From 6ae1c0327af64d12e5b0d675c3c7e61343ef0319 Mon Sep 17 00:00:00 2001 From: Jakob Degen Date: Tue, 9 Aug 2022 01:44:32 -0700 Subject: [PATCH] Mention `unit-test` in MIR opt test README --- src/test/mir-opt/README.md | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/src/test/mir-opt/README.md b/src/test/mir-opt/README.md index a0550466cf07b..0721d9f7019bc 100644 --- a/src/test/mir-opt/README.md +++ b/src/test/mir-opt/README.md @@ -14,6 +14,18 @@ presence of pointers in constants or other bit width dependent things. In that c to your test, causing separate files to be generated for 32bit and 64bit systems. +## Unit testing + +If you are only testing the behavior of a particular mir-opt pass on some specific input (as is +usually the case), you should add + +``` +// unit-test: PassName +``` + +to the top of the file. This makes sure that other passes don't run which means you'll get the input +you expected and your test won't break when other code changes. + ## Emit a diff of the mir for a specific optimization This is what you want most often when you want to see how an optimization changes the MIR.