[llvm] [DAG] Precommit tests for computeKnownFPClass - ISD::EXTRACT_SUBVECTOR and ISD::INSERT_SUBVECTOR. (PR #190694)

[Simon Pilgrim via llvm-commits]

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@@ -52,43 +52,115 @@ define <vscale x 2 x i1> @splat_constant_f64_isinf_false() {
   ret <vscale x 2 x i1> %res
 }
 
-define <4 x i1> @fneg_vec_not_negative(<4 x i32> %vecbits) nounwind {
-; CHECK-LABEL: fneg_vec_not_negative:
+define <vscale x 4 x i1> @extract_subvec_scalable(<vscale x 8 x float> %a0) {
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RKSimon wrote:

Ensure all the new test names indicate the fpclass test you're doing:
e.g.
```suggestion
define <vscale x 4 x i1> @extract_subvec_scalable_isneg_false(<vscale x 8 x float> %a0) {
```

https://github.com/llvm/llvm-project/pull/190694