[ScheduleOptimizer] Make matmul pattern detection work with delicm output

In certain cases delicm might decide to not leave the original array write in
the loop body, but to remove it and instead leave a transformed phi node as
write access. This commit teached the matmul pattern detection to order the
memory accesses according to when the access actually happens and use this
information to detect the new pattern. This makes pattern based matmul
optimization work for 2mm and 3mm in polybench 4 after
polly-position=before-vectorizer has been enabled.

llvm-svn: 310338

1 files changed, 21 insertions, 33 deletions

diff --git a/polly/lib/Transform/Simplify.cpp b/polly/lib/Transform/Simplify.cpp
index 6f8a27f46e6..e172d839b03 100644
--- a/polly/lib/Transform/Simplify.cpp
+++ b/polly/lib/Transform/Simplify.cpp
@@ -98,39 +98,6 @@ static isl::union_map underapproximatedAddMap(isl::union_map UMap,
   return UResult;
 }
 
-/// Return a vector that contains MemoryAccesses in the order in
-/// which they are executed.
-///
-/// The order is:
-/// - Implicit reads (BlockGenerator::generateScalarLoads)
-/// - Explicit reads and writes (BlockGenerator::generateArrayLoad,
-///   BlockGenerator::generateArrayStore)
-///   - In block statements, the accesses are in order in which their
-///     instructions are executed.
-///   - In region statements, that order of execution is not predictable at
-///     compile-time.
-/// - Implicit writes (BlockGenerator::generateScalarStores)
-///   The order in which implicit writes are executed relative to each other is
-///   undefined.
-static SmallVector<MemoryAccess *, 32> getAccessesInOrder(ScopStmt &Stmt) {
-
-  SmallVector<MemoryAccess *, 32> Accesses;
-
-  for (MemoryAccess *MemAcc : Stmt)
-    if (isImplicitRead(MemAcc))
-      Accesses.push_back(MemAcc);
-
-  for (MemoryAccess *MemAcc : Stmt)
-    if (isExplicitAccess(MemAcc))
-      Accesses.push_back(MemAcc);
-
-  for (MemoryAccess *MemAcc : Stmt)
-    if (isImplicitWrite(MemAcc))
-      Accesses.push_back(MemAcc);
-
-  return Accesses;
-}
-
 class Simplify : public ScopPass {
 private:
   /// The last/current SCoP that is/has been processed.
@@ -700,6 +667,27 @@ public:
 char Simplify::ID;
 } // anonymous namespace
 
+namespace polly {
+SmallVector<MemoryAccess *, 32> getAccessesInOrder(ScopStmt &Stmt) {
+
+  SmallVector<MemoryAccess *, 32> Accesses;
+
+  for (MemoryAccess *MemAcc : Stmt)
+    if (isImplicitRead(MemAcc))
+      Accesses.push_back(MemAcc);
+
+  for (MemoryAccess *MemAcc : Stmt)
+    if (isExplicitAccess(MemAcc))
+      Accesses.push_back(MemAcc);
+
+  for (MemoryAccess *MemAcc : Stmt)
+    if (isImplicitWrite(MemAcc))
+      Accesses.push_back(MemAcc);
+
+  return Accesses;
+}
+} // namespace polly
+
 Pass *polly::createSimplifyPass() { return new Simplify(); }
 
 INITIALIZE_PASS_BEGIN(Simplify, "polly-simplify", "Polly - Simplify", false,