[all-commits] [llvm/llvm-project] ff9379: [NFC] Remove waymarking because it improves perfor...

[Ralender via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: ff9379f4b2d7ebcb8dee94df47dc43c3388f22bf
      https://github.com/llvm/llvm-project/commit/ff9379f4b2d7ebcb8dee94df47dc43c3388f22bf
  Author: Tyker <tyker1 at outlook.com>
  Date:   2020-04-17 (Fri, 17 Apr 2020)

  Changed paths:
    M llvm/docs/ProgrammersManual.rst
    M llvm/include/llvm/Analysis/MemorySSA.h
    M llvm/include/llvm/IR/Instructions.h
    M llvm/include/llvm/IR/Use.h
    M llvm/include/llvm/IR/Value.h
    M llvm/lib/IR/Use.cpp
    M llvm/lib/IR/User.cpp
    M llvm/unittests/IR/CMakeLists.txt
    R llvm/unittests/IR/WaymarkTest.cpp

  Log Message:
  -----------
  [NFC] Remove waymarking because it improves performances

Summary:
This patch remove waymarking and replaces it with storing a pointer to the User in the Use.
here are the results on the measurements for the CTMark tests of the test suite.
```
Metric: instructions_count

Program                                                      baseline      patched       diff
 test-suite :: CTMark/ClamAV/clamscan.test                    72557942065   71733653521  -1.1%
 test-suite :: CTMark/sqlite3/sqlite3.test                    76281422939   75484840636  -1.0%
 test-suite :: CTMark/consumer-typeset/consumer-typeset.test  51364676366   50862185614  -1.0%
 test-suite :: CTMark/SPASS/SPASS.test                        60476106505   59908437767  -0.9%
 test-suite :: CTMark/tramp3d-v4/tramp3d-v4.test              112578442329  111725050856 -0.8%
 test-suite :: CTMark/mafft/pairlocalalign.test               50846133013   50473644539  -0.7%
 test-suite :: CTMark/kimwitu++/kc.test                       54692641250   54349070299  -0.6%
 test-suite :: CTMark/7zip/7zip-benchmark.test                182216614747  181216091230 -0.5%
 test-suite :: CTMark/Bullet/bullet.test                      123459210616  122905866767 -0.4%
 Geomean difference                                                                      -0.8%

Metric: peak_memory_use

Program                                                      baseline  patched   diff
 test-suite :: CTMark/tramp3d-v4/tramp3d-v4.test              326864    338524    3.6%
 test-suite :: CTMark/sqlite3/sqlite3.test                    216412    221240    2.2%
 test-suite :: CTMark/7zip/7zip-benchmark.test                11808284  12022604  1.8%
 test-suite :: CTMark/Bullet/bullet.test                      6831752   6945988   1.7%
 test-suite :: CTMark/SPASS/SPASS.test                        2682552   2721820   1.5%
 test-suite :: CTMark/ClamAV/clamscan.test                    5037256   5107936   1.4%
 test-suite :: CTMark/consumer-typeset/consumer-typeset.test  2752728   2790768   1.4%
 test-suite :: CTMark/mafft/pairlocalalign.test               1517676   1537244   1.3%
 test-suite :: CTMark/kimwitu++/kc.test                       1090748   1103448   1.2%
 Geomean difference                                                               1.8%

Metric: compile_time

Program                                                      baseline patched diff
 test-suite :: CTMark/consumer-typeset/consumer-typeset.test  14.71    14.38  -2.2%
 test-suite :: CTMark/sqlite3/sqlite3.test                    23.18    22.73  -2.0%
 test-suite :: CTMark/7zip/7zip-benchmark.test                57.96    56.99  -1.7%
 test-suite :: CTMark/ClamAV/clamscan.test                    20.75    20.49  -1.2%
 test-suite :: CTMark/kimwitu++/kc.test                       18.35    18.15  -1.1%
 test-suite :: CTMark/SPASS/SPASS.test                        18.72    18.57  -0.8%
 test-suite :: CTMark/mafft/pairlocalalign.test               14.09    14.00  -0.6%
 test-suite :: CTMark/Bullet/bullet.test                      37.38    37.19  -0.5%
 test-suite :: CTMark/tramp3d-v4/tramp3d-v4.test              33.81    33.76  -0.2%
 Geomean difference                                                           -1.1%
```

i believe that it is worth trading +1.8% peak memory use for -1.1% compile time.
also this patch removes waymarking which simplifies the Use and User classes.

Reviewers: nikic, lattner

Reviewed By: lattner

Subscribers: russell.gallop, foad, ggreif, rriddle, ekatz, fhahn, lebedev.ri, mgorny, hiraditya, george.burgess.iv, asbirlea, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D77144