phys_memset improvements

	. verify length argument
	. use rep stosl / stosb

diff --git a/kernel/arch/i386/klib.S b/kernel/arch/i386/klib.S
index b10595ec17be455bc7599488cb7d31bbba328205..abd43faa8f7accbfe80a46be5cfbc7cb2d553876 100644 (file)
--- a/kernel/arch/i386/klib.S
+++ b/kernel/arch/i386/klib.S
@@ -316,49 +316,35 @@ ENTRY(__user_copy_msg_pointer_failure)
 /*                             phys_memset                                  */
 /*===========================================================================*/
 /*
- * PUBLIC void phys_memset(phys_bytes source, unsigned long pattern, 
+ * PUBLIC void phys_memset(phys_bytes dst, unsigned long pattern, 
  *     phys_bytes bytecount); 
  * Fill a block of physical memory with pattern. 
  */
 ENTRY(phys_memset)
        push    %ebp
        mov     %esp, %ebp
-       push    %esi
-       push    %ebx
+       push    %edi
+       cld
+
+       mov     8(%ebp), %edi
+       mov     16(%ebp), %ecx
+       mov     12(%ebp), %eax
+       shr     $2, %ecx
+       rep stosl
 
-       mov     8(%ebp), %esi
-       mov     16(%ebp), %eax
-       mov     12(%ebp), %ebx
-       shr     $2, %eax
-fill_start:
-       mov     %ebx, (%esi)
-       add     $4, %esi
-       dec     %eax
-       jne     fill_start
 /* Any remaining bytes? */
-       mov     16(%ebp), %eax
-       and     $3, %eax
-remain_fill:
-       cmp     $0, %eax
-       je      fill_done
-       movb    12(%ebp), %bl
-       movb    %bl, (%esi)
-       add     $1, %esi
-       inc     %ebp
-       dec     %eax
-       jmp     remain_fill
-
-fill_done:
+       mov     16(%ebp), %ecx
+       and     $3, %ecx
+       rep stosb
+
 LABEL(memset_fault)            /* kernel can send us here */
        mov     $0, %eax                /* 0 means: no fault */
-       pop     %ebx
-       pop     %esi
+       pop     %edi
        pop     %ebp
        ret
 
 LABEL(memset_fault_in_kernel)          /* kernel can send us here */
-       pop     %ebx
-       pop     %esi
+       pop     %edi
        pop     %ebp
        mov     %cr2, %eax
        ret