rom-properties/extlib/libpng/riscv/riscv_init.c
David Korth c3643b9244 [libpng] Update: v1.6.48 -> v1.6.49
Includes the APNG patch.
2025-06-15 14:25:09 -04:00

127 lines
4.3 KiB
C
Vendored

/* riscv_init.c - RISC-V Vector optimized filter functions
*
* Copyright (c) 2023 Google LLC
* Written by Dragoș Tiselice <dtiselice@google.com>, May 2023.
* Filip Wasil <f.wasil@samsung.com>, March 2025.
* This code is released under the libpng license.
* For conditions of distribution and use, see the disclaimer
* and license in png.h
*/
#include "../pngpriv.h"
#ifdef PNG_READ_SUPPORTED
#if PNG_RISCV_RVV_OPT > 0
#include <riscv_vector.h>
#ifdef PNG_RISCV_RVV_CHECK_SUPPORTED /* Do run-time checks */
/* WARNING: it is strongly recommended that you do not build libpng with
* run-time checks for CPU features if at all possible. In the case of the
* RISC-V Vector instructions there is no processor-specific way of detecting
* the presence of the required support, therefore run-time detection is
* extremely OS specific.
*
* You may set the macro PNG_RISCV_RVV_FILE to the file name of file containing
* a fragment of C source code which defines the png_have_rvv function. There
* are a number of implementations in contrib/riscv-rvv, but the only one that
* has partial support is contrib/riscv-rvv/linux.c - a generic Linux
* implementation which reads /proc/cpuinfo.
*/
#include <signal.h>
#ifndef PNG_RISCV_RVV_FILE
# if defined(__linux__)
# define PNG_RISCV_RVV_FILE "contrib/riscv-rvv/linux.c"
# else
# error "No support for run-time RISC-V Vector checking; use compile-time options"
# endif
#endif
static int png_have_rvv(png_structp png_ptr);
#ifdef PNG_RISCV_RVV_FILE
# include PNG_RISCV_RVV_FILE
#endif
#endif /* PNG_RISCV_RVV_CHECK_SUPPORTED */
#ifndef PNG_ALIGNED_MEMORY_SUPPORTED
# error "ALIGNED_MEMORY is required; set: -DPNG_ALIGNED_MEMORY_SUPPORTED"
#endif
void
png_init_filter_functions_rvv(png_structp pp, unsigned int bpp)
{
/* The switch statement is compiled in for RISCV_RVV_API, the call to
* png_have_rvv is compiled in for RISCV_RVV_CHECK. If both are
* defined the check is only performed if the API has not set the VECTOR
* option on or off explicitly. In this case the check controls what
* happens.
*/
png_debug(1, "in png_init_filter_functions_rvv");
#ifdef PNG_RISCV_RVV_API_SUPPORTED
switch ((pp->options >> PNG_RISCV_RVV) & 3)
{
case PNG_OPTION_UNSET:
/* Allow the run-time check to execute if it has been enabled -
* thus both API and CHECK can be turned on. If it isn't supported
* this case will fall through to the 'default' below, which just
* returns.
*/
#endif /* PNG_RISCV_RVV_API_SUPPORTED */
#ifdef PNG_RISCV_RVV_CHECK_SUPPORTED
{
static volatile sig_atomic_t no_rvv = -1; /* not checked */
if (no_rvv < 0)
no_rvv = !png_have_rvv(pp);
if (no_rvv)
return;
}
#ifdef PNG_RISCV_RVV_API_SUPPORTED
break;
#endif
#endif /* PNG_RISCV_RVV_CHECK_SUPPORTED */
#ifdef PNG_RISCV_RVV_API_SUPPORTED
default: /* OFF or INVALID */
return;
case PNG_OPTION_ON:
/* Option turned on */
break;
}
#endif /* PNG_RISCV_RVV_API_SUPPORTED */
/* IMPORTANT: any new external functions used here must be declared using
* PNG_INTERNAL_FUNCTION in ../pngpriv.h. This is required so that the
* 'prefix' option to configure works:
*
* ./configure --with-libpng-prefix=foobar_
*
* Verify you have got this right by running the above command, doing a build
* and examining pngprefix.h; it must contain a #define for every external
* function you add. (Notice that this happens automatically for the
* initialization function.)
*/
pp->read_filter[PNG_FILTER_VALUE_UP-1] = png_read_filter_row_up_rvv;
if (bpp == 3)
{
pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg3_rvv;
pp->read_filter[PNG_FILTER_VALUE_PAETH-1] = png_read_filter_row_paeth3_rvv;
pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub3_rvv;
}
else if (bpp == 4)
{
pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg4_rvv;
pp->read_filter[PNG_FILTER_VALUE_PAETH-1] = png_read_filter_row_paeth4_rvv;
pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub4_rvv;
}
}
#endif /* PNG_RISCV_RVV_OPT > 0 */
#endif /* PNG_READ_SUPPORTED */