Refactor spin loops, to prepare for global -O3

diff --git a/led_blink.c b/led_blink.c
index 9b0f47b..7d25e4e 100644 (file)
--- a/led_blink.c
+++ b/led_blink.c
@@ -1,14 +1,15 @@
 #include "led_blink.h"
 #include <lm4f120h5qr.h>
 
+static void spin(int);
+
 __attribute__((isr))
 void main_isr() {
        // Enable Port F
        SYSCTL_RCGCGPIO_R = 0x20;
 
        // Wait for a few clocks to let GPIO module stabilize
-       for (int i = 0; i < 10; ++i) {
-       }
+       spin(10);
 
        // RGB pins (PF1, 2, 3) as outputs
        GPIO_PORTF_DIR_R = 0xE;
@@ -26,7 +27,10 @@ void main_isr() {
        for (;;) { 
                *(GPIO_PORTF_DATA_BITS_R + 0xC) ^= 0xC;
 
-               for (int j = 0; j < 1000000; ++j) {
-               }
+               spin(1000000);
        }
 }
+
+void spin(int cycles) {
+       while (cycles) { cycles -= 1; }
+}