Scale2xScaler.cpp

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/*
 * This file is part of the Scale2x project.
 *
 * Copyright (C) 2001, 2002, 2003, 2004 Andrea Mazzoleni
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

/*
 * This file contains a C and MMX implementation of the Scale2x effect.
 *
 * You can find an high level description of the effect at :
 *
 * http://scale2x.sourceforge.net/
 *
 * Alternatively at the previous license terms, you are allowed to use this
 * code in your program with these conditions:
 * - the program is not used in commercial activities.
 * - the whole source code of the program is released with the binary.
 * - derivative works of the program are allowed.
 */

#include "pent_include.h"
#include "Scale2xScaler.h"
#include "Manips.h"

// SDL_cpuinfo.h needs SDL_types.h, but fails to include it
#include <SDL_types.h>
#include <SDL_cpuinfo.h>

namespace Pentagram {

/***************************************************************************/
/* Scale2x C implementation */

template<class uintX, class Manip, class uintS=uintX> class Scale2xScalerInternal
{
public:

static inline void scale2x_def(uintX* dst0, uintX* dst1, const uintS* src0, const uintS* src1, const uintS* src2, unsigned count)
{
        /* first pixel */
        if (src0[0] != src2[0] && src1[0] != src1[1]) {
                dst0[0] = Manip::copy(src1[0] == src0[0] ? src0[0] : src1[0]);
                dst0[1] = Manip::copy(src1[1] == src0[0] ? src0[0] : src1[0]);
                dst1[0] = Manip::copy(src1[0] == src2[0] ? src2[0] : src1[0]);
                dst1[1] = Manip::copy(src1[1] == src2[0] ? src2[0] : src1[0]);
        } else {
                dst0[0] = Manip::copy(src1[0]);
                dst0[1] = Manip::copy(src1[0]);
                dst1[0] = Manip::copy(src1[0]);
                dst1[1] = Manip::copy(src1[0]);
        }
        ++src0;
        ++src1;
        ++src2;
        dst0 += 2;
        dst1 += 2;

        /* central pixels */
        count -= 2;
        while (count) {
                if (src0[0] != src2[0] && src1[-1] != src1[1]) {
                        dst0[0] = Manip::copy(src1[-1] == src0[0] ? src0[0] : src1[0]);
                        dst0[1] = Manip::copy(src1[1] == src0[0] ? src0[0] : src1[0]);
                        dst1[0] = Manip::copy(src1[-1] == src2[0] ? src2[0] : src1[0]);
                        dst1[1] = Manip::copy(src1[1] == src2[0] ? src2[0] : src1[0]);
                } else {
                        dst0[0] = Manip::copy(src1[0]);
                        dst0[1] = Manip::copy(src1[0]);
                        dst1[0] = Manip::copy(src1[0]);
                        dst1[1] = Manip::copy(src1[0]);
                }

                ++src0;
                ++src1;
                ++src2;
                dst0 += 2;
                dst1 += 2;
                --count;
        }

        /* last pixel */
        if (src0[0] != src2[0] && src1[-1] != src1[0]) {
                dst0[0] = Manip::copy(src1[-1] == src0[0] ? src0[0] : src1[0]);
                dst0[1] = Manip::copy(src1[0] == src0[0] ? src0[0] : src1[0]);
                dst1[0] = Manip::copy(src1[-1] == src2[0] ? src2[0] : src1[0]);
                dst1[1] = Manip::copy(src1[0] == src2[0] ? src2[0] : src1[0]);
        } else {
                dst0[0] = Manip::copy(src1[0]);
                dst0[1] = Manip::copy(src1[0]);
                dst1[0] = Manip::copy(src1[0]);
                dst1[1] = Manip::copy(src1[0]);
        }
}


static bool Scale( Texture *tex, sint32 sx, sint32 sy, sint32 sw, sint32 sh, 
                                        uint8* pixel, sint32 dw, sint32 dh, sint32 pitch, bool clamp_src)
{
        // Must be at least 3 high
        if (sh<3 && (clamp_src || tex->height<3)) return false;

        // Source buffer pointers
        uintS *texel = reinterpret_cast<uintS*>(tex->buffer) + (sy * tex->width + sx);
        int tpitch = tex->width;
//      uintS *tline_end = texel + sw;
        uintS *tex_end = texel + (sh-1)*tex->width;

        bool clip_y = true;
        if (sh+sy < tex->height && clamp_src == false)
        {
                clip_y = false;
                tex_end = texel + sh*tex->width;
        }

        if (sy == 0) {
                scale2x_def(reinterpret_cast<uintX*>(pixel), 
                                        reinterpret_cast<uintX*>(pixel+pitch), 
                                        texel, texel, texel+tpitch, sw);
                pixel += pitch*2;
                texel += tpitch;
        }

        // Src Loop Y
        if (texel != tex_end) do {

                scale2x_def(reinterpret_cast<uintX*>(pixel), 
                                        reinterpret_cast<uintX*>(pixel+pitch), 
                                        texel-tpitch, texel, texel+tpitch, sw);
                pixel += pitch*2;
                texel += tpitch;

        } while (texel != tex_end);

        if (clip_y) {
                scale2x_def(reinterpret_cast<uintX*>(pixel), 
                                        reinterpret_cast<uintX*>(pixel+pitch), 
                                        texel-tpitch, texel, texel, sw);
        }

        return true;
}

};

/***************************************************************************/
/* Scale2x MMX implementation */

#if (defined(__GNUC__) && defined(__i386__)) || (defined(_MSC_VER) && defined(_M_IX86))

#ifdef _MSC_VER
#pragma warning(disable:4799)   // No EMMS at end of function
#endif

/*
 * Apply the Scale2x effect at a single row.
 * This function must be called only by the other scale2x functions.
 *
 * Considering the pixel map :
 *
 *      ABC (src0)
 *      DEF (src1)
 *      GHI (src2)
 *
 * this functions compute 2 new pixels in substitution of the source pixel E
 * like this map :
 *
 *      ab (dst)
 *
 * with these variables :
 *
 *      &current -> E
 *      &current_left -> D
 *      &current_right -> F
 *      &current_upper -> B
 *      &current_lower -> H
 *
 *      %0 -> current_upper
 *      %1 -> current
 *      %2 -> current_lower
 *      %3 -> dst
 *      %4 -> counter
 *
 *      %mm0 -> *current_left
 *      %mm1 -> *current_next
 *      %mm2 -> tmp0
 *      %mm3 -> tmp1
 *      %mm4 -> tmp2
 *      %mm5 -> tmp3
 *      %mm6 -> *current_upper
 *      %mm7 -> *current
 */
static inline void scale2x_16_mmx_border(uint16* dst, const uint16* src0, const uint16* src1, const uint16* src2, unsigned count)
{
        /* always do the first and last run */
        count -= 2*4;

#if defined(__GNUC__) && defined(__i386__)
        __asm__ __volatile__(
/* first run */
                /* set the current, current_pre, current_next registers */
                "movq 0(%1), %%mm0\n"
                "movq 0(%1), %%mm7\n"
                "movq 8(%1), %%mm1\n"
                "psllq $48, %%mm0\n"
                "psllq $48, %%mm1\n"
                "psrlq $48, %%mm0\n"
                "movq %%mm7, %%mm2\n"
                "movq %%mm7, %%mm3\n"
                "psllq $16, %%mm2\n"
                "psrlq $16, %%mm3\n"
                "por %%mm2, %%mm0\n"
                "por %%mm3, %%mm1\n"

                /* current_upper */
                "movq (%0), %%mm6\n"

                /* compute the upper-left pixel for dst on %%mm2 */
                /* compute the upper-right pixel for dst on %%mm4 */
                "movq %%mm0, %%mm2\n"
                "movq %%mm1, %%mm4\n"
                "movq %%mm0, %%mm3\n"
                "movq %%mm1, %%mm5\n"
                "pcmpeqw %%mm6, %%mm2\n"
                "pcmpeqw %%mm6, %%mm4\n"
                "pcmpeqw (%2), %%mm3\n"
                "pcmpeqw (%2), %%mm5\n"
                "pandn %%mm2, %%mm3\n"
                "pandn %%mm4, %%mm5\n"
                "movq %%mm0, %%mm2\n"
                "movq %%mm1, %%mm4\n"
                "pcmpeqw %%mm1, %%mm2\n"
                "pcmpeqw %%mm0, %%mm4\n"
                "pandn %%mm3, %%mm2\n"
                "pandn %%mm5, %%mm4\n"
                "movq %%mm2, %%mm3\n"
                "movq %%mm4, %%mm5\n"
                "pand %%mm6, %%mm2\n"
                "pand %%mm6, %%mm4\n"
                "pandn %%mm7, %%mm3\n"
                "pandn %%mm7, %%mm5\n"
                "por %%mm3, %%mm2\n"
                "por %%mm5, %%mm4\n"

                /* set *dst */
                "movq %%mm2, %%mm3\n"
                "punpcklwd %%mm4, %%mm2\n"
                "punpckhwd %%mm4, %%mm3\n"
                "movq %%mm2, (%3)\n"
                "movq %%mm3, 8(%3)\n"

                /* next */
                "addl $8, %0\n"
                "addl $8, %1\n"
                "addl $8, %2\n"
                "addl $16, %3\n"

/* central runs */
                "shrl $2, %4\n"
                "jz 1f\n"

                "0:\n"

                /* set the current, current_pre, current_next registers */
                "movq -8(%1), %%mm0\n"
                "movq (%1), %%mm7\n"
                "movq 8(%1), %%mm1\n"
                "psrlq $48, %%mm0\n"
                "psllq $48, %%mm1\n"
                "movq %%mm7, %%mm2\n"
                "movq %%mm7, %%mm3\n"
                "psllq $16, %%mm2\n"
                "psrlq $16, %%mm3\n"
                "por %%mm2, %%mm0\n"
                "por %%mm3, %%mm1\n"

                /* current_upper */
                "movq (%0), %%mm6\n"

                /* compute the upper-left pixel for dst on %%mm2 */
                /* compute the upper-right pixel for dst on %%mm4 */
                "movq %%mm0, %%mm2\n"
                "movq %%mm1, %%mm4\n"
                "movq %%mm0, %%mm3\n"
                "movq %%mm1, %%mm5\n"
                "pcmpeqw %%mm6, %%mm2\n"
                "pcmpeqw %%mm6, %%mm4\n"
                "pcmpeqw (%2), %%mm3\n"
                "pcmpeqw (%2), %%mm5\n"
                "pandn %%mm2, %%mm3\n"
                "pandn %%mm4, %%mm5\n"
                "movq %%mm0, %%mm2\n"
                "movq %%mm1, %%mm4\n"
                "pcmpeqw %%mm1, %%mm2\n"
                "pcmpeqw %%mm0, %%mm4\n"
                "pandn %%mm3, %%mm2\n"
                "pandn %%mm5, %%mm4\n"
                "movq %%mm2, %%mm3\n"
                "movq %%mm4, %%mm5\n"
                "pand %%mm6, %%mm2\n"
                "pand %%mm6, %%mm4\n"
                "pandn %%mm7, %%mm3\n"
                "pandn %%mm7, %%mm5\n"
                "por %%mm3, %%mm2\n"
                "por %%mm5, %%mm4\n"

                /* set *dst */
                "movq %%mm2, %%mm3\n"
                "punpcklwd %%mm4, %%mm2\n"
                "punpckhwd %%mm4, %%mm3\n"
                "movq %%mm2, (%3)\n"
                "movq %%mm3, 8(%3)\n"

                /* next */
                "addl $8, %0\n"
                "addl $8, %1\n"
                "addl $8, %2\n"
                "addl $16, %3\n"

                "decl %4\n"
                "jnz 0b\n"
                "1:\n"

/* final run */
                /* set the current, current_pre, current_next registers */
                "movq (%1), %%mm1\n"
                "movq (%1), %%mm7\n"
                "movq -8(%1), %%mm0\n"
                "psrlq $48, %%mm1\n"
                "psrlq $48, %%mm0\n"
                "psllq $48, %%mm1\n"
                "movq %%mm7, %%mm2\n"
                "movq %%mm7, %%mm3\n"
                "psllq $16, %%mm2\n"
                "psrlq $16, %%mm3\n"
                "por %%mm2, %%mm0\n"
                "por %%mm3, %%mm1\n"

                /* current_upper */
                "movq (%0), %%mm6\n"

                /* compute the upper-left pixel for dst on %%mm2 */
                /* compute the upper-right pixel for dst on %%mm4 */
                "movq %%mm0, %%mm2\n"
                "movq %%mm1, %%mm4\n"
                "movq %%mm0, %%mm3\n"
                "movq %%mm1, %%mm5\n"
                "pcmpeqw %%mm6, %%mm2\n"
                "pcmpeqw %%mm6, %%mm4\n"
                "pcmpeqw (%2), %%mm3\n"
                "pcmpeqw (%2), %%mm5\n"
                "pandn %%mm2, %%mm3\n"
                "pandn %%mm4, %%mm5\n"
                "movq %%mm0, %%mm2\n"
                "movq %%mm1, %%mm4\n"
                "pcmpeqw %%mm1, %%mm2\n"
                "pcmpeqw %%mm0, %%mm4\n"
                "pandn %%mm3, %%mm2\n"
                "pandn %%mm5, %%mm4\n"
                "movq %%mm2, %%mm3\n"
                "movq %%mm4, %%mm5\n"
                "pand %%mm6, %%mm2\n"
                "pand %%mm6, %%mm4\n"
                "pandn %%mm7, %%mm3\n"
                "pandn %%mm7, %%mm5\n"
                "por %%mm3, %%mm2\n"
                "por %%mm5, %%mm4\n"

                /* set *dst */
                "movq %%mm2, %%mm3\n"
                "punpcklwd %%mm4, %%mm2\n"
                "punpckhwd %%mm4, %%mm3\n"
                "movq %%mm2, (%3)\n"
                "movq %%mm3, 8(%3)\n"

                : "+r" (src0), "+r" (src1), "+r" (src2), "+r" (dst), "+r" (count)
                :
                : "cc"
        );
#elif defined(_MSC_VER) && defined(_M_IX86)
        __asm {
                mov eax, src0;
                mov ebx, src1;
            mov ecx, src2;
                mov edx, dst;
                mov esi, count;

/* first run */
                /* set the current, current_pre, current_next registers */
                movq mm0, [ebx+0];
                movq mm7, [ebx+0];
                movq mm1, [ebx+8];
                psllq mm0, 48;
                psllq mm1, 48;
                psrlq mm0, 48;
                movq mm2, mm7;
                movq mm3, mm7;
                psllq mm2, 16;
                psrlq mm3, 16;
                por mm0, mm2;
                por mm1, mm3;

                /* current_upper */
                movq mm6, [eax];

                /* compute the upper-left pixel for dst on mm2 */
                /* compute the upper-right pixel for dst on mm4 */
                movq mm2, mm0;
                movq mm4, mm1;
                movq mm3, mm0;
                movq mm5, mm1;
                pcmpeqw mm2, mm6;
                pcmpeqw mm4, mm6;
                pcmpeqw mm3, [ecx];
                pcmpeqw mm5, [ecx];
                pandn mm3, mm2;
                pandn mm5, mm4;
                movq mm2, mm0;
                movq mm4, mm1;
                pcmpeqw mm2, mm1;
                pcmpeqw mm4, mm0;
                pandn mm2, mm3;
                pandn mm4, mm5;
                movq mm3, mm2;
                movq mm5, mm4;
                pand mm2, mm6;
                pand mm4, mm6;
                pandn mm3, mm7;
                pandn mm5, mm7;
                por mm2, mm3;
                por mm4, mm5;

                /* set *dst */
                movq mm3, mm2;
                punpcklwd mm2, mm4;
                punpckhwd mm3, mm4;
                movq [edx], mm2;
                movq [edx+8], mm3;

                /* next */
                add eax, 8;
                add ebx, 8;
                add ecx, 8;
                add edx, 16;

/* central runs */
                shr esi, 2;
                jz label1;
            align 4;
label0:

                /* set the current, current_pre, current_next registers */
                movq mm0, [ebx-8];
                movq mm7, [ebx];
                movq mm1, [ebx+8];
                psrlq mm0, 48;
                psllq mm1, 48;
                movq mm2, mm7;
                movq mm3, mm7;
                psllq mm2, 16;
                psrlq mm3, 16;
                por mm0, mm2;
                por mm1, mm3;

                /* current_upper */
                movq mm6, [eax];

                /* compute the upper-left pixel for dst on mm2 */
                /* compute the upper-right pixel for dst on mm4 */
                movq mm2, mm0;
                movq mm4, mm1;
                movq mm3, mm0;
                movq mm5, mm1;
                pcmpeqw mm2, mm6;
                pcmpeqw mm4, mm6;
                pcmpeqw mm3, [ecx];
                pcmpeqw mm5, [ecx];
                pandn mm3, mm2;
                pandn mm5, mm4;
                movq mm2, mm0;
                movq mm4, mm1;
                pcmpeqw mm2, mm1;
                pcmpeqw mm4, mm0;
                pandn mm2, mm3;
                pandn mm4, mm5;
                movq mm3, mm2;
                movq mm5, mm4;
                pand mm2, mm6;
                pand mm4, mm6;
                pandn mm3, mm7;
                pandn mm5, mm7;
                por mm2, mm3;
                por mm4, mm5;

                /* set *dst */
                movq mm3, mm2;
                punpcklwd mm2, mm4;
                punpckhwd mm3, mm4;
                movq [edx], mm2;
                movq [edx+8], mm3;

                /* next */
                add eax, 8;
                add ebx, 8;
                add ecx, 8;
                add edx, 16;

                dec esi;
                jnz label0;
label1:

/* final run */
                /* set the current, current_pre, current_next registers */
                movq mm1, [ebx];
                movq mm7, [ebx];
                movq mm0, [ebx-8];
                psrlq mm1, 48;
                psrlq mm0, 48;
                psllq mm1, 48;
                movq mm2, mm7;
                movq mm3, mm7;
                psllq mm2, 16;
                psrlq mm3, 16;
                por mm0, mm2;
                por mm1, mm3;

                /* current_upper */
                movq mm6, [eax];

                /* compute the upper-left pixel for dst on mm2 */
                /* compute the upper-right pixel for dst on mm4 */
                movq mm2, mm0;
                movq mm4, mm1;
                movq mm3, mm0;
                movq mm5, mm1;
                pcmpeqw mm2, mm6;
                pcmpeqw mm4, mm6;
                pcmpeqw mm3, [ecx];
                pcmpeqw mm5, [ecx];
                pandn mm3, mm2;
                pandn mm5, mm4;
                movq mm2, mm0;
                movq mm4, mm1;
                pcmpeqw mm2, mm1;
                pcmpeqw mm4, mm0;
                pandn mm2, mm3;
                pandn mm4, mm5;
                movq mm3, mm2;
                movq mm5, mm4;
                pand mm2, mm6;
                pand mm4, mm6;
                pandn mm3, mm7;
                pandn mm5, mm7;
                por mm2, mm3;
                por mm4, mm5;

                /* set *dst */
                movq mm3, mm2;
                punpcklwd mm2, mm4;
                punpckhwd mm3, mm4;
                movq [edx], mm2;
                movq [edx+8], mm3;
        }
#endif
}

static inline void scale2x_32_mmx_border(uint32* dst, const uint32* src0, const uint32* src1, const uint32* src2, unsigned count)
{
        /* always do the first and last run */
        count -= 2*2;

#if defined(__GNUC__) && defined(__i386__)
        __asm__ __volatile__(
/* first run */
                /* set the current, current_pre, current_next registers */
                "movq 0(%1), %%mm0\n"
                "movq 0(%1), %%mm7\n"
                "movq 8(%1), %%mm1\n"
                "psllq $32, %%mm0\n"
                "psllq $32, %%mm1\n"
                "psrlq $32, %%mm0\n"
                "movq %%mm7, %%mm2\n"
                "movq %%mm7, %%mm3\n"
                "psllq $32, %%mm2\n"
                "psrlq $32, %%mm3\n"
                "por %%mm2, %%mm0\n"
                "por %%mm3, %%mm1\n"

                /* current_upper */
                "movq (%0), %%mm6\n"

                /* compute the upper-left pixel for dst on %%mm2 */
                /* compute the upper-right pixel for dst on %%mm4 */
                "movq %%mm0, %%mm2\n"
                "movq %%mm1, %%mm4\n"
                "movq %%mm0, %%mm3\n"
                "movq %%mm1, %%mm5\n"
                "pcmpeqd %%mm6, %%mm2\n"
                "pcmpeqd %%mm6, %%mm4\n"
                "pcmpeqd (%2), %%mm3\n"
                "pcmpeqd (%2), %%mm5\n"
                "pandn %%mm2, %%mm3\n"
                "pandn %%mm4, %%mm5\n"
                "movq %%mm0, %%mm2\n"
                "movq %%mm1, %%mm4\n"
                "pcmpeqd %%mm1, %%mm2\n"
                "pcmpeqd %%mm0, %%mm4\n"
                "pandn %%mm3, %%mm2\n"
                "pandn %%mm5, %%mm4\n"
                "movq %%mm2, %%mm3\n"
                "movq %%mm4, %%mm5\n"
                "pand %%mm6, %%mm2\n"
                "pand %%mm6, %%mm4\n"
                "pandn %%mm7, %%mm3\n"
                "pandn %%mm7, %%mm5\n"
                "por %%mm3, %%mm2\n"
                "por %%mm5, %%mm4\n"

                /* set *dst */
                "movq %%mm2, %%mm3\n"
                "punpckldq %%mm4, %%mm2\n"
                "punpckhdq %%mm4, %%mm3\n"
                "movq %%mm2, (%3)\n"
                "movq %%mm3, 8(%3)\n"

                /* next */
                "addl $8, %0\n"
                "addl $8, %1\n"
                "addl $8, %2\n"
                "addl $16, %3\n"

/* central runs */
                "shrl $1, %4\n"
                "jz 1f\n"

                "0:\n"

                /* set the current, current_pre, current_next registers */
                "movq -8(%1), %%mm0\n"
                "movq (%1), %%mm7\n"
                "movq 8(%1), %%mm1\n"
                "psrlq $32, %%mm0\n"
                "psllq $32, %%mm1\n"
                "movq %%mm7, %%mm2\n"
                "movq %%mm7, %%mm3\n"
                "psllq $32, %%mm2\n"
                "psrlq $32, %%mm3\n"
                "por %%mm2, %%mm0\n"
                "por %%mm3, %%mm1\n"

                /* current_upper */
                "movq (%0), %%mm6\n"

                /* compute the upper-left pixel for dst on %%mm2 */
                /* compute the upper-right pixel for dst on %%mm4 */
                "movq %%mm0, %%mm2\n"
                "movq %%mm1, %%mm4\n"
                "movq %%mm0, %%mm3\n"
                "movq %%mm1, %%mm5\n"
                "pcmpeqd %%mm6, %%mm2\n"
                "pcmpeqd %%mm6, %%mm4\n"
                "pcmpeqd (%2), %%mm3\n"
                "pcmpeqd (%2), %%mm5\n"
                "pandn %%mm2, %%mm3\n"
                "pandn %%mm4, %%mm5\n"
                "movq %%mm0, %%mm2\n"
                "movq %%mm1, %%mm4\n"
                "pcmpeqd %%mm1, %%mm2\n"
                "pcmpeqd %%mm0, %%mm4\n"
                "pandn %%mm3, %%mm2\n"
                "pandn %%mm5, %%mm4\n"
                "movq %%mm2, %%mm3\n"
                "movq %%mm4, %%mm5\n"
                "pand %%mm6, %%mm2\n"
                "pand %%mm6, %%mm4\n"
                "pandn %%mm7, %%mm3\n"
                "pandn %%mm7, %%mm5\n"
                "por %%mm3, %%mm2\n"
                "por %%mm5, %%mm4\n"

                /* set *dst */
                "movq %%mm2, %%mm3\n"
                "punpckldq %%mm4, %%mm2\n"
                "punpckhdq %%mm4, %%mm3\n"
                "movq %%mm2, (%3)\n"
                "movq %%mm3, 8(%3)\n"

                /* next */
                "addl $8, %0\n"
                "addl $8, %1\n"
                "addl $8, %2\n"
                "addl $16, %3\n"

                "decl %4\n"
                "jnz 0b\n"
                "1:\n"

/* final run */
                /* set the current, current_pre, current_next registers */
                "movq (%1), %%mm1\n"
                "movq (%1), %%mm7\n"
                "movq -8(%1), %%mm0\n"
                "psrlq $32, %%mm1\n"
                "psrlq $32, %%mm0\n"
                "psllq $32, %%mm1\n"
                "movq %%mm7, %%mm2\n"
                "movq %%mm7, %%mm3\n"
                "psllq $32, %%mm2\n"
                "psrlq $32, %%mm3\n"
                "por %%mm2, %%mm0\n"
                "por %%mm3, %%mm1\n"

                /* current_upper */
                "movq (%0), %%mm6\n"

                /* compute the upper-left pixel for dst on %%mm2 */
                /* compute the upper-right pixel for dst on %%mm4 */
                "movq %%mm0, %%mm2\n"
                "movq %%mm1, %%mm4\n"
                "movq %%mm0, %%mm3\n"
                "movq %%mm1, %%mm5\n"
                "pcmpeqd %%mm6, %%mm2\n"
                "pcmpeqd %%mm6, %%mm4\n"
                "pcmpeqd (%2), %%mm3\n"
                "pcmpeqd (%2), %%mm5\n"
                "pandn %%mm2, %%mm3\n"
                "pandn %%mm4, %%mm5\n"
                "movq %%mm0, %%mm2\n"
                "movq %%mm1, %%mm4\n"
                "pcmpeqd %%mm1, %%mm2\n"
                "pcmpeqd %%mm0, %%mm4\n"
                "pandn %%mm3, %%mm2\n"
                "pandn %%mm5, %%mm4\n"
                "movq %%mm2, %%mm3\n"
                "movq %%mm4, %%mm5\n"
                "pand %%mm6, %%mm2\n"
                "pand %%mm6, %%mm4\n"
                "pandn %%mm7, %%mm3\n"
                "pandn %%mm7, %%mm5\n"
                "por %%mm3, %%mm2\n"
                "por %%mm5, %%mm4\n"

                /* set *dst */
                "movq %%mm2, %%mm3\n"
                "punpckldq %%mm4, %%mm2\n"
                "punpckhdq %%mm4, %%mm3\n"
                "movq %%mm2, (%3)\n"
                "movq %%mm3, 8(%3)\n"

                : "+r" (src0), "+r" (src1), "+r" (src2), "+r" (dst), "+r" (count)
                :
                : "cc"
        );
#elif defined(_MSC_VER) && defined(_M_IX86)
        __asm {
                mov eax, src0;
                mov ebx, src1;
            mov ecx, src2;
                mov edx, dst;
                mov esi, count;

/* first run */
                /* set the current, current_pre, current_next registers */
                movq mm0, [ebx+0];
                movq mm7, [ebx+0];
                movq mm1, [ebx+8];
                psllq mm0, 32;
                psllq mm1, 32;
                psrlq mm0, 32;
                movq mm2, mm7;
                movq mm3, mm7;
                psllq mm2, 32;
                psrlq mm3, 32;
                por mm0, mm2;
                por mm1, mm3;

                /* current_upper */
                movq mm6, [eax];

                /* compute the upper-left pixel for dst on mm2 */
                /* compute the upper-right pixel for dst on mm4 */
                movq mm2, mm0;
                movq mm4, mm1;
                movq mm3, mm0;
                movq mm5, mm1;
                pcmpeqd mm2, mm6;
                pcmpeqd mm4, mm6;
                pcmpeqd mm3, [ecx];
                pcmpeqd mm5, [ecx];
                pandn mm3, mm2;
                pandn mm5, mm4;
                movq mm2, mm0;
                movq mm4, mm1;
                pcmpeqd mm2, mm1;
                pcmpeqd mm4, mm0;
                pandn mm2, mm3;
                pandn mm4, mm5;
                movq mm3, mm2;
                movq mm5, mm4;
                pand mm2, mm6;
                pand mm4, mm6;
                pandn mm3, mm7;
                pandn mm5, mm7;
                por mm2, mm3;
                por mm4, mm5;

                /* set *dst */
                movq mm3, mm2;
                punpckldq mm2, mm4;
                punpckhdq mm3, mm4;
                movq [edx], mm2;
                movq [edx+8], mm3;

                /* next */
                add eax, 8;
                add ebx, 8;
                add ecx, 8;
                add edx, 16;

/* central runs */
                shr esi, 1;
                jz label1;

label0:

                /* set the current, current_pre, current_next registers */
                movq mm0, [ebx-8];
                movq mm7, [ebx];
                movq mm1, [ebx+8];
                psrlq mm0, 32;
                psllq mm1, 32;
                movq mm2, mm7;
                movq mm3, mm7;
                psllq mm2, 32;
                psrlq mm3, 32;
                por mm0, mm2;
                por mm1, mm3;

                /* current_upper */
                movq mm6, [eax];

                /* compute the upper-left pixel for dst on mm2 */
                /* compute the upper-right pixel for dst on mm4 */
                movq mm2, mm0;
                movq mm4, mm1;
                movq mm3, mm0;
                movq mm5, mm1;
                pcmpeqd mm2, mm6;
                pcmpeqd mm4, mm6;
                pcmpeqd mm3, [ecx];
                pcmpeqd mm5, [ecx];
                pandn mm3, mm2;
                pandn mm5, mm4;
                movq mm2, mm0;
                movq mm4, mm1;
                pcmpeqd mm2, mm1;
                pcmpeqd mm4, mm0;
                pandn mm2, mm3;
                pandn mm4, mm5;
                movq mm3, mm2;
                movq mm5, mm4;
                pand mm2, mm6;
                pand mm4, mm6;
                pandn mm3, mm7;
                pandn mm5, mm7;
                por mm2, mm3;
                por mm4, mm5;

                /* set *dst */
                movq mm3, mm2;
                punpckldq mm2, mm4;
                punpckhdq mm3, mm4;
                movq [edx], mm2;
                movq [edx+8], mm3;

                /* next */
                add eax, 8;
                add ebx, 8;
                add ecx, 8;
                add edx, 16;

                dec esi;
                jnz label0
label1:

/* final run */
                /* set the current, current_pre, current_next registers */
                movq mm1, [ebx];
                movq mm7, [ebx];
                movq mm0, [ebx-8];
                psrlq mm1, 32;
                psrlq mm0, 32;
                psllq mm1, 32;
                movq mm2, mm7;
                movq mm3, mm7;
                psllq mm2, 32;
                psrlq mm3, 32;
                por mm0, mm2;
                por mm1, mm3;

                /* current_upper */
                movq mm6, [eax];

                /* compute the upper-left pixel for dst on mm2 */
                /* compute the upper-right pixel for dst on mm4 */
                movq mm2, mm0;
                movq mm4, mm1;
                movq mm3, mm0;
                movq mm5, mm1;
                pcmpeqd mm2, mm6;
                pcmpeqd mm4, mm6;
                pcmpeqd mm3, [ecx];
                pcmpeqd mm5, [ecx];
                pandn mm3, mm2;
                pandn mm5, mm4;
                movq mm2, mm0;
                movq mm4, mm1;
                pcmpeqd mm2, mm1;
                pcmpeqd mm4, mm0;
                pandn mm2, mm3;
                pandn mm4, mm5;
                movq mm3, mm2;
                movq mm5, mm4;
                pand mm2, mm6;
                pand mm4, mm6;
                pandn mm3, mm7;
                pandn mm5, mm7;
                por mm2, mm3;
                por mm4, mm5;

                /* set *dst */
                movq mm3, mm2;
                punpckldq mm2, mm4;
                punpckhdq mm3, mm4;
                movq [edx], mm2;
                movq [edx+8], mm3;
        };
#endif
}

static inline void scale2x_mmx_emms(void)
{
#if defined(__GNUC__) && defined(__i386__)
        __asm__ __volatile__ (
                "emms"
        );
#elif defined(_MSC_VER) && defined(_M_IX86)
        __asm emms;
#endif
}

static void scale2x_16_mmx(uint16* dst0, uint16* dst1, const uint16* src0, const uint16* src1, const uint16* src2, unsigned count)
{
        if (count % 4 != 0 || count < 8) {
                Scale2xScalerInternal<uint16, Manip_Nat2Nat_16>::scale2x_def(dst0, dst1, src0, src1, src2, count);
        } else {
                scale2x_16_mmx_border(dst0, src0, src1, src2, count);
                scale2x_16_mmx_border(dst1, src2, src1, src0, count);
        }
}

static void scale2x_32_mmx(uint32* dst0, uint32* dst1, const uint32* src0, const uint32* src1, const uint32* src2, unsigned count)
{
        if (count % 2 != 0 || count < 4) {
                Scale2xScalerInternal<uint32, Manip_Nat2Nat_32>::scale2x_def(dst0, dst1, src0, src1, src2, count);
        } else {
                scale2x_32_mmx_border(dst0, src0, src1, src2, count);
                scale2x_32_mmx_border(dst1, src2, src1, src0, count);
        }
}

//
// Pentagram Scale2x Implementation
//

static bool Scale2x_16MMX( Texture *tex , sint32 sx, sint32 sy, sint32 sw, sint32 sh, 
                                        uint8* pixel, sint32 dw, sint32 dh, sint32 pitch, bool clamp_src)
{
        // Must be at least 3 high
        if (sh<3 && (clamp_src || tex->height<3)) return false;

        // Source buffer pointers
        uint16 *texel = reinterpret_cast<uint16*>(tex->buffer) + (sy * tex->width + sx);
        int tpitch = tex->width;
//      uint16 *tline_end = texel + sw;
        uint16 *tex_end = texel + (sh-1)*tex->width;

        bool clip_y = true;
        if (sh+sy < tex->height && clamp_src == false)
        {
                clip_y = false;
                tex_end = texel + sh*tex->width;
        }

        if (sy == 0) {
                scale2x_16_mmx(reinterpret_cast<uint16*>(pixel), 
                                        reinterpret_cast<uint16*>(pixel+pitch), 
                                        texel, texel, texel+tpitch, sw);
                pixel += pitch*2;
                texel += tpitch;
        }

        // Src Loop Y
        if (texel != tex_end) do {

                scale2x_16_mmx(reinterpret_cast<uint16*>(pixel), 
                                        reinterpret_cast<uint16*>(pixel+pitch), 
                                        texel-tpitch, texel, texel+tpitch, sw);
                pixel += pitch*2;
                texel += tpitch;

        } while (texel != tex_end);

        if (clip_y) {
                scale2x_16_mmx(reinterpret_cast<uint16*>(pixel), 
                                        reinterpret_cast<uint16*>(pixel+pitch), 
                                        texel-tpitch, texel, texel, sw);
        }

        scale2x_mmx_emms();
        return true;
}

static bool Scale2x_32MMX( Texture *tex , sint32 sx, sint32 sy, sint32 sw, sint32 sh, 
                                        uint8* pixel, sint32 dw, sint32 dh, sint32 pitch, bool clamp_src)
{
        // Must be at least 3 high
        if (sh<3 && (clamp_src || tex->height<3)) return false;

        // Source buffer pointers
        uint32 *texel = reinterpret_cast<uint32*>(tex->buffer) + (sy * tex->width + sx);
        int tpitch = tex->width;
//      uint32 *tline_end = texel + sw;
        uint32 *tex_end = texel + (sh-1)*tex->width;

        bool clip_y = true;
        if (sh+sy < tex->height && clamp_src == false)
        {
                clip_y = false;
                tex_end = texel + sh*tex->width;
        }

        if (sy == 0) {
                scale2x_32_mmx(reinterpret_cast<uint32*>(pixel), 
                                        reinterpret_cast<uint32*>(pixel+pitch), 
                                        texel, texel, texel+tpitch, sw);
                pixel += pitch*2;
                texel += tpitch;
        }

        // Src Loop Y
        if (texel != tex_end) do {

                scale2x_32_mmx(reinterpret_cast<uint32*>(pixel), 
                                        reinterpret_cast<uint32*>(pixel+pitch), 
                                        texel-tpitch, texel, texel+tpitch, sw);
                pixel += pitch*2;
                texel += tpitch;

        } while (texel != tex_end);

        if (clip_y) {
                scale2x_32_mmx(reinterpret_cast<uint32*>(pixel), 
                                        reinterpret_cast<uint32*>(pixel+pitch), 
                                        texel-tpitch, texel, texel, sw);
        }

        scale2x_mmx_emms();
        return true;
}
#endif

Scale2xScaler::Scale2xScaler() : Scaler()
{
        Scale16Nat = Scale2xScalerInternal<uint16, Manip_Nat2Nat_16, uint16>::Scale;
        Scale16Sta = Scale2xScalerInternal<uint16, Manip_Sta2Nat_16, uint32>::Scale;

        Scale32Nat = Scale2xScalerInternal<uint32, Manip_Nat2Nat_32, uint32>::Scale;
        Scale32Sta = Scale2xScalerInternal<uint32, Manip_Sta2Nat_32, uint32>::Scale;
        Scale32_A888 = Scale2xScalerInternal<uint32, Manip_Nat2Nat_32, uint32>::Scale;
        Scale32_888A = Scale2xScalerInternal<uint32, Manip_Nat2Nat_32, uint32>::Scale;

#if (defined(__GNUC__) && defined(__i386__)) || (defined(_MSC_VER) && defined(_M_IX86))
        if (SDL_HasMMX()) {
                Scale16Nat = Scale2x_16MMX;

                Scale32Nat = Scale2x_32MMX;
                Scale32_A888 = Scale2x_32MMX;
                Scale32_888A = Scale2x_32MMX;
        }
#endif
}

const uint32 Scale2xScaler::ScaleBits() const { return 1<<2; }
const bool Scale2xScaler::ScaleArbitrary() const { return false; }

const char *Scale2xScaler::ScalerName() const { return "scale2x"; }
const char *Scale2xScaler::ScalerDesc() const { return "AdvMame Scale2x Scaler"; }
const char *Scale2xScaler::ScalerCopyright() const { return "Copyright (C) 2001, 2002, 2003, 2004 Andrea Mazzoleni"; }

const Scale2xScaler scale2x_scaler;

};

---