llvm-project/lldb/tools/lldb-dap/Handler/BreakpointLocationsHandler.cpp
Ely Ronnen e972d8cbbf
[lldb-dap] assembly breakpoints (#139969)
* Support assembly source breakpoints
* Change `sourceReference` to be the symbol load address for simplicity
and consistency across threads/frames

[Screencast From 2025-05-17
23-57-30.webm](https://github.com/user-attachments/assets/2e7c181d-42c1-4121-8f13-b180c19d0e33)
2025-05-21 21:13:32 +02:00

130 lines
4.9 KiB
C++

//===-- BreakpointLocationsHandler..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 "DAP.h"
#include "RequestHandler.h"
#include <optional>
#include <vector>
namespace lldb_dap {
/// The `breakpointLocations` request returns all possible locations for source
/// breakpoints in a given range. Clients should only call this request if the
/// corresponding capability `supportsBreakpointLocationsRequest` is true.
llvm::Expected<protocol::BreakpointLocationsResponseBody>
BreakpointLocationsRequestHandler::Run(
const protocol::BreakpointLocationsArguments &args) const {
uint32_t start_line = args.line;
uint32_t start_column = args.column.value_or(LLDB_INVALID_COLUMN_NUMBER);
uint32_t end_line = args.endLine.value_or(start_line);
uint32_t end_column =
args.endColumn.value_or(std::numeric_limits<uint32_t>::max());
// Find all relevant lines & columns.
std::vector<std::pair<uint32_t, uint32_t>> locations;
if (args.source.sourceReference) {
locations = GetAssemblyBreakpointLocations(*args.source.sourceReference,
start_line, end_line);
} else {
std::string path = args.source.path.value_or("");
locations = GetSourceBreakpointLocations(
std::move(path), start_line, start_column, end_line, end_column);
}
// The line entries are sorted by addresses, but we must return the list
// ordered by line / column position.
std::sort(locations.begin(), locations.end());
locations.erase(llvm::unique(locations), locations.end());
std::vector<protocol::BreakpointLocation> breakpoint_locations;
for (auto &l : locations)
breakpoint_locations.push_back(
{l.first, l.second, std::nullopt, std::nullopt});
return protocol::BreakpointLocationsResponseBody{
/*breakpoints=*/std::move(breakpoint_locations)};
}
std::vector<std::pair<uint32_t, uint32_t>>
BreakpointLocationsRequestHandler::GetSourceBreakpointLocations(
std::string path, uint32_t start_line, uint32_t start_column,
uint32_t end_line, uint32_t end_column) const {
std::vector<std::pair<uint32_t, uint32_t>> locations;
lldb::SBFileSpec file_spec(path.c_str(), true);
lldb::SBSymbolContextList compile_units =
dap.target.FindCompileUnits(file_spec);
for (uint32_t c_idx = 0, c_limit = compile_units.GetSize(); c_idx < c_limit;
++c_idx) {
const lldb::SBCompileUnit &compile_unit =
compile_units.GetContextAtIndex(c_idx).GetCompileUnit();
if (!compile_unit.IsValid())
continue;
lldb::SBFileSpec primary_file_spec = compile_unit.GetFileSpec();
// Go through the line table and find all matching lines / columns
for (uint32_t l_idx = 0, l_limit = compile_unit.GetNumLineEntries();
l_idx < l_limit; ++l_idx) {
lldb::SBLineEntry line_entry = compile_unit.GetLineEntryAtIndex(l_idx);
// Filter by line / column
uint32_t line = line_entry.GetLine();
if (line < start_line || line > end_line)
continue;
uint32_t column = line_entry.GetColumn();
if (column == LLDB_INVALID_COLUMN_NUMBER)
continue;
if (line == start_line && column < start_column)
continue;
if (line == end_line && column > end_column)
continue;
// Make sure we are in the right file.
// We might have a match on line & column range and still
// be in the wrong file, e.g. for included files.
// Given that the involved pointers point into LLDB's string pool,
// we can directly compare the `const char*` pointers.
if (line_entry.GetFileSpec().GetFilename() !=
primary_file_spec.GetFilename() ||
line_entry.GetFileSpec().GetDirectory() !=
primary_file_spec.GetDirectory())
continue;
locations.emplace_back(line, column);
}
}
return locations;
}
std::vector<std::pair<uint32_t, uint32_t>>
BreakpointLocationsRequestHandler::GetAssemblyBreakpointLocations(
int64_t source_reference, uint32_t start_line, uint32_t end_line) const {
std::vector<std::pair<uint32_t, uint32_t>> locations;
lldb::SBAddress address(source_reference, dap.target);
if (!address.IsValid())
return locations;
lldb::SBSymbol symbol = address.GetSymbol();
if (!symbol.IsValid())
return locations;
// start_line is relative to the symbol's start address.
lldb::SBInstructionList insts = symbol.GetInstructions(dap.target);
if (insts.GetSize() > (start_line - 1))
locations.reserve(insts.GetSize() - (start_line - 1));
for (uint32_t i = start_line - 1; i < insts.GetSize() && i <= (end_line - 1);
++i) {
locations.emplace_back(i, 1);
}
return locations;
}
} // namespace lldb_dap