[PATCH] D126885: [SLP]Cost for a constant buildvector.

[Alexey Bataev via Phabricator via llvm-commits]

ABataev added inline comments.


================
Comment at: llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp:5807
+          auto *CI = cast<ConstantInt>(V);
+          ScalarCost += TTI->getIntImmCostInst(
+              UserOpcode, UserIdx, CI->getValue(), ScalarTy, CostKind);
----------------
vdmitrie wrote:
> Isn't this interface already puts assumption that a constant is a legal immediate?
> I was trying to explore this too and I found that it does not seem to cover correctly 32bit target specifically for 64bit operations. Ideally we should have interface that tells whether immediate is a legal imm operand for a target but I have not found anything like that.
> One way to figure this (which I found -may be wrongful) is
>  when condition
>  DL->getTypeStoreSizeInBits(ScalarTy) >  DL->getLargestLegalIntTypeSizeInBits()
> is true we cannot assume operand as a legal immediate.
I'll check it.


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  https://reviews.llvm.org/D126885/new/

https://reviews.llvm.org/D126885