check that we only insert one phi node per loop

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@20503 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/test/Transforms/LoopStrengthReduce/dont_insert_redundant_ops.ll b/test/Transforms/LoopStrengthReduce/dont_insert_redundant_ops.ll
new file mode 100644 (file)
index 0000000..9d1b748
--- /dev/null
+++ b/test/Transforms/LoopStrengthReduce/dont_insert_redundant_ops.ll
@@ -0,0 +1,42 @@
+; Check that this test makes INDVAR and related stuff dead.
+; RUN: llvm-as < %s | opt -loop-reduce | llvm-dis | grep phi | wc -l | grep 2
+
+declare bool %pred()
+
+void %test({ int, int }* %P) {
+       br label %Loop
+Loop:
+       %INDVAR = phi int [0, %0], [%INDVAR2, %Loop]
+
+       %gep1 = getelementptr { int, int}* %P, int %INDVAR, uint 0
+       store int 0, int* %gep1
+
+       %gep2 = getelementptr { int, int}* %P, int %INDVAR, uint 1
+       store int 0, int* %gep2
+
+       %INDVAR2 = add int %INDVAR, 1
+       %cond = call bool %pred()
+       br bool %cond, label %Loop, label %Out
+Out:
+       ret void
+}
+
+declare bool %pred()
+
+void %test([2 x int]* %P) {
+       br label %Loop
+Loop:
+       %INDVAR = phi int [0, %0], [%INDVAR2, %Loop]
+
+       %gep1 = getelementptr [2 x int]* %P, int %INDVAR, uint 0
+       store int 0, int* %gep1
+
+       %gep2 = getelementptr [2 x int]* %P, int %INDVAR, uint 1
+       store int 0, int* %gep2
+
+       %INDVAR2 = add int %INDVAR, 1
+       %cond = call bool %pred()
+       br bool %cond, label %Loop, label %Out
+Out:
+       ret void
+}