/*===================== begin_copyright_notice ==================================

Copyright (c) 2017 Intel Corporation

Permission is hereby granted, free of charge, to any person obtaining a
copy of this software and associated documentation files (the
"Software"), to deal in the Software without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Software, and to
permit persons to whom the Software is furnished to do so, subject to
the following conditions:

The above copyright notice and this permission notice shall be included
in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.


======================= end_copyright_notice ==================================*/
#pragma once
#include "Compiler/CISACodeGen/ShaderUnits.hpp"
#include "Compiler/CodeGenPublic.h"
#include "Compiler/CISACodeGen/helper.h"
#include "Compiler/MetaDataUtilsWrapper.h"

#include <llvm/IR/PassManager.h>

namespace IGC
{
class VertexShaderProperties
{
public:
    VertexShaderProperties();
    bool m_HasVertexID;
    unsigned int m_VID;
    bool m_HasInstanceID;
    unsigned int m_IID;
	SVertexFetchSGVExtendedParameters m_VertexFetchSGVExtendedParameters;
    bool m_hasRTAI;
    bool m_hasVPAI;
    bool m_hasClipDistance;
    QuadEltUnit  m_URBOutputLength;
};

class CollectVertexShaderProperties : public llvm::ImmutablePass
{
public:
    CollectVertexShaderProperties();
    static char ID;
    void SetVertexIdSlot(unsigned int VIDslot);
    void SetInstanceIdSlot(unsigned int IIDslot);
	void SetShaderDrawParameter(size_t paramIndex, unsigned int slot);
    void DeclareRTAI();
    void DeclareVPAI();
    void DeclareClipDistance();
    void DeclareOutput(QuadEltUnit newMaxOffset);

    const VertexShaderProperties& GetProperties() { return m_vsProps; }
protected:
    VertexShaderProperties m_vsProps;
};

const unsigned int MaxNumOfOutput = 32;

class VertexShaderLowering : public llvm::FunctionPass
{
public:
    VertexShaderLowering();    
    virtual bool runOnFunction(llvm::Function &F) override;

    virtual void getAnalysisUsage(llvm::AnalysisUsage &AU) const override
    {
        AU.setPreservesCFG();
        AU.addRequired<MetaDataUtilsWrapper>();
        AU.addRequired<CollectVertexShaderProperties>();
        AU.addRequired<CodeGenContextWrapper>();
    }
    static char         ID;
private:

    void LowerIntrinsicInputOutput(llvm::Function &F);
    bool determineIfInstructionUsingInstanceIDisConstantBuffer(
        llvm::Value* user );

    /// Adds a new URB Write instruction to the instruction list
    /// \param offset - indicates the offset in URB at which the write will be performed
    /// \param mask   - 8-bit bitfield indicating which dwords of parameter data should be written
    ///                 0x01 means data[0] only, 0x0F means dwords data[0]..data[3], 
    ///                 0xFF means data[0]..data[7]
    /// \param data   - array of 8 values that are data to be written to URB
    /// \param prev   - new urb write instruction will be added to instruction list before prev.
    void AddURBWrite(llvm::Value* offset, uint mask, llvm::Value* data[8], llvm::Instruction* prev);
    void AddURBRead(llvm::Value* index, llvm::Value* offset, llvm::Instruction* prev);
    unsigned int GetURBOffset(ShaderOutputType type, llvm::Value* attribute, llvm::Instruction* inst);
    void CalculateVertexHeaderSize(llvm::Function& F);
    unsigned int InsertInEmptySlot(llvm::Instruction* sgv, bool bInsertAfterLastUsedSlot = false);
    unsigned int GetUnusedInputSlot();
    unsigned int GetUnusedInputSlotAFterLastUsedOne();
    //HACK: to remove once we don't need header anymore
    void AddInitializedHeader(llvm::Instruction* prev);


private:
    // Maximum number of input vertex elements. Limited by 3DSTATE_VF.
    static const unsigned int MaxNumOfUserInputs = 32; // in 4*DWORD units

    // Maximum number of inputs including SGVs. SGVs can be located in URB past
    // the number of available vertex elements. 
    // Currently additional 2 inputs is enough for all SGVs.
    static const unsigned int MaxNumOfInputs     = 34; // in 4*DWORD units

    CollectVertexShaderProperties* m_vsPropsPass;
    llvm::Module* m_module;
    CodeGenContext* m_context;
    QuadEltUnit m_headerSize;
    bool m_inputUsed[MaxNumOfInputs * 4]; // used vertex elements and SGV slots
    bool m_isHeaderPresent;
};

}//namespace IGC