[x86] add test check lines to demonstrate FMF propagation failure; NFC

Author: rotateright

llvm/test/CodeGen/X86/fmf-propagation.ll

@@ -48,8 +48,12 @@ define float @fmf_setcc_canon(float %x, float %y) {
 declare <16 x float> @llvm.x86.avx512.vfmadd.ps.512(<16 x float>, <16 x float>, <16 x float>, i32)
 
 ; CHECK-LABEL: Initial selection DAG: %bb.0 'fmf_target_intrinsic:'
-; CHECK: v16f32 = llvm.x86.avx512.vfmadd.ps.512 ninf nsz TargetConstant:i64<{{.*}}>
-; CHECK: v16f32 = llvm.x86.avx512.vfmadd.ps.512 nsz TargetConstant:i64<{{.*}}>
+; CHECK:       v16f32 = llvm.x86.avx512.vfmadd.ps.512 ninf nsz TargetConstant:i64<{{.*}}>
+; CHECK:       v16f32 = llvm.x86.avx512.vfmadd.ps.512 nsz TargetConstant:i64<{{.*}}>
+
+; CHECK-LABEL: Legalized selection DAG: %bb.0 'fmf_target_intrinsic:'
+; CHECK:       v16f32 = fma t{{.*}}
+; CHECK:       v16f32 = fma t{{.*}}
 
 define <16 x float> @fmf_target_intrinsic(<16 x float> %a, <16 x float> %b, <16 x float> %c) nounwind {
   %t0 = tail call ninf nsz <16 x float> @llvm.x86.avx512.vfmadd.ps.512(<16 x float> %a, <16 x float> %b, <16 x float> %c, i32 4)