-ftime-trace could break flame-graph assumptions on Windows, with an
inner scope overrunning outer scopes. This was due to the way that times
were truncated. Changed this so time_points for the flame-graph are
truncated instead of durations, preserving the relative order of event
starts and ends.
I have tried to retain the extra precision for the totals, which count
thousands or millions of events.
Added assert to check this property holds in future.
Fixes PR43043
Differential Revision: https://reviews.llvm.org/D66411
llvm-svn: 371039
Summary:
Add `Frontend` time trace entry to `HandleTranslationUnit()` function.
Add test to check all codegen blocks are inside frontend blocks.
Also, change `--time-trace-granularity` option a bit to make sure very small
time blocks are outputed to json-file when using `--time-trace-granularity=0`.
This fixes http://llvm.org/pr41969
Reviewers: russell.gallop, lebedev.ri, thakis
Reviewed By: russell.gallop
Subscribers: vsapsai, aras-p, lebedev.ri, hiraditya, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D63325
llvm-svn: 369308
Summary:
Move `-ftime-trace-granularity` option to frontend options. Without patch
this option is showed up in the help for any tool that links libSupport.
Reviewers: sammccall
Subscribers: hiraditya, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D65202
llvm-svn: 366911
Summary:
There's still a little bit of constant factor that could be trimmed (e.g.
more overloads to avoid round-tripping primitives through json::Value).
But this solves the memory scaling problem, and greatly improves the performance
constant factor, and the API should leave room for optimization if needed.
Adapt TimeProfiler to use it, eliminating almost all the performance regression
from r358476.
Performance test on my machine:
perf stat -r 5 ~/llvmbuild-opt/bin/clang++ -w -S -ftime-trace -mllvm -time-trace-granularity=0 spirit.cpp
Handcrafted JSON (HEAD=r358532 with r358476 reverted): 2480ms
json::Value (HEAD): 2757ms (+11%)
After this patch: 2520 ms (+1.6%)
Reviewers: anton-afanasyev, lebedev.ri
Subscribers: kristina, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60804
llvm-svn: 359186
Summary:
Use llvm::json::Array.reserve() to optimize json output time. Here is motivation:
https://reviews.llvm.org/D60609#1468941. In short: for the json array
with ~32K entries, pushing back each entry takes ~4% of whole time compared
to the method of preliminary memory reservation: (3995-3845)/3995 = 3.75%.
Reviewers: lebedev.ri
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60792
llvm-svn: 358522
Summary:
Use optimized hashing while writing time trace by join two hashes to one.
Used for -ftime-trace option.
Reviewers: rnk, takuto.ikuta
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60404
llvm-svn: 357998
This change adds hierarchical "time trace" profiling blocks that can be visualized in Chrome, in a "flame chart" style. Each profiling block can have a "detail" string that for example indicates the file being processed, template name being instantiated, function being optimized etc.
This is taken from GitHub PR: https://github.com/aras-p/llvm-project-20170507/pull/2
Patch by Aras Pranckevičius.
Differential Revision: https://reviews.llvm.org/D58675
llvm-svn: 357340
Russell Gallop