How to write tests for v8?

[Zhao Jiazhong]

Hi!

I'm working on a CL: https://chromium-review.googlesource.com/c/v8/v8/+/2095645, which fixes a bug on mips platform, and now I need to add a test for the bug, but I'm not familiar with it. 

The bug is: on mips, TurboAssembler::Call may emit a trampoline after the jump instruction, which leading to a wrong record in SafepointTable.

I think I need a test to invoke the TurboAssembler::Call, and then invoke SafepointeTable::FindEntry, if the bug occurs, FindEntry would fail. But I have no idea how to implement it. Anyone have some tips or some related documents to learn?

Thanks in advance!

[Georg Neis]

I can see two approaches of writing a test for the bug: 1) generate
code such that its safepoint table is faulty and then manually inspect
its safepoint table, or 2) generate code such that its safepoint table
is faulty and running it will trigger a GC or deopt at the problematic
pc, and run this code. (1) will probably require you to expose some
internals for testing. We can discuss details in the code review tool.

Best,
Georg