Revert "generic-tracing: fix lossage of first event"

This reverts commit 036e340bd9.

Problems with this one were:
 -  Broken event timings.  m_prevtime wasn't reset to m_curtime in
    TracingPlugin::handleSingleIP(), resulting in a large deltatime
    being recorded for the second event, too.  This effectively
    doubled the experiment's start time.
 -  Code repetition (copy/pasted for special handling of first event),
    making planned changes (advanced tracing for IP events) more
    difficult.
 -  Unnecessary additional tracing-plugin interface method.

Change-Id: I4b74d1a3f4563aabe6626399f9b30a2171b4c285

src/experiments/generic-tracing/experiment.cc

@@ -209,10 +209,6 @@ bool GenericTracing::run()
 	// this must be done *after* configuring the plugin:
 	simulator.addFlow(&tp);
 
-    // In order to not loose the IP event at the beginning of the
-    // trace, we have to handle the IP event manually
-    tp.handleSingleIP(l_start_symbol);
-
 	////////////////////////////////////////////////////////////////
 	// STEP 2: continue to the save point, and save state
 	if (start_symbol != save_symbol) {

src/plugins/tracing/TracingPlugin.cc

@@ -1,7 +1,6 @@
 #include <iostream>
 #include <assert.h>
 
-#include "sal/SALConfig.hpp"
 #include "sal/SALInst.hpp"
 #include "sal/Register.hpp"
 #include "sal/Memory.hpp"
@@ -11,34 +10,6 @@
 using namespace std;
 using namespace fail;
 
-void TracingPlugin::handleSingleIP(const BPListener &bp) {
-	address_t ip = bp.getTriggerInstructionPointer();
-	if (m_ipMap && !m_ipMap->isMatching(ip)) {
-		return;
-	}
-
-	m_curtime = simulator.getTimerTicks();
-	simtime_diff_t deltatime = m_curtime - m_prevtime;
-
-	if (m_os)
-		*m_os << "[Tracing] IP " << hex << ip << "\n";
-
-	if (m_protoStreamFile) {
-		Trace_Event e;
-		e.set_ip(ip);
-		// only store deltas != 0
-		if (deltatime != 0) {
-			e.set_time_delta(deltatime);
-		}
-		if (!ps) {
-			ps = new ProtoOStream (m_protoStreamFile);
-		}
-
-		ps->writeMessage(&e);
-	}
-}
-
-
 bool TracingPlugin::run()
 {
 	MemoryManager& mm = simulator.getMemoryManager();
@@ -62,13 +33,14 @@ bool TracingPlugin::run()
 
 	// the first event gets an absolute time stamp, all others a delta to their
 	// predecessor
+	simtime_t prevtime = 0, curtime;
 	simtime_diff_t deltatime;
 
 	while (true) {
 		ev = simulator.resume();
 
-		m_curtime = simulator.getTimerTicks();
+		curtime = simulator.getTimerTicks();
-		deltatime = m_curtime - m_prevtime;
+		deltatime = curtime - prevtime;
 
 		if (ev == &ev_step) {
 			simulator.addListener(&ev_step);
@@ -150,7 +122,7 @@ bool TracingPlugin::run()
 
 		// do this only if the last delta was written
 		// (no, e.g., memory map mismatch)
-		m_prevtime = m_curtime;
+		prevtime = curtime;
 	}
 
 	return true;

src/plugins/tracing/TracingPlugin.hpp

@@ -7,8 +7,6 @@
 #include "util/ProtoStream.hpp"
 #include "efw/ExperimentFlow.hpp"
 #include "config/FailConfig.hpp"
-#include "sal/Listener.hpp"
-
 
 #include "TracePlugin.pb.h"
 
@@ -50,14 +48,10 @@ private:
 	std::ostream *m_os; //!< ostream to write human-readable trace into
 	fail::ProtoOStream *ps;
 
-	fail::simtime_t m_prevtime;
-	fail::simtime_t m_curtime;
-
 public:
 	TracingPlugin(bool full_trace = false)
 	 : m_memMap(0), m_ipMap(0), m_memonly(false), m_iponly(false),
-	   m_full_trace(full_trace), m_protoStreamFile(0), m_os(0),
+	   m_full_trace(full_trace), m_protoStreamFile(0), m_os(0) { }
-	   m_prevtime(0) { }
 	bool run();
 	/**
 	 * Restricts tracing to memory addresses listed in this MemoryMap.	An
@@ -94,13 +88,6 @@ public:
 	 * ProtoStream file to trace into (trace.proto instance)
 	 */
 	void setTraceFile(std::ostream *os) { m_protoStreamFile = os; }
-
-	/**
-	 * Handles a single IP event. This is important for starting the
-	 * tracing process after triggering a breakpoint. Just pass on the
-	 * breakpoint
-	 */
-	void handleSingleIP(const fail::BPListener &bp);
 };
 
 #endif // __TRACING_PLUGIN_HPP__