/* Cloned and hacked for uClibc by Paul Mundt, December 2003 */ /* Modified by SuperH, Inc. September 2003 */ ! ! Fast SH memcpy ! ! by Toshiyasu Morita (tm@netcom.com) ! hacked by J"orn Rernnecke (joern.rennecke@superh.com) ("o for o-umlaut) ! SH5 code Copyright 2002 SuperH Ltd. ! ! Entry: ARG0: destination pointer ! ARG1: source pointer ! ARG2: byte count ! ! Exit: RESULT: destination pointer ! any other registers in the range r0-r7: trashed ! ! Notes: Usually one wants to do small reads and write a longword, but ! unfortunately it is difficult in some cases to concatanate bytes ! into a longword on the SH, so this does a longword read and small ! writes. ! ! This implementation makes two assumptions about how it is called: ! ! 1.: If the byte count is nonzero, the address of the last byte to be ! copied is unsigned greater than the address of the first byte to ! be copied. This could be easily swapped for a signed comparison, ! but the algorithm used needs some comparison. ! ! 2.: When there are two or three bytes in the last word of an 11-or-more ! bytes memory chunk to b copied, the rest of the word can be read ! without side effects. ! This could be easily changed by increasing the minumum size of ! a fast memcpy and the amount subtracted from r7 before L_2l_loop be 2, ! however, this would cost a few extra cyles on average. ! For SHmedia, the assumption is that any quadword can be read in its ! enirety if at least one byte is included in the copy. ! #include <features.h> .section .text..SHmedia32,"ax" .globl memcpy .type memcpy, @function .align 5 memcpy: #define LDUAQ(P,O,D0,D1) ldlo.q P,O,D0; ldhi.q P,O+7,D1 #define STUAQ(P,O,D0,D1) stlo.q P,O,D0; sthi.q P,O+7,D1 #define LDUAL(P,O,D0,D1) ldlo.l P,O,D0; ldhi.l P,O+3,D1 #define STUAL(P,O,D0,D1) stlo.l P,O,D0; sthi.l P,O+3,D1 ld.b r3,0,r63 pta/l Large,tr0 movi 25,r0 bgeu/u r4,r0,tr0 nsb r4,r0 shlli r0,5,r0 movi (L1-L0+63*32 + 1) & 0xffff,r1 sub r1, r0, r0 L0: ptrel r0,tr0 add r2,r4,r5 ptabs r18,tr1 add r3,r4,r6 blink tr0,r63 /* Rearranged to make cut2 safe */ .balign 8 L4_7: /* 4..7 byte memcpy cntd. */ stlo.l r2, 0, r0 or r6, r7, r6 sthi.l r5, -1, r6 stlo.l r5, -4, r6 blink tr1,r63 .balign 8 L1: /* 0 byte memcpy */ nop blink tr1,r63 nop nop nop nop L2_3: /* 2 or 3 byte memcpy cntd. */ st.b r5,-1,r6 blink tr1,r63 /* 1 byte memcpy */ ld.b r3,0,r0 st.b r2,0,r0 blink tr1,r63 L8_15: /* 8..15 byte memcpy cntd. */ stlo.q r2, 0, r0 or r6, r7, r6 sthi.q r5, -1, r6 stlo.q r5, -8, r6 blink tr1,r63 /* 2 or 3 byte memcpy */ ld.b r3,0,r0 ld.b r2,0,r63 ld.b r3,1,r1 st.b r2,0,r0 pta/l L2_3,tr0 ld.b r6,-1,r6 st.b r2,1,r1 blink tr0, r63 /* 4 .. 7 byte memcpy */ LDUAL (r3, 0, r0, r1) pta L4_7, tr0 ldlo.l r6, -4, r7 or r0, r1, r0 sthi.l r2, 3, r0 ldhi.l r6, -1, r6 blink tr0, r63 /* 8 .. 15 byte memcpy */ LDUAQ (r3, 0, r0, r1) pta L8_15, tr0 ldlo.q r6, -8, r7 or r0, r1, r0 sthi.q r2, 7, r0 ldhi.q r6, -1, r6 blink tr0, r63 /* 16 .. 24 byte memcpy */ LDUAQ (r3, 0, r0, r1) LDUAQ (r3, 8, r8, r9) or r0, r1, r0 sthi.q r2, 7, r0 or r8, r9, r8 sthi.q r2, 15, r8 ldlo.q r6, -8, r7 ldhi.q r6, -1, r6 stlo.q r2, 8, r8 stlo.q r2, 0, r0 or r6, r7, r6 sthi.q r5, -1, r6 stlo.q r5, -8, r6 blink tr1,r63 Large: ld.b r2, 0, r63 pta/l Loop_ua, tr1 ori r3, -8, r7 sub r2, r7, r22 sub r3, r2, r6 add r2, r4, r5 ldlo.q r3, 0, r0 addi r5, -16, r5 movi 64+8, r27 /* could subtract r7 from that. */ stlo.q r2, 0, r0 sthi.q r2, 7, r0 ldx.q r22, r6, r0 bgtu/l r27, r4, tr1 addi r5, -48, r27 pta/l Loop_line, tr0 addi r6, 64, r36 addi r6, -24, r19 addi r6, -16, r20 addi r6, -8, r21 Loop_line: ldx.q r22, r36, r63 alloco r22, 32 addi r22, 32, r22 ldx.q r22, r19, r23 sthi.q r22, -25, r0 ldx.q r22, r20, r24 ldx.q r22, r21, r25 stlo.q r22, -32, r0 ldx.q r22, r6, r0 sthi.q r22, -17, r23 sthi.q r22, -9, r24 sthi.q r22, -1, r25 stlo.q r22, -24, r23 stlo.q r22, -16, r24 stlo.q r22, -8, r25 bgeu r27, r22, tr0 Loop_ua: addi r22, 8, r22 sthi.q r22, -1, r0 stlo.q r22, -8, r0 ldx.q r22, r6, r0 bgtu/l r5, r22, tr1 add r3, r4, r7 ldlo.q r7, -8, r1 sthi.q r22, 7, r0 ldhi.q r7, -1, r7 ptabs r18,tr1 stlo.q r22, 0, r0 or r1, r7, r1 sthi.q r5, 15, r1 stlo.q r5, 8, r1 blink tr1, r63 .size memcpy,.-memcpy libc_hidden_def(memcpy)