Support custom expedited register set in gdb-remote

This patch adds capability to introduce a custom expedited register set
in gdb remote. Currently we send register set 0 as expedited register set
but for the case of AArch64 SVE we intend to send additional information
about SVE registers size/offset configuration which can be calculated
from vg register. Therefore we will expedited Vg register in case of
AArch64 is in SVE mode to speedup register configuration calculations.

Reviewed By: labath

Differential Revision: https://reviews.llvm.org/D82853
This commit is contained in:
Muhammad Omair Javaid 2020-11-26 12:55:28 +05:00
parent 5110ff0817
commit b69c09bf43
3 changed files with 62 additions and 65 deletions

View File

@ -16,6 +16,8 @@ namespace lldb_private {
class NativeThreadProtocol;
enum class ExpeditedRegs { Minimal, Full };
class NativeRegisterContext
: public std::enable_shared_from_this<NativeRegisterContext> {
public:
@ -116,6 +118,9 @@ public:
virtual NativeThreadProtocol &GetThread() { return m_thread; }
virtual std::vector<uint32_t>
GetExpeditedRegisters(ExpeditedRegs expType) const;
const RegisterInfo *GetRegisterInfoByName(llvm::StringRef reg_name,
uint32_t start_idx = 0);

View File

@ -424,3 +424,32 @@ NativeRegisterContext::ConvertRegisterKindToRegisterNumber(uint32_t kind,
return LLDB_INVALID_REGNUM;
}
std::vector<uint32_t>
NativeRegisterContext::GetExpeditedRegisters(ExpeditedRegs expType) const {
if (expType == ExpeditedRegs::Minimal) {
// Expedite only a minimum set of important generic registers.
static const uint32_t k_expedited_registers[] = {
LLDB_REGNUM_GENERIC_PC, LLDB_REGNUM_GENERIC_SP, LLDB_REGNUM_GENERIC_FP,
LLDB_REGNUM_GENERIC_RA};
std::vector<uint32_t> expedited_reg_nums;
for (uint32_t gen_reg : k_expedited_registers) {
uint32_t reg_num =
ConvertRegisterKindToRegisterNumber(eRegisterKindGeneric, gen_reg);
if (reg_num == LLDB_INVALID_REGNUM)
continue; // Target does not support the given register.
else
expedited_reg_nums.push_back(reg_num);
}
return expedited_reg_nums;
}
if (GetRegisterSetCount() > 0 && expType == ExpeditedRegs::Full)
return std::vector<uint32_t>(GetRegisterSet(0)->registers,
GetRegisterSet(0)->registers +
GetRegisterSet(0)->num_registers);
return std::vector<uint32_t>();
}

View File

@ -503,7 +503,7 @@ static void WriteRegisterValueInHexFixedWidth(
}
}
static llvm::Expected<json::Object>
static llvm::Optional<json::Object>
GetRegistersAsJSON(NativeThreadProtocol &thread) {
Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_THREAD));
@ -512,30 +512,16 @@ GetRegistersAsJSON(NativeThreadProtocol &thread) {
json::Object register_object;
#ifdef LLDB_JTHREADSINFO_FULL_REGISTER_SET
// Expedite all registers in the first register set (i.e. should be GPRs)
// that are not contained in other registers.
const RegisterSet *reg_set_p = reg_ctx_sp->GetRegisterSet(0);
if (!reg_set_p)
return llvm::make_error<llvm::StringError>("failed to get registers",
llvm::inconvertibleErrorCode());
for (const uint32_t *reg_num_p = reg_set_p->registers;
*reg_num_p != LLDB_INVALID_REGNUM; ++reg_num_p) {
uint32_t reg_num = *reg_num_p;
const auto expedited_regs =
reg_ctx.GetExpeditedRegisters(ExpeditedRegs::Full);
#else
// Expedite only a couple of registers until we figure out why sending
// registers is expensive.
static const uint32_t k_expedited_registers[] = {
LLDB_REGNUM_GENERIC_PC, LLDB_REGNUM_GENERIC_SP, LLDB_REGNUM_GENERIC_FP,
LLDB_REGNUM_GENERIC_RA, LLDB_INVALID_REGNUM};
for (const uint32_t *generic_reg_p = k_expedited_registers;
*generic_reg_p != LLDB_INVALID_REGNUM; ++generic_reg_p) {
uint32_t reg_num = reg_ctx.ConvertRegisterKindToRegisterNumber(
eRegisterKindGeneric, *generic_reg_p);
if (reg_num == LLDB_INVALID_REGNUM)
continue; // Target does not support the given register.
const auto expedited_regs =
reg_ctx.GetExpeditedRegisters(ExpeditedRegs::Minimal);
#endif
if (expedited_regs.empty())
return llvm::None;
for (auto &reg_num : expedited_regs) {
const RegisterInfo *const reg_info_p =
reg_ctx.GetRegisterInfoAtIndex(reg_num);
if (reg_info_p == nullptr) {
@ -628,12 +614,8 @@ GetJSONThreadsInfo(NativeProcessProtocol &process, bool abridged) {
json::Object thread_obj;
if (!abridged) {
if (llvm::Expected<json::Object> registers =
GetRegistersAsJSON(*thread)) {
if (llvm::Optional<json::Object> registers = GetRegistersAsJSON(*thread))
thread_obj.try_emplace("registers", std::move(*registers));
} else {
return registers.takeError();
}
}
thread_obj.try_emplace("tid", static_cast<int64_t>(tid));
@ -814,46 +796,27 @@ GDBRemoteCommunicationServerLLGS::SendStopReplyPacketForThread(
// Grab the register context.
NativeRegisterContext& reg_ctx = thread->GetRegisterContext();
// Expedite all registers in the first register set (i.e. should be GPRs)
// that are not contained in other registers.
const RegisterSet *reg_set_p;
if (reg_ctx.GetRegisterSetCount() > 0 &&
((reg_set_p = reg_ctx.GetRegisterSet(0)) != nullptr)) {
LLDB_LOGF(log,
"GDBRemoteCommunicationServerLLGS::%s expediting registers "
"from set '%s' (registers set count: %zu)",
__FUNCTION__, reg_set_p->name ? reg_set_p->name : "<unnamed-set>",
reg_set_p->num_registers);
const auto expedited_regs =
reg_ctx.GetExpeditedRegisters(ExpeditedRegs::Full);
for (const uint32_t *reg_num_p = reg_set_p->registers;
*reg_num_p != LLDB_INVALID_REGNUM; ++reg_num_p) {
const RegisterInfo *const reg_info_p =
reg_ctx.GetRegisterInfoAtIndex(*reg_num_p);
if (reg_info_p == nullptr) {
LLDB_LOGF(log,
"GDBRemoteCommunicationServerLLGS::%s failed to get "
"register info for register set '%s', register index "
"%" PRIu32,
for (auto &reg_num : expedited_regs) {
const RegisterInfo *const reg_info_p =
reg_ctx.GetRegisterInfoAtIndex(reg_num);
// Only expediate registers that are not contained in other registers.
if (reg_info_p != nullptr && reg_info_p->value_regs == nullptr) {
RegisterValue reg_value;
Status error = reg_ctx.ReadRegister(reg_info_p, reg_value);
if (error.Success()) {
response.Printf("%.02x:", reg_num);
WriteRegisterValueInHexFixedWidth(response, reg_ctx, *reg_info_p,
&reg_value, lldb::eByteOrderBig);
response.PutChar(';');
} else {
LLDB_LOGF(log, "GDBRemoteCommunicationServerLLGS::%s failed to read "
"register '%s' index %" PRIu32 ": %s",
__FUNCTION__,
reg_set_p->name ? reg_set_p->name : "<unnamed-set>",
*reg_num_p);
} else if (reg_info_p->value_regs == nullptr) {
// Only expediate registers that are not contained in other registers.
RegisterValue reg_value;
Status error = reg_ctx.ReadRegister(reg_info_p, reg_value);
if (error.Success()) {
response.Printf("%.02x:", *reg_num_p);
WriteRegisterValueInHexFixedWidth(response, reg_ctx, *reg_info_p,
&reg_value, lldb::eByteOrderBig);
response.PutChar(';');
} else {
LLDB_LOGF(log,
"GDBRemoteCommunicationServerLLGS::%s failed to read "
"register '%s' index %" PRIu32 ": %s",
__FUNCTION__,
reg_info_p->name ? reg_info_p->name : "<unnamed-register>",
*reg_num_p, error.AsCString());
}
reg_info_p->name ? reg_info_p->name : "<unnamed-register>",
reg_num, error.AsCString());
}
}
}