llvm-project/llvm/lib/Object/SymbolSize.cpp

107 lines
3.4 KiB
C++

//===- SymbolSize.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 "llvm/Object/SymbolSize.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/Object/COFF.h"
#include "llvm/Object/ELFObjectFile.h"
#include "llvm/Object/MachO.h"
#include "llvm/Object/Wasm.h"
using namespace llvm;
using namespace object;
// Orders increasingly by (SectionID, Address).
int llvm::object::compareAddress(const SymEntry *A, const SymEntry *B) {
if (A->SectionID != B->SectionID)
return A->SectionID < B->SectionID ? -1 : 1;
if (A->Address != B->Address)
return A->Address < B->Address ? -1 : 1;
return 0;
}
static unsigned getSectionID(const ObjectFile &O, SectionRef Sec) {
if (auto *M = dyn_cast<MachOObjectFile>(&O))
return M->getSectionID(Sec);
if (isa<WasmObjectFile>(&O))
return Sec.getIndex();
return cast<COFFObjectFile>(O).getSectionID(Sec);
}
static unsigned getSymbolSectionID(const ObjectFile &O, SymbolRef Sym) {
if (auto *M = dyn_cast<MachOObjectFile>(&O))
return M->getSymbolSectionID(Sym);
if (const auto *M = dyn_cast<WasmObjectFile>(&O))
return M->getSymbolSectionId(Sym);
return cast<COFFObjectFile>(O).getSymbolSectionID(Sym);
}
std::vector<std::pair<SymbolRef, uint64_t>>
llvm::object::computeSymbolSizes(const ObjectFile &O) {
std::vector<std::pair<SymbolRef, uint64_t>> Ret;
if (const auto *E = dyn_cast<ELFObjectFileBase>(&O)) {
auto Syms = E->symbols();
if (Syms.begin() == Syms.end())
Syms = E->getDynamicSymbolIterators();
for (ELFSymbolRef Sym : Syms)
Ret.push_back({Sym, Sym.getSize()});
return Ret;
}
// Collect sorted symbol addresses. Include dummy addresses for the end
// of each section.
std::vector<SymEntry> Addresses;
unsigned SymNum = 0;
for (symbol_iterator I = O.symbol_begin(), E = O.symbol_end(); I != E; ++I) {
SymbolRef Sym = *I;
Expected<uint64_t> ValueOrErr = Sym.getValue();
if (!ValueOrErr)
// TODO: Actually report errors helpfully.
report_fatal_error(ValueOrErr.takeError());
Addresses.push_back({I, *ValueOrErr, SymNum, getSymbolSectionID(O, Sym)});
++SymNum;
}
for (SectionRef Sec : O.sections()) {
uint64_t Address = Sec.getAddress();
uint64_t Size = Sec.getSize();
Addresses.push_back(
{O.symbol_end(), Address + Size, 0, getSectionID(O, Sec)});
}
if (Addresses.empty())
return Ret;
array_pod_sort(Addresses.begin(), Addresses.end(), compareAddress);
// Compute the size as the gap to the next symbol
for (unsigned I = 0, N = Addresses.size() - 1; I < N; ++I) {
auto &P = Addresses[I];
if (P.I == O.symbol_end())
continue;
// If multiple symbol have the same address, give both the same size.
unsigned NextI = I + 1;
while (NextI < N && Addresses[NextI].Address == P.Address)
++NextI;
uint64_t Size = Addresses[NextI].Address - P.Address;
P.Address = Size;
}
// Assign the sorted symbols in the original order.
Ret.resize(SymNum);
for (SymEntry &P : Addresses) {
if (P.I == O.symbol_end())
continue;
Ret[P.Number] = {*P.I, P.Address};
}
return Ret;
}