[polly] r255500 - Add unit test for r255473

[Michael Kruse via llvm-commits]

Author: meinersbur
Date: Mon Dec 14 08:53:30 2015
New Revision: 255500

URL: http://llvm.org/viewvc/llvm-project?rev=255500&view=rev
Log:
Add unit test for r255473

Check that memory accesses in non-affine regions that are always executed are
MUST_WRITE.

Added:
    polly/trunk/test/ScopInfo/NonAffine/non_affine_region_guaranteed_non-entry.ll

Added: polly/trunk/test/ScopInfo/NonAffine/non_affine_region_guaranteed_non-entry.ll
URL: http://llvm.org/viewvc/llvm-project/polly/trunk/test/ScopInfo/NonAffine/non_affine_region_guaranteed_non-entry.ll?rev=255500&view=auto
==============================================================================
--- polly/trunk/test/ScopInfo/NonAffine/non_affine_region_guaranteed_non-entry.ll (added)
+++ polly/trunk/test/ScopInfo/NonAffine/non_affine_region_guaranteed_non-entry.ll Mon Dec 14 08:53:30 2015
@@ -0,0 +1,51 @@
+; RUN: opt %loadPolly -polly-detect -polly-scops -analyze < %s | FileCheck %s
+
+; The BasicBlock "guaranteed" is always executed inside the non-affine subregion
+; region_entry->region_exit. As such, writes accesses in blocks that always
+; execute are MustWriteAccesses. Before Polly commit r255473, we only assumed
+; that the subregion's entry block is guaranteed to execute.
+
+; CHECK-NOT: MayWriteAccess
+; CHECK:      MustWriteAccess :=  [Reduction Type: NONE] [Scalar: 0]
+; CHECK-NEXT:     { Stmt_region_entry__TO__region_exit[i0] -> MemRef_A[0] };
+; CHECK-NOT: MayWriteAccess
+
+define void @f(i32* %A, float %b) {
+entry:
+  br label %for.cond
+
+for.cond:
+  %indvar = phi i32 [ %indvar.next, %for.inc ], [ 0, %entry ]
+  %exitcond = icmp ne i32 %indvar, 1024
+  br i1 %exitcond, label %region_entry, label %return
+
+region_entry:
+  %cond_entry = fcmp oeq float %b, 3.0
+  br i1 %cond_entry, label %bb2, label %bb3
+
+bb2:
+  br label %guaranteed
+
+bb3:
+  br label %guaranteed
+
+guaranteed:
+  store i32 0, i32* %A
+  br i1 %cond_entry, label %bb5, label %bb6
+
+bb5:
+  br label %region_exit
+
+bb6:
+  br i1 %cond_entry, label %region_exit, label %bb3
+
+region_exit:
+  br label %for.inc
+
+for.inc:
+  %indvar.next = add i32 %indvar, 1
+  br label %for.cond
+
+return:
+  ret void
+}