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Change the implementation of --dynamic-list to use linker script parsing. 

The feature is documented as
-----------------------------
The format of the dynamic list is the same as the version node
without scope and node name.  See *note VERSION:: for more
information.
--------------------------------

And indeed qt uses a dynamic list with an 'extern "C++"' in it. With
this patch we support that

The change to gc-sections-shared makes us match bfd. Just because we
kept bar doesn't mean it has to be in the dynamic symbol table.

The changes to invalid-dynamic-list.test and reproduce.s are because
of the new parser.

The changes to version-script.s are the only case where we change
behavior with regards to bfd, but I would like to see a mix of
--version-script and --dynamic-list used in the wild before
complicating the code.

llvm-svn: 289082
This commit is contained in:
Rafael Espindola 2016-12-08 17:54:26 +00:00
parent 6f6d46d497
commit d0ebd84c42
12 changed files with 30 additions and 86 deletions
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1
lld/ELF/Config.h
View File

@ -87,7 +87,6 @@ struct Configuration {
std::string RPath;
std::vector<VersionDefinition> VersionDefinitions;
std::vector<llvm::StringRef> AuxiliaryList;
std::vector<llvm::StringRef> DynamicList;
std::vector<llvm::StringRef> SearchPaths;
std::vector<llvm::StringRef> Undefined;
std::vector<SymbolVersion> VersionScriptGlobals;

15
lld/ELF/Driver.cpp
View File

@ -627,14 +627,24 @@ void LinkerDriver::readConfigs(opt::InputArgList &Args) {
if (auto *Arg = Args.getLastArg(OPT_dynamic_list))
if (Optional<MemoryBufferRef> Buffer = readFile(Arg->getValue()))
parseDynamicList(*Buffer);
readDynamicList(*Buffer);
if (auto *Arg = Args.getLastArg(OPT_symbol_ordering_file))
if (Optional<MemoryBufferRef> Buffer = readFile(Arg->getValue()))
parseSymbolOrderingList(*Buffer);
for (auto *Arg : Args.filtered(OPT_export_dynamic_symbol))
Config->DynamicList.push_back(Arg->getValue());
Config->VersionScriptGlobals.push_back(
{Arg->getValue(), /*IsExternCpp*/ false, /*HasWildcard*/ false});
// Dynamic lists are a simplified linker script that doesn't need the
// "global:" and implicitly ends with a "local:*". Set the variables needed to
// simulate that.
if (Args.hasArg(OPT_dynamic_list) || Args.hasArg(OPT_export_dynamic_symbol)) {
Config->ExportDynamic = true;
if (!Config->Shared)
Config->DefaultSymbolVersion = VER_NDX_LOCAL;
}
if (auto *Arg = Args.getLastArg(OPT_version_script))
if (Optional<MemoryBufferRef> Buffer = readFile(Arg->getValue()))
@ -793,7 +803,6 @@ template <class ELFT> void LinkerDriver::link(opt::InputArgList &Args) {
Symtab.scanUndefinedFlags();
Symtab.scanShlibUndefined();
Symtab.scanDynamicList();
Symtab.scanVersionScript();
Symtab.addCombinedLTOObject();

1
lld/ELF/Driver.h
View File

@ -69,7 +69,6 @@ enum {
void printHelp(const char *Argv0);
std::vector<uint8_t> parseHexstring(StringRef S);
void parseDynamicList(MemoryBufferRef MB);
std::string createResponseFile(const llvm::opt::InputArgList &Args);

26
lld/ELF/DriverUtils.cpp
View File

@ -90,32 +90,6 @@ opt::InputArgList ELFOptTable::parse(ArrayRef<const char *> Argv) {
return Args;
}
// Parse the --dynamic-list argument. A dynamic list is in the form
//
// { symbol1; symbol2; [...]; symbolN };
//
// Multiple groups can be defined in the same file, and they are merged
// into a single group.
void elf::parseDynamicList(MemoryBufferRef MB) {
class Parser : public ScriptParserBase {
public:
Parser(MemoryBufferRef MB) : ScriptParserBase(MB) {}
void run() {
while (!atEOF()) {
expect("{");
while (!Error && !consume("}")) {
Config->DynamicList.push_back(unquote(next()));
expect(";");
}
expect(";");
}
}
};
Parser(MB).run();
}
void elf::printHelp(const char *Argv0) {
ELFOptTable Table;
Table.PrintHelp(outs(), Argv0, "lld", false);

14
lld/ELF/LinkerScript.cpp
View File

@ -987,6 +987,7 @@ public:
void readLinkerScript();
void readVersionScript();
void readDynamicList();
private:
void addFile(StringRef Path);
@ -1040,6 +1041,13 @@ private:
std::vector<std::unique_ptr<MemoryBuffer>> OwningMBs;
};
void ScriptParser::readDynamicList() {
expect("{");
readAnonymousDeclaration();
if (!atEOF())
setError("EOF expected, but got " + next());
}
void ScriptParser::readVersionScript() {
readVersionScriptCommand();
if (!atEOF())
@ -1932,7 +1940,7 @@ std::vector<SymbolVersion> ScriptParser::readVersionExtern() {
StringRef Tok = next();
bool IsCXX = Tok == "\"C++\"";
if (!IsCXX && Tok != "\"C\"")
setError("Unknown Language");
setError("Unknown language");
expect("{");
std::vector<SymbolVersion> Ret;
@ -1956,6 +1964,10 @@ void elf::readVersionScript(MemoryBufferRef MB) {
ScriptParser(MB).readVersionScript();
}
void elf::readDynamicList(MemoryBufferRef MB) {
ScriptParser(MB).readDynamicList();
}
template class elf::LinkerScript<ELF32LE>;
template class elf::LinkerScript<ELF32BE>;
template class elf::LinkerScript<ELF64LE>;

2
lld/ELF/LinkerScript.h
View File

@ -66,6 +66,8 @@ void readLinkerScript(MemoryBufferRef MB);
// Parses a version script.
void readVersionScript(MemoryBufferRef MB);
void readDynamicList(MemoryBufferRef MB);
// This enum is used to implement linker script SECTIONS command.
// https://sourceware.org/binutils/docs/ld/SECTIONS.html#SECTIONS
enum SectionsCommandKind {

7
lld/ELF/SymbolTable.cpp
View File

@ -535,13 +535,6 @@ template <class ELFT> void SymbolTable<ELFT>::scanShlibUndefined() {
Sym->symbol()->ExportDynamic = true;
}
// This function processes --export-dynamic-symbol and --dynamic-list.
template <class ELFT> void SymbolTable<ELFT>::scanDynamicList() {
for (StringRef S : Config->DynamicList)
if (SymbolBody *B = find(S))
B->symbol()->ExportDynamic = true;
}
// Initialize DemangledSyms with a map from demangled symbols to symbol
// objects. Used to handle "extern C++" directive in version scripts.
//

1
lld/ELF/SymbolTable.h
View File

@ -81,7 +81,6 @@ public:
void scanUndefinedFlags();
void scanShlibUndefined();
void scanDynamicList();
void scanVersionScript();
SymbolBody *find(StringRef Name);

9
lld/test/ELF/gc-sections-shared.s
View File

@ -19,15 +19,6 @@
# CHECK-NEXT: Section: Undefined (0x0)
# CHECK-NEXT: }
# CHECK-NEXT: Symbol {
# CHECK-NEXT: Name: bar
# CHECK-NEXT: Value:
# CHECK-NEXT: Size:
# CHECK-NEXT: Binding: Global
# CHECK-NEXT: Type:
# CHECK-NEXT: Other:
# CHECK-NEXT: Section: .text
# CHECK-NEXT: }
# CHECK-NEXT: Symbol {
# CHECK-NEXT: Name: bar2
# CHECK-NEXT: Value:
# CHECK-NEXT: Size:

2
lld/test/ELF/invalid-dynamic-list.test
View File

@ -34,4 +34,4 @@
# RUN: echo "{ extern \"BOGUS\" { test }; };" > %t1
# RUN: not ld.lld --dynamic-list %t1 2>&1 | FileCheck -check-prefix=ERR6 %s
# ERR6: {{.*}}:1: ; expected, but got "BOGUS"
# ERR6: {{.*}}:1: Unknown language

2
lld/test/ELF/reproduce.s
View File

@ -30,7 +30,7 @@
# RUN: diff %t.dir/build2/foo.o repro/%:t.dir/build2/foo.o
# RUN: echo "{ local: *; };" > ver
# RUN: echo > dyn
# RUN: echo "{};" > dyn
# RUN: echo > file
# RUN: echo > file2
# RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o 'foo bar'

36
lld/test/ELF/version-script.s
View File

@ -14,11 +14,6 @@
# RUN: ld.lld --version-script %t3.script -shared %t.o %t2.so -o %t3.so
# RUN: llvm-readobj -dyn-symbols %t3.so | FileCheck --check-prefix=DSO2 %s
# --version-script filters --dynamic-list.
# RUN: echo "{ foo1; foo2; };" > %t.list
# RUN: ld.lld --version-script %t.script --dynamic-list %t.list %t.o %t2.so -o %t
# RUN: llvm-readobj -dyn-symbols %t | FileCheck --check-prefix=EXE %s
# RUN: echo "VERSION_1.0 { global: foo1; local: *; };" > %t4.script
# RUN: echo "VERSION_2.0 { global: foo3; local: *; };" >> %t4.script
# RUN: ld.lld --version-script %t4.script -shared %t.o %t2.so -o %t4.so
@ -42,6 +37,7 @@
# RUN: FileCheck -check-prefix=WARN2 %s
# WARN2: duplicate symbol 'foo1' in version script
# RUN: echo "{ foo1; foo2; };" > %t.list
# RUN: ld.lld --version-script %t.script --dynamic-list %t.list %t.o %t2.so -o %t2
# RUN: llvm-readobj %t2 > /dev/null
@ -105,36 +101,6 @@
# DSO2-NEXT: }
# DSO2-NEXT: ]
# EXE: DynamicSymbols [
# EXE-NEXT: Symbol {
# EXE-NEXT: Name: @
# EXE-NEXT: Value: 0x0
# EXE-NEXT: Size: 0
# EXE-NEXT: Binding: Local (0x0)
# EXE-NEXT: Type: None (0x0)
# EXE-NEXT: Other: 0
# EXE-NEXT: Section: Undefined (0x0)
# EXE-NEXT: }
# EXE-NEXT: Symbol {
# EXE-NEXT: Name: bar@
# EXE-NEXT: Value: 0x0
# EXE-NEXT: Size: 0
# EXE-NEXT: Binding: Global (0x1)
# EXE-NEXT: Type: Function (0x2)
# EXE-NEXT: Other: 0
# EXE-NEXT: Section: Undefined (0x0)
# EXE-NEXT: }
# EXE-NEXT: Symbol {
# EXE-NEXT: Name: foo1@
# EXE-NEXT: Value: 0x201000
# EXE-NEXT: Size: 0
# EXE-NEXT: Binding: Global (0x1)
# EXE-NEXT: Type: None (0x0)
# EXE-NEXT: Other: 0
# EXE-NEXT: Section: .text
# EXE-NEXT: }
# EXE-NEXT: ]
# VERDSO: DynamicSymbols [
# VERDSO-NEXT: Symbol {
# VERDSO-NEXT: Name: @