[PATCH] D95805: [AArch64][GlobalISel] Emit G_ASSERT_ZEXT in assignValueToAddress for ZExt params

[Jessica Paquette via Phabricator via llvm-commits]

paquette created this revision.
paquette added a reviewer: aemerson.
Herald added subscribers: danielkiss, hiraditya, kristof.beyls, rovka.
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When we have a zeroext parameter coming in on the stack, build

  %x = G_LOAD ...
  %x_assert_zext = G_ASSERT_ZEXT %x, narrow_size
  %trunc = G_TRUNC %x_assert_zext

Rather than just loading into the truncated type.

This allows us to optimize cases like this: https://godbolt.org/z/vfjhW8


https://reviews.llvm.org/D95805

Files:
  llvm/lib/Target/AArch64/GISel/AArch64CallLowering.cpp
  llvm/test/CodeGen/AArch64/GlobalISel/call-lowering-zeroext.ll

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