[PATCH] D90527: [GlobalISel] ComputeKnownBits - minimum leading/trailing zero bits in shifts (PR44526)

[Matt Arsenault via Phabricator via llvm-commits]

arsenm added inline comments.


================
Comment at: llvm/lib/CodeGen/GlobalISel/GISelKnownBits.cpp:388
   case TargetOpcode::G_SHL: {
     KnownBits RHSKnown;
+    computeKnownBitsImpl(MI.getOperand(1).getReg(), Known, DemandedElts,
----------------
I thought there was a move towards moving the shared implementation of these into KnownBits::. Is there a reason this needs to be repeated here?


================
Comment at: llvm/lib/CodeGen/GlobalISel/GISelKnownBits.cpp:396
+      case TargetOpcode::G_ASHR:
+        // No matter the shift amount, the leading signbits will remain.
+        if (Known.isNegative()) {
----------------
s/signbits/sign bits/


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D90527/new/

https://reviews.llvm.org/D90527