Merge branch 'profiling'

1 files changed, 96 insertions, 0 deletions

diff --git a/libraries/libprof/profil.c b/libraries/libprof/profil.c
new file mode 100644
index 0000000..b0d8d55
--- /dev/null
+++ b/libraries/libprof/profil.c
@@ -0,0 +1,96 @@
+/* profil.c -- win32 profil.c equivalent
+
+   Copyright 1998, 1999, 2000, 2001, 2002 Red Hat, Inc.
+
+   This file is part of Cygwin.
+
+   This software is a copyrighted work licensed under the terms of the
+   Cygwin license.  Please consult the file "CYGWIN_LICENSE" for
+   details. */
+
+/*
+ * This file is taken from Cygwin distribution, adapted to be used for bare embedded targets.
+ */
+#include <stdio.h>
+#include <sys/types.h>
+#include <errno.h>
+#include <math.h>
+#include "profil.h"
+#include <string.h>
+
+#include "stm32f4xx_hal.h"      /* __get_MSP */
+
+/* global profinfo for profil() call */
+static struct profinfo prof = {
+  PROFILE_NOT_INIT, 0, 0, 0, 0
+};
+
+/* sample the current program counter */
+void profil_callback(void) {
+  if (prof.state == PROFILE_ON) {
+    /* The interrupt mechanism pushes xPSR, PC, LR, R12, and R3-R0 onto the
+     * stack, so PC is the 6th word from the top at that point. However, the
+     * normal function entry code pushes registers as well, so the stack
+     * offset right now depends on the call tree that got us here.
+     */
+    size_t pc = (size_t)((uint32_t *)__get_MSP())[6 + 6];
+    if (pc >= prof.lowpc && pc < prof.highpc) {
+      size_t idx = PROFIDX (pc, prof.lowpc, prof.scale);
+      prof.counter[idx]++;
+    }
+  }
+}
+
+/* Stop profiling to the profiling buffer pointed to by p. */
+static int profile_off (struct profinfo *p) {
+  p->state = PROFILE_OFF;
+  return 0;
+}
+
+/* Create a timer thread and pass it a pointer P to the profiling buffer. */
+static int profile_on (struct profinfo *p) {
+  p->state = PROFILE_ON;
+  return 0; /* ok */
+}
+
+/*
+ * start or stop profiling
+ *
+ * profiling goes into the SAMPLES buffer of size SIZE (which is treated
+ * as an array of unsigned shorts of size size/2)
+ *
+ * each bin represents a range of pc addresses from OFFSET.  The number
+ * of pc addresses in a bin depends on SCALE.  (A scale of 65536 maps
+ * each bin to two addresses, A scale of 32768 maps each bin to 4 addresses,
+ * a scale of 1 maps each bin to 128k address).  Scale may be 1 - 65536,
+ * or zero to turn off profiling
+ */
+int profile_ctl (struct profinfo *p, char *samples, size_t size, size_t offset, unsigned int scale) {
+  size_t maxbin;
+
+  if (scale > 65536) {
+    errno = EINVAL;
+    return -1;
+  }
+  profile_off(p);
+  if (scale) {
+    memset(samples, 0, size);
+    memset(p, 0, sizeof *p);
+    maxbin = size >> 1;
+    prof.counter = (unsigned short*)samples;
+    prof.lowpc = offset;
+    prof.highpc = PROFADDR(maxbin, offset, scale);
+    prof.scale = scale;
+    return profile_on(p);
+  }
+  return 0;
+}
+
+/* Equivalent to unix profil()
+   Every SLEEPTIME interval, the user's program counter (PC) is examined:
+   offset is subtracted and the result is multiplied by scale.
+   The word pointed to by this address is incremented. */
+int profil (char *samples, size_t size, size_t offset, unsigned int scale) {
+  return profile_ctl (&prof, samples, size, offset, scale);
+}
+