[PATCH] D54366: RegAllocFast: Add heuristic to detect values not live-out of a block

[Matt Arsenault via Phabricator via llvm-commits]

arsenm added inline comments.


================
Comment at: lib/CodeGen/RegAllocFast.cpp:273
+    return false;
+  const MachineBasicBlock *FirstMBB = I->getParent()->getParent();
+
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I think this approach doesn't work because once the virtual register is rewritten in one block, it no longer appears in the vreg's use list in the next block


Repository:
  rL LLVM

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D54366/new/

https://reviews.llvm.org/D54366