[PATCH] D149977: [RISCV] Implement shouldTransformSignedTruncationCheck.

[Craig Topper via Phabricator via llvm-commits]

craig.topper created this revision.
craig.topper added reviewers: asb, dtcxzyw, reames, luismarques.
Herald added subscribers: jobnoorman, luke, VincentWu, vkmr, frasercrmck, evandro, apazos, sameer.abuasal, s.egerton, Jim, benna, psnobl, jocewei, PkmX, the_o, brucehoult, MartinMosbeck, rogfer01, edward-jones, zzheng, jrtc27, shiva0217, kito-cheng, niosHD, sabuasal, simoncook, johnrusso, rbar, hiraditya, arichardson.
Herald added a project: All.
craig.topper requested review of this revision.
Herald added subscribers: pcwang-thead, eopXD, MaskRay.
Herald added a project: LLVM.

This helps avoid constant materialization for the patterns
InstCombine emits for something like INT_MIN <= X && x <= INT_MAX.

See top of changed test files for more detailed explanation.

I've enabled this for i16 when Zbb is enabled. sext.b did not seem
to be a benefit due to the constants folding into addi/sltiu.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D149977

Files:
  llvm/lib/Target/RISCV/RISCVISelLowering.cpp
  llvm/lib/Target/RISCV/RISCVISelLowering.h
  llvm/test/CodeGen/RISCV/lack-of-signed-truncation-check.ll
  llvm/test/CodeGen/RISCV/signed-truncation-check.ll

-------------- next part --------------
A non-text attachment was scrubbed...
Name: D149977.519932.patch
Type: text/x-patch
Size: 18837 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20230505/ef821176/attachment.bin>