[clang] c45d2df - [Clang] Add options in LTO mode when cross compiling for AMDGPU

[Joseph Huber via cfe-commits]

Author: Joseph Huber
Date: 2023-02-22T10:14:05-06:00
New Revision: c45d2df05e0e7b6f2517aa2933a24928b4942a3f

URL: https://github.com/llvm/llvm-project/commit/c45d2df05e0e7b6f2517aa2933a24928b4942a3f
DIFF: https://github.com/llvm/llvm-project/commit/c45d2df05e0e7b6f2517aa2933a24928b4942a3f.diff

LOG: [Clang] Add options in LTO mode when cross compiling for AMDGPU

The AMDGPU toolchain support directly compiling GPU images using
cross-compilation such as `clang --target=amdgcn-amd-amdhsa foo.c`.
However, when attempting to link bitcode this does not work because the
`-mcpu` options are not forwarded to the linker among others. This patch
simply adds them so that `clang --target=amdgcn-amd-amdhsa foo.c -flto`
works correctly.

Reviewed By: JonChesterfield

Differential Revision: https://reviews.llvm.org/D144505

Added: 
    

Modified: 
    clang/lib/Driver/ToolChains/AMDGPU.cpp
    clang/test/Driver/amdgpu-toolchain.c

Removed: 
    


################################################################################
diff  --git a/clang/lib/Driver/ToolChains/AMDGPU.cpp b/clang/lib/Driver/ToolChains/AMDGPU.cpp
index f30c1075eb7a3..08496c1abbc41 100644
--- a/clang/lib/Driver/ToolChains/AMDGPU.cpp
+++ b/clang/lib/Driver/ToolChains/AMDGPU.cpp
@@ -540,6 +540,9 @@ void amdgpu::Linker::ConstructJob(Compilation &C, const JobAction &JA,
   ArgStringList CmdArgs;
   addLinkerCompressDebugSectionsOption(getToolChain(), Args, CmdArgs);
   AddLinkerInputs(getToolChain(), Inputs, Args, CmdArgs, JA);
+  if (C.getDriver().isUsingLTO())
+    addLTOOptions(getToolChain(), Args, CmdArgs, Output, Inputs[0],
+                  C.getDriver().getLTOMode() == LTOK_Thin);
   CmdArgs.push_back("-shared");
   CmdArgs.push_back("-o");
   CmdArgs.push_back(Output.getFilename());

diff  --git a/clang/test/Driver/amdgpu-toolchain.c b/clang/test/Driver/amdgpu-toolchain.c
index c0a435428de60..a00c75b83f3e0 100644
--- a/clang/test/Driver/amdgpu-toolchain.c
+++ b/clang/test/Driver/amdgpu-toolchain.c
@@ -13,4 +13,4 @@
 // RUN: %clang -### --target=amdgcn-amd-amdhsa -mcpu=gfx906 -nogpulib \
 // RUN:   -flto %s 2>&1 | FileCheck -check-prefix=LTO %s
 // LTO: clang{{.*}} "-flto=full"
-// LTO: ld.lld{{.*}}
+// LTO: ld.lld{{.*}}-plugin-opt=mcpu=gfx906