;

; x86 format converters for HERMES

; Copyright (c) 1998 Glenn Fielder (gaffer@gaffer.org)

; This source code is licensed under the GNU LGPL

; 

; Please refer to the file COPYING.LIB contained in the distribution for

; licensing conditions		

; 

; Routines adjusted for Hermes by Christian Nentwich (brn@eleet.mcb.at)

; Used with permission.

; 

BITS 32

%include "common.inc"

SDL_FUNC _ConvertX86p16_16BGR565

SDL_FUNC _ConvertX86p16_16RGB555

SDL_FUNC _ConvertX86p16_16BGR555

SDL_FUNC _ConvertX86p16_8RGB332

EXTERN _ConvertX86

SECTION .text

_ConvertX86p16_16BGR565:

    ; check short

    cmp ecx,BYTE 16

    ja .L3

.L1 ; short loop

    mov al,[esi]

    mov ah,[esi+1]

    mov ebx,eax

    mov edx,eax

    shr eax,11

    and eax,BYTE 11111b

    and ebx,11111100000b

    shl edx,11

    add eax,ebx

    add eax,edx

    mov [edi],al

    mov [edi+1],ah

    add esi,BYTE 2

    add edi,BYTE 2

    dec ecx

    jnz .L1

.L2

    retn

.L3 ; head

    mov eax,edi

    and eax,BYTE 11b

    jz .L4

    mov al,[esi]

    mov ah,[esi+1]

    mov ebx,eax

    mov edx,eax

    shr eax,11

    and eax,BYTE 11111b

    and ebx,11111100000b

    shl edx,11

    add eax,ebx

    add eax,edx

    mov [edi],al

    mov [edi+1],ah

    add esi,BYTE 2

    add edi,BYTE 2

    dec ecx

.L4 ; save count

    push ecx

    ; unroll twice

    shr ecx,1

    ; point arrays to end

    lea esi,[esi+ecx*4]

    lea edi,[edi+ecx*4]

    ; negative counter 

    neg ecx

    jmp SHORT .L6

.L5     mov [edi+ecx*4-4],eax

.L6     mov eax,[esi+ecx*4]

        mov ebx,[esi+ecx*4]

        and eax,07E007E0h         

        mov edx,[esi+ecx*4]

        and ebx,0F800F800h

        shr ebx,11

        and edx,001F001Fh

        shl edx,11

        add eax,ebx

        add eax,edx                 

        inc ecx

        jnz .L5                 

    mov [edi+ecx*4-4],eax

    ; tail

    pop ecx

    and ecx,BYTE 1

    jz .L7

    mov al,[esi]

    mov ah,[esi+1]

    mov ebx,eax

    mov edx,eax

    shr eax,11

    and eax,BYTE 11111b

    and ebx,11111100000b

    shl edx,11

    add eax,ebx

    add eax,edx

    mov [edi],al

    mov [edi+1],ah

    add esi,BYTE 2

    add edi,BYTE 2

.L7

    retn

_ConvertX86p16_16RGB555:

    ; check short

    cmp ecx,BYTE 32

    ja .L3

.L1 ; short loop

    mov al,[esi]

    mov ah,[esi+1]

    mov ebx,eax

    shr ebx,1

    and ebx,     0111111111100000b

    and eax,BYTE 0000000000011111b

    add eax,ebx

    mov [edi],al

    mov [edi+1],ah

    add esi,BYTE 2

    add edi,BYTE 2

    dec ecx

    jnz .L1

.L2

    retn

.L3 ; head

    mov eax,edi

    and eax,BYTE 11b

    jz .L4

    mov al,[esi]

    mov ah,[esi+1]

    mov ebx,eax

    shr ebx,1

    and ebx,     0111111111100000b

    and eax,BYTE 0000000000011111b

    add eax,ebx

    mov [edi],al

    mov [edi+1],ah

    add esi,BYTE 2

    add edi,BYTE 2

    dec ecx

.L4 ; save ebp

    push ebp

    ; save count

    push ecx

    ; unroll four times

    shr ecx,2

    ; point arrays to end

    lea esi,[esi+ecx*8]

    lea edi,[edi+ecx*8]

    ; negative counter 

    xor ebp,ebp

    sub ebp,ecx

.L5     mov eax,[esi+ebp*8]        ; agi?

        mov ecx,[esi+ebp*8+4]

        mov ebx,eax

        mov edx,ecx

        and eax,0FFC0FFC0h

        and ecx,0FFC0FFC0h

        shr eax,1

        and ebx,001F001Fh

        shr ecx,1

        and edx,001F001Fh

        add eax,ebx

        add ecx,edx

        mov [edi+ebp*8],eax

        mov [edi+ebp*8+4],ecx

        inc ebp

        jnz .L5                 

    ; tail

    pop ecx

.L6 and ecx,BYTE 11b

    jz .L7

    mov al,[esi]

    mov ah,[esi+1]

    mov ebx,eax

    shr ebx,1

    and ebx,     0111111111100000b

    and eax,BYTE 0000000000011111b

    add eax,ebx

    mov [edi],al

    mov [edi+1],ah

    add esi,BYTE 2

    add edi,BYTE 2

    dec ecx

    jmp SHORT .L6

.L7 pop ebp

    retn

_ConvertX86p16_16BGR555:

    ; check short

    cmp ecx,BYTE 16

    ja .L3

.L1 ; short loop

    mov al,[esi]

    mov ah,[esi+1]

    mov ebx,eax

    mov edx,eax

    shr eax,11

    and eax,BYTE 11111b

    shr ebx,1

    and ebx,1111100000b

    shl edx,10

    and edx,0111110000000000b

    add eax,ebx

    add eax,edx

    mov [edi],al

    mov [edi+1],ah

    add esi,BYTE 2

    add edi,BYTE 2

    dec ecx

    jnz .L1

.L2

    retn

.L3 ; head

    mov eax,edi

    and eax,BYTE 11b

    jz .L4

    mov al,[esi]

    mov ah,[esi+1]

    mov ebx,eax

    mov edx,eax

    shr eax,11

    and eax,BYTE 11111b

    shr ebx,1

    and ebx,1111100000b

    shl edx,10

    and edx,0111110000000000b

    add eax,ebx

    add eax,edx

    mov [edi],al

    mov [edi+1],ah

    add esi,BYTE 2

    add edi,BYTE 2

    dec ecx

.L4 ; save count

    push ecx

    ; unroll twice

    shr ecx,1

    ; point arrays to end

    lea esi,[esi+ecx*4]

    lea edi,[edi+ecx*4]

    ; negative counter 

    neg ecx

    jmp SHORT .L6

.L5     mov [edi+ecx*4-4],eax

.L6     mov eax,[esi+ecx*4]

        shr eax,1

        mov ebx,[esi+ecx*4]

        and eax,03E003E0h         

        mov edx,[esi+ecx*4]

        and ebx,0F800F800h

        shr ebx,11

        and edx,001F001Fh

        shl edx,10

        add eax,ebx

        add eax,edx                 

        inc ecx

        jnz .L5                 

    mov [edi+ecx*4-4],eax

    ; tail

    pop ecx

    and ecx,BYTE 1

    jz .L7

    mov al,[esi]

    mov ah,[esi+1]

    mov ebx,eax

    mov edx,eax

    shr eax,11

    and eax,BYTE 11111b

    shr ebx,1

    and ebx,1111100000b

    shl edx,10

    and edx,0111110000000000b

    add eax,ebx

    add eax,edx

    mov [edi],al

    mov [edi+1],ah

    add esi,BYTE 2

    add edi,BYTE 2

.L7

    retn

_ConvertX86p16_8RGB332:

    ; check short

    cmp ecx,BYTE 16

    ja .L3

.L1 ; short loop

    mov al,[esi+0]

    mov ah,[esi+1]

    mov ebx,eax

    mov edx,eax

    and eax,BYTE 11000b         ; blue

    shr eax,3

    and ebx,11100000000b        ; green

    shr ebx,6

    and edx,1110000000000000b   ; red

    shr edx,8

    add eax,ebx

    add eax,edx

    mov [edi],al

    add esi,BYTE 2

    inc edi

    dec ecx

    jnz .L1

.L2

    retn

.L3 mov eax,edi

    and eax,BYTE 11b

    jz .L4

    mov al,[esi+0]

    mov ah,[esi+1]

    mov ebx,eax

    mov edx,eax

    and eax,BYTE 11000b         ; blue

    shr eax,3

    and ebx,11100000000b        ; green

    shr ebx,6

    and edx,1110000000000000b   ; red

    shr edx,8

    add eax,ebx

    add eax,edx

    mov [edi],al

    add esi,BYTE 2

    inc edi

    dec ecx

    jmp SHORT .L3

.L4 ; save ebp

    push ebp

    ; save count

    push ecx

    ; unroll 4 times

    shr ecx,2

    ; prestep

    mov dl,[esi+0]

    mov bl,[esi+1]

    mov dh,[esi+2]

.L5     shl edx,16

        mov bh,[esi+3]

        shl ebx,16

        mov dl,[esi+4]

        mov dh,[esi+6]

        mov bl,[esi+5]

        and edx,00011000000110000001100000011000b

        mov bh,[esi+7]

        ror edx,16+3

        mov eax,ebx                                     ; setup eax for reds

        and ebx,00000111000001110000011100000111b

        and eax,11100000111000001110000011100000b       ; reds

        ror ebx,16-2

        add esi,BYTE 8

        ror eax,16

        add edi,BYTE 4

        add eax,ebx

        mov bl,[esi+1]                                  ; greens

        add eax,edx

        mov dl,[esi+0]                                  ; blues

        mov [edi-4],eax

        mov dh,[esi+2]

        dec ecx

        jnz .L5                 

    ; check tail

    pop ecx

    and ecx,BYTE 11b

    jz .L7

.L6 ; tail

    mov al,[esi+0]

    mov ah,[esi+1]

    mov ebx,eax

    mov edx,eax

    and eax,BYTE 11000b         ; blue

    shr eax,3

    and ebx,11100000000b        ; green

    shr ebx,6

    and edx,1110000000000000b   ; red

    shr edx,8

    add eax,ebx

    add eax,edx

    mov [edi],al

    add esi,BYTE 2

    inc edi

    dec ecx

    jnz .L6

.L7 pop ebp

    retn

%ifidn __OUTPUT_FORMAT__,elf

section .note.GNU-stack noalloc noexec nowrite progbits

%endif