[llvm] [X86][AsmParser] Improve rel8 validation (PR #126073)

[Phoebe Wang via llvm-commits]

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@@ -825,6 +828,11 @@ fucomip st, st(2)
 // CHECK: fcompi  %st(2)
 // CHECK: fucompi  %st(2)
 
+jrcxz _nop_label
+jecxz _nop_label + 1
+// CHECK: jrcxz _nop_label
+// CHECK: jecxz _nop_label+1
+
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phoebewang wrote:

Add positive test for Imm8?

https://github.com/llvm/llvm-project/pull/126073