[clang] [Clang] Add a flag to include GPU startup files (PR #112025)
Joseph Huber via cfe-commits
cfe-commits at lists.llvm.org
Fri Oct 25 16:36:47 PDT 2024
https://github.com/jhuber6 updated https://github.com/llvm/llvm-project/pull/112025
>From a02a27171801ad3f5618099b5035ef8185c2f835 Mon Sep 17 00:00:00 2001
From: Joseph Huber <huberjn at outlook.com>
Date: Fri, 11 Oct 2024 12:21:49 -0500
Subject: [PATCH 1/4] [Clang] Add a flag to include GPU startup files
Summary:
The C library for GPUs provides the ability to target regular C/C++
programs by providing the C library and a file containing kernels that
call the `main` function. This is mostly used for unit tests, this patch
provides a quick way to add them without needing to know the paths. I
currently do this explicitly, but according to the libc++ contributors
we don't want to need to specify these paths manually. See the
discussion in https://github.com/llvm/llvm-project/pull/104515.
I just default to `lib/` if the target-specific one isn't found because
the linker will handle giving a reasonable error message if it's not
found. Basically the use-case looks like this.
```console
$ clang test.c --target=amdgcn-amd-amdhsa -mcpu=native -gpustartfiles
$ amdhsa-loader a.out
PASS!
```
---
clang/include/clang/Driver/Options.td | 3 +++
clang/lib/Driver/ToolChains/AMDGPU.cpp | 9 +++++++++
clang/lib/Driver/ToolChains/Cuda.cpp | 9 +++++++++
clang/test/Driver/gpustartfiles.c | 7 +++++++
4 files changed, 28 insertions(+)
create mode 100644 clang/test/Driver/gpustartfiles.c
diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
index 379e75b197cf96..3583f46a972314 100644
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -1316,6 +1316,9 @@ defm offload_via_llvm : BoolFOption<"offload-via-llvm",
BothFlags<[], [ClangOption], " LLVM/Offload as portable offloading runtime.">>;
}
+def gpustartfiles : Flag<["-"], "gpustartfiles">, Group<Link_Group>,
+ HelpText<"Link the GPU C startup utilities automatically, used for testing.">;
+
// CUDA options
let Group = cuda_Group in {
def cuda_include_ptx_EQ : Joined<["--"], "cuda-include-ptx=">,
diff --git a/clang/lib/Driver/ToolChains/AMDGPU.cpp b/clang/lib/Driver/ToolChains/AMDGPU.cpp
index 2c85d21ebd738c..9a648be4ea3915 100644
--- a/clang/lib/Driver/ToolChains/AMDGPU.cpp
+++ b/clang/lib/Driver/ToolChains/AMDGPU.cpp
@@ -648,6 +648,15 @@ void amdgpu::Linker::ConstructJob(Compilation &C, const JobAction &JA,
Args.MakeArgString("-plugin-opt=-mattr=" + llvm::join(Features, ",")));
}
+ if (Args.hasArg(options::OPT_gpustartfiles)) {
+ auto IncludePath = getToolChain().getStdlibPath();
+ if (!IncludePath)
+ IncludePath = "/lib";
+ SmallString<128> P(*IncludePath);
+ llvm::sys::path::append(P, "crt1.o");
+ CmdArgs.append({"-lc", "-lm", Args.MakeArgString(P)});
+ }
+
CmdArgs.push_back("-o");
CmdArgs.push_back(Output.getFilename());
C.addCommand(std::make_unique<Command>(
diff --git a/clang/lib/Driver/ToolChains/Cuda.cpp b/clang/lib/Driver/ToolChains/Cuda.cpp
index b368c473756731..20ec010ade04cb 100644
--- a/clang/lib/Driver/ToolChains/Cuda.cpp
+++ b/clang/lib/Driver/ToolChains/Cuda.cpp
@@ -643,6 +643,15 @@ void NVPTX::Linker::ConstructJob(Compilation &C, const JobAction &JA,
llvm::sys::path::append(DefaultLibPath, CLANG_INSTALL_LIBDIR_BASENAME);
CmdArgs.push_back(Args.MakeArgString(Twine("-L") + DefaultLibPath));
+ if (Args.hasArg(options::OPT_gpustartfiles)) {
+ auto IncludePath = getToolChain().getStdlibPath();
+ if (!IncludePath)
+ IncludePath = "/lib";
+ SmallString<128> P(*IncludePath);
+ llvm::sys::path::append(P, "crt1.o");
+ CmdArgs.append({"-lc", "-lm", Args.MakeArgString(P)});
+ }
+
C.addCommand(std::make_unique<Command>(
JA, *this,
ResponseFileSupport{ResponseFileSupport::RF_Full, llvm::sys::WEM_UTF8,
diff --git a/clang/test/Driver/gpustartfiles.c b/clang/test/Driver/gpustartfiles.c
new file mode 100644
index 00000000000000..c1b7a6fa922df4
--- /dev/null
+++ b/clang/test/Driver/gpustartfiles.c
@@ -0,0 +1,7 @@
+// RUN: %clang -target nvptx64-nvidia-cuda -march=sm_61 -gpustartfiles \
+// RUN: -nogpulib -nogpuinc -### %s 2>&1 | FileCheck -check-prefix=NVPTX %s
+// NVPTX: clang-nvlink-wrapper{{.*}}"-lc" "-lm" "{{.*}}crt1.o"
+//
+// RUN: %clang -target amdgcn-amd-amdhsa -march=gfx90a -gpustartfiles \
+// RUN: -nogpulib -nogpuinc -### %s 2>&1 | FileCheck -check-prefix=AMDGPU %s
+// AMDGPU: ld.lld{{.*}}"-lc" "-lm" "{{.*}}crt1.o"
>From 6ccba0250b564045c71ac693c2caf196ab993b1a Mon Sep 17 00:00:00 2001
From: Joseph Huber <huberjn at outlook.com>
Date: Fri, 11 Oct 2024 12:52:49 -0500
Subject: [PATCH 2/4] Add -startfiles -stdlib positive versions for GPU
---
clang/include/clang/Driver/Options.td | 7 ++++---
clang/lib/Driver/ToolChains/AMDGPU.cpp | 6 ++++--
clang/lib/Driver/ToolChains/Cuda.cpp | 6 ++++--
clang/test/Driver/gpustartfiles.c | 4 ++--
4 files changed, 14 insertions(+), 9 deletions(-)
diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
index 3583f46a972314..a10330e992d016 100644
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -1316,9 +1316,6 @@ defm offload_via_llvm : BoolFOption<"offload-via-llvm",
BothFlags<[], [ClangOption], " LLVM/Offload as portable offloading runtime.">>;
}
-def gpustartfiles : Flag<["-"], "gpustartfiles">, Group<Link_Group>,
- HelpText<"Link the GPU C startup utilities automatically, used for testing.">;
-
// CUDA options
let Group = cuda_Group in {
def cuda_include_ptx_EQ : Joined<["--"], "cuda-include-ptx=">,
@@ -5615,6 +5612,7 @@ def noprebind : Flag<["-"], "noprebind">;
def noprofilelib : Flag<["-"], "noprofilelib">;
def noseglinkedit : Flag<["-"], "noseglinkedit">;
def nostartfiles : Flag<["-"], "nostartfiles">, Group<Link_Group>;
+def startfiles : Flag<["-"], "startfiles">, Group<Link_Group>;
def nostdinc : Flag<["-"], "nostdinc">,
Visibility<[ClangOption, CLOption, DXCOption]>, Group<IncludePath_Group>,
HelpText<"Disable both standard system #include directories and builtin #include directories">;
@@ -5627,6 +5625,9 @@ def nostdincxx : Flag<["-"], "nostdinc++">, Visibility<[ClangOption, CC1Option]>
def nostdlib : Flag<["-"], "nostdlib">,
Visibility<[ClangOption, CLOption, FlangOption, DXCOption]>,
Group<Link_Group>;
+def stdlib : Flag<["-"], "stdlib">,
+ Visibility<[ClangOption, CLOption, FlangOption, DXCOption]>,
+ Group<Link_Group>;
def nostdlibxx : Flag<["-"], "nostdlib++">;
def object : Flag<["-"], "object">;
def o : JoinedOrSeparate<["-"], "o">,
diff --git a/clang/lib/Driver/ToolChains/AMDGPU.cpp b/clang/lib/Driver/ToolChains/AMDGPU.cpp
index 9a648be4ea3915..301f4855c9f250 100644
--- a/clang/lib/Driver/ToolChains/AMDGPU.cpp
+++ b/clang/lib/Driver/ToolChains/AMDGPU.cpp
@@ -648,13 +648,15 @@ void amdgpu::Linker::ConstructJob(Compilation &C, const JobAction &JA,
Args.MakeArgString("-plugin-opt=-mattr=" + llvm::join(Features, ",")));
}
- if (Args.hasArg(options::OPT_gpustartfiles)) {
+ if (Args.hasArg(options::OPT_stdlib))
+ CmdArgs.append({"-lc", "-lm"});
+ if (Args.hasArg(options::OPT_startfiles)) {
auto IncludePath = getToolChain().getStdlibPath();
if (!IncludePath)
IncludePath = "/lib";
SmallString<128> P(*IncludePath);
llvm::sys::path::append(P, "crt1.o");
- CmdArgs.append({"-lc", "-lm", Args.MakeArgString(P)});
+ CmdArgs.push_back(Args.MakeArgString(P));
}
CmdArgs.push_back("-o");
diff --git a/clang/lib/Driver/ToolChains/Cuda.cpp b/clang/lib/Driver/ToolChains/Cuda.cpp
index 20ec010ade04cb..a5c59ad21a9b3f 100644
--- a/clang/lib/Driver/ToolChains/Cuda.cpp
+++ b/clang/lib/Driver/ToolChains/Cuda.cpp
@@ -643,13 +643,15 @@ void NVPTX::Linker::ConstructJob(Compilation &C, const JobAction &JA,
llvm::sys::path::append(DefaultLibPath, CLANG_INSTALL_LIBDIR_BASENAME);
CmdArgs.push_back(Args.MakeArgString(Twine("-L") + DefaultLibPath));
- if (Args.hasArg(options::OPT_gpustartfiles)) {
+ if (Args.hasArg(options::OPT_stdlib))
+ CmdArgs.append({"-lc", "-lm"});
+ if (Args.hasArg(options::OPT_startfiles)) {
auto IncludePath = getToolChain().getStdlibPath();
if (!IncludePath)
IncludePath = "/lib";
SmallString<128> P(*IncludePath);
llvm::sys::path::append(P, "crt1.o");
- CmdArgs.append({"-lc", "-lm", Args.MakeArgString(P)});
+ CmdArgs.push_back(Args.MakeArgString(P));
}
C.addCommand(std::make_unique<Command>(
diff --git a/clang/test/Driver/gpustartfiles.c b/clang/test/Driver/gpustartfiles.c
index c1b7a6fa922df4..35dac09f658c90 100644
--- a/clang/test/Driver/gpustartfiles.c
+++ b/clang/test/Driver/gpustartfiles.c
@@ -1,7 +1,7 @@
-// RUN: %clang -target nvptx64-nvidia-cuda -march=sm_61 -gpustartfiles \
+// RUN: %clang -target nvptx64-nvidia-cuda -march=sm_61 -stdlib -startfiles \
// RUN: -nogpulib -nogpuinc -### %s 2>&1 | FileCheck -check-prefix=NVPTX %s
// NVPTX: clang-nvlink-wrapper{{.*}}"-lc" "-lm" "{{.*}}crt1.o"
//
-// RUN: %clang -target amdgcn-amd-amdhsa -march=gfx90a -gpustartfiles \
+// RUN: %clang -target amdgcn-amd-amdhsa -march=gfx90a -stdlib -startfiles \
// RUN: -nogpulib -nogpuinc -### %s 2>&1 | FileCheck -check-prefix=AMDGPU %s
// AMDGPU: ld.lld{{.*}}"-lc" "-lm" "{{.*}}crt1.o"
>From c1ec9bcf815eab8e775af8c441885301603b8ded Mon Sep 17 00:00:00 2001
From: Joseph Huber <huberjn at outlook.com>
Date: Fri, 11 Oct 2024 12:55:01 -0500
Subject: [PATCH 3/4] move test
---
clang/test/Driver/amdgpu-toolchain.c | 4 ++++
clang/test/Driver/cuda-cross-compiling.c | 4 ++++
clang/test/Driver/gpustartfiles.c | 7 -------
3 files changed, 8 insertions(+), 7 deletions(-)
delete mode 100644 clang/test/Driver/gpustartfiles.c
diff --git a/clang/test/Driver/amdgpu-toolchain.c b/clang/test/Driver/amdgpu-toolchain.c
index b60d31bae62700..c1c5aa8e90e686 100644
--- a/clang/test/Driver/amdgpu-toolchain.c
+++ b/clang/test/Driver/amdgpu-toolchain.c
@@ -32,3 +32,7 @@
// RUN: %clang -### --target=amdgcn-amd-amdhsa -mcpu=gfx906 -nogpulib \
// RUN: -r %s 2>&1 | FileCheck -check-prefixes=RELO %s
// RELO-NOT: -shared
+
+// RUN: %clang -target amdgcn-amd-amdhsa -march=gfx90a -stdlib -startfiles \
+// RUN: -nogpulib -nogpuinc -### %s 2>&1 | FileCheck -check-prefix=STARTUP %s
+// STARTUP: ld.lld{{.*}}"-lc" "-lm" "{{.*}}crt1.o"
diff --git a/clang/test/Driver/cuda-cross-compiling.c b/clang/test/Driver/cuda-cross-compiling.c
index 5f24e7a5accb08..04c5abd305950d 100644
--- a/clang/test/Driver/cuda-cross-compiling.c
+++ b/clang/test/Driver/cuda-cross-compiling.c
@@ -105,3 +105,7 @@
// RUN: | FileCheck -check-prefix=FEATURE %s
// FEATURE: clang-nvlink-wrapper{{.*}}"--feature" "+ptx63"
+
+// RUN: %clang -target nvptx64-nvidia-cuda -march=sm_61 -stdlib -startfiles \
+// RUN: -nogpulib -nogpuinc -### %s 2>&1 | FileCheck -check-prefix=STARTUP %s
+// STARTUP: clang-nvlink-wrapper{{.*}}"-lc" "-lm" "{{.*}}crt1.o"
diff --git a/clang/test/Driver/gpustartfiles.c b/clang/test/Driver/gpustartfiles.c
deleted file mode 100644
index 35dac09f658c90..00000000000000
--- a/clang/test/Driver/gpustartfiles.c
+++ /dev/null
@@ -1,7 +0,0 @@
-// RUN: %clang -target nvptx64-nvidia-cuda -march=sm_61 -stdlib -startfiles \
-// RUN: -nogpulib -nogpuinc -### %s 2>&1 | FileCheck -check-prefix=NVPTX %s
-// NVPTX: clang-nvlink-wrapper{{.*}}"-lc" "-lm" "{{.*}}crt1.o"
-//
-// RUN: %clang -target amdgcn-amd-amdhsa -march=gfx90a -stdlib -startfiles \
-// RUN: -nogpulib -nogpuinc -### %s 2>&1 | FileCheck -check-prefix=AMDGPU %s
-// AMDGPU: ld.lld{{.*}}"-lc" "-lm" "{{.*}}crt1.o"
>From 79d1432e1dafcc4ca7a1cbd04ec2c7a93bedf7cb Mon Sep 17 00:00:00 2001
From: Joseph Huber <huberjn at outlook.com>
Date: Fri, 25 Oct 2024 18:36:37 -0500
Subject: [PATCH 4/4] Update AMDGPU.cpp
---
clang/lib/Driver/ToolChains/AMDGPU.cpp | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/clang/lib/Driver/ToolChains/AMDGPU.cpp b/clang/lib/Driver/ToolChains/AMDGPU.cpp
index 301f4855c9f250..a8061ffd9321f5 100644
--- a/clang/lib/Driver/ToolChains/AMDGPU.cpp
+++ b/clang/lib/Driver/ToolChains/AMDGPU.cpp
@@ -651,7 +651,7 @@ void amdgpu::Linker::ConstructJob(Compilation &C, const JobAction &JA,
if (Args.hasArg(options::OPT_stdlib))
CmdArgs.append({"-lc", "-lm"});
if (Args.hasArg(options::OPT_startfiles)) {
- auto IncludePath = getToolChain().getStdlibPath();
+ std::optional<std::string> IncludePath = getToolChain().getStdlibPath();
if (!IncludePath)
IncludePath = "/lib";
SmallString<128> P(*IncludePath);
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