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Date:      Tue, 11 May 2021 10:31:07 GMT
From:      Alex Richardson <arichardson@FreeBSD.org>
To:        src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org
Subject:   git: 0e1e71400a0f - stable/13 - libc/string/bcopy.c: Use intptr_t as the copy type
Message-ID:  <202105111031.14BAV7I0085403@gitrepo.freebsd.org>

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The branch stable/13 has been updated by arichardson:

URL: https://cgit.FreeBSD.org/src/commit/?id=0e1e71400a0fa3ac6fe5a90c4d830b06eef3e71e

commit 0e1e71400a0fa3ac6fe5a90c4d830b06eef3e71e
Author:     Alex Richardson <arichardson@FreeBSD.org>
AuthorDate: 2021-04-19 23:15:57 +0000
Commit:     Alex Richardson <arichardson@FreeBSD.org>
CommitDate: 2021-05-11 08:39:26 +0000

    libc/string/bcopy.c: Use intptr_t as the copy type
    
    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
    
    (cherry picked from commit 0b4ad01d91a3b24cea00d54d25beed0f487c0183)
---
 lib/libc/string/bcopy.c | 12 +++++-------
 1 file changed, 5 insertions(+), 7 deletions(-)

diff --git a/lib/libc/string/bcopy.c b/lib/libc/string/bcopy.c
index 141416d0afec..84715d0432e3 100644
--- a/lib/libc/string/bcopy.c
+++ b/lib/libc/string/bcopy.c
@@ -40,11 +40,7 @@ __FBSDID("$FreeBSD$");
 
 #include <sys/types.h>
 
-/*
- * sizeof(word) MUST BE A POWER OF TWO
- * SO THAT wmask BELOW IS ALL ONES
- */
-typedef	int word;		/* "word" used for optimal copy speed */
+typedef	intptr_t word;		/* "word" used for optimal copy speed */
 
 #define	wsize	sizeof(word)
 #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.
 		 */
 		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;
 		TLOOP(*dst++ = *src++);
 	} else {
@@ -126,7 +123,8 @@ bcopy(const void *src0, void *dst0, size_t length)
 			TLOOP1(*--dst = *--src);
 		}
 		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;
 		TLOOP(*--dst = *--src);
 	}



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