[MachineVerifier] Fix bug in MachineVerifier for G_INSERT_SUBVECTOR (llvm#109048)

Author: michaelmaitland

llvm/lib/CodeGen/MachineVerifier.cpp

@@ -1739,7 +1739,7 @@ void MachineVerifier::verifyPreISelGenericInstruction(const MachineInstr *MI) {
     }
 
     if (IndexOp.getImm() != 0 &&
-        Src1Ty.getElementCount().getKnownMinValue() % IndexOp.getImm() != 0) {
+        IndexOp.getImm() % Src1Ty.getElementCount().getKnownMinValue() != 0) {
       report("Index must be a multiple of the second source vector's "
              "minimum vector length",
              MI);

llvm/test/MachineVerifier/test_g_insert_subvector.mir

@@ -41,4 +41,7 @@ body:             |
 
     ; CHECK: Index must be a multiple of the second source vector's minimum vector length
     %13:_(<vscale x 4 x s32>) = G_INSERT_SUBVECTOR %12, %1, 3
+
+    ; CHECK: Index must be a multiple of the second source vector's minimum vector length
+    %13:_(<vscale x 4 x s32>) = G_INSERT_SUBVECTOR %12, %1, 1
 ...