[PATCH] D77646: [PowerPC] Fold vector merges of swapped vectors to merge the opposite half

[Lei Huang via Phabricator via llvm-commits]

lei added inline comments.


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Comment at: llvm/lib/Target/PowerPC/PPCMIPeephole.cpp:287
+  unsigned Opc = MI->getOpcode();
+  switch (Opc) {
+  case PPC::VSPLTB:
----------------
Wondering if it would be good to add a flag in the td file to mark such instructions instead of listing them here.  That way when we add future instructions to the td file that will fall into this case, it'll be easier to see that is needed. 


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Comment at: llvm/lib/Target/PowerPC/PPCMIPeephole.cpp:701
+        unsigned NewOpc;
+        switch (MI.getOpcode()) {
+        case PPC::VMRGLB:
----------------
maybe add a `default: llvm_unreachable()` here?


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D77646/new/

https://reviews.llvm.org/D77646