Author: Joseph Huber Date: 2024-11-07T04:59:58-08:00 New Revision: 4fb953ac348d888541efe515439e0d844cdd7fbf
URL: https://github.com/llvm/llvm-project/commit/4fb953ac348d888541efe515439e0d844cdd7fbf DIFF: https://github.com/llvm/llvm-project/commit/4fb953ac348d888541efe515439e0d844cdd7fbf.diff LOG: [AMDGPU] Make `__GCC_DESTRUCTIVE_SIZE` 128 on AMDGPU (#115241) Summary: The cache line size on AMDGPU varies between 64 and 128 (The lowest L2 cache also goes to 256 on some architectures.) This macro is intended to present a size that will not cause destructive interference, so we choose the larger of those values. Added: Modified: clang/lib/Basic/Targets/AMDGPU.h clang/test/Driver/amdgpu-macros.cl Removed: ################################################################################ diff --git a/clang/lib/Basic/Targets/AMDGPU.h b/clang/lib/Basic/Targets/AMDGPU.h index 6edd3474d4edae..fac46f215a3736 100644 --- a/clang/lib/Basic/Targets/AMDGPU.h +++ b/clang/lib/Basic/Targets/AMDGPU.h @@ -462,6 +462,14 @@ class LLVM_LIBRARY_VISIBILITY AMDGPUTargetInfo final : public TargetInfo { } bool hasHIPImageSupport() const override { return HasImage; } + + std::pair<unsigned, unsigned> hardwareInterferenceSizes() const override { + // This is imprecise as the value can vary between 64, 128 (even 256!) bytes + // depending on the level of cache and the target architecture. We select + // the size that corresponds to the largest L1 cache line for all + // architectures. + return std::make_pair(128, 128); + } }; } // namespace targets diff --git a/clang/test/Driver/amdgpu-macros.cl b/clang/test/Driver/amdgpu-macros.cl index dd5a4483e4d607..2fedd10bb53445 100644 --- a/clang/test/Driver/amdgpu-macros.cl +++ b/clang/test/Driver/amdgpu-macros.cl @@ -153,6 +153,8 @@ // ARCH-GCN-DAG: #define __[[FAMILY]]__ 1 // ARCH-GCN-DAG: #define __amdgcn_processor__ "[[CPU]]" // ARCH-GCN-DAG: #define __AMDGCN_WAVEFRONT_SIZE [[WAVEFRONT_SIZE]] +// ARCH-GCN-DAG: #define __GCC_DESTRUCTIVE_SIZE 128 +// ARCH-GCN-DAG: #define __GCC_CONSTRUCTIVE_SIZE 128 // UNSAFEFPATOMIC-DAG: #define __AMDGCN_UNSAFE_FP_ATOMICS__ 1 // RUN: %clang -E -dM -target amdgcn -mcpu=gfx906 -mwavefrontsize64 \ _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
