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Copyright (c) 2017 Intel Corporation

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======================= end_copyright_notice ==================================*/
#pragma once

#include "Compiler/CodeGenPublic.h"

#include "common/LLVMWarningsPush.hpp"
#include <llvm/Pass.h>
#include <llvm/IR/InstVisitor.h>
#include <llvm/ADT/StringRef.h>
#include "common/LLVMWarningsPop.hpp"

#include <map>
namespace IGC
{
// Attributes for each __builtin_IB_atomic function.
//
//              bufType
//                 |
//       not used  V   op
//       |-------|---|---|
//    0 x 0 0 0 0 0 0 0 0 
//
typedef unsigned int OCLAtomicAttrs;

// A pass that walks over call instructions and replaces all __builtin_IB_atomic calls
// with corresponding GenISA intrinsics.
//
class ResolveOCLAtomics : public llvm::ModulePass, public llvm::InstVisitor<ResolveOCLAtomics>
{
public:
    // Pass identification, replacement for typeid
    static char ID;

    /// @brief  Constructor
    ResolveOCLAtomics();

    /// @brief  Destructor
    ~ResolveOCLAtomics() {}

    /// @brief  Provides name of pass
    virtual llvm::StringRef getPassName() const override
    {
        return "ResolveOCLAtomics";
    }

    // Entry point of the pass.
    virtual bool runOnModule(llvm::Module &M) override;

    // Call instructions visitor.
    void visitCallInst(llvm::CallInst &callInst);

    static const unsigned int ATTR_BUFFER_TYPE_SHIFT = 8;

protected:
    llvm::Module      *m_pModule;
    llvm::IntegerType *m_Int32Ty;
    bool               m_64bitPointer;
 
    // A map that keeps attributes for each "__builtin_IB_atomic_*" function name.
    std::map<llvm::StringRef, OCLAtomicAttrs>  m_AtomicDescMap;

    void initResolveOCLAtomics();

    /// @brief    Packs the given atomic operation and buffer type into "attributes" integer.
    /// @param    op        Atomic operation
    /// @param    bufType   Buffer Type
    /// @returns  Computed "attributes" integer.
    OCLAtomicAttrs genAtomicAttrs(AtomicOp op, BufferType bufType);

    /// @brief  Get the atomic operation for atomic function name.
    /// @param    name    The name of atomic intrinsic.
    /// @returns  The atomic operation.
    AtomicOp       getAtomicOp(llvm::StringRef name);

    /// @brief  Get the buffer type for atomic function name.
    /// @param    name    The name of atomic intrinsic.
    /// @returns  The buffer type.
    BufferType     getBufType(llvm::StringRef name);

    /// @brief  Initialize the "atomic name <--> attributes" map.
    void           initOCLAtomicsMap();

    /// @brief  Replace the "__builtin_IB_atomic_*" call with a call to GenISA atomic intrinsic.
    /// @param    callInst  call to "__builtin_IB_atomic_*" function.
    /// @param    op        atomic operation.
    /// @param    bufType   buffer type.
    void           processOCLAtomic(llvm::CallInst &callInst, AtomicOp op, BufferType bufType);

    /// @brief  Generates a call to "GenISA_GetBufferPtr" intrinsic.
    /// @param    callInst   call instruction to "__builtin_IB_atomic_*" built-in function.
    /// @param    bufType    corresponding buffer type.
    /// @returns  call instruction to generated GenISA_GetBufferPtr.
    llvm::CallInst*     genGetBufferPtr(llvm::CallInst &callInst, BufferType bufType);

    /// @brief  Indicates if the pass changed the processed function
    bool m_changed;
};
}