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      1 /*
      2  * Copyright (c) 2010-2011, The Linux Foundation. All rights reserved.
      3  *
      4  *
      5  * This program is free software; you can redistribute it and/or modify
      6  * it under the terms of the GNU General Public License version 2 and
      7  * only version 2 as published by the Free Software Foundation.
      8  *
      9  * This program is distributed in the hope that it will be useful,
     10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
     11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     12  * GNU General Public License for more details.
     13  *
     14  * You should have received a copy of the GNU General Public License
     15  * along with this program; if not, write to the Free Software
     16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
     17  * 02110-1301, USA.
     18  */
     19 
     20 /*
     21  * Description
     22  *
     23  *   library function for memcpy where length bytes are copied from
     24  *   ptr_in to ptr_out. ptr_out is returned unchanged.
     25  *   Allows any combination of alignment on input and output pointers
     26  *   and length from 0 to 2^32-1
     27  *
     28  * Restrictions
     29  *   The arrays should not overlap, the program will produce undefined output
     30  *   if they do.
     31  *   For blocks less than 16 bytes a byte by byte copy is performed. For
     32  *   8byte alignments, and length multiples, a dword copy is performed up to
     33  *   96bytes
     34  * History
     35  *
     36  *   DJH  5/15/09 Initial version 1.0
     37  *   DJH  6/ 1/09 Version 1.1 modified ABI to inlcude R16-R19
     38  *   DJH  7/12/09 Version 1.2 optimized codesize down to 760 was 840
     39  *   DJH 10/14/09 Version 1.3 added special loop for aligned case, was
     40  *                            overreading bloated codesize back up to 892
     41  *   DJH  4/20/10 Version 1.4 fixed Ldword_loop_epilog loop to prevent loads
     42  *                            occuring if only 1 left outstanding, fixes bug
     43  *                            # 3888, corrected for all alignments. Peeled off
     44  *                            1 32byte chunk from kernel loop and extended 8byte
     45  *                            loop at end to solve all combinations and prevent
     46  *                            over read.  Fixed Ldword_loop_prolog to prevent
     47  *                            overread for blocks less than 48bytes. Reduced
     48  *                            codesize to 752 bytes
     49  *   DJH  4/21/10 version 1.5 1.4 fix broke code for input block ends not
     50  *                            aligned to dword boundaries,underwriting by 1
     51  *                            byte, added detection for this and fixed. A
     52  *                            little bloat.
     53  *   DJH  4/23/10 version 1.6 corrected stack error, R20 was not being restored
     54  *                            always, fixed the error of R20 being modified
     55  *                            before it was being saved
     56  * Natural c model
     57  * ===============
     58  * void * memcpy(char * ptr_out, char * ptr_in, int length) {
     59  *   int i;
     60  *   if(length) for(i=0; i < length; i++) { ptr_out[i] = ptr_in[i]; }
     61  *   return(ptr_out);
     62  * }
     63  *
     64  * Optimized memcpy function
     65  * =========================
     66  * void * memcpy(char * ptr_out, char * ptr_in, int len) {
     67  *   int i, prolog, kernel, epilog, mask;
     68  *   u8 offset;
     69  *   s64 data0, dataF8, data70;
     70  *
     71  *   s64 * ptr8_in;
     72  *   s64 * ptr8_out;
     73  *   s32 * ptr4;
     74  *   s16 * ptr2;
     75  *
     76  *   offset = ((int) ptr_in) & 7;
     77  *   ptr8_in = (s64 *) &ptr_in[-offset];   //read in the aligned pointers
     78  *
     79  *   data70 = *ptr8_in++;
     80  *   dataF8 = *ptr8_in++;
     81  *
     82  *   data0 = HEXAGON_P_valignb_PPp(dataF8, data70, offset);
     83  *
     84  *   prolog = 32 - ((int) ptr_out);
     85  *   mask  = 0x7fffffff >> HEXAGON_R_cl0_R(len);
     86  *   prolog = prolog & mask;
     87  *   kernel = len - prolog;
     88  *   epilog = kernel & 0x1F;
     89  *   kernel = kernel>>5;
     90  *
     91  *   if (prolog & 1) { ptr_out[0] = (u8) data0; data0 >>= 8; ptr_out += 1;}
     92  *   ptr2 = (s16 *) &ptr_out[0];
     93  *   if (prolog & 2) { ptr2[0] = (u16) data0;  data0 >>= 16; ptr_out += 2;}
     94  *   ptr4 = (s32 *) &ptr_out[0];
     95  *   if (prolog & 4) { ptr4[0] = (u32) data0;  data0 >>= 32; ptr_out += 4;}
     96  *
     97  *   offset = offset + (prolog & 7);
     98  *   if (offset >= 8) {
     99  *     data70 = dataF8;
    100  *     dataF8 = *ptr8_in++;
    101  *   }
    102  *   offset = offset & 0x7;
    103  *
    104  *   prolog = prolog >> 3;
    105  *   if (prolog) for (i=0; i < prolog; i++) {
    106  *       data0 = HEXAGON_P_valignb_PPp(dataF8, data70, offset);
    107  *       ptr8_out = (s64 *) &ptr_out[0]; *ptr8_out = data0; ptr_out += 8;
    108  *       data70 = dataF8;
    109  *       dataF8 = *ptr8_in++;
    110  *   }
    111  *   if(kernel) { kernel -= 1; epilog += 32; }
    112  *   if(kernel) for(i=0; i < kernel; i++) {
    113  *       data0 = HEXAGON_P_valignb_PPp(dataF8, data70, offset);
    114  *       ptr8_out = (s64 *) &ptr_out[0]; *ptr8_out = data0; ptr_out += 8;
    115  *       data70 = *ptr8_in++;
    116  *
    117  *       data0 = HEXAGON_P_valignb_PPp(data70, dataF8, offset);
    118  *       ptr8_out = (s64 *) &ptr_out[0]; *ptr8_out = data0; ptr_out += 8;
    119  *       dataF8 = *ptr8_in++;
    120  *
    121  *       data0 = HEXAGON_P_valignb_PPp(dataF8, data70, offset);
    122  *       ptr8_out = (s64 *) &ptr_out[0]; *ptr8_out = data0; ptr_out += 8;
    123  *       data70 = *ptr8_in++;
    124  *
    125  *       data0 = HEXAGON_P_valignb_PPp(data70, dataF8, offset);
    126  *       ptr8_out = (s64 *) &ptr_out[0]; *ptr8_out = data0; ptr_out += 8;
    127  *       dataF8 = *ptr8_in++;
    128  *   }
    129  *   epilogdws = epilog >> 3;
    130  *   if (epilogdws) for (i=0; i < epilogdws; i++) {
    131  *       data0 = HEXAGON_P_valignb_PPp(dataF8, data70, offset);
    132  *       ptr8_out = (s64 *) &ptr_out[0]; *ptr8_out = data0; ptr_out += 8;
    133  *       data70 = dataF8;
    134  *       dataF8 = *ptr8_in++;
    135  *   }
    136  *   data0 = HEXAGON_P_valignb_PPp(dataF8, data70, offset);
    137  *
    138  *   ptr4 = (s32 *) &ptr_out[0];
    139  *   if (epilog & 4) { ptr4[0] = (u32) data0; data0 >>= 32; ptr_out += 4;}
    140  *   ptr2 = (s16 *) &ptr_out[0];
    141  *   if (epilog & 2) { ptr2[0] = (u16) data0; data0 >>= 16; ptr_out += 2;}
    142  *   if (epilog & 1) { *ptr_out++ = (u8) data0; }
    143  *
    144  *   return(ptr_out - length);
    145  * }
    146  *
    147  * Codesize : 784 bytes
    148  */
    149 
    150 
    151 #define ptr_out		R0	/*  destination  pounter  */
    152 #define ptr_in		R1	/*  source pointer  */
    153 #define len		R2	/*  length of copy in bytes  */
    154 
    155 #define data70		R13:12	/*  lo 8 bytes of non-aligned transfer  */
    156 #define dataF8		R11:10	/*  hi 8 bytes of non-aligned transfer  */
    157 #define ldata0		R7:6	/*  even 8 bytes chunks  */
    158 #define ldata1		R25:24	/*  odd 8 bytes chunks  */
    159 #define data1		R7	/*  lower 8 bytes of ldata1  */
    160 #define data0		R6	/*  lower 8 bytes of ldata0  */
    161 
    162 #define ifbyte		p0	/*  if transfer has bytes in epilog/prolog  */
    163 #define ifhword		p0	/*  if transfer has shorts in epilog/prolog  */
    164 #define ifword		p0	/*  if transfer has words in epilog/prolog  */
    165 #define noprolog	p0	/*  no prolog, xfer starts at 32byte  */
    166 #define nokernel	p1	/*  no 32byte multiple block in the transfer  */
    167 #define noepilog	p0	/*  no epilog, xfer ends on 32byte boundary  */
    168 #define align		p2	/*  alignment of input rel to 8byte boundary  */
    169 #define kernel1		p0	/*  kernel count == 1  */
    170 
    171 #define dalign		R25	/*  rel alignment of input to output data  */
    172 #define star3		R16	/*  number bytes in prolog - dwords  */
    173 #define rest		R8	/*  length - prolog bytes  */
    174 #define back		R7	/*  nr bytes > dword boundary in src block  */
    175 #define epilog		R3	/*  bytes in epilog  */
    176 #define inc		R15:14	/*  inc kernel by -1 and defetch ptr by 32  */
    177 #define kernel		R4	/*  number of 32byte chunks in kernel  */
    178 #define ptr_in_p_128	R5	/*  pointer for prefetch of input data  */
    179 #define mask		R8	/*  mask used to determine prolog size  */
    180 #define shift		R8	/*  used to work a shifter to extract bytes  */
    181 #define shift2		R5	/*  in epilog to workshifter to extract bytes */
    182 #define prolog		R15	/*  bytes in  prolog  */
    183 #define epilogdws	R15	/*  number dwords in epilog  */
    184 #define shiftb		R14	/*  used to extract bytes  */
    185 #define offset		R9	/*  same as align in reg  */
    186 #define ptr_out_p_32	R17	/*  pointer to output dczero  */
    187 #define align888	R14	/*  if simple dword loop can be used  */
    188 #define len8		R9	/*  number of dwords in length  */
    189 #define over		R20	/*  nr of bytes > last inp buf dword boundary */
    190 
    191 #define ptr_in_p_128kernel	R5:4	/*  packed fetch pointer & kernel cnt */
    192 
    193 	.section .text
    194 	.p2align 4
    195         .global memcpy
    196         .type memcpy, @function
    197 memcpy:
    198 {
    199 	p2 = cmp.eq(len, #0);		/*  =0 */
    200 	align888 = or(ptr_in, ptr_out);	/*  %8 < 97 */
    201 	p0 = cmp.gtu(len, #23);		/*  %1, <24 */
    202 	p1 = cmp.eq(ptr_in, ptr_out);	/*  attempt to overwrite self */
    203 }
    204 {
    205 	p1 = or(p2, p1);
    206 	p3 = cmp.gtu(len, #95);		/*  %8 < 97 */
    207 	align888 = or(align888, len);	/*  %8 < 97 */
    208 	len8 = lsr(len, #3);		/*  %8 < 97 */
    209 }
    210 {
    211 	dcfetch(ptr_in);		/*  zero/ptrin=ptrout causes fetch */
    212 	p2 = bitsclr(align888, #7);	/*  %8 < 97  */
    213 	if(p1) jumpr r31;		/*  =0  */
    214 }
    215 {
    216 	p2 = and(p2,!p3);			/*  %8 < 97  */
    217 	if (p2.new) len = add(len, #-8);	/*  %8 < 97  */
    218 	if (p2.new) jump:NT .Ldwordaligned; 	/*  %8 < 97  */
    219 }
    220 {
    221 	if(!p0) jump .Lbytes23orless;	/*  %1, <24  */
    222 	mask.l = #LO(0x7fffffff);
    223 	/*  all bytes before line multiples of data  */
    224 	prolog = sub(#0, ptr_out);
    225 }
    226 {
    227 	/*  save r31 on stack, decrement sp by 16  */
    228 	allocframe(#24);
    229 	mask.h = #HI(0x7fffffff);
    230 	ptr_in_p_128 = add(ptr_in, #32);
    231 	back = cl0(len);
    232 }
    233 {
    234 	memd(sp+#0) = R17:16;		/*  save r16,r17 on stack6  */
    235 	r31.l = #LO(.Lmemcpy_return);	/*  set up final return pointer  */
    236 	prolog &= lsr(mask, back);
    237 	offset = and(ptr_in, #7);
    238 }
    239 {
    240 	memd(sp+#8) = R25:24;		/*  save r25,r24 on stack  */
    241 	dalign = sub(ptr_out, ptr_in);
    242 	r31.h = #HI(.Lmemcpy_return);	/*  set up final return pointer  */
    243 }
    244 {
    245 	/*  see if there if input buffer end if aligned  */
    246 	over = add(len, ptr_in);
    247 	back = add(len, offset);
    248 	memd(sp+#16) = R21:20;		/*  save r20,r21 on stack  */
    249 }
    250 {
    251 	noprolog = bitsclr(prolog, #7);
    252 	prolog = and(prolog, #31);
    253 	dcfetch(ptr_in_p_128);
    254 	ptr_in_p_128 = add(ptr_in_p_128, #32);
    255 }
    256 {
    257 	kernel = sub(len, prolog);
    258 	shift = asl(prolog, #3);
    259 	star3 = and(prolog, #7);
    260 	ptr_in = and(ptr_in, #-8);
    261 }
    262 {
    263 	prolog = lsr(prolog, #3);
    264 	epilog = and(kernel, #31);
    265 	ptr_out_p_32 = add(ptr_out, prolog);
    266 	over = and(over, #7);
    267 }
    268 {
    269 	p3 = cmp.gtu(back, #8);
    270 	kernel = lsr(kernel, #5);
    271 	dcfetch(ptr_in_p_128);
    272 	ptr_in_p_128 = add(ptr_in_p_128, #32);
    273 }
    274 {
    275 	p1 = cmp.eq(prolog, #0);
    276 	if(!p1.new) prolog = add(prolog, #1);
    277 	dcfetch(ptr_in_p_128);	/*  reserve the line 64bytes on  */
    278 	ptr_in_p_128 = add(ptr_in_p_128, #32);
    279 }
    280 {
    281 	nokernel = cmp.eq(kernel,#0);
    282 	dcfetch(ptr_in_p_128);	/* reserve the line 64bytes on  */
    283 	ptr_in_p_128 = add(ptr_in_p_128, #32);
    284 	shiftb = and(shift, #8);
    285 }
    286 {
    287 	dcfetch(ptr_in_p_128);		/*  reserve the line 64bytes on  */
    288 	ptr_in_p_128 = add(ptr_in_p_128, #32);
    289 	if(nokernel) jump .Lskip64;
    290 	p2 = cmp.eq(kernel, #1);	/*  skip ovr if kernel == 0  */
    291 }
    292 {
    293 	dczeroa(ptr_out_p_32);
    294 	/*  don't advance pointer  */
    295 	if(!p2) ptr_out_p_32 = add(ptr_out_p_32, #32);
    296 }
    297 {
    298 	dalign = and(dalign, #31);
    299 	dczeroa(ptr_out_p_32);
    300 }
    301 .Lskip64:
    302 {
    303 	data70 = memd(ptr_in++#16);
    304 	if(p3) dataF8 = memd(ptr_in+#8);
    305 	if(noprolog) jump .Lnoprolog32;
    306 	align = offset;
    307 }
    308 /*  upto initial 7 bytes  */
    309 {
    310 	ldata0 = valignb(dataF8, data70, align);
    311 	ifbyte = tstbit(shift,#3);
    312 	offset = add(offset, star3);
    313 }
    314 {
    315 	if(ifbyte) memb(ptr_out++#1) = data0;
    316 	ldata0 = lsr(ldata0, shiftb);
    317 	shiftb = and(shift, #16);
    318 	ifhword = tstbit(shift,#4);
    319 }
    320 {
    321 	if(ifhword) memh(ptr_out++#2) = data0;
    322 	ldata0 = lsr(ldata0, shiftb);
    323 	ifword = tstbit(shift,#5);
    324 	p2 = cmp.gtu(offset, #7);
    325 }
    326 {
    327 	if(ifword) memw(ptr_out++#4) = data0;
    328 	if(p2) data70 = dataF8;
    329 	if(p2) dataF8 = memd(ptr_in++#8);	/*  another 8 bytes  */
    330 	align = offset;
    331 }
    332 .Lnoprolog32:
    333 {
    334 	p3 = sp1loop0(.Ldword_loop_prolog, prolog)
    335 	rest = sub(len, star3);	/*  whats left after the loop  */
    336 	p0 = cmp.gt(over, #0);
    337 }
    338 	if(p0) rest = add(rest, #16);
    339 .Ldword_loop_prolog:
    340 {
    341 	if(p3) memd(ptr_out++#8) = ldata0;
    342 	ldata0 = valignb(dataF8, data70, align);
    343 	p0 = cmp.gt(rest, #16);
    344 }
    345 {
    346 	data70 = dataF8;
    347 	if(p0) dataF8 = memd(ptr_in++#8);
    348 	rest = add(rest, #-8);
    349 }:endloop0
    350 .Lkernel:
    351 {
    352 	/*  kernel is at least 32bytes  */
    353 	p3 = cmp.gtu(kernel, #0);
    354 	/*  last itn. remove edge effects  */
    355 	if(p3.new) kernel = add(kernel, #-1);
    356 	/*  dealt with in last dword loop  */
    357 	if(p3.new) epilog = add(epilog, #32);
    358 }
    359 {
    360 	nokernel = cmp.eq(kernel, #0);		/*  after adjustment, recheck */
    361 	if(nokernel.new) jump:NT .Lepilog;	/*  likely not taken  */
    362 	inc = combine(#32, #-1);
    363 	p3 = cmp.gtu(dalign, #24);
    364 }
    365 {
    366 	if(p3) jump .Lodd_alignment;
    367 }
    368 {
    369 	loop0(.Loword_loop_25to31, kernel);
    370 	kernel1 = cmp.gtu(kernel, #1);
    371 	rest = kernel;
    372 }
    373 	.falign
    374 .Loword_loop_25to31:
    375 {
    376 	dcfetch(ptr_in_p_128);	/*  prefetch 4 lines ahead  */
    377 	if(kernel1) ptr_out_p_32 = add(ptr_out_p_32, #32);
    378 }
    379 {
    380 	dczeroa(ptr_out_p_32);	/*  reserve the next 32bytes in cache  */
    381 	p3 = cmp.eq(kernel, rest);
    382 }
    383 {
    384 	/*  kernel -= 1  */
    385 	ptr_in_p_128kernel = vaddw(ptr_in_p_128kernel, inc);
    386 	/*  kill write on first iteration  */
    387 	if(!p3) memd(ptr_out++#8) = ldata1;
    388 	ldata1 = valignb(dataF8, data70, align);
    389 	data70 = memd(ptr_in++#8);
    390 }
    391 {
    392 	memd(ptr_out++#8) = ldata0;
    393 	ldata0 = valignb(data70, dataF8, align);
    394 	dataF8 = memd(ptr_in++#8);
    395 }
    396 {
    397 	memd(ptr_out++#8) = ldata1;
    398 	ldata1 = valignb(dataF8, data70, align);
    399 	data70 = memd(ptr_in++#8);
    400 }
    401 {
    402 	memd(ptr_out++#8) = ldata0;
    403 	ldata0 = valignb(data70, dataF8, align);
    404 	dataF8 = memd(ptr_in++#8);
    405 	kernel1 = cmp.gtu(kernel, #1);
    406 }:endloop0
    407 {
    408 	memd(ptr_out++#8) = ldata1;
    409 	jump .Lepilog;
    410 }
    411 .Lodd_alignment:
    412 {
    413 	loop0(.Loword_loop_00to24, kernel);
    414 	kernel1 = cmp.gtu(kernel, #1);
    415 	rest = add(kernel, #-1);
    416 }
    417 	.falign
    418 .Loword_loop_00to24:
    419 {
    420 	dcfetch(ptr_in_p_128);	/*  prefetch 4 lines ahead  */
    421 	ptr_in_p_128kernel = vaddw(ptr_in_p_128kernel, inc);
    422 	if(kernel1) ptr_out_p_32 = add(ptr_out_p_32, #32);
    423 }
    424 {
    425 	dczeroa(ptr_out_p_32);	/*  reserve the next 32bytes in cache  */
    426 }
    427 {
    428 	memd(ptr_out++#8) = ldata0;
    429 	ldata0 = valignb(dataF8, data70, align);
    430 	data70 = memd(ptr_in++#8);
    431 }
    432 {
    433 	memd(ptr_out++#8) = ldata0;
    434 	ldata0 = valignb(data70, dataF8, align);
    435 	dataF8 = memd(ptr_in++#8);
    436 }
    437 {
    438 	memd(ptr_out++#8) = ldata0;
    439 	ldata0 = valignb(dataF8, data70, align);
    440 	data70 = memd(ptr_in++#8);
    441 }
    442 {
    443 	memd(ptr_out++#8) = ldata0;
    444 	ldata0 = valignb(data70, dataF8, align);
    445 	dataF8 = memd(ptr_in++#8);
    446 	kernel1 = cmp.gtu(kernel, #1);
    447 }:endloop0
    448 .Lepilog:
    449 {
    450 	noepilog = cmp.eq(epilog,#0);
    451 	epilogdws = lsr(epilog, #3);
    452 	kernel = and(epilog, #7);
    453 }
    454 {
    455 	if(noepilog) jumpr r31;
    456 	if(noepilog) ptr_out = sub(ptr_out, len);
    457 	p3 = cmp.eq(epilogdws, #0);
    458 	shift2 = asl(epilog, #3);
    459 }
    460 {
    461 	shiftb = and(shift2, #32);
    462 	ifword = tstbit(epilog,#2);
    463 	if(p3) jump .Lepilog60;
    464 	if(!p3) epilog = add(epilog, #-16);
    465 }
    466 {
    467 	loop0(.Ldword_loop_epilog, epilogdws);
    468 	/*  stop criteria is lsbs unless = 0 then its 8  */
    469 	p3 = cmp.eq(kernel, #0);
    470 	if(p3.new) kernel= #8;
    471 	p1 = cmp.gt(over, #0);
    472 }
    473 	/*  if not aligned to end of buffer execute 1 more iteration  */
    474 	if(p1) kernel= #0;
    475 .Ldword_loop_epilog:
    476 {
    477 	memd(ptr_out++#8) = ldata0;
    478 	ldata0 = valignb(dataF8, data70, align);
    479 	p3 = cmp.gt(epilog, kernel);
    480 }
    481 {
    482 	data70 = dataF8;
    483 	if(p3) dataF8 = memd(ptr_in++#8);
    484 	epilog = add(epilog, #-8);
    485 }:endloop0
    486 /* copy last 7 bytes */
    487 .Lepilog60:
    488 {
    489 	if(ifword) memw(ptr_out++#4) = data0;
    490 	ldata0 = lsr(ldata0, shiftb);
    491 	ifhword = tstbit(epilog,#1);
    492 	shiftb = and(shift2, #16);
    493 }
    494 {
    495 	if(ifhword) memh(ptr_out++#2) = data0;
    496 	ldata0 = lsr(ldata0, shiftb);
    497 	ifbyte = tstbit(epilog,#0);
    498 	if(ifbyte.new) len = add(len, #-1);
    499 }
    500 {
    501 	if(ifbyte) memb(ptr_out) = data0;
    502 	ptr_out = sub(ptr_out, len);	/*  return dest pointer  */
    503         jumpr r31;
    504 }
    505 /*  do byte copy for small n  */
    506 .Lbytes23orless:
    507 {
    508 	p3 = sp1loop0(.Lbyte_copy, len);
    509 	len = add(len, #-1);
    510 }
    511 .Lbyte_copy:
    512 {
    513 	data0 = memb(ptr_in++#1);
    514 	if(p3) memb(ptr_out++#1) = data0;
    515 }:endloop0
    516 {
    517 	memb(ptr_out) = data0;
    518 	ptr_out = sub(ptr_out, len);
    519 	jumpr r31;
    520 }
    521 /*  do dword copies for aligned in, out and length  */
    522 .Ldwordaligned:
    523 {
    524 	p3 = sp1loop0(.Ldword_copy, len8);
    525 }
    526 .Ldword_copy:
    527 {
    528 	if(p3) memd(ptr_out++#8) = ldata0;
    529 	ldata0 = memd(ptr_in++#8);
    530 }:endloop0
    531 {
    532 	memd(ptr_out) = ldata0;
    533 	ptr_out = sub(ptr_out, len);
    534 	jumpr r31;	/*  return to function caller  */
    535 }
    536 .Lmemcpy_return:
    537 	r21:20 = memd(sp+#16);	/*  restore r20+r21  */
    538 {
    539 	r25:24 = memd(sp+#8);	/*  restore r24+r25  */
    540 	r17:16 = memd(sp+#0);	/*  restore r16+r17  */
    541 }
    542 	deallocframe;	/*  restore r31 and incrment stack by 16  */
    543 	jumpr r31
    544