[PATCH] D109357: [GlobalISel] Add a combine for and(load , mask) -> zextload

[Konstantin Schwarz via Phabricator via llvm-commits]

kschwarz added inline comments.


================
Comment at: llvm/lib/CodeGen/GlobalISel/CombinerHelper.cpp:668
+  Register PtrReg = LoadMI->getPointerReg();
+  unsigned NewSize = std::min((uint64_t)MaskVal.countTrailingOnes(),
+                              LoadMI->getMemSizeInBits());
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foad wrote:
> This looks like it will combine:
> ```
>     %1:_(s32) = G_CONSTANT i32 65535
>     %2:_(s32) = G_SEXTLOAD %0 :: (load (s8))
>     %3:_(s32) = G_AND %2, %1
> ```
> into:
> ```
>     %2:_(s32) = G_ZEXTLOAD %0 :: (load (s8))
> ```
> which would be wrong.
Good catch, thanks!


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D109357/new/

https://reviews.llvm.org/D109357