refactoring fixes

runtime/io/vx_io.s

@@ -0,0 +1,33 @@
+
+
+.type vx_print_str, @function
+.global vx_print_str
+vx_print_str:
+    addi sp, sp, -12
+    sw   ra, 0(sp)
+    sw   a1, 4(sp)
+bl:
+    lbu  a1,0(a0)
+    beqz a1,be
+    jal  vx_printc
+    addi a0, a0, 1
+    j bl
+be:
+    lw   ra, 0(sp)
+    lw   a1, 4(sp)
+    addi sp, sp, 12
+    ret
+
+
+.type vx_printc, @function
+.global vx_printc
+vx_printc:
+    la t0, print_addr
+    lw t0, 0(t0)
+    sw a1, 0(t0)
+    ret
+
+.section .data
+print_addr:
+    .word 0x00010000 
+