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llvm-profdata - Profile data tool

SYNOPSIS

:program:`llvm-profdata` command [args...]

DESCRIPTION

The :program:`llvm-profdata` tool is a small utility for working with profile data files.

MERGE

SYNOPSIS

:program:`llvm-profdata merge` [options] [filename...]

DESCRIPTION

:program:`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.

OPTIONS

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

:program:`llvm-profdata show` [options] [filename]

DESCRIPTION

:program:`llvm-profdata show` takes a profile data file and displays the information about the profile counters for this file and for any of the specified function(s).

If filename is omitted or is -, then llvm-profdata show reads its input from standard input.

OPTIONS

EXIT STATUS

:program:`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.