inffas86.c

gcc的组建

".L_invalid_distance_code:\n"
"        movl    $3, 72(%%esp)\n"
"        jmp     .L_break_loop_with_status\n"

".L_invalid_distance_too_far:\n"
"        movl    8(%%esp), %%esi\n"
"        movl    $4, 72(%%esp)\n"
"        jmp     .L_break_loop_with_status\n"

".L_break_loop:\n"
"        movl    $0, 72(%%esp)\n"

".L_break_loop_with_status:\n"
/* put in, out, bits, and hold back into ar and pop esp */
"        movl    %%esi, 8(%%esp)\n"      /* save in */
"        movl    %%edi, 16(%%esp)\n"     /* save out */
"        movl    %%ebx, 44(%%esp)\n"     /* save bits */
"        movl    %%edx, 40(%%esp)\n"     /* save hold */
"        movl    4(%%esp), %%ebp\n"      /* restore esp, ebp */
"        movl    (%%esp), %%esp\n"
          :
          : "m" (ar)
          : "memory", "%eax", "%ebx", "%ecx", "%edx", "%esi", "%edi"
    );
#elif defined( _MSC_VER ) && ! defined( _M_AMD64 )
    __asm {
	lea	eax, ar
	mov	[eax], esp         /* save esp, ebp */
	mov	[eax+4], ebp
	mov	esp, eax
	mov	esi, [esp+8]       /* esi = in */
	mov	edi, [esp+16]      /* edi = out */
	mov	edx, [esp+40]      /* edx = hold */
	mov	ebx, [esp+44]      /* ebx = bits */
	mov	ebp, [esp+32]      /* ebp = lcode */

	cld
	jmp	L_do_loop

ALIGN 4
L_while_test:
	cmp	[esp+24], edi
	jbe	L_break_loop
	cmp	[esp+12], esi
	jbe	L_break_loop

L_do_loop:
	cmp	bl, 15
	ja	L_get_length_code    /* if (15 < bits) */

	xor	eax, eax
	lodsw                         /* al = *(ushort *)in++ */
	mov	cl, bl            /* cl = bits, needs it for shifting */
	add	bl, 16             /* bits += 16 */
	shl	eax, cl
	or	edx, eax        /* hold |= *((ushort *)in)++ << bits */

L_get_length_code:
	mov	eax, [esp+56]      /* eax = lmask */
	and	eax, edx          /* eax &= hold */
	mov	eax, [ebp+eax*4] /* eax = lcode[hold & lmask] */

L_dolen:
	mov	cl, ah            /* cl = this.bits */
	sub	bl, ah            /* bits -= this.bits */
	shr	edx, cl           /* hold >>= this.bits */

	test	al, al
	jnz	L_test_for_length_base /* if (op != 0) 45.7% */

	shr	eax, 16            /* output this.val char */
	stosb
	jmp	L_while_test

ALIGN 4
L_test_for_length_base:
	mov	ecx, eax          /* len = this */
	shr	ecx, 16            /* len = this.val */
	mov	[esp+64], ecx      /* save len */
	mov	cl, al

	test	al, 16
	jz	L_test_for_second_level_length /* if ((op & 16) == 0) 8% */
	and	cl, 15             /* op &= 15 */
	jz	L_decode_distance    /* if (!op) */
	cmp	bl, cl
	jae	L_add_bits_to_len    /* if (op <= bits) */

	mov	ch, cl            /* stash op in ch, freeing cl */
	xor	eax, eax
	lodsw                         /* al = *(ushort *)in++ */
	mov	cl, bl            /* cl = bits, needs it for shifting */
	add	bl, 16             /* bits += 16 */
	shl	eax, cl
	or	edx, eax         /* hold |= *((ushort *)in)++ << bits */
	mov	cl, ch            /* move op back to ecx */

L_add_bits_to_len:
	sub	bl, cl
	xor	eax, eax
	inc	eax
	shl	eax, cl
	dec	eax
	and	eax, edx          /* eax &= hold */
	shr	edx, cl
	add	[esp+64], eax      /* len += hold & mask[op] */

L_decode_distance:
	cmp	bl, 15
	ja	L_get_distance_code  /* if (15 < bits) */

	xor	eax, eax
	lodsw                         /* al = *(ushort *)in++ */
	mov	cl, bl            /* cl = bits, needs it for shifting */
	add	bl, 16             /* bits += 16 */
	shl	eax, cl
	or	edx, eax         /* hold |= *((ushort *)in)++ << bits */

L_get_distance_code:
	mov	eax, [esp+60]      /* eax = dmask */
	mov	ecx, [esp+36]      /* ecx = dcode */
	and	eax, edx          /* eax &= hold */
	mov	eax, [ecx+eax*4]/* eax = dcode[hold & dmask] */

L_dodist:
	mov	ebp, eax          /* dist = this */
	shr	ebp, 16            /* dist = this.val */
	mov	cl, ah
	sub	bl, ah            /* bits -= this.bits */
	shr	edx, cl           /* hold >>= this.bits */
	mov	cl, al            /* cl = this.op */

	test	al, 16             /* if ((op & 16) == 0) */
	jz	L_test_for_second_level_dist
	and	cl, 15             /* op &= 15 */
	jz	L_check_dist_one
	cmp	bl, cl
	jae	L_add_bits_to_dist   /* if (op <= bits) 97.6% */

	mov	ch, cl            /* stash op in ch, freeing cl */
	xor	eax, eax
	lodsw                         /* al = *(ushort *)in++ */
	mov	cl, bl            /* cl = bits, needs it for shifting */
	add	bl, 16             /* bits += 16 */
	shl	eax, cl
	or	edx, eax        /* hold |= *((ushort *)in)++ << bits */
	mov	cl, ch            /* move op back to ecx */

L_add_bits_to_dist:
	sub	bl, cl
	xor	eax, eax
	inc	eax
	shl	eax, cl
	dec	eax                 /* (1 << op) - 1 */
	and	eax, edx          /* eax &= hold */
	shr	edx, cl
	add	ebp, eax          /* dist += hold & ((1 << op) - 1) */

L_check_window:
	mov	[esp+8], esi       /* save in so from can use it's reg */
	mov	eax, edi
	sub	eax, [esp+20]      /* nbytes = out - beg */

	cmp	eax, ebp
	jb	L_clip_window        /* if (dist > nbytes) 4.2% */

	mov	ecx, [esp+64]      /* ecx = len */
	mov	esi, edi
	sub	esi, ebp          /* from = out - dist */

	sar	ecx, 1
	jnc	L_copy_two

	rep     movsw
	mov	al, [esi]
	mov	[edi], al
	inc	edi

	mov	esi, [esp+8]      /* move in back to %esi, toss from */
	mov	ebp, [esp+32]     /* ebp = lcode */
	jmp	L_while_test

L_copy_two:
	rep     movsw
	mov	esi, [esp+8]      /* move in back to %esi, toss from */
	mov	ebp, [esp+32]     /* ebp = lcode */
	jmp	L_while_test

ALIGN 4
L_check_dist_one:
	cmp	ebp, 1            /* if dist 1, is a memset */
	jne	L_check_window
	cmp	[esp+20], edi
	je	L_check_window    /* out == beg, if outside window */

	mov	ecx, [esp+64]     /* ecx = len */
	mov	al, [edi-1]
	mov	ah, al

	sar	ecx, 1
	jnc	L_set_two
	mov	[edi], al         /* memset out with from[-1] */
	inc	edi

L_set_two:
	rep     stosw
	mov	ebp, [esp+32]     /* ebp = lcode */
	jmp	L_while_test

ALIGN 4
L_test_for_second_level_length:
	test	al, 64
	jnz	L_test_for_end_of_block /* if ((op & 64) != 0) */

	xor	eax, eax
	inc	eax
	shl	eax, cl
	dec	eax
	and	eax, edx         /* eax &= hold */
	add	eax, [esp+64]     /* eax += len */
	mov	eax, [ebp+eax*4] /* eax = lcode[val+(hold&mask[op])]*/
	jmp	L_dolen

ALIGN 4
L_test_for_second_level_dist:
	test	al, 64
	jnz	L_invalid_distance_code /* if ((op & 64) != 0) */

	xor	eax, eax
	inc	eax
	shl	eax, cl
	dec	eax
	and	eax, edx         /* eax &= hold */
	add	eax, ebp         /* eax += dist */
	mov	ecx, [esp+36]     /* ecx = dcode */
	mov	eax, [ecx+eax*4] /* eax = dcode[val+(hold&mask[op])]*/
	jmp	L_dodist

ALIGN 4
L_clip_window:
	mov	ecx, eax
	mov	eax, [esp+48]     /* eax = wsize */
	neg	ecx                /* nbytes = -nbytes */
	mov	esi, [esp+28]     /* from = window */

	cmp	eax, ebp
	jb	L_invalid_distance_too_far /* if (dist > wsize) */

	add	ecx, ebp         /* nbytes = dist - nbytes */
	cmp	dword ptr [esp+52], 0
	jne	L_wrap_around_window /* if (write != 0) */

	sub	eax, ecx
	add	esi, eax         /* from += wsize - nbytes */

	mov	eax, [esp+64]    /* eax = len */
	cmp	eax, ecx
	jbe	L_do_copy          /* if (nbytes >= len) */

	sub	eax, ecx         /* len -= nbytes */
	rep     movsb
	mov	esi, edi
	sub	esi, ebp         /* from = out - dist */
	jmp	L_do_copy

ALIGN 4
L_wrap_around_window:
	mov	eax, [esp+52]    /* eax = write */
	cmp	ecx, eax
	jbe	L_contiguous_in_window /* if (write >= nbytes) */

	add	esi, [esp+48]    /* from += wsize */
	add	esi, eax         /* from += write */
	sub	esi, ecx         /* from -= nbytes */
	sub	ecx, eax         /* nbytes -= write */

	mov	eax, [esp+64]    /* eax = len */
	cmp	eax, ecx
	jbe	L_do_copy          /* if (nbytes >= len) */

	sub	eax, ecx         /* len -= nbytes */
	rep     movsb
	mov	esi, [esp+28]     /* from = window */
	mov	ecx, [esp+52]     /* nbytes = write */
	cmp	eax, ecx
	jbe	L_do_copy          /* if (nbytes >= len) */

	sub	eax, ecx         /* len -= nbytes */
	rep     movsb
	mov	esi, edi
	sub	esi, ebp         /* from = out - dist */
	jmp	L_do_copy

ALIGN 4
L_contiguous_in_window:
	add	esi, eax
	sub	esi, ecx         /* from += write - nbytes */

	mov	eax, [esp+64]    /* eax = len */
	cmp	eax, ecx
	jbe	L_do_copy          /* if (nbytes >= len) */

	sub	eax, ecx         /* len -= nbytes */
	rep     movsb
	mov	esi, edi
	sub	esi, ebp         /* from = out - dist */
	jmp	L_do_copy

ALIGN 4
L_do_copy:
	mov	ecx, eax
	rep     movsb

	mov	esi, [esp+8]      /* move in back to %esi, toss from */
	mov	ebp, [esp+32]     /* ebp = lcode */
	jmp	L_while_test

L_test_for_end_of_block:
	test	al, 32
	jz	L_invalid_literal_length_code
	mov	dword ptr [esp+72], 1
	jmp	L_break_loop_with_status

L_invalid_literal_length_code:
	mov	dword ptr [esp+72], 2
	jmp	L_break_loop_with_status

L_invalid_distance_code:
	mov	dword ptr [esp+72], 3
	jmp	L_break_loop_with_status

L_invalid_distance_too_far:
	mov	esi, [esp+4]
	mov	dword ptr [esp+72], 4
	jmp	L_break_loop_with_status

L_break_loop:
	mov	dword ptr [esp+72], 0

L_break_loop_with_status:
/* put in, out, bits, and hold back into ar and pop esp */
	mov	[esp+8], esi     /* save in */
	mov	[esp+16], edi    /* save out */
	mov	[esp+44], ebx    /* save bits */
	mov	[esp+40], edx    /* save hold */
	mov	ebp, [esp+4]     /* restore esp, ebp */
	mov	esp, [esp]
    }
#else
#error "x86 architecture not defined"
#endif

    if (ar.status > 1) {
        if (ar.status == 2)
            strm->msg = "invalid literal/length code";
        else if (ar.status == 3)
            strm->msg = "invalid distance code";
        else
            strm->msg = "invalid distance too far back";
        state->mode = BAD;
    }
    else if ( ar.status == 1 ) {
        state->mode = TYPE;
    }

    /* return unused bytes (on entry, bits < 8, so in won't go too far back) */
    ar.len = ar.bits >> 3;
    ar.in -= ar.len;
    ar.bits -= ar.len << 3;
    ar.hold &= (1U << ar.bits) - 1;

    /* update state and return */
    strm->next_in = ar.in;
    strm->next_out = ar.out;
    strm->avail_in = (unsigned)(ar.in < ar.last ?
                                PAD_AVAIL_IN + (ar.last - ar.in) :
                                PAD_AVAIL_IN - (ar.in - ar.last));
    strm->avail_out = (unsigned)(ar.out < ar.end ?
                                 PAD_AVAIL_OUT + (ar.end - ar.out) :
                                 PAD_AVAIL_OUT - (ar.out - ar.end));
    state->hold = ar.hold;
    state->bits = ar.bits;
    return;
}