can only occur for ARM encoding
|
||
ALUWritePC(result); // setflags is always FALSE here
|
||
else
|
||
R[d] = result;
|
||
if setflags then
|
||
APSR.N = result<31>;
|
||
APSR.Z = IsZeroBit(result);
|
||
APSR.C = carry;
|
||
APSR.V = overflow;
|
||
}
|
||
#endif
|
||
|
||
bool success = false;
|
||
const uint32_t opcode = OpcodeAsUnsigned (&success);
|
||
if (!success)
|
||
return false;
|
||
|
||
if (ConditionPassed())
|
||
{
|
||
const addr_t sp = ReadRegisterUnsigned (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
uint32_t imm32;
|
||
switch (encoding) {
|
||
case eEncodingT1:
|
||
imm32 = ThumbImmScaled(opcode); // imm32 = ZeroExtend(imm7:'00', 32)
|
||
case eEncodingT2:
|
||
imm32 = ThumbExpandImm(opcode); // imm32 = ThumbExpandImm(i:imm3:imm8)
|
||
break;
|
||
case eEncodingT3:
|
||
imm32 = ThumbImm12(opcode); // imm32 = ZeroExtend(i:imm3:imm8, 32)
|
||
break;
|
||
case eEncodingA1:
|
||
imm32 = ARMExpandImm(opcode); // imm32 = ARMExpandImm(imm12)
|
||
break;
|
||
default:
|
||
return false;
|
||
}
|
||
addr_t sp_offset = imm32;
|
||
addr_t addr = sp - sp_offset; // the adjusted stack pointer value
|
||
|
||
EmulateInstruction::Context context = { EmulateInstruction::eContextAdjustStackPointer,
|
||
eRegisterKindGeneric,
|
||
LLDB_REGNUM_GENERIC_SP,
|
||
-sp_offset };
|
||
|
||
if (!WriteRegisterUnsigned (context, eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP, addr))
|
||
return false;
|
||
}
|
||
return true;
|
||
}
|
||
|
||
// A store operation to the stack that also updates the SP.
|
||
bool
|
||
EmulateInstructionARM::EmulateSTRRtSP (ARMEncoding encoding)
|
||
{
|
||
#if 0
|
||
// ARM pseudo code...
|
||
if (ConditionPassed())
|
||
{
|
||
EncodingSpecificOperations();
|
||
offset_addr = if add then (R[n] + imm32) else (R[n] - imm32);
|
||
address = if index then offset_addr else R[n];
|
||
MemU[address,4] = if t == 15 then PCStoreValue() else R[t];
|
||
if wback then R[n] = offset_addr;
|
||
}
|
||
#endif
|
||
|
||
bool success = false;
|
||
const uint32_t opcode = OpcodeAsUnsigned (&success);
|
||
if (!success)
|
||
return false;
|
||
|
||
if (ConditionPassed())
|
||
{
|
||
const uint32_t addr_byte_size = GetAddressByteSize();
|
||
const addr_t sp = ReadRegisterUnsigned (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
uint32_t Rt; // the source register
|
||
uint32_t imm12;
|
||
switch (encoding) {
|
||
case eEncodingA1:
|
||
Rt = Bits32(opcode, 15, 12);
|
||
imm12 = Bits32(opcode, 11, 0);
|
||
break;
|
||
default:
|
||
return false;
|
||
}
|
||
addr_t sp_offset = imm12;
|
||
addr_t addr = sp - sp_offset;
|
||
|
||
EmulateInstruction::Context context = { EmulateInstruction::eContextPushRegisterOnStack, eRegisterKindDWARF, 0, 0 };
|
||
if (Rt != 15)
|
||
{
|
||
context.arg1 = dwarf_r0 + Rt; // arg1 in the context is the DWARF register number
|
||
context.arg2 = addr - sp; // arg2 in the context is the stack pointer offset
|
||
uint32_t reg_value = ReadRegisterUnsigned(eRegisterKindDWARF, context.arg1, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
if (!WriteMemoryUnsigned (context, addr, reg_value, addr_byte_size))
|
||
return false;
|
||
}
|
||
else
|
||
{
|
||
context.arg1 = dwarf_pc; // arg1 in the context is the DWARF register number
|
||
context.arg2 = addr - sp; // arg2 in the context is the stack pointer offset
|
||
const uint32_t pc = ReadRegisterUnsigned(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
if (!WriteMemoryUnsigned (context, addr, pc + 8, addr_byte_size))
|
||
return false;
|
||
}
|
||
|
||
context.type = EmulateInstruction::eContextAdjustStackPointer;
|
||
context.arg0 = eRegisterKindGeneric;
|
||
context.arg1 = LLDB_REGNUM_GENERIC_SP;
|
||
context.arg2 = -sp_offset;
|
||
|
||
if (!WriteRegisterUnsigned (context, eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP, sp - sp_offset))
|
||
return false;
|
||
}
|
||
return true;
|
||
}
|
||
|
||
// Vector Push stores multiple extension registers to the stack.
|
||
// It also updates SP to point to the start of the stored data.
|
||
bool
|
||
EmulateInstructionARM::EmulateVPUSH (ARMEncoding encoding)
|
||
{
|
||
#if 0
|
||
// ARM pseudo code...
|
||
if (ConditionPassed())
|
||
{
|
||
EncodingSpecificOperations(); CheckVFPEnabled(TRUE); NullCheckIfThumbEE(13);
|
||
address = SP - imm32;
|
||
SP = SP - imm32;
|
||
if single_regs then
|
||
for r = 0 to regs-1
|
||
MemA[address,4] = S[d+r]; address = address+4;
|
||
else
|
||
for r = 0 to regs-1
|
||
// Store as two word-aligned words in the correct order for current endianness.
|
||
MemA[address,4] = if BigEndian() then D[d+r]<63:32> else D[d+r]<31:0>;
|
||
MemA[address+4,4] = if BigEndian() then D[d+r]<31:0> else D[d+r]<63:32>;
|
||
address = address+8;
|
||
}
|
||
#endif
|
||
|
||
bool success = false;
|
||
const uint32_t opcode = OpcodeAsUnsigned (&success);
|
||
if (!success)
|
||
return false;
|
||
|
||
if (ConditionPassed())
|
||
{
|
||
const uint32_t addr_byte_size = GetAddressByteSize();
|
||
const addr_t sp = ReadRegisterUnsigned (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
bool single_regs;
|
||
uint32_t d; // UInt(D:Vd) or UInt(Vd:D) starting register
|
||
uint32_t imm32; // stack offset
|
||
uint32_t regs; // number of registers
|
||
switch (encoding) {
|
||
case eEncodingT1:
|
||
case eEncodingA1:
|
||
single_regs = false;
|
||
d = Bits32(opcode, 22, 22) << 4 | Bits32(opcode, 15, 12);
|
||
imm32 = Bits32(opcode, 7, 0) * addr_byte_size;
|
||
// If UInt(imm8) is odd, see "FSTMX".
|
||
regs = Bits32(opcode, 7, 0) / 2;
|
||
// if regs == 0 || regs > 16 || (d+regs) > 32 then UNPREDICTABLE;
|
||
if (regs == 0 || regs > 16 || (d + regs) > 32)
|
||
return false;
|
||
break;
|
||
case eEncodingT2:
|
||
case eEncodingA2:
|
||
single_regs = true;
|
||
d = Bits32(opcode, 15, 12) << 1 | Bits32(opcode, 22, 22);
|
||
imm32 = Bits32(opcode, 7, 0) * addr_byte_size;
|
||
regs = Bits32(opcode, 7, 0);
|
||
// if regs == 0 || regs > 16 || (d+regs) > 32 then UNPREDICTABLE;
|
||
if (regs == 0 || regs > 16 || (d + regs) > 32)
|
||
return false;
|
||
break;
|
||
default:
|
||
return false;
|
||
}
|
||
uint32_t start_reg = single_regs ? dwarf_s0 : dwarf_d0;
|
||
uint32_t reg_byte_size = single_regs ? addr_byte_size : addr_byte_size * 2;
|
||
addr_t sp_offset = imm32;
|
||
addr_t addr = sp - sp_offset;
|
||
uint32_t i;
|
||
|
||
EmulateInstruction::Context context = { EmulateInstruction::eContextPushRegisterOnStack, eRegisterKindDWARF, 0, 0 };
|
||
for (i=d; i<regs; ++i)
|
||
{
|
||
context.arg1 = start_reg + i; // arg1 in the context is the DWARF register number
|
||
context.arg2 = addr - sp; // arg2 in the context is the stack pointer offset
|
||
// uint64_t to accommodate 64-bit registers.
|
||
uint64_t reg_value = ReadRegisterUnsigned(eRegisterKindDWARF, context.arg1, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
if (!WriteMemoryUnsigned (context, addr, reg_value, reg_byte_size))
|
||
return false;
|
||
addr += reg_byte_size;
|
||
}
|
||
|
||
context.type = EmulateInstruction::eContextAdjustStackPointer;
|
||
context.arg0 = eRegisterKindGeneric;
|
||
context.arg1 = LLDB_REGNUM_GENERIC_SP;
|
||
context.arg2 = -sp_offset;
|
||
|
||
if (!WriteRegisterUnsigned (context, eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP, sp - sp_offset))
|
||
return false;
|
||
}
|
||
return true;
|
||
}
|
||
|
||
// Vector Pop loads multiple extension registers from the stack.
|
||
// It also updates SP to point just above the loaded data.
|
||
bool
|
||
EmulateInstructionARM::EmulateVPOP (ARMEncoding encoding)
|
||
{
|
||
#if 0
|
||
// ARM pseudo code...
|
||
if (ConditionPassed())
|
||
{
|
||
EncodingSpecificOperations(); CheckVFPEnabled(TRUE); NullCheckIfThumbEE(13);
|
||
address = SP;
|
||
SP = SP + imm32;
|
||
if single_regs then
|
||
for r = 0 to regs-1
|
||
S[d+r] = MemA[address,4]; address = address+4;
|
||
else
|
||
for r = 0 to regs-1
|
||
word1 = MemA[address,4]; word2 = MemA[address+4,4]; address = address+8;
|
||
// Combine the word-aligned words in the correct order for current endianness.
|
||
D[d+r] = if BigEndian() then word1:word2 else word2:word1;
|
||
}
|
||
#endif
|
||
|
||
bool success = false;
|
||
const uint32_t opcode = OpcodeAsUnsigned (&success);
|
||
if (!success)
|
||
return false;
|
||
|
||
if (ConditionPassed())
|
||
{
|
||
const uint32_t addr_byte_size = GetAddressByteSize();
|
||
const addr_t sp = ReadRegisterUnsigned (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
bool single_regs;
|
||
uint32_t d; // UInt(D:Vd) or UInt(Vd:D) starting register
|
||
uint32_t imm32; // stack offset
|
||
uint32_t regs; // number of registers
|
||
switch (encoding) {
|
||
case eEncodingT1:
|
||
case eEncodingA1:
|
||
single_regs = false;
|
||
d = Bits32(opcode, 22, 22) << 4 | Bits32(opcode, 15, 12);
|
||
imm32 = Bits32(opcode, 7, 0) * addr_byte_size;
|
||
// If UInt(imm8) is odd, see "FLDMX".
|
||
regs = Bits32(opcode, 7, 0) / 2;
|
||
// if regs == 0 || regs > 16 || (d+regs) > 32 then UNPREDICTABLE;
|
||
if (regs == 0 || regs > 16 || (d + regs) > 32)
|
||
return false;
|
||
break;
|
||
case eEncodingT2:
|
||
case eEncodingA2:
|
||
single_regs = true;
|
||
d = Bits32(opcode, 15, 12) << 1 | Bits32(opcode, 22, 22);
|
||
imm32 = Bits32(opcode, 7, 0) * addr_byte_size;
|
||
regs = Bits32(opcode, 7, 0);
|
||
// if regs == 0 || regs > 16 || (d+regs) > 32 then UNPREDICTABLE;
|
||
if (regs == 0 || regs > 16 || (d + regs) > 32)
|
||
return false;
|
||
break;
|
||
default:
|
||
return false;
|
||
}
|
||
uint32_t start_reg = single_regs ? dwarf_s0 : dwarf_d0;
|
||
uint32_t reg_byte_size = single_regs ? addr_byte_size : addr_byte_size * 2;
|
||
addr_t sp_offset = imm32;
|
||
addr_t addr = sp;
|
||
uint32_t i;
|
||
uint64_t data; // uint64_t to accomodate 64-bit registers.
|
||
|
||
EmulateInstruction::Context context = { EmulateInstruction::eContextPopRegisterOffStack, eRegisterKindDWARF, 0, 0 };
|
||
for (i=d; i<regs; ++i)
|
||
{
|
||
context.arg1 = start_reg + i; // arg1 in the context is the DWARF register number
|
||
context.arg2 = addr - sp; // arg2 in the context is the stack pointer offset
|
||
data = ReadMemoryUnsigned(context, addr, reg_byte_size, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
if (!WriteRegisterUnsigned(context, eRegisterKindDWARF, context.arg1, data))
|
||
return false;
|
||
addr += reg_byte_size;
|
||
}
|
||
|
||
context.type = EmulateInstruction::eContextAdjustStackPointer;
|
||
context.arg0 = eRegisterKindGeneric;
|
||
context.arg1 = LLDB_REGNUM_GENERIC_SP;
|
||
context.arg2 = sp_offset;
|
||
|
||
if (!WriteRegisterUnsigned (context, eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP, sp + sp_offset))
|
||
return false;
|
||
}
|
||
return true;
|
||
}
|
||
|
||
// SVC (previously SWI)
|
||
bool
|
||
EmulateInstructionARM::EmulateSVC (ARMEncoding encoding)
|
||
{
|
||
#if 0
|
||
// ARM pseudo code...
|
||
if (ConditionPassed())
|
||
{
|
||
EncodingSpecificOperations();
|
||
CallSupervisor();
|
||
}
|
||
#endif
|
||
|
||
bool success = false;
|
||
const uint32_t opcode = OpcodeAsUnsigned (&success);
|
||
if (!success)
|
||
return false;
|
||
|
||
if (ConditionPassed())
|
||
{
|
||
const uint32_t pc = ReadRegisterUnsigned(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC, 0, &success);
|
||
addr_t lr; // next instruction address
|
||
if (!success)
|
||
return false;
|
||
uint32_t imm32; // the immediate constant
|
||
uint32_t mode; // ARM or Thumb mode
|
||
switch (encoding) {
|
||
case eEncodingT1:
|
||
lr = (pc + 2) | 1u; // return address
|
||
imm32 = Bits32(opcode, 7, 0);
|
||
mode = eModeThumb;
|
||
break;
|
||
case eEncodingA1:
|
||
lr = pc + 4; // return address
|
||
imm32 = Bits32(opcode, 23, 0);
|
||
mode = eModeARM;
|
||
break;
|
||
default:
|
||
return false;
|
||
}
|
||
EmulateInstruction::Context context = { EmulateInstruction::eContextSupervisorCall, mode, imm32, 0};
|
||
if (!WriteRegisterUnsigned (context, eRegisterKindGeneric, LLDB_REGNUM_GENERIC_RA, lr))
|
||
return false;
|
||
}
|
||
return true;
|
||
}
|
||
|
||
// If Then makes up to four following instructions (the IT block) conditional.
|
||
bool
|
||
EmulateInstructionARM::EmulateIT (ARMEncoding encoding)
|
||
{
|
||
#if 0
|
||
// ARM pseudo code...
|
||
EncodingSpecificOperations();
|
||
ITSTATE.IT<7:0> = firstcond:mask;
|
||
#endif
|
||
|
||
bool success = false;
|
||
const uint32_t opcode = OpcodeAsUnsigned (&success);
|
||
if (!success)
|
||
return false;
|
||
|
||
m_it_session.InitIT(Bits32(opcode, 7, 0));
|
||
return true;
|
||
}
|
||
|
||
// Branch causes a branch to a target address.
|
||
bool
|
||
EmulateInstructionARM::EmulateB (ARMEncoding encoding)
|
||
{
|
||
#if 0
|
||
// ARM pseudo code...
|
||
if (ConditionPassed())
|
||
{
|
||
EncodingSpecificOperations();
|
||
BranchWritePC(PC + imm32);
|
||
}
|
||
#endif
|
||
|
||
bool success = false;
|
||
const uint32_t opcode = OpcodeAsUnsigned (&success);
|
||
if (!success)
|
||
return false;
|
||
|
||
if (ConditionPassed())
|
||
{
|
||
EmulateInstruction::Context context = { EmulateInstruction::eContextRelativeBranchImmediate, 0, 0, 0};
|
||
const uint32_t pc = ReadRegisterUnsigned(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
addr_t target; // target address
|
||
int32_t imm32; // PC-relative offset
|
||
switch (encoding) {
|
||
case eEncodingT1:
|
||
// The 'cond' field is handled in EmulateInstructionARM::CurrentCond().
|
||
imm32 = llvm::SignExtend32<9>(Bits32(opcode, 7, 0) << 1);
|
||
target = pc + 4 + imm32;
|
||
context.arg1 = 4 + imm32; // signed offset
|
||
context.arg2 = eModeThumb; // target instruction set
|
||
break;
|
||
case eEncodingT2:
|
||
imm32 = llvm::SignExtend32<12>(Bits32(opcode, 10, 0));
|
||
target = pc + 4 + imm32;
|
||
context.arg1 = 4 + imm32; // signed offset
|
||
context.arg2 = eModeThumb; // target instruction set
|
||
break;
|
||
case eEncodingT3:
|
||
// The 'cond' field is handled in EmulateInstructionARM::CurrentCond().
|
||
{
|
||
uint32_t S = Bits32(opcode, 26, 26);
|
||
uint32_t imm6 = Bits32(opcode, 21, 16);
|
||
uint32_t J1 = Bits32(opcode, 13, 13);
|
||
uint32_t J2 = Bits32(opcode, 11, 11);
|
||
uint32_t imm11 = Bits32(opcode, 10, 0);
|
||
uint32_t imm21 = (S << 20) | (J2 << 19) | (J1 << 18) | (imm6 << 12) | (imm11 << 1);
|
||
imm32 = llvm::SignExtend32<21>(imm21);
|
||
target = pc + 4 + imm32;
|
||
context.arg1 = eModeThumb; // target instruction set
|
||
context.arg2 = 4 + imm32; // signed offset
|
||
break;
|
||
}
|
||
case eEncodingT4:
|
||
{
|
||
uint32_t S = Bits32(opcode, 26, 26);
|
||
uint32_t imm10 = Bits32(opcode, 25, 16);
|
||
uint32_t J1 = Bits32(opcode, 13, 13);
|
||
uint32_t J2 = Bits32(opcode, 11, 11);
|
||
uint32_t imm11 = Bits32(opcode, 10, 0);
|
||
uint32_t I1 = !(J1 ^ S);
|
||
uint32_t I2 = !(J2 ^ S);
|
||
uint32_t imm25 = (S << 24) | (I1 << 23) | (I2 << 22) | (imm10 << 12) | (imm11 << 1);
|
||
imm32 = llvm::SignExtend32<25>(imm25);
|
||
target = pc + 4 + imm32;
|
||
context.arg1 = eModeThumb; // target instruction set
|
||
context.arg2 = 4 + imm32; // signed offset
|
||
break;
|
||
}
|
||
case eEncodingA1:
|
||
imm32 = llvm::SignExtend32<26>(Bits32(opcode, 23, 0) << 2);
|
||
target = pc + 8 + imm32;
|
||
context.arg1 = eModeARM; // target instruction set
|
||
context.arg2 = 8 + imm32; // signed offset
|
||
break;
|
||
default:
|
||
return false;
|
||
}
|
||
if (!BranchWritePC(context, target))
|
||
return false;
|
||
}
|
||
return true;
|
||
}
|
||
|
||
// Compare and Branch on Nonzero and Compare and Branch on Zero compare the value in a register with
|
||
// zero and conditionally branch forward a constant value. They do not affect the condition flags.
|
||
// CBNZ, CBZ
|
||
bool
|
||
EmulateInstructionARM::EmulateCB (ARMEncoding encoding)
|
||
{
|
||
#if 0
|
||
// ARM pseudo code...
|
||
EncodingSpecificOperations();
|
||
if nonzero ^ IsZero(R[n]) then
|
||
BranchWritePC(PC + imm32);
|
||
#endif
|
||
|
||
bool success = false;
|
||
const uint32_t opcode = OpcodeAsUnsigned (&success);
|
||
if (!success)
|
||
return false;
|
||
|
||
// Read the register value from the operand register Rn.
|
||
uint32_t reg_val = ReadRegisterUnsigned(eRegisterKindDWARF, dwarf_r0 + Bits32(opcode, 2, 0), 0, &success);
|
||
if (!success)
|
||
return false;
|
||
|
||
EmulateInstruction::Context context = { EmulateInstruction::eContextRelativeBranchImmediate, 0, 0, 0};
|
||
const uint32_t pc = ReadRegisterUnsigned(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
|
||
addr_t target; // target address
|
||
uint32_t imm32; // PC-relative offset to branch forward
|
||
bool nonzero;
|
||
switch (encoding) {
|
||
case eEncodingT1:
|
||
imm32 = Bits32(opcode, 9, 9) << 6 | Bits32(opcode, 7, 3) << 1;
|
||
nonzero = BitIsSet(opcode, 11);
|
||
target = pc + 4 + imm32;
|
||
context.arg1 = 4 + imm32; // signed offset
|
||
context.arg2 = eModeThumb; // target instruction set
|
||
break;
|
||
default:
|
||
return false;
|
||
}
|
||
if (nonzero ^ (reg_val == 0))
|
||
if (!BranchWritePC(context, target))
|
||
return false;
|
||
|
||
return true;
|
||
}
|
||
|
||
// LDM loads multiple registers from consecutive memory locations, using an
|
||
// address from a base register. Optionally the addres just above the highest of those locations
|
||
// can be written back to the base register.
|
||
bool
|
||
EmulateInstructionARM::EmulateLDM (ARMEncoding encoding)
|
||
{
|
||
#if 0
|
||
// ARM pseudo code...
|
||
if ConditionPassed()
|
||
EncodingSpecificOperations(); NullCheckIfThumbEE (n);
|
||
address = R[n];
|
||
|
||
for i = 0 to 14
|
||
if registers<i> == '1' then
|
||
R[i] = MemA[address, 4]; address = address + 4;
|
||
if registers<15> == '1' then
|
||
LoadWritePC (MemA[address, 4]);
|
||
|
||
if wback && registers<n> == '0' then R[n] = R[n] + 4 * BitCount (registers);
|
||
if wback && registers<n> == '1' then R[n] = bits(32) UNKNOWN; // Only possible for encoding A1
|
||
|
||
#endif
|
||
|
||
bool success = false;
|
||
const uint32_t opcode = OpcodeAsUnsigned (&success);
|
||
if (!success)
|
||
return false;
|
||
|
||
if (ConditionPassed())
|
||
{
|
||
uint32_t n;
|
||
uint32_t registers = 0;
|
||
bool wback;
|
||
const uint32_t addr_byte_size = GetAddressByteSize();
|
||
switch (encoding)
|
||
{
|
||
case eEncodingT1:
|
||
n = Bits32 (opcode, 10, 8);
|
||
registers = Bits32 (opcode, 7, 0);
|
||
wback = BitIsClear (registers, n);
|
||
// if BitCount(registers) < 1 then UNPREDICTABLE;
|
||
if (BitCount(registers) < 1)
|
||
return false;
|
||
break;
|
||
case eEncodingT2:
|
||
n = Bits32 (opcode, 19, 16);
|
||
registers = Bits32 (opcode, 15, 0);
|
||
wback = BitIsSet (opcode, 21);
|
||
if ((n == 15)
|
||
|| (BitCount (registers) < 2)
|
||
|| (BitIsSet (opcode, 14) && BitIsSet (opcode, 15)))
|
||
return false;
|
||
if (BitIsSet (registers, 15)
|
||
&& m_it_session.InITBlock()
|
||
&& !m_it_session.LastInITBlock())
|
||
return false;
|
||
if (wback
|
||
&& BitIsSet (registers, n))
|
||
return false;
|
||
break;
|
||
case eEncodingA1:
|
||
n = Bits32 (opcode, 19, 16);
|
||
registers = Bits32 (opcode, 15, 0);
|
||
wback = BitIsSet (opcode, 21);
|
||
if ((n == 15)
|
||
|| (BitCount (registers) < 1))
|
||
return false;
|
||
break;
|
||
default:
|
||
return false;
|
||
}
|
||
|
||
int32_t offset = 0;
|
||
const addr_t base_address = ReadRegisterUnsigned (eRegisterKindDWARF, dwarf_r0 + n, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
|
||
EmulateInstruction::Context context = { EmulateInstruction::eContextRegisterPlusOffset,
|
||
eRegisterKindDWARF,
|
||
dwarf_r0 + n,
|
||
offset };
|
||
|
||
for (int i = 0; i < 14; ++i)
|
||
{
|
||
if (BitIsSet (registers, i))
|
||
{
|
||
context.type = EmulateInstruction::eContextRegisterPlusOffset;
|
||
context.arg2 = offset;
|
||
if (wback && (n == 13)) // Pop Instruction
|
||
context.type = EmulateInstruction::eContextPopRegisterOffStack;
|
||
|
||
// R[i] = MemA [address, 4]; address = address + 4;
|
||
uint32_t data = ReadMemoryUnsigned (context, base_address + offset, addr_byte_size, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
|
||
if (!WriteRegisterUnsigned (context, eRegisterKindDWARF, dwarf_r0 + i, data))
|
||
return false;
|
||
|
||
offset += addr_byte_size;
|
||
}
|
||
}
|
||
|
||
if (BitIsSet (registers, 15))
|
||
{
|
||
//LoadWritePC (MemA [address, 4]);
|
||
context.type = EmulateInstruction::eContextRegisterPlusOffset;
|
||
context.arg2 = offset;
|
||
uint32_t data = ReadMemoryUnsigned (context, base_address + offset, addr_byte_size, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
if (!WriteRegisterUnsigned (context, eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC, data))
|
||
return false;
|
||
}
|
||
|
||
if (wback && BitIsClear (registers, n))
|
||
{
|
||
addr_t offset = addr_byte_size * BitCount (registers);
|
||
context.type = EmulateInstruction::eContextRegisterPlusOffset;
|
||
context.arg2 = offset;
|
||
|
||
// R[n] = R[n] + 4 * BitCount (registers)
|
||
if (!WriteRegisterUnsigned (context, eRegisterKindDWARF, dwarf_r0 + n, base_address + offset))
|
||
return false;
|
||
}
|
||
if (wback && BitIsSet (registers, n))
|
||
// R[n] bits(32) UNKNOWN;
|
||
return false; //I'm not convinced this is the right thing to do here...
|
||
}
|
||
return true;
|
||
}
|
||
|
||
bool
|
||
EmulateInstructionARM::EmulateLDMDB (ARMEncoding encoding)
|
||
{
|
||
#if 0
|
||
// ARM pseudo code...
|
||
if ConditionPassed() then
|
||
EncodingSpecificOperations(); NullCheckIfThumbEE(n);
|
||
address = R[n] - 4*BitCount(registers);
|
||
|
||
for i = 0 to 14
|
||
if registers<i> == ’1’ then
|
||
R[i] = MemA[address,4]; address = address + 4;
|
||
if registers<15> == ’1’ then
|
||
LoadWritePC(MemA[address,4]);
|
||
|
||
if wback && registers<n> == ’0’ then R[n] = R[n] - 4*BitCount(registers);
|
||
if wback && registers<n> == ’1’ then R[n] = bits(32) UNKNOWN; // Only possible for encoding A1
|
||
#endif
|
||
|
||
bool success = false;
|
||
const uint32_t opcode = OpcodeAsUnsigned (&success);
|
||
if (!success)
|
||
return false;
|
||
|
||
if (ConditionPassed())
|
||
{
|
||
uint32_t n;
|
||
uint32_t registers = 0;
|
||
bool wback;
|
||
const uint32_t addr_byte_size = GetAddressByteSize();
|
||
switch (encoding)
|
||
{
|
||
case eEncodingT1:
|
||
// n = UInt(Rn); registers = P:M:’0’:register_list; wback = (W == ’1’);
|
||
n = Bits32 (opcode, 19, 16);
|
||
registers = Bits32 (opcode, 15, 0);
|
||
wback = BitIsSet (opcode, 21);
|
||
|
||
// if n == 15 || BitCount(registers) < 2 || (P == ’1’ && M == ’1’) then UNPREDICTABLE;
|
||
if ((n == 15)
|
||
|| (BitCount (registers) < 2)
|
||
|| (BitIsSet (opcode, 14) && BitIsSet (opcode, 15)))
|
||
return false;
|
||
|
||
// if registers<15> == ’1’ && InITBlock() && !LastInITBlock() then UNPREDICTABLE;
|
||
if (BitIsSet (registers, 15)
|
||
&& m_it_session.InITBlock()
|
||
&& !m_it_session.LastInITBlock())
|
||
return false;
|
||
|
||
// if wback && registers<n> == ’1’ then UNPREDICTABLE;
|
||
if (wback && BitIsSet (registers, n))
|
||
return false;
|
||
|
||
break;
|
||
|
||
case eEncodingA1:
|
||
// n = UInt(Rn); registers = register_list; wback = (W == ’1’);
|
||
n = Bits32 (opcode, 19, 16);
|
||
registers = Bits32 (opcode, 15, 0);
|
||
wback = BitIsSet (opcode, 21);
|
||
|
||
// if n == 15 || BitCount(registers) < 1 then UNPREDICTABLE;
|
||
if ((n == 15) || (BitCount (registers) < 1))
|
||
return false;
|
||
|
||
break;
|
||
|
||
default:
|
||
return false;
|
||
}
|
||
|
||
int32_t offset = 0;
|
||
addr_t address = ReadRegisterUnsigned (eRegisterKindDWARF, dwarf_r0 + n, 0, &success)
|
||
- (addr_byte_size * BitCount (registers));
|
||
EmulateInstruction::Context context = { EmulateInstruction::eContextRegisterPlusOffset,
|
||
eRegisterKindDWARF,
|
||
dwarf_r0 + n,
|
||
offset };
|
||
|
||
for (int i = 0; i < 14; ++i)
|
||
{
|
||
if (BitIsSet (registers, i))
|
||
{
|
||
// R[i] = MemA[address,4]; address = address + 4;
|
||
context.arg2 = offset;
|
||
uint32_t data = ReadMemoryUnsigned (context, address + offset, addr_byte_size, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
|
||
if (!WriteRegisterUnsigned (context, eRegisterKindDWARF, dwarf_r0 + i, data))
|
||
return false;
|
||
|
||
offset += addr_byte_size;
|
||
}
|
||
}
|
||
|
||
// if registers<15> == ’1’ then
|
||
// LoadWritePC(MemA[address,4]);
|
||
if (BitIsSet (registers, 15))
|
||
{
|
||
context.arg2 = offset;
|
||
uint32_t data = ReadMemoryUnsigned (context, address + offset, addr_byte_size, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
if (!WriteRegisterUnsigned (context, eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC, data))
|
||
return false;
|
||
}
|
||
|
||
// if wback && registers<n> == ’0’ then R[n] = R[n] - 4*BitCount(registers);
|
||
if (wback && BitIsClear (registers, n))
|
||
{
|
||
context.arg2 = offset;
|
||
addr_t addr = ReadRegisterUnsigned (eRegisterKindDWARF, dwarf_r0 + n, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
addr = addr - (addr_byte_size * BitCount (registers));
|
||
if (!WriteRegisterUnsigned (context, eRegisterKindDWARF, dwarf_r0 + n, addr))
|
||
return false;
|
||
}
|
||
|
||
// if wback && registers<n> == ’1’ then R[n] = bits(32) UNKNOWN; // Only possible for encoding A1
|
||
if (wback && BitIsSet (registers, n))
|
||
return false; // I'm not sure this is right; how do I set R[n] to bits(32) UNKNOWN.
|
||
}
|
||
return true;
|
||
}
|
||
|
||
bool
|
||
EmulateInstructionARM::EmulateLDMIB (ARMEncoding encoding)
|
||
{
|
||
#if 0
|
||
if ConditionPassed() then
|
||
EncodingSpecificOperations();
|
||
address = R[n] + 4;
|
||
|
||
for i = 0 to 14
|
||
if registers<i> == ’1’ then
|
||
R[i] = MemA[address,4]; address = address + 4;
|
||
if registers<15> == ’1’ then
|
||
LoadWritePC(MemA[address,4]);
|
||
|
||
if wback && registers<n> == ’0’ then R[n] = R[n] + 4*BitCount(registers);
|
||
if wback && registers<n> == ’1’ then R[n] = bits(32) UNKNOWN;
|
||
#endif
|
||
|
||
bool success = false;
|
||
const uint32_t opcode = OpcodeAsUnsigned (&success);
|
||
if (!success)
|
||
return false;
|
||
|
||
if (ConditionPassed())
|
||
{
|
||
uint32_t n;
|
||
uint32_t registers = 0;
|
||
bool wback;
|
||
const uint32_t addr_byte_size = GetAddressByteSize();
|
||
switch (encoding)
|
||
{
|
||
case eEncodingA1:
|
||
// n = UInt(Rn); registers = register_list; wback = (W == ’1’);
|
||
n = Bits32 (opcode, 19, 16);
|
||
registers = Bits32 (opcode, 15, 0);
|
||
wback = BitIsSet (opcode, 21);
|
||
|
||
// if n == 15 || BitCount(registers) < 1 then UNPREDICTABLE;
|
||
if ((n == 15) || (BitCount (registers) < 1))
|
||
return false;
|
||
|
||
break;
|
||
default:
|
||
return false;
|
||
}
|
||
// address = R[n] + 4;
|
||
|
||
int32_t offset = 0;
|
||
addr_t address = ReadRegisterUnsigned (eRegisterKindDWARF, dwarf_r0 + n, 0, &success) + addr_byte_size;
|
||
|
||
EmulateInstruction::Context context = { EmulateInstruction::eContextRegisterPlusOffset,
|
||
eRegisterKindDWARF,
|
||
dwarf_r0 + n,
|
||
offset };
|
||
|
||
for (int i = 0; i < 14; ++i)
|
||
{
|
||
if (BitIsSet (registers, i))
|
||
{
|
||
// R[i] = MemA[address,4]; address = address + 4;
|
||
|
||
context.arg2 = offset;
|
||
uint32_t data = ReadMemoryUnsigned (context, address + offset, addr_byte_size, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
|
||
if (!WriteRegisterUnsigned (context, eRegisterKindDWARF, dwarf_r0 + i, data))
|
||
return false;
|
||
|
||
offset += addr_byte_size;
|
||
}
|
||
}
|
||
|
||
// if registers<15> == ’1’ then
|
||
// LoadWritePC(MemA[address,4]);
|
||
if (BitIsSet (registers, 15))
|
||
{
|
||
context.arg2 = offset;
|
||
uint32_t data = ReadMemoryUnsigned (context, address + offset, addr_byte_size, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
if (!WriteRegisterUnsigned (context, eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC, data))
|
||
return false;
|
||
}
|
||
|
||
// if wback && registers<n> == ’0’ then R[n] = R[n] + 4*BitCount(registers);
|
||
if (wback && BitIsClear (registers, n))
|
||
{
|
||
context.arg2 = offset;
|
||
addr_t addr = ReadRegisterUnsigned (eRegisterKindDWARF, dwarf_r0 + n, 0, &success);
|
||
if (!success)
|
||
return false;
|
||
addr = addr + (addr_byte_size * BitCount (registers));
|
||
if (!WriteRegisterUnsigned (context, eRegisterKindDWARF, dwarf_r0 + n, addr))
|
||
return false;
|
||
}
|
||
|
||
// if wback && registers<n> == ’1’ then R[n] = bits(32) UNKNOWN; // Only possible for encoding A1
|
||
if (wback && BitIsSet (registers, n))
|
||
return false; // I'm not sure this is right; how do I set R[n] to bits(32) UNKNOWN.
|
||
}
|
||
return true;
|
||
}
|
||
|
||
EmulateInstructionARM::ARMOpcode*
|
||
EmulateInstructionARM::GetARMOpcodeForInstruction (const uint32_t opcode)
|
||
{
|
||
static ARMOpcode
|
||
g_arm_opcodes[] =
|
||
{
|
||
//----------------------------------------------------------------------
|
||
// Prologue instructions
|
||
//----------------------------------------------------------------------
|
||
|
||
// push register(s)
|
||
{ 0x0fff0000, 0x092d0000, ARMvAll, eEncodingA1, eSize32, &EmulateInstructionARM::EmulatePush, "push <registers>" },
|
||
{ 0x0fff0fff, 0x052d0004, ARMvAll, eEncodingA2, eSize32, &EmulateInstructionARM::EmulatePush, "push <register>" },
|
||
|
||
// set r7 to point to a stack offset
|
||
{ 0x0ffff000, 0x028d7000, ARMvAll, eEncodingA1, eSize32, &EmulateInstructionARM::EmulateAddRdSPImmediate, "add r7, sp, #<const>" },
|
||
{ 0x0ffff000, 0x024c7000, ARMvAll, eEncodingA1, eSize32, &EmulateInstructionARM::EmulateSubR7IPImmediate, "sub r7, ip, #<const>"},
|
||
// set ip to point to a stack offset
|
||
{ 0x0fffffff, 0x01a0c00d, ARMvAll, eEncodingA1, eSize32, &EmulateInstructionARM::EmulateMovRdSP, "mov ip, sp" },
|
||
{ 0x0ffff000, 0x028dc000, ARMvAll, eEncodingA1, eSize32, &EmulateInstructionARM::EmulateAddRdSPImmediate, "add ip, sp, #<const>" },
|
||
{ 0x0ffff000, 0x024dc000, ARMvAll, eEncodingA1, eSize32, &EmulateInstructionARM::EmulateSubIPSPImmediate, "sub ip, sp, #<const>"},
|
||
|
||
// adjust the stack pointer
|
||
{ 0x0ffff000, 0x024dd000, ARMvAll, eEncodingA1, eSize32, &EmulateInstructionARM::EmulateSubSPImmdiate, "sub sp, sp, #<const>"},
|
||
|
||
// push one register
|
||
// if Rn == '1101' && imm12 == '000000000100' then SEE PUSH;
|
||
{ 0x0fff0000, 0x052d0000, ARMvAll, eEncodingA1, eSize32, &EmulateInstructionARM::EmulateSTRRtSP, "str Rt, [sp, #-imm12]!" },
|
||
|
||
// vector push consecutive extension register(s)
|
||
{ 0x0fbf0f00, 0x0d2d0b00, ARMV6T2_ABOVE, eEncodingA1, eSize32, &EmulateInstructionARM::EmulateVPUSH, "vpush.64 <list>"},
|
||
{ 0x0fbf0f00, 0x0d2d0a00, ARMV6T2_ABOVE, eEncodingA2, eSize32, &EmulateInstructionARM::EmulateVPUSH, "vpush.32 <list>"},
|
||
|
||
//----------------------------------------------------------------------
|
||
// Epilogue instructions
|
||
//----------------------------------------------------------------------
|
||
|
||
// To resolve ambiguity, "blx <label>" should come before "bl <label>".
|
||
{ 0xfe000000, 0xfa000000, ARMV5_ABOVE, eEncodingA2, eSize32, &EmulateInstructionARM::EmulateBLXImmediate, "blx <label>"},
|
||
{ 0x0f000000, 0x0b000000, ARMvAll, eEncodingA1, eSize32, &EmulateInstructionARM::EmulateBLXImmediate, "bl <label>"},
|
||
{ 0x0ffffff0, 0x012fff30, ARMV5_ABOVE, eEncodingA1, eSize32, &EmulateInstructionARM::EmulateBLXRm, "blx <Rm>"},
|
||
{ 0x0fff0000, 0x08bd0000, ARMvAll, eEncodingA1, eSize32, &EmulateInstructionARM::EmulatePop, "pop <registers>"},
|
||
{ 0x0fff0fff, 0x049d0004, ARMvAll, eEncodingA2, eSize32, &EmulateInstructionARM::EmulatePop, "pop <register>"},
|
||
{ 0x0fbf0f00, 0x0cbd0b00, ARMV6T2_ABOVE, eEncodingA1, eSize32, &EmulateInstructionARM::EmulateVPOP, "vpop.64 <list>"},
|
||
{ 0x0fbf0f00, 0x0cbd0a00, ARMV6T2_ABOVE, eEncodingA2, eSize32, &EmulateInstructionARM::EmulateVPOP, "vpop.32 <list>"},
|
||
|
||
//----------------------------------------------------------------------
|
||
// Supervisor Call (previously Software Interrupt)
|
||
//----------------------------------------------------------------------
|
||
{ 0x0f000000, 0x0f000000, ARMvAll, eEncodingA1, eSize32, &EmulateInstructionARM::EmulateSVC, "svc #imm24"},
|
||
|
||
//----------------------------------------------------------------------
|
||
// Branch instructions
|
||
//----------------------------------------------------------------------
|
||
{ 0x0f000000, 0x0a000000, ARMvAll, eEncodingA1, eSize32, &EmulateInstructionARM::EmulateSVC, "b #imm24"},
|
||
|
||
//----------------------------------------------------------------------
|
||
// Load instructions
|
||
//----------------------------------------------------------------------
|
||
{ 0x0fd00000, 0x08900000, ARMvAll, eEncodingA1, eSize32, &EmulateInstructionARM::EmulateLDM, "ldm<c> <Rn>{!} <registers>" },
|
||
{ 0x0fd00000, 0x09100000, ARMvAll, eEncodingA1, eSize32, &EmulateInstructionARM::EmulateLDMDB, "ldmdb<c> <Rn>{!} <registers>" },
|
||
{ 0x0fd00000, 0x09900000, ARMvAll, eEncodingA1, eSize32, &EmulateInstructionARM::EmulateLDMIB, "ldmib<c> <Rn<{!} <registers>" }
|
||
|
||
};
|
||
static const size_t k_num_arm_opcodes = sizeof(g_arm_opcodes)/sizeof(ARMOpcode);
|
||
|
||
for (size_t i=0; i<k_num_arm_opcodes; ++i)
|
||
{
|
||
if ((g_arm_opcodes[i].mask & opcode) == g_arm_opcodes[i].value)
|
||
return &g_arm_opcodes[i];
|
||
}
|
||
return NULL;
|
||
}
|
||
|
||
|
||
EmulateInstructionARM::ARMOpcode*
|
||
EmulateInstructionARM::GetThumbOpcodeForInstruction (const uint32_t opcode)
|
||
{
|
||
|
||
static ARMOpcode
|
||
g_thumb_opcodes[] =
|
||
{
|
||
//----------------------------------------------------------------------
|
||
// Prologue instructions
|
||
//----------------------------------------------------------------------
|
||
|
||
// push register(s)
|
||
{ 0xfffffe00, 0x0000b400, ARMvAll, eEncodingT1, eSize16, &EmulateInstructionARM::EmulatePush, "push <registers>" },
|
||
{ 0xffff0000, 0xe92d0000, ARMV6T2_ABOVE, eEncodingT2, eSize32, &EmulateInstructionARM::EmulatePush, "push.w <registers>" },
|
||
{ 0xffff0fff, 0xf84d0d04, ARMV6T2_ABOVE, eEncodingT3, eSize32, &EmulateInstructionARM::EmulatePush, "push.w <register>" },
|
||
// move from high register to low register
|
||
{ 0xffffffc0, 0x00004640, ARMvAll, eEncodingT1, eSize16, &EmulateInstructionARM::EmulateMovLowHigh, "mov r0-r7, r8-r15" },
|
||
|
||
// set r7 to point to a stack offset
|
||
{ 0xffffff00, 0x0000af00, ARMvAll, eEncodingT1, eSize16, &EmulateInstructionARM::EmulateAddRdSPImmediate, "add r7, sp, #imm" },
|
||
{ 0xffffffff, 0x0000466f, ARMvAll, eEncodingT1, eSize16, &EmulateInstructionARM::EmulateMovRdSP, "mov r7, sp" },
|
||
|
||
// PC relative load into register (see also EmulateAddSPRm)
|
||
{ 0xfffff800, 0x00004800, ARMvAll, eEncodingT1, eSize16, &EmulateInstructionARM::EmulateLDRRdPCRelative, "ldr <Rd>, [PC, #imm]"},
|
||
|
||
// adjust the stack pointer
|
||
{ 0xffffff87, 0x00004485, ARMvAll, eEncodingT2, eSize16, &EmulateInstructionARM::EmulateAddSPRm, "add sp, <Rm>"},
|
||
{ 0xffffff80, 0x0000b080, ARMvAll, eEncodingT1, eSize16, &EmulateInstructionARM::EmulateSubSPImmdiate, "add sp, sp, #imm"},
|
||
{ 0xfbef8f00, 0xf1ad0d00, ARMV6T2_ABOVE, eEncodingT2, eSize32, &EmulateInstructionARM::EmulateSubSPImmdiate, "sub.w sp, sp, #<const>"},
|
||
{ 0xfbff8f00, 0xf2ad0d00, ARMV6T2_ABOVE, eEncodingT3, eSize32, &EmulateInstructionARM::EmulateSubSPImmdiate, "subw sp, sp, #imm12"},
|
||
|
||
// vector push consecutive extension register(s)
|
||
{ 0xffbf0f00, 0xed2d0b00, ARMV6T2_ABOVE, eEncodingT1, eSize32, &EmulateInstructionARM::EmulateVPUSH, "vpush.64 <list>"},
|
||
{ 0xffbf0f00, 0xed2d0a00, ARMV6T2_ABOVE, eEncodingT2, eSize32, &EmulateInstructionARM::EmulateVPUSH, "vpush.32 <list>"},
|
||
|
||
//----------------------------------------------------------------------
|
||
// Epilogue instructions
|
||
//----------------------------------------------------------------------
|
||
|
||
{ 0xffffff80, 0x0000b000, ARMvAll, eEncodingT2, eSize16, &EmulateInstructionARM::EmulateAddSPImmediate, "add sp, #imm"},
|
||
{ 0xffffff87, 0x00004780, ARMV5_ABOVE, eEncodingT1, eSize16, &EmulateInstructionARM::EmulateBLXRm, "blx <Rm>"},
|
||
// J1 == J2 == 1
|
||
{ 0xf800f800, 0xf000f800, ARMV4T_ABOVE, eEncodingT1, eSize32, &EmulateInstructionARM::EmulateBLXImmediate, "bl <label>"},
|
||
// J1 == J2 == 1
|
||
{ 0xf800e800, 0xf000e800, ARMV5_ABOVE, eEncodingT2, eSize32, &EmulateInstructionARM::EmulateBLXImmediate, "blx <label>"},
|
||
{ 0xfffffe00, 0x0000bc00, ARMvAll, eEncodingT1, eSize16, &EmulateInstructionARM::EmulatePop, "pop <registers>"},
|
||
{ 0xffff0000, 0xe8bd0000, ARMV6T2_ABOVE, eEncodingT2, eSize32, &EmulateInstructionARM::EmulatePop, "pop.w <registers>" },
|
||
{ 0xffff0fff, 0xf85d0d04, ARMV6T2_ABOVE, eEncodingT3, eSize32, &EmulateInstructionARM::EmulatePop, "pop.w <register>" },
|
||
{ 0xffbf0f00, 0xecbd0b00, ARMV6T2_ABOVE, eEncodingT1, eSize32, &EmulateInstructionARM::EmulateVPOP, "vpop.64 <list>"},
|
||
{ 0xffbf0f00, 0xecbd0a00, ARMV6T2_ABOVE, eEncodingT2, eSize32, &EmulateInstructionARM::EmulateVPOP, "vpop.32 <list>"},
|
||
|
||
//----------------------------------------------------------------------
|
||
// Supervisor Call (previously Software Interrupt)
|
||
//----------------------------------------------------------------------
|
||
{ 0xffffff00, 0x0000df00, ARMvAll, eEncodingT1, eSize16, &EmulateInstructionARM::EmulateSVC, "svc #imm8"},
|
||
|
||
//----------------------------------------------------------------------
|
||
// If Then makes up to four following instructions conditional.
|
||
//----------------------------------------------------------------------
|
||
{ 0xffffff00, 0x0000bf00, ARMvAll, eEncodingT1, eSize16, &EmulateInstructionARM::EmulateIT, "it{<x>{<y>{<z>}}} <firstcond>"},
|
||
|
||
//----------------------------------------------------------------------
|
||
// Branch instructions
|
||
//----------------------------------------------------------------------
|
||
// To resolve ambiguity, "b<c> #imm8" should come after "svc #imm8".
|
||
{ 0xfffff000, 0x0000d000, ARMvAll, eEncodingT1, eSize16, &EmulateInstructionARM::EmulateB, "b<c> #imm8 (outside IT)"},
|
||
{ 0xffff8000, 0x0000e000, ARMvAll, eEncodingT2, eSize16, &EmulateInstructionARM::EmulateB, "b #imm11 (outside or last in IT)"},
|
||
{ 0xf800d000, 0xf0008000, ARMV6T2_ABOVE, eEncodingT3, eSize32, &EmulateInstructionARM::EmulateB, "b<c>.w #imm8 (outside IT)"},
|
||
{ 0xf800d000, 0xf0009000, ARMV6T2_ABOVE, eEncodingT4, eSize32, &EmulateInstructionARM::EmulateB, "b.w #imm8 (outside or last in IT)"},
|
||
// compare and branch
|
||
{ 0xfffff500, 0x0000b100, ARMV6T2_ABOVE, eEncodingT1, eSize16, &EmulateInstructionARM::EmulateCB, "cb{n}z <Rn>, <label>"},
|
||
|
||
//----------------------------------------------------------------------
|
||
// Load instructions
|
||
//----------------------------------------------------------------------
|
||
{ 0xfffff800, 0x0000c800, ARMV4T_ABOVE, eEncodingT1, eSize16, &EmulateInstructionARM::EmulateLDM, "ldm<c> <Rn>{!} <registers>" },
|
||
{ 0xffd02000, 0xe8900000, ARMV6T2_ABOVE, eEncodingT2, eSize32, &EmulateInstructionARM::EmulateLDM, "ldm<c>.w <Rn>{!} <registers>" },
|
||
{ 0xffd00000, 0xe9100000, ARMV6T2_ABOVE, eEncodingT1, eSize32, &EmulateInstructionARM::EmulateLDMDB, "ldmdb<c> <Rn>{!} <registers>" }
|
||
|
||
};
|
||
|
||
const size_t k_num_thumb_opcodes = sizeof(g_thumb_opcodes)/sizeof(ARMOpcode);
|
||
for (size_t i=0; i<k_num_thumb_opcodes; ++i)
|
||
{
|
||
if ((g_thumb_opcodes[i].mask & opcode) == g_thumb_opcodes[i].value)
|
||
return &g_thumb_opcodes[i];
|
||
}
|
||
return NULL;
|
||
}
|
||
|
||
bool
|
||
EmulateInstructionARM::SetTargetTriple (const ConstString &triple)
|
||
{
|
||
m_arm_isa = 0;
|
||
const char *triple_cstr = triple.GetCString();
|
||
if (triple_cstr)
|
||
{
|
||
const char *dash = ::strchr (triple_cstr, '-');
|
||
if (dash)
|
||
{
|
||
std::string arch (triple_cstr, dash);
|
||
const char *arch_cstr = arch.c_str();
|
||
if (strcasecmp(arch_cstr, "armv4t") == 0)
|
||
m_arm_isa = ARMv4T;
|
||
else if (strcasecmp(arch_cstr, "armv4") == 0)
|
||
m_arm_isa = ARMv4;
|
||
else if (strcasecmp(arch_cstr, "armv5tej") == 0)
|
||
m_arm_isa = ARMv5TEJ;
|
||
else if (strcasecmp(arch_cstr, "armv5te") == 0)
|
||
m_arm_isa = ARMv5TE;
|
||
else if (strcasecmp(arch_cstr, "armv5t") == 0)
|
||
m_arm_isa = ARMv5T;
|
||
else if (strcasecmp(arch_cstr, "armv6k") == 0)
|
||
m_arm_isa = ARMv6K;
|
||
else if (strcasecmp(arch_cstr, "armv6") == 0)
|
||
m_arm_isa = ARMv6;
|
||
else if (strcasecmp(arch_cstr, "armv6t2") == 0)
|
||
m_arm_isa = ARMv6T2;
|
||
else if (strcasecmp(arch_cstr, "armv7") == 0)
|
||
m_arm_isa = ARMv7;
|
||
else if (strcasecmp(arch_cstr, "armv8") == 0)
|
||
m_arm_isa = ARMv8;
|
||
}
|
||
}
|
||
return m_arm_isa != 0;
|
||
}
|
||
|
||
|
||
bool
|
||
EmulateInstructionARM::ReadInstruction ()
|
||
{
|
||
bool success = false;
|
||
m_inst_cpsr = ReadRegisterUnsigned (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_FLAGS, 0, &success);
|
||
if (success)
|
||
{
|
||
addr_t pc = ReadRegisterUnsigned (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC, LLDB_INVALID_ADDRESS, &success);
|
||
if (success)
|
||
{
|
||
Context read_inst_context = {eContextReadOpcode, 0, 0};
|
||
if (m_inst_cpsr & MASK_CPSR_T)
|
||
{
|
||
m_inst_mode = eModeThumb;
|
||
uint32_t thumb_opcode = ReadMemoryUnsigned(read_inst_context, pc, 2, 0, &success);
|
||
|
||
if (success)
|
||
{
|
||
if ((m_inst.opcode.inst16 & 0xe000) != 0xe000 || ((m_inst.opcode.inst16 & 0x1800u) == 0))
|
||
{
|
||
m_inst.opcode_type = eOpcode16;
|
||
m_inst.opcode.inst16 = thumb_opcode;
|
||
}
|
||
else
|
||
{
|
||
m_inst.opcode_type = eOpcode32;
|
||
m_inst.opcode.inst32 = (thumb_opcode << 16) | ReadMemoryUnsigned(read_inst_context, pc + 2, 2, 0, &success);
|
||
}
|
||
}
|
||
}
|
||
else
|
||
{
|
||
m_inst_mode = eModeARM;
|
||
m_inst.opcode_type = eOpcode32;
|
||
m_inst.opcode.inst32 = ReadMemoryUnsigned(read_inst_context, pc, 4, 0, &success);
|
||
}
|
||
}
|
||
}
|
||
if (!success)
|
||
{
|
||
m_inst_mode = eModeInvalid;
|
||
m_inst_pc = LLDB_INVALID_ADDRESS;
|
||
}
|
||
return success;
|
||
}
|
||
|
||
uint32_t
|
||
EmulateInstructionARM::ArchVersion ()
|
||
{
|
||
return m_arm_isa;
|
||
}
|
||
|
||
bool
|
||
EmulateInstructionARM::ConditionPassed ()
|
||
{
|
||
if (m_inst_cpsr == 0)
|
||
return false;
|
||
|
||
const uint32_t cond = CurrentCond ();
|
||
|
||
if (cond == UINT32_MAX)
|
||
return false;
|
||
|
||
bool result = false;
|
||
switch (UnsignedBits(cond, 3, 1))
|
||
{
|
||
case 0: result = (m_inst_cpsr & MASK_CPSR_Z) != 0; break;
|
||
case 1: result = (m_inst_cpsr & MASK_CPSR_C) != 0; break;
|
||
case 2: result = (m_inst_cpsr & MASK_CPSR_N) != 0; break;
|
||
case 3: result = (m_inst_cpsr & MASK_CPSR_V) != 0; break;
|
||
case 4: result = ((m_inst_cpsr & MASK_CPSR_C) != 0) && ((m_inst_cpsr & MASK_CPSR_Z) == 0); break;
|
||
case 5:
|
||
{
|
||
bool n = (m_inst_cpsr & MASK_CPSR_N);
|
||
bool v = (m_inst_cpsr & MASK_CPSR_V);
|
||
result = n == v;
|
||
}
|
||
break;
|
||
case 6:
|
||
{
|
||
bool n = (m_inst_cpsr & MASK_CPSR_N);
|
||
bool v = (m_inst_cpsr & MASK_CPSR_V);
|
||
result = n == v && ((m_inst_cpsr & MASK_CPSR_Z) == 0);
|
||
}
|
||
break;
|
||
case 7:
|
||
result = true;
|
||
break;
|
||
}
|
||
|
||
if (cond & 1)
|
||
result = !result;
|
||
return result;
|
||
}
|
||
|
||
uint32_t
|
||
EmulateInstructionARM::CurrentCond ()
|
||
{
|
||
switch (m_inst_mode)
|
||
{
|
||
default:
|
||
case eModeInvalid:
|
||
break;
|
||
|
||
case eModeARM:
|
||
return UnsignedBits(m_inst.opcode.inst32, 31, 28);
|
||
|
||
case eModeThumb:
|
||
// For T1 and T3 encodings of the Branch instruction, it returns the 4-bit
|
||
// 'cond' field of the encoding.
|
||
if (m_inst.opcode_type == eOpcode16 &&
|
||
Bits32(m_inst.opcode.inst16, 15, 12) == 0x0d &&
|
||
Bits32(m_inst.opcode.inst16, 11, 7) != 0x0f)
|
||
{
|
||
return Bits32(m_inst.opcode.inst16, 11, 7);
|
||
}
|
||
else if (m_inst.opcode_type == eOpcode32 &&
|
||
Bits32(m_inst.opcode.inst32, 31, 27) == 0x1e &&
|
||
Bits32(m_inst.opcode.inst32, 15, 14) == 0x02 &&
|
||
Bits32(m_inst.opcode.inst32, 12, 12) == 0x00 &&
|
||
Bits32(m_inst.opcode.inst32, 25, 22) <= 0x0d)
|
||
{
|
||
return Bits32(m_inst.opcode.inst32, 25, 22);
|
||
}
|
||
|
||
return m_it_session.GetCond();
|
||
}
|
||
return UINT32_MAX; // Return invalid value
|
||
}
|
||
|
||
bool
|
||
EmulateInstructionARM::BranchWritePC (const Context &context, uint32_t addr)
|
||
{
|
||
addr_t target;
|
||
|
||
// Check the current instruction set.
|
||
if (CurrentInstrSet() == eModeARM)
|
||
target = addr & 0xfffffffc;
|
||
else
|
||
target = addr & 0xfffffffe;
|
||
|
||
if (!WriteRegisterUnsigned (context, eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC, target))
|
||
return false;
|
||
|
||
return true;
|
||
}
|
||
|
||
// As a side effect, BXWritePC sets context.arg2 to eModeARM or eModeThumb by inspecting addr.
|
||
bool
|
||
EmulateInstructionARM::BXWritePC (Context &context, uint32_t addr)
|
||
{
|
||
addr_t target;
|
||
|
||
if (BitIsSet(addr, 0))
|
||
{
|
||
SelectInstrSet(eModeThumb);
|
||
target = addr & 0xfffffffe;
|
||
context.arg2 = eModeThumb;
|
||
}
|
||
else if (BitIsClear(addr, 1))
|
||
{
|
||
SelectInstrSet(eModeARM);
|
||
target = addr & 0xfffffffc;
|
||
context.arg2 = eModeARM;
|
||
}
|
||
else
|
||
return false; // address<1:0> == '10' => UNPREDICTABLE
|
||
|
||
if (!WriteRegisterUnsigned (context, eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC, target))
|
||
return false;
|
||
|
||
return true;
|
||
}
|
||
|
||
// Dispatches to either BXWritePC or BranchWritePC based on architecture versions.
|
||
bool
|
||
EmulateInstructionARM::LoadWritePC (Context &context, uint32_t addr)
|
||
{
|
||
if (ArchVersion() >= ARMv5T)
|
||
return BXWritePC(context, addr);
|
||
else
|
||
return BranchWritePC((const Context)context, addr);
|
||
}
|
||
|
||
EmulateInstructionARM::Mode
|
||
EmulateInstructionARM::CurrentInstrSet ()
|
||
{
|
||
return m_inst_mode;
|
||
}
|
||
|
||
// Set the 'T' bit of our CPSR. The m_inst_mode gets updated when the next
|
||
// ReadInstruction() is performed.
|
||
bool
|
||
EmulateInstructionARM::SelectInstrSet (Mode arm_or_thumb)
|
||
{
|
||
switch (arm_or_thumb)
|
||
{
|
||
default:
|
||
return false;
|
||
eModeARM:
|
||
// Clear the T bit.
|
||
m_inst_cpsr &= ~MASK_CPSR_T;
|
||
break;
|
||
eModeThumb:
|
||
// Set the T bit.
|
||
m_inst_cpsr |= MASK_CPSR_T;
|
||
break;
|
||
}
|
||
return true;
|
||
}
|
||
|
||
bool
|
||
EmulateInstructionARM::EvaluateInstruction ()
|
||
{
|
||
// Advance the ITSTATE bits to their values for the next instruction.
|
||
if (m_inst_mode == eModeThumb && m_it_session.InITBlock())
|
||
m_it_session.ITAdvance();
|
||
|
||
return false;
|
||
}
|