From: Matt Mullins <mmullins@mmlx.us>
Date: Sun, 23 Dec 2012 03:49:41 +0000 (-0800)
Subject: Refactor spin loops, to prepare for global -O3
X-Git-Url: http://git.mmlx.us/?a=commitdiff_plain;h=91e2321901fb59462d71a5d30afbfe1306a3aba1;p=stellaris%2Fled_blink.git

Refactor spin loops, to prepare for global -O3
---

diff --git a/led_blink.c b/led_blink.c
index 9b0f47b..7d25e4e 100644
--- 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; }
+}