[PATCH] D54346: [SelectionDAG][X86] Relax restriction on the width of an input to *_EXTEND_VECTOR_INREG. Use them and regular *_EXTEND to replace the X86 specific VSEXT/VZEXT opcodes

[Craig Topper via Phabricator via llvm-commits]

craig.topper added inline comments.


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Comment at: lib/Target/X86/X86ISelLowering.cpp:40087
     SmallVector<APInt, 4> Vals(NumElts, APInt(EltSizeInBits, 0));
-    bool IsZEXT =
-        (Opcode == X86ISD::VZEXT) || (Opcode == ISD::ZERO_EXTEND_VECTOR_INREG);
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I just flipped this in case we ever wanted to send ANY_EXTEND_VECTOR_INREG in here.


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Comment at: lib/Target/X86/X86ISelLowering.cpp:40100
 
-  // (vzext (bitcast (vzext (x)) -> (vzext x)
-  // TODO: (vsext (bitcast (vsext (x)) -> (vsext x)
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It seems this code is unnecessary either due to this change or before this change. I didn't check which. I removed it assuming I'd need to put some of it back when tests failed but nothing did so I left it out.


https://reviews.llvm.org/D54346