Changeset 8e3f47b3 in mainline

Timestamp:

2005-10-04T22:06:07Z (19 years ago)

Author:

Sergey Bondari <bondari@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

1084a784

Parents:

ce031f0

Message:

ia-32 memcmp inline

Location:

arch/ia32

Files:

• include/memstr.h (modified) (2 diffs)
• src/asm.S (modified) (2 diffs)

arch/ia32/include/memstr.h

@@ -32 +32 @@
 extern void memsetw(__address dst, size_t cnt, __u16 x);
 extern void memsetb(__address dst, size_t cnt, __u8 x);
-
-extern int memcmp(__address src, __address dst, int cnt);
 
 /** Copy memory
@@ -72 +70 @@
 
 
+/** Compare memory
+ *
+ * Compare a given number of bytes (3rd argument)
+ * at memory locations defined by 1st and 2nd argument
+ * for equality. If memory is equal, returns 0.
+ *
+ * @param pointer 1
+ * @param pointer 2
+ * @param number of bytes
+ * @return 0 on match or non-zero if different
+ */
+static inline int memcmp(const void * mem1, const void * mem2, size_t cnt)
+{
+        __u32 d0, d1, d2;
+        int ret;
+        
+        __asm__ (
+                "repe cmpsb\n\t"
+                "je 1f\n\t"
+                "movl %3, %0\n\t"
+                "addl $1, %0\n\t"
+                "1:\n"
+                : "=a" (ret), "=%S" (d0), "=&D" (d1), "=&c" (d2)
+                : "0" (0), "1" (mem1), "2" (mem2), "3" (cnt)
+        );
+        
+        return ret;
+}
 
 #endif

arch/ia32/src/asm.S

@@ -40 +40 @@
 .global memsetb
 .global memsetw
-.global memcmp
-
 
 ## Turn paging on
@@ -200 +198 @@
         pop %eax
 
-        ret
-
-
-## Compare memory regions for equality
-#
-# Compare a given number of bytes (3rd argument)
-# at memory locations defined by 1st and 2nd argument
-# for equality. If the bytes are equal, EAX contains 0.
-#
-SRC=12
-DST=16
-CNT=20
-memcmp:
-        push %esi
-        push %edi
-
-        movl CNT(%esp),%ecx
-        movl DST(%esp),%edi
-        movl SRC(%esp),%esi
-
-        repe cmpsb %es:(%edi),%ds:(%esi)
-        movl %ecx,%eax          # %ecx contains the return value (zero on success)
-
-        pop %edi
-        pop %esi
-        
         ret