llvm/lldb/source/Breakpoint/WatchpointAlgorithms.cpp

//===-- WatchpointAlgorithms.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 "lldb/Breakpoint/WatchpointAlgorithms.h"
#include "lldb/Breakpoint/WatchpointResource.h"
#include "lldb/Target/Process.h"
#include "lldb/Utility/ArchSpec.h"
#include "lldb/Utility/LLDBLog.h"
#include "lldb/Utility/Log.h"

#include <algorithm>
#include <utility>
#include <vector>

usingnamespacelldb;
usingnamespacelldb_private;

std::vector<WatchpointResourceSP>
WatchpointAlgorithms::AtomizeWatchpointRequest(
    addr_t addr, size_t size, bool read, bool write,
    WatchpointHardwareFeature supported_features, ArchSpec &arch) { … }

// This should be `std::bit_ceil(aligned_size)` but
// that requires C++20.
// Calculates the smallest integral power of two that is not smaller than x.
static uint64_t bit_ceil(uint64_t input) { … }

/// Convert a user's watchpoint request (\a user_addr and \a user_size)
/// into hardware watchpoints, for a target that can watch a power-of-2
/// region of memory (1, 2, 4, 8, etc), aligned to that same power-of-2
/// memory address.
///
/// If a user asks to watch 4 bytes at address 0x1002 (0x1002-0x1005
/// inclusive) we can implement this with two 2-byte watchpoints
/// (0x1002 and 0x1004) or with an 8-byte watchpoint at 0x1000.
/// A 4-byte watchpoint at 0x1002 would not be properly 4 byte aligned.
///
/// If a user asks to watch 16 bytes at 0x1000, and this target supports
/// 8-byte watchpoints, we can implement this with two 8-byte watchpoints
/// at 0x1000 and 0x1008.
std::vector<WatchpointAlgorithms::Region>
WatchpointAlgorithms::PowerOf2Watchpoints(addr_t user_addr, size_t user_size,
                                          size_t min_byte_size,
                                          size_t max_byte_size,
                                          uint32_t address_byte_size) { … }