Align copied load/store instructions as the original.

  This also forbids the json importer to access other memory locations
  than the original instruction as we to reuse the alignment of the
  original load/store.

Differential Revision: http://reviews.llvm.org/D5560

llvm-svn: 218883

1 files changed, 15 insertions, 0 deletions

diff --git a/polly/lib/Exchange/JSONExporter.cpp b/polly/lib/Exchange/JSONExporter.cpp
index d3aebfa72c7..36e302b1522 100644
--- a/polly/lib/Exchange/JSONExporter.cpp
+++ b/polly/lib/Exchange/JSONExporter.cpp
@@ -277,6 +277,21 @@ bool JSONImporter::runOnScop(Scop &scop) {
         return false;
       }
 
+      // We keep the old alignment, thus we cannot allow accesses to memory
+      // locations that were not accessed before.
+      isl_set *newAccessSet = isl_map_range(isl_map_copy(newAccessMap));
+      isl_set *currentAccessSet = isl_map_range(isl_map_copy(currentAccessMap));
+      bool isSubset = isl_set_is_subset(newAccessSet, currentAccessSet);
+      isl_set_free(newAccessSet);
+      isl_set_free(currentAccessSet);
+
+      if (!isSubset) {
+        errs() << "JScop file changes the accessed memory\n";
+        isl_map_free(currentAccessMap);
+        isl_map_free(newAccessMap);
+        return false;
+      }
+
       // We need to copy the isl_ids for the parameter dimensions to the new
       // map. Without doing this the current map would have different
       // ids then the new one, even though both are named identically.