js/src/devtools/vprof/readme.txt@6474c204b198 (annotated)
js/src/devtools/vprof/readme.txt
Wed, 31 Dec 2014 06:09:35 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Wed, 31 Dec 2014 06:09:35 +0100
- changeset 0
- 6474c204b198
- permissions
- -rw-r--r--
Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.
| michael@0 | 1 | # This Source Code Form is subject to the terms of the Mozilla Public |
| michael@0 | 2 | # License, v. 2.0. If a copy of the MPL was not distributed with this |
| michael@0 | 3 | # file, You can obtain one at http://mozilla.org/MPL/2.0/. |
| michael@0 | 4 | |
| michael@0 | 5 | The two files vprof.h and vprof.cpp implement a simple value-profiling mechanism. By including these two files in avmplus (or any other project), you can value profile data as you wish (currently integers). |
| michael@0 | 6 | |
| michael@0 | 7 | Usage: |
| michael@0 | 8 | #include "vprof.h" // in the source file you want to use it |
| michael@0 | 9 | |
| michael@0 | 10 | _vprof (value); |
| michael@0 | 11 | |
| michael@0 | 12 | At the end of the execution, for each probe you'll get the data associated with the probe, such as: |
| michael@0 | 13 | |
| michael@0 | 14 | File line avg [min : max] total count |
| michael@0 | 15 | ..\..\pcre\pcre_valid_utf8.cpp 182 50222.75916 [0 : 104947] 4036955604 80381 |
| michael@0 | 16 | |
| michael@0 | 17 | The probe is defined at line 182 of file pcre_vali_utf8.cpp. It was called 80381 times. The min value of the probe was 0 while its max was 10497 and its average was 50222.75916. The total sum of all values of the probe is 4036955604. Later, I plan to add more options on the spectrum of data among others. |
| michael@0 | 18 | |
| michael@0 | 19 | A few typical uses |
| michael@0 | 20 | ------------------ |
| michael@0 | 21 | |
| michael@0 | 22 | To see how many times a given function gets executed do: |
| michael@0 | 23 | |
| michael@0 | 24 | void f() |
| michael@0 | 25 | { |
| michael@0 | 26 | _vprof(1); |
| michael@0 | 27 | ... |
| michael@0 | 28 | } |
| michael@0 | 29 | |
| michael@0 | 30 | void f() |
| michael@0 | 31 | { |
| michael@0 | 32 | _vprof(1); |
| michael@0 | 33 | ... |
| michael@0 | 34 | if (...) { |
| michael@0 | 35 | _vprof(1); |
| michael@0 | 36 | ... |
| michael@0 | 37 | } else { |
| michael@0 | 38 | _vprof(1); |
| michael@0 | 39 | ... |
| michael@0 | 40 | } |
| michael@0 | 41 | } |
| michael@0 | 42 | |
| michael@0 | 43 | Here are a few examples of using the value-profiling utility: |
| michael@0 | 44 | |
| michael@0 | 45 | _vprof (e); |
| michael@0 | 46 | at the end of program execution, you'll get a dump of the source location of this probe, |
| michael@0 | 47 | its min, max, average, the total sum of all instances of e, and the total number of times this probe was called. |
| michael@0 | 48 | |
| michael@0 | 49 | _vprof (x > 0); |
| michael@0 | 50 | shows how many times and what percentage of the cases x was > 0, |
| michael@0 | 51 | that is the probablitiy that x > 0. |
| michael@0 | 52 | |
| michael@0 | 53 | _vprof (n % 2 == 0); |
| michael@0 | 54 | shows how many times n was an even number |
| michael@0 | 55 | as well as th probablitiy of n being an even number. |
| michael@0 | 56 | |
| michael@0 | 57 | _hprof (n, 4, 1000, 5000, 5001, 10000); |
| michael@0 | 58 | gives you the histogram of n over the given 4 bucket boundaries: |
| michael@0 | 59 | # cases < 1000 |
| michael@0 | 60 | # cases >= 1000 and < 5000 |
| michael@0 | 61 | # cases >= 5000 and < 5001 |
| michael@0 | 62 | # cases >= 5001 and < 10000 |
| michael@0 | 63 | # cases >= 10000 |
| michael@0 | 64 | |
| michael@0 | 65 | _nvprof ("event name", value); |
| michael@0 | 66 | all instances with the same name are merged |
| michael@0 | 67 | so, you can call _vprof with the same event name at difference places |
| michael@0 | 68 | |
| michael@0 | 69 | _vprof (e, myProbe); |
| michael@0 | 70 | value profile e and call myProbe (void* vprofID) at the profiling point. |
| michael@0 | 71 | inside the probe, the client has the predefined variables: |
| michael@0 | 72 | _VAL, _COUNT, _SUM, _MIN, _MAX, and the general purpose registers |
| michael@0 | 73 | _IVAR1, ..., IVAR4 general integer registrs |
| michael@0 | 74 | _I64VAR1, ..., I64VAR4 general integer64 registrs |
| michael@0 | 75 | _DVAR1, ..., _DVAR4 general double registers |
| michael@0 | 76 | _GENPTR a generic pointer that can be used by the client |
| michael@0 | 77 | the number of registers can be changed in vprof.h |
| michael@0 | 78 | |
| michael@0 | 79 | Named Events |
| michael@0 | 80 | ------------ |
| michael@0 | 81 | _nvprof ("event name", value); |
| michael@0 | 82 | all instances with the same name are merged |
| michael@0 | 83 | so, you can call _vprof with the same event name at difference places |
| michael@0 | 84 | |
| michael@0 | 85 | |
| michael@0 | 86 | Custom Probes |
| michael@0 | 87 | -------------- |
| michael@0 | 88 | You can call your own custom probe at the profiling point. |
| michael@0 | 89 | _vprof (v, myProbe); |
| michael@0 | 90 | value profile v and call myProbe (void* vprofID) at the profiling point |
| michael@0 | 91 | inside the probe, the client has the predefined variables: |
| michael@0 | 92 | _VAL, _COUNT, _SUM, _MIN, _MAX, and the general purpose registers |
| michael@0 | 93 | _IVAR1, ..., IVAR4 general integer registrs |
| michael@0 | 94 | _I64VAR1, ..., I64VAR4 general integer64 registrs |
| michael@0 | 95 | _DVAR1, ..., _DVAR4 general double registers |
| michael@0 | 96 | the number of registers can be changed in vprof.h |
| michael@0 | 97 | _GENPTR a generic pointer that can be used for almost anything |
