87 lines · cpp
1//===-- CoreFileMemoryRanges.cpp --------------------------------*- C++ -*-===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#include "lldb/Target/CoreFileMemoryRanges.h"10 11using namespace lldb;12using namespace lldb_private;13 14using Entry = CoreFileMemoryRanges::Entry;15 16static bool Overlaps(const Entry *region_one, const Entry *region_two) {17 return !(region_one->GetRangeEnd() < region_two->GetRangeBase() ||18 region_two->GetRangeEnd() < region_one->GetRangeBase());19}20 21static bool IntersectHelper(const Entry *region_one, const Entry *region_two) {22 return region_one->GetRangeBase() == region_two->GetRangeEnd() ||23 region_one->GetRangeEnd() == region_two->GetRangeBase();24}25 26static bool OnlyIntersects(const Entry *region_one, const Entry *region_two) {27 return IntersectHelper(region_one, region_two) ||28 IntersectHelper(region_two, region_one);29}30 31static bool PermissionsMatch(const Entry *region_one, const Entry *region_two) {32 return region_one->data.lldb_permissions == region_two->data.lldb_permissions;33}34 35// This assumes any overlapping ranges will share the same permissions36// and that adjacent ranges could have different permissions.37Status CoreFileMemoryRanges::FinalizeCoreFileSaveRanges() {38 Status error;39 this->Sort();40 for (size_t i = this->GetSize() - 1; i > 0; i--) {41 auto region_one = this->GetMutableEntryAtIndex(i);42 auto region_two = this->GetMutableEntryAtIndex(i - 1);43 if (Overlaps(region_one, region_two)) {44 // It's okay for interesecting regions to have different permissions but45 // if they overlap we fail because we don't know what to do with them.46 if (!PermissionsMatch(region_one, region_two)) {47 // Permissions mismatch and it's not a simple intersection.48 if (!OnlyIntersects(region_one, region_two)) {49 error = Status::FromErrorStringWithFormatv(50 "Memory region at {0}::{1} has different permssions than "51 "overlapping region at {2}::{3}",52 region_one->GetRangeBase(), region_one->GetRangeEnd(),53 region_two->GetRangeBase(), region_two->GetRangeEnd());54 return error;55 }56 // Simple intersection, we can just not merge these.57 else58 continue;59 }60 const addr_t base =61 std::min(region_one->GetRangeBase(), region_two->GetRangeBase());62 const addr_t byte_size =63 std::max(region_one->GetRangeEnd(), region_two->GetRangeEnd()) - base;64 65 region_two->SetRangeBase(base);66 region_two->SetByteSize(byte_size);67 68 // Because this is a range data vector, the entry has a base as well69 // as the data contained in the entry. So we have to update both.70 // And llvm::AddressRange isn't mutable so we have to create a new one.71 llvm::AddressRange range(base, base + byte_size);72 const CoreFileMemoryRange core_range = {73 range, region_two->data.lldb_permissions};74 region_two->data = core_range;75 // Erase is delete from [Inclusive, exclusive index).76 if (!this->Erase(i, i + 1)) {77 error = Status::FromErrorStringWithFormat(78 "Core file memory ranges mutated outside of "79 "CalculateCoreFileSaveRanges");80 return error;81 }82 }83 }84 85 return error;86}87