git.y1.nz

commit 82d5bf7a125f8144a133b9cb7c44bd0d51a9b359
parent 753bed93cf954191a60a1769fbc330e238022d38
Author: Toxa <untoxa@mail.ru>
Date:   Sun, 28 Nov 2021 18:45:02 +0300

memcmp() implementation

Diffstat:
M
gbdk-lib/include/asm/gbz80/string.h
13
+++++++++++++
M
gbdk-lib/include/asm/z80/string.h
13
+++++++++++++
M
gbdk-lib/libc/asm/gbz80/Makefile
2
+-
A
gbdk-lib/libc/asm/gbz80/_memcmp.s
46
++++++++++++++++++++++++++++++++++++++++++++++
M
gbdk-lib/libc/asm/z80/Makefile
2
+-
A
gbdk-lib/libc/asm/z80/memcmp.s
39
+++++++++++++++++++++++++++++++++++++++

6 files changed, 113 insertions(+), 2 deletions(-)
diff --git a/gbdk-lib/include/asm/gbz80/string.h b/gbdk-lib/include/asm/gbz80/string.h
@@ -128,4 +128,17 @@ int strncmp(const char *s1, const char *s2, int n);
 */
 char *strncpy(char *s1, const char *s2, int n);
 
+/** Compares buffers
+
+    @param buf1         First buffer to compare
+    @param buf2         Second buffer to compare
+    @param count        Buffer length
+
+    Returns:
+    \li > 0 if __buf1__ > __buf2__
+    \li 0 if __buf1__ == __buf2__
+    \li < 0 if __buf1__ < __buf2__
+*/
+int memcmp(const void *buf1, const void *buf2, size_t count) OLDCALL;
+
 #endif
diff --git a/gbdk-lib/include/asm/z80/string.h b/gbdk-lib/include/asm/z80/string.h
@@ -128,4 +128,17 @@ int strncmp(const char *s1, const char *s2, int n) NONBANKED;
 */
 char *strncpy(char *s1, const char *s2, int n) NONBANKED;
 
+/** Compares buffers
+
+    @param buf1         First buffer to compare
+    @param buf2         Second buffer to compare
+    @param count        Buffer length
+
+    Returns:
+    \li > 0 if __buf1__ > __buf2__
+    \li 0 if __buf1__ == __buf2__
+    \li < 0 if __buf1__ < __buf2__
+*/
+int memcmp(const void *buf1, const void *buf2, size_t count) __z88dk_callee;
+
 #endif
diff --git a/gbdk-lib/libc/asm/gbz80/Makefile b/gbdk-lib/libc/asm/gbz80/Makefile
@@ -7,7 +7,7 @@ THIS = gbz80
 ASSRC = __sdcc_call_hl.s abs.s mul.s div.s shift.s crt0_rle.s \
 	itoa.s strlen.s reverse.s labs.s ltoa.s \
 	setjmp.s atomic_flag_test_and_set.s \
-	_memcpy.s _memset.s _strcmp.s _strcpy.s \
+	_memcpy.s _memset.s _strcmp.s _strcpy.s _memcmp.s \
 	rand.s arand.s \
 	bcd.s
 
diff --git a/gbdk-lib/libc/asm/gbz80/_memcmp.s b/gbdk-lib/libc/asm/gbz80/_memcmp.s
@@ -0,0 +1,45 @@
+        .module strcmp
+
+        .area   _HOME
+
+; int memcmp(const void *buf1, const void *buf2, size_t count)
+_memcmp::
+        lda     hl,7(sp)
+        ld      a,(hl-)
+        ld      b, a
+        ld      a,(hl-)
+        ld      c, a
+        ld      a,(hl-)
+        ld      d, a
+        ld      a,(hl-)
+        ld      e, a
+        ld      a,(hl-)
+        ld      l,(hl)
+        ld      h,a
+
+        inc     b
+        inc     c
+        jr      3$
+
+1$:     
+        ld      a,(de)
+        sub     (hl)            ; s1[i]==s2[i]?
+        jr      nz, 2$          ; -> Different
+        
+        inc     de
+        inc     hl
+3$:
+        dec     c
+        jr      nz, 1$
+        dec     b
+        jr      nz, 1$
+
+        ld      de, #0
+        ret
+
+2$:
+        ld      de,#-1
+        ret     c
+
+        ld      de,#1
+        ret
+
diff --git a/gbdk-lib/libc/asm/z80/Makefile b/gbdk-lib/libc/asm/z80/Makefile
@@ -10,7 +10,7 @@ ASSRC = __strreverse.s strcpy.s strlen.s \
 	mul.s mulchar.s \
 	__itoa.s __ltoa.s \
 	__uitobcd.s __ultobcd.s \
-	memcpy.s memmove.s memset.s \
+	memcpy.s memmove.s memset.s memcmp.s \
 	setjmp.s \
 	abs.s \
 	rand.s arand.s \
diff --git a/gbdk-lib/libc/asm/z80/memcmp.s b/gbdk-lib/libc/asm/z80/memcmp.s
@@ -0,0 +1,38 @@
+        .module strcmp
+
+        .area   _HOME
+
+; int memcmp(const void *buf1, const void *buf2, size_t count)
+_memcmp::
+        pop hl
+        pop de
+        pop bc
+        ex (sp), hl
+        ex de, hl
+
+        inc     d
+        inc     e
+        jr      3$
+
+1$:     
+        ld      a,(bc)
+        sub     (hl)            ; s1[i]==s2[i]?
+        jr      nz, 2$          ; -> Different
+        
+        inc     bc
+        inc     hl
+3$:
+        dec     e
+        jr      nz, 1$
+        dec     d
+        jr      nz, 1$
+
+        ld      hl, #0
+        ret
+
+2$:
+        ld      hl,#-1
+        ret     c
+
+        ld      hl,#1
+        ret
+

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