[thirdparty/glibc.git] / sysdeps / i386 / strtok.S

/* strtok (str, delim) -- Return next DELIM separated token from STR.
For Intel 80x86, x>=3.
Copyright (C) 1996 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.

The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.

The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Library General Public License for more details.

You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB.  If
not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.  */

#include <sysdep.h>

/* This file can be used for three variants of the strtok function:

   strtok:
	INPUT PARAMETER:
	str		(sp + 4)
	delim		(sp + 8)

   strtok_r:
	INPUT PARAMETER:
	str		(sp + 4)
	delim		(sp + 8)
	save_ptr	(sp + 12)

   We do a common implementation here.  */

#ifndef USE_AS_STRTOK_R
	.bss
	.local save_ptr
	ASM_TYPE_DIRECTIVE (save_ptr, @object)
	.size save_ptr, 4
save_ptr:
	.space 4

#define FUNCTION strtok
#endif

	.text

ENTRY (FUNCTION)

	movl 4(%esp), %edx		/* Get start of string.  */
	movl 8(%esp), %eax		/* Get start of delimiter set.  */

#if !defined (USE_AS_STRTOK_R) && defined (PIC)
	pushl %ebx			/* Save PIC register.  */
	call Lhere
Lhere:	popl %ebx
	addl $_GLOBAL_OFFSET_TABLE_+[.-Lhere], %ebx
#endif

	/* If the pointer is NULL we have to use the stored value of
	   the last run.  */
	cmpl $0, %edx
	jne L0

#ifdef USE_AS_STRTOK_R
	/* The value is stored in the third argument.  */
	movl 12(%esp), %edx
	movl (%edx), %edx
#else
	/* The value is in the local variable defined above.  But
	   we have to take care for PIC code.  */
# ifndef PIC
	movl save_ptr, %edx
# else
	movl save_ptr@GOTOFF(%ebx), %edx
# endif
#endif

L0:
	/* First we create a table with flags for all possible characters.
	   For the ASCII (7bit/8bit) or ISO-8859-X character sets which are
	   supported by the C string functions we have 256 characters.
	   Before inserting marks for the stop characters we clear the whole
	   table.  The unrolled form is much faster than a loop.  */
	xorl %ecx, %ecx		/* %ecx = 0 !!! */

	pushl %ecx		/* make a 256 bytes long block filled with 0 */
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl %ecx
	pushl $0		/* These immediate values make the label 2 */
	pushl $0		/* to be aligned on a 16 byte boundary to */
	pushl $0		/* get a better performance of the loop.  */
	pushl $0
	pushl $0
	pushl $0

/* For understanding the following code remember that %ecx == 0 now.
   Although all the following instruction only modify %cl we always
   have a correct zero-extended 32-bit value in %ecx.  */

L2:	movb (%eax), %cl	/* get byte from stopset */
	testb %cl, %cl		/* is NUL char? */
	jz L1			/* yes => start compare loop */
	movb %cl, (%esp,%ecx)	/* set corresponding byte in stopset table */

	movb 1(%eax), %cl	/* get byte from stopset */
	testb $0xff, %cl	/* is NUL char? */
	jz L1			/* yes => start compare loop */
	movb %cl, (%esp,%ecx)	/* set corresponding byte in stopset table */

	movb 2(%eax), %cl	/* get byte from stopset */
	testb $0xff, %cl	/* is NUL char? */
	jz L1			/* yes => start compare loop */
	movb %cl, (%esp,%ecx)	/* set corresponding byte in stopset table */

	movb 3(%eax), %cl	/* get byte from stopset */
	addl $4, %eax		/* increment stopset pointer */
	movb %cl, (%esp,%ecx)	/* set corresponding byte in stopset table */
	testb $0xff, %cl	/* is NUL char? */
	jnz L2			/* no => process next dword from stopset */

L1:	leal -4(%edx), %eax	/* prepare loop */

	/* We use a neat trick for the following loop.  Normally we would
	   have to test for two termination conditions
	   1. a character in the stopset was found
	   and
	   2. the end of the string was found
	   As a sign that the character is in the stopset we store its
	   value in the table.  The value of NUL is NUL so the loop
	   terminates for NUL in every case.  */

L3:	addl $4, %eax		/* adjust pointer for full loop round */

	movb (%eax), %cl	/* get byte from string */
	testb %cl, (%esp,%ecx)	/* is it contained in stopset? */
	jz L4			/* no => start of token */

	movb 1(%eax), %cl	/* get byte from string */
	testb %cl, (%esp,%ecx)	/* is it contained in stopset? */
	jz L5			/* no => start of token */

	movb 2(%eax), %cl	/* get byte from string */
	testb %cl, (%esp,%ecx)	/* is it contained in stopset? */
	jz L6			/* no => start of token */

	movb 3(%eax), %cl	/* get byte from string */
	testb %cl, (%esp,%ecx)	/* is it contained in stopset? */
	jnz L3			/* yes => start of loop */

	incl %eax		/* adjust pointer */
L6:	incl %eax
L5:	incl %eax

	/* Now we have to terminate the string.  */

L4:	leal -4(%eax), %edx	/* We use %EDX for the next run.  */

L7:	addl $4, %edx		/* adjust pointer for full loop round */

	movb (%edx), %cl	/* get byte from string */
	cmpb %cl, (%esp,%ecx)	/* is it contained in skipset? */
	je L8			/* yes => return */

	movb 1(%edx), %cl	/* get byte from string */
	cmpb %cl, (%esp,%ecx)	/* is it contained in skipset? */
	je L9			/* yes => return */

	movb 2(%edx), %cl	/* get byte from string */
	cmpb %cl, (%esp,%ecx)	/* is it contained in skipset? */
	je L10			/* yes => return */

	movb 3(%edx), %cl	/* get byte from string */
	cmpb %cl, (%esp,%ecx)	/* is it contained in skipset? */
	jne L7			/* no => start loop again */

	incl %edx		/* adjust pointer */
L10:	incl %edx
L9:	incl %edx

L8:	/* Remove the stopset table.  */
	addl $256, %esp

	cmpl %eax, %edx
	je LreturnNULL		/* There was no token anymore.  */

	movb $0, (%edx)		/* Terminate string.  */

	/* Are we at end of string?  */
	cmpb $0, %cl
	je L11

	incl %edx
L11:

	/* Store the pointer to the next character.  */
#ifdef USE_AS_STRTOK_R
	movl 12(%esp), %ecx
	movl %edx, (%ecx)
#else
# ifndef PIC
	movl %edx, save_ptr
# else
	movl %edx, save_ptr@GOTOFF(%ebx)
	popl %ebx
# endif
#endif
	ret

LreturnNULL:
	xorl %eax, %eax

	/* Store current pointer for next round.  */
#ifdef USE_AS_STRTOK_R
	movl 12(%esp), %ecx
	movl %edx, (%ecx)
#else
# ifndef PIC
	movl %edx, save_ptr
# else
	movl %edx, save_ptr@GOTOFF(%ebx)
	popl %ebx
# endif
#endif
	ret
PSEUDO_END (FUNCTION)
Commit	Line	Data
59dd8641 RM	1	/* strtok (str, delim) -- Return next DELIM separated token from STR.
	2	For Intel 80x86, x>=3.
	3	Copyright (C) 1996 Free Software Foundation, Inc.
	4	This file is part of the GNU C Library.
	5	Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
	6
	7	The GNU C Library is free software; you can redistribute it and/or
	8	modify it under the terms of the GNU Library General Public License as
	9	published by the Free Software Foundation; either version 2 of the
	10	License, or (at your option) any later version.
	11
	12	The GNU C Library is distributed in the hope that it will be useful,
	13	but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	15	Library General Public License for more details.
	16
	17	You should have received a copy of the GNU Library General Public
	18	License along with the GNU C Library; see the file COPYING.LIB. If
	19	not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
	20	Boston, MA 02111-1307, USA. */
	21
59dd8641 RM	22	#include <sysdep.h>
	23
	24	/* This file can be used for three variants of the strtok function:
	25
	26	strtok:
	27	INPUT PARAMETER:
	28	str (sp + 4)
	29	delim (sp + 8)
	30
	31	strtok_r:
	32	INPUT PARAMETER:
	33	str (sp + 4)
	34	delim (sp + 8)
	35	save_ptr (sp + 12)
	36
59dd8641 RM	37	We do a common implementation here. */
59dd8641 RM	38
76060ec0	39	#ifndef USE_AS_STRTOK_R
59dd8641 RM	40	.bss
	41	.local save_ptr
	42	ASM_TYPE_DIRECTIVE (save_ptr, @object)
	43	.size save_ptr, 4
	44	save_ptr:
	45	.space 4
	46
	47	#define FUNCTION strtok
	48	#endif
	49
59dd8641	50	.text
59dd8641 RM	51
	52	ENTRY (FUNCTION)
	53
	54	movl 4(%esp), %edx /* Get start of string. */
	55	movl 8(%esp), %eax /* Get start of delimiter set. */
	56
76060ec0	57	#if !defined (USE_AS_STRTOK_R) && defined (PIC)
59dd8641 RM	58	pushl %ebx /* Save PIC register. */
	59	call Lhere
	60	Lhere: popl %ebx
	61	addl $_GLOBAL_OFFSET_TABLE_+[.-Lhere], %ebx
76060ec0	62	#endif
59dd8641 RM	63
	64	/* If the pointer is NULL we have to use the stored value of
	65	the last run. */
	66	cmpl $0, %edx
	67	jne L0
	68
76060ec0	69	#ifdef USE_AS_STRTOK_R
59dd8641 RM	70	/* The value is stored in the third argument. */
	71	movl 12(%esp), %edx
	72	movl (%edx), %edx
76060ec0	73	#else
59dd8641 RM	74	/* The value is in the local variable defined above. But
59dd8641 RM	75	we have to take care for PIC code. */
76060ec0	76	# ifndef PIC
59dd8641	77	movl save_ptr, %edx
76060ec0	78	# else
59dd8641	79	movl save_ptr@GOTOFF(%ebx), %edx
59dd8641 RM	80	# endif
	81	#endif
	82
59dd8641	83	L0:
59dd8641 RM	84	/* First we create a table with flags for all possible characters.
	85	For the ASCII (7bit/8bit) or ISO-8859-X character sets which are
	86	supported by the C string functions we have 256 characters.
	87	Before inserting marks for the stop characters we clear the whole
	88	table. The unrolled form is much faster than a loop. */
	89	xorl %ecx, %ecx /* %ecx = 0 !!! */
	90
	91	pushl %ecx /* make a 256 bytes long block filled with 0 */
	92	pushl %ecx
	93	pushl %ecx
	94	pushl %ecx
	95	pushl %ecx
	96	pushl %ecx
	97	pushl %ecx
	98	pushl %ecx
	99	pushl %ecx
	100	pushl %ecx
	101	pushl %ecx
	102	pushl %ecx
	103	pushl %ecx
	104	pushl %ecx
	105	pushl %ecx
	106	pushl %ecx
	107	pushl %ecx
	108	pushl %ecx
	109	pushl %ecx
	110	pushl %ecx
	111	pushl %ecx
	112	pushl %ecx
	113	pushl %ecx
	114	pushl %ecx
	115	pushl %ecx
	116	pushl %ecx
	117	pushl %ecx
	118	pushl %ecx
	119	pushl %ecx
	120	pushl %ecx
	121	pushl %ecx
	122	pushl %ecx
	123	pushl %ecx
	124	pushl %ecx
	125	pushl %ecx
	126	pushl %ecx
	127	pushl %ecx
	128	pushl %ecx
	129	pushl %ecx
	130	pushl %ecx
	131	pushl %ecx
	132	pushl %ecx
	133	pushl %ecx
	134	pushl %ecx
	135	pushl %ecx
	136	pushl %ecx
	137	pushl %ecx
	138	pushl %ecx
	139	pushl %ecx
	140	pushl %ecx
	141	pushl %ecx
	142	pushl %ecx
	143	pushl %ecx
	144	pushl %ecx
	145	pushl %ecx
	146	pushl %ecx
	147	pushl %ecx
148	pushl %ecx
149	pushl $0 /* These immediate values make the label 2 */
150	pushl $0 /* to be aligned on a 16 byte boundary to */
151	pushl $0 /* get a better performance of the loop. */
152	pushl $0
153	pushl $0
154	pushl $0
155
156	/* For understanding the following code remember that %ecx == 0 now.
157	Although all the following instruction only modify %cl we always
158	have a correct zero-extended 32-bit value in %ecx. */
159
160	L2: movb (%eax), %cl /* get byte from stopset */
161	testb %cl, %cl /* is NUL char? */
162	jz L1 /* yes => start compare loop */
163	movb %cl, (%esp,%ecx) /* set corresponding byte in stopset table */
164
165	movb 1(%eax), %cl /* get byte from stopset */
166	testb $0xff, %cl /* is NUL char? */
167	jz L1 /* yes => start compare loop */
168	movb %cl, (%esp,%ecx) /* set corresponding byte in stopset table */
169
170	movb 2(%eax), %cl /* get byte from stopset */
171	testb $0xff, %cl /* is NUL char? */
172	jz L1 /* yes => start compare loop */
173	movb %cl, (%esp,%ecx) /* set corresponding byte in stopset table */
174
175	movb 3(%eax), %cl /* get byte from stopset */
176	addl $4, %eax /* increment stopset pointer */
177	movb %cl, (%esp,%ecx) /* set corresponding byte in stopset table */
178	testb $0xff, %cl /* is NUL char? */
179	jnz L2 /* no => process next dword from stopset */
180
181	L1: leal -4(%edx), %eax /* prepare loop */
182
183	/* We use a neat trick for the following loop. Normally we would
184	have to test for two termination conditions
185	1. a character in the stopset was found
186	and
187	2. the end of the string was found
76060ec0 RM	188	As a sign that the character is in the stopset we store its
76060ec0 RM	189	value in the table. The value of NUL is NUL so the loop
59dd8641 RM	190	terminates for NUL in every case. */
	191
	192	L3: addl $4, %eax /* adjust pointer for full loop round */
	193
	194	movb (%eax), %cl /* get byte from string */
	195	testb %cl, (%esp,%ecx) /* is it contained in stopset? */
	196	jz L4 /* no => start of token */
	197
	198	movb 1(%eax), %cl /* get byte from string */
	199	testb %cl, (%esp,%ecx) /* is it contained in stopset? */
	200	jz L5 /* no => start of token */
	201
	202	movb 2(%eax), %cl /* get byte from string */
	203	testb %cl, (%esp,%ecx) /* is it contained in stopset? */
	204	jz L6 /* no => start of token */
	205
	206	movb 3(%eax), %cl /* get byte from string */
	207	testb %cl, (%esp,%ecx) /* is it contained in stopset? */
	208	jnz L3 /* yes => start of loop */
	209
	210	incl %eax /* adjust pointer */
	211	L6: incl %eax
	212	L5: incl %eax
	213
	214	/* Now we have to terminate the string. */
	215
	216	L4: leal -4(%eax), %edx /* We use %EDX for the next run. */
	217
	218	L7: addl $4, %edx /* adjust pointer for full loop round */
	219
	220	movb (%edx), %cl /* get byte from string */
	221	cmpb %cl, (%esp,%ecx) /* is it contained in skipset? */
	222	je L8 /* yes => return */
	223
	224	movb 1(%edx), %cl /* get byte from string */
	225	cmpb %cl, (%esp,%ecx) /* is it contained in skipset? */
	226	je L9 /* yes => return */
	227
	228	movb 2(%edx), %cl /* get byte from string */
	229	cmpb %cl, (%esp,%ecx) /* is it contained in skipset? */
	230	je L10 /* yes => return */
	231
	232	movb 3(%edx), %cl /* get byte from string */
	233	cmpb %cl, (%esp,%ecx) /* is it contained in skipset? */
	234	jne L7 /* no => start loop again */
	235
	236	incl %edx /* adjust pointer */
	237	L10: incl %edx
	238	L9: incl %edx
	239
	240	L8: /* Remove the stopset table. */
	241	addl $256, %esp
	242
	243	cmpl %eax, %edx
	244	je LreturnNULL /* There was no token anymore. */
	245
	246	movb $0, (%edx) /* Terminate string. */
	247
	248	/* Are we at end of string? */
	249	cmpb $0, %cl
	250	je L11
	251
	252	incl %edx
	253	L11:
254
255	/* Store the pointer to the next character. */
256	#ifdef USE_AS_STRTOK_R
257	movl 12(%esp), %ecx
258	movl %edx, (%ecx)
59dd8641 RM	259	#else
	260	# ifndef PIC
	261	movl %edx, save_ptr
	262	# else
	263	movl %edx, save_ptr@GOTOFF(%ebx)
	264	popl %ebx
	265	# endif
	266	#endif
	267	ret
	268
	269	LreturnNULL:
	270	xorl %eax, %eax
	271
ffee1316	272	/* Store current pointer for next round. */
59dd8641 RM	273	#ifdef USE_AS_STRTOK_R
59dd8641 RM	274	movl 12(%esp), %ecx
ffee1316	275	movl %edx, (%ecx)
59dd8641 RM	276	#else
59dd8641 RM	277	# ifndef PIC
ffee1316	278	movl %edx, save_ptr
59dd8641	279	# else
ffee1316	280	movl %edx, save_ptr@GOTOFF(%ebx)
59dd8641 RM	281	popl %ebx
	282	# endif
	283	#endif
	284	ret
cccda09f	285	PSEUDO_END (FUNCTION)