[PATCH] D138082: GlobalISel: ComputeNumSignBits from load range metadata

[Jay Foad via Phabricator via llvm-commits]

foad added inline comments.


================
Comment at: llvm/lib/CodeGen/GlobalISel/GISelKnownBits.cpp:633
+  if (TyBits != CR.getBitWidth())
+    return 1;
+
----------------
Can this just go in the `default` case above?


================
Comment at: llvm/lib/CodeGen/GlobalISel/GISelKnownBits.cpp:692
+    GLoad *Ld = cast<GLoad>(&MI);
+    if (DemandedElts != 1)
+      break;
----------------
What exactly is this check for?


================
Comment at: llvm/lib/CodeGen/GlobalISel/GISelKnownBits.cpp:630
+  if (TyBits != CR.getBitWidth())
+    return 1;
+
----------------
arsenm wrote:
> foad wrote:
> > How could we hit this?
> The anyextload case (or if the metadata was on a casted to vector result type)
I don't understand the "casted to vector" case - is there a test case for that?


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D138082/new/

https://reviews.llvm.org/D138082