[llvm] [llvm] Remove `br i1 undef` from regression tests (PR #117292)

[Nuno Lopes via llvm-commits]

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@@ -4,23 +4,26 @@ target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
 target triple = "x86_64-apple-macosx10.12.0"
 
 ; Function Attrs: nounwind ssp uwtable
-define void @reorder_ref_pic_list() local_unnamed_addr {
+define void @reorder_ref_pic_list(i1 %arg) local_unnamed_addr {
 ; CHECK-LABEL: @reorder_ref_pic_list(
 ; CHECK-NEXT:  entry:
-; CHECK-NEXT:    br i1 undef, label [[FOR_END:%.*]], label [[FOR_BODY_PREHEADER:%.*]]
+; CHECK-NEXT:    br i1 [[ARG:%.*]], label [[FOR_END:%.*]], label [[FOR_BODY_PREHEADER:%.*]]
 ; CHECK:       for.body.preheader:
 ; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
 ; CHECK:       for.body:
 ; CHECK-NEXT:    [[REFIDXLX_0:%.*]] = phi i32 [ [[INC_I51:%.*]], [[IF_ELSE58:%.*]] ], [ 0, [[FOR_BODY_PREHEADER]] ]
-; CHECK-NEXT:    br i1 undef, label [[IF_THEN13:%.*]], label [[IF_ELSE58]]
+; CHECK-NEXT:    br i1 false, label [[IF_THEN13:%.*]], label [[IF_ELSE58]]
 ; CHECK:       if.then13:
-; CHECK-NEXT:    [[INC_I:%.*]] = add nsw i32 [[REFIDXLX_0]], 1
+; CHECK-NEXT:    store i8 poison, ptr null, align 1
 ; CHECK-NEXT:    br label [[FOR_BODY8_I:%.*]]
 ; CHECK:       for.body8.i:
-; CHECK-NEXT:    br i1 undef, label [[FOR_INC24_I:%.*]], label [[IF_THEN17_I:%.*]]
+; CHECK-NEXT:    store i8 poison, ptr null, align 1
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nunoplopes wrote:

use different %args so this BB doesn't become unreachable

https://github.com/llvm/llvm-project/pull/117292