[PATCH] D81993: [AArch64][GlobalISel] Add post-legalize combine for sext(trunc(sextload)) -> trunc/copy

[Matt Arsenault via Phabricator via llvm-commits]

arsenm added inline comments.


================
Comment at: llvm/lib/CodeGen/GlobalISel/CombinerHelper.cpp:588
+    LoadUser = TruncSrc;
+
+  uint64_t SizeInBits = MI.getOperand(2).getImm();
----------------
This is just a special case of checking computeNumSignBits? Do we recognize the number of sign bits in a sextload yet?


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D81993/new/

https://reviews.llvm.org/D81993