[CodeGen] Handle outlining of CopyStmts.

Since the removal of extensions nodes from schedule trees in r362257 it
is possible to emit parallel code for SCoPs containing
matrix-multiplications. However, the code looking for references used in
outlined statement was not prepared to handle CopyStmts introduced by
the matrix-matrix multiplication detection.

In this case, CopyStmts do not introduce references in addition to the
ones captured by MemoryAccesses, i.e. we change the assertion to accept
CopyStmts and add a regression test for this case.

This fixes llvm.org/PR43164

llvm-svn: 372188

1 files changed, 4 insertions, 3 deletions

diff --git a/polly/lib/CodeGen/IslNodeBuilder.cpp b/polly/lib/CodeGen/IslNodeBuilder.cpp
index 492944cf7c3..13d61694c54 100644
--- a/polly/lib/CodeGen/IslNodeBuilder.cpp
+++ b/polly/lib/CodeGen/IslNodeBuilder.cpp
@@ -231,11 +231,12 @@ void addReferencesFromStmt(const ScopStmt *Stmt, void *UserPtr,
 
   if (Stmt->isBlockStmt())
     findReferencesInBlock(References, Stmt, Stmt->getBasicBlock());
-  else {
-    assert(Stmt->isRegionStmt() &&
-           "Stmt was neither block nor region statement");
+  else if (Stmt->isRegionStmt()) {
     for (BasicBlock *BB : Stmt->getRegion()->blocks())
       findReferencesInBlock(References, Stmt, BB);
+  } else {
+    assert(Stmt->isCopyStmt());
+    // Copy Stmts have no instructions that we need to consider.
   }
 
   for (auto &Access : *Stmt) {