[clang] 97c62b8 - [LinkerWrapper] Forward `-mllvm` and `--offload-opt` arguments to device (#100424)

[via cfe-commits]

Author: Joseph Huber
Date: 2024-07-29T09:12:14-05:00
New Revision: 97c62b8f7501d1c6c2f507b075fbe45a31d2b9dc

URL: https://github.com/llvm/llvm-project/commit/97c62b8f7501d1c6c2f507b075fbe45a31d2b9dc
DIFF: https://github.com/llvm/llvm-project/commit/97c62b8f7501d1c6c2f507b075fbe45a31d2b9dc.diff

LOG: [LinkerWrapper] Forward `-mllvm` and `--offload-opt` arguments to device (#100424)

Summary:
Previously we could parse these internally as they would be used by the
embedded LTO job. Now, this LTO is passed to the linker utilities which
means these need to be forwarded. So this can now either be done with
`--offload-opt` which works in the clang job, or with `-Xoffload-linker`
manually.

Fixes https://github.com/llvm/llvm-project/issues/100212

Added: 
    

Modified: 
    clang/test/Driver/linker-wrapper.c
    clang/tools/clang-linker-wrapper/ClangLinkerWrapper.cpp
    clang/tools/clang-linker-wrapper/LinkerWrapperOpts.td

Removed: 
    


################################################################################
diff  --git a/clang/test/Driver/linker-wrapper.c b/clang/test/Driver/linker-wrapper.c
index 342907c1a3390..f165a410c1929 100644
--- a/clang/test/Driver/linker-wrapper.c
+++ b/clang/test/Driver/linker-wrapper.c
@@ -234,3 +234,13 @@ __attribute__((visibility("protected"), used)) int x;
 // RUN: | FileCheck %s --check-prefix=OVERRIDE
 // OVERRIDE-NOT: clang
 // OVERRIDE: /usr/bin/ld
+
+// RUN: clang-offload-packager -o %t.out \
+// RUN:   --image=file=%t.elf.o,kind=openmp,triple=amdgcn-amd-amdhsa,arch=gfx908
+// RUN: %clang -cc1 %s -triple x86_64-unknown-linux-gnu -emit-obj -o %t.o -fembed-offload-object=%t.out
+// RUN: clang-linker-wrapper --host-triple=x86_64-unknown-linux-gnu --dry-run --offload-opt=-pass-remarks=foo \
+// RUN:   --linker-path=/usr/bin/ld %t.o -o a.out 2>&1 | FileCheck %s --check-prefix=OFFLOAD-OPT
+// RUN: clang-linker-wrapper --host-triple=x86_64-unknown-linux-gnu --dry-run -mllvm -pass-remarks=foo \
+// RUN:   --linker-path=/usr/bin/ld %t.o -o a.out 2>&1 | FileCheck %s --check-prefix=OFFLOAD-OPT
+
+// OFFLOAD-OPT: clang{{.*}}-Wl,--plugin-opt=-pass-remarks=foo

diff  --git a/clang/tools/clang-linker-wrapper/ClangLinkerWrapper.cpp b/clang/tools/clang-linker-wrapper/ClangLinkerWrapper.cpp
index 4bb021eae25a8..2db7b6ac823ec 100644
--- a/clang/tools/clang-linker-wrapper/ClangLinkerWrapper.cpp
+++ b/clang/tools/clang-linker-wrapper/ClangLinkerWrapper.cpp
@@ -297,7 +297,8 @@ Expected<std::string> findProgram(StringRef Name, ArrayRef<StringRef> Paths) {
 /// supported by the toolchain.
 bool linkerSupportsLTO(const ArgList &Args) {
   llvm::Triple Triple(Args.getLastArgValue(OPT_triple_EQ));
-  return Triple.isNVPTX() || Triple.isAMDGPU();
+  return Triple.isNVPTX() || Triple.isAMDGPU() ||
+         Args.getLastArgValue(OPT_linker_path_EQ).ends_with("ld.lld");
 }
 
 /// Returns the hashed value for a constant string.
@@ -524,6 +525,13 @@ Expected<StringRef> clang(ArrayRef<StringRef> InputFiles, const ArgList &Args) {
       Args.MakeArgString("-" + OptLevel),
   };
 
+  // Forward all of the `--offload-opt` and similar options to the device.
+  if (linkerSupportsLTO(Args)) {
+    for (auto &Arg : Args.filtered(OPT_offload_opt_eq_minus, OPT_mllvm))
+      CmdArgs.push_back(
+          Args.MakeArgString("-Wl,--plugin-opt=" + StringRef(Arg->getValue())));
+  }
+
   if (!Triple.isNVPTX())
     CmdArgs.push_back("-Wl,--no-undefined");
 
@@ -1756,7 +1764,7 @@ int main(int Argc, char **Argv) {
   for (const opt::Arg *Arg : Args.filtered(OPT_mllvm))
     NewArgv.push_back(Arg->getValue());
   for (const opt::Arg *Arg : Args.filtered(OPT_offload_opt_eq_minus))
-    NewArgv.push_back(Args.MakeArgString(StringRef("-") + Arg->getValue()));
+    NewArgv.push_back(Arg->getValue());
   SmallVector<PassPlugin, 1> PluginList;
   PassPlugins.setCallback([&](const std::string &PluginPath) {
     auto Plugin = PassPlugin::Load(PluginPath);

diff  --git a/clang/tools/clang-linker-wrapper/LinkerWrapperOpts.td b/clang/tools/clang-linker-wrapper/LinkerWrapperOpts.td
index 9c27e588fc4f5..a87d5ec8aa9b3 100644
--- a/clang/tools/clang-linker-wrapper/LinkerWrapperOpts.td
+++ b/clang/tools/clang-linker-wrapper/LinkerWrapperOpts.td
@@ -98,7 +98,7 @@ def mllvm : Separate<["-"], "mllvm">, Flags<[WrapperOnlyOption]>,
   HelpText<"Arguments passed to LLVM, including Clang invocations, for which "
            "the '-mllvm' prefix is preserved. Use '-mllvm --help' for a list "
            "of options.">;
-def offload_opt_eq_minus : Joined<["--", "-"], "offload-opt=-">, Flags<[HelpHidden, WrapperOnlyOption]>,
+def offload_opt_eq_minus : Joined<["--", "-"], "offload-opt=">, Flags<[HelpHidden, WrapperOnlyOption]>,
   HelpText<"Options passed to LLVM, not including the Clang invocation. Use "
            "'--offload-opt=--help' for a list of options.">;