[X86] Add PR19752 test case

Test coverage for Issue #20126

Author: RKSimon

llvm/test/CodeGen/X86/pr19752.ll

@@ -0,0 +1,15 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc < %s | FileCheck %s
+
+target datalayout = "e-m:e-p:32:32-f64:32:64-f80:32-n8:16:32-S128"
+target triple = "i386---elf"
+
+define void @test() {
+; CHECK-LABEL: test:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    #APP
+; CHECK-NEXT:    movl %fs:0, %eax
+; CHECK-NEXT:    #NO_APP
+  %tmp = tail call i64 asm "movl %fs:${1:a}, ${0:k}", "=q,irm,~{dirflag},~{fpsr},~{flags}"(i64 0)
+  unreachable
+}