[HIP] Fix HIP include path

The clang compiler prepends the HIP header include paths to the search
list using -internal-isystem when building for the HIP language. This
prevents warnings related to things like reserved identifiers when
including the HIP headers even when ROCm is installed in a non-system
directory, such as /opt/rocm.

However, when HIP is installed in /usr, then the prepended include
path would be /usr/include. That is a problem, because the C standard
library headers are stored in /usr/include and the C++ standard
library headers must come before the C library headers in the search
path list (because the C++ standard library headers use #include_next
to include the C standard library headers).

While the HIP wrapper headers _do_ need to be earlier in the search
than the C++ headers, those headers get their own subdirectory and
their own explicit -internal-isystem argument. This include path is for
<hip/hip_runtime_api.h> and <hip/hip_runtime.h>, which do not require a
particular search ordering with respect to the C or C++ headers. Thus,
HIP include path is added after other system include paths.

With contribution from Cordell Bloor.

Reviewed by: Artem Belevich

Differential Revision: https://reviews.llvm.org/D120132

Author: yxsamliu

clang/lib/Driver/ToolChains/AMDGPU.cpp

@@ -517,7 +517,7 @@ void RocmInstallationDetector::AddHIPIncludeArgs(const ArgList &DriverArgs,
     return;
   }
 
-  CC1Args.push_back("-internal-isystem");
+  CC1Args.push_back("-idirafter");
   CC1Args.push_back(DriverArgs.MakeArgString(getIncludePath()));
   if (UsesRuntimeWrapper)
     CC1Args.append({"-include", "__clang_hip_runtime_wrapper.h"});

clang/test/Driver/hip-include-path.hip

@@ -19,24 +19,24 @@
 // COMMON-LABEL: "{{[^"]*}}clang{{[^"]*}}" "-cc1"
 // CLANG-SAME: "-internal-isystem" "{{[^"]*}}/lib{{[^"]*}}/clang/{{[^"]*}}/include/cuda_wrappers"
 // NOCLANG-NOT: "{{[^"]*}}/lib{{[^"]*}}/clang/{{[^"]*}}/include/cuda_wrappers"
-// HIP-SAME: "-internal-isystem" "{{[^"]*}}Inputs/rocm/include"
-// NOHIP-NOT: "{{.*}}Inputs/rocm/include"
+// HIP-SAME: "-idirafter" "{{[^"]*}}Inputs/rocm/include"
 // HIP-SAME: "-include" "__clang_hip_runtime_wrapper.h"
 // NOHIP-NOT: "-include" "__clang_hip_runtime_wrapper.h"
 // skip check of standard C++ include path
 // CLANG-SAME: "-internal-isystem" "{{[^"]*}}/lib{{[^"]*}}/clang/{{[^"]*}}/include"
 // NOCLANG-NOT: "{{[^"]*}}/lib{{[^"]*}}/clang/{{[^"]*}}/include"
+// NOHIP-NOT: "{{.*}}Inputs/rocm/include"
 
 // COMMON-LABEL: "{{[^"]*}}clang{{[^"]*}}" "-cc1"
 // CLANG-SAME: "-internal-isystem" "{{[^"]*}}/lib{{[^"]*}}/clang/{{[^"]*}}/include/cuda_wrappers"
 // NOCLANG-NOT: "{{[^"]*}}/lib{{[^"]*}}/clang/{{[^"]*}}/include/cuda_wrappers"
-// HIP-SAME: "-internal-isystem" "{{[^"]*}}Inputs/rocm/include"
-// NOHIP-NOT: "{{.*}}Inputs/rocm/include"
+// HIP-SAME: "-idirafter" "{{[^"]*}}Inputs/rocm/include"
 // HIP-SAME: "-include" "__clang_hip_runtime_wrapper.h"
 // NOHIP-NOT: "-include" "__clang_hip_runtime_wrapper.h"
 // skip check of standard C++ include path
 // CLANG-SAME: "-internal-isystem" "{{[^"]*}}/lib{{[^"]*}}/clang/{{[^"]*}}/include"
 // NOCLANG-NOT: "{{[^"]*}}/lib{{[^"]*}}/clang/{{[^"]*}}/include"
+// NOHIP-NOT: "{{.*}}Inputs/rocm/include"
 
 // RUN: %clang -c -### -target x86_64-unknown-linux-gnu --cuda-gpu-arch=gfx900 \
 // RUN:   -std=c++11 --rocm-path=%S/Inputs/rocm -nogpulib %s 2>&1 \
@@ -45,7 +45,7 @@
 // ROCM35-LABEL: "{{[^"]*}}clang{{[^"]*}}" "-cc1"
 // ROCM35-NOT: "{{[^"]*}}/lib{{[^"]*}}/clang/{{[^"]*}}/include/cuda_wrappers"
 // ROCM35-SAME: "-internal-isystem" "{{[^"]*}}/lib{{[^"]*}}/clang/{{[^"]*}}"
-// ROCM35-SAME: "-internal-isystem" "{{[^"]*}}Inputs/rocm/include"
+// ROCM35-SAME: "-idirafter" "{{[^"]*}}Inputs/rocm/include"
 // ROCM35-NOT: "-include" "__clang_hip_runtime_wrapper.h"
 // skip check of standard C++ include path
 // ROCM35-SAME: "-internal-isystem" "{{[^"]*}}/lib{{[^"]*}}/clang/{{[^"]*}}/include"

clang/test/Driver/rocm-detect.hip

@@ -90,7 +90,7 @@
 // SPACK: Found HIP installation: [[DIR]]/hip-4.0.0-5f63slrursbrvfe2txrrjkynbsywsob5, version 4.0.20214-a2917cd
 // SPACK: "-triple" "amdgcn-amd-amdhsa"
 // SPACK-SAME: "-mlink-builtin-bitcode" "[[DIR]]/llvm-amdgpu-4.0.0-ieagcs7inf7runpyfvepqkurasoglq4z/amdgcn/bitcode/hip.bc"
-// SPACK-SAME: "-internal-isystem" "[[DIR]]/hip-4.0.0-5f63slrursbrvfe2txrrjkynbsywsob5/include"
+// SPACK-SAME: "-idirafter" "[[DIR]]/hip-4.0.0-5f63slrursbrvfe2txrrjkynbsywsob5/include"
 
 // SPACK-MULT: InstalledDir: [[DIR:.*]]/llvm-amdgpu-4.0.0-ieagcs7inf7runpyfvepqkurasoglq4z/bin
 // SPACK-MULT-DAG: Cannot use SPACK package hip-4.0.0 at [[DIR]] due to multiple installations for the same version
@@ -101,12 +101,12 @@
 // SPACK-SET: Found HIP installation: [[DIR]]/hip-4.0.0-abcd, version 4.0.20214-a2917cd
 // SPACK-SET: "-triple" "amdgcn-amd-amdhsa"
 // SPACK-SET-SAME: "-mlink-builtin-bitcode" "[[DIR]]/llvm-amdgpu-4.0.0-ieagcs7inf7runpyfvepqkurasoglq4z/amdgcn/bitcode/hip.bc"
-// SPACK-SET-SAME: "-internal-isystem" "[[DIR]]/hip-4.0.0-abcd/include"
+// SPACK-SET-SAME: "-idirafter" "[[DIR]]/hip-4.0.0-abcd/include"
 
 // SPACK-MISS: InstalledDir: [[DIR:.*]]/llvm-amdgpu-4.0.0-ieagcs7inf7runpyfvepqkurasoglq4z/bin
 // SPACK-MISS-DAG: SPACK package hip-4.0.0 not found at [[DIR]]
 // SPACK-MISS-NOT: Found HIP installation: [[DIR]]/hip-4.0.0-5f63slrursbrvfe2txrrjkynbsywsob5, version 4.0.20214-a2917cd
-// SPACK-MISS-NOT: "-internal-isystem" "[[DIR]]/hip-4.0.0-5f63slrursbrvfe2txrrjkynbsywsob5/include"
+// SPACK-MISS-NOT: "-idirafter" "[[DIR]]/hip-4.0.0-5f63slrursbrvfe2txrrjkynbsywsob5/include"
 
 // SPACK-MISS-SILENT-NOT: SPACK package hip-{{.*}} not found at
 // SPACK-MISS-SILENT-NOT: Found HIP installation