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-rw-r--r--arch/hexagon/lib/memcpy.S529
1 files changed, 529 insertions, 0 deletions
diff --git a/arch/hexagon/lib/memcpy.S b/arch/hexagon/lib/memcpy.S
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+/* 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