jhuber6 created this revision.
jhuber6 added reviewers: jdoerfert, ronlieb, gregrodgers, JonChesterfield.
Herald added subscribers: ormris, dang, steven_wu, guansong, hiraditya, yaxunl.
jhuber6 requested review of this revision.
Herald added subscribers: llvm-commits, cfe-commits, sstefan1.
Herald added projects: clang, LLVM.
Summary;
This patch adds support for embedding device images via the
`fopenmp-target-jit` command to be used for JIT compilation. This is
used in conjunction with `-foffload-lto` to do bitcode linking and
embedding of the device image in the final executable rather than
creating an exectuable. This will be used for JIT in the future.
Depends on D117048 <https://reviews.llvm.org/D117048>
Repository:
rG LLVM Github Monorepo
https://reviews.llvm.org/D117049
Files:
clang/include/clang/Basic/DiagnosticDriverKinds.td
clang/include/clang/Driver/Options.td
clang/lib/Driver/ToolChains/Clang.cpp
clang/tools/clang-linker-wrapper/ClangLinkerWrapper.cpp
llvm/include/llvm/LTO/LTO.h
llvm/lib/LTO/LTO.cpp
Index: llvm/lib/LTO/LTO.cpp
===================================================================
--- llvm/lib/LTO/LTO.cpp
+++ llvm/lib/LTO/LTO.cpp
@@ -958,6 +958,8 @@
return RegularLTO.ParallelCodeGenParallelismLevel + ModuleCount;
}
+Config <O::getLTOConfig() { return Conf; }
+
// If only some of the modules were split, we cannot correctly handle
// code that contains type tests or type checked loads.
Error LTO::checkPartiallySplit() {
Index: llvm/include/llvm/LTO/LTO.h
===================================================================
--- llvm/include/llvm/LTO/LTO.h
+++ llvm/include/llvm/LTO/LTO.h
@@ -259,6 +259,9 @@
/// full description of tasks see LTOBackend.h.
unsigned getMaxTasks() const;
+ /// Returns the current configuration for the LTO object.
+ Config &getLTOConfig();
+
/// Runs the LTO pipeline. This function calls the supplied AddStream
/// function to add native object files to the link.
///
Index: clang/tools/clang-linker-wrapper/ClangLinkerWrapper.cpp
===================================================================
--- clang/tools/clang-linker-wrapper/ClangLinkerWrapper.cpp
+++ clang/tools/clang-linker-wrapper/ClangLinkerWrapper.cpp
@@ -76,6 +76,11 @@
cl::desc("Path for the target bitcode library"),
cl::cat(ClangLinkerWrapperCategory));
+static cl::opt<bool> EmbedBC(
+ "target-embed-bc", cl::ZeroOrMore,
+ cl::desc("Embed linked bitcode instead of an executable device image."),
+ cl::init(true), cl::cat(ClangLinkerWrapperCategory));
+
// Do not parse linker options.
static cl::list<std::string>
HostLinkerArgs(cl::Sink, cl::desc("<options to be passed to linker>..."));
@@ -422,8 +427,8 @@
std::unique_ptr<MemoryBuffer> Buffer =
MemoryBuffer::getMemBuffer(Library.getMemoryBufferRef(), false);
- if (Error Err = writeArchive(TempFile, Members, true, Library.kind(),
- true, Library.isThin(), std::move(Buffer)))
+ if (Error Err = writeArchive(TempFile, Members, true, Library.kind(), true,
+ Library.isThin(), std::move(Buffer)))
return std::move(Err);
return static_cast<std::string>(TempFile);
@@ -748,6 +753,12 @@
return std::move(Err);
}
+ auto HandleError = [&](std::error_code EC) {
+ logAllUnhandledErrors(errorCodeToError(EC),
+ WithColor::error(errs(), LinkerExecutable));
+ exit(1);
+ };
+
// Run the LTO job to compile the bitcode.
size_t MaxTasks = LTOBackend->getMaxTasks();
std::vector<SmallString<128>> Files(MaxTasks);
@@ -757,16 +768,36 @@
StringRef Extension = (TheTriple.isNVPTX()) ? "s" : "o";
if (std::error_code EC = sys::fs::createTemporaryFile(
"lto-" + TheTriple.getTriple(), Extension, FD, TempFile))
- return nullptr;
+ HandleError(EC);
TempFiles.push_back(static_cast<std::string>(TempFile));
return std::make_unique<CachedFileStream>(
std::make_unique<llvm::raw_fd_ostream>(FD, true));
};
+ auto LinkOnly = [&](size_t Task, const Module &M) {
+ int FD = -1;
+ Files.resize(1);
+ auto &TempFile = Files.front();
+ if (std::error_code EC = sys::fs::createTemporaryFile(
+ "jit-" + TheTriple.getTriple(), "bc", FD, TempFile))
+ HandleError(EC);
+ std::error_code EC;
+ raw_fd_ostream LinkedBitcode(TempFile, EC, sys::fs::OF_None);
+ if (EC)
+ HandleError(EC);
+ WriteBitcodeToFile(M, LinkedBitcode);
+ TempFiles.push_back(static_cast<std::string>(TempFile));
+ return false;
+ };
+
+ // If we are doing JIT, stop after the module has been sompletely linked.
+ if (EmbedBC)
+ LTOBackend->getLTOConfig().PostInternalizeModuleHook = LinkOnly;
+
if (Error Err = LTOBackend->run(AddStream))
return std::move(Err);
for (auto &File : Files) {
- if (!TheTriple.isNVPTX())
+ if (!TheTriple.isNVPTX() || EmbedBC)
continue;
auto FileOrErr = nvptx::assemble(File, TheTriple, Arch);
@@ -794,11 +825,16 @@
Triple TheTriple(TargetFeatures.first);
StringRef Arch(TargetFeatures.second);
- // TODO: Run LTO or bitcode linking before the final link job.
auto ObjectOrErr =
linkBitcodeFiles(LinkerInput.getValue(), TheTriple, Arch);
if (!ObjectOrErr)
return ObjectOrErr.takeError();
+
+ if (EmbedBC) {
+ LinkedImages.push_back(**ObjectOrErr);
+ continue;
+ }
+
if ((*ObjectOrErr).hasValue())
LinkerInput.getValue() = {**ObjectOrErr};
Index: clang/lib/Driver/ToolChains/Clang.cpp
===================================================================
--- clang/lib/Driver/ToolChains/Clang.cpp
+++ clang/lib/Driver/ToolChains/Clang.cpp
@@ -8133,6 +8133,12 @@
const char *LinkingOutput) const {
ArgStringList CmdArgs;
+ if (!C.getDriver().isUsingLTO(/* IsOffload */ true) &&
+ Args.hasFlag(options::OPT_fopenmp_target_jit,
+ options::OPT_fno_openmp_target_jit, /*Default*/ false)) {
+ C.getDriver().Diag(clang::diag::err_drv_openmp_jit_without_lto);
+ }
+
if (getToolChain().getDriver().isUsingLTO(/* IsOffload */ true)) {
// Pass in target features for each toolchain.
auto OpenMPTCRange = C.getOffloadToolChains<Action::OFK_OpenMP>();
@@ -8192,6 +8198,11 @@
if (!OOpt.empty())
CmdArgs.push_back(Args.MakeArgString(Twine("-opt-level=O") + OOpt));
}
+
+ if (Args.hasFlag(options::OPT_fopenmp_target_jit,
+ options::OPT_fno_openmp_target_jit,
+ /*Default=*/false))
+ CmdArgs.push_back(Args.MakeArgString("-target-embed-bc"));
}
// Construct the link job so we can wrap around it.
Index: clang/include/clang/Driver/Options.td
===================================================================
--- clang/include/clang/Driver/Options.td
+++ clang/include/clang/Driver/Options.td
@@ -2460,6 +2460,10 @@
Group<f_Group>, Flags<[CC1Option, NoArgumentUnused, HelpHidden]>;
def fno_openmp_assume_threads_oversubscription : Flag<["-"], "fno-openmp-assume-threads-oversubscription">,
Group<f_Group>, Flags<[CC1Option, NoArgumentUnused, HelpHidden]>;
+def fopenmp_target_jit : Flag<["-"], "fopenmp-target-jit">, Group<f_Group>,
+ HelpText<"Enable JIT comilation for OpenMP Offloading">, Flags<[ NoArgumentUnused]>;
+def fno_openmp_target_jit : Flag<["-"], "fno-openmp-target-jit">, Group<f_Group>,
+ Flags<[NoArgumentUnused, HelpHidden]>;
defm openmp_target_new_runtime: BoolFOption<"openmp-target-new-runtime",
LangOpts<"OpenMPTargetNewRuntime">, DefaultTrue,
PosFlag<SetTrue, [CC1Option], "Use the new bitcode library for OpenMP offloading">,
Index: clang/include/clang/Basic/DiagnosticDriverKinds.td
===================================================================
--- clang/include/clang/Basic/DiagnosticDriverKinds.td
+++ clang/include/clang/Basic/DiagnosticDriverKinds.td
@@ -161,6 +161,8 @@
"invalid Xarch argument: '%0', options requiring arguments are unsupported">;
def err_drv_Xopenmp_target_missing_triple : Error<
"cannot deduce implicit triple value for -Xopenmp-target, specify triple using -Xopenmp-target=<triple>">;
+def err_drv_openmp_jit_without_lto : Error<
+ "cannot enable OpenMP offloading JIT, specify bitcode compilation with '-foffload-lto'">;
def err_drv_invalid_Xopenmp_target_with_args : Error<
"invalid -Xopenmp-target argument: '%0', options requiring arguments are unsupported">;
def err_drv_argument_only_allowed_with : Error<
_______________________________________________
cfe-commits mailing list
cfe-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
