[llvm] AMDGPU: Migrate more tests away from undef (PR #131314)

[Matt Arsenault via llvm-commits]

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@@ -128,13 +128,40 @@ define void @bitset_verifier_error() local_unnamed_addr #0 {
 ; SI-NEXT:  ; %bb.1: ; %bb5
 ; SI-NEXT:  .LBB6_2: ; %bb6
 bb:
-  %i = call float @llvm.fabs.f32(float undef) #0
+  %undef0 = freeze float poison
+  %i = call float @llvm.fabs.f32(float %undef0) #0
   %i1 = bitcast float %i to i32
   store i32 %i1, ptr addrspace(1) @gv
   br label %bb2
 
 bb2:
-  %i3 = call float @llvm.fabs.f32(float undef) #0
+  %undef1 = freeze float poison
+  %i3 = call float @llvm.fabs.f32(float %undef1) #0
+  %i4 = fcmp fast ult float %i3, 0x3FEFF7CEE0000000
+  br i1 %i4, label %bb5, label %bb6
+
+bb5:
+  unreachable
+
+bb6:
+  unreachable
+}
+
+define void @bitset_verifier_error_poison() local_unnamed_addr #0 {
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arsenm wrote:

I'm trying to avoid unrelated test changes here 

https://github.com/llvm/llvm-project/pull/131314