[llvm] [RISCV][IA] Factor out code for extracting operands from mem insts [nfc] (PR #149344)

[Min-Yih Hsu via llvm-commits]

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@@ -102,6 +102,52 @@ static bool isMultipleOfN(const Value *V, const DataLayout &DL, unsigned N) {
   return false;
 }
 
+static bool getMemOperands(IRBuilderBase &Builder, unsigned Factor,
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mshockwave wrote:

maybe add a simple comment here to note that this function not only obtains memory operands but also does some simple validation (e.g. checking the mask)?

https://github.com/llvm/llvm-project/pull/149344