3 files changed, 81 insertions, 0 deletions
diff --git a/llvm/test/Transforms/ADCE/2017-08-21-DomTree-deletions.ll b/llvm/test/Transforms/ADCE/2017-08-21-DomTree-deletions.ll
new file mode 100644
index 00000000000..e532f29e9f4
--- /dev/null
+++ b/llvm/test/Transforms/ADCE/2017-08-21-DomTree-deletions.ll
@@ -0,0 +1,24 @@
+; RUN: opt < %s -adce | llvm-dis
+; RUN: opt < %s -adce -verify-dom-info | llvm-dis
+
+define void @foo() {
+entry:
+  br label %switch
+switch:                    ; preds = %entry
+  switch i32 undef, label %default [
+    i32 2, label %two
+    i32 5, label %five
+    i32 4, label %four
+  ]
+four:                      ; preds = %switch
+  br label %exit
+five:                      ; preds = %switch
+  br label %exit
+two:                       ; preds = %switch
+  br label %exit
+default:                   ; preds = %switch
+  br label %exit
+exit:                      ; preds = %default, %two, %five, %four
+  ret void
+}
+
diff --git a/llvm/test/Transforms/ADCE/domtree-DoubleDeletion.ll b/llvm/test/Transforms/ADCE/domtree-DoubleDeletion.ll
new file mode 100644
index 00000000000..018eb79b26f
--- /dev/null
+++ b/llvm/test/Transforms/ADCE/domtree-DoubleDeletion.ll
@@ -0,0 +1,39 @@
+; RUN: opt < %s -gvn -simplifycfg -adce | llvm-dis
+; RUN: opt < %s -gvn -simplifycfg -adce -verify-dom-info | llvm-dis
+
+; This test makes sure that the DominatorTree properly handles
+; deletion of edges that go to forward-unreachable regions.
+; In this case, %land.end is already forward unreachable when
+; the DT gets informed about the deletion of %entry -> %land.end.
+
+@a = common global i32 0, align 4
+
+define i32 @main() {
+entry:
+  %retval = alloca i32, align 4
+  store i32 0, i32* %retval, align 4
+  %0 = load i32, i32* @a, align 4
+  %cmp = icmp ne i32 %0, 1
+  br i1 %cmp, label %land.rhs, label %land.end4
+
+land.rhs:                                         ; preds = %entry
+  %1 = load i32, i32* @a, align 4
+  %tobool = icmp ne i32 %1, 0
+  br i1 %tobool, label %land.rhs1, label %land.end
+
+land.rhs1:                                        ; preds = %land.rhs
+  br label %land.end
+
+land.end:                                         ; preds = %land.rhs1, %land.rhs
+  %2 = phi i1 [ false, %land.rhs ], [ true, %land.rhs1 ]
+  %land.ext = zext i1 %2 to i32
+  %conv = trunc i32 %land.ext to i16
+  %conv2 = sext i16 %conv to i32
+  %tobool3 = icmp ne i32 %conv2, 0
+  br label %land.end4
+
+land.end4:                                        ; preds = %land.end, %entry
+  %3 = phi i1 [ false, %entry ], [ %tobool3, %land.end ]
+  %land.ext5 = zext i1 %3 to i32
+  ret i32 0
+}
diff --git a/llvm/test/Transforms/ADCE/unreachable.ll b/llvm/test/Transforms/ADCE/unreachable.ll
new file mode 100644
index 00000000000..aaacc184225
--- /dev/null
+++ b/llvm/test/Transforms/ADCE/unreachable.ll
@@ -0,0 +1,18 @@
+; RUN: opt < %s -adce -simplifycfg | llvm-dis
+; RUN: opt < %s -passes=adce | llvm-dis
+
+define i32 @Test(i32 %A, i32 %B) {
+BB1:
+        br label %BB4
+
+BB2:            ; No predecessors!
+        br label %BB3
+
+BB3:            ; preds = %BB4, %BB2
+        %ret = phi i32 [ %X, %BB4 ], [ %B, %BB2 ]               ; <i32> [#uses=1]
+        ret i32 %ret
+
+BB4:            ; preds = %BB1
+        %X = phi i32 [ %A, %BB1 ]               ; <i32> [#uses=1]
+        br label %BB3
+}