Imported Upstream version 6.10.0.49

Former-commit-id: 1d6753294b2993e1fbf92de9366bb9544db4189b

external/llvm-project/llvm/test/Transforms/SimplifyCFG/2011-03-08-UnreachableUse.ll

@@ -0,0 +1,31 @@
+; RUN: opt < %s -simplifycfg -S | FileCheck %s
+; PR9420
+
+; Note that the crash in PR9420 test is sensitive to the ordering of
+; the transformations done by SimplifyCFG, so this test is likely to rot
+; quickly.
+
+define noalias i8* @func_29() nounwind {
+; CHECK: entry:
+; CHECK-NEXT: unreachable
+entry:
+  br label %for.cond
+
+for.cond:                                         ; preds = %for.inc38, %entry
+  %p_34.addr.0 = phi i16 [ 1, %entry ], [ %conv40, %for.inc38 ]
+  br label %for.cond1
+
+for.cond1:                                        ; preds = %for.inc29, %for.cond
+  %p_32.addr.0 = phi i1 [ true, %for.cond ], [ true, %for.inc29 ]
+  br i1 %p_32.addr.0, label %for.body8, label %for.inc38
+
+for.body8:                                        ; preds = %for.cond1
+  unreachable
+
+for.inc29:                                        ; preds = %for.cond17
+  br label %for.cond1
+
+for.inc38:                                        ; preds = %for.end32
+  %conv40 = add i16 %p_34.addr.0, 1
+  br label %for.cond
+}