<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html><head><meta content="text/html;charset=UTF-8" http-equiv="Content-Type"></head><body ><div style="font-family: Verdana, Arial, Helvetica, sans-serif; font-size: 10pt;"><div>Hello, everyone!<br></div><div><br></div><div>I'm a newcomer, and want to make some contributions to the LLVM community. Is here the right place to reach out for help? Please forgive me if I did things wrong, as I'm unfamiliar with the LLVM workflow :-) <br></div><div><br></div><div>So a few days ago I noticed an issue in the bugzilla: <a target="_blank" href="https://bugs.llvm.org/show_bug.cgi?id=52444">https://bugs.llvm.org/show_bug.cgi?id=52444</a>, I thought it would be suitable for me to work on. But now I run into some problems:<br></div><div><br></div><div>* What is meaning of the capitalized words in tests comments?<br></div><div>For example, in `llvm-project/clang/test/CodeGen/builtins-elementwise-math.c`:<br></div><div>```<br></div><div>// RUN: %clang_cc1 -triple x86_64-apple-darwin %s -emit-llvm -disable-llvm-passes -o - | FileCheck %s<br></div><div>// CHECK-LABEL: define void @test_builtin_elementwise_abs(
<br></div><div>// CHECK: [[F1:%.+]] = load float, float* %f1.addr, align 4
<br></div><div>// CHECK-NEXT: call float @llvm.fabs.f32(float [[F1]])<br></div><div>```<br></div><div>What do `RUN`, `CHECK` mean? I can guess they are some test instructions, so I briefly look through the docs, but I can't find anything useful :-( I'm sorry but the docs are so much, it's hard to find something I actually don't know what is.<br></div><div><br></div><div>* How can I write my own test for codegen?<br></div><div>The actual code part is not that hard, problems came in when I want to write some tests. The fact is that I'm unfamiliar with LLVM IR, so I don't know how to write the expected output...<br></div><div><br></div><div>Thanks so much for people who offer me help!<br></div><div><br></div><div>Best regards,<br></div><div>Jun Zhang<br></div></div><br></body></html>