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libc/string/bcopy.c: Use intptr_t as the copy type

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While most 64-bit architectures have an assembly implementation of this
file RISC-V does not. As we now copy 8 bytes instead of 4 it should speed
up RISC-V. Using intptr_t instead of int also allows using this file for
CHERI pure-capability code since trying to copy pointers using integer
loads/stores will invalidate pointers.

Reviewed By:	kib
Obtained from:	CheriBSD (partially)
MFC after:	1 week
Differential Revision: https://reviews.freebsd.org/D29535
This commit is contained in:
Alex Richardson 2021-04-20 00:15:57 +01:00
parent bbd421cdf6
commit 0b4ad01d91
1 changed files with 5 additions and 7 deletions
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12
lib/libc/string/bcopy.c
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@ -40,11 +40,7 @@ __FBSDID("$FreeBSD$");
#include <sys/types.h> #include <sys/types.h>
/* typedef intptr_t word; /* "word" used for optimal copy speed */
* sizeof(word) MUST BE A POWER OF TWO
* SO THAT wmask BELOW IS ALL ONES
*/
typedef int word; /* "word" used for optimal copy speed */
#define wsize sizeof(word) #define wsize sizeof(word)
#define wmask (wsize - 1) #define wmask (wsize - 1)
@ -105,7 +101,8 @@ bcopy(const void *src0, void *dst0, size_t length)
* Copy whole words, then mop up any trailing bytes. * Copy whole words, then mop up any trailing bytes.
*/ */
t = length / wsize; t = length / wsize;
TLOOP(*(word *)dst = *(word *)src; src += wsize; dst += wsize); TLOOP(*(word *)(void *)dst = *(const word *)(const void *)src;
src += wsize; dst += wsize);
t = length & wmask; t = length & wmask;
TLOOP(*dst++ = *src++); TLOOP(*dst++ = *src++);
} else { } else {
@ -126,7 +123,8 @@ bcopy(const void *src0, void *dst0, size_t length)
TLOOP1(*--dst = *--src); TLOOP1(*--dst = *--src);
} }
t = length / wsize; t = length / wsize;
TLOOP(src -= wsize; dst -= wsize; *(word *)dst = *(word *)src); TLOOP(src -= wsize; dst -= wsize;
*(word *)(void *)dst = *(const word *)(const void *)src);
t = length & wmask; t = length & wmask;
TLOOP(*--dst = *--src); TLOOP(*--dst = *--src);
} }