9 Commits

Author SHA1 Message Date
Russell Gallop
12173bc1d5 Fix time-trace breaking flame graph assumptions
-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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@371039 91177308-0d34-0410-b5e6-96231b3b80d8
2019-09-05 09:26:04 +00:00
Anton Afanasyev
e104086ec9 [Support][Time profiler] Make FE codegen blocks to be inside frontend blocks
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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@369308 91177308-0d34-0410-b5e6-96231b3b80d8
2019-08-19 22:58:26 +00:00
Anton Afanasyev
1d7873cdea [Support] Fix -ftime-trace-granularity option
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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@366911 91177308-0d34-0410-b5e6-96231b3b80d8
2019-07-24 14:55:40 +00:00
Sam McCall
2802669519 [Support] Add JSON streaming output API, faster where the heavy value types aren't needed.
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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@359186 91177308-0d34-0410-b5e6-96231b3b80d8
2019-04-25 12:51:42 +00:00
Anton Afanasyev
e7738cac23 Time profiler: optimize json output time
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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@358522 91177308-0d34-0410-b5e6-96231b3b80d8
2019-04-16 20:36:56 +00:00
Anton Afanasyev
52536b57c4 Use native llvm JSON library for time profiler output
Summary: Replace plain json text output with llvm JSON library wrapper using.

Reviewers: takuto.ikuta, lebedev.ri

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60609

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@358476 91177308-0d34-0410-b5e6-96231b3b80d8
2019-04-16 06:35:07 +00:00
Anton Afanasyev
d601c8128b Time profiler: small fixes and optimizations
Summary: Fixes from Roman's review here: https://reviews.llvm.org/D58675#1465336

Reviewers: lebedev.ri

Subscribers: hiraditya, mgrang, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D60663

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@358448 91177308-0d34-0410-b5e6-96231b3b80d8
2019-04-15 21:02:47 +00:00
Anton Afanasyev
73f3377562 Improve hashing for time profiler
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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@357998 91177308-0d34-0410-b5e6-96231b3b80d8
2019-04-09 12:18:44 +00:00
Anton Afanasyev
cc6227998a Adds -ftime-trace option to clang that produces Chrome chrome://tracing compatible JSON profiling output dumps.
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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@357340 91177308-0d34-0410-b5e6-96231b3b80d8
2019-03-30 08:42:48 +00:00