[PATCH] D52975: [TargetLowering][RISCV] Introduce getExtendForShiftAmount and implement for RISC-V

[Eli Friedman via Phabricator via llvm-commits]

efriedma requested changes to this revision.
efriedma added a comment.
This revision now requires changes to proceed.

You can't ANY_EXTEND here; that will confuse DAGCombine, which will, for example, fold shifts where the shift amount is too large to undef.  Other targets normally deal with this at isel time; see, for example, MaskedShiftAmountPats in lib/Target/X86/X86InstrCompiler.td .


https://reviews.llvm.org/D52975