[clang] a47b1cf - [OpenMP] Embed bitcode after optimizations instead of linking

[Joseph Huber via cfe-commits]

Author: Joseph Huber
Date: 2022-01-31T23:11:42-05:00
New Revision: a47b1cf306fb7494d493784c25dafb2dd6084b99

URL: https://github.com/llvm/llvm-project/commit/a47b1cf306fb7494d493784c25dafb2dd6084b99
DIFF: https://github.com/llvm/llvm-project/commit/a47b1cf306fb7494d493784c25dafb2dd6084b99.diff

LOG: [OpenMP] Embed bitcode after optimizations instead of linking

Summary:
Various changes to the linker wrapper, and the bitcode embedding is not
done after the optimizations have run rather than after linking is done.
This saves time when doing JIT.

Added: 
    

Modified: 
    clang/tools/clang-linker-wrapper/ClangLinkerWrapper.cpp

Removed: 
    


################################################################################
diff  --git a/clang/tools/clang-linker-wrapper/ClangLinkerWrapper.cpp b/clang/tools/clang-linker-wrapper/ClangLinkerWrapper.cpp
index 9f1f4acdf3bae..8331bda62420b 100644
--- a/clang/tools/clang-linker-wrapper/ClangLinkerWrapper.cpp
+++ b/clang/tools/clang-linker-wrapper/ClangLinkerWrapper.cpp
@@ -83,7 +83,7 @@ static cl::opt<std::string>
                    cl::desc("Path for the target bitcode library"),
                    cl::cat(ClangLinkerWrapperCategory));
 
-static cl::opt<bool> EmbedBC(
+static cl::opt<bool> EmbedBitcode(
     "target-embed-bc", cl::ZeroOrMore,
     cl::desc("Embed linked bitcode instead of an executable device image"),
     cl::init(false), cl::cat(ClangLinkerWrapperCategory));
@@ -657,7 +657,7 @@ void diagnosticHandler(const DiagnosticInfo &DI) {
     WithColor::note(errs(), LinkerExecutable) << ErrStorage << "\n";
     break;
   case DS_Remark:
-    WithColor::remark(errs(), LinkerExecutable) << ErrStorage << "\n";
+    WithColor::remark(errs()) << ErrStorage << "\n";
     break;
   }
 }
@@ -710,7 +710,7 @@ std::unique_ptr<lto::LTO> createLTO(
   Conf.PTO.LoopVectorization = Conf.OptLevel > 1;
   Conf.PTO.SLPVectorization = Conf.OptLevel > 1;
 
-  Conf.PostInternalizeModuleHook = Hook;
+  Conf.PostOptModuleHook = Hook;
   if (TheTriple.isNVPTX())
     Conf.CGFileType = CGFT_AssemblyFile;
   else
@@ -781,6 +781,8 @@ Error linkBitcodeFiles(SmallVectorImpl<std::string> &InputFiles,
   if (BitcodeFiles.empty())
     return Error::success();
 
+  assert(!BitcodeLibrary.empty() && "Bitcode linking without `-foffload-lto`");
+
   auto HandleError = [&](std::error_code EC) {
     logAllUnhandledErrors(errorCodeToError(EC),
                           WithColor::error(errs(), LinkerExecutable));
@@ -805,7 +807,7 @@ Error linkBitcodeFiles(SmallVectorImpl<std::string> &InputFiles,
 
   // We assume visibility of the whole program if every input file was bitcode.
   bool WholeProgram = BitcodeFiles.size() == InputFiles.size();
-  auto LTOBackend = (EmbedBC)
+  auto LTOBackend = (EmbedBitcode)
                         ? createLTO(TheTriple, Arch, WholeProgram, LinkOnly)
                         : createLTO(TheTriple, Arch, WholeProgram);
 
@@ -879,14 +881,13 @@ Error linkBitcodeFiles(SmallVectorImpl<std::string> &InputFiles,
     return Err;
 
   // Is we are compiling for NVPTX we need to run the assembler first.
-  for (auto &File : Files) {
-    if (!TheTriple.isNVPTX() || EmbedBC)
-      continue;
-
-    auto FileOrErr = nvptx::assemble(File, TheTriple, Arch);
-    if (!FileOrErr)
-      return FileOrErr.takeError();
-    File = *FileOrErr;
+  if (TheTriple.isNVPTX() && !EmbedBitcode) {
+    for (auto &File : Files) {
+      auto FileOrErr = nvptx::assemble(File, TheTriple, Arch);
+      if (!FileOrErr)
+        return FileOrErr.takeError();
+      File = *FileOrErr;
+    }
   }
 
   // Append the new inputs to the device linker input.
@@ -918,7 +919,7 @@ Error linkDeviceFiles(ArrayRef<DeviceFile> DeviceFiles,
       return Err;
 
     // If we are embedding bitcode for JIT, skip the final device linking.
-    if (EmbedBC) {
+    if (EmbedBitcode) {
       assert(!LinkerInput.getValue().empty() && "No bitcode image to embed");
       LinkedImages.push_back(LinkerInput.getValue().front());
       continue;
@@ -1080,8 +1081,8 @@ int main(int argc, const char **argv) {
     if (Optional<std::string> Library = searchLibrary(Arg, LibraryPaths))
       Filename = *Library;
 
-    if (sys::path::extension(Filename) == ".o" ||
-        sys::path::extension(Filename) == ".a") {
+    if (sys::fs::exists(Filename) && (sys::path::extension(Filename) == ".o" ||
+                                      sys::path::extension(Filename) == ".a")) {
       ErrorOr<std::unique_ptr<MemoryBuffer>> BufferOrErr =
           MemoryBuffer::getFileOrSTDIN(Filename);
       if (std::error_code EC = BufferOrErr.getError())
@@ -1100,9 +1101,6 @@ int main(int argc, const char **argv) {
 
   // Add the device bitcode library to the device files if it was passed in.
   if (!BitcodeLibrary.empty()) {
-    // FIXME: Hacky workaround to avoid a backend crash at O0.
-    if (OptLevel[1] - '0' == 0)
-      OptLevel[1] = '1';
     auto DeviceAndPath = StringRef(BitcodeLibrary).split('=');
     auto TripleAndArch = DeviceAndPath.first.rsplit('-');
     DeviceFiles.emplace_back(TripleAndArch.first, TripleAndArch.second,