add a check for ISL codegen at configure time
llvm-svn: 156305
diff --git a/polly/lib/CodeGen/IslCodeGeneration.cpp b/polly/lib/CodeGen/IslCodeGeneration.cpp
new file mode 100644
index 0000000..51aaec7
--- /dev/null
+++ b/polly/lib/CodeGen/IslCodeGeneration.cpp
@@ -0,0 +1,21 @@
+//===------ IslCodeGeneration.cpp - Code generate the Scops using ISL. ----===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// The IslCodeGeneration pass takes a Scop created by ScopInfo and translates it
+// back to LLVM-IR using the ISL code generator.
+//
+// The Scop describes the high level memory behaviour of a control flow region.
+// Transformation passes can update the schedule (execution order) of statements
+// in the Scop. ISL is used to generate an abstract syntax tree that reflects
+// the updated execution order. This clast is used to create new LLVM-IR that is
+// computationally equivalent to the original control flow region, but executes
+// its code in the new execution order defined by the changed scattering.
+//
+//===----------------------------------------------------------------------===//
+