New testcase

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@8617 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/test/Transforms/TailCallElim/ackermann.ll b/test/Transforms/TailCallElim/ackermann.ll
new file mode 100644 (file)
index 0000000..fb71e88
--- /dev/null
+++ b/test/Transforms/TailCallElim/ackermann.ll
@@ -0,0 +1,29 @@
+; This function contains two tail calls, which should be eliminated
+; RUN: llvm-as < %s | opt -tailcallelim -stats -disable-output 2>&1 | grep '2 tailcallelim'
+
+int %Ack(int %M.1, int %N.1) {
+entry:
+        %tmp.1 = seteq int %M.1, 0              ; <bool> [#uses=1]
+        br bool %tmp.1, label %then.0, label %endif.0
+
+then.0:
+        %tmp.4 = add int %N.1, 1                ; <int> [#uses=1]
+        ret int %tmp.4
+
+endif.0:
+        %tmp.6 = seteq int %N.1, 0              ; <bool> [#uses=1]
+        br bool %tmp.6, label %then.1, label %endif.1
+
+then.1:
+        %tmp.10 = add int %M.1, -1              ; <int> [#uses=1]
+        %tmp.8 = call int %Ack( int %tmp.10, int 1 )            ; <int> [#uses=1]
+        ret int %tmp.8
+
+endif.1:
+        %tmp.13 = add int %M.1, -1              ; <int> [#uses=1]
+        %tmp.17 = add int %N.1, -1              ; <int> [#uses=1]
+        %tmp.14 = call int %Ack( int %M.1, int %tmp.17 )                ; <int> [#uses=1]
+        %tmp.11 = call int %Ack( int %tmp.13, int %tmp.14 )             ; <int> [#uses=1]
+        ret int %tmp.11
+}
+