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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
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parentInitial commit. (diff)
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Adding upstream version 124.0.1.upstream/124.0.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
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+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+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).
+
+Usage:
+#include "vprof.h" // in the source file you want to use it
+
+_vprof (value);
+
+At the end of the execution, for each probe you'll get the data associated with the probe, such as:
+
+File line avg [min : max] total count
+..\..\pcre\pcre_valid_utf8.cpp 182 50222.75916 [0 : 104947] 4036955604 80381
+
+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.
+
+A few typical uses
+------------------
+
+To see how many times a given function gets executed do:
+
+void f()
+{
+ _vprof(1);
+ ...
+}
+
+void f()
+{
+ _vprof(1);
+ ...
+ if (...) {
+ _vprof(1);
+ ...
+ } else {
+ _vprof(1);
+ ...
+ }
+}
+
+Here are a few examples of using the value-profiling utility:
+
+ _vprof (e);
+ at the end of program execution, you'll get a dump of the source location of this probe,
+ its min, max, average, the total sum of all instances of e, and the total number of times this probe was called.
+
+ _vprof (x > 0);
+ shows how many times and what percentage of the cases x was > 0,
+ that is the probablitiy that x > 0.
+
+ _vprof (n % 2 == 0);
+ shows how many times n was an even number
+ as well as th probablitiy of n being an even number.
+
+ _hprof (n, 4, 1000, 5000, 5001, 10000);
+ gives you the histogram of n over the given 4 bucket boundaries:
+ # cases < 1000
+ # cases >= 1000 and < 5000
+ # cases >= 5000 and < 5001
+ # cases >= 5001 and < 10000
+ # cases >= 10000
+
+ _nvprof ("event name", value);
+ all instances with the same name are merged
+ so, you can call _vprof with the same event name at difference places
+
+ _vprof (e, myProbe);
+ value profile e and call myProbe (void* vprofID) at the profiling point.
+ inside the probe, the client has the predefined variables:
+ _VAL, _COUNT, _SUM, _MIN, _MAX, and the general purpose registers
+ _IVAR1, ..., IVAR4 general integer registrs
+ _I64VAR1, ..., I64VAR4 general integer64 registrs
+ _DVAR1, ..., _DVAR4 general double registers
+ _GENPTR a generic pointer that can be used by the client
+ the number of registers can be changed in vprof.h
+
+Named Events
+------------
+_nvprof ("event name", value);
+ all instances with the same name are merged
+ so, you can call _vprof with the same event name at difference places
+
+
+Custom Probes
+--------------
+You can call your own custom probe at the profiling point.
+_vprof (v, myProbe);
+ value profile v and call myProbe (void* vprofID) at the profiling point
+ inside the probe, the client has the predefined variables:
+ _VAL, _COUNT, _SUM, _MIN, _MAX, and the general purpose registers
+ _IVAR1, ..., IVAR4 general integer registrs
+ _I64VAR1, ..., I64VAR4 general integer64 registrs
+ _DVAR1, ..., _DVAR4 general double registers
+ the number of registers can be changed in vprof.h
+ _GENPTR a generic pointer that can be used for almost anything