/* SPDX-License-Identifier: GPL-2.0-only */ /* * Copyright (c) 2010-2011, The Linux Foundation. All rights reserved. */ /* * Description * * library function for memcpy where length bytes are copied from * ptr_in to ptr_out. ptr_out is returned unchanged. * Allows any combination of alignment on input and output pointers * and length from 0 to 2^32-1 * * Restrictions * The arrays should not overlap, the program will produce undefined output * if they do. * For blocks less than 16 bytes a byte by byte copy is performed. For * 8byte alignments, and length multiples, a dword copy is performed up to * 96bytes * History * * DJH 5/15/09 Initial version 1.0 * DJH 6/ 1/09 Version 1.1 modified ABI to inlcude R16-R19 * DJH 7/12/09 Version 1.2 optimized codesize down to 760 was 840 * DJH 10/14/09 Version 1.3 added special loop for aligned case, was * overreading bloated codesize back up to 892 * DJH 4/20/10 Version 1.4 fixed Ldword_loop_epilog loop to prevent loads * occurring if only 1 left outstanding, fixes bug * # 3888, corrected for all alignments. Peeled off * 1 32byte chunk from kernel loop and extended 8byte * loop at end to solve all combinations and prevent * over read. Fixed Ldword_loop_prolog to prevent * overread for blocks less than 48bytes. Reduced * codesize to 752 bytes * DJH 4/21/10 version 1.5 1.4 fix broke code for input block ends not * aligned to dword boundaries,underwriting by 1 * byte, added detection for this and fixed. A * little bloat. * DJH 4/23/10 version 1.6 corrected stack error, R20 was not being restored * always, fixed the error of R20 being modified * before it was being saved * Natural c model * =============== * void * memcpy(char * ptr_out, char * ptr_in, int length) { * int i; * if(length) for(i=0; i < length; i++) { ptr_out[i] = ptr_in[i]; } * return(ptr_out); * } * * Optimized memcpy function * ========================= * void * memcpy(char * ptr_out, char * ptr_in, int len) { * int i, prolog, kernel, epilog, mask; * u8 offset; * s64 data0, dataF8, data70; * * s64 * ptr8_in; * s64 * ptr8_out; * s32 * ptr4; * s16 * ptr2; * * offset = ((int) ptr_in) & 7; * ptr8_in = (s64 *) &ptr_in[-offset]; //read in the aligned pointers * * data70 = *ptr8_in++; * dataF8 = *ptr8_in++; * * data0 = HEXAGON_P_valignb_PPp(dataF8, data70, offset); * * prolog = 32 - ((int) ptr_out); * mask = 0x7fffffff >> HEXAGON_R_cl0_R(len); * prolog = prolog & mask; * kernel = len - prolog; * epilog = kernel & 0x1F; * kernel = kernel>>5; * * if (prolog & 1) { ptr_out[0] = (u8) data0; data0 >>= 8; ptr_out += 1;} * ptr2 = (s16 *) &ptr_out[0]; * if (prolog & 2) { ptr2[0] = (u16) data0; data0 >>= 16; ptr_out += 2;} * ptr4 = (s32 *) &ptr_out[0]; * if (prolog & 4) { ptr4[0] = (u32) data0; data0 >>= 32; ptr_out += 4;} * * offset = offset + (prolog & 7); * if (offset >= 8) { * data70 = dataF8; * dataF8 = *ptr8_in++; * } * offset = offset & 0x7; * * prolog = prolog >> 3; * if (prolog) for (i=0; i < prolog; i++) { * data0 = HEXAGON_P_valignb_PPp(dataF8, data70, offset); * ptr8_out = (s64 *) &ptr_out[0]; *ptr8_out = data0; ptr_out += 8; * data70 = dataF8; * dataF8 = *ptr8_in++; * } * if(kernel) { kernel -= 1; epilog += 32; } * if(kernel) for(i=0; i < kernel; i++) { * data0 = HEXAGON_P_valignb_PPp(dataF8, data70, offset); * ptr8_out = (s64 *) &ptr_out[0]; *ptr8_out = data0; ptr_out += 8; * data70 = *ptr8_in++; * * data0 = HEXAGON_P_valignb_PPp(data70, dataF8, offset); * ptr8_out = (s64 *) &ptr_out[0]; *ptr8_out = data0; ptr_out += 8; * dataF8 = *ptr8_in++; * * data0 = HEXAGON_P_valignb_PPp(dataF8, data70, offset); * ptr8_out = (s64 *) &ptr_out[0]; *ptr8_out = data0; ptr_out += 8; * data70 = *ptr8_in++; * * data0 = HEXAGON_P_valignb_PPp(data70, dataF8, offset); * ptr8_out = (s64 *) &ptr_out[0]; *ptr8_out = data0; ptr_out += 8; * dataF8 = *ptr8_in++; * } * epilogdws = epilog >> 3; * if (epilogdws) for (i=0; i < epilogdws; i++) { * data0 = HEXAGON_P_valignb_PPp(dataF8, data70, offset); * ptr8_out = (s64 *) &ptr_out[0]; *ptr8_out = data0; ptr_out += 8; * data70 = dataF8; * dataF8 = *ptr8_in++; * } * data0 = HEXAGON_P_valignb_PPp(dataF8, data70, offset); * * ptr4 = (s32 *) &ptr_out[0]; * if (epilog & 4) { ptr4[0] = (u32) data0; data0 >>= 32; ptr_out += 4;} * ptr2 = (s16 *) &ptr_out[0]; * if (epilog & 2) { ptr2[0] = (u16) data0; data0 >>= 16; ptr_out += 2;} * if (epilog & 1) { *ptr_out++ = (u8) data0; } * * return(ptr_out - length); * } * * Codesize : 784 bytes */ #define ptr_out R0 /* destination pounter */ #define ptr_in R1 /* source pointer */ #define len R2 /* length of copy in bytes */ #define data70 R13:12 /* lo 8 bytes of non-aligned transfer */ #define dataF8 R11:10 /* hi 8 bytes of non-aligned transfer */ #define ldata0 R7:6 /* even 8 bytes chunks */ #define ldata1 R25:24 /* odd 8 bytes chunks */ #define data1 R7 /* lower 8 bytes of ldata1 */ #define data0 R6 /* lower 8 bytes of ldata0 */ #define ifbyte p0 /* if transfer has bytes in epilog/prolog */ #define ifhword p0 /* if transfer has shorts in epilog/prolog */ #define ifword p0 /* if transfer has words in epilog/prolog */ #define noprolog p0 /* no prolog, xfer starts at 32byte */ #define nokernel p1 /* no 32byte multiple block in the transfer */ #define noepilog p0 /* no epilog, xfer ends on 32byte boundary */ #define align p2 /* alignment of input rel to 8byte boundary */ #define kernel1 p0 /* kernel count == 1 */ #define dalign R25 /* rel alignment of input to output data */ #define star3 R16 /* number bytes in prolog - dwords */ #define rest R8 /* length - prolog bytes */ #define back R7 /* nr bytes > dword boundary in src block */ #define epilog R3 /* bytes in epilog */ #define inc R15:14 /* inc kernel by -1 and defetch ptr by 32 */ #define kernel R4 /* number of 32byte chunks in kernel */ #define ptr_in_p_128 R5 /* pointer for prefetch of input data */ #define mask R8 /* mask used to determine prolog size */ #define shift R8 /* used to work a shifter to extract bytes */ #define shift2 R5 /* in epilog to workshifter to extract bytes */ #define prolog R15 /* bytes in prolog */ #define epilogdws R15 /* number dwords in epilog */ #define shiftb R14 /* used to extract bytes */ #define offset R9 /* same as align in reg */ #define ptr_out_p_32 R17 /* pointer to output dczero */ #define align888 R14 /* if simple dword loop can be used */ #define len8 R9 /* number of dwords in length */ #define over R20 /* nr of bytes > last inp buf dword boundary */ #define ptr_in_p_128kernel R5:4 /* packed fetch pointer & kernel cnt */ .section .text .p2align 4 .global memcpy .type memcpy, @function memcpy: { p2 = cmp.eq(len, #0); /* =0 */ align888 = or(ptr_in, ptr_out); /* %8 < 97 */ p0 = cmp.gtu(len, #23); /* %1, <24 */ p1 = cmp.eq(ptr_in, ptr_out); /* attempt to overwrite self */ } { p1 = or(p2, p1); p3 = cmp.gtu(len, #95); /* %8 < 97 */ align888 = or(align888, len); /* %8 < 97 */ len8 = lsr(len, #3); /* %8 < 97 */ } { dcfetch(ptr_in); /* zero/ptrin=ptrout causes fetch */ p2 = bitsclr(align888, #7); /* %8 < 97 */ if(p1) jumpr r31; /* =0 */ } { p2 = and(p2,!p3); /* %8 < 97 */ if (p2.new) len = add(len, #-8); /* %8 < 97 */ if (p2.new) jump:NT .Ldwordaligned; /* %8 < 97 */ } { if(!p0) jump .Lbytes23orless; /* %1, <24 */ mask.l = #LO(0x7fffffff); /* all bytes before line multiples of data */ prolog = sub(#0, ptr_out); } { /* save r31 on stack, decrement sp by 16 */ allocframe(#24); mask.h = #HI(0x7fffffff); ptr_in_p_128 = add(ptr_in, #32); back = cl0(len); } { memd(sp+#0) = R17:16; /* save r16,r17 on stack6 */ r31.l = #LO(.Lmemcpy_return); /* set up final return pointer */ prolog &= lsr(mask, back); offset = and(ptr_in, #7); } { memd(sp+#8) = R25:24; /* save r25,r24 on stack */ dalign = sub(ptr_out, ptr_in); r31.h = #HI(.Lmemcpy_return); /* set up final return pointer */ } { /* see if there if input buffer end if aligned */ over = add(len, ptr_in); back = add(len, offset); memd(sp+#16) = R21:20; /* save r20,r21 on stack */ } { noprolog = bitsclr(prolog, #7); prolog = and(prolog, #31); dcfetch(ptr_in_p_128); ptr_in_p_128 = add(ptr_in_p_128, #32); } { kernel = sub(len, prolog); shift = asl(prolog, #3); star3 = and(prolog, #7); ptr_in = and(ptr_in, #-8); } { prolog = lsr(prolog, #3); epilog = and(kernel, #31); ptr_out_p_32 = add(ptr_out, prolog); over = and(over, #7); } { p3 = cmp.gtu(back, #8); kernel = lsr(kernel, #5); dcfetch(ptr_in_p_128); ptr_in_p_128 = add(ptr_in_p_128, #32); } { p1 = cmp.eq(prolog, #0); if(!p1.new) prolog = add(prolog, #1); dcfetch(ptr_in_p_128); /* reserve the line 64bytes on */ ptr_in_p_128 = add(ptr_in_p_128, #32); } { nokernel = cmp.eq(kernel,#0); dcfetch(ptr_in_p_128); /* reserve the line 64bytes on */ ptr_in_p_128 = add(ptr_in_p_128, #32); shiftb = and(shift, #8); } { dcfetch(ptr_in_p_128); /* reserve the line 64bytes on */ ptr_in_p_128 = add(ptr_in_p_128, #32); if(nokernel) jump .Lskip64; p2 = cmp.eq(kernel, #1); /* skip ovr if kernel == 0 */ } { dczeroa(ptr_out_p_32); /* don't advance pointer */ if(!p2) ptr_out_p_32 = add(ptr_out_p_32, #32); } { dalign = and(dalign, #31); dczeroa(ptr_out_p_32); } .Lskip64: { data70 = memd(ptr_in++#16); if(p3) dataF8 = memd(ptr_in+#8); if(noprolog) jump .Lnoprolog32; align = offset; } /* upto initial 7 bytes */ { ldata0 = valignb(dataF8, data70, align); ifbyte = tstbit(shift,#3); offset = add(offset, star3); } { if(ifbyte) memb(ptr_out++#1) = data0; ldata0 = lsr(ldata0, shiftb); shiftb = and(shift, #16); ifhword = tstbit(shift,#4); } { if(ifhword) memh(ptr_out++#2) = data0; ldata0 = lsr(ldata0, shiftb); ifword = tstbit(shift,#5); p2 = cmp.gtu(offset, #7); } { if(ifword) memw(ptr_out++#4) = data0; if(p2) data70 = dataF8; if(p2) dataF8 = memd(ptr_in++#8); /* another 8 bytes */ align = offset; } .Lnoprolog32: { p3 = sp1loop0(.Ldword_loop_prolog, prolog) rest = sub(len, star3); /* whats left after the loop */ p0 = cmp.gt(over, #0); } if(p0) rest = add(rest, #16); .Ldword_loop_prolog: { if(p3) memd(ptr_out++#8) = ldata0; ldata0 = valignb(dataF8, data70, align); p0 = cmp.gt(rest, #16); } { data70 = dataF8; if(p0) dataF8 = memd(ptr_in++#8); rest = add(rest, #-8); }:endloop0 .Lkernel: { /* kernel is at least 32bytes */ p3 = cmp.gtu(kernel, #0); /* last itn. remove edge effects */ if(p3.new) kernel = add(kernel, #-1); /* dealt with in last dword loop */ if(p3.new) epilog = add(epilog, #32); } { nokernel = cmp.eq(kernel, #0); /* after adjustment, recheck */ if(nokernel.new) jump:NT .Lepilog; /* likely not taken */ inc = combine(#32, #-1); p3 = cmp.gtu(dalign, #24); } { if(p3) jump .Lodd_alignment; } { loop0(.Loword_loop_25to31, kernel); kernel1 = cmp.gtu(kernel, #1); rest = kernel; } .falign .Loword_loop_25to31: { dcfetch(ptr_in_p_128); /* prefetch 4 lines ahead */ if(kernel1) ptr_out_p_32 = add(ptr_out_p_32, #32); } { dczeroa(ptr_out_p_32); /* reserve the next 32bytes in cache */ p3 = cmp.eq(kernel, rest); } { /* kernel -= 1 */ ptr_in_p_128kernel = vaddw(ptr_in_p_128kernel, inc); /* kill write on first iteration */ if(!p3) memd(ptr_out++#8) = ldata1; ldata1 = valignb(dataF8, data70, align); data70 = memd(ptr_in++#8); } { memd(ptr_out++#8) = ldata0; ldata0 = valignb(data70, dataF8, align); dataF8 = memd(ptr_in++#8); } { memd(ptr_out++#8) = ldata1; ldata1 = valignb(dataF8, data70, align); data70 = memd(ptr_in++#8); } { memd(ptr_out++#8) = ldata0; ldata0 = valignb(data70, dataF8, align); dataF8 = memd(ptr_in++#8); kernel1 = cmp.gtu(kernel, #1); }:endloop0 { memd(ptr_out++#8) = ldata1; jump .Lepilog; } .Lodd_alignment: { loop0(.Loword_loop_00to24, kernel); kernel1 = cmp.gtu(kernel, #1); rest = add(kernel, #-1); } .falign .Loword_loop_00to24: { dcfetch(ptr_in_p_128); /* prefetch 4 lines ahead */ ptr_in_p_128kernel = vaddw(ptr_in_p_128kernel, inc); if(kernel1) ptr_out_p_32 = add(ptr_out_p_32, #32); } { dczeroa(ptr_out_p_32); /* reserve the next 32bytes in cache */ } { memd(ptr_out++#8) = ldata0; ldata0 = valignb(dataF8, data70, align); data70 = memd(ptr_in++#8); } { memd(ptr_out++#8) = ldata0; ldata0 = valignb(data70, dataF8, align); dataF8 = memd(ptr_in++#8); } { memd(ptr_out++#8) = ldata0; ldata0 = valignb(dataF8, data70, align); data70 = memd(ptr_in++#8); } { memd(ptr_out++#8) = ldata0; ldata0 = valignb(data70, dataF8, align); dataF8 = memd(ptr_in++#8); kernel1 = cmp.gtu(kernel, #1); }:endloop0 .Lepilog: { noepilog = cmp.eq(epilog,#0); epilogdws = lsr(epilog, #3); kernel = and(epilog, #7); } { if(noepilog) jumpr r31; if(noepilog) ptr_out = sub(ptr_out, len); p3 = cmp.eq(epilogdws, #0); shift2 = asl(epilog, #3); } { shiftb = and(shift2, #32); ifword = tstbit(epilog,#2); if(p3) jump .Lepilog60; if(!p3) epilog = add(epilog, #-16); } { loop0(.Ldword_loop_epilog, epilogdws); /* stop criteria is lsbs unless = 0 then its 8 */ p3 = cmp.eq(kernel, #0); if(p3.new) kernel= #8; p1 = cmp.gt(over, #0); } /* if not aligned to end of buffer execute 1 more iteration */ if(p1) kernel= #0; .Ldword_loop_epilog: { memd(ptr_out++#8) = ldata0; ldata0 = valignb(dataF8, data70, align); p3 = cmp.gt(epilog, kernel); } { data70 = dataF8; if(p3) dataF8 = memd(ptr_in++#8); epilog = add(epilog, #-8); }:endloop0 /* copy last 7 bytes */ .Lepilog60: { if(ifword) memw(ptr_out++#4) = data0; ldata0 = lsr(ldata0, shiftb); ifhword = tstbit(epilog,#1); shiftb = and(shift2, #16); } { if(ifhword) memh(ptr_out++#2) = data0; ldata0 = lsr(ldata0, shiftb); ifbyte = tstbit(epilog,#0); if(ifbyte.new) len = add(len, #-1); } { if(ifbyte) memb(ptr_out) = data0; ptr_out = sub(ptr_out, len); /* return dest pointer */ jumpr r31; } /* do byte copy for small n */ .Lbytes23orless: { p3 = sp1loop0(.Lbyte_copy, len); len = add(len, #-1); } .Lbyte_copy: { data0 = memb(ptr_in++#1); if(p3) memb(ptr_out++#1) = data0; }:endloop0 { memb(ptr_out) = data0; ptr_out = sub(ptr_out, len); jumpr r31; } /* do dword copies for aligned in, out and length */ .Ldwordaligned: { p3 = sp1loop0(.Ldword_copy, len8); } .Ldword_copy: { if(p3) memd(ptr_out++#8) = ldata0; ldata0 = memd(ptr_in++#8); }:endloop0 { memd(ptr_out) = ldata0; ptr_out = sub(ptr_out, len); jumpr r31; /* return to function caller */ } .Lmemcpy_return: r21:20 = memd(sp+#16); /* restore r20+r21 */ { r25:24 = memd(sp+#8); /* restore r24+r25 */ r17:16 = memd(sp+#0); /* restore r16+r17 */ } deallocframe; /* restore r31 and incrment stack by 16 */ jumpr r31
