From bdf3924fc78d0495b241e2202a9633cded6aca45 Mon Sep 17 00:00:00 2001
From: Jean-Marc Lasgouttes <lasgouttes@lyx.org>
Date: Sun, 17 Mar 2019 13:57:44 +0100
Subject: [PATCH] Update poor man's profiler to use C++11 std::chrono

This is more portable, and the old code prevented in windows to use
instrument several classes at the same time (several .obj files,
actually).

No new feature here, bu the code is nicely slower. It might be less
efficient, I am not really at ease with how std::chrono works.
---
 src/support/pmprof.h | 79 ++++++++++++++------------------------------
 1 file changed, 25 insertions(+), 54 deletions(-)

diff --git a/src/support/pmprof.h b/src/support/pmprof.h
index 8f91125f54..fb926708f8 100644
--- a/src/support/pmprof.h
+++ b/src/support/pmprof.h
@@ -112,52 +112,30 @@
 
 #else
 
-#ifdef _WIN32
-#include <windows.h>
-#else
-#include <sys/time.h>
-#endif
-
+#include <chrono>
 #include <iomanip>
 #include <iostream>
 
 
-#if defined(__GNUG__) && defined(_GLIBCXX_DEBUG)
-#error Profiling is not usable when run-time debugging is in effect
-#endif
-
-#ifdef _WIN32
-/* This function does not really returns the "time of day",
- * but it will suffice to evaluate elapsed times.
- */
-int gettimeofday(struct timeval * tv, struct timezone * /*tz*/)
-{
-	LARGE_INTEGER frequency, t;
-	QueryPerformanceFrequency(&frequency);
-	QueryPerformanceCounter(&t);
-
-	tv->tv_sec = long(t.QuadPart / frequency.QuadPart);
-	tv->tv_usec = long((1000000.0 * (t.QuadPart % frequency.QuadPart)) / frequency.QuadPart);
-	return 0;
-}
-
-#endif // _WIN32
+//#if defined(__GNUG__) && defined(_GLIBCXX_DEBUG)
+//#error Profiling is not usable when run-time debugging is in effect
+//#endif
 
 namespace {
 
-void dumpTime(long long value)
+void dumpTime(std::chrono::duration<double> value)
 {
+	double const val = value.count();
 	std::cerr << std::fixed << std::setprecision(2);
-	if (value >= 1000000)
-		std::cerr << value / 1000000 << "sec";
-	else if (value >= 1000)
-		std::cerr << value / 1000 << "msec";
+	if (val >= 1.0)
+	 	std::cerr << val << " s";
+	else if (val >= 0.001)
+		std::cerr << val * 1000 << " ms";
 	else
-		std::cerr << value << "usec";
+	 	std::cerr << val * 1000000 << " us";
 }
 
-void dump(long long sec, long long usec, unsigned long long count) {
-	double const total = sec * 1000000 + usec;
+void dump(std::chrono::duration<double> total, unsigned long long count) {
 	dumpTime(total / count);
 	std::cerr << ", count=" << count
 			  << ", total=";
@@ -176,44 +154,39 @@ void dump(long long sec, long long usec, unsigned long long count) {
 
 class PMProfStat {
 public:
-	PMProfStat(char const * name) : name_(name), sec_(0), usec_(0), count_(0),
-                                    miss_sec_(0), miss_usec_(0), miss_count_(0) {}
+	PMProfStat(char const * name) : name_(name), count_(0), miss_count_(0) {}
 
 	~PMProfStat() {
 		if (count_>0) {
 			if (miss_count_ == 0) {
 				std::cerr << "#pmprof# " << name_ << ": ";
-				dump(sec_, usec_, count_);
+				dump(dur_, count_);
 			}
 			else {
 				std::cerr << "#pmprof# " << name_ << ": ";
-				dump(sec_ + miss_sec_, usec_ + miss_usec_, count_ + miss_count_);
+				dump(dur_ + miss_dur_, count_ + miss_count_);
 				std::cerr << "   hit: " << 100 * count_ / (count_ + miss_count_) << "%, ";
-				dump(sec_, usec_, count_);
+				dump(dur_, count_);
 				std::cerr << "  miss: " << 100 * miss_count_ / (count_ + miss_count_) << "%, ";
-				dump(miss_sec_, miss_usec_, miss_count_);
+				dump(miss_dur_, miss_count_);
 			}
 		}
 	}
 
-	void add(const long long s, const long long u, const bool hit) {
+	void add(std::chrono::duration<double> d, const bool hit) {
 		if (hit) {
-			sec_ += s;
-			usec_ += u;
+			dur_ += d;
 			count_++;
 		} else {
-			miss_sec_ += s;
-			miss_usec_ += u;
+			miss_dur_ += d;
 			miss_count_++;
 		}
 	}
 
 private:
 	char const * name_;
-	long long sec_, usec_;
-	unsigned long long count_;
-	long long miss_sec_, miss_usec_;
-	unsigned long long miss_count_;
+	std::chrono::duration<double> dur_, miss_dur_;
+	unsigned long long count_, miss_count_;
 };
 
 
@@ -226,19 +199,17 @@ class PMProfInstance {
 public:
 	PMProfInstance(PMProfStat * stat) : hit(true), stat_(stat)
 	{
-		gettimeofday(&before_, 0);
+		before_ = std::chrono::system_clock::now();
 	}
 
 	~PMProfInstance() {
-		gettimeofday(&after_, 0);
-		stat_->add(after_.tv_sec - before_.tv_sec,
-		           after_.tv_usec - before_.tv_usec, hit);
+		stat_->add(std::chrono::system_clock::now() - before_, hit);
 	}
 
 	bool hit;
 
 private:
-	timeval before_, after_;
+	std::chrono::system_clock::time_point before_;
 	PMProfStat * stat_;
 };
 
-- 
2.39.2