Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help 
LLVM-REDUCE(1)			     LLVM			LLVM-REDUCE(1)

NAME
       llvm-reduce - LLVM automatic testcase reducer.

SYNOPSIS
       llvm-reduce [options] [input...]

DESCRIPTION
       The  llvm-reduce	tool project that can be used for reducing the size of
       LLVM test cases.	 It works by removing redundant	 or  unnecessary  code
       from  LLVM  test	 cases	while still preserving their ability to	detect
       bugs.

       If input	is "-",	llvm-reduce reads from standard	input.	Otherwise,  it
       will read from the specified filenames.

       LLVM-Reduce  is	a  useful tool for reducing the	size and complexity of
       LLVM test cases,	making it easier to identify and debug issues  in  the
       LLVM compiler infrastructure.

GENERIC	OPTIONS
       --help Display available	options	(--help-hidden for more).

       --abort-on-invalid-reduction
	      Abort if any reduction results in	invalid	IR

       --in-place
	      WARNING:	This  option will replace your input file with the re-
	      duced version!

       --ir-passes=<string>
	      A	textual	description of	the  pass  pipeline,  same  as	what's
	      passed to	opt -passes.

       -j <uint>
	      Maximum  number of threads to use	to process chunks. Set to 1 to
	      disable parallelism.

       --max-pass-iterations=<int>
	      Maximum number of	times to run the full set of delta passes (de-
	      fault=5).

       --mtriple=<string>
	      Set the target triple.

       --preserve-debug-environment
	      Don't disable features used for crash debugging (crash  reports,
	      llvm-symbolizer and core dumps)

       --print-delta-passes
	      Print  list  of  delta  passes,  passable	to --delta-passes as a
	      comma separated liste.

       --skip-delta-passes=<string>
	      Delta passes to not run, separated by commas.  By	 default,  run
	      all delta	passes.

       --starting-granularity-level=<uint>
	      Number of	times to divide	chunks prior to	first test.

	      Note  :  Granularity  refers to the level	of detail at which the
	      reduction	process	operates.  A lower granularity means that  the
	      reduction	process	operates at a more coarse-grained level, while
	      a	  higher   granularity	means  that  it	 operates  at  a  more
	      fine-grained level.

       --test=<string>
	      Name of the interesting-ness test	to be run.

       --test-arg=<string>
	      Arguments	passed onto the	interesting-ness test.

       --verbose
	      Print extra debugging information.

       --write-tmp-files-as-bitcode
	      Always write temporary files as bitcode instead of textual IR.

       -x={ir|mir}
	      Input language as	ir or mir.

EXIT STATUS
       llvm-reduce returns 0 under normal operation.  It  returns  a  non-zero
       exit code if there were any errors.

EXAMPLE
       llvm-reduce  can	 be  used  to  simplify	 a test	that causes a compiler
       crash.

       For example, let's assume that opt is crashing on the IR	 file  test.ll
       with  error  message Assertion failed at	line 1234 of WhateverFile.cpp,
       when running at -O2.

       The test	case of	test.ll	can be reduced by invoking the following  com-
       mand:

	  $(LLVM_BUILD_FOLDER)/bin/llvm-reduce --test=script.sh	<path to>/test.ll

       The shell script	passed to the option test consists of the following:

	  $(LLVM_BUILD_FOLDER)/bin/opt -O2 -disable-output $1 \
	    |& grep "Assertion failed at line 1234 of WhateverFile.cpp"

       (In  this script, grep exits with 0 if it finds the string and that be-
       comes the whole script's	status.)

       This example can	be generalized to other	tools that process  IR	files,
       for example llc.

AUTHOR
       Maintained by the LLVM Team (https://llvm.org/).

COPYRIGHT
       2003-2025, LLVM Project

18				  2025-04-13			LLVM-REDUCE(1)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=llvm-reduce-cheriot&sektion=1&manpath=FreeBSD+Ports+14.3.quarterly>

home | help