sceKernelTryLockLwMutex_600 reverse

// Kernel_Library_37431849
// ptr[0] count
// ptr[1] lock_id
// ptr[2] flags
// ptr[4] id
s32 sceKernelTryLockLwMutex_600(s32 *ptr, u32 count)
{
    s32 tmp0;
    s32 tmp1;
    s32 tmp2;

    if (g_2bc0 == NULL) {
        // 0x80020064
        return SCE_ERROR_KERNEL_CANNOT_BE_CALLED_FROM_INTERRUPT;
    }

    if (count <= 0) {
        // 0x800201BD
        return SCE_ERROR_KERNEL_ILLEGAL_COUNT;
    }

    if (ptr[4] < 0) {
        // 0x800201CA
        return SCE_ERROR_KERNEL_LWMUTEX_NOT_FOUND;
    }

    if (ptr[1] == g_2bc0[48]) { // loc_00000340
        if (!((ptr[2] >> 9) & 1)) {
            // 0x800201CF
            return SCE_ERROR_KERNEL_LWMUTEX_RECURSIVE_NOT_ALLOWED;
        }

        if (ptr[0] + count < 0) {
            // 0x800201CD
            return SCE_ERROR_KERNEL_LWMUTEX_LOCK_OVERFLOW;
        }

        ptr[0] += count;

        return SCE_ERROR_OK;
    }

    if (ptr[1] != 0) {
        // 0x800201CB
        return SCE_ERROR_KERNEL_LWMUTEX_LOCKED;
    }

    if (((ptr[2] >> 9) & 1)) {
        tmp0 = 0;
    } else {
        tmp0 = count ^ 1;
    }

    if (tmp0) {
        // 0x800201BD
        return SCE_ERROR_KERNEL_ILLEGAL_COUNT;
    }

    do {
        /* begin atomic RMW */
        asm __volatile__(
            "ll %0, (%1)"
            : "=r" (tmp1)
            : "r" (&ptr[1])
        );

        if (tmp1) {
            // 0x800201CB
            return SCE_ERROR_KERNEL_LWMUTEX_LOCKED;
        }

        tmp2 = g_2bc0[48];

        /* end atomic RMW */
        /* if an atomic update as occured, %0 will be set to true */
        asm __volatile__(
            "sc %0, (%1)"
            : "=r" (tmp2)
            : "r" (&ptr[1])
        );
    } while (!tmp2);

    ptr[0] = count;

    return SCE_ERROR_OK;
}