gdbstub: Update registers and sizes for aarch64

This gets gdbstub working at least to the point where clients can
communicate with it.

What works:
- Reading/writing GPRegs
- Reading/writing memory
- Interrupting the emulated program and continuing

What does NOT work:
- Breakpoints. Sizes have been updated to u64, but support will need to be
  added in the interpreter for them to work.
- VRegs. Mostly because my gdb was having issues with 128-bit regs for
  some reason. However, the current u128 representation is a bit
  awkward to use and should probably be updated first.
This commit is contained in:
Rozlette 2018-01-21 10:53:09 -06:00
parent d904b0db58
commit 425a78ec1b

View File

@ -57,9 +57,10 @@ const u32 SIGTERM = 15;
const u32 MSG_WAITALL = 8;
#endif
const u32 R15_REGISTER = 15;
const u32 CPSR_REGISTER = 25;
const u32 FPSCR_REGISTER = 58;
const u32 X30_REGISTER = 30;
const u32 SP_REGISTER = 31;
const u32 PC_REGISTER = 32;
const u32 CPSR_REGISTER = 33;
// For sample XML files see the GDB source /gdb/features
// GDB also wants the l character at the start
@ -68,48 +69,62 @@ static const char* target_xml =
R"(l<?xml version="1.0"?>
<!DOCTYPE target SYSTEM "gdb-target.dtd">
<target version="1.0">
<feature name="org.gnu.gdb.arm.core">
<reg name="r0" bitsize="32"/>
<reg name="r1" bitsize="32"/>
<reg name="r2" bitsize="32"/>
<reg name="r3" bitsize="32"/>
<reg name="r4" bitsize="32"/>
<reg name="r5" bitsize="32"/>
<reg name="r6" bitsize="32"/>
<reg name="r7" bitsize="32"/>
<reg name="r8" bitsize="32"/>
<reg name="r9" bitsize="32"/>
<reg name="r10" bitsize="32"/>
<reg name="r11" bitsize="32"/>
<reg name="r12" bitsize="32"/>
<reg name="sp" bitsize="32" type="data_ptr"/>
<reg name="lr" bitsize="32"/>
<reg name="pc" bitsize="32" type="code_ptr"/>
<feature name="org.gnu.gdb.aarch64.core">
<reg name="x0" bitsize="64"/>
<reg name="x1" bitsize="64"/>
<reg name="x2" bitsize="64"/>
<reg name="x3" bitsize="64"/>
<reg name="x4" bitsize="64"/>
<reg name="x5" bitsize="64"/>
<reg name="x6" bitsize="64"/>
<reg name="x7" bitsize="64"/>
<reg name="x8" bitsize="64"/>
<reg name="x9" bitsize="64"/>
<reg name="x10" bitsize="64"/>
<reg name="x11" bitsize="64"/>
<reg name="x12" bitsize="64"/>
<reg name="x13" bitsize="64"/>
<reg name="x14" bitsize="64"/>
<reg name="x15" bitsize="64"/>
<reg name="x16" bitsize="64"/>
<reg name="x17" bitsize="64"/>
<reg name="x18" bitsize="64"/>
<reg name="x19" bitsize="64"/>
<reg name="x20" bitsize="64"/>
<reg name="x21" bitsize="64"/>
<reg name="x22" bitsize="64"/>
<reg name="x23" bitsize="64"/>
<reg name="x24" bitsize="64"/>
<reg name="x25" bitsize="64"/>
<reg name="x26" bitsize="64"/>
<reg name="x27" bitsize="64"/>
<reg name="x28" bitsize="64"/>
<reg name="x29" bitsize="64"/>
<reg name="x30" bitsize="64"/>
<reg name="sp" bitsize="64" type="data_ptr"/>
<!-- The CPSR is register 25, rather than register 16, because
the FPA registers historically were placed between the PC
and the CPSR in the "g" packet. -->
<reg name="pc" bitsize="64" type="code_ptr"/>
<reg name="cpsr" bitsize="32" regnum="25"/>
</feature>
<feature name="org.gnu.gdb.arm.vfp">
<reg name="d0" bitsize="64" type="float"/>
<reg name="d1" bitsize="64" type="float"/>
<reg name="d2" bitsize="64" type="float"/>
<reg name="d3" bitsize="64" type="float"/>
<reg name="d4" bitsize="64" type="float"/>
<reg name="d5" bitsize="64" type="float"/>
<reg name="d6" bitsize="64" type="float"/>
<reg name="d7" bitsize="64" type="float"/>
<reg name="d8" bitsize="64" type="float"/>
<reg name="d9" bitsize="64" type="float"/>
<reg name="d10" bitsize="64" type="float"/>
<reg name="d11" bitsize="64" type="float"/>
<reg name="d12" bitsize="64" type="float"/>
<reg name="d13" bitsize="64" type="float"/>
<reg name="d14" bitsize="64" type="float"/>
<reg name="d15" bitsize="64" type="float"/>
<reg name="fpscr" bitsize="32" type="int" group="float"/>
<flags id="cpsr_flags" size="4">
<field name="SP" start="0" end="0"/>
<field name="" start="1" end="1"/>
<field name="EL" start="2" end="3"/>
<field name="nRW" start="4" end="4"/>
<field name="" start="5" end="5"/>
<field name="F" start="6" end="6"/>
<field name="I" start="7" end="7"/>
<field name="A" start="8" end="8"/>
<field name="D" start="9" end="9"/>
<field name="IL" start="20" end="20"/>
<field name="SS" start="21" end="21"/>
<field name="V" start="28" end="28"/>
<field name="C" start="29" end="29"/>
<field name="Z" start="30" end="30"/>
<field name="N" start="31" end="31"/>
</flags>
<reg name="cpsr" bitsize="32" type="cpsr_flags"/>
</feature>
</target>
)";
@ -143,12 +158,12 @@ WSADATA InitData;
struct Breakpoint {
bool active;
PAddr addr;
u32 len;
u64 len;
};
static std::map<u32, Breakpoint> breakpoints_execute;
static std::map<u32, Breakpoint> breakpoints_read;
static std::map<u32, Breakpoint> breakpoints_write;
static std::map<u64, Breakpoint> breakpoints_execute;
static std::map<u64, Breakpoint> breakpoints_read;
static std::map<u64, Breakpoint> breakpoints_write;
/**
* Turns hex string character into the equivalent byte.
@ -197,6 +212,21 @@ static u32 HexToInt(const u8* src, size_t len) {
return output;
}
/**
* Converts input hex string characters into an array of equivalent of u8 bytes.
*
* @param src Pointer to array of output hex string characters.
* @param len Length of src array.
*/
static u64 HexToLong(const u8* src, size_t len) {
u64 output = 0;
while (len-- > 0) {
output = (output << 4) | HexCharToValue(src[0]);
src++;
}
return output;
}
/**
* Converts input array of u8 bytes into their equivalent hex string characters.
*
@ -234,8 +264,21 @@ static void GdbHexToMem(u8* dest, const u8* src, size_t len) {
*/
static void IntToGdbHex(u8* dest, u32 v) {
for (int i = 0; i < 8; i += 2) {
dest[i + 1] = NibbleToHex(v >> (4 * i));
dest[i] = NibbleToHex(v >> (4 * (i + 1)));
dest[i + 1] = NibbleToHex(static_cast<u8>(v >> (4 * i)));
dest[i] = NibbleToHex(static_cast<u8>(v >> (4 * (i + 1))));
}
}
/**
* Convert a u64 into a gdb-formatted hex string.
*
* @param dest Pointer to buffer to store output hex string characters.
* @param v Value to convert.
*/
static void LongToGdbHex(u8* dest, u64 v) {
for (int i = 0; i < 16; i += 2) {
dest[i + 1] = NibbleToHex(static_cast<u8>(v >> (4 * i)));
dest[i] = NibbleToHex(static_cast<u8>(v >> (4 * (i + 1))));
}
}
@ -255,6 +298,22 @@ static u32 GdbHexToInt(const u8* src) {
return output;
}
/**
* Convert a gdb-formatted hex string into a u64.
*
* @param src Pointer to hex string.
*/
static u64 GdbHexToLong(const u8* src) {
u64 output = 0;
for (int i = 0; i < 16; i += 2) {
output = (output << 4) | HexCharToValue(src[15 - i - 1]);
output = (output << 4) | HexCharToValue(src[15 - i]);
}
return output;
}
/// Read a byte from the gdb client.
static u8 ReadByte() {
u8 c;
@ -277,7 +336,7 @@ static u8 CalculateChecksum(const u8* buffer, size_t length) {
*
* @param type Type of breakpoint list.
*/
static std::map<u32, Breakpoint>& GetBreakpointList(BreakpointType type) {
static std::map<u64, Breakpoint>& GetBreakpointList(BreakpointType type) {
switch (type) {
case BreakpointType::Execute:
return breakpoints_execute;
@ -297,19 +356,19 @@ static std::map<u32, Breakpoint>& GetBreakpointList(BreakpointType type) {
* @param addr Address of breakpoint.
*/
static void RemoveBreakpoint(BreakpointType type, PAddr addr) {
std::map<u32, Breakpoint>& p = GetBreakpointList(type);
std::map<u64, Breakpoint>& p = GetBreakpointList(type);
auto bp = p.find(static_cast<u32>(addr));
auto bp = p.find(static_cast<u64>(addr));
if (bp != p.end()) {
LOG_DEBUG(Debug_GDBStub, "gdb: removed a breakpoint: %08x bytes at %08x of type %d\n",
bp->second.len, bp->second.addr, type);
p.erase(static_cast<u32>(addr));
p.erase(static_cast<u64>(addr));
}
}
BreakpointAddress GetNextBreakpointFromAddress(PAddr addr, BreakpointType type) {
std::map<u32, Breakpoint>& p = GetBreakpointList(type);
auto next_breakpoint = p.lower_bound(static_cast<u32>(addr));
std::map<u64, Breakpoint>& p = GetBreakpointList(type);
auto next_breakpoint = p.lower_bound(static_cast<u64>(addr));
BreakpointAddress breakpoint;
if (next_breakpoint != p.end()) {
@ -328,11 +387,11 @@ bool CheckBreakpoint(PAddr addr, BreakpointType type) {
return false;
}
std::map<u32, Breakpoint>& p = GetBreakpointList(type);
std::map<u64, Breakpoint>& p = GetBreakpointList(type);
auto bp = p.find(static_cast<u32>(addr));
auto bp = p.find(static_cast<u64>(addr));
if (bp != p.end()) {
u32 len = bp->second.len;
u64 len = bp->second.len;
// IDA Pro defaults to 4-byte breakpoints for all non-hardware breakpoints
// no matter if it's a 4-byte or 2-byte instruction. When you execute a
@ -419,7 +478,7 @@ static void HandleQuery() {
SendReply("T0");
} else if (strncmp(query, "Supported", strlen("Supported")) == 0) {
// PacketSize needs to be large enough for target xml
SendReply("PacketSize=800;qXfer:features:read+");
SendReply("PacketSize=2000;qXfer:features:read+");
} else if (strncmp(query, "Xfer:features:read:target.xml:",
strlen("Xfer:features:read:target.xml:")) == 0) {
SendReply(target_xml);
@ -450,10 +509,7 @@ static void SendSignal(u32 signal) {
latest_signal = signal;
std::string buffer =
Common::StringFromFormat("T%02x%02x:%08x;%02x:%08x;", latest_signal, 15,
htonl(static_cast<u_long>(Core::CPU().GetPC())), 13,
htonl(static_cast<u_long>(Core::CPU().GetReg(13))));
std::string buffer = Common::StringFromFormat("T%02x", latest_signal);
LOG_DEBUG(Debug_GDBStub, "Response: %s", buffer.c_str());
SendReply(buffer.c_str());
}
@ -539,16 +595,12 @@ static void ReadRegister() {
id |= HexCharToValue(command_buffer[2]);
}
if (id <= R15_REGISTER) {
IntToGdbHex(reply, static_cast<u32>(Core::CPU().GetReg(static_cast<u64>(id))));
if (id <= SP_REGISTER) {
LongToGdbHex(reply, Core::CPU().GetReg(static_cast<int>(id)));
} else if (id == PC_REGISTER) {
LongToGdbHex(reply, Core::CPU().GetPC());
} else if (id == CPSR_REGISTER) {
IntToGdbHex(reply, Core::CPU().GetCPSR());
} else if (id > CPSR_REGISTER && id < FPSCR_REGISTER) {
IntToGdbHex(reply, Core::CPU().GetVFPReg(
id - CPSR_REGISTER -
1)); // VFP registers should start at 26, so one after CSPR_REGISTER
} else if (id == FPSCR_REGISTER) {
UNIMPLEMENTED();
} else {
return SendReply("E01");
}
@ -563,21 +615,19 @@ static void ReadRegisters() {
u8* bufptr = buffer;
for (int reg = 0; reg <= R15_REGISTER; reg++) {
IntToGdbHex(bufptr + reg * CHAR_BIT, static_cast<u32>(Core::CPU().GetReg(reg)));
for (int reg = 0; reg <= SP_REGISTER; reg++) {
LongToGdbHex(bufptr + reg * 16, Core::CPU().GetReg(reg));
}
bufptr += (16 * CHAR_BIT);
bufptr += (32 * 16);
LongToGdbHex(bufptr, Core::CPU().GetPC());
bufptr += 16;
IntToGdbHex(bufptr, Core::CPU().GetCPSR());
bufptr += CHAR_BIT;
for (int reg = 0; reg <= 31; reg++) {
IntToGdbHex(bufptr + reg * CHAR_BIT, Core::CPU().GetVFPReg(reg));
}
bufptr += (32 * CHAR_BIT);
bufptr += 8;
SendReply(reinterpret_cast<char*>(buffer));
}
@ -593,14 +643,12 @@ static void WriteRegister() {
id |= HexCharToValue(command_buffer[2]);
}
if (id <= R15_REGISTER) {
Core::CPU().SetReg(id, GdbHexToInt(buffer_ptr));
if (id <= SP_REGISTER) {
Core::CPU().SetReg(id, GdbHexToLong(buffer_ptr));
} else if (id == PC_REGISTER) {
Core::CPU().SetPC(GdbHexToLong(buffer_ptr));
} else if (id == CPSR_REGISTER) {
Core::CPU().SetCPSR(GdbHexToInt(buffer_ptr));
} else if (id > CPSR_REGISTER && id < FPSCR_REGISTER) {
Core::CPU().SetVFPReg(id - CPSR_REGISTER - 1, GdbHexToInt(buffer_ptr));
} else if (id == FPSCR_REGISTER) {
UNIMPLEMENTED();
} else {
return SendReply("E01");
}
@ -615,20 +663,14 @@ static void WriteRegisters() {
if (command_buffer[0] != 'G')
return SendReply("E01");
for (int i = 0, reg = 0; reg <= FPSCR_REGISTER; i++, reg++) {
if (reg <= R15_REGISTER) {
Core::CPU().SetReg(reg, GdbHexToInt(buffer_ptr + i * CHAR_BIT));
for (int i = 0, reg = 0; reg <= CPSR_REGISTER; i++, reg++) {
if (reg <= SP_REGISTER) {
Core::CPU().SetReg(reg, GdbHexToLong(buffer_ptr + i * 16));
} else if (reg == PC_REGISTER) {
Core::CPU().SetPC(GdbHexToLong(buffer_ptr + i * 16));
} else if (reg == CPSR_REGISTER) {
Core::CPU().SetCPSR(GdbHexToInt(buffer_ptr + i * CHAR_BIT));
} else if (reg == CPSR_REGISTER - 1) {
// Dummy FPA register, ignore
} else if (reg < CPSR_REGISTER) {
// Dummy FPA registers, ignore
i += 2;
} else if (reg > CPSR_REGISTER && reg < FPSCR_REGISTER) {
Core::CPU().SetVFPReg(reg - CPSR_REGISTER - 1, GdbHexToInt(buffer_ptr + i * CHAR_BIT));
i++; // Skip padding
} else if (reg == FPSCR_REGISTER) {
Core::CPU().SetCPSR(GdbHexToInt(buffer_ptr + i * 16));
} else {
UNIMPLEMENTED();
}
}
@ -642,13 +684,13 @@ static void ReadMemory() {
auto start_offset = command_buffer + 1;
auto addr_pos = std::find(start_offset, command_buffer + command_length, ',');
VAddr addr = HexToInt(start_offset, static_cast<u32>(addr_pos - start_offset));
VAddr addr = HexToLong(start_offset, static_cast<u64>(addr_pos - start_offset));
start_offset = addr_pos + 1;
u32 len =
HexToInt(start_offset, static_cast<u32>((command_buffer + command_length) - start_offset));
u64 len =
HexToLong(start_offset, static_cast<u64>((command_buffer + command_length) - start_offset));
LOG_DEBUG(Debug_GDBStub, "gdb: addr: %08x len: %08x\n", addr, len);
LOG_DEBUG(Debug_GDBStub, "gdb: addr: %016llx len: %016llx\n", addr, len);
if (len * 2 > sizeof(reply)) {
SendReply("E01");
@ -670,11 +712,11 @@ static void ReadMemory() {
static void WriteMemory() {
auto start_offset = command_buffer + 1;
auto addr_pos = std::find(start_offset, command_buffer + command_length, ',');
VAddr addr = HexToInt(start_offset, static_cast<u32>(addr_pos - start_offset));
VAddr addr = HexToLong(start_offset, static_cast<u64>(addr_pos - start_offset));
start_offset = addr_pos + 1;
auto len_pos = std::find(start_offset, command_buffer + command_length, ':');
u32 len = HexToInt(start_offset, static_cast<u32>(len_pos - start_offset));
u64 len = HexToLong(start_offset, static_cast<u64>(len_pos - start_offset));
if (!Memory::IsValidVirtualAddress(addr)) {
return SendReply("E00");
@ -727,8 +769,8 @@ static void Continue() {
* @param addr Address of breakpoint.
* @param len Length of breakpoint.
*/
static bool CommitBreakpoint(BreakpointType type, PAddr addr, u32 len) {
std::map<u32, Breakpoint>& p = GetBreakpointList(type);
static bool CommitBreakpoint(BreakpointType type, PAddr addr, u64 len) {
std::map<u64, Breakpoint>& p = GetBreakpointList(type);
Breakpoint breakpoint;
breakpoint.active = true;
@ -767,11 +809,11 @@ static void AddBreakpoint() {
auto start_offset = command_buffer + 3;
auto addr_pos = std::find(start_offset, command_buffer + command_length, ',');
PAddr addr = HexToInt(start_offset, static_cast<u32>(addr_pos - start_offset));
PAddr addr = HexToLong(start_offset, static_cast<u64>(addr_pos - start_offset));
start_offset = addr_pos + 1;
u32 len =
HexToInt(start_offset, static_cast<u32>((command_buffer + command_length) - start_offset));
u64 len =
HexToLong(start_offset, static_cast<u64>((command_buffer + command_length) - start_offset));
if (type == BreakpointType::Access) {
// Access is made up of Read and Write types, so add both breakpoints
@ -816,7 +858,7 @@ static void RemoveBreakpoint() {
auto start_offset = command_buffer + 3;
auto addr_pos = std::find(start_offset, command_buffer + command_length, ',');
PAddr addr = HexToInt(start_offset, static_cast<u32>(addr_pos - start_offset));
PAddr addr = HexToLong(start_offset, static_cast<u64>(addr_pos - start_offset));
if (type == BreakpointType::Access) {
// Access is made up of Read and Write types, so add both breakpoints