1/* Vector optimized 32/64 bit S/390 version of wcspbrk.
2   Copyright (C) 2015-2021 Free Software Foundation, Inc.
3   This file is part of the GNU C Library.
4
5   The GNU C Library is free software; you can redistribute it and/or
6   modify it under the terms of the GNU Lesser General Public
7   License as published by the Free Software Foundation; either
8   version 2.1 of the License, or (at your option) any later version.
9
10   The GNU C Library is distributed in the hope that it will be useful,
11   but WITHOUT ANY WARRANTY; without even the implied warranty of
12   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13   Lesser General Public License for more details.
14
15   You should have received a copy of the GNU Lesser General Public
16   License along with the GNU C Library; if not, see
17   <https://www.gnu.org/licenses/>.  */
18
19#include <ifunc-wcspbrk.h>
20#if HAVE_WCSPBRK_Z13
21
22# include "sysdep.h"
23# include "asm-syntax.h"
24
25	.text
26
27/* wchar_t *wcspbrk (const wchar_t *s, const wchar_t * accept)
28   The  wcspbrk()  function locates the first occurrence in the string s
29   of any of the characters in the string accept and returns a pointer
30   to that character or NULL if not found.
31
32   This method checks the length of accept string. If it fits entirely
33   in one vector register, a fast algorithm is used, which does not need
34   to check multiple parts of accept-string. Otherwise a slower full
35   check of accept-string is used.
36
37   register overview:
38   r3:  pointer to start of accept-string
39   r2:  pointer to start of search-string
40   r0:  loaded byte count of vlbb search-string (32bit unsigned)
41   r4:  found byte index (32bit unsigned)
42   r1:  current return len (64bit unsigned)
43   v16: search-string
44   v17: accept-string
45   v18: temp-vreg
46
47   ONLY FOR SLOW:
48   v19: first accept-string
49   v20: zero for preparing acc-vector
50   v21: global mask; 1 indicates a match between
51	search-string-vreg and any accept-character
52   v22: current mask; 1 indicates a match between
53	search-string-vreg and any accept-character in current acc-vreg
54   v24: one for result-checking of former string-part
55   v30, v31: for re-/storing registers r6, r8, r9
56   r5:  current len of accept-string
57   r6:  zero-index in search-string or 16 if no zero
58	or min(zero-index, loaded byte count)
59   r8:  >0, if former accept-string-part contains a zero,
60	otherwise =0;
61   r9:  loaded byte count of vlbb accept-string
62*/
63ENTRY(WCSPBRK_Z13)
64	.machine "z13"
65	.machinemode "zarch_nohighgprs"
66
67	tmll	%r2,3		/* Test if s is 4-byte aligned?  */
68	jne	.Lfallback	/* And use common-code variant if not.  */
69
70	/*
71	  Check if accept-string fits in one vreg:
72	  ----------------------------------------
73	*/
74	vlbb	%v17,0(%r3),6	/* Load accept.  */
75	lcbb	%r0,0(%r3),6
76	jo	.Lcheck_onbb	/* Special case if accept lays
77				   on block-boundary.  */
78
79.Lcheck_notonbb:
80	lghi	%r1,0		/* Zero out current len.  */
81	vlgvf	%r0,%v17,0	/* Get first element.  */
82	clije	%r0,0,.Lfast_end_null /* Return null if accept is empty.  */
83
84	vistrfs	%v17,%v17	/* Fill with zeros after first zero.  */
85	je	.Lfast		/* Zero found -> accept fits in one vreg.  */
86	j	.Lslow		/* No zero -> accept exceeds one vreg  */
87
88
89.Lcheck_onbb:
90	/* Accept lays on block-boundary.  */
91	nill	%r0,65532	/* Recognize only fully loaded characters.  */
92	je	.Lcheck_onbb2	/* Reload vr, if we loaded no full wchar_t.  */
93	vfenezf	%v18,%v17,%v17	/* Search zero in loaded accept bytes.  */
94	vlgvb	%r4,%v18,7	/* Get index of zero or 16 if not found.  */
95	clrjl	%r4,%r0,.Lcheck_notonbb /* Zero index < loaded bytes count ->
96					    accept fits in one vreg;
97					    Fill with zeros and proceed
98					    with FAST.  */
99.Lcheck_onbb2:
100	vl	%v17,0(%r3)	/* Load accept, which exceeds loaded bytes.  */
101	j	.Lcheck_notonbb /* Check if accept fits in one vreg.  */
102
103
104	/*
105	  Search s for accept in one vreg
106	  -------------------------------
107	*/
108.Lfast:
109	/* Complete accept-string in v17 and remaining bytes are zero.  */
110
111	vlbb	%v16,0(%r2),6	/* Load s until next 4k-byte boundary.  */
112	lcbb	%r0,0(%r2),6	/* Get bytes to 4k-byte boundary or 16.  */
113
114	vfaezfs	%v18,%v16,%v17,0 /* Find first element in v16 unequal to any
115				    in v17 or first zero element.  */
116	vlgvb	%r4,%v18,7	/* Load byte index of found element.  */
117	/* If found index is within loaded bytes, return with found
118	   element index (=equal count).  */
119	clrjl	%r4,%r0,.Lfast_loop_found2
120
121	/* Align s to 16 byte.  */
122	risbgn	%r4,%r2,60,128+63,0 /* %r3 = bits 60-63 of %r2 'and' 15.  */
123	lghi	%r1,16		/* current_len = 16.  */
124	slr	%r1,%r4		/* Compute bytes to 16bytes boundary.  */
125
126.Lfast_loop:
127	vl	%v16,0(%r1,%r2)	/* Load search-string.  */
128	vfaezfs	%v18,%v16,%v17,0 /* Find first element in v16 equal to any
129				    in v17 or first zero element.  */
130	jno	.Lfast_loop_found
131
132	vl	%v16,16(%r1,%r2)
133	vfaezfs	%v18,%v16,%v17,0
134	jno	.Lfast_loop_found16
135
136	vl	%v16,32(%r1,%r2)
137	vfaezfs	%v18,%v16,%v17,0
138	jno	.Lfast_loop_found32
139
140	vl	%v16,48(%r1,%r2)
141	vfaezfs	%v18,%v16,%v17,0
142	jno	.Lfast_loop_found48
143
144	aghi	%r1,64
145	j	.Lfast_loop	/* Loop if no element was unequal to accept
146				   and not zero.  */
147
148	/* Found equal or zero element.  */
149.Lfast_loop_found48:
150	aghi	%r1,16
151.Lfast_loop_found32:
152	aghi	%r1,16
153.Lfast_loop_found16:
154	aghi	%r1,16
155.Lfast_loop_found:
156	vlgvb	%r4,%v18,7	/* Load byte index of found element.  */
157.Lfast_loop_found2:
158	srlg	%r5,%r4,2	/* Convert byte-index to character-index.  */
159	vlgvf	%r0,%v16,0(%r5)	/* Get found element.  */
160	clije	%r0,0,.Lfast_end_null /* Return null if no accept-char found */
161	algfr	%r1,%r4		/* Add found index of char to current len.  */
162	la	%r2,0(%r1,%r2)	/* And return pointer to first equal char.  */
163	br	%r14
164
165.Lfast_end_null:
166	lghi	%r2,0		/* Return null if no character is equal.  */
167	br	%r14
168
169
170
171
172	/*
173	  Search s for accept in multiple vregs
174	  -------------------------------------
175	*/
176.Lslow:
177	/* Save registers.  */
178	vlvgg	%v30,%r6,0
179	vlvgp	%v31,%r8,%r9
180
181	/* Accept in v17 without zero */
182	vlr	%v19,%v17	/* Save first acc-part for a fast reload.  */
183	vzero	%v20		/* Zero for preparing acc-vector.  */
184	vone	%v24		/* One for checking result of former string.  */
185
186	/* Align s to 16 byte.  */
187	risbg	%r4,%r2,60,128+63,0 /* Test if s is aligned and
188				       %r4 = bits 60-63 'and' 15.  */
189	je	.Lslow_loop_str /* If s is aligned, loop aligned.  */
190	lghi	%r0,15
191	slr	%r0,%r4		/* Compute highest index to load (15-x).  */
192	vll	%v16,%r0,0(%r2) /* Load up to 16byte boundary;
193				   needs highest index, left bytes are 0.  */
194	ahi	%r0,1		/* Work with loaded byte count.  */
195	vzero	%v21		/* Zero out global mask.  */
196	lghi	%r5,0		/* Set current len of accept-string to zero.  */
197	vfenezf	%v18,%v16,%v16	/* Find zero in current string-part.  */
198	lghi	%r8,0		/* There is no zero in first accept-part.  */
199	vlgvb	%r6,%v18,7	/* Load byte index of zero or 16 if no zero.  */
200	clije	%r6,0,.Lslow_end_null /* If first element is zero
201					  (end of string) -> return null */
202	clr	%r0,%r6		/* cc==1 if loaded byte count < zero-index.  */
203	locrl	%r6,%r0		/* Load on cc==1; zero-index = lbc.  */
204	j	.Lslow_loop_acc
205
206
207	/* Process s in 16byte aligned loop.  */
208.Lslow_next_str:
209	/* Check results of former processed str-part.  */
210	vfeef	%v18,%v21,%v24	/* Find first equal match in global mask
211				   (ones in element).  */
212	vlgvb	%r4,%v18,7	/* Get index of first one (=equal)
213				   or 16 if no match.  */
214	/* Equal-index < min(zero-index, loaded byte count)
215	   -> return pointer to equal element.  */
216	clrjl	%r4,%r6,.Lslow_index_found
217	/* Zero-index < loaded byte count
218	   -> former str-part was last str-part
219	   -> return null */
220	clrjl	%r6,%r0,.Lslow_end_null
221	/* All elements are zero (=no match) -> proceed with next str-part.  */
222
223	vlr	%v17,%v19	/* Load first part of accept (no zero).  */
224	algfr	%r1,%r0		/* Add loaded byte count to current len.  */
225
226.Lslow_loop_str:
227	vl	%v16,0(%r1,%r2)	/* Load search-string */
228	lghi	%r0,16		/* Loaded byte count is 16.  */
229	vzero	%v21		/* Zero out global mask.  */
230	lghi	%r5,0		/* Set current len of accept to zero.  */
231	vfenezf	%v18,%v16,%v16	/* Find zero in current string-part.  */
232	lghi	%r8,0		/* There is no zero in first accept-part.  */
233	vlgvb	%r6,%v18,7	/* Load byte index of zero or 16 if no zero.  */
234	clije	%r6,0,.Lslow_end_null /* If first element is zero
235					  (end of string) -> return null.  */
236
237.Lslow_loop_acc:
238	vfaef	%v22,%v16,%v17,4 /* Create matching-mask (1 in mask ->
239				    Character matches any accepted character in
240				    this accept-string-part) IN=0, RT=1.  */
241	vlgvf	%r4,%v22,0	/* Get result of first element.  */
242	/* First element is equal to any accepted characters
243	   (all other parts of accept cannot lead to a match before this one)
244	   -> current len is pointing to first element
245	   -> return found */
246	clijh	%r4,0,.Lslow_end_found
247	vo	%v21,%v21,%v22	/* Global-mask = global-|matching-mask.  */
248	/* Proceed with next acc until end of acc is reached.  */
249
250
251.Lslow_next_acc:
252	clijh	%r8,0,.Lslow_next_str /* There was a zero in the last acc-part
253					  -> add index to current len and
254					     end.  */
255	vlbb	%v17,16(%r5,%r3),6 /* Load next accept part.  */
256	aghi	%r5,16		/* Increment current len of accept-string.  */
257	lcbb	%r9,0(%r5,%r3),6 /* Get loaded byte count of accept-string.  */
258	jo	.Lslow_next_acc_onbb /* Jump away ifaccept-string is
259					 on block-boundary.  */
260.Lslow_next_acc_notonbb:
261	vistrfs	%v17,%v17	/* Fill with zeros after first zero.  */
262	jo	.Lslow_loop_acc /* No zero found -> no preparation needed.  */
263
264.Lslow_next_acc_prepare_zero:
265	/* Zero in accept-part: fill zeros with first-accept-character.  */
266	vlgvf	%r8,%v17,0	/* Load first element of acc-part.  */
267	clije	%r8,0,.Lslow_next_str /* Proceed with next string-part,
268					  If first char in this part of accept
269					  is a zero.  */
270	/* r8>0 -> zero found in this acc-part.  */
271	vrepf	%v18,%v17,0	/* Replicate first char accross all chars.  */
272	vceqf	%v22,%v20,%v17	/* Create a mask (v22) of null chars
273				   by comparing with 0 (v20).  */
274	vsel	%v17,%v18,%v17,%v22 /* Replace null chars with first char.  */
275	j	.Lslow_loop_acc /* Accept part is prepared -> process.  */
276
277.Lslow_next_acc_onbb:
278	nill	%r9,65532	/* Recognize only fully loaded characters.  */
279	je	.Lslow_next_acc_onbb2 /* Reload vr, if no full wchar_t.  */
280	vfenezf	%v18,%v17,%v17	/* Find zero in loaded bytes of accept part.  */
281	vlgvb	%r8,%v18,7	/* Load byte index of zero.  */
282	clrjl	%r8,%r9,.Lslow_next_acc_notonbb /* Found a zero in loaded bytes
283						    -> Prepare vreg.  */
284.Lslow_next_acc_onbb2:
285	vl	%v17,0(%r5,%r3)	/* Load over boundary ...  */
286	lghi	%r8,0		/* r8=0 -> no zero in this part of acc,
287				   check for zero is in jump-target.  */
288	j	.Lslow_next_acc_notonbb /* ... and search for zero in
289					    fully loaded vreg again.  */
290
291.Lslow_end_null:
292	lghi	%r1,0		/* Return null if no character is equal.  */
293	j	.Lslow_end
294
295.Lslow_loop_found:
296	vlgvb	%r4,%v18,7	/* Load byte index of found element.  */
297	srlg	%r5,%r4,2	/* Convert byte-index to character-index.  */
298	vlgvf	%r0,%v16,0(%r5)	/* Get found element.  */
299	clije	%r0,0,.Lslow_end_null /* Return null if no acc-char found.  */
300
301.Lslow_index_found:
302	algfr	%r1,%r4		/* Add found index of char to current len.  */
303.Lslow_end_found:
304	la	%r1,0(%r1,%r2)	/* And return pointer to first equal char.  */
305
306.Lslow_end:
307	/* Restore registers.  */
308	vlgvg	%r6,%v30,0
309	vlgvg	%r8,%v31,0
310	vlgvg	%r9,%v31,1
311	lgr	%r2,%r1
312	br	%r14
313.Lfallback:
314	jg	WCSPBRK_C
315END(WCSPBRK_Z13)
316
317# if ! HAVE_WCSPBRK_IFUNC
318strong_alias (WCSPBRK_Z13, wcspbrk)
319# endif
320
321# if defined HAVE_S390_MIN_Z13_ZARCH_ASM_SUPPORT \
322	&& defined SHARED && IS_IN (libc)
323strong_alias (WCSPBRK_Z13, __GI_wcspbrk)
324# endif
325#endif
326