llvm-project/lldb/source/Commands/CommandObjectDisassemble.cpp
Adrian Prantl 0642cd768b
[lldb] Turn lldb_private::Status into a value type. (#106163)
This patch removes all of the Set.* methods from Status.

This cleanup is part of a series of patches that make it harder use the
anti-pattern of keeping a long-lives Status object around and updating
it while dropping any errors it contains on the floor.

This patch is largely NFC, the more interesting next steps this enables
is to:
1. remove Status.Clear()
2. assert that Status::operator=() never overwrites an error
3. remove Status::operator=()

Note that step (2) will bring 90% of the benefits for users, and step
(3) will dramatically clean up the error handling code in various
places. In the end my goal is to convert all APIs that are of the form

`    ResultTy DoFoo(Status& error)
`
to

`    llvm::Expected<ResultTy> DoFoo()
`
How to read this patch?

The interesting changes are in Status.h and Status.cpp, all other
changes are mostly

` perl -pi -e 's/\.SetErrorString/ = Status::FromErrorString/g' $(git
grep -l SetErrorString lldb/source)
`
plus the occasional manual cleanup.
2024-08-27 10:59:31 -07:00

546 lines
18 KiB
C++

//===-- CommandObjectDisassemble.cpp --------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "CommandObjectDisassemble.h"
#include "lldb/Core/AddressRange.h"
#include "lldb/Core/Disassembler.h"
#include "lldb/Core/Module.h"
#include "lldb/Host/OptionParser.h"
#include "lldb/Interpreter/CommandInterpreter.h"
#include "lldb/Interpreter/CommandOptionArgumentTable.h"
#include "lldb/Interpreter/CommandReturnObject.h"
#include "lldb/Interpreter/OptionArgParser.h"
#include "lldb/Interpreter/Options.h"
#include "lldb/Symbol/Function.h"
#include "lldb/Symbol/Symbol.h"
#include "lldb/Target/SectionLoadList.h"
#include "lldb/Target/StackFrame.h"
#include "lldb/Target/Target.h"
static constexpr unsigned default_disasm_byte_size = 32;
static constexpr unsigned default_disasm_num_ins = 4;
using namespace lldb;
using namespace lldb_private;
#define LLDB_OPTIONS_disassemble
#include "CommandOptions.inc"
CommandObjectDisassemble::CommandOptions::CommandOptions() {
OptionParsingStarting(nullptr);
}
CommandObjectDisassemble::CommandOptions::~CommandOptions() = default;
Status CommandObjectDisassemble::CommandOptions::SetOptionValue(
uint32_t option_idx, llvm::StringRef option_arg,
ExecutionContext *execution_context) {
Status error;
const int short_option = m_getopt_table[option_idx].val;
switch (short_option) {
case 'm':
show_mixed = true;
break;
case 'C':
if (option_arg.getAsInteger(0, num_lines_context))
error = Status::FromErrorStringWithFormat(
"invalid num context lines string: \"%s\"", option_arg.str().c_str());
break;
case 'c':
if (option_arg.getAsInteger(0, num_instructions))
error = Status::FromErrorStringWithFormat(
"invalid num of instructions string: \"%s\"",
option_arg.str().c_str());
break;
case 'b':
show_bytes = true;
break;
case 'k':
show_control_flow_kind = true;
break;
case 's': {
start_addr = OptionArgParser::ToAddress(execution_context, option_arg,
LLDB_INVALID_ADDRESS, &error);
if (start_addr != LLDB_INVALID_ADDRESS)
some_location_specified = true;
} break;
case 'e': {
end_addr = OptionArgParser::ToAddress(execution_context, option_arg,
LLDB_INVALID_ADDRESS, &error);
if (end_addr != LLDB_INVALID_ADDRESS)
some_location_specified = true;
} break;
case 'n':
func_name.assign(std::string(option_arg));
some_location_specified = true;
break;
case 'p':
at_pc = true;
some_location_specified = true;
break;
case 'l':
frame_line = true;
// Disassemble the current source line kind of implies showing mixed source
// code context.
show_mixed = true;
some_location_specified = true;
break;
case 'P':
plugin_name.assign(std::string(option_arg));
break;
case 'F': {
TargetSP target_sp =
execution_context ? execution_context->GetTargetSP() : TargetSP();
if (target_sp && (target_sp->GetArchitecture().GetTriple().getArch() ==
llvm::Triple::x86 ||
target_sp->GetArchitecture().GetTriple().getArch() ==
llvm::Triple::x86_64)) {
flavor_string.assign(std::string(option_arg));
} else
error = Status::FromErrorStringWithFormat(
"Disassembler flavors are currently only "
"supported for x86 and x86_64 targets.");
break;
}
case 'r':
raw = true;
break;
case 'f':
current_function = true;
some_location_specified = true;
break;
case 'A':
if (execution_context) {
const auto &target_sp = execution_context->GetTargetSP();
auto platform_ptr = target_sp ? target_sp->GetPlatform().get() : nullptr;
arch = Platform::GetAugmentedArchSpec(platform_ptr, option_arg);
}
break;
case 'a': {
symbol_containing_addr = OptionArgParser::ToAddress(
execution_context, option_arg, LLDB_INVALID_ADDRESS, &error);
if (symbol_containing_addr != LLDB_INVALID_ADDRESS) {
some_location_specified = true;
}
} break;
case '\x01':
force = true;
break;
default:
llvm_unreachable("Unimplemented option");
}
return error;
}
void CommandObjectDisassemble::CommandOptions::OptionParsingStarting(
ExecutionContext *execution_context) {
show_mixed = false;
show_bytes = false;
show_control_flow_kind = false;
num_lines_context = 0;
num_instructions = 0;
func_name.clear();
current_function = false;
at_pc = false;
frame_line = false;
start_addr = LLDB_INVALID_ADDRESS;
end_addr = LLDB_INVALID_ADDRESS;
symbol_containing_addr = LLDB_INVALID_ADDRESS;
raw = false;
plugin_name.clear();
Target *target =
execution_context ? execution_context->GetTargetPtr() : nullptr;
// This is a hack till we get the ability to specify features based on
// architecture. For now GetDisassemblyFlavor is really only valid for x86
// (and for the llvm assembler plugin, but I'm papering over that since that
// is the only disassembler plugin we have...
if (target) {
if (target->GetArchitecture().GetTriple().getArch() == llvm::Triple::x86 ||
target->GetArchitecture().GetTriple().getArch() ==
llvm::Triple::x86_64) {
flavor_string.assign(target->GetDisassemblyFlavor());
} else
flavor_string.assign("default");
} else
flavor_string.assign("default");
arch.Clear();
some_location_specified = false;
force = false;
}
Status CommandObjectDisassemble::CommandOptions::OptionParsingFinished(
ExecutionContext *execution_context) {
if (!some_location_specified)
current_function = true;
return Status();
}
llvm::ArrayRef<OptionDefinition>
CommandObjectDisassemble::CommandOptions::GetDefinitions() {
return llvm::ArrayRef(g_disassemble_options);
}
// CommandObjectDisassemble
CommandObjectDisassemble::CommandObjectDisassemble(
CommandInterpreter &interpreter)
: CommandObjectParsed(
interpreter, "disassemble",
"Disassemble specified instructions in the current target. "
"Defaults to the current function for the current thread and "
"stack frame.",
"disassemble [<cmd-options>]", eCommandRequiresTarget) {}
CommandObjectDisassemble::~CommandObjectDisassemble() = default;
llvm::Error CommandObjectDisassemble::CheckRangeSize(const AddressRange &range,
llvm::StringRef what) {
if (m_options.num_instructions > 0 || m_options.force ||
range.GetByteSize() < GetDebugger().GetStopDisassemblyMaxSize())
return llvm::Error::success();
StreamString msg;
msg << "Not disassembling " << what << " because it is very large ";
range.Dump(&msg, &GetTarget(), Address::DumpStyleLoadAddress,
Address::DumpStyleFileAddress);
msg << ". To disassemble specify an instruction count limit, start/stop "
"addresses or use the --force option.";
return llvm::createStringError(llvm::inconvertibleErrorCode(),
msg.GetString());
}
llvm::Expected<std::vector<AddressRange>>
CommandObjectDisassemble::GetContainingAddressRanges() {
std::vector<AddressRange> ranges;
const auto &get_range = [&](Address addr) {
ModuleSP module_sp(addr.GetModule());
SymbolContext sc;
bool resolve_tail_call_address = true;
addr.GetModule()->ResolveSymbolContextForAddress(
addr, eSymbolContextEverything, sc, resolve_tail_call_address);
if (sc.function || sc.symbol) {
AddressRange range;
sc.GetAddressRange(eSymbolContextFunction | eSymbolContextSymbol, 0,
false, range);
ranges.push_back(range);
}
};
Target &target = GetTarget();
if (!target.GetSectionLoadList().IsEmpty()) {
Address symbol_containing_address;
if (target.GetSectionLoadList().ResolveLoadAddress(
m_options.symbol_containing_addr, symbol_containing_address)) {
get_range(symbol_containing_address);
}
} else {
for (lldb::ModuleSP module_sp : target.GetImages().Modules()) {
Address file_address;
if (module_sp->ResolveFileAddress(m_options.symbol_containing_addr,
file_address)) {
get_range(file_address);
}
}
}
if (ranges.empty()) {
return llvm::createStringError(
llvm::inconvertibleErrorCode(),
"Could not find function bounds for address 0x%" PRIx64,
m_options.symbol_containing_addr);
}
if (llvm::Error err = CheckRangeSize(ranges[0], "the function"))
return std::move(err);
return ranges;
}
llvm::Expected<std::vector<AddressRange>>
CommandObjectDisassemble::GetCurrentFunctionRanges() {
Process *process = m_exe_ctx.GetProcessPtr();
StackFrame *frame = m_exe_ctx.GetFramePtr();
if (!frame) {
if (process) {
return llvm::createStringError(
llvm::inconvertibleErrorCode(),
"Cannot disassemble around the current "
"function without the process being stopped.\n");
} else {
return llvm::createStringError(llvm::inconvertibleErrorCode(),
"Cannot disassemble around the current "
"function without a selected frame: "
"no currently running process.\n");
}
}
SymbolContext sc(
frame->GetSymbolContext(eSymbolContextFunction | eSymbolContextSymbol));
AddressRange range;
if (sc.function)
range = sc.function->GetAddressRange();
else if (sc.symbol && sc.symbol->ValueIsAddress()) {
range = {sc.symbol->GetAddress(), sc.symbol->GetByteSize()};
} else
range = {frame->GetFrameCodeAddress(), default_disasm_byte_size};
if (llvm::Error err = CheckRangeSize(range, "the current function"))
return std::move(err);
return std::vector<AddressRange>{range};
}
llvm::Expected<std::vector<AddressRange>>
CommandObjectDisassemble::GetCurrentLineRanges() {
Process *process = m_exe_ctx.GetProcessPtr();
StackFrame *frame = m_exe_ctx.GetFramePtr();
if (!frame) {
if (process) {
return llvm::createStringError(
llvm::inconvertibleErrorCode(),
"Cannot disassemble around the current "
"function without the process being stopped.\n");
} else {
return llvm::createStringError(llvm::inconvertibleErrorCode(),
"Cannot disassemble around the current "
"line without a selected frame: "
"no currently running process.\n");
}
}
LineEntry pc_line_entry(
frame->GetSymbolContext(eSymbolContextLineEntry).line_entry);
if (pc_line_entry.IsValid())
return std::vector<AddressRange>{pc_line_entry.range};
// No line entry, so just disassemble around the current pc
m_options.show_mixed = false;
return GetPCRanges();
}
llvm::Expected<std::vector<AddressRange>>
CommandObjectDisassemble::GetNameRanges(CommandReturnObject &result) {
ConstString name(m_options.func_name.c_str());
ModuleFunctionSearchOptions function_options;
function_options.include_symbols = true;
function_options.include_inlines = true;
// Find functions matching the given name.
SymbolContextList sc_list;
GetTarget().GetImages().FindFunctions(name, eFunctionNameTypeAuto,
function_options, sc_list);
std::vector<AddressRange> ranges;
llvm::Error range_errs = llvm::Error::success();
AddressRange range;
const uint32_t scope =
eSymbolContextBlock | eSymbolContextFunction | eSymbolContextSymbol;
const bool use_inline_block_range = true;
for (SymbolContext sc : sc_list.SymbolContexts()) {
for (uint32_t range_idx = 0;
sc.GetAddressRange(scope, range_idx, use_inline_block_range, range);
++range_idx) {
if (llvm::Error err = CheckRangeSize(range, "a range"))
range_errs = joinErrors(std::move(range_errs), std::move(err));
else
ranges.push_back(range);
}
}
if (ranges.empty()) {
if (range_errs)
return std::move(range_errs);
return llvm::createStringError(llvm::inconvertibleErrorCode(),
"Unable to find symbol with name '%s'.\n",
name.GetCString());
}
if (range_errs)
result.AppendWarning(toString(std::move(range_errs)));
return ranges;
}
llvm::Expected<std::vector<AddressRange>>
CommandObjectDisassemble::GetPCRanges() {
Process *process = m_exe_ctx.GetProcessPtr();
StackFrame *frame = m_exe_ctx.GetFramePtr();
if (!frame) {
if (process) {
return llvm::createStringError(
llvm::inconvertibleErrorCode(),
"Cannot disassemble around the current "
"function without the process being stopped.\n");
} else {
return llvm::createStringError(llvm::inconvertibleErrorCode(),
"Cannot disassemble around the current "
"PC without a selected frame: "
"no currently running process.\n");
}
}
if (m_options.num_instructions == 0) {
// Disassembling at the PC always disassembles some number of
// instructions (not the whole function).
m_options.num_instructions = default_disasm_num_ins;
}
return std::vector<AddressRange>{{frame->GetFrameCodeAddress(), 0}};
}
llvm::Expected<std::vector<AddressRange>>
CommandObjectDisassemble::GetStartEndAddressRanges() {
addr_t size = 0;
if (m_options.end_addr != LLDB_INVALID_ADDRESS) {
if (m_options.end_addr <= m_options.start_addr) {
return llvm::createStringError(llvm::inconvertibleErrorCode(),
"End address before start address.");
}
size = m_options.end_addr - m_options.start_addr;
}
return std::vector<AddressRange>{{Address(m_options.start_addr), size}};
}
llvm::Expected<std::vector<AddressRange>>
CommandObjectDisassemble::GetRangesForSelectedMode(
CommandReturnObject &result) {
if (m_options.symbol_containing_addr != LLDB_INVALID_ADDRESS)
return CommandObjectDisassemble::GetContainingAddressRanges();
if (m_options.current_function)
return CommandObjectDisassemble::GetCurrentFunctionRanges();
if (m_options.frame_line)
return CommandObjectDisassemble::GetCurrentLineRanges();
if (!m_options.func_name.empty())
return CommandObjectDisassemble::GetNameRanges(result);
if (m_options.start_addr != LLDB_INVALID_ADDRESS)
return CommandObjectDisassemble::GetStartEndAddressRanges();
return CommandObjectDisassemble::GetPCRanges();
}
void CommandObjectDisassemble::DoExecute(Args &command,
CommandReturnObject &result) {
Target &target = GetTarget();
if (!m_options.arch.IsValid())
m_options.arch = target.GetArchitecture();
if (!m_options.arch.IsValid()) {
result.AppendError(
"use the --arch option or set the target architecture to disassemble");
return;
}
const char *plugin_name = m_options.GetPluginName();
const char *flavor_string = m_options.GetFlavorString();
DisassemblerSP disassembler =
Disassembler::FindPlugin(m_options.arch, flavor_string, plugin_name);
if (!disassembler) {
if (plugin_name) {
result.AppendErrorWithFormat(
"Unable to find Disassembler plug-in named '%s' that supports the "
"'%s' architecture.\n",
plugin_name, m_options.arch.GetArchitectureName());
} else
result.AppendErrorWithFormat(
"Unable to find Disassembler plug-in for the '%s' architecture.\n",
m_options.arch.GetArchitectureName());
return;
} else if (flavor_string != nullptr && !disassembler->FlavorValidForArchSpec(
m_options.arch, flavor_string))
result.AppendWarningWithFormat(
"invalid disassembler flavor \"%s\", using default.\n", flavor_string);
result.SetStatus(eReturnStatusSuccessFinishResult);
if (!command.empty()) {
result.AppendErrorWithFormat(
"\"disassemble\" arguments are specified as options.\n");
const int terminal_width =
GetCommandInterpreter().GetDebugger().GetTerminalWidth();
GetOptions()->GenerateOptionUsage(result.GetErrorStream(), *this,
terminal_width);
return;
}
if (m_options.show_mixed && m_options.num_lines_context == 0)
m_options.num_lines_context = 2;
// Always show the PC in the disassembly
uint32_t options = Disassembler::eOptionMarkPCAddress;
// Mark the source line for the current PC only if we are doing mixed source
// and assembly
if (m_options.show_mixed)
options |= Disassembler::eOptionMarkPCSourceLine;
if (m_options.show_bytes)
options |= Disassembler::eOptionShowBytes;
if (m_options.show_control_flow_kind)
options |= Disassembler::eOptionShowControlFlowKind;
if (m_options.raw)
options |= Disassembler::eOptionRawOuput;
llvm::Expected<std::vector<AddressRange>> ranges =
GetRangesForSelectedMode(result);
if (!ranges) {
result.AppendError(toString(ranges.takeError()));
return;
}
bool print_sc_header = ranges->size() > 1;
for (AddressRange cur_range : *ranges) {
Disassembler::Limit limit;
if (m_options.num_instructions == 0) {
limit = {Disassembler::Limit::Bytes, cur_range.GetByteSize()};
if (limit.value == 0)
limit.value = default_disasm_byte_size;
} else {
limit = {Disassembler::Limit::Instructions, m_options.num_instructions};
}
if (Disassembler::Disassemble(
GetDebugger(), m_options.arch, plugin_name, flavor_string,
m_exe_ctx, cur_range.GetBaseAddress(), limit, m_options.show_mixed,
m_options.show_mixed ? m_options.num_lines_context : 0, options,
result.GetOutputStream())) {
result.SetStatus(eReturnStatusSuccessFinishResult);
} else {
if (m_options.symbol_containing_addr != LLDB_INVALID_ADDRESS) {
result.AppendErrorWithFormat(
"Failed to disassemble memory in function at 0x%8.8" PRIx64 ".\n",
m_options.symbol_containing_addr);
} else {
result.AppendErrorWithFormat(
"Failed to disassemble memory at 0x%8.8" PRIx64 ".\n",
cur_range.GetBaseAddress().GetLoadAddress(&target));
}
}
if (print_sc_header)
result.GetOutputStream() << "\n";
}
}