[GSoC] Add PolyhedralInfo pass - new interface to polly analysis

  Adding a new pass PolyhedralInfo. This pass will be the interface to Polly.
  Initially, we will provide the following interface:
    - #IsParallel(Loop *L) - return a bool depending on whether the loop is
                             parallel or not for the given program order.

Patch by Utpal Bora <cs14mtech11017@iith.ac.in>

Differential Revision: https://reviews.llvm.org/D21486

llvm-svn: 276637

1 files changed, 101 insertions, 0 deletions

diff --git a/polly/include/polly/PolyhedralInfo.h b/polly/include/polly/PolyhedralInfo.h
new file mode 100644
index 00000000000..3f2d6a39a66
--- /dev/null
+++ b/polly/include/polly/PolyhedralInfo.h
@@ -0,0 +1,101 @@
+//===- polly/PolyhedralInfo.h - PolyhedralInfo class definition -*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+///
+/// This file contains the declaration of the PolyhedralInfo class, which will
+/// provide an interface to expose polyhedral analysis information of Polly.
+///
+/// This is work in progress. We will add more API's as an when deemed required.
+//===----------------------------------------------------------------------===///
+
+#ifndef POLLY_POLYHEDRAL_INFO_H
+#define POLLY_POLYHEDRAL_INFO_H
+
+#include "llvm/Pass.h"
+#include "isl/ctx.h"
+#include "isl/union_map.h"
+
+namespace llvm {
+class Loop;
+}
+
+namespace polly {
+
+class Scop;
+class ScopInfoWrapperPass;
+class DependenceInfoWrapperPass;
+
+class PolyhedralInfo : public llvm::FunctionPass {
+public:
+  static char ID; // Pass identification, replacement for typeid
+
+  /// @brief Construct a new PolyhedralInfo pass.
+  PolyhedralInfo() : FunctionPass(ID) {}
+  ~PolyhedralInfo() {}
+
+  /// @brief   Check if a given loop is parallel.
+  ///
+  /// @param L The loop.
+  ///
+  /// @return  Returns true, if loop is parallel false otherwise.
+  bool isParallel(llvm::Loop *L) const;
+
+  /// @brief   Return the SCoP containing the @p L loop.
+  ///
+  /// @param L The loop.
+  ///
+  /// @return  Returns the SCoP containing the given loop.
+  ///          Returns null if the loop is not contained in any SCoP.
+  const Scop *getScopContainingLoop(llvm::Loop *L) const;
+
+  /// @brief   Computes the partial schedule for the given @p L loop.
+  ///
+  /// @param S The SCoP containing the given loop
+  /// @param L The loop.
+  ///
+  /// @return  Returns the partial schedule for the given loop
+  __isl_give isl_union_map *getScheduleForLoop(const Scop *S,
+                                               llvm::Loop *L) const;
+
+  /// @brief Get the SCoP and dependence analysis information for @p F.
+  bool runOnFunction(llvm::Function &F) override;
+
+  /// @brief Release the internal memory.
+  void releaseMemory() override {}
+
+  /// @brief Print to @p OS if each dimension of a loop nest is parallel or not.
+  void print(llvm::raw_ostream &OS,
+             const llvm::Module *M = nullptr) const override;
+
+  /// @brief Register all analyses and transformation required.
+  void getAnalysisUsage(llvm::AnalysisUsage &AU) const override;
+
+private:
+  /// @brief   Check if a given loop is parallel or vectorizable.
+  ///
+  /// @param L             The loop.
+  /// @param MinDepDistPtr If not nullptr, the minimal dependence distance will
+  ///                      be returned at the address of that pointer
+  ///
+  /// @return  Returns true if loop is parallel or vectorizable, false
+  ///          otherwise.
+  bool checkParallel(llvm::Loop *L,
+                     __isl_give isl_pw_aff **MinDepDistPtr = nullptr) const;
+
+  ScopInfoWrapperPass *SI;
+  DependenceInfoWrapperPass *DI;
+};
+
+} // end namespace polly
+
+namespace llvm {
+class PassRegistry;
+void initializePolyhedralInfoPass(llvm::PassRegistry &);
+}
+
+#endif