Commit Graph

2 Commits

Author SHA1 Message Date
Tim Renouf f3d8295105 DivergenceAnalysis: added debug output
Summary:
This commit does two things:

1. modified the existing DivergenceAnalysis::dump() so it dumps the
   whole function with added DIVERGENT: annotations;

2. added code to do that dump if the appropriate -debug-only option is
   on.

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D47700

Change-Id: Id97b605aab1fc6f5a11a20c58a99bbe8c565bf83
llvm-svn: 336998
2018-07-13 13:13:30 +00:00
Nicolai Haehnle 13d90f324c [DivergenceAnalysis] Treat PHI with incoming undef as constant
Summary:
If a PHI has an incoming undef, we can pretend that it is equal to one
non-undef, non-self incoming value.

This is particularly relevant in combination with the StructurizeCFG
pass, which introduces PHI nodes with undefs. Previously, this lead to
branch conditions that were uniform before StructurizeCFG to become
non-uniform afterwards, which confused the SIAnnotateControlFlow
pass.

This fixes a crash when Mesa radeonsi compiles a shader from
dEQP-GLES3.functional.shaders.switch.switch_in_for_loop_dynamic_vertex

Reviewers: arsenm, tstellarAMD, jingyue

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D19013

llvm-svn: 266347
2016-04-14 17:42:47 +00:00