From 058ceda6a0e955539d4439fc8fcf53ebf2787331 Mon Sep 17 00:00:00 2001
From: Clifford Wolf <clifford@clifford.at>
Date: Fri, 22 Nov 2013 14:08:10 +0100
Subject: [PATCH] Added more performance measurement infrastructure

---
 Makefile     |  4 ++--
 kernel/log.h | 41 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 43 insertions(+), 2 deletions(-)

diff --git a/Makefile b/Makefile
index 3551723fd..06466fda5 100644
--- a/Makefile
+++ b/Makefile
@@ -20,7 +20,7 @@ all: top-all
 
 CXXFLAGS = -Wall -Wextra -ggdb -I"$(shell pwd)" -MD -D_YOSYS_ -fPIC
 LDFLAGS = -rdynamic
-LDLIBS = -lstdc++ -lreadline -lm -ldl
+LDLIBS = -lstdc++ -lreadline -lm -ldl -lrt
 QMAKE = qmake-qt4
 
 YOSYS_VER := 0.0.x
@@ -155,7 +155,7 @@ config-release: clean
 	echo 'CONFIG := release' > Makefile.conf
 
 config-gprof: clean
-	echo 'CONFIG := release' > Makefile.conf
+	echo 'CONFIG := gcc-debug' > Makefile.conf
 	echo 'ENABLE_GPROF := 1' >> Makefile.conf
 
 config-sudo:
diff --git a/kernel/log.h b/kernel/log.h
index dbfb6103e..d88dda889 100644
--- a/kernel/log.h
+++ b/kernel/log.h
@@ -22,6 +22,7 @@
 
 #include "kernel/rtlil.h"
 #include <stdio.h>
+#include <time.h>
 #include <vector>
 
 extern std::vector<FILE*> log_files;
@@ -52,4 +53,44 @@ const char *log_signal(const RTLIL::SigSpec &sig, bool autoint = true);
 #define log_abort() log_error("Abort in %s:%d.\n", __FILE__, __LINE__)
 #define log_assert(_assert_expr_) do { if (_assert_expr_) break; log_error("Assert `%s' failed in %s:%d.\n", #_assert_expr_, __FILE__, __LINE__); } while (0)
 
+// simple timer for performance measurements
+// toggle the '#if 1' to get a baseline for the perormance penalty added by the measurement
+struct PerformanceTimer
+{
+#if 1
+	int64_t total_ns;
+
+	PerformanceTimer() {
+		total_ns = 0;
+	}
+
+	static int64_t query() {
+		struct timespec ts;
+		clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &ts);
+		return int64_t(ts.tv_sec)*1000000000 + ts.tv_nsec;
+	}
+
+	void reset() {
+		total_ns = 0;
+	}
+
+	void add() {
+		total_ns += query();
+	}
+
+	void sub() {
+		total_ns -= query();
+	}
+
+	float sec() const {
+		return total_ns * 1e-9;
+	}
+#else
+	void reset() { }
+	void add() { }
+	void sub() { }
+	float sec() const { return 0; }
+#endif
+};
+
 #endif
-- 
2.30.2