Re-apply r299168 and r299169 now that the libdeps are fixed.
llvm-svn: 299184
diff --git a/llvm/lib/Object/IRSymtab.cpp b/llvm/lib/Object/IRSymtab.cpp
new file mode 100644
index 0000000..1ef2c4b
--- /dev/null
+++ b/llvm/lib/Object/IRSymtab.cpp
@@ -0,0 +1,228 @@
+//===- IRSymtab.cpp - implementation of IR symbol tables --------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Object/IRSymtab.h"
+#include "llvm/Analysis/ObjectUtils.h"
+#include "llvm/IR/Mangler.h"
+#include "llvm/IR/Module.h"
+#include "llvm/MC/StringTableBuilder.h"
+#include "llvm/Object/ModuleSymbolTable.h"
+#include "llvm/Support/Allocator.h"
+#include "llvm/Support/StringSaver.h"
+
+using namespace llvm;
+using namespace irsymtab;
+
+namespace {
+
+/// Stores the temporary state that is required to build an IR symbol table.
+struct Builder {
+ SmallVector<char, 0> &Symtab;
+ SmallVector<char, 0> &Strtab;
+ Builder(SmallVector<char, 0> &Symtab, SmallVector<char, 0> &Strtab)
+ : Symtab(Symtab), Strtab(Strtab) {}
+
+ StringTableBuilder StrtabBuilder{StringTableBuilder::ELF};
+
+ BumpPtrAllocator Alloc;
+ StringSaver Saver{Alloc};
+
+ DenseMap<const Comdat *, unsigned> ComdatMap;
+ ModuleSymbolTable Msymtab;
+ SmallPtrSet<GlobalValue *, 8> Used;
+ Mangler Mang;
+ Triple TT;
+
+ std::vector<storage::Comdat> Comdats;
+ std::vector<storage::Module> Mods;
+ std::vector<storage::Symbol> Syms;
+ std::vector<storage::Uncommon> Uncommons;
+
+ std::string COFFLinkerOpts;
+ raw_string_ostream COFFLinkerOptsOS{COFFLinkerOpts};
+
+ void setStr(storage::Str &S, StringRef Value) {
+ S.Offset = StrtabBuilder.add(Value);
+ }
+ template <typename T>
+ void writeRange(storage::Range<T> &R, const std::vector<T> &Objs) {
+ R.Offset = Symtab.size();
+ R.Size = Objs.size();
+ Symtab.insert(Symtab.end(), reinterpret_cast<const char *>(Objs.data()),
+ reinterpret_cast<const char *>(Objs.data() + Objs.size()));
+ }
+
+ Error addModule(Module *M);
+ Error addSymbol(ModuleSymbolTable::Symbol Sym);
+
+ Error build(ArrayRef<Module *> Mods);
+};
+
+Error Builder::addModule(Module *M) {
+ collectUsedGlobalVariables(*M, Used, /*CompilerUsed*/ false);
+
+ storage::Module Mod;
+ Mod.Begin = Msymtab.symbols().size();
+ Msymtab.addModule(M);
+ Mod.End = Msymtab.symbols().size();
+ Mods.push_back(Mod);
+
+ if (TT.isOSBinFormatCOFF()) {
+ if (auto E = M->materializeMetadata())
+ return E;
+ if (Metadata *Val = M->getModuleFlag("Linker Options")) {
+ MDNode *LinkerOptions = cast<MDNode>(Val);
+ for (const MDOperand &MDOptions : LinkerOptions->operands())
+ for (const MDOperand &MDOption : cast<MDNode>(MDOptions)->operands())
+ COFFLinkerOptsOS << " " << cast<MDString>(MDOption)->getString();
+ }
+ }
+
+ return Error::success();
+}
+
+Error Builder::addSymbol(ModuleSymbolTable::Symbol Msym) {
+ Syms.emplace_back();
+ storage::Symbol &Sym = Syms.back();
+ Sym = {};
+
+ Sym.UncommonIndex = -1;
+ storage::Uncommon *Unc = nullptr;
+ auto Uncommon = [&]() -> storage::Uncommon & {
+ if (Unc)
+ return *Unc;
+ Sym.UncommonIndex = Uncommons.size();
+ Uncommons.emplace_back();
+ Unc = &Uncommons.back();
+ *Unc = {};
+ setStr(Unc->COFFWeakExternFallbackName, "");
+ return *Unc;
+ };
+
+ SmallString<64> Name;
+ {
+ raw_svector_ostream OS(Name);
+ Msymtab.printSymbolName(OS, Msym);
+ }
+ setStr(Sym.Name, Saver.save(StringRef(Name)));
+
+ auto Flags = Msymtab.getSymbolFlags(Msym);
+ if (Flags & object::BasicSymbolRef::SF_Undefined)
+ Sym.Flags |= 1 << storage::Symbol::FB_undefined;
+ if (Flags & object::BasicSymbolRef::SF_Weak)
+ Sym.Flags |= 1 << storage::Symbol::FB_weak;
+ if (Flags & object::BasicSymbolRef::SF_Common)
+ Sym.Flags |= 1 << storage::Symbol::FB_common;
+ if (Flags & object::BasicSymbolRef::SF_Indirect)
+ Sym.Flags |= 1 << storage::Symbol::FB_indirect;
+ if (Flags & object::BasicSymbolRef::SF_Global)
+ Sym.Flags |= 1 << storage::Symbol::FB_global;
+ if (Flags & object::BasicSymbolRef::SF_FormatSpecific)
+ Sym.Flags |= 1 << storage::Symbol::FB_format_specific;
+
+ Sym.ComdatIndex = -1;
+ auto *GV = Msym.dyn_cast<GlobalValue *>();
+ if (!GV) {
+ setStr(Sym.IRName, "");
+ return Error::success();
+ }
+
+ setStr(Sym.IRName, GV->getName());
+
+ if (Used.count(GV))
+ Sym.Flags |= 1 << storage::Symbol::FB_used;
+ if (GV->isThreadLocal())
+ Sym.Flags |= 1 << storage::Symbol::FB_tls;
+ if (GV->hasGlobalUnnamedAddr())
+ Sym.Flags |= 1 << storage::Symbol::FB_unnamed_addr;
+ if (canBeOmittedFromSymbolTable(GV))
+ Sym.Flags |= 1 << storage::Symbol::FB_may_omit;
+ Sym.Flags |= unsigned(GV->getVisibility()) << storage::Symbol::FB_visibility;
+
+ if (Flags & object::BasicSymbolRef::SF_Common) {
+ Uncommon().CommonSize = GV->getParent()->getDataLayout().getTypeAllocSize(
+ GV->getType()->getElementType());
+ Uncommon().CommonAlign = GV->getAlignment();
+ }
+
+ const GlobalObject *Base = GV->getBaseObject();
+ if (!Base)
+ return make_error<StringError>("Unable to determine comdat of alias!",
+ inconvertibleErrorCode());
+ if (const Comdat *C = Base->getComdat()) {
+ auto P = ComdatMap.insert(std::make_pair(C, Comdats.size()));
+ Sym.ComdatIndex = P.first->second;
+
+ if (P.second) {
+ storage::Comdat Comdat;
+ setStr(Comdat.Name, C->getName());
+ Comdats.push_back(Comdat);
+ }
+ }
+
+ if (TT.isOSBinFormatCOFF()) {
+ emitLinkerFlagsForGlobalCOFF(COFFLinkerOptsOS, GV, TT, Mang);
+
+ if ((Flags & object::BasicSymbolRef::SF_Weak) &&
+ (Flags & object::BasicSymbolRef::SF_Indirect)) {
+ std::string FallbackName;
+ raw_string_ostream OS(FallbackName);
+ Msymtab.printSymbolName(
+ OS, cast<GlobalValue>(
+ cast<GlobalAlias>(GV)->getAliasee()->stripPointerCasts()));
+ OS.flush();
+ setStr(Uncommon().COFFWeakExternFallbackName, Saver.save(FallbackName));
+ }
+ }
+
+ return Error::success();
+}
+
+Error Builder::build(ArrayRef<Module *> IRMods) {
+ storage::Header Hdr;
+
+ assert(!IRMods.empty());
+ setStr(Hdr.SourceFileName, IRMods[0]->getSourceFileName());
+ TT = Triple(IRMods[0]->getTargetTriple());
+
+ // This adds the symbols for each module to Msymtab.
+ for (auto *M : IRMods)
+ if (Error Err = addModule(M))
+ return Err;
+
+ for (ModuleSymbolTable::Symbol Msym : Msymtab.symbols())
+ if (Error Err = addSymbol(Msym))
+ return Err;
+
+ COFFLinkerOptsOS.flush();
+ setStr(Hdr.COFFLinkerOpts, COFFLinkerOpts);
+
+ // We are about to fill in the header's range fields, so reserve space for it
+ // and copy it in afterwards.
+ Symtab.resize(sizeof(storage::Header));
+ writeRange(Hdr.Modules, Mods);
+ writeRange(Hdr.Comdats, Comdats);
+ writeRange(Hdr.Symbols, Syms);
+ writeRange(Hdr.Uncommons, Uncommons);
+
+ *reinterpret_cast<storage::Header *>(Symtab.data()) = Hdr;
+
+ raw_svector_ostream OS(Strtab);
+ StrtabBuilder.finalizeInOrder();
+ StrtabBuilder.write(OS);
+
+ return Error::success();
+}
+
+} // anonymous namespace
+
+Error irsymtab::build(ArrayRef<Module *> Mods, SmallVector<char, 0> &Symtab,
+ SmallVector<char, 0> &Strtab) {
+ return Builder(Symtab, Strtab).build(Mods);
+}