llvm-project/llvm/lib/ExecutionEngine/PerfJITEvents/CMakeLists.txt

add_llvm_component_library(LLVMPerfJITEvents
  PerfJITEventListener.cpp
  )

add_dependencies(LLVMPerfJITEvents LLVMCodeGen)
[cmake] Explicitly mark libraries defined in lib/ as "Component Libraries" Summary: Most libraries are defined in the lib/ directory but there are also a few libraries defined in tools/ e.g. libLLVM, libLTO. I'm defining "Component Libraries" as libraries defined in lib/ that may be included in libLLVM.so. Explicitly marking the libraries in lib/ as component libraries allows us to remove some fragile checks that attempt to differentiate between lib/ libraries and tools/ libraires: 1. In tools/llvm-shlib, because llvm_map_components_to_libnames(LIB_NAMES "all") returned a list of all libraries defined in the whole project, there was custom code needed to filter out libraries defined in tools/, none of which should be included in libLLVM.so. This code assumed that any library defined as static was from lib/ and everything else should be excluded. With this change, llvm_map_components_to_libnames(LIB_NAMES, "all") only returns libraries that have been added to the LLVM_COMPONENT_LIBS global cmake property, so this custom filtering logic can be removed. Doing this also fixes the build with BUILD_SHARED_LIBS=ON and LLVM_BUILD_LLVM_DYLIB=ON. 2. There was some code in llvm_add_library that assumed that libraries defined in lib/ would not have LLVM_LINK_COMPONENTS or ARG_LINK_COMPONENTS set. This is only true because libraries defined lib lib/ use LLVMBuild.txt and don't set these values. This code has been fixed now to check if the library has been explicitly marked as a component library, which should now make it easier to remove LLVMBuild at some point in the future. I have tested this patch on Windows, MacOS and Linux with release builds and the following combinations of CMake options: - "" (No options) - -DLLVM_BUILD_LLVM_DYLIB=ON - -DLLVM_LINK_LLVM_DYLIB=ON - -DBUILD_SHARED_LIBS=ON - -DBUILD_SHARED_LIBS=ON -DLLVM_BUILD_LLVM_DYLIB=ON - -DBUILD_SHARED_LIBS=ON -DLLVM_LINK_LLVM_DYLIB=ON Reviewers: beanz, smeenai, compnerd, phosek Reviewed By: beanz Subscribers: wuzish, jholewinski, arsenm, dschuff, jyknight, dylanmckay, sdardis, nemanjai, jvesely, nhaehnle, mgorny, mehdi_amini, sbc100, jgravelle-google, hiraditya, aheejin, fedor.sergeev, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, steven_wu, rogfer01, MartinMosbeck, brucehoult, the_o, dexonsmith, PkmX, jocewei, jsji, dang, Jim, lenary, s.egerton, pzheng, sameer.abuasal, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D70179 2019-11-14 13:39:58 +08:00			`add_llvm_component_library(LLVMPerfJITEvents`
Add PerfJITEventListener for perf profiling support. This new JIT event listener supports generating profiling data for the linux 'perf' profiling tool, allowing it to generate function and instruction level profiles. Currently this functionality is not enabled by default, but must be enabled with LLVM_USE_PERF=yes. Given that the listener has no dependencies, it might be sensible to enable by default once the initial issues have been shaken out. I followed existing precedent in registering the listener by default in lli. Should there be a decision to enable this by default on linux, that should probably be changed. Please note that until https://reviews.llvm.org/D47343 is resolved, using this functionality with mcjit rather than orcjit will not reliably work. Disregarding the previous comment, here's an example: $ cat /tmp/expensive_loop.c bool stupid_isprime(uint64_t num) { if (num == 2) return true; if (num < 1 \|\| num % 2 == 0) return false; for(uint64_t i = 3; i < num / 2; i+= 2) { if (num % i == 0) return false; } return true; } int main(int argc, char **argv) { int numprimes = 0; for (uint64_t num = argc; num < 100000; num++) { if (stupid_isprime(num)) numprimes++; } return numprimes; } $ clang -ggdb -S -c -emit-llvm /tmp/expensive_loop.c -o /tmp/expensive_loop.ll $ perf record -o perf.data -g -k 1 ./bin/lli -jit-kind=mcjit /tmp/expensive_loop.ll 1 $ perf inject --jit -i perf.data -o perf.jit.data $ perf report -i perf.jit.data - 92.59% lli jitted-5881-2.so [.] stupid_isprime stupid_isprime main llvm::MCJIT::runFunction llvm::ExecutionEngine::runFunctionAsMain main __libc_start_main 0x4bf6258d4c544155 + 0.85% lli ld-2.27.so [.] do_lookup_x And line-level annotations also work: │ for(uint64_t i = 3; i < num / 2; i+= 2) { │1 30: movq $0x3,-0x18(%rbp) 0.03 │1 38: mov -0x18(%rbp),%rax 0.03 │ mov -0x10(%rbp),%rcx │ shr $0x1,%rcx 3.63 │ ┌──cmp %rcx,%rax │ ├──jae 6f │ │ if (num % i == 0) 0.03 │ │ mov -0x10(%rbp),%rax │ │ xor %edx,%edx 89.00 │ │ divq -0x18(%rbp) │ │ cmp $0x0,%rdx 0.22 │ │↓ jne 5f │ │ return false; │ │ movb $0x0,-0x1(%rbp) │ │↓ jmp 73 │ │ } 3.22 │1 5f:│↓ jmp 61 │ │ for(uint64_t i = 3; i < num / 2; i+= 2) { Subscribers: mgorny, llvm-commits Differential Revision: https://reviews.llvm.org/D44892 llvm-svn: 337789 2018-07-24 08:54:06 +08:00			`PerfJITEventListener.cpp`
			`)`

			`add_dependencies(LLVMPerfJITEvents LLVMCodeGen)`