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author | cognet <cognet@FreeBSD.org> | 2004-05-14 23:31:10 +0000 |
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committer | cognet <cognet@FreeBSD.org> | 2004-05-14 23:31:10 +0000 |
commit | 1bb11493f3079cd0feb1897cd6de4efb3d2e64d8 (patch) | |
tree | 80ef322006f800c80e22a5f973cd94ed885006e6 /sys/arm | |
parent | dd9f981b6806469475907ff28f4d52a647b7c694 (diff) | |
download | FreeBSD-src-1bb11493f3079cd0feb1897cd6de4efb3d2e64d8.zip FreeBSD-src-1bb11493f3079cd0feb1897cd6de4efb3d2e64d8.tar.gz |
Implement bzero et memset in support.S
Diffstat (limited to 'sys/arm')
-rw-r--r-- | sys/arm/arm/support.S | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/sys/arm/arm/support.S b/sys/arm/arm/support.S index bfca271..140a736 100644 --- a/sys/arm/arm/support.S +++ b/sys/arm/arm/support.S @@ -70,3 +70,164 @@ ENTRY(disable_intr) ENTRY(enable_intr) IRQenableALL +/* + * memset: Sets a block of memory to the specified value + * + * On entry: + * r0 - dest address + * r1 - byte to write + * r2 - number of bytes to write + * + * On exit: + * r0 - dest address + */ +/* LINTSTUB: Func: void bzero(void *, size_t) */ +ENTRY(bzero) + mov r3, #0x00 + b do_memset + +/* LINTSTUB: Func: void *memset(void *, int, size_t) */ +ENTRY(memset) + and r3, r1, #0xff /* We deal with bytes */ + mov r1, r2 +do_memset: + cmp r1, #0x04 /* Do we have less than 4 bytes */ + mov ip, r0 + blt .Lmemset_lessthanfour + + /* Ok first we will word align the address */ + ands r2, ip, #0x03 /* Get the bottom two bits */ + bne .Lmemset_wordunaligned /* The address is not word aligned */ + + /* We are now word aligned */ +.Lmemset_wordaligned: + orr r3, r3, r3, lsl #8 /* Extend value to 16-bits */ +#ifdef __XSCALE__ + tst ip, #0x04 /* Quad-align for Xscale */ +#else + cmp r1, #0x10 +#endif + orr r3, r3, r3, lsl #16 /* Extend value to 32-bits */ +#ifdef __XSCALE__ + subne r1, r1, #0x04 /* Quad-align if necessary */ + strne r3, [ip], #0x04 + cmp r1, #0x10 +#endif + blt .Lmemset_loop4 /* If less than 16 then use words */ + mov r2, r3 /* Duplicate data */ + cmp r1, #0x80 /* If < 128 then skip the big loop */ + blt .Lmemset_loop32 + + /* Do 128 bytes at a time */ +.Lmemset_loop128: + subs r1, r1, #0x80 +#ifdef __XSCALE__ + strged r2, [ip], #0x08 + strged r2, [ip], #0x08 + strged r2, [ip], #0x08 + strged r2, [ip], #0x08 + strged r2, [ip], #0x08 + strged r2, [ip], #0x08 + strged r2, [ip], #0x08 + strged r2, [ip], #0x08 + strged r2, [ip], #0x08 + strged r2, [ip], #0x08 + strged r2, [ip], #0x08 + strged r2, [ip], #0x08 + strged r2, [ip], #0x08 + strged r2, [ip], #0x08 + strged r2, [ip], #0x08 + strged r2, [ip], #0x08 +#else + stmgeia ip!, {r2-r3} + stmgeia ip!, {r2-r3} + stmgeia ip!, {r2-r3} + stmgeia ip!, {r2-r3} + stmgeia ip!, {r2-r3} + stmgeia ip!, {r2-r3} + stmgeia ip!, {r2-r3} + stmgeia ip!, {r2-r3} + stmgeia ip!, {r2-r3} + stmgeia ip!, {r2-r3} + stmgeia ip!, {r2-r3} + stmgeia ip!, {r2-r3} + stmgeia ip!, {r2-r3} + stmgeia ip!, {r2-r3} + stmgeia ip!, {r2-r3} + stmgeia ip!, {r2-r3} +#endif + bgt .Lmemset_loop128 + moveq pc, lr /* Zero length so just exit */ + + add r1, r1, #0x80 /* Adjust for extra sub */ + + /* Do 32 bytes at a time */ +.Lmemset_loop32: + subs r1, r1, #0x20 +#ifdef __XSCALE__ + strged r2, [ip], #0x08 + strged r2, [ip], #0x08 + strged r2, [ip], #0x08 + strged r2, [ip], #0x08 +#else + stmgeia ip!, {r2-r3} + stmgeia ip!, {r2-r3} + stmgeia ip!, {r2-r3} + stmgeia ip!, {r2-r3} +#endif + bgt .Lmemset_loop32 + moveq pc, lr /* Zero length so just exit */ + + adds r1, r1, #0x10 /* Partially adjust for extra sub */ + + /* Deal with 16 bytes or more */ +#ifdef __XSCALE__ + strged r2, [ip], #0x08 + strged r2, [ip], #0x08 +#else + stmgeia ip!, {r2-r3} + stmgeia ip!, {r2-r3} +#endif + moveq pc, lr /* Zero length so just exit */ + + addlt r1, r1, #0x10 /* Possibly adjust for extra sub */ + + /* We have at least 4 bytes so copy as words */ +.Lmemset_loop4: + subs r1, r1, #0x04 + strge r3, [ip], #0x04 + bgt .Lmemset_loop4 + moveq pc, lr /* Zero length so just exit */ + +#ifdef __XSCALE__ + /* Compensate for 64-bit alignment check */ + adds r1, r1, #0x04 + moveq pc, lr + cmp r1, #2 +#else + cmp r1, #-2 +#endif + + strb r3, [ip], #0x01 /* Set 1 byte */ + strgeb r3, [ip], #0x01 /* Set another byte */ + strgtb r3, [ip] /* and a third */ + mov pc, lr /* Exit */ + +.Lmemset_wordunaligned: + rsb r2, r2, #0x004 + strb r3, [ip], #0x01 /* Set 1 byte */ + cmp r2, #0x02 + strgeb r3, [ip], #0x01 /* Set another byte */ + sub r1, r1, r2 + strgtb r3, [ip], #0x01 /* and a third */ + cmp r1, #0x04 /* More than 4 bytes left? */ + bge .Lmemset_wordaligned /* Yup */ + +.Lmemset_lessthanfour: + cmp r1, #0x00 + moveq pc, lr /* Zero length so exit */ + strb r3, [ip], #0x01 /* Set 1 byte */ + cmp r1, #0x02 + strgeb r3, [ip], #0x01 /* Set another byte */ + strgtb r3, [ip] /* and a third */ + mov pc, lr /* Exit */ |