ldlinux: readdir: trivial optimization

Trivially optimize the readdir code

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

diff --git a/core/ldlinux.asm b/core/ldlinux.asm
index a06e727..21a3a35 100644 (file)
--- a/core/ldlinux.asm
+++ b/core/ldlinux.asm
@@ -1446,12 +1446,11 @@ readdir:
 .vfat_cp_ln:           ; Copy VFAT line
                dec al          ; Store the next line we need
                mov dx,ax       ; Use DX to store the progress
-               mov bx,13
-               mov ah,0
-               mul bl          ; Offset for DI
+               mov cx,13       ; 13 characters per VFAT DIRENT
+               cbw             ; AH <- 0
+               mul cl          ; Offset for DI
                add di,ax       ; Increment DI
                inc si          ; Align to the real characters
-               mov cx,13       ; 13 characters per VFAT DIRENT
 .vfat_cp_chr:
                gs lodsw        ; Unicode here!!
                mov bp,ds