[llvm] [RISCV][GlobalISel] Legalize Scalable Vector Loads and Stores (PR #84965)

[Michael Maitland via llvm-commits]

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@@ -651,6 +687,62 @@ bool RISCVLegalizerInfo::legalizeExt(MachineInstr &MI,
   return true;
 }
 
+bool RISCVLegalizerInfo::legalizeLoadStore(MachineInstr &MI,
+                                           LegalizerHelper &Helper,
+                                           MachineIRBuilder &MIB) const {
+  MachineRegisterInfo &MRI = *MIB.getMRI();
+  MachineFunction *MF = MI.getMF();
+  const DataLayout &DL = MIB.getDataLayout();
+  LLVMContext &Ctx = MF->getFunction().getContext();
+
+  Register DstReg = MI.getOperand(0).getReg();
+  Register PtrReg = MI.getOperand(1).getReg();
+  LLT DataTy = MRI.getType(DstReg);
+  if (!DataTy.isVector())
+    return false;
+
+  if (!(STI.hasVInstructions() &&
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michaelmaitland wrote:

Should we move this into the `customIf` statement? We know this information at the time of `customIf`. This stuff does not depend on `MI`.

https://github.com/llvm/llvm-project/pull/84965