[PATCH] D99507: [amdgpu] Add a pass to avoid jump into blocks with 0 exec mask.

[Jay Foad via Phabricator via llvm-commits]

foad added inline comments.


================
Comment at: llvm/lib/Target/AMDGPU/SIAvoidZeroExecMask.cpp:220
+  RS->enterBasicBlockEnd(MBB);
+  unsigned Scav = RS->scavengeRegisterBackwards(
+      AMDGPU::SReg_64RegClass, MachineBasicBlock::iterator(Cloned), false, 0);
----------------
What happens if there are no free sgprs so the scavenger has to spill something? That sounds like yet another case that won't work correctly when exec is zero.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D99507/new/

https://reviews.llvm.org/D99507