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// adjust.cpp: source file

/********************************************************************

//

// Module:

//   Pipeline Output Adjusting Unit

//

// Implementation:

//   This module performs some of the shifts there are needed to

//   obtain final results.

//

//

// Authors:     Winnie Cheng <wwcheng@stanford.edu>,

//              Peter Wu <peter5@stanford.edu>

//

 *********************************************************************/

#include "adjust.h"

#include "opcode.h"

#ifdef MODULE_NAME

#undef MODULE_NAME

#endif

#define MODULE_NAME     "adjust"

#define DEBUG           1

#if DEBUG

#define dprintf         printf

#else

#define dprintf

#endif

void adjust::adjust_process()

{

    sc_uint<UNIT_SEL_WIDTH> opcode;

    short x, y, acc_phase;

    short result1, result2;

    // On Reset, initialize output

    result_valid.write(true);

    out_opcode.write(I_NOP);

    out_result1.write(0);

    out_result2.write(0);

    wait();

    while(1) {

        wait();

        // propagate through

        opcode = in_opcode.read();

        out_opcode.write(opcode);

        if(in_valid.read()==true){

            // Register input

            x = in_x.read();

            y = in_y.read();

            acc_phase = in_acc_phase.read();

            // Adjust according to opcode

            if(opcode == I_ROTATE) {

                // Rotate Instruction Format

                //   operand1 : orgX

                //   operand2 : orgY

                //   operand3 : angle

                // returns

                //   result1 : rotated x-coordinate

                //   result2 : rotated y-coordinate

                // Reduce vector size by multiplier

                //   (1/2+1/8-1/64-1/512)

                // adjust

                result1=(x>>1)+(x>>3)-(x>>6)-(x>>9);

                result2=(y>>1)+(y>>3)-(y>>6)-(y>>9);

                // output results

                out_result1.write(result1);

                out_result2.write(result2);

                result_valid.write(true);

                dprintf("[%s] Adjust ROTATE\n", MODULE_NAME);

            } else if (opcode == I_MAGPHASE) {

                // Magphase Instruction Format

                //   operand1 : X

                //   operand2 : Y

                // returns

                //   result1 : magnitude

                //   result2 : phase

                // adjust

                result1 = (x>>1)+(x>>3)-(x>>6)-(x>>9);

                result2 = -acc_phase;

                // output results

                out_result1.write(result1);

                out_result2.write(result2);

                result_valid.write(true);

                dprintf("[%s] Adjust MAG-PHASE\n", MODULE_NAME);

            } else if (opcode == I_SINCOS || opcode == I_SINHCOSH) {

                // SinCos/SinhCosh Instruction Format

                //   operand1 : phase

                // return

                //   result1 : sin/sinh(phase)

                //   result2 : cos/cosh(phase)

                // no adjustment needed

                // output results

                out_result1.write(y);   // sin/sinh result

                out_result2.write(x);   // cos/cosh result

                result_valid.write(true);

                dprintf("[%s] Adjust SINCOS or SINHCOSH\n", MODULE_NAME);

            } else {

                // filter out NOP results

                result_valid.write(false);

                dprintf("[%s] Adjust ignored NOP\n", MODULE_NAME);

            }

        } else {

            result_valid.write(false);

            dprintf("[%s] Nothing to adjust\n", MODULE_NAME);

        }

    } // forever loop   

}