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[10] Add framework support to LLVM ELF linker (#16)
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Stupid linker tricks, Volume 1
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@mszoek
mszoek committed Mar 13, 2021
1 parent 3218c92 commit 2d0acbf
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11 changes: 10 additions & 1 deletion Makefile
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Expand Up @@ -28,12 +28,21 @@ checkout:
(cd ${TOPDIR} && git clone https://github.com/freebsd/freebsd-src.git && \
cd freebsd-src && git checkout stable/12)

freebsd: checkout ${TOPDIR}/freebsd-src/sys/${MACHINE}/compile/${BSDCONFIG}
patchbsd: patches/*.patch
(cd ${TOPDIR}/freebsd-src && git checkout -f stable/12; \
git branch -D helium/12 || true; \
git checkout -b helium/12; \
for patch in ${TOPDIR}/patches/*.patch; do patch -p1 < $$patch; done)

freebsd: checkout patchbsd ${TOPDIR}/freebsd-src/sys/${MACHINE}/compile/${BSDCONFIG}
export MAKEOBJDIRPREFIX=${MAKEOBJDIRPREFIX}; make -C ${TOPDIR}/freebsd-src buildkernel buildworld

freebsd-noclean:
export MAKEOBJDIRPREFIX=${MAKEOBJDIRPREFIX}; make -C ${TOPDIR}/freebsd-src -DNO_CLEAN buildkernel buildworld

freebsd-usr-noclean:
export MAKEOBJDIRPREFIX=${MAKEOBJDIRPREFIX}; make -C ${TOPDIR}/freebsd-src -DNO_CLEAN buildworld

helium: extradirs mkfiles libobjc2 frameworksclean frameworks copyfiles

# Update the build system with current source
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181 changes: 181 additions & 0 deletions patches/0100_llvm_framework.patch
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@@ -0,0 +1,181 @@
diff --git a/contrib/llvm-project/lld/ELF/Config.h b/contrib/llvm-project/lld/ELF/Config.h
index ef1edbcd1992..bacdcbc3d741 100644
--- a/contrib/llvm-project/lld/ELF/Config.h
+++ b/contrib/llvm-project/lld/ELF/Config.h
@@ -120,6 +120,8 @@ struct Configuration {
std::vector<llvm::StringRef> auxiliaryList;
std::vector<llvm::StringRef> filterList;
std::vector<llvm::StringRef> searchPaths;
+ std::vector<llvm::StringRef> frameworkSearchPaths;
+ std::vector<std::string> frameworkRunPaths;
std::vector<llvm::StringRef> symbolOrderingFile;
std::vector<llvm::StringRef> undefined;
std::vector<SymbolVersion> dynamicList;
diff --git a/contrib/llvm-project/lld/ELF/Driver.cpp b/contrib/llvm-project/lld/ELF/Driver.cpp
index 6de9698bb2c8..31a7e4d702e8 100644
--- a/contrib/llvm-project/lld/ELF/Driver.cpp
+++ b/contrib/llvm-project/lld/ELF/Driver.cpp
@@ -59,6 +59,7 @@
#include "llvm/Support/raw_ostream.h"
#include <cstdlib>
#include <utility>
+#include <unistd.h> // readlink

using namespace llvm;
using namespace llvm::ELF;
@@ -277,6 +278,49 @@ void LinkerDriver::addLibrary(StringRef name) {
error("unable to find library -l" + name);
}

+// Add all libraries within a framework found on the framework search path
+void LinkerDriver::addFramework(StringRef name) {
+ if (Optional<std::string> path = searchFramework(name)) {
+ path->append(llvm::sys::path::get_separator());
+ path->append("Versions");
+ path->append(llvm::sys::path::get_separator());
+
+ std::string rpath(path.getValue());
+
+ path->append("Current");
+ config->searchPaths.push_back(path.getValue());
+
+ char buffer[_POSIX_PATH_MAX];
+ int count = ::readlink(path.getValue().c_str(), buffer, sizeof(buffer));
+ if(count > 0)
+ rpath.append(buffer, buffer + count);
+ else
+ rpath.append("Current");
+
+ // handle frameworks relative to executable (in the app bundle)
+ if(llvm::sys::path::is_relative(Twine(rpath))) {
+ std::string opath("$ORIGIN");
+ opath.append(llvm::sys::path::get_separator());
+ opath.append(rpath);
+ rpath = opath;
+ }
+ config->frameworkRunPaths.push_back(rpath);
+
+ // Now that we've added the current version folder of the framework, find
+ // all the shared libs inside it and add them to the link
+ std::error_code EC;
+ llvm::sys::fs::directory_iterator Dir = llvm::sys::fs::directory_iterator(Twine(path.getValue()), EC, true);
+ llvm::sys::fs::directory_iterator DirEnd;
+ for(Dir; Dir != DirEnd && !EC; Dir.increment(EC)) {
+ if (llvm::sys::path::extension(Dir->path()) != ".so")
+ continue;
+ addFile(Dir->path(), true);
+ }
+ }
+ else
+ error("unable to find framework " + name);
+}
+
// This function is called on startup. We need this for LTO since
// LTO calls LLVM functions to compile bitcode files to native code.
// Technically this can be delayed until we read bitcode files, but
@@ -882,6 +926,7 @@ static void readConfigs(opt::InputArgList &args) {
config->fixCortexA53Errata843419 = args.hasArg(OPT_fix_cortex_a53_843419);
config->fixCortexA8 = args.hasArg(OPT_fix_cortex_a8);
config->forceBTI = hasZOption(args, "force-bti");
+ config->frameworkSearchPaths = args::getStrings(args, OPT_F);
config->gcSections = args.hasFlag(OPT_gc_sections, OPT_no_gc_sections, false);
config->gnuUnique = args.hasFlag(OPT_gnu_unique, OPT_no_gnu_unique, true);
config->gdbIndex = args.hasFlag(OPT_gdb_index, OPT_no_gdb_index, false);
@@ -1185,6 +1230,9 @@ void LinkerDriver::createFiles(opt::InputArgList &args) {
case OPT_library:
addLibrary(arg->getValue());
break;
+ case OPT_framework:
+ addFramework(arg->getValue());
+ break;
case OPT_INPUT:
addFile(arg->getValue(), /*withLOption=*/false);
break;
diff --git a/contrib/llvm-project/lld/ELF/Driver.h b/contrib/llvm-project/lld/ELF/Driver.h
index 3115e28d1669..78ff8948c9d5 100644
--- a/contrib/llvm-project/lld/ELF/Driver.h
+++ b/contrib/llvm-project/lld/ELF/Driver.h
@@ -29,6 +29,7 @@ class LinkerDriver {
void main(ArrayRef<const char *> args);
void addFile(StringRef path, bool withLOption);
void addLibrary(StringRef name);
+ void addFramework(StringRef name);

private:
void createFiles(llvm::opt::InputArgList &args);
@@ -70,6 +71,7 @@ llvm::Optional<std::string> findFromSearchPaths(StringRef path);
llvm::Optional<std::string> searchScript(StringRef path);
llvm::Optional<std::string> searchLibraryBaseName(StringRef path);
llvm::Optional<std::string> searchLibrary(StringRef path);
+llvm::Optional<std::string> searchFramework(StringRef path);

} // namespace elf
} // namespace lld
diff --git a/contrib/llvm-project/lld/ELF/DriverUtils.cpp b/contrib/llvm-project/lld/ELF/DriverUtils.cpp
index 9fcb36e81676..dc29e74a34a0 100644
--- a/contrib/llvm-project/lld/ELF/DriverUtils.cpp
+++ b/contrib/llvm-project/lld/ELF/DriverUtils.cpp
@@ -243,6 +243,14 @@ Optional<std::string> searchLibrary(StringRef name) {
return searchLibraryBaseName(name);
}

+Optional<std::string> searchFramework(StringRef name) {
+ for (StringRef dir : config->frameworkSearchPaths) {
+ if (Optional<std::string> s = findFile(dir, name + ".framework"))
+ return s;
+ }
+ return None;
+}
+
// If a linker/version script doesn't exist in the current directory, we also
// look for the script in the '-L' search paths. This matches the behaviour of
// '-T', --version-script=, and linker script INPUT() command in ld.bfd.
diff --git a/contrib/llvm-project/lld/ELF/Options.td b/contrib/llvm-project/lld/ELF/Options.td
index ea78a3526211..8db62e4b39cd 100644
--- a/contrib/llvm-project/lld/ELF/Options.td
+++ b/contrib/llvm-project/lld/ELF/Options.td
@@ -29,6 +29,14 @@ def Bstatic: F<"Bstatic">, HelpText<"Do not link against shared libraries">;

def build_id: F<"build-id">, HelpText<"Alias for --build-id=fast">;

+def F : JoinedOrSeparate<["-"], "F">,
+ MetaVarName<"<dir>">,
+ HelpText<"Add directory to framework search path">;
+
+def framework : Separate<["-"], "framework">,
+ MetaVarName<"<name>">,
+ HelpText<"Base name of framework searched for in -F directories">;
+
def build_id_eq: J<"build-id=">, HelpText<"Generate build ID note">,
MetaVarName<"[fast,md5,sha1,uuid,0x<hexstring>]">;

@@ -434,7 +442,7 @@ def: Flag<["-"], "q">, Alias<emit_relocs>, HelpText<"Alias for --emit-relocs">;
def: Flag<["-"], ")">, Alias<end_group>, HelpText<"Alias for --end-group">;
def: JoinedOrSeparate<["-"], "e">, Alias<entry>, HelpText<"Alias for --entry">;
def: Flag<["-"], "E">, Alias<export_dynamic>, HelpText<"Alias for --export-dynamic">;
-def: Separate<["-"], "F">, Alias<filter>, HelpText<"Alias for --filter">;
+//def: Separate<["-"], "F">, Alias<filter>, HelpText<"Alias for --filter">;
def: Separate<["-"], "b">, Alias<format>, HelpText<"Alias for --format">;
def: JoinedOrSeparate<["-"], "l">, Alias<library>, HelpText<"Alias for --library">;
def: JoinedOrSeparate<["-"], "L">, Alias<library_path>, HelpText<"Alias for --library-path">;
diff --git a/contrib/llvm-project/lld/ELF/SyntheticSections.cpp b/contrib/llvm-project/lld/ELF/SyntheticSections.cpp
index 67709916cd32..9ba7c52c0000 100644
--- a/contrib/llvm-project/lld/ELF/SyntheticSections.cpp
+++ b/contrib/llvm-project/lld/ELF/SyntheticSections.cpp
@@ -1281,7 +1281,16 @@ template <class ELFT> void DynamicSection<ELFT>::finalizeContents() {
for (StringRef s : config->auxiliaryList)
addInt(DT_AUXILIARY, part.dynStrTab->addString(s));

+ if (!config->frameworkRunPaths.empty()) {
+ std::string s(llvm::join(config->frameworkRunPaths.begin(),config->frameworkRunPaths.end(),":"));
+ if(config->rpath.empty())
+ config->rpath = s;
+ else
+ config->rpath.append(":" + s);
+ }
+
if (!config->rpath.empty())
+ config->frameworkRunPaths.push_back(config->rpath);
addInt(config->enableNewDtags ? DT_RUNPATH : DT_RPATH,
part.dynStrTab->addString(config->rpath));

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