[PATCH] D80161: [CodeGen] Add support for multiple memory operands in MachineInstr::mayAlias

[Dave Green via Phabricator via llvm-commits]

dmgreen added inline comments.


================
Comment at: llvm/lib/CodeGen/MachineInstr.cpp:1280
+        int64_t LowWidth = (MinOffset == OffsetA) ? WidthA : WidthB;
+        return (MinOffset + LowWidth > MaxOffset);
+      }
----------------
Kayjukh wrote:
> dmgreen wrote:
> > It would seem incorrect to return false here now? Same for the pseudo values above.
> Yes, we should only return if the result is true. For the pseudo-values I guess we can just skip the checks entirely and only update the value of `SameVal`.
> It leads to more test cases failing because of instruction ordering. I will update the diff as soon as I fixed all of these.
If the code before worked with two mmo's, would it be possible to do something like:
  auto HasAlias = [](MMOa, MMOb) {
    old code as it was before return true/false;
  };

  for (auto &MMOa : memoperands()) {
    for (auto &MMOb : Other.memoperands()) {
      if (HasAlias(MMOa, MMOb))
        return true;
  return false;


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D80161/new/

https://reviews.llvm.org/D80161