[AArch64] Generate test checks (NFC)

Also mark the test as nounwind. The unwinding information does
not appear to be pertinent to the original intent of the test.

llvm/test/CodeGen/AArch64/windows-extern-weak.ll

@@ -1,23 +1,20 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
 ; RUN: llc -mtriple aarch64-windows -filetype asm -o - < %s | FileCheck %s
 ; RUN: llc -mtriple aarch64-windows -filetype asm -o - -fast-isel %s | FileCheck %s
 ; RUN: llc -mtriple aarch64-windows -filetype asm -o - -global-isel -global-isel-abort=0 %s | FileCheck %s
 
-define void @func() {
+define void @func() nounwind {
 ; CHECK-LABEL: func:
-; CHECK:      str x30, [sp, #-16]!
-; CHECK-NEXT: .seh_save_reg_x x30, 16
-; CHECK-NEXT: .seh_endprologue
-; CHECK-NEXT: adrp x8, .refptr.weakfunc
-; CHECK-NEXT: ldr x8, [x8, :lo12:.refptr.weakfunc]
-; CHECK-NEXT: cbz     x8, .LBB0_2
-; CHECK-NEXT: // %bb.1:
-; CHECK-NEXT: blr     x8
-; CHECK-NEXT: .LBB0_2:
-; CHECK-NEXT: .seh_startepilogue
-; CHECK-NEXT: ldr x30, [sp], #16
-; CHECK-NEXT: .seh_save_reg_x x30, 16
-; CHECK-NEXT: .seh_endepilogue
-; CHECK-NEXT: ret
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    str x30, [sp, #-16]! // 8-byte Folded Spill
+; CHECK-NEXT:    adrp x8, .refptr.weakfunc
+; CHECK-NEXT:    ldr x8, [x8, :lo12:.refptr.weakfunc]
+; CHECK-NEXT:    cbz x8, .LBB0_2
+; CHECK-NEXT:  // %bb.1:
+; CHECK-NEXT:    blr x8
+; CHECK-NEXT:  .LBB0_2:
+; CHECK-NEXT:    ldr x30, [sp], #16 // 8-byte Folded Reload
+; CHECK-NEXT:    ret
 
   br i1 icmp ne (ptr @weakfunc, ptr null), label %1, label %2