42 lines
1.6 KiB
Markdown
42 lines
1.6 KiB
Markdown
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# llvm-exegesis
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`llvm-exegesis` is a benchmarking tool that accepts or assembles a snippet and
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can measure characteristics of that snippet by executing it while keeping track
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of performance counters.
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### Currently Supported Platforms
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`llvm-exegesis` is quite platform-dependent and currently only supports a couple
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platform configurations for benchmarking. The limitations are listed below.
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Analysis mode in `llvm-exegesis` is supported on all platforms on which LLVM is.
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#### Currently Supported Operating Systems for Benchmarking
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Currently, `llvm-exegesis` only supports benchmarking on Linux. This is mainly
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due to a dependency on the Linux perf subsystem for reading performance
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counters.
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The subprocess execution mode and memory annotations currently only supports
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Linux due to a heavy reliance on many Linux specific syscalls/syscall
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implementations.
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#### Currently Supported Architectures for Benchmarking
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Currently, using `llvm-exegesis` for benchmarking is supported on the following
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architectures:
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* x86
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* 64-bit only due to this being the only implemented calling convention
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in `llvm-exegesis` currently.
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* ARM
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* AArch64 only
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* MIPS
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* PowerPC (PowerPC64LE only)
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Note that not benchmarking functionality is guaranteed to work on all platforms.
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Memory annotations are currently only supported on 64-bit X86. There is no
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inherent limitations for porting memory annotations to other architectures, but
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parts of the test harness are implemented as MCJITed assembly that is generated
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in `./lib/X86/Target.cpp` that would need to be implemented on other architectures
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to bring up support.
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