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authorPaul Mundt <lethal@linux-sh.org>2008-12-12 16:34:44 +0900
committerPaul Mundt <lethal@linux-sh.org>2008-12-22 18:44:05 +0900
commit4466b20cfcfa718ff515b9e3886749cc025e2005 (patch)
treef12402e006de74df252dff03d455af0a9e2bfa0b /arch/sh/lib64/memcpy.S
parent776d6c298aad42c2b8f191fa9ad826075e4d588c (diff)
sh: Add SH-5 optimized memcpy()/memset()/strcpy()/strlen().
Adopted from the uClibc optimized string versions. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Diffstat (limited to 'arch/sh/lib64/memcpy.S')
-rw-r--r--arch/sh/lib64/memcpy.S201
1 files changed, 201 insertions, 0 deletions
diff --git a/arch/sh/lib64/memcpy.S b/arch/sh/lib64/memcpy.S
new file mode 100644
index 00000000000..dd300c372ce
--- /dev/null
+++ b/arch/sh/lib64/memcpy.S
@@ -0,0 +1,201 @@
+/* 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.
+!
+
+ .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