[WebAssembly] Merge producers section
Reviewers: sbc100, aheejin, dschuff
Subscribers: jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D56807
llvm-svn: 351400
diff --git a/lld/wasm/Writer.cpp b/lld/wasm/Writer.cpp
index 819d429..ea65bc3 100644
--- a/lld/wasm/Writer.cpp
+++ b/lld/wasm/Writer.cpp
@@ -21,6 +21,8 @@
#include "lld/Common/Strings.h"
#include "lld/Common/Threads.h"
#include "llvm/ADT/DenseSet.h"
+#include "llvm/ADT/SmallSet.h"
+#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/BinaryFormat/Wasm.h"
#include "llvm/Object/WasmTraits.h"
@@ -95,6 +97,7 @@
void createRelocSections();
void createLinkingSection();
void createNameSection();
+ void createProducersSection();
void writeHeader();
void writeSections();
@@ -327,7 +330,8 @@
StringRef Name = Section->getName();
// These custom sections are known the linker and synthesized rather than
// blindly copied
- if (Name == "linking" || Name == "name" || Name.startswith("reloc."))
+ if (Name == "linking" || Name == "name" || Name == "producers" ||
+ Name.startswith("reloc."))
continue;
// .. or it is a debug section
if (StripDebug && Name.startswith(".debug_"))
@@ -633,6 +637,43 @@
Sub.writeTo(Section->getStream());
}
+void Writer::createProducersSection() {
+ SmallVector<std::pair<std::string, std::string>, 8> Languages;
+ SmallVector<std::pair<std::string, std::string>, 8> Tools;
+ SmallVector<std::pair<std::string, std::string>, 8> SDKs;
+ for (ObjFile *File : Symtab->ObjectFiles) {
+ const WasmProducerInfo &Info = File->getWasmObj()->getProducerInfo();
+ for (auto &Producers : {std::make_pair(&Info.Languages, &Languages),
+ std::make_pair(&Info.Tools, &Tools),
+ std::make_pair(&Info.SDKs, &SDKs)}) {
+ llvm::SmallSet<StringRef, 8> SeenProducers;
+ for (auto &Producer : *Producers.first)
+ if (SeenProducers.insert(Producer.first).second)
+ Producers.second->push_back(Producer);
+ }
+ }
+ int FieldCount =
+ int(!Languages.empty()) + int(!Tools.empty()) + int(!SDKs.empty());
+ if (FieldCount == 0)
+ return;
+ SyntheticSection *Section =
+ createSyntheticSection(WASM_SEC_CUSTOM, "producers");
+ auto &OS = Section->getStream();
+ writeUleb128(OS, FieldCount, "field count");
+ for (auto &Field : {std::make_pair(StringRef("language"), Languages),
+ std::make_pair(StringRef("processed-by"), Tools),
+ std::make_pair(StringRef("sdk"), SDKs)}) {
+ if (Field.second.empty())
+ continue;
+ writeStr(OS, Field.first, "field name");
+ writeUleb128(OS, Field.second.size(), "number of entries");
+ for (auto &Entry : Field.second) {
+ writeStr(OS, Entry.first, "producer name");
+ writeStr(OS, Entry.second, "producer version");
+ }
+ }
+}
+
void Writer::writeHeader() {
memcpy(Buffer->getBufferStart(), Header.data(), Header.size());
}
@@ -772,9 +813,13 @@
createLinkingSection();
createRelocSections();
}
+
if (!Config->StripDebug && !Config->StripAll)
createNameSection();
+ if (!Config->StripAll)
+ createProducersSection();
+
for (OutputSection *S : OutputSections) {
S->setOffset(FileSize);
S->finalizeContents();