[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:

for reducing the number of function arguments, DataLayout could be obtained from the load instruction; I don't think we really need to pass in the IRBuilder here: we can just create a new local one inside this function using the load instruction as the insert point, since all the new instructions we'll insert here always go before the load instruction.

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