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LLVM-PROFDATA(1) LLVM LLVM-PROFDATA(1)
NAME
llvm-profdata - Profile data tool
SYNOPSIS
llvm-profdata command [args...]
DESCRIPTION
The llvm-profdata tool is a small utility for working with profile data
files.
COMMANDS
o merge
o show
o overlap
MERGE
SYNOPSIS
llvm-profdata merge [options] [filename...]
DESCRIPTION
llvm-profdata merge takes several profile data files generated by PGO
instrumentation and merges them together into a single indexed profile
data file.
By default profile data is merged without modification. This means that
the relative importance of each input file is proportional to the
number of samples or counts it contains. In general, the input from a
longer training run will be interpreted as relatively more important
than a shorter run. Depending on the nature of the training runs it may
be useful to adjust the weight given to each input file by using the
-weighted-input option.
Profiles passed in via -weighted-input, -input-files, or via positional
arguments are processed once for each time they are seen.
OPTIONS
--help Print a summary of command line options.
--output=<output>, -o
Specify the output file name. Output cannot be - as the
resulting indexed profile data can't be written to standard
output.
--weighted-input=<weight,filename>
Specify an input file name along with a weight. The profile
counts of the supplied filename will be scaled (multiplied) by
the supplied weight, where weight is a decimal integer >= 1.
Input files specified without using this option are assigned a
default weight of 1. Examples are shown below.
--input-files=<path>, -f
Specify a file which contains a list of files to merge. The
entries in this file are newline-separated. Lines starting with
<input-symbol> <output-symbol>. Blank lines and lines starting
with # are skipped.
The llvm-cxxmap tool can be used to generate the symbol
remapping file.
--instr (default)
Specify that the input profile is an instrumentation-based
profile.
--sample
Specify that the input profile is a sample-based profile.
The format of the generated file can be generated in one of
three ways:
--binary (default)
Emit the profile using a binary encoding. For
instrumentation-based profile the output format is the indexed
binary format.
--extbinary
Emit the profile using an extensible binary encoding. This
option can only be used with sample-based profile. The
extensible binary encoding can be more compact with compression
enabled and can be loaded faster than the default binary
encoding.
--text
Emit the profile in text mode. This option can also be used with
both sample-based and instrumentation-based profile. When this
option is used the profile will be dumped in the text format
that is parsable by the profile reader.
--gcc
Emit the profile using GCC's gcov format (Not yet supported).
--sparse[=true|false]
Do not emit function records with 0 execution count. Can only be
used in conjunction with -instr. Defaults to false, since it can
inhibit compiler optimization during PGO.
--num-threads=<N>, -j
Use N threads to perform profile merging. When N=0,
llvm-profdata auto-detects an appropriate number of threads to
use. This is the default.
--failure-mode=[any|all]
Set the failure mode. There are two options: 'any' causes the
merge command to fail if any profiles are invalid, and 'all'
causes the merge command to fail only if all profiles are
invalid. If 'all' is set, information from any invalid profiles
is excluded from the final merged product. The default failure
mode is 'any'.
Compress all sections when writing the profile. This option can
only be used with sample-based profile in extbinary format.
--use-md5=[true|false]
Use MD5 to represent string in name table when writing the
profile. This option can only be used with sample-based profile
in extbinary format.
--gen-partial-profile=[true|false]
Mark the profile to be a partial profile which only provides
partial profile coverage for the optimized target. This option
can only be used with sample-based profile in extbinary format.
--supplement-instr-with-sample=<file>
Supplement an instrumentation profile with sample profile. The
sample profile is the input of the flag. Output will be in
instrumentation format (only works with -instr).
--zero-counter-threshold=<float>
For the function which is cold in instr profile but hot in
sample profile, if the ratio of the number of zero counters
divided by the total number of counters is above the threshold,
the profile of the function will be regarded as being harmful
for performance and will be dropped.
--instr-prof-cold-threshold=<int>
User specified cold threshold for instr profile which will
override the cold threshold got from profile summary.
--suppl-min-size-threshold=<int>
If the size of a function is smaller than the threshold, assume
it can be inlined by PGO early inliner and it will not be
adjusted based on sample profile.
--debug-info=<path>
Specify the executable or .dSYM that contains debug info for the
raw profile. When -debug-info-correlate was used for
instrumentation, use this option to correlate the raw profile.
EXAMPLES
Basic Usage
Merge three profiles:
llvm-profdata merge foo.profdata bar.profdata baz.profdata -output merged.profdata
Weighted Input
The input file foo.profdata is especially important, multiply its
counts by 10:
llvm-profdata merge --weighted-input=10,foo.profdata bar.profdata baz.profdata --output merged.profdata
Exactly equivalent to the previous invocation (explicit form; useful
for programmatic invocation):
llvm-profdata merge --weighted-input=10,foo.profdata --weighted-input=1,bar.profdata --weighted-input=1,baz.profdata --output merged.profdata
SHOW
SYNOPSIS
llvm-profdata show [options] [filename]
from standard input.
OPTIONS
--all-functions
Print details for every function.
--counts
Print the counter values for the displayed functions.
--function=<string>
Print details for a function if the function's name contains the
given string.
--help Print a summary of command line options.
--output=<output>, -o
Specify the output file name. If output is - or it isn't
specified, then the output is sent to standard output.
--instr (default)
Specify that the input profile is an instrumentation-based
profile.
--text Instruct the profile dumper to show profile counts in the text
format of the instrumentation-based profile data representation.
By default, the profile information is dumped in a more human
readable form (also in text) with annotations.
--topn=<n>
Instruct the profile dumper to show the top n functions with the
hottest basic blocks in the summary section. By default, the
topn functions are not dumped.
--sample
Specify that the input profile is a sample-based profile.
--memop-sizes
Show the profiled sizes of the memory intrinsic calls for shown
functions.
--value-cutoff=<n>
Show only those functions whose max count values are greater or
equal to n. By default, the value-cutoff is set to 0.
--list-below-cutoff
Only output names of functions whose max count value are below
the cutoff value.
--showcs
Only show context sensitive profile counts. The default is to
filter all context sensitive profile counts.
--show-prof-sym-list=[true|false]
Show profile symbol list if it exists in the profile. This
option is only meaningful for sample-based profile in extbinary
format.
--show-sec-info-only=[true|false]
DESCRIPTION
llvm-profdata overlap takes two profile data files and displays the
overlap of counter distribution between the whole files and between any
of the specified functions.
In this command, overlap is defined as follows: Suppose base profile
file has the following counts: {c1_1, c1_2, ..., c1_n, c1_u_1, c2_u_2,
..., c2_u_s}, and test profile file has {c2_1, c2_2, ..., c2_n, c2_v_1,
c2_v_2, ..., c2_v_t}. Here c{1|2}_i (i = 1 .. n) are matched counters
and c1_u_i (i = 1 .. s) and c2_v_i (i = 1 .. v) are unmatched counters
(or counters only existing in) base profile file and test profile file,
respectively. Let sum_1 = c1_1 + c1_2 + ... + c1_n + c1_u_1 + c2_u_2
+ ... + c2_u_s, and sum_2 = c2_1 + c2_2 + ... + c2_n + c2_v_1 + c2_v_2
+ ... + c2_v_t. overlap = min(c1_1/sum_1, c2_1/sum_2) +
min(c1_2/sum_1, c2_2/sum_2) + ... + min(c1_n/sum_1, c2_n/sum_2).
The result overlap distribution is a percentage number, ranging from
0.0% to 100.0%, where 0.0% means there is no overlap and 100.0% means a
perfect overlap.
Here is an example, if base profile file has counts of {400, 600}, and
test profile file has matched counts of {60000, 40000}. The overlap is
80%.
OPTIONS
--function=<string>
Print details for a function if the function's name contains the
given string.
--help Print a summary of command line options.
--output=<output>, -o
Specify the output file name. If output is - or it isn't
specified, then the output is sent to standard output.
--value-cutoff=<n>
Show only those functions whose max count values are greater or
equal to n. By default, the value-cutoff is set to max of
unsigned long long.
--cs Only show overlap for the context sensitive profile counts. The
default is to show non-context sensitive profile counts.
EXIT STATUS
llvm-profdata returns 1 if the command is omitted or is invalid, if it
cannot read input files, or if there is a mismatch between their data.
AUTHOR
Maintained by the LLVM Team (https://llvm.org/).
COPYRIGHT
2003-2023, LLVM Project
15 2023-12-15 LLVM-PROFDATA(1)