[llvm] [AArch64][SME] Lower memchr to __arm_sc_memchr in streaming[-compatible] functions (PR #168896)

[Benjamin Maxwell via llvm-commits]

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@@ -156,29 +156,35 @@ SDValue AArch64SelectionDAGInfo::EmitMOPS(unsigned Opcode, SelectionDAG &DAG,
 }
 
 SDValue AArch64SelectionDAGInfo::EmitStreamingCompatibleMemLibCall(
-    SelectionDAG &DAG, const SDLoc &DL, SDValue Chain, SDValue Dst, SDValue Src,
+    SelectionDAG &DAG, const SDLoc &DL, SDValue Chain, SDValue Op0, SDValue Op1,
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MacDue wrote:

Because the meaning of `Op0` and `Op1` depend on the libcall (for `memchr` it would be `Ptr` and `Chr`). So, I switched them to something generic to avoid confusion. 

https://github.com/llvm/llvm-project/pull/168896