llvm-project.git/llvm/test/CodeGen/SPIRV/structurizer/loop-continue-split.ll, branch users/nico/python-2 Unnamed repository; edit this file 'description' to name the repository. [SPIR-V] Fix block sorting with irreducible CFG (#116996) 2024-11-28T12:42:57+00:00 Nathan Gauër brioche@google.com 2024-11-28T12:42:57+00:00 53326ee0cf45fce3f80e2e98638dd27edb20c516 Block sorting was assuming reducible CFG. Meaning we always had a best node to continue with. Irreducible CFG makes breaks this assumption, so the algorithm looped indefinitely because no node was a valid candidate. Fixes #116692 --------- Signed-off-by: Nathan Gauër <brioche@google.com> 
Block sorting was assuming reducible CFG. Meaning we always had a best
node to continue with. Irreducible CFG makes breaks this assumption, so
the algorithm looped indefinitely because no node was a valid candidate.

Fixes #116692

---------

Signed-off-by: Nathan Gauër <brioche@google.com>
 [SPIR-V] Fix BB ordering & register lifetime (#111026) 2024-10-30T13:57:32+00:00 Nathan Gauër brioche@google.com 2024-10-30T13:57:32+00:00 cba70550ccf55c6ad3daa621bb8caf3c4ca6cbd7 The "topological" sorting was behaving incorrectly in some cases: the exit of a loop could have a lower rank than a node in the loop. This causes issues when structurizing some patterns, and also codegen issues as we could generate BBs in the incorrect order in regard to the SPIR-V spec. Fixing this ordering alone broke other parts of the structurizer, which by luck worked. Had to fix those. Added more test cases, especially to test basic patterns. I also needed to tweak/disable some tests for 2 reasons: - SPIR-V now required reg2mem/mem2reg to run. Meaning dead stores are optimized away. Some tests require tweaks to avoid having the whole function removed. - Mem2Reg will generate variable & load/stores. This generates G_BITCAST in several cases. And there is currently something wrong we do with G_BITCAST which causes MIR verifier to complain. Until this is resolved, I disabled -verify-machineinstrs flag on those tests. --------- Signed-off-by: Nathan Gauër <brioche@google.com> 
The "topological" sorting was behaving incorrectly in some cases: 
the exit of a loop could have a lower rank than a node in the loop.
This causes issues when structurizing some patterns, and also codegen
issues as we could generate BBs in the incorrect order in regard to the
SPIR-V spec.

Fixing this ordering alone broke other parts of the structurizer, which
by luck worked. Had to fix those.

Added more test cases, especially to test basic patterns.

I also needed to tweak/disable some tests for 2 reasons:
 - SPIR-V now required reg2mem/mem2reg to run. Meaning dead stores
   are optimized away. Some tests require tweaks to avoid having the
   whole function removed.
 - Mem2Reg will generate variable & load/stores. This generates
   G_BITCAST in several cases. And there is currently something wrong
   we do with G_BITCAST which causes MIR verifier to complain.
   Until this is resolved, I disabled -verify-machineinstrs flag on
   those tests.

---------

Signed-off-by: Nathan Gauër <brioche@google.com>