Changeset 1174 in vbox for trunk/src/VBox/Runtime/string/strcmp.asm

Timestamp:

Mar 3, 2007 11:49:53 PM (18 years ago)

Author:

vboxsync

Message:

memcmp, strchr, strcmp.

File:

• trunk/src/VBox/Runtime/string/strcmp.asm (copied) (copied from trunk/src/VBox/Runtime/string/memcpy.asm ) (2 diffs)

trunk/src/VBox/Runtime/string/strcmp.asm

@@ -1 +1 @@
 ; $Id$
 ;; @file
-; InnoTek Portable Runtime - No-CRT memcpy - AMD64 & X86.
+; InnoTek Portable Runtime - No-CRT strcmp - AMD64 & X86.
 ;
 
@@ -22 +22 @@
 %include "iprt/asmdefs.mac"
 
+BEGINCODE
+
 ;;
-; @param    pvDst   gcc: rdi  msc: rcx  x86:[esp+4]
-; @param    pvSrc   gcc: rsi  msc: rdx  x86:[esp+8]
-; @param    cb      gcc: rdx  msc: r8   x86:[esp+0ch]
-BEGINPROC RT_NOCRT(memcpy)
-        cld
-
-        ; Do the bulk of the work.
+; @param    psz1   gcc: rdi  msc: rcx  x86:[esp+4]
+; @param    psz2   gcc: rsi  msc: rdx  x86:[esp+8]
+BEGINPROC RT_NOCRT(strcmp)
+        ; input
 %ifdef __AMD64__
  %ifdef ASM_CALL64_MSC
-        mov     r10, rdi                ; save
-        mov     r11, rsi                ; save
-        mov     rdi, rcx
-        mov     rsi, rdx
-        mov     rcx, r8
-        mov     rdx, r8
+  %define psz1 rcx
+  %define psz2 rdx
  %else
-        mov     rcx, rdx
+  %define psz1 rdi
+  %define psz2 rsi
  %endif
-        mov     rax, rdi                ; save the return value
-        shr     rcx, 3
-        rep movsq
 %else
-        push    edi
-        push    esi
-
-        mov     ecx, [esp + 0ch + 8]
-        mov     edi, [esp + 04h + 8]
-        mov     esi, [esp + 08h + 8]
-        mov     edx, ecx
-        mov     eax, edi                ; save the return value
-        shl     ecx, 2
-        rep movsd
+        mov     ecx, [esp + 4]
+        mov     edx, [esp + 8]
+  %define psz1 ecx
+  %define psz2 edx
 %endif
 
-        ; The remaining bytes.
-%ifdef __AMD64__
-        test    dl, 4
-        jz      .dont_move_dword
-        movsd
-%endif
-.dont_move_dword:
-        test    dl, 2
-        jz      .dont_move_word
-        movsw
-.dont_move_word:
-        test    dl, 1
-        jz      .dont_move_byte
-        movsb
-.dont_move_byte:
+        ;
+        ; The loop.
+        ;
+.next:
+        mov     al, [psz1]
+        mov     ah, [psz2]
+        cmp     al, ah
+        jne     .not_equal
+        test    al, al
+        jz      .equal
 
-%ifdef __AMD64__
- %ifdef ASM_CALL64_MSC
-        mov     rdi, r10
-        mov     rsi, r11
- %endif
-%else
-        pop     esi
-        pop     edi
-%endif
+        mov     al, [psz1 + 1]
+        mov     ah, [psz2 + 1]
+        cmp     al, ah
+        jne     .not_equal
+        test    al, al
+        jz      .equal
+        inc     psz1
+        inc     psz2
+
+        mov     al, [psz1 + 2]
+        mov     ah, [psz2 + 2]
+        cmp     al, ah
+        jne     .not_equal
+        test    al, al
+        jz      .equal
+        inc     psz1
+        inc     psz2
+
+        mov     al, [psz1 + 3]
+        mov     ah, [psz2 + 3]
+        cmp     al, ah
+        jne     .not_equal
+        test    al, al
+        jz      .equal
+
+        add     psz1, 4
+        add     psz2, 4
+        jmp     .next
+
+.equal:
+        xor     eax, eax
         ret
-ENDPROC RT_NOCRT(memcpy)
 
+.not_equal:
+        movzx   ecx, ah
+        and     eax, 0ffh
+        sub     eax, ecx
+        ret
+ENDPROC RT_NOCRT(strcmp)
+