diff options
Diffstat (limited to 'newlib/libc/machine/hppa/strncpy.S')
| -rw-r--r-- | newlib/libc/machine/hppa/strncpy.S | 256 |
1 files changed, 256 insertions, 0 deletions
diff --git a/newlib/libc/machine/hppa/strncpy.S b/newlib/libc/machine/hppa/strncpy.S new file mode 100644 index 0000000..3b1503e --- /dev/null +++ b/newlib/libc/machine/hppa/strncpy.S @@ -0,0 +1,256 @@ +/* + * (c) Copyright 1986 HEWLETT-PACKARD COMPANY + * + * To anyone who acknowledges that this file is provided "AS IS" + * without any express or implied warranty: + * permission to use, copy, modify, and distribute this file + * for any purpose is hereby granted without fee, provided that + * the above copyright notice and this notice appears in all + * copies, and that the name of Hewlett-Packard Company not be + * used in advertising or publicity pertaining to distribution + * of the software without specific, written prior permission. + * Hewlett-Packard Company makes no representations about the + * suitability of this software for any purpose. + */ + +/* HPUX_ID: @(#) $Revision: 1.1 $ */ +/* + * strncpy(s1, s2, n) + * + * Copy s2 to s1, truncating or null-padding to always copy n bytes + * return s1 + */ + +#include "DEFS.h" + +#define d_addr r26 +#define s_addr r25 +#define count r24 +#define tmp1 r19 +#define tmp2 r20 +#define tmp3 r21 +#define tmp4 r22 +#define tmp5 arg3 +#define save r1 + + +ENTRY(strncpy) + + combt,= s_addr,r0,pad_null_bytes1 /* if s2==NULL then pad nulls and exit */ + copy d_addr,ret0 /* The return value is defined to be the value of d_addr. DELAY SLOT*/ + addibt,<,n -4,count,byteloop /* If count is <= 4 don't get fancy.*/ + + extru s_addr,31,2,tmp1 /* Extract the low two bits of the source address.*/ + extru d_addr,31,2,tmp5 /* Extract the low two bits of the destination address.*/ + add count,tmp5,count /* pre increment the count by the byte address so that the count is*/ + comb,<> tmp5,tmp1,not_aligned /* branch if tmp5<>tmp1. */ + dep 0,31,2,s_addr /* Compute the word address of the source. DELAY SLOT.*/ +/* aligned*/ + combt,= tmp5,r0,skip_mask + ldwm 4(0,s_addr),tmp1 /* tmp1 = *s_addr s_addr += 4 (DELAY SLOT)*/ + sh3add tmp5,r0,save /* compute mask in save*/ + mtctl save,11 + zvdepi -2,32,save + b skip_mask /* don't reload tmp1*/ + or save,tmp1,tmp1 /* or mask with data*/ + +chunks: + ldwm 4(0,s_addr),tmp1 /* get a word*/ + +skip_mask: + uxor,nbz tmp1,r0,save /* check for null*/ + b,n null1 + addibf,< -4,count,chunks + stbys,b,m tmp1,4(0,d_addr) /* store word (delay slot)*/ + +/* back_porch last word to store*/ + addibt,=,n 4,count,done /* if count = 0 we're, of course, done !*/ + ldws 0(s_addr),tmp1 /* load up the back_porch*/ + add d_addr,count,d_addr/* final store address is +1 too high !*/ + sh3add count,r0, save /* setup right mask based on count*/ + mtctl save,r11 + zvdepi -2,32,save /*save now has left-hand mask*/ + uaddcm r0,save,save /*form right hand mask */ + or tmp1,save,tmp1 /*and insert data*/ + uxor,nbz tmp1,r0,save /* check for null*/ + b,n null2 + bv 0(r2) + stbys,e tmp1,0(d_addr) /* done */ + +/* Begin non_aligned code. */ +not_aligned: + sub,>= tmp5,tmp1,tmp3 /* compute the shift amt.and skip load if tmp5 > tmp1.*/ + ldwm 4(0,s_addr),tmp1 /* load up the first word from the source. tmp1 = *s_addr++*/ + zdep tmp3,28,29,tmp4 /* compute the number of bits to shift */ + mtctl tmp4,11 /* load the shift count into cr11 = shift count register.*/ + addibt,<,n -4,count,chkchnk2 /* first step in pre adjustment of count for looping.*/ + + ldwm 4(0,s_addr),tmp2 /* get either first or second word from source. */ + combt,= tmp5,r0,skip_mask2 /* don't mask if whole word is valid*/ + vshd tmp1,tmp2,tmp3 /* position data ! (delay slot)*/ + sh3add tmp5,r0,save /* setup r1*/ + mtctl save,r11 /* setup mask in save*/ + zvdepi -2,32,save + or save, tmp3, tmp3 + mtctl tmp4,11 /* re-load the shift count into cr11 */ + b skip_mask2 + copy r0, tmp5 /* zero out tmp5 so we don't try to mask again*/ + +chunk2: + ldwm 4(0,s_addr),tmp2 + vshd tmp1,tmp2,tmp3 + +skip_mask2: + uxor,nbz tmp3, r0, save + b,n null3 + stbys,b,m tmp3,4(0,d_addr) /* store ! */ + + ldwm 4(0,s_addr),tmp1 /* get 2nd word ! */ + vshd tmp2,tmp1,tmp3 /* position data ! */ + uxor,nbz tmp3, r0, save + b,n null4 + + addibf,< -8,count,chunk2 /* If count is still >= 8 do another loop.*/ + stbys,b,m tmp3,4(0,d_addr) /* store !*/ + +chkchnk2: + addibt,<,n 4,count,bp_0 /* if we don't have 4 bytes left then do the back porch (bp_0)*/ + +subchnk2: /* we have less than 8 chars to copy*/ + + ldwm 4(0,s_addr),tmp2 /* get next word !*/ + combt,= tmp5,r0,skip_mask3 + vshd tmp1,tmp2,tmp3 /* position data !*/ + sh3add tmp5,r0,save /* setup r1*/ + mtctl save,r11 /* setup mask in save*/ + zvdepi -2,32,save + or save, tmp3, tmp3 + mtctl tmp4,11 /* restore shift value again */ + copy r0, tmp5 /* zero out tmp5 so we don't try to mask again*/ +skip_mask3: + uxor,nbz tmp3,r0,save + b,n null4 + b bp_1 /* we now have less than 4 bytes to move*/ + stbys,b,m tmp3,4(0,d_addr) /* store !*/ + +bp_0: + copy tmp1,tmp2 /* switch registers used in the shift process.*/ + addibt,<=,n 4,count,done /* if count = -4 this implies that count = 0 -> done */ + +bp_1: + ldwm 4(0,s_addr),tmp1 /* get final word ! */ + vshd tmp2,tmp1,tmp3 /* position data !*/ + uxor,sbz tmp3,r0,save /* if some-byte-zero */ + b no_null /* don't goto no_null-find which null instead */ + add d_addr,count,d_addr /* get d_addr ready for stbys,e */ + extru,<> save,7,8,r0 + b found_null5 + copy r0, tmp5 + extru,<> save,15,8,r0 + b found_null5 + ldil 0x1FE000,tmp5 /* setup mask (FF000000)*/ + extru,<> save,23,8,r0 + b found_null5 + ldil 0x1FFFE0,tmp5 /* setup mask (FFFF0000)*/ + ldo -1(r0),tmp5 /* setup mask (FFFFFFFF)*/ +found_null5: + and tmp3,tmp5,tmp3 /* zero out tmp5 based on mask in tmp5*/ +no_null: + bv 0(r2) /* were done*/ + stbys,e tmp3,0(0,d_addr) /* store the data !*/ + +/* here we do ye old byte-at-a-time moves.*/ +byteloop: + addibt,=,n 4,count,done + comb,= 0,s_addr,done + stbs r0,0(d_addr) /* store null in case s_addr == NULL */ + ldbs,ma 1(s_addr),tmp1 +encore: + combt,=,n tmp1,r0, pad_null_bytes1 + stbs,ma tmp1,1(d_addr) + addibf,=,n -1,count,encore + ldbs,ma 1(s_addr),tmp1 + b,n done + +pnb_1: + addibt,=,n 4,count,done /* if count was already 0 then we're done*/ + +pad_null_bytes1: + combt,=,n count,r0,done /* if count==0 then exit */ +pad_null_bytes2: + addibf,= -1,count,pad_null_bytes2 + stbs,ma r0,1(d_addr) + b,n done + +pad_nulls: + addibf,<=,n -4,count,pad_nulls + stwm r0,4(d_addr) + b,n pnb_1 + + +null1: + extru,<> save,7,8,r0 + b found_null1 + copy r0, tmp5 + extru,<> save,15,8,r0 + b found_null1 + ldil 0x1FE000,tmp5 /* setup mask (FF000000)*/ + extru,<> save,23,8,r0 + b found_null1 + ldil 0x1FFFE0,tmp5 /* setup mask (FFFF0000)*/ + ldo -1(r0),tmp5 /* setup mask (FFFFFFFF)*/ +found_null1: + and tmp1,tmp5,tmp1 /*zero out tmp1 according to mask*/ + b pad_nulls /* nullify remaining count bytes*/ + stbys,b,m tmp1,4(0,d_addr) /* first word (account for alignment)*/ + + +null2: /* back porch case. We have less than 4 bytes to go.*/ + extru,<> save,7,8,r0 /* is null in 1st byte? */ + b found_null2 + copy r0, tmp5 + extru,<> save,15,8,r0 /* is null in 2nd byte? */ + b found_null2 + ldil 0x1FE000,tmp5 /* setup mask (FF000000)*/ + b found_null2 /* null must be in 3rd byte */ + ldil 0x1FFFE0,tmp5 /* setup mask (FFFF0000)*/ +found_null2: + and tmp1,tmp5,tmp1 /*zero out tmp1 according to mask*/ + bv 0(r2) /* we're done*/ + stbys,e tmp1,0(0,d_addr) /* last word (back porch)*/ + +null3: /* not_aligned case where null is found in first of two words--adjust count*/ + extru,<> save,7,8,r0 + b found_null3 + copy r0, tmp5 + extru,<> save,15,8,r0 + b found_null3 + ldil 0x1FE000,tmp5 /* setup mask (FF000000)*/ + extru,<> save,23,8,r0 + b found_null3 + ldil 0x1FFFE0,tmp5 /* setup mask (FFFF0000)*/ + ldo -1(r0),tmp5 /* setup mask (FFFFFFFF)*/ +found_null3: + addi 4,count,count /* fix count since null is in first of two words*/ + and tmp3,tmp5,tmp3 /*zero out tmp3 according to mask*/ + b pad_nulls /* nullify remaining count bytes*/ + stbys,b,m tmp3,4(d_addr) + +null4: /* not_aligned case where null is found in second of two words*/ + extru,<> save,7,8,r0 + b found_null4 + copy r0, tmp5 + extru,<> save,15,8,r0 + b found_null4 + ldil 0x1FE000,tmp5 /* setup mask (FF000000)*/ + extru,<> save,23,8,r0 + b found_null4 + ldil 0x1FFFE0,tmp5 /* setup mask (FFFF0000)*/ + ldo -1(r0),tmp5 /* setup mask (FFFFFFFF)*/ +found_null4: + and tmp3,tmp5,tmp3 /*zero out tmp4 according to mask*/ + b pad_nulls /* nullify remaining count bytes*/ + stbys,b,m tmp3,4(d_addr) + +done: +EXIT(strncpy) |