[clang] 97ba3c2 - [Clang][AMDGPU] Set LTO CG opt level based on Clang option

[Scott Linder via cfe-commits]

Author: Scott Linder
Date: 2023-02-15T17:34:35Z
New Revision: 97ba3c2bec48ca55cc842c6499b19b0b8a271951

URL: https://github.com/llvm/llvm-project/commit/97ba3c2bec48ca55cc842c6499b19b0b8a271951
DIFF: https://github.com/llvm/llvm-project/commit/97ba3c2bec48ca55cc842c6499b19b0b8a271951.diff

LOG: [Clang][AMDGPU] Set LTO CG opt level based on Clang option

For AMDGCN default to mapping --lto-O# to --lto-CGO# in a 1:1 manner
(i.e. clang -O<N> implies --lto-O<N> and --lto-CGO<N>).

Ensure there is a means to override this via -Xoffload-linker and begin
to claim these arguments to avoid incorrect warnings that they are not
used.

Reviewed By: yaxunl, MaskRay

Differential Revision: https://reviews.llvm.org/D142499

Added: 
    

Modified: 
    clang/lib/Driver/ToolChains/CommonArgs.cpp
    clang/lib/Driver/ToolChains/HIPAMD.cpp
    clang/test/Driver/hip-toolchain-opt.hip

Removed: 
    


################################################################################
diff  --git a/clang/lib/Driver/ToolChains/CommonArgs.cpp b/clang/lib/Driver/ToolChains/CommonArgs.cpp
index e6360fd8edc13..c179c4152cee4 100644
--- a/clang/lib/Driver/ToolChains/CommonArgs.cpp
+++ b/clang/lib/Driver/ToolChains/CommonArgs.cpp
@@ -567,6 +567,7 @@ void tools::addLTOOptions(const ToolChain &ToolChain, const ArgList &Args,
                           ArgStringList &CmdArgs, const InputInfo &Output,
                           const InputInfo &Input, bool IsThinLTO) {
   const bool IsOSAIX = ToolChain.getTriple().isOSAIX();
+  const bool IsAMDGCN = ToolChain.getTriple().isAMDGCN();
   const char *Linker = Args.MakeArgString(ToolChain.GetLinkerPath());
   const Driver &D = ToolChain.getDriver();
   if (llvm::sys::path::filename(Linker) != "ld.lld" &&
@@ -631,9 +632,12 @@ void tools::addLTOOptions(const ToolChain &ToolChain, const ArgList &Args,
         OOpt = "2";
     } else if (A->getOption().matches(options::OPT_O0))
       OOpt = "0";
-    if (!OOpt.empty())
+    if (!OOpt.empty()) {
       CmdArgs.push_back(
           Args.MakeArgString(Twine(PluginOptPrefix) + ExtraDash + "O" + OOpt));
+      if (IsAMDGCN)
+        CmdArgs.push_back(Args.MakeArgString(Twine("--lto-CGO") + OOpt));
+    }
   }
 
   if (Args.hasArg(options::OPT_gsplit_dwarf))

diff  --git a/clang/lib/Driver/ToolChains/HIPAMD.cpp b/clang/lib/Driver/ToolChains/HIPAMD.cpp
index ff797e5959a49..3131c8ed24639 100644
--- a/clang/lib/Driver/ToolChains/HIPAMD.cpp
+++ b/clang/lib/Driver/ToolChains/HIPAMD.cpp
@@ -152,8 +152,10 @@ void AMDGCN::Linker::constructLldCommand(Compilation &C, const JobAction &JA,
 
   addLinkerCompressDebugSectionsOption(TC, Args, LldArgs);
 
-  for (auto *Arg : Args.filtered(options::OPT_Xoffload_linker))
+  for (auto *Arg : Args.filtered(options::OPT_Xoffload_linker)) {
     LldArgs.push_back(Arg->getValue(1));
+    Arg->claim();
+  }
 
   LldArgs.append({"-o", Output.getFilename()});
   for (auto Input : Inputs)

diff  --git a/clang/test/Driver/hip-toolchain-opt.hip b/clang/test/Driver/hip-toolchain-opt.hip
index a82323d3da966..501f9654a2580 100644
--- a/clang/test/Driver/hip-toolchain-opt.hip
+++ b/clang/test/Driver/hip-toolchain-opt.hip
@@ -57,6 +57,14 @@
 // RUN:   %S/Inputs/hip_multiple_inputs/b.hip \
 // RUN: 2>&1 | FileCheck --check-prefixes=ALL,Og %s
 
+// RUN: %clang -### -O0 \
+// RUN:   -Xoffload-linker --lto-CGO2 \
+// RUN:   --target=x86_64-unknown-linux-gnu \
+// RUN:   --cuda-gpu-arch=gfx900 \
+// RUN:   -c -nogpulib \
+// RUN:   %S/Inputs/hip_multiple_inputs/b.hip \
+// RUN: 2>&1 | FileCheck --check-prefixes=ALL,O0-CGO2 %s
+
 // ALL: "-cc1" "-triple" "amdgcn-amd-amdhsa"
 // DEFAULT-NOT: "-O{{.}}"
 // O0-SAME: "-O0"
@@ -66,6 +74,8 @@
 // Os-SAME: "-Os"
 // Oz-SAME: "-Oz"
 // Og-SAME: "-Og"
+// O0-CGO2-SAME: "-O0"
+// O0-CGO2-NOT: "--lto-CGO2"
 
 // ALL-NOT: "{{.*}}opt"
 
@@ -74,12 +84,22 @@
 // ALL: "{{.*}}lld{{.*}}" {{.*}} "-plugin-opt=mcpu=gfx900"
 // DEFAULT-NOT: "-plugin-opt=O{{.*}}"
 // O0-SAME: "-plugin-opt=O0"
+// O0-SAME: "--lto-CGO0"
 // O1-SAME: "-plugin-opt=O1"
+// O1-SAME: "--lto-CGO1"
 // O2-SAME: "-plugin-opt=O2"
+// O2-SAME: "--lto-CGO2"
 // O3-SAME: "-plugin-opt=O3"
+// O3-SAME: "--lto-CGO3"
 // Os-SAME: "-plugin-opt=O2"
+// Os-SAME: "--lto-CGO2"
 // Oz-SAME: "-plugin-opt=O2"
+// Oz-SAME: "--lto-CGO2"
 // Og-SAME: "-plugin-opt=O1"
+// Og-SAME: "--lto-CGO1"
+// O0-CGO2-SAME: "-plugin-opt=O0"
+// O0-CGO2-SAME: "--lto-CGO0"
+// O0-CGO2-SAME: "--lto-CGO2"
 
 // ALL: "-cc1" "-triple" "x86_64-unknown-linux-gnu"
 // DEFAULT-NOT: "-O{{.}}"
@@ -90,3 +110,5 @@
 // Os-SAME: "-Os"
 // Oz-SAME: "-Oz"
 // Og-SAME: "-Og"
+// O0-CGO2-SAME: "-O0"
+// O0-CGO2-NOT: "--lto-CGO2"