initial commit, 4.5 stable

thirdparty/libpng/loongarch/loongarch_lsx_init.c

@@ -0,0 +1,65 @@
+/* loongarch_lsx_init.c - LSX optimized filter functions
+ *
+ * Copyright (c) 2021 Loongson Technology Corporation Limited
+ * All rights reserved.
+ * Contributed by Jin Bo <jinbo@loongson.cn>
+ *
+ * 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_LOONGARCH_LSX_IMPLEMENTATION == 1
+
+#include <sys/auxv.h>
+
+#define LA_HWCAP_LSX    (1<<4)
+static int png_has_lsx(void)
+{
+    int flags = 0;
+    int flag  = (int)getauxval(AT_HWCAP);
+
+    if (flag & LA_HWCAP_LSX)
+        return 1;
+
+    return 0;
+}
+
+void
+png_init_filter_functions_lsx(png_structp pp, unsigned int bpp)
+{
+   /* 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.)
+    */
+
+   if (png_has_lsx())
+   {
+      pp->read_filter[PNG_FILTER_VALUE_UP-1] = png_read_filter_row_up_lsx;
+      if (bpp == 3)
+      {
+         pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub3_lsx;
+         pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg3_lsx;
+         pp->read_filter[PNG_FILTER_VALUE_PAETH-1] = png_read_filter_row_paeth3_lsx;
+      }
+      else if (bpp == 4)
+      {
+         pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub4_lsx;
+         pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg4_lsx;
+         pp->read_filter[PNG_FILTER_VALUE_PAETH-1] = png_read_filter_row_paeth4_lsx;
+      }
+   }
+}
+
+#endif /* PNG_LOONGARCH_LSX_IMPLEMENTATION == 1 */
+#endif /* PNG_READ_SUPPORTED */