[clang] 4ab4e40 - [OpenMP] Always pass the optimization level to the linker wrapper

[Joseph Huber via cfe-commits]

Author: Joseph Huber
Date: 2023-08-18T17:10:13-05:00
New Revision: 4ab4e40fa2944bfd2ed44c63027e7a838043e0fd

URL: https://github.com/llvm/llvm-project/commit/4ab4e40fa2944bfd2ed44c63027e7a838043e0fd
DIFF: https://github.com/llvm/llvm-project/commit/4ab4e40fa2944bfd2ed44c63027e7a838043e0fd.diff

LOG: [OpenMP] Always pass the optimization level to the linker wrapper

The linker wrapper runs LTO internally, so it needs to know the
optimization level the user requested, if any. Previously this was only
done in `-foffload-lto` mode as we were assuming that this would enble
LTO. However, AMDGPU always performs LTO, and it's possible to run clang
on object files to link without passing this flag. So we should just
respect it always.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D158298

Added: 
    

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

Removed: 
    


################################################################################
diff  --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
index ed42eba0945ee5..8ac68df3b6db73 100644
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -8619,24 +8619,22 @@ void LinkerWrapper::ConstructJob(Compilation &C, const JobAction &JA,
     }
   }
 
-  if (D.isUsingLTO(/* IsOffload */ true)) {
-    // Pass in the optimization level to use for LTO.
-    if (const Arg *A = Args.getLastArg(options::OPT_O_Group)) {
-      StringRef OOpt;
-      if (A->getOption().matches(options::OPT_O4) ||
-          A->getOption().matches(options::OPT_Ofast))
-        OOpt = "3";
-      else if (A->getOption().matches(options::OPT_O)) {
-        OOpt = A->getValue();
-        if (OOpt == "g")
-          OOpt = "1";
-        else if (OOpt == "s" || OOpt == "z")
-          OOpt = "2";
-      } else if (A->getOption().matches(options::OPT_O0))
-        OOpt = "0";
-      if (!OOpt.empty())
-        CmdArgs.push_back(Args.MakeArgString(Twine("--opt-level=O") + OOpt));
-    }
+  // Pass in the optimization level to use for LTO.
+  if (const Arg *A = Args.getLastArg(options::OPT_O_Group)) {
+    StringRef OOpt;
+    if (A->getOption().matches(options::OPT_O4) ||
+        A->getOption().matches(options::OPT_Ofast))
+      OOpt = "3";
+    else if (A->getOption().matches(options::OPT_O)) {
+      OOpt = A->getValue();
+      if (OOpt == "g")
+        OOpt = "1";
+      else if (OOpt == "s" || OOpt == "z")
+        OOpt = "2";
+    } else if (A->getOption().matches(options::OPT_O0))
+      OOpt = "0";
+    if (!OOpt.empty())
+      CmdArgs.push_back(Args.MakeArgString(Twine("--opt-level=O") + OOpt));
   }
 
   CmdArgs.push_back(

diff  --git a/clang/test/Driver/amdgpu-openmp-toolchain.c b/clang/test/Driver/amdgpu-openmp-toolchain.c
index acb175b8663607..06b6ed324e74ec 100644
--- a/clang/test/Driver/amdgpu-openmp-toolchain.c
+++ b/clang/test/Driver/amdgpu-openmp-toolchain.c
@@ -70,3 +70,7 @@
 // RUN: not %clang -### -target x86_64-pc-linux-gnu -fopenmp --offload-arch=gfx90a,gfx90a:xnack+ \
 // RUN:   -nogpulib %s 2>&1 | FileCheck %s --check-prefix=CHECK-TARGET-ID-ERROR
 // CHECK-TARGET-ID-ERROR: error: invalid offload arch combinations: 'gfx90a' and 'gfx90a:xnack+'
+
+// RUN: %clang -### -target x86_64-pc-linux-gnu -fopenmp --offload-arch=gfx90a \
+// RUN:   -O3 -nogpulib %s 2>&1 | FileCheck %s --check-prefix=CHECK-OPT
+// CHECK-OPT: clang-linker-wrapper{{.*}}"--opt-level=O3"