[PATCH] D56501: [WebAssembly] Add unimplemented-simd128 subtarget feature

[Heejin Ahn via Phabricator via llvm-commits]

aheejin added inline comments.


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Comment at: lib/Target/WebAssembly/WebAssemblyISelLowering.cpp:1108
+  // simpler in this file, but would necessitate large and brittle patterns to
+  // undo the expansion and select extract_lane_s instructions.
+  assert(!Subtarget->hasSignExt() && Subtarget->hasSIMD128());
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Hmm, the purpose of this comment is when other people who don't have any context of our discussions see this they would understand why it's done this way. I'm not sure if I can understand this if I'm not the one who had the discussion. At least I think we'd better to add that while simd128 feature does not requires signext feature's functionality, `signext_inreg` isel node allows us cleaner implementation of vector extract patterns in simd128, so we want to make use of that to implement the patterns even when signext feature is off.


Repository:
  rL LLVM

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D56501/new/

https://reviews.llvm.org/D56501