[PATCH] D129932: [AArch64] Use SUBXrx64 for dynamic stack to refer to sp

[Eli Friedman via Phabricator via llvm-commits]

efriedma added inline comments.


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Comment at: llvm/lib/Target/AArch64/AArch64ISelLowering.cpp:12250
+  Chain = SP.getValue(1);
+  SP = SDValue(DAG.getMachineNode(AArch64::SUBXrx64, dl, MVT::i64, SP, Size,
+                                  ArithExtImm),
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Please don't use getMachineNode outside of actual instruction selection (AArch64ISelDAGToDAG).  It sort of works, but it breaks the relationship between the lowering and instruction selection, so it can have confusing effects.  Instead, add an opcode to AArch64ISelLowering.h.  (I know this hasn't been followed consistently in the past, but I'd prefer not to expand the existing usage.)


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D129932/new/

https://reviews.llvm.org/D129932