aa64: finalise context switch, page fault handler and syscall

[lunaix-os.git] / lunaix-os / arch / aarch64 / klibc / string.c

diff --git a/lunaix-os/arch/aarch64/klibc/string.c b/lunaix-os/arch/aarch64/klibc/string.c
new file mode 100644 (file)
index 0000000..f590e0b
--- /dev/null
+++ b/lunaix-os/arch/aarch64/klibc/string.c
@@ -0,0 +1,91 @@
+#include <klibc/string.h>
+#include <lunaix/compiler.h>
+
+void*
+memcpy(void* dest, const void* src, unsigned long num)
+{
+    if (unlikely(!num))
+        return dest;
+        
+    asm volatile(
+        "1:                         \n"
+        "ldrb x0, [%[src],  %[l]]   \n"
+        "strb x0, [%[dest], %[l]]   \n"
+        "sub  %[l], %[l], %0        \n"
+        "cbnz  %[l], 1b             \n"
+        ::
+        "I"(1),
+        [src]  "r"(dest),
+        [dest] "r"(src),
+        [l]    "r"(num)
+        : "x0" "x1"
+    );
+
+    return dest;
+}
+
+void*
+memset(void* ptr, int value, unsigned long num)
+{
+    asm volatile(
+        "1:                             \n"
+        "strb %[val], [%[dest], %[l]]   \n"
+        "sub  %[l], %[l], %0            \n"
+        "cbnz %[l], 1b                  \n"
+        ::
+        "I"(1),
+        [val]  "r"(value),
+        [dest] "r"(ptr),
+        [l]    "r"(num)
+        : "x1"
+    );
+
+    return ptr;
+}
+
+unsigned long
+strlen(const char* str)
+{
+    unsigned long register _c asm("x0");
+
+    _c = 0;
+    asm volatile(
+        "1:                     \n"
+        "ldrb x1, [%[ptr], %0]  \n"
+        "add  %0, %0, %1        \n"
+        "cbnz %0, 1b            \n"
+        :
+        "=r"(_c)
+        :
+        "I"(1),
+        [ptr]  "r"(str)
+        : "x1"
+    );
+
+    return _c;
+}
+
+unsigned long
+strnlen(const char* str, unsigned long max_len)
+{
+    unsigned long register _c asm("x0");
+
+    _c = 0;
+    asm volatile(
+        "1:                     \n"
+        "ldrb x1, [%[ptr], %0]  \n"
+        "add  %0, %0, %1        \n"
+        "sub  x2, %[len], %0    \n"
+        "ands x2, x2, x1        \n"
+        "bne  1b                \n"
+        :
+        "=r"(_c)
+        :
+        "I"(1),
+        [ptr]  "r"(str),
+        [len]  "r"(max_len)
+        : "x1", "x2"
+    );
+
+    return _c;
+}
\ No newline at end of file