181ad6265SDimitry Andric //===- WasmObjcopy.cpp ----------------------------------------------------===//
281ad6265SDimitry Andric //
381ad6265SDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
481ad6265SDimitry Andric // See https://llvm.org/LICENSE.txt for license information.
581ad6265SDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
681ad6265SDimitry Andric //
781ad6265SDimitry Andric //===----------------------------------------------------------------------===//
881ad6265SDimitry Andric
981ad6265SDimitry Andric #include "llvm/ObjCopy/wasm/WasmObjcopy.h"
1081ad6265SDimitry Andric #include "WasmObject.h"
1181ad6265SDimitry Andric #include "WasmReader.h"
1281ad6265SDimitry Andric #include "WasmWriter.h"
1381ad6265SDimitry Andric #include "llvm/ObjCopy/CommonConfig.h"
1481ad6265SDimitry Andric #include "llvm/Support/Errc.h"
1581ad6265SDimitry Andric #include "llvm/Support/FileOutputBuffer.h"
1681ad6265SDimitry Andric
1781ad6265SDimitry Andric namespace llvm {
1881ad6265SDimitry Andric namespace objcopy {
1981ad6265SDimitry Andric namespace wasm {
2081ad6265SDimitry Andric
2181ad6265SDimitry Andric using namespace object;
2281ad6265SDimitry Andric using SectionPred = std::function<bool(const Section &Sec)>;
2381ad6265SDimitry Andric
isDebugSection(const Section & Sec)2481ad6265SDimitry Andric static bool isDebugSection(const Section &Sec) {
25*5f757f3fSDimitry Andric return Sec.Name.starts_with(".debug");
2681ad6265SDimitry Andric }
2781ad6265SDimitry Andric
isLinkerSection(const Section & Sec)2881ad6265SDimitry Andric static bool isLinkerSection(const Section &Sec) {
29*5f757f3fSDimitry Andric return Sec.Name.starts_with("reloc.") || Sec.Name == "linking";
3081ad6265SDimitry Andric }
3181ad6265SDimitry Andric
isNameSection(const Section & Sec)3281ad6265SDimitry Andric static bool isNameSection(const Section &Sec) { return Sec.Name == "name"; }
3381ad6265SDimitry Andric
3481ad6265SDimitry Andric // Sections which are known to be "comments" or informational and do not affect
3581ad6265SDimitry Andric // program semantics.
isCommentSection(const Section & Sec)3681ad6265SDimitry Andric static bool isCommentSection(const Section &Sec) {
3781ad6265SDimitry Andric return Sec.Name == "producers";
3881ad6265SDimitry Andric }
3981ad6265SDimitry Andric
dumpSectionToFile(StringRef SecName,StringRef Filename,Object & Obj)4081ad6265SDimitry Andric static Error dumpSectionToFile(StringRef SecName, StringRef Filename,
4181ad6265SDimitry Andric Object &Obj) {
4281ad6265SDimitry Andric for (const Section &Sec : Obj.Sections) {
4381ad6265SDimitry Andric if (Sec.Name == SecName) {
4481ad6265SDimitry Andric ArrayRef<uint8_t> Contents = Sec.Contents;
4581ad6265SDimitry Andric Expected<std::unique_ptr<FileOutputBuffer>> BufferOrErr =
4681ad6265SDimitry Andric FileOutputBuffer::create(Filename, Contents.size());
4781ad6265SDimitry Andric if (!BufferOrErr)
4881ad6265SDimitry Andric return BufferOrErr.takeError();
4981ad6265SDimitry Andric std::unique_ptr<FileOutputBuffer> Buf = std::move(*BufferOrErr);
5081ad6265SDimitry Andric std::copy(Contents.begin(), Contents.end(), Buf->getBufferStart());
5181ad6265SDimitry Andric if (Error E = Buf->commit())
5281ad6265SDimitry Andric return E;
5381ad6265SDimitry Andric return Error::success();
5481ad6265SDimitry Andric }
5581ad6265SDimitry Andric }
5681ad6265SDimitry Andric return createStringError(errc::invalid_argument, "section '%s' not found",
5781ad6265SDimitry Andric SecName.str().c_str());
5881ad6265SDimitry Andric }
5981ad6265SDimitry Andric
removeSections(const CommonConfig & Config,Object & Obj)6081ad6265SDimitry Andric static void removeSections(const CommonConfig &Config, Object &Obj) {
6181ad6265SDimitry Andric SectionPred RemovePred = [](const Section &) { return false; };
6281ad6265SDimitry Andric
6381ad6265SDimitry Andric // Explicitly-requested sections.
6481ad6265SDimitry Andric if (!Config.ToRemove.empty()) {
6581ad6265SDimitry Andric RemovePred = [&Config](const Section &Sec) {
6681ad6265SDimitry Andric return Config.ToRemove.matches(Sec.Name);
6781ad6265SDimitry Andric };
6881ad6265SDimitry Andric }
6981ad6265SDimitry Andric
7081ad6265SDimitry Andric if (Config.StripDebug) {
7181ad6265SDimitry Andric RemovePred = [RemovePred](const Section &Sec) {
7281ad6265SDimitry Andric return RemovePred(Sec) || isDebugSection(Sec);
7381ad6265SDimitry Andric };
7481ad6265SDimitry Andric }
7581ad6265SDimitry Andric
7681ad6265SDimitry Andric if (Config.StripAll) {
7781ad6265SDimitry Andric RemovePred = [RemovePred](const Section &Sec) {
7881ad6265SDimitry Andric return RemovePred(Sec) || isDebugSection(Sec) || isLinkerSection(Sec) ||
7981ad6265SDimitry Andric isNameSection(Sec) || isCommentSection(Sec);
8081ad6265SDimitry Andric };
8181ad6265SDimitry Andric }
8281ad6265SDimitry Andric
8381ad6265SDimitry Andric if (Config.OnlyKeepDebug) {
8481ad6265SDimitry Andric RemovePred = [&Config](const Section &Sec) {
8581ad6265SDimitry Andric // Keep debug sections, unless explicitly requested to remove.
8681ad6265SDimitry Andric // Remove everything else, including known sections.
8781ad6265SDimitry Andric return Config.ToRemove.matches(Sec.Name) || !isDebugSection(Sec);
8881ad6265SDimitry Andric };
8981ad6265SDimitry Andric }
9081ad6265SDimitry Andric
9181ad6265SDimitry Andric if (!Config.OnlySection.empty()) {
9281ad6265SDimitry Andric RemovePred = [&Config](const Section &Sec) {
9381ad6265SDimitry Andric // Explicitly keep these sections regardless of previous removes.
9481ad6265SDimitry Andric // Remove everything else, inluding known sections.
9581ad6265SDimitry Andric return !Config.OnlySection.matches(Sec.Name);
9681ad6265SDimitry Andric };
9781ad6265SDimitry Andric }
9881ad6265SDimitry Andric
9981ad6265SDimitry Andric if (!Config.KeepSection.empty()) {
10081ad6265SDimitry Andric RemovePred = [&Config, RemovePred](const Section &Sec) {
10181ad6265SDimitry Andric // Explicitly keep these sections regardless of previous removes.
10281ad6265SDimitry Andric if (Config.KeepSection.matches(Sec.Name))
10381ad6265SDimitry Andric return false;
10481ad6265SDimitry Andric // Otherwise defer to RemovePred.
10581ad6265SDimitry Andric return RemovePred(Sec);
10681ad6265SDimitry Andric };
10781ad6265SDimitry Andric }
10881ad6265SDimitry Andric
10981ad6265SDimitry Andric Obj.removeSections(RemovePred);
11081ad6265SDimitry Andric }
11181ad6265SDimitry Andric
handleArgs(const CommonConfig & Config,Object & Obj)11281ad6265SDimitry Andric static Error handleArgs(const CommonConfig &Config, Object &Obj) {
11381ad6265SDimitry Andric // Only support AddSection, DumpSection, RemoveSection for now.
11481ad6265SDimitry Andric for (StringRef Flag : Config.DumpSection) {
11581ad6265SDimitry Andric StringRef SecName;
11681ad6265SDimitry Andric StringRef FileName;
11781ad6265SDimitry Andric std::tie(SecName, FileName) = Flag.split("=");
11881ad6265SDimitry Andric if (Error E = dumpSectionToFile(SecName, FileName, Obj))
11981ad6265SDimitry Andric return createFileError(FileName, std::move(E));
12081ad6265SDimitry Andric }
12181ad6265SDimitry Andric
12281ad6265SDimitry Andric removeSections(Config, Obj);
12381ad6265SDimitry Andric
12481ad6265SDimitry Andric for (const NewSectionInfo &NewSection : Config.AddSection) {
12581ad6265SDimitry Andric Section Sec;
12681ad6265SDimitry Andric Sec.SectionType = llvm::wasm::WASM_SEC_CUSTOM;
12781ad6265SDimitry Andric Sec.Name = NewSection.SectionName;
12881ad6265SDimitry Andric
129bdd1243dSDimitry Andric llvm::StringRef InputData =
130bdd1243dSDimitry Andric llvm::StringRef(NewSection.SectionData->getBufferStart(),
131bdd1243dSDimitry Andric NewSection.SectionData->getBufferSize());
13281ad6265SDimitry Andric std::unique_ptr<MemoryBuffer> BufferCopy = MemoryBuffer::getMemBufferCopy(
133bdd1243dSDimitry Andric InputData, NewSection.SectionData->getBufferIdentifier());
134bdd1243dSDimitry Andric Sec.Contents = ArrayRef<uint8_t>(
13581ad6265SDimitry Andric reinterpret_cast<const uint8_t *>(BufferCopy->getBufferStart()),
13681ad6265SDimitry Andric BufferCopy->getBufferSize());
13781ad6265SDimitry Andric
13881ad6265SDimitry Andric Obj.addSectionWithOwnedContents(Sec, std::move(BufferCopy));
13981ad6265SDimitry Andric }
14081ad6265SDimitry Andric
14181ad6265SDimitry Andric return Error::success();
14281ad6265SDimitry Andric }
14381ad6265SDimitry Andric
executeObjcopyOnBinary(const CommonConfig & Config,const WasmConfig &,object::WasmObjectFile & In,raw_ostream & Out)14481ad6265SDimitry Andric Error executeObjcopyOnBinary(const CommonConfig &Config, const WasmConfig &,
14581ad6265SDimitry Andric object::WasmObjectFile &In, raw_ostream &Out) {
14681ad6265SDimitry Andric Reader TheReader(In);
14781ad6265SDimitry Andric Expected<std::unique_ptr<Object>> ObjOrErr = TheReader.create();
14881ad6265SDimitry Andric if (!ObjOrErr)
14981ad6265SDimitry Andric return createFileError(Config.InputFilename, ObjOrErr.takeError());
15081ad6265SDimitry Andric Object *Obj = ObjOrErr->get();
15181ad6265SDimitry Andric assert(Obj && "Unable to deserialize Wasm object");
15281ad6265SDimitry Andric if (Error E = handleArgs(Config, *Obj))
15381ad6265SDimitry Andric return E;
15481ad6265SDimitry Andric Writer TheWriter(*Obj, Out);
15581ad6265SDimitry Andric if (Error E = TheWriter.write())
15681ad6265SDimitry Andric return createFileError(Config.OutputFilename, std::move(E));
15781ad6265SDimitry Andric return Error::success();
15881ad6265SDimitry Andric }
15981ad6265SDimitry Andric
16081ad6265SDimitry Andric } // end namespace wasm
16181ad6265SDimitry Andric } // end namespace objcopy
16281ad6265SDimitry Andric } // end namespace llvm
163