From 3addd89dd0ca6f609da36be6e70a5053bdb5f48e Mon Sep 17 00:00:00 2001 From: Tobias Grosser Date: Sat, 17 Jun 2017 07:45:44 +0000 Subject: [PATCH] Add information about bisecting llvm-svn: 305633 --- polly/docs/TipsAndTricks.rst | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/polly/docs/TipsAndTricks.rst b/polly/docs/TipsAndTricks.rst index 30efd02b8d0e..71758891c73a 100644 --- a/polly/docs/TipsAndTricks.rst +++ b/polly/docs/TipsAndTricks.rst @@ -37,3 +37,16 @@ Understanding which pass makes a particular change - ``$ opt -O3 -polly -debug-pass=Arguments`` to get all passes that are run by default. ``-debug-pass=Arguments`` will list all passes that have run. - Bisect down to the pass that changes it. + +Debugging regressions introduced at some unknown earlier point +-------------------------------------------------------------- + +In case of a regression in performance or correctness (e.g., an earlier version +of Polly behaved as expected and a later version does not), bisecting over the +version history is the standard approach to identify the commit that introduced +the regression. + +LLVM has a single repository that contains all projects. It can be cloned at: +``_. How to bisect on a +git repository is explained here +`