Files
llvm/lldb/source/Commands/CommandObjectDisassemble.cpp
Raphael Isemann 36162014c4 [lldb][NFC] Remove dead code that is supposed to handle invalid command options
Summary:
We currently have a bunch of code that is supposed to handle invalid command options, but
all this code is unreachable because invalid options are already handled in `Options::Parse`.
The only way we can reach this code is when we declare but then not implement an option
(which will be made impossible with D65386, which is also when we can completely remove
the `default` cases).

This patch replaces all this code with `llvm_unreachable` to make clear this is dead code
that can't be reached.

Reviewers: JDevlieghere

Reviewed By: JDevlieghere

Subscribers: lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D66522

llvm-svn: 369625
2019-08-22 08:08:05 +00:00

529 lines
19 KiB
C++

//===-- CommandObjectDisassemble.cpp ----------------------------*- C++ -*-===//
//
// 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/Core/SourceManager.h"
#include "lldb/Host/OptionParser.h"
#include "lldb/Interpreter/CommandCompletions.h"
#include "lldb/Interpreter/CommandInterpreter.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/Process.h"
#include "lldb/Target/SectionLoadList.h"
#include "lldb/Target/StackFrame.h"
#include "lldb/Target/Target.h"
#define DEFAULT_DISASM_BYTE_SIZE 32
#define DEFAULT_DISASM_NUM_INS 4
using namespace lldb;
using namespace lldb_private;
#define LLDB_OPTIONS_disassemble
#include "CommandOptions.inc"
CommandObjectDisassemble::CommandOptions::CommandOptions()
: Options(), num_lines_context(0), num_instructions(0), func_name(),
current_function(false), start_addr(), end_addr(), at_pc(false),
frame_line(false), plugin_name(), flavor_string(), arch(),
some_location_specified(false), symbol_containing_addr() {
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.SetErrorStringWithFormat("invalid num context lines string: \"%s\"",
option_arg.str().c_str());
break;
case 'c':
if (option_arg.getAsInteger(0, num_instructions))
error.SetErrorStringWithFormat(
"invalid num of instructions string: \"%s\"",
option_arg.str().c_str());
break;
case 'b':
show_bytes = 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(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(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(option_arg);
} else
error.SetErrorStringWithFormat("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;
default:
llvm_unreachable("Unimplemented option");
}
return error;
}
void CommandObjectDisassemble::CommandOptions::OptionParsingStarting(
ExecutionContext *execution_context) {
show_mixed = false;
show_bytes = 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;
}
Status CommandObjectDisassemble::CommandOptions::OptionParsingFinished(
ExecutionContext *execution_context) {
if (!some_location_specified)
current_function = true;
return Status();
}
llvm::ArrayRef<OptionDefinition>
CommandObjectDisassemble::CommandOptions::GetDefinitions() {
return llvm::makeArrayRef(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>]"),
m_options() {}
CommandObjectDisassemble::~CommandObjectDisassemble() = default;
bool CommandObjectDisassemble::DoExecute(Args &command,
CommandReturnObject &result) {
Target *target = GetDebugger().GetSelectedTarget().get();
if (target == nullptr) {
result.AppendError("invalid target, create a debug target using the "
"'target create' command");
result.SetStatus(eReturnStatusFailed);
return false;
}
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");
result.SetStatus(eReturnStatusFailed);
return false;
}
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());
result.SetStatus(eReturnStatusFailed);
return false;
} 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);
result.SetStatus(eReturnStatusFailed);
return false;
}
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.raw)
options |= Disassembler::eOptionRawOuput;
if (!m_options.func_name.empty()) {
ConstString name(m_options.func_name.c_str());
if (Disassembler::Disassemble(
GetDebugger(), m_options.arch, plugin_name, flavor_string,
m_exe_ctx, name,
nullptr, // Module *
m_options.num_instructions, m_options.show_mixed,
m_options.show_mixed ? m_options.num_lines_context : 0, options,
result.GetOutputStream())) {
result.SetStatus(eReturnStatusSuccessFinishResult);
} else {
result.AppendErrorWithFormat("Unable to find symbol with name '%s'.\n",
name.GetCString());
result.SetStatus(eReturnStatusFailed);
}
} else {
std::vector<AddressRange> ranges;
AddressRange range;
StackFrame *frame = m_exe_ctx.GetFramePtr();
if (m_options.frame_line) {
if (frame == nullptr) {
result.AppendError("Cannot disassemble around the current line without "
"a selected frame.\n");
result.SetStatus(eReturnStatusFailed);
return false;
}
LineEntry pc_line_entry(
frame->GetSymbolContext(eSymbolContextLineEntry).line_entry);
if (pc_line_entry.IsValid()) {
range = pc_line_entry.range;
} else {
m_options.at_pc =
true; // No line entry, so just disassemble around the current pc
m_options.show_mixed = false;
}
} else if (m_options.current_function) {
if (frame == nullptr) {
result.AppendError("Cannot disassemble around the current function "
"without a selected frame.\n");
result.SetStatus(eReturnStatusFailed);
return false;
}
Symbol *symbol = frame->GetSymbolContext(eSymbolContextSymbol).symbol;
if (symbol) {
range.GetBaseAddress() = symbol->GetAddress();
range.SetByteSize(symbol->GetByteSize());
}
}
// Did the "m_options.frame_line" find a valid range already? If so skip
// the rest...
if (range.GetByteSize() == 0) {
if (m_options.at_pc) {
if (frame == nullptr) {
result.AppendError("Cannot disassemble around the current PC without "
"a selected frame.\n");
result.SetStatus(eReturnStatusFailed);
return false;
}
range.GetBaseAddress() = frame->GetFrameCodeAddress();
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;
}
ranges.push_back(range);
} else {
range.GetBaseAddress().SetOffset(m_options.start_addr);
if (range.GetBaseAddress().IsValid()) {
if (m_options.end_addr != LLDB_INVALID_ADDRESS) {
if (m_options.end_addr <= m_options.start_addr) {
result.AppendErrorWithFormat(
"End address before start address.\n");
result.SetStatus(eReturnStatusFailed);
return false;
}
range.SetByteSize(m_options.end_addr - m_options.start_addr);
}
ranges.push_back(range);
} else {
if (m_options.symbol_containing_addr != LLDB_INVALID_ADDRESS &&
target) {
if (!target->GetSectionLoadList().IsEmpty()) {
bool failed = false;
Address symbol_containing_address;
if (target->GetSectionLoadList().ResolveLoadAddress(
m_options.symbol_containing_addr,
symbol_containing_address)) {
ModuleSP module_sp(symbol_containing_address.GetModule());
SymbolContext sc;
bool resolve_tail_call_address = true; // PC can be one past the
// address range of the
// function.
module_sp->ResolveSymbolContextForAddress(
symbol_containing_address, eSymbolContextEverything, sc,
resolve_tail_call_address);
if (sc.function || sc.symbol) {
sc.GetAddressRange(eSymbolContextFunction |
eSymbolContextSymbol,
0, false, range);
} else {
failed = true;
}
} else {
failed = true;
}
if (failed) {
result.AppendErrorWithFormat(
"Could not find function bounds for address 0x%" PRIx64
"\n",
m_options.symbol_containing_addr);
result.SetStatus(eReturnStatusFailed);
return false;
}
ranges.push_back(range);
} else {
for (lldb::ModuleSP module_sp : target->GetImages().Modules()) {
lldb::addr_t file_addr = m_options.symbol_containing_addr;
Address file_address;
if (module_sp->ResolveFileAddress(file_addr, file_address)) {
SymbolContext sc;
bool resolve_tail_call_address = true; // PC can be one past
// the address range of
// the function.
module_sp->ResolveSymbolContextForAddress(
file_address, eSymbolContextEverything, sc,
resolve_tail_call_address);
if (sc.function || sc.symbol) {
sc.GetAddressRange(eSymbolContextFunction |
eSymbolContextSymbol,
0, false, range);
ranges.push_back(range);
}
}
}
}
}
}
}
} else
ranges.push_back(range);
if (m_options.num_instructions != 0) {
if (ranges.empty()) {
// The default action is to disassemble the current frame function.
if (frame) {
SymbolContext sc(frame->GetSymbolContext(eSymbolContextFunction |
eSymbolContextSymbol));
if (sc.function)
range.GetBaseAddress() =
sc.function->GetAddressRange().GetBaseAddress();
else if (sc.symbol && sc.symbol->ValueIsAddress())
range.GetBaseAddress() = sc.symbol->GetAddress();
else
range.GetBaseAddress() = frame->GetFrameCodeAddress();
}
if (!range.GetBaseAddress().IsValid()) {
result.AppendError("invalid frame");
result.SetStatus(eReturnStatusFailed);
return false;
}
}
bool print_sc_header = ranges.size() > 1;
for (AddressRange cur_range : ranges) {
if (Disassembler::Disassemble(
GetDebugger(), m_options.arch, plugin_name, flavor_string,
m_exe_ctx, cur_range.GetBaseAddress(),
m_options.num_instructions, m_options.show_mixed,
m_options.show_mixed ? m_options.num_lines_context : 0, options,
result.GetOutputStream())) {
result.SetStatus(eReturnStatusSuccessFinishResult);
} else {
if (m_options.start_addr != LLDB_INVALID_ADDRESS)
result.AppendErrorWithFormat(
"Failed to disassemble memory at 0x%8.8" PRIx64 ".\n",
m_options.start_addr);
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);
result.SetStatus(eReturnStatusFailed);
}
}
if (print_sc_header)
result.AppendMessage("\n");
} else {
if (ranges.empty()) {
// The default action is to disassemble the current frame function.
if (frame) {
SymbolContext sc(frame->GetSymbolContext(eSymbolContextFunction |
eSymbolContextSymbol));
if (sc.function)
range = sc.function->GetAddressRange();
else if (sc.symbol && sc.symbol->ValueIsAddress()) {
range.GetBaseAddress() = sc.symbol->GetAddress();
range.SetByteSize(sc.symbol->GetByteSize());
} else
range.GetBaseAddress() = frame->GetFrameCodeAddress();
} else {
result.AppendError("invalid frame");
result.SetStatus(eReturnStatusFailed);
return false;
}
ranges.push_back(range);
}
bool print_sc_header = ranges.size() > 1;
for (AddressRange cur_range : ranges) {
if (cur_range.GetByteSize() == 0)
cur_range.SetByteSize(DEFAULT_DISASM_BYTE_SIZE);
if (Disassembler::Disassemble(
GetDebugger(), m_options.arch, plugin_name, flavor_string,
m_exe_ctx, cur_range, m_options.num_instructions,
m_options.show_mixed,
m_options.show_mixed ? m_options.num_lines_context : 0, options,
result.GetOutputStream())) {
result.SetStatus(eReturnStatusSuccessFinishResult);
} else {
result.AppendErrorWithFormat(
"Failed to disassemble memory at 0x%8.8" PRIx64 ".\n",
m_options.start_addr);
result.SetStatus(eReturnStatusFailed);
}
if (print_sc_header)
result.AppendMessage("\n");
}
}
}
return result.Succeeded();
}