Fix -gz=zlib options for linker

[yaxunl]

Summary

gcc translates -gz=zlib to --compress-debug-options=zlib for both assembler and linker
but clang only does this for assembler.

The linker needs --compress-debug-options=zlib option to compress the debug sections
in the generated executable or shared library.

Due to this bug, -gz=zlib has no effect on the generated executable or shared library.

This patch fixes that.

[MaskRay]

clang/test/Driver/gz.c

1

This can be merged into compress.c
You may delete some -c from compress.c to exercise the linker stage.

clang/test/Driver/hip-gz-options.hip

1

REQUIRES values can be comma separated

5

Is -target (or --target=) needed?

15

Delete trailing empty lines

[MaskRay]

clang/test/Driver/hip-gz-options.hip

6

-ggdb is unrelated

6

Sorry it is related.

[yaxunl]

revised by Fangrui's comments.

[yaxunl]

clang/test/Driver/gz.c

1

done

clang/test/Driver/hip-gz-options.hip

1

merged

5

yes. added

15

done

[MaskRay]

clang/test/Driver/compress.c

21 ↗

(On Diff #291227)

You can delete -fintegrated-as since it is the default for most targets/OSes.

26 ↗

(On Diff #291227)

If the user sets CLANG_DEFAULT_LINKER to a string not containing "ld", this line will not match. Matching a different substring on the linker command line can be more robust, e.g. "-m" "elf_x86_64"

30 ↗

(On Diff #291227)

Delete -fintegrated-as if it is the default on amdgcn-amd-amdhsa

[yaxunl]

fix tests

clang/test/Driver/compress.c

26 ↗

(On Diff #291227)

"-m" "elf_x86_64" only works for x86_64, but we also have amdgcn target.

I will just remove "ld".

[MaskRay]

clang/test/Driver/hip-gz-options.hip

2

clang-driver is for some legacy cygwin stuff. It should not be needed.

Does --offload-arch=gfx906 have special requirement that the backend is needed? For most other driver tests x86-registered-target is not needed to test %clang -target x86_64

13

Do the two patterns require CHECK-DAG?

15

This ".*ld.*" needs to be removed as well

[yaxunl]

fix tests

clang/test/Driver/hip-gz-options.hip

2

This may be unnecessary. I will remove it.

On the other hand, I think it requires zlib, so I will add zlib.

Also I separated the test for target amdgcn from compress.c since it requires amdgpu-registered-target.

13

only the middle two steps need CHECK-DAG

[MaskRay]

clang/test/Driver/hip-gz-options.hip

2

LG. clang-driver can still be removed

15

Since this is no longer a regex you can remove the surround {{ }}

[yaxunl]

clang/test/Driver/hip-gz-options.hip

2

will do when committing

15

will do when committing

[nemanjai]

This broke the PPC LLD bot and the failure has been ignored for 4 days. I believe it should be fixed with 3bc3983f229.

[yaxunl]

In D87321#2274731, @nemanjai wrote:

This broke the PPC LLD bot and the failure has been ignored for 4 days. I believe it should be fixed with 3bc3983f229.

Sorry I thought I have fixed that but forgot to check. Not sure if this will cause regression on cygwin or msvc. If so pls let me know. Thanks.

[emaste]

I just ran into this issue on FreeBSD, bug report in https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=253942

clang/lib/Driver/ToolChains/FreeBSD.cpp needs updating for this change also

clang/lib/Driver/ToolChains/AMDGPU.cpp

 void amdgpu::Linker::ConstructJob(Compilation &C, const JobAction &JA,
                                   const InputInfo &Output,
                                   const InputInfoList &Inputs,
                                   const ArgList &Args,
                                   const char *LinkingOutput) const {
 
   std::string Linker = getToolChain().GetProgramPath(getShortName());
   ArgStringList CmdArgs;
+  addLinkerCompressDebugSectionsOption(getToolChain(), Args, CmdArgs);
   AddLinkerInputs(getToolChain(), Inputs, Args, CmdArgs, JA);
   CmdArgs.push_back("-shared");
   CmdArgs.push_back("-o");
   CmdArgs.push_back(Output.getFilename());
   C.addCommand(
       std::make_unique<Command>(JA, *this, ResponseFileSupport::AtFileCurCP(),
                                 Args.MakeArgString(Linker), CmdArgs, Inputs));
 }

clang/lib/Driver/ToolChains/CommonArgs.h

 
 void addPathIfExists(const Driver &D, const Twine &Path,
                      ToolChain::path_list &Paths);
 
 void AddLinkerInputs(const ToolChain &TC, const InputInfoList &Inputs,
                      const llvm::opt::ArgList &Args,
                      llvm::opt::ArgStringList &CmdArgs, const JobAction &JA);
 
+void addLinkerCompressDebugSectionsOption(const ToolChain &TC,
+                                          const llvm::opt::ArgList &Args,
+                                          llvm::opt::ArgStringList &CmdArgs);
+
 void claimNoWarnArgs(const llvm::opt::ArgList &Args);
 
 bool addSanitizerRuntimes(const ToolChain &TC, const llvm::opt::ArgList &Args,
                           llvm::opt::ArgStringList &CmdArgs);
 
 void linkSanitizerRuntimeDeps(const ToolChain &TC,
                               llvm::opt::ArgStringList &CmdArgs);
 

clang/lib/Driver/ToolChains/CommonArgs.cpp

else if (A.getOption().matches(options::OPT_z)) {
       A.claim();
       A.render(Args, CmdArgs);
     } else {
       A.renderAsInput(Args, CmdArgs);
     }
   }
 }
 
+void tools::addLinkerCompressDebugSectionsOption(
+    const ToolChain &TC, const llvm::opt::ArgList &Args,
+    llvm::opt::ArgStringList &CmdArgs) {
+  // GNU ld supports --compress-debug-sections=none|zlib|zlib-gnu|zlib-gabi
+  // whereas zlib is an alias to zlib-gabi. Therefore -gz=none|zlib|zlib-gnu
+  // are translated to --compress-debug-sections=none|zlib|zlib-gnu.
+  // -gz is not translated since ld --compress-debug-sections option requires an
+  // argument.
+  if (const Arg *A = Args.getLastArg(options::OPT_gz_EQ)) {
+    StringRef V = A->getValue();
+    if (V == "none" || V == "zlib" || V == "zlib-gnu")
+      CmdArgs.push_back(Args.MakeArgString("--compress-debug-sections=" + V));
+    else
+      TC.getDriver().Diag(diag::err_drv_unsupported_option_argument)
+          << A->getOption().getName() << V;
+  }
+}
+
 void tools::AddTargetFeature(const ArgList &Args,
                              std::vector<StringRef> &Features,
                              OptSpecifier OnOpt, OptSpecifier OffOpt,
                              StringRef FeatureName) {
   if (Arg *A = Args.getLastArg(OnOpt, OffOpt)) {
     if (A->getOption().matches(OnOpt))
       Features.push_back(Args.MakeArgString("+" + FeatureName));
     else

clang/lib/Driver/ToolChains/Gnu.cpp

addLTOOptions(ToolChain, Args, CmdArgs, Output, Inputs[0],
                   D.getLTOMode() == LTOK_Thin);
   }
 
   if (Args.hasArg(options::OPT_Z_Xlinker__no_demangle))
     CmdArgs.push_back("--no-demangle");
 
   bool NeedsSanitizerDeps = addSanitizerRuntimes(ToolChain, Args, CmdArgs);
   bool NeedsXRayDeps = addXRayRuntime(ToolChain, Args, CmdArgs);
+  addLinkerCompressDebugSectionsOption(ToolChain, Args, CmdArgs);
   AddLinkerInputs(ToolChain, Inputs, Args, CmdArgs, JA);
   // The profile runtime also needs access to system libraries.
   getToolChain().addProfileRTLibs(Args, CmdArgs);
 
   if (D.CCCIsCXX() &&
       !Args.hasArg(options::OPT_nostdlib, options::OPT_nodefaultlibs)) {
     if (ToolChain.ShouldLinkCXXStdlib(Args)) {
       bool OnlyLibstdcxxStatic = Args.hasArg(options::OPT_static_libstdcxx) &&

clang/lib/Driver/ToolChains/HIP.cpp

void AMDGCN::Linker::constructLldCommand(Compilation &C, const JobAction &JA,
   for (const Arg *A : Args.filtered(options::OPT_mllvm)) {
     LldArgs.push_back(
         Args.MakeArgString(Twine("-plugin-opt=") + A->getValue(0)));
   }
 
   if (C.getDriver().isSaveTempsEnabled())
     LldArgs.push_back("-save-temps");
 
+  addLinkerCompressDebugSectionsOption(TC, Args, LldArgs);
+
   LldArgs.append({"-o", Output.getFilename()});
   for (auto Input : Inputs)
     LldArgs.push_back(Input.getFilename());
   const char *Lld = Args.MakeArgString(getToolChain().GetProgramPath("lld"));
   C.addCommand(std::make_unique<Command>(JA, *this, ResponseFileSupport::None(),
                                          Lld, LldArgs, Inputs));
 }
 

clang/test/Driver/gz.c

+// RUN: %clang -### -target x86_64-unknown-linux-gnu -g -gz=none %s 2>&1 | \
+// RUN:    FileCheck -check-prefix=NONE %s
+// RUN: %clang -### -target amdgcn-amd-amdhsa -nogpulib -g -gz=none %s 2>&1 | \
+// RUN:    FileCheck -check-prefix=NONE %s
+
+// NONE: {{".*clang.*".* "--compress-debug-sections=none"}}
+// NONE: {{".*ld.*".* "--compress-debug-sections=none"}}
+
+// RUN: %clang -### -target x86_64-unknown-linux-gnu -g -gz=zlib %s 2>&1 | \
+// RUN:    FileCheck -check-prefix=ZLIB %s
+// RUN: %clang -### -target amdgcn-amd-amdhsa -nogpulib -g -gz=zlib %s 2>&1 | \
+// RUN:    FileCheck -check-prefix=ZLIB %s
+
+// ZLIB: {{".*clang.*".* "--compress-debug-sections=zlib"}}
+// ZLIB: {{".*ld.*".* "--compress-debug-sections=zlib"}}
+
+// RUN: %clang -### -target x86_64-unknown-linux-gnu -g -gz=zlib-gnu %s 2>&1 | \
+// RUN:    FileCheck -check-prefix=ZLIB-GNU %s
+// RUN: %clang -### -target amdgcn-amd-amdhsa -nogpulib -g -gz=zlib-gnu %s 2>&1 | \
+// RUN:    FileCheck -check-prefix=ZLIB-GNU %s
+
+// ZLIB-GNU: {{".*clang.*".* "--compress-debug-sections=zlib-gnu"}}
+// ZLIB-GNU: {{".*ld.*".* "--compress-debug-sections=zlib-gnu"}}

clang/test/Driver/hip-gz-options.hip

+// REQUIRES: clang-driver
+// REQUIRES: x86-registered-target
+// REQUIRES: amdgpu-registered-target
+
+// RUN: %clang -### --offload-arch=gfx906 %s -nogpulib -nogpuinc \
+// RUN:   -ggdb -gz=zlib 2>&1 | FileCheck %s
+
+// RUN: %clang -### -fgpu-rdc --offload-arch=gfx906 %s -nogpulib -nogpuinc \
+// RUN:   -ggdb -gz=zlib 2>&1 | FileCheck %s
+
+// CHECK: {{".*clang.*" .* "--compress-debug-sections=zlib"}}
+// CHECK-DAG: {{".*lld.*" .* "--compress-debug-sections=zlib"}}
+// CHECK-DAG: {{".*clang.*" .* "--compress-debug-sections=zlib"}}
+// CHECK: {{".*ld.*" .* "--compress-debug-sections=zlib"}}
+