PerformanceAwareProgramming/part2/listing_0091_switchable_profiler.cpp
2024-03-03 22:33:57 +11:00

143 lines
4.3 KiB
C++

/* ========================================================================
(C) Copyright 2023 by Molly Rocket, Inc., All Rights Reserved.
This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
arising from the use of this software.
Please see https://computerenhance.com for more information
======================================================================== */
/* ========================================================================
LISTING 91
======================================================================== */
#include "listing_0074_platform_metrics.cpp"
#ifndef PROFILER
#define PROFILER 0
#endif
#if PROFILER
struct profile_anchor
{
u64 TSCElapsedExclusive; // NOTE(casey): Does NOT include children
u64 TSCElapsedInclusive; // NOTE(casey): DOES include children
u64 HitCount;
char const *Label;
};
static profile_anchor GlobalProfilerAnchors[4096];
static u32 GlobalProfilerParent;
struct profile_block
{
profile_block(char const *Label_, u32 AnchorIndex_)
{
ParentIndex = GlobalProfilerParent;
AnchorIndex = AnchorIndex_;
Label = Label_;
profile_anchor *Anchor = GlobalProfilerAnchors + AnchorIndex;
OldTSCElapsedInclusive = Anchor->TSCElapsedInclusive;
GlobalProfilerParent = AnchorIndex;
StartTSC = ReadCPUTimer();
}
~profile_block(void)
{
u64 Elapsed = ReadCPUTimer() - StartTSC;
GlobalProfilerParent = ParentIndex;
profile_anchor *Parent = GlobalProfilerAnchors + ParentIndex;
profile_anchor *Anchor = GlobalProfilerAnchors + AnchorIndex;
Parent->TSCElapsedExclusive -= Elapsed;
Anchor->TSCElapsedExclusive += Elapsed;
Anchor->TSCElapsedInclusive = OldTSCElapsedInclusive + Elapsed;
++Anchor->HitCount;
/* NOTE(casey): This write happens every time solely because there is no
straightforward way in C++ to have the same ease-of-use. In a better programming
language, it would be simple to have the anchor points gathered and labeled at compile
time, and this repetative write would be eliminated. */
Anchor->Label = Label;
}
char const *Label;
u64 OldTSCElapsedInclusive;
u64 StartTSC;
u32 ParentIndex;
u32 AnchorIndex;
};
#define NameConcat2(A, B) A##B
#define NameConcat(A, B) NameConcat2(A, B)
#define TimeBlock(Name) profile_block NameConcat(Block, __LINE__)(Name, __COUNTER__ + 1);
#define ProfilerEndOfCompilationUnit static_assert(__COUNTER__ < ArrayCount(GlobalProfilerAnchors), "Number of profile points exceeds size of profiler::Anchors array")
static void PrintTimeElapsed(u64 TotalTSCElapsed, profile_anchor *Anchor)
{
f64 Percent = 100.0 * ((f64)Anchor->TSCElapsedExclusive / (f64)TotalTSCElapsed);
printf(" %s[%llu]: %llu (%.2f%%", Anchor->Label, Anchor->HitCount, Anchor->TSCElapsedExclusive, Percent);
if(Anchor->TSCElapsedInclusive != Anchor->TSCElapsedExclusive)
{
f64 PercentWithChildren = 100.0 * ((f64)Anchor->TSCElapsedInclusive / (f64)TotalTSCElapsed);
printf(", %.2f%% w/children", PercentWithChildren);
}
printf(")\n");
}
static void PrintAnchorData(u64 TotalCPUElapsed)
{
for(u32 AnchorIndex = 0; AnchorIndex < ArrayCount(GlobalProfilerAnchors); ++AnchorIndex)
{
profile_anchor *Anchor = GlobalProfilerAnchors + AnchorIndex;
if(Anchor->TSCElapsedInclusive)
{
PrintTimeElapsed(TotalCPUElapsed, Anchor);
}
}
}
#else
#define TimeBlock(...)
#define PrintAnchorData(...)
#define ProfilerEndOfCompilationUnit
#endif
struct profiler
{
u64 StartTSC;
u64 EndTSC;
};
static profiler GlobalProfiler;
#define TimeFunction TimeBlock(__func__)
static void BeginProfile(void)
{
GlobalProfiler.StartTSC = ReadCPUTimer();
}
static void EndAndPrintProfile()
{
GlobalProfiler.EndTSC = ReadCPUTimer();
u64 CPUFreq = EstimateCPUTimerFreq();
u64 TotalCPUElapsed = GlobalProfiler.EndTSC - GlobalProfiler.StartTSC;
if(CPUFreq)
{
printf("\nTotal time: %0.4fms (CPU freq %llu)\n", 1000.0 * (f64)TotalCPUElapsed / (f64)CPUFreq, CPUFreq);
}
PrintAnchorData(TotalCPUElapsed);
}