tests: add thread_float test app

tests/thread_float/Makefile

+APPLICATION = thread_float
+include ../Makefile.tests_common
+
+BOARD_INSUFFICIENT_MEMORY := airfy-beacon arduino-uno arduino-duemilanove \
+			     alliope-mini cc2650stk chronos maple-mini \
+                             mbed_lpc1768 microbit msb-430 msb-430h nrf51dongle \
+                             nrf6310 nucleo-f031k6 nucleo-f042k6 \
+                             opencm9-04 pca10000 pca10005 spark-core \
+                             stm32f0discovery weio yunjia-nrf51822
+
+USEMODULE += printf_float
+USEMODULE += xtimer
+
+#DISABLE_MODULE += cortexm_fpu
+
+include $(RIOTBASE)/Makefile.include

tests/thread_float/main.c

+/*
+ * Copyright (C) 2017 OTA keys S.A.
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @ingroup tests
+ * @{
+ *
+ * @file
+ * @brief Thread test application
+ *
+ * @author Vincent Dupont <vincent@otakeys.com>
+ *
+ * @}
+ */
+
+#include <stdio.h>
+
+#include "thread.h"
+#include "msg.h"
+#include "xtimer.h"
+#include "timex.h"
+
+static char t1_stack[THREAD_STACKSIZE_MAIN];
+static char t2_stack[THREAD_STACKSIZE_MAIN];
+static char t3_stack[THREAD_STACKSIZE_MAIN];
+
+static kernel_pid_t p1, p2, p3;
+
+static xtimer_t timer;
+#define OFFSET (10 * XTIMER_BACKOFF)
+
+static mutex_t lock = MUTEX_INIT;
+
+static void timer_cb(void *arg)
+{
+    (void) arg;
+
+    thread_yield();
+    xtimer_set(&timer, OFFSET);
+}
+
+static void *thread1(void *arg)
+{
+    (void) arg;
+
+    float f, init;
+
+    printf("THREAD %" PRIkernel_pid " start\n", thread_getpid());
+
+    init = 1.0 * thread_getpid();
+    f = init;
+
+    while (1) {
+        for (unsigned long i = 0; i < 10000ul; i++) {
+            f = f + 1.0 / f;
+        }
+        mutex_lock(&lock);
+        printf("T(%" PRIkernel_pid "): %f\n", thread_getpid(), (double)f);
+        mutex_unlock(&lock);
+        init += 1.0;
+        f = init;
+    }
+    return NULL;
+}
+
+static void *thread2(void *arg)
+{
+    (void) arg;
+
+    float f, init;
+
+    printf("THREAD %" PRIkernel_pid " start\n", thread_getpid());
+
+    init = 1.0 * thread_getpid();
+    f = init;
+
+    while (1) {
+        for (unsigned long i = 0; i < 100000ul; i++) {
+            f = f + 1.0 / f;
+        }
+        init += 1.0;
+        f = init;
+    }
+    return NULL;
+}
+
+int main(void)
+{
+    p1 = thread_create(t1_stack, sizeof(t1_stack), THREAD_PRIORITY_MAIN + 1,
+                       THREAD_CREATE_WOUT_YIELD | THREAD_CREATE_STACKTEST,
+                       thread1, NULL, "nr1");
+    p2 = thread_create(t2_stack, sizeof(t2_stack), THREAD_PRIORITY_MAIN + 1,
+                       THREAD_CREATE_WOUT_YIELD | THREAD_CREATE_STACKTEST,
+                       thread2, NULL, "nr2");
+    p3 = thread_create(t3_stack, sizeof(t3_stack), THREAD_PRIORITY_MAIN + 1,
+                       THREAD_CREATE_WOUT_YIELD | THREAD_CREATE_STACKTEST,
+                       thread1, NULL, "nr3");
+    puts("THREADS CREATED\n");
+
+
+    timer.callback = timer_cb;
+    xtimer_set(&timer, OFFSET);
+
+    return 0;
+}