[PATCH] D66580: [ARM] Fold VPNOT into vpt blocks

[Sam Parker via Phabricator via llvm-commits]

samparker added inline comments.


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Comment at: llvm/lib/Target/ARM/MVEVPTBlockPass.cpp:158
+
+    // Now that we have a list of instructions between MI and MBIter, adjust it
+    // to make sure that it is a valid block. Including making sure that any the
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I'm struggling to understand the looping and the logic here. Why is a simple walk forward over the instructions not enough? I'd expect to see some conditions being checked and then just break when an instruction no longer meets the criteria. For instance, why can't the checks for kills and defs be performed in the do-loop above?


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Comment at: llvm/lib/Target/ARM/MVEVPTBlockPass.cpp:167
+          });
+      // If we do not find a kill of VPR in the block reverse backwoods to the
+      // VPNOT. This is guarenteed to redef VPR (and won't be included in the
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typos: backwoods and guarenteed.


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  https://reviews.llvm.org/D66580/new/

https://reviews.llvm.org/D66580