Move global state in timevar.c to a new "timer" class

gcc/ChangeLog:
	* timevar.c (timevar_enable): Delete in favor of...
	(g_timer): New global.
	(struct timevar_def): Move to timevar.h inside class timer.
	(struct timevar_stack_def): Likewise.
	(timevars): Delete global in favor of field "m_timevars" within
	class timer in timevar.h
	(stack): Likewise, in favor of field "m_stack".
	(unused_stack_instances): Likewise, in favor of field
	"m_unused_stack_instances".
	(start_time): Likewise, in favor of field "m_start_time".
	(get_time): Eliminate check for timevar_enable.
	(timer::timer): New function, built from part of timevar_init.
	(timevar_init): Rewrite idempotency test from using
	"timevar_enable" bool to using dynamic allocation of "g_timer".
	Move rest of implementation into timer's constructor.
	(timevar_push_1): Rename to...
	(timer::push): ...this, adding "m_" prefixes to variables that
	are now fields of timer.
	(timevar_pop_1): Likewise, rename to...
	(timer::pop): ...this, and add "m_" prefixes.
	(timevar_start): Replace test for "timevar_enable" with one for
	"g_timer", and move bulk of implementation to...
	(timer::start): ...here, adding "m_" prefixes.
	(timevar_stop): Likewise, from here...
	(timer::stop): ...to here.
	(timevar_cond_start): Likewise, from here...
	(timer::cond_start): ...to here.
	(timevar_cond_stop): Likewise, from here...
	(timer::cond_stop): ...to here.
	(validate_phases): Rename to...
	(timer::validate_phases): ...this, and add "m_" prefixes.  Make
	locals "total" and "tv" const.
	(timevar_print): Rename to...
	(timer::print): ...this, and add "m_" prefixes.  Make locals
	"total" and "tv" const.  Eliminate test for timevar_enable.
	* timevar.h (timevar_enable): Eliminate.
	(g_timer): New declaration.
	(timevar_push_1): Eliminate.
	(timevar_pop_1): Eliminate.
	(timevar_print): Eliminate.
	(class timer): New class.
	(timevar_push): Rewrite to use g_timer.
	(timevar_pop): Likewise.
	* toplev.c (toplev::~toplev): Likewise.

From-SVN: r223092

gcc/ChangeLog

+2015-05-12  David Malcolm  <dmalcolm@redhat.com>
+
+	* timevar.c (timevar_enable): Delete in favor of...
+	(g_timer): New global.
+	(struct timevar_def): Move to timevar.h inside class timer.
+	(struct timevar_stack_def): Likewise.
+	(timevars): Delete global in favor of field "m_timevars" within
+	class timer in timevar.h
+	(stack): Likewise, in favor of field "m_stack".
+	(unused_stack_instances): Likewise, in favor of field
+	"m_unused_stack_instances".
+	(start_time): Likewise, in favor of field "m_start_time".
+	(get_time): Eliminate check for timevar_enable.
+	(timer::timer): New function, built from part of timevar_init.
+	(timevar_init): Rewrite idempotency test from using
+	"timevar_enable" bool to using dynamic allocation of "g_timer".
+	Move rest of implementation into timer's constructor.
+	(timevar_push_1): Rename to...
+	(timer::push): ...this, adding "m_" prefixes to variables that
+	are now fields of timer.
+	(timevar_pop_1): Likewise, rename to...
+	(timer::pop): ...this, and add "m_" prefixes.
+	(timevar_start): Replace test for "timevar_enable" with one for
+	"g_timer", and move bulk of implementation to...
+	(timer::start): ...here, adding "m_" prefixes.
+	(timevar_stop): Likewise, from here...
+	(timer::stop): ...to here.
+	(timevar_cond_start): Likewise, from here...
+	(timer::cond_start): ...to here.
+	(timevar_cond_stop): Likewise, from here...
+	(timer::cond_stop): ...to here.
+	(validate_phases): Rename to...
+	(timer::validate_phases): ...this, and add "m_" prefixes.  Make
+	locals "total" and "tv" const.
+	(timevar_print): Rename to...
+	(timer::print): ...this, and add "m_" prefixes.  Make locals
+	"total" and "tv" const.  Eliminate test for timevar_enable.
+	* timevar.h (timevar_enable): Eliminate.
+	(g_timer): New declaration.
+	(timevar_push_1): Eliminate.
+	(timevar_pop_1): Eliminate.
+	(timevar_print): Eliminate.
+	(class timer): New class.
+	(timevar_push): Rewrite to use g_timer.
+	(timevar_pop): Likewise.
+	* toplev.c (toplev::~toplev): Likewise.
+
 2015-05-12  Richard Earnshaw  <rearnsha@arm.com>
 
 	* arm-protos.h (arm_sched_autopref): Delete.

gcc/timevar.h

@@ -79,35 +79,118 @@ typedef enum
 timevar_id_t;
 #undef DEFTIMEVAR
 
-/* True if timevars should be used.  In GCC, this happens with
-   the -ftime-report flag.  */
-extern bool timevar_enable;
+/* A class to hold all state relating to timing.  */
+
+class timer;
+
+/* The singleton instance of timing state.
+
+   This is non-NULL if timevars should be used.  In GCC, this happens with
+   the -ftime-report flag.  Hence this is NULL for the common,
+   needs-to-be-fast case, with an early reject happening for this being
+   NULL.  */
+extern timer *g_timer;
 
 /* Total amount of memory allocated by garbage collector.  */
 extern size_t timevar_ggc_mem_total;
 
 extern void timevar_init (void);
-extern void timevar_push_1 (timevar_id_t);
-extern void timevar_pop_1 (timevar_id_t);
 extern void timevar_start (timevar_id_t);
 extern void timevar_stop (timevar_id_t);
 extern bool timevar_cond_start (timevar_id_t);
 extern void timevar_cond_stop (timevar_id_t, bool);
-extern void timevar_print (FILE *);
+
+/* The public (within GCC) interface for timing.  */
+
+class timer
+{
+ public:
+  timer ();
+  ~timer ();
+
+  void start (timevar_id_t tv);
+  void stop (timevar_id_t tv);
+  void push (timevar_id_t tv);
+  void pop (timevar_id_t tv);
+  bool cond_start (timevar_id_t tv);
+  void cond_stop (timevar_id_t tv);
+
+  void print (FILE *fp);
+
+ private:
+  /* Private member functions.  */
+  void validate_phases (FILE *fp) const;
+
+ private:
+
+  /* Private type: a timing variable.  */
+  struct timevar_def
+  {
+    /* Elapsed time for this variable.  */
+    struct timevar_time_def elapsed;
+
+    /* If this variable is timed independently of the timing stack,
+       using timevar_start, this contains the start time.  */
+    struct timevar_time_def start_time;
+
+    /* The name of this timing variable.  */
+    const char *name;
+
+    /* Nonzero if this timing variable is running as a standalone
+       timer.  */
+    unsigned standalone : 1;
+
+    /* Nonzero if this timing variable was ever started or pushed onto
+       the timing stack.  */
+    unsigned used : 1;
+  };
+
+  /* Private type: an element on the timing stack
+     Elapsed time is attributed to the topmost timing variable on the
+     stack.  */
+  struct timevar_stack_def
+  {
+    /* The timing variable at this stack level.  */
+    struct timevar_def *timevar;
+
+    /* The next lower timing variable context in the stack.  */
+    struct timevar_stack_def *next;
+  };
+
+ private:
+
+  /* Data members (all private).  */
+
+  /* Declared timing variables.  Constructed from the contents of
+     timevar.def.  */
+  timevar_def m_timevars[TIMEVAR_LAST];
+
+  /* The top of the timing stack.  */
+  timevar_stack_def *m_stack;
+
+  /* A list of unused (i.e. allocated and subsequently popped)
+     timevar_stack_def instances.  */
+  timevar_stack_def *m_unused_stack_instances;
+
+  /* The time at which the topmost element on the timing stack was
+     pushed.  Time elapsed since then is attributed to the topmost
+     element.  */
+  timevar_time_def m_start_time;
+};
 
 /* Provided for backward compatibility.  */
 static inline void
 timevar_push (timevar_id_t tv)
 {
-  if (timevar_enable)
-    timevar_push_1 (tv);
+  if (g_timer)
+    g_timer->push (tv);
 }
 
 static inline void
 timevar_pop (timevar_id_t tv)
 {
-  if (timevar_enable)
-    timevar_pop_1 (tv);
+  if (g_timer)
+    g_timer->pop (tv);
 }
 
 // This is a simple timevar wrapper class that pushes a timevar in its

gcc/toplev.c

@@ -2095,8 +2095,11 @@ toplev::toplev (bool use_TV_TOTAL, bool init_signals)
 
 toplev::~toplev ()
 {
-  timevar_stop (TV_TOTAL);
-  timevar_print (stderr);
+  if (g_timer)
+    {
+      g_timer->stop (TV_TOTAL);
+      g_timer->print (stderr);
+    }
 }
 
 void