Tools: added CPUInfo sketch

this shows the approximate cost of a wide range of common operations,
and the sizes of most data types

Tools/CPUInfo/CPUInfo.pde

@@ -0,0 +1,122 @@
+/// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: t -*-
+
+/*
+  test CPU speed
+  Andrew Tridgell September 2011
+*/
+
+#include <math.h>
+#include <FastSerial.h>
+
+FastSerialPort0(Serial);
+
+#define SERIAL0_BAUD 115200
+
+void setup() {
+	Serial.begin(SERIAL0_BAUD, 128, 128);
+}
+
+static void show_sizes(void)
+{
+	Serial.println("Type sizes:");
+	Serial.printf("char      : %d\n", sizeof(char));
+	Serial.printf("short     : %d\n", sizeof(short));
+	Serial.printf("int       : %d\n", sizeof(int));
+	Serial.printf("long      : %d\n", sizeof(long));
+	Serial.printf("long long : %d\n", sizeof(long long));
+	Serial.printf("bool      : %d\n", sizeof(bool));
+	Serial.printf("void*     : %d\n", sizeof(void *));
+}
+
+#define TENTIMES(x) do { x; x; x; x; x; x; x; x; x; x; } while (0)
+#define FIFTYTIMES(x) do { TENTIMES(x); TENTIMES(x); TENTIMES(x); TENTIMES(x); TENTIMES(x); } while (0)
+
+#define TIMEIT(name, op, count) do { \
+	uint32_t us_end, us_start; \
+	us_start = micros(); \
+	for (uint8_t i=0; i<count; i++) { \
+		FIFTYTIMES(op);				\
+	} \
+	us_end = micros(); \
+	Serial.printf("%-10s %7.2f usec/call\n", name, double(us_end-us_start)/(count*50.0)); \
+} while (0)
+
+volatile float v_f = 1.0;
+volatile float v_out;
+volatile double v_d = 1.0;
+volatile double v_out_d;
+volatile uint32_t v_32 = 1;
+volatile uint32_t v_out_32 = 1;
+volatile uint16_t v_16 = 1;
+volatile uint16_t v_out_16 = 1;
+volatile uint8_t v_8 = 1;
+volatile uint8_t v_out_8 = 1;
+volatile uint8_t mbuf1[128], mbuf2[128];
+
+static void show_timings(void)
+{
+
+	v_f = 1+(micros() % 5);
+	v_out = 1+(micros() % 3);
+
+	v_32 = 1+(micros() % 5);
+	v_out_32 = 1+(micros() % 3);
+
+	v_16 = 1+(micros() % 5);
+	v_out_16 = 1+(micros() % 3);
+
+	v_8 = 1+(micros() % 5);
+	v_out_8 = 1+(micros() % 3);
+
+
+	Serial.println("Operation timings:");
+	Serial.println("Note: timings for some operations are very data dependent");
+
+	TIMEIT("nop", asm volatile("nop"::), 255);
+	TIMEIT("cli/sei", cli(); sei(), 255);
+
+	TIMEIT("micros()", micros(), 200);
+	TIMEIT("millis()", millis(), 200);
+
+	TIMEIT("fadd", v_out += v_f, 100);
+	TIMEIT("fsub", v_out -= v_f, 100);
+	TIMEIT("fmul", v_out *= v_f, 100);
+	TIMEIT("fdiv", v_out /= v_f, 100);
+
+	TIMEIT("dadd", v_out_d += v_d, 100);
+	TIMEIT("dsub", v_out_d -= v_d, 100);
+	TIMEIT("dmul", v_out_d *= v_d, 100);
+	TIMEIT("ddiv", v_out_d /= v_d, 100);
+
+	TIMEIT("sin()", v_out = sin(v_f), 20);
+	TIMEIT("cos()", v_out = cos(v_f), 20);
+	TIMEIT("tan()", v_out = tan(v_f), 20);
+
+	TIMEIT("iadd8", v_out_8 += v_8, 100);
+	TIMEIT("isub8", v_out_8 -= v_8, 100);
+	TIMEIT("imul8", v_out_8 *= v_8, 100);
+	TIMEIT("idiv8", v_out_8 /= v_8, 100);
+
+	TIMEIT("iadd16", v_out_16 += v_16, 100);
+	TIMEIT("isub16", v_out_16 -= v_16, 100);
+	TIMEIT("imul16", v_out_16 *= v_16, 100);
+	TIMEIT("idiv16", v_out_16 /= v_16, 100);
+
+	TIMEIT("iadd32", v_out_32 += v_32, 100);
+	TIMEIT("isub32", v_out_32 -= v_32, 100);
+	TIMEIT("imul32", v_out_32 *= v_32, 100);
+	TIMEIT("idiv32", v_out_32 /= v_32, 100);
+
+	TIMEIT("memcpy128", memcpy((void*)mbuf1, (const void *)mbuf2, sizeof(mbuf1)), 20);
+	TIMEIT("memset128", memset((void*)mbuf1, 1, sizeof(mbuf1)), 20);
+	TIMEIT("delay(1)", delay(1), 5);
+}
+
+void loop()
+{
+	show_sizes();
+	Serial.println("");
+	show_timings();
+	Serial.println("");
+	delay(3000);
+}

Tools/CPUInfo/Makefile

@@ -0,0 +1,4 @@
+#
+# Trivial makefile for building APM
+#
+include ../../libraries/AP_Common/Arduino.mk