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

[Michael Maitland via llvm-commits]

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@@ -649,6 +680,61 @@ bool RISCVLegalizerInfo::legalizeExt(MachineInstr &MI,
   return true;
 }
 
+bool RISCVLegalizerInfo::legalizeLoadStore(MachineInstr &MI,
+                                           MachineIRBuilder &MIB) const {
+  MachineRegisterInfo &MRI = *MIB.getMRI();
+  MachineFunction *MF = MI.getParent()->getParent();
+  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);
+  assert(DataTy.isVector() && "Expect vector load.");
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michaelmaitland wrote:

I think you want to `return false` in any of these cases instead of `assert`. Since you call `custom()` it is totally possible that there was a non-vector type that was not marked as legal that makes it in here. `assert` should only be used to check preconditions.

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