[PATCH] D143182: CodeGen: Optimize lowering of is.fpclass fcZero|fcSubnormal

[Serge Pavlov via Phabricator via llvm-commits]

sepavloff added inline comments.


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Comment at: llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp:7362
   LLT SrcTy = MRI.getType(SrcReg);
   uint64_t Mask = MI.getOperand(2).getImm();
 
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Using `FPClassTest` may simplify the implementation a bit.


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Comment at: llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp:7375
 
+  // TODO: Try getInvertedFPClassTest
+
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This TODO does not look clear enough.


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Comment at: llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp:7438
+                                       ExpBits, ZeroC));
+      Mask &= ~PartialCheck & fcAllFlags;
+    }
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If `Mask` is `FPClassTest`, `&  fcAllFlags` is superfluous.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D143182/new/

https://reviews.llvm.org/D143182