[PATCH] D34181: MachineInstr: Reason locally about some memory objects before going to AA.

[Geoff Berry via Phabricator via llvm-commits]

gberry added inline comments.


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Comment at: lib/CodeGen/MachineInstr.cpp:1664
+  int64_t WidthB = MMOb->getSize();
+  bool SameVal = MMOa->getValue() == MMOb->getValue();
+  if (!SameVal) {
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I don't think this is right since getValue() will return nullptr for any PseudoSourceValue, so SameVal will always be true for any two PseudoSourceValues, even if they are different.


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Comment at: lib/CodeGen/MachineInstr.cpp:1667
+    const PseudoSourceValue *PSVa = MMOa->getPseudoValue();
+    const PseudoSourceValue *PSVb = MMOb->getPseudoValue();
+    if (PSVa && PSVb && (PSVa == PSVb))
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I think the more interesting checks for PseudoValues are whether they can alias at all (i.e. PseudoSourceValue::isAliased/mayAlias), and if not they can only alias with themselves.


https://reviews.llvm.org/D34181