xref: /xsrc/external/mit/xf86-video-suncg14/dist/src/cg14_render.c

/* $NetBSD: cg14_render.c,v 1.19 2023/01/11 09:23:57 macallan Exp $ */
/*
 * Copyright (c) 2013 Michael Lorenz
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *    - Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *    - Redistributions in binary form must reproduce the above
 *      copyright notice, this list of conditions and the following
 *      disclaimer in the documentation and/or other materials provided
 *      with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <sys/types.h>

/* all driver need this */
#include "xf86.h"
#include "xf86_OSproc.h"
#include "compiler.h"

#include "cg14.h"

/*#define SX_SINGLE*/
/*#define SX_RENDER_DEBUG*/
/*#define SX_RENDER_VERBOSE*/
/*#define SX_ADD_SOFTWARE*/
/*#define SX_RENDER_TRACE*/

#ifdef SX_RENDER_TRACE
#define ENTER xf86Msg(X_ERROR, "%s>\n", __func__);
#define DONE xf86Msg(X_ERROR, "<%s\n", __func__);
#else
#define ENTER
#define DONE
#endif

#ifdef SX_RENDER_DEBUG
#define DPRINTF xf86Msg
#else
#define DPRINTF while (0) xf86Msg
#endif

#ifdef SX_RENDER_VERBOSE
char c[8] = " .,:+*oX";
#endif

void CG14Comp_Over32Solid(Cg14Ptr p,
                   uint32_t src, uint32_t srcpitch,
                   uint32_t dst, uint32_t dstpitch,
                   int width, int height)
{
	uint32_t msk = src, mskx, dstx, m;
	int line, x, i;

	ENTER;

	for (line = 0; line < height; line++) {
		mskx = msk;
		dstx = dst;
#ifndef SX_SINGLE
		int rest;
		for (x = 0; x < width; x += 4) {
			rest = width - x;
			/* fetch 4 mask values */
			sxm(SX_LDUQ0, mskx, 12, 3);
			/* fetch destination pixels */
			sxm(SX_LDUQ0, dstx, 60, 3);
			/* duplicate them for all channels */
			sxi(SX_ORS, 0, 12, 13, 2);
			sxi(SX_ORS, 0, 16, 17, 2);
			sxi(SX_ORS, 0, 20, 21, 2);
			sxi(SX_ORS, 0, 24, 25, 2);
			/* generate inverted alpha */
			sxi(SX_XORS, 12, 8, 28, 15);
			/* multiply source */
			sxi(SX_MUL16X16SR8, 8, 12, 44, 3);
			sxi(SX_MUL16X16SR8, 8, 16, 48, 3);
			sxi(SX_MUL16X16SR8, 8, 20, 52, 3);
			sxi(SX_MUL16X16SR8, 8, 24, 56, 3);
			/* multiply dest */
			sxi(SX_MUL16X16SR8, 28, 60, 76, 15);
			/* add up */
			sxi(SX_ADDV, 44, 76, 92, 15);
			/* write back */
			if (rest < 4) {
				sxm(SX_STUQ0C, dstx, 92, rest - 1);
			} else {
				sxm(SX_STUQ0C, dstx, 92, 3);
			}
			dstx += 16;
			mskx += 16;
		}
#else /* SX_SINGLE */
		for (x = 0; x < width; x++) {
			m = *(volatile uint32_t *)(p->fb + mskx);
			m = m >> 24;
			if (m == 0) {
				/* nothing to do - all transparent */
			} else if (m == 0xff) {
				/* all opaque */
				sxm(SX_STUQ0, dstx, 8, 0);
			} else {
				/* fetch alpha value, stick it into scam */
				/* mask is in R[12:15] */
				/*write_sx_io(p, mskx,
				    SX_LDUQ0(12, 0, mskx & 7));*/
				write_sx_reg(p, SX_QUEUED(12), m);
				/* fetch dst pixel */
				sxm(SX_LDUQ0, dstx, 20, 0);
				sxi(SX_ORV, 12, 0, R_SCAM, 0);
				/*
				 * src * alpha + R0
				 * R[9:11] * SCAM + R0 -> R[17:19]
				 */
				sxi(SX_SAXP16X16SR8, 9, 0, 17, 2);

				/* invert SCAM */
				sxi(SX_XORV, 12, 8, R_SCAM, 0);
#ifdef SX_RENDER_DEBUG
				sxi(SX_XORV, 12, 8, 13, 0);
#endif
				/* dst * (1 - alpha) + R[13:15] */
				sxi(SX_SAXP16X16SR8, 21, 17, 25, 2);
				sxm(SX_STUQ0C, dstx, 24, 0);
			}
			dstx += 4;
			mskx += 4;
		}
#endif /* SX_SINGLE */
		dst += dstpitch;
		msk += srcpitch;
	}
}

void CG14Comp_Over8Solid(Cg14Ptr p,
                   uint32_t src, uint32_t srcpitch,
                   uint32_t dst, uint32_t dstpitch,
                   int width, int height)
{
	uint32_t msk = src, mskx, dstx, m;
	int line, x, i;
#ifdef SX_RENDER_VERBOSE
	char buffer[256];
#endif
	ENTER;

	DPRINTF(X_ERROR, "src: %d %d %d, %08x\n", read_sx_reg(p, SX_QUEUED(9)),
	    read_sx_reg(p, SX_QUEUED(10)), read_sx_reg(p, SX_QUEUED(11)),
	    *(uint32_t *)(p->fb + p->srcoff));
	for (line = 0; line < height; line++) {
		mskx = msk;
		dstx = dst;
#ifndef SX_SINGLE
		int rest;
		for (x = 0; x < width; x += 4) {
			rest = width - x;
			/* fetch 4 mask values */
			sxm(SX_LDB, mskx, 12, 3);
			/* fetch destination pixels */
			sxm(SX_LDUQ0, dstx, 60, 3);
			/* duplicate them for all channels */
			sxi(SX_ORS, 0, 13, 16, 3);
			sxi(SX_ORS, 0, 14, 20, 3);
			sxi(SX_ORS, 0, 15, 24, 3);
			sxi(SX_ORS, 0, 12, 13, 2);
			/* generate inverted alpha */
			sxi(SX_XORS, 12, 8, 28, 15);
			/* multiply source */
			sxi(SX_MUL16X16SR8, 8, 12, 44, 3);
			sxi(SX_MUL16X16SR8, 8, 16, 48, 3);
			sxi(SX_MUL16X16SR8, 8, 20, 52, 3);
			sxi(SX_MUL16X16SR8, 8, 24, 56, 3);
			/* multiply dest */
			sxi(SX_MUL16X16SR8, 28, 60, 76, 15);
			/* add up */
			sxi(SX_ADDV, 44, 76, 92, 15);
			/* write back */
			if (rest < 4) {
				sxm(SX_STUQ0C, dstx, 92, rest - 1);
			} else {
				sxm(SX_STUQ0C, dstx, 92, 3);
			}
			dstx += 16;
			mskx += 4;
		}
#else /* SX_SINGLE */
		for (x = 0; x < width; x++) {
			m = *(volatile uint8_t *)(p->fb + mskx);
#ifdef SX_RENDER_VERBOSE
			buffer[x] = c[m >> 5];
#endif
			if (m == 0) {
				/* nothing to do - all transparent */
			} else if (m == 0xff) {
				/* all opaque */
				sxm(SX_STUQ0, dstx, 8, 0);
			} else {
				/* fetch alpha value, stick it into scam */
				/* mask is in R[12:15] */
				/*write_sx_io(p, mskx & ~7,
				    SX_LDB(12, 0, mskx & 7));*/
				write_sx_reg(p, SX_QUEUED(12), m);
				/* fetch dst pixel */
				sxm(SX_LDUQ0, dstx, 20, 0);
				sxi(SX_ORV, 12, 0, R_SCAM, 0);
				/*
				 * src * alpha + R0
				 * R[9:11] * SCAM + R0 -> R[17:19]
				 */
				sxi(SX_SAXP16X16SR8, 9, 0, 17, 2);

				/* invert SCAM */
				sxi(SX_XORV, 12, 8, R_SCAM, 0);
#ifdef SX_RENDER_DEBUG
				sxi(SX_XORV, 12, 8, 13, 0);
#endif
				/* dst * (1 - alpha) + R[13:15] */
				sxi(SX_SAXP16X16SR8, 21, 17, 25, 2);
				sxm(SX_STUQ0C, dstx, 24, 0);
			}
			dstx += 4;
			mskx += 1;
		}
#endif /* SX_SINGLE */
#ifdef SX_RENDER_VERBOSE
		buffer[x] = 0;
		xf86Msg(X_ERROR, "%s\n", buffer);
#endif
		dst += dstpitch;
		msk += srcpitch;
	}
	DONE;
}

void CG14Comp_Add32(Cg14Ptr p,
                   uint32_t src, uint32_t srcpitch,
                   uint32_t dst, uint32_t dstpitch,
                   int width, int height)
{
	int line;
	uint32_t srcx, dstx;
	int full, part, x;

	ENTER;
	full = width >> 3;	/* chunks of 8 */
	part = width & 7;	/* leftovers */
	/* we do this up to 8 pixels at a time */
	for (line = 0; line < height; line++) {
		srcx = src;
		dstx = dst;
		for (x = 0; x < full; x++) {
			sxm(SX_LDUQ0, srcx, 8, 31);
			sxm(SX_LDUQ0, dstx, 40, 31);
			sxi(SX_ADDV, 8, 40, 72, 15);
			sxi(SX_ADDV, 24, 56, 88, 15);
			sxm(SX_STUQ0, dstx, 72, 31);
			srcx += 128;
			dstx += 128;
		}

		/* do leftovers */
		sxm(SX_LDUQ0, srcx, 8, part - 1);
		sxm(SX_LDUQ0, dstx, 40, part - 1);
		if (part & 16) {
			sxi(SX_ADDV, 8, 40, 72, 15);
			sxi(SX_ADDV, 24, 56, 88, part - 17);
		} else {
			sxi(SX_ADDV, 8, 40, 72, part - 1);
		}
		sxm(SX_STUQ0, dstx, 72, part - 1);

		/* next line */
		src += srcpitch;
		dst += dstpitch;
	}
}

void CG14Comp_Add8(Cg14Ptr p,
                   uint32_t src, uint32_t srcpitch,
                   uint32_t dst, uint32_t dstpitch,
                   int width, int height)
{
	int line;
	uint32_t srcx, dstx, srcoff, dstoff;
	int pre, full, part, x;
	uint8_t *d;
#ifdef SX_RENDER_VERBOSE
	char buffer[256];
#endif
	ENTER;

	srcoff = src & 7;
	src &= ~7;
	dstoff = dst & 7;
	dst &= ~7;
	full = width >> 5;	/* chunks of 32 */
	part = width & 31;	/* leftovers */

#ifdef SX_RENDER_DEBUG
	xf86Msg(X_ERROR, "%d %d, %d x %d, %d %d\n", srcpitch, dstpitch,
	    width, height, full, part);
#endif
	/* we do this up to 32 pixels at a time */
	for (line = 0; line < height; line++) {
		srcx = src;
		dstx = dst;
#ifdef SX_ADD_SOFTWARE
		uint8_t *s = (uint8_t *)(p->fb + srcx + srcoff);
		d = (uint8_t *)(p->fb + dstx + dstoff);
		for (x = 0; x < width; x++) {
			d[x] = min(255, s[x] + d[x]);
		}
#else
		for (x = 0; x < full; x++) {
			write_sx_io(p, srcx, SX_LDB(8, 31, srcoff));
			write_sx_io(p, dstx, SX_LDB(40, 31, dstoff));
			sxi(SX_ADDV, 8, 40, 72, 15);
			sxi(SX_ADDV, 24, 56, 88, 15);
			write_sx_io(p, dstx, SX_STBC(72, 31, dstoff));
			srcx += 32;
			dstx += 32;
		}

		if (part > 0) {
			/* do leftovers */
			write_sx_io(p, srcx, SX_LDB(8, part - 1, srcoff));
			write_sx_io(p, dstx, SX_LDB(40, part - 1, dstoff));
			if (part > 16) {
				sxi(SX_ADDV, 8, 40, 72, 15);
				sxi(SX_ADDV, 24, 56, 88, part - 17);
			} else {
				sxi(SX_ADDV, 8, 40, 72, part - 1);
			}
			write_sx_io(p, dstx, SX_STBC(72, part - 1, dstoff));
		}
#endif
#ifdef SX_RENDER_VERBOSE
		d = (uint8_t *)(p->fb + src + srcoff);
		for (x = 0; x < width; x++) {
			buffer[x] = c[d[x]>>5];
		}
		buffer[x] = 0;
		xf86Msg(X_ERROR, "%s\n", buffer);
#endif
		/* next line */
		src += srcpitch;
		dst += dstpitch;
	}
}

void CG14Comp_Add8_32(Cg14Ptr p,
                   uint32_t src, uint32_t srcpitch,
                   uint32_t dst, uint32_t dstpitch,
                   int width, int height)
{
	int line;
	uint32_t srcx, dstx, srcoff, dstoff;
	int pre, full, part, x;
	uint8_t *d;
#ifdef SX_RENDER_VERBOSE
	char buffer[256];
#endif
	ENTER;

	srcoff = src & 7;
	src &= ~7;
	dstoff = dst & 7;
	dst &= ~7;
	full = width >> 5;	/* chunks of 32 */
	part = width & 31;	/* leftovers */

#ifdef SX_RENDER_DEBUG
	xf86Msg(X_ERROR, "%d %d, %d x %d, %d %d\n", srcpitch, dstpitch,
	    width, height, full, part);
#endif
	/* we do this up to 32 pixels at a time */
	for (line = 0; line < height; line++) {
		srcx = src;
		dstx = dst;
		for (x = 0; x < full; x++) {
			/* load source bytes */
			write_sx_io(p, srcx, SX_LDB(8, 31, srcoff));
			/* load alpha from destination */
			write_sx_io(p, dstx, SX_LDUC0(40, 31, dstoff));
			sxi(SX_ADDV, 8, 40, 72, 15);
			sxi(SX_ADDV, 24, 56, 88, 15);
			/* write clamped values back into dest alpha */
			write_sx_io(p, dstx, SX_STUC0C(72, 31, dstoff));
			srcx += 32;
			dstx += 128;
		}

		if (part > 0) {
			/* do leftovers */
			write_sx_io(p, srcx, SX_LDB(8, part - 1, srcoff));
			write_sx_io(p, dstx, SX_LDUC0(40, part - 1, dstoff));
			if (part > 16) {
				sxi(SX_ADDV, 8, 40, 72, 15);
				sxi(SX_ADDV, 24, 56, 88, part - 17);
			} else {
				sxi(SX_ADDV, 8, 40, 72, part - 1);
			}
			write_sx_io(p, dstx, SX_STUC0C(72, part - 1, dstoff));
		}
#ifdef SX_RENDER_VERBOSE
		d = (uint8_t *)(p->fb + src + srcoff);
		for (x = 0; x < width; x++) {
			buffer[x] = c[d[x]>>5];
		}
		buffer[x] = 0;
		xf86Msg(X_ERROR, "%s\n", buffer);
#endif
		/* next line */
		src += srcpitch;
		dst += dstpitch;
	}
}

void CG14Comp_Over32(Cg14Ptr p,
                   uint32_t src, uint32_t srcpitch,
                   uint32_t dst, uint32_t dstpitch,
                   int width, int height, int flip)
{
	uint32_t srcx, dstx, mskx, m;
	int line, x, i, num;

	ENTER;

	write_sx_reg(p, SX_QUEUED(8), 0xff);
	for (line = 0; line < height; line++) {
		srcx = src;
		dstx = dst;

		for (x = 0; x < width; x += 4) {
			/* we do up to 4 pixels at a time */
			num = min(4, width - x);
			if (num <= 0) {
				xf86Msg(X_ERROR, "wtf?!\n");
				continue;
			}
			/* fetch source pixels */
			sxm(SX_LDUQ0, srcx, 12, num - 1);
			if (flip) {
				sxi(SX_GATHER, 13, 4, 40, num - 1);
				sxi(SX_GATHER, 15, 4, 44, num - 1);
				sxi(SX_SCATTER, 40, 4, 15, num - 1);
				sxi(SX_SCATTER, 44, 4, 13, num - 1);
			}
			/* fetch dst pixels */
			sxm(SX_LDUQ0, dstx, 44, num - 1);
			/* now process up to 4 pixels */
			for (i = 0; i < num; i++) {
				int ii = i << 2;
				/* write inverted alpha into SCAM */
				sxi(SX_XORS, 12 + ii, 8, R_SCAM, 0);
				/* dst * (1 - alpha) + src */
				sxi(SX_SAXP16X16SR8, 44 + ii, 12 + ii, 76 + ii, 3);
			}
			sxm(SX_STUQ0C, dstx, 76, num - 1);
			srcx += 16;
			dstx += 16;
		}
		src += srcpitch;
		dst += dstpitch;
	}
}

void CG14Comp_Over32Mask(Cg14Ptr p,
                   uint32_t src, uint32_t srcpitch,
                   uint32_t msk, uint32_t mskpitch,
                   uint32_t dst, uint32_t dstpitch,
                   int width, int height, int flip)
{
	uint32_t srcx, dstx, mskx, m;
	int line, x, i, num;

	ENTER;

	write_sx_reg(p, SX_QUEUED(8), 0xff);
	for (line = 0; line < height; line++) {
		srcx = src;
		mskx = msk;
		dstx = dst;

		for (x = 0; x < width; x += 4) {
			/* we do up to 4 pixels at a time */
			num = min(4, width - x);
			if (num <= 0) {
				xf86Msg(X_ERROR, "wtf?!\n");
				continue;
			}
			/* fetch source pixels */
			sxm(SX_LDUQ0, srcx, 12, num - 1);
			if (flip) {
				sxi(SX_GATHER, 13, 4, 40, num - 1);
				sxi(SX_GATHER, 15, 4, 44, num - 1);
				sxi(SX_SCATTER, 40, 4, 15, num - 1);
				sxi(SX_SCATTER, 44, 4, 13, num - 1);
			}
			/* fetch mask */
			sxm(SX_LDB, mskx, 28, num - 1);
			/* fetch dst pixels */
			sxm(SX_LDUQ0, dstx, 44, num - 1);
			/* now process up to 4 pixels */
			for (i = 0; i < num; i++) {
				int ii = i << 2;
				/* mask alpha to SCAM */
				sxi(SX_ORS, 28 + i, 0, R_SCAM, 0);
				/* src * alpha */
				sxi(SX_SAXP16X16SR8, 12 + ii, 0, 60 + ii, 3);
				/* write inverted alpha into SCAM */
				sxi(SX_XORS, 28 + i, 8, R_SCAM, 0);
				/* dst * (1 - alpha) + R[60:] */
				sxi(SX_SAXP16X16SR8, 44 + ii, 60 + ii, 76 + ii, 3);
			}
			sxm(SX_STUQ0C, dstx, 76, num - 1);
			srcx += 16;
			mskx += 4;
			dstx += 16;
		}
		src += srcpitch;
		msk += mskpitch;
		dst += dstpitch;
	}
}

void CG14Comp_Over32Mask_noalpha(Cg14Ptr p,
                   uint32_t src, uint32_t srcpitch,
                   uint32_t msk, uint32_t mskpitch,
                   uint32_t dst, uint32_t dstpitch,
                   int width, int height, int flip)
{
	uint32_t srcx, dstx, mskx, m;
	int line, x, i, num;

	ENTER;

	write_sx_reg(p, SX_QUEUED(8), 0xff);
	write_sx_reg(p, SX_QUEUED(9), 0xff);
	sxi(SX_ORS, 8, 0, 10, 1);
	for (line = 0; line < height; line++) {
		srcx = src;
		mskx = msk;
		dstx = dst;

		for (x = 0; x < width; x += 4) {
			/* we do up to 4 pixels at a time */
			num = min(4, width - x);
			if (num <= 0) {
				xf86Msg(X_ERROR, "wtf?!\n");
				continue;
			}
			/* fetch source pixels */
			sxm(SX_LDUQ0, srcx, 12, num - 1);
			if (flip) {
				sxi(SX_GATHER, 13, 4, 40, num - 1);
				sxi(SX_GATHER, 15, 4, 44, num - 1);
				sxi(SX_SCATTER, 40, 4, 15, num - 1);
				sxi(SX_SCATTER, 44, 4, 13, num - 1);
			}
			/* fetch mask */
			sxm(SX_LDB, mskx, 28, num - 1);
			/* fetch dst pixels */
			sxm(SX_LDUQ0, dstx, 44, num - 1);
			/* set src alpha to 0xff */
			sxi(SX_SCATTER, 8, 4, 12, num - 1);
			/* now process up to 4 pixels */
			for (i = 0; i < num; i++) {
				int ii = i << 2;
				/* mask alpha to SCAM */
				sxi(SX_ORS, 28 + i, 0, R_SCAM, 0);
				/* src * alpha */
				sxi(SX_SAXP16X16SR8, 12 + ii, 0, 60 + ii, 3);
				/* write inverted alpha into SCAM */
				sxi(SX_XORS, 28 + i, 8, R_SCAM, 0);
				/* dst * (1 - alpha) + R[60:] */
				sxi(SX_SAXP16X16SR8, 44 + ii, 60 + ii, 76 + ii, 3);
			}
			sxm(SX_STUQ0C, dstx, 76, num - 1);
			srcx += 16;
			mskx += 4;
			dstx += 16;
		}
		src += srcpitch;
		msk += mskpitch;
		dst += dstpitch;
	}
}

void CG14Comp_Over32Mask32_noalpha(Cg14Ptr p,
                   uint32_t src, uint32_t srcpitch,
                   uint32_t msk, uint32_t mskpitch,
                   uint32_t dst, uint32_t dstpitch,
                   int width, int height, int flip)
{
	uint32_t srcx, dstx, mskx, m;
	int line, x, i, num;

	ENTER;

	write_sx_reg(p, SX_QUEUED(8), 0xff);
	write_sx_reg(p, SX_QUEUED(9), 0xff);
	sxi(SX_ORS, 8, 0, 10, 1);
	for (line = 0; line < height; line++) {
		srcx = src;
		mskx = msk;
		dstx = dst;

		for (x = 0; x < width; x += 4) {
			/* we do up to 4 pixels at a time */
			num = min(4, width - x);
			if (num <= 0) {
				xf86Msg(X_ERROR, "wtf?!\n");
				continue;
			}
			/* fetch source pixels */
			sxm(SX_LDUQ0, srcx, 12, num - 1);
			if (flip) {
				sxi(SX_GATHER, 13, 4, 40, num - 1);
				sxi(SX_GATHER, 15, 4, 44, num - 1);
				sxi(SX_SCATTER, 40, 4, 15, num - 1);
				sxi(SX_SCATTER, 44, 4, 13, num - 1);
			}
			/* fetch mask */
			sxm(SX_LDUQ0, mskx, 28, num - 1);
			/* fetch dst pixels */
			sxm(SX_LDUQ0, dstx, 44, num - 1);
			/* set src alpha to 0xff */
			sxi(SX_SCATTER, 8, 4, 12, num - 1);
			/* now process up to 4 pixels */
			for (i = 0; i < num; i++) {
				int ii = i << 2;
				/* mask alpha to SCAM */
				sxi(SX_ORS, 28 + ii, 0, R_SCAM, 0);
				/* src * alpha */
				sxi(SX_SAXP16X16SR8, 12 + ii, 0, 60 + ii, 3);
				/* write inverted alpha into SCAM */
				sxi(SX_XORS, 28 + ii, 8, R_SCAM, 0);
				/* dst * (1 - alpha) + R[60:] */
				sxi(SX_SAXP16X16SR8, 44 + ii, 60 + ii, 76 + ii, 3);
			}
			sxm(SX_STUQ0C, dstx, 76, num - 1);
			srcx += 16;
			mskx += 16;
			dstx += 16;
		}
		src += srcpitch;
		msk += mskpitch;
		dst += dstpitch;
	}
}