src/hermes/x86_main.asm

   1 ;
   2 ; x86 format converters for HERMES
   3 ; Some routines Copyright (c) 1998 Christian Nentwich (brn@eleet.mcb.at)
   4 ; This source code is licensed under the GNU LGPL
   5 ;
   6 ; Please refer to the file COPYING.LIB contained in the distribution for
   7 ; licensing conditions
   8 ;
   9 ; Most routines are (c) Glenn Fiedler (ptc@gaffer.org), used with permission
  10 ;
  11
  12 BITS 32
  13
  14 %include "common.inc"
  15
  16 SDL_FUNC _ConvertX86
  17
  18 SECTION .text
  19
  20 ;; _ConvertX86:
  21 ;; [ESP+8] ConverterInfo*
  22 ;; --------------------------------------------------------------------------
  23 ;; ConverterInfo (ebp+..)
  24 ;;   0: void *s_pixels
  25 ;;   4: int s_width
  26 ;;   8: int s_height
  27 ;;  12: int s_add
  28 ;;  16: void *d_pixels
  29 ;;  20: int d_width
  30 ;;  24: int d_height
  31 ;;  28: int d_add
  32 ;;  32: void (*converter_function)()
  33 ;;  36: int32 *lookup
  34
  35 _ConvertX86:
  36         push ebp
  37         mov ebp,esp
  38
  39 ; Save the registers used by the blitters, necessary for optimized code
  40         pusha
  41
  42         mov eax,[ebp+8]
  43
  44         cmp dword [eax+4],BYTE 0
  45         je endconvert
  46
  47         mov ebp,eax
  48
  49         mov esi,[ebp+0]
  50         mov edi,[ebp+16]
  51
  52 y_loop:
  53         mov ecx,[ebp+4]
  54
  55         call [ebp+32]
  56
  57         add esi,[ebp+12]
  58         add edi,[ebp+28]
  59
  60         dec dword  [ebp+8]
  61         jnz y_loop
  62
  63 ; Restore the registers used by the blitters, necessary for optimized code
  64         popa
  65
  66         pop ebp
  67
  68 endconvert:
  69         ret
  70
  71
  72
  73 %ifidn __OUTPUT_FORMAT__,elf
  74 section .note.GNU-stack noalloc noexec nowrite progbits
  75 %endif