[PATCH] D124728: Allow pointer types for atomicrmw xchg

[Eli Friedman via Phabricator via llvm-commits]

efriedma added inline comments.


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Comment at: llvm/lib/AsmParser/LLParser.cpp:7459
+  if (!(Operation == AtomicRMWInst::Xchg && Val->getType()->isPointerTy())) {
+    unsigned Size = Val->getType()->getPrimitiveSizeInBits();
+    if (Size < 8 || (Size & (Size - 1)))
----------------
You can change this to get the size from the datalayout, instead of using getPrimitiveSizeInBits().  (Not that I really expect anyone to declare a non-power-of-two pointer type, but I don't think we actually forbid it.)


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Comment at: llvm/lib/CodeGen/AtomicExpandPass.cpp:290
+            (RMWI->getValOperand()->getType()->isFloatingPointTy() ||
+             RMWI->getValOperand()->getType()->isPointerTy())) {
           // TODO: add a TLI hook to control this so that each target can
----------------
Can we try to preserve the pointer type where possible?  cmpxchg can take a pointer.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D124728/new/

https://reviews.llvm.org/D124728