[test] Add test case for -polly-simplify. NFC.

llvm-svn: 309458

polly/test/Simplify/notdead_region_exitphi.ll

@@ -0,0 +1,44 @@
+; RUN: opt %loadPolly -polly-simplify -analyze < %s | FileCheck %s -match-full-lines
+;
+; Do not remove dependencies of a phi node in a region's exit block.
+;
+define void @func(i32 %n, double* noalias nonnull %A, double %alpha) {
+entry:
+  br label %for
+
+for:
+  %j = phi i32 [0, %entry], [%j.inc, %inc]
+  %j.cmp = icmp slt i32 %j, %n
+  br i1 %j.cmp, label %body, label %exit
+
+    body:
+      %val = fadd double 21.0, 21.0
+      br label %region_entry
+
+
+    region_entry:
+      %region.cmp = fcmp ueq double %alpha, 0.0
+      br i1 %region.cmp, label %region_true, label %region_exit
+
+    region_true:
+      br label %region_exit
+
+    region_exit:
+      %phi = phi double [%val, %region_true], [0.0, %region_entry]
+      store double %phi, double* %A
+      br label %inc
+
+
+inc:
+  %j.inc = add nuw nsw i32 %j, 1
+  br label %for
+
+exit:
+  br label %return
+
+return:
+  ret void
+}
+
+
+; CHECK: SCoP could not be simplified