Provided by: llvm-6.0_6.0.1-9_amd64 bug

NAME

       llvm-bcanalyzer - LLVM bitcode analyzer

SYNOPSIS

       llvm-bcanalyzer [options] [filename]

DESCRIPTION

       The  llvm-bcanalyzer  command  is  a  small utility for analyzing bitcode files.  The tool
       reads a bitcode file (such as generated with the llvm-as tool) and produces a  statistical
       report  on the contents of the bitcode file.  The tool can also dump a low level but human
       readable version of the bitcode file.  This tool is  probably  not  of  much  interest  or
       utility  except  for those working directly with the bitcode file format.  Most LLVM users
       can just ignore this tool.

       If filename is omitted or is -, then llvm-bcanalyzer reads its input from standard  input.
       This  is useful for combining the tool into a pipeline.  Output is written to the standard
       output.

OPTIONS

       -nodetails
              Causes llvm-bcanalyzer to abbreviate its output by writing out only a module  level
              summary.  The details for individual functions are not displayed.

       -dump  Causes llvm-bcanalyzer to dump the bitcode in a human readable format.  This format
              is significantly different from  LLVM  assembly  and  provides  details  about  the
              encoding of the bitcode file.

       -verify
              Causes  llvm-bcanalyzer to verify the module produced by reading the bitcode.  This
              ensures that the statistics generated are based on a consistent module.

       -help  Print a summary of command line options.

EXIT STATUS

       If llvm-bcanalyzer succeeds, it will exit with 0.  Otherwise, if an error occurs, it  will
       exit with a non-zero value, usually 1.

SUMMARY OUTPUT DEFINITIONS

       The  following  items  are  always  printed by llvm-bcanalyzer.  They comprize the summary
       output.

       Bitcode Analysis Of Module
          This just provides the  name  of  the  module  for  which  bitcode  analysis  is  being
          generated.

       Bitcode Version Number
          The bitcode version (not LLVM version) of the file read by the analyzer.

       File Size
          The size, in bytes, of the entire bitcode file.

       Module Bytes
          The size, in bytes, of the module block.  Percentage is relative to File Size.

       Function Bytes
          The size, in bytes, of all the function blocks.  Percentage is relative to File Size.

       Global Types Bytes
          The  size,  in  bytes,  of the Global Types Pool.  Percentage is relative to File Size.
          This is the size of the definitions of all types in the bitcode file.

       Constant Pool Bytes
          The size, in bytes, of the Constant Pool Blocks Percentage is relative to File Size.

       Module Globals Bytes
          Ths size, in  bytes,  of  the  Global  Variable  Definitions  and  their  initializers.
          Percentage is relative to File Size.

       Instruction List Bytes
          The  size,  in bytes, of all the instruction lists in all the functions.  Percentage is
          relative to File Size.  Note that this value is also included in the Function Bytes.

       Compaction Table Bytes
          The size, in bytes, of all the compaction tables in all the functions.   Percentage  is
          relative to File Size.  Note that this value is also included in the Function Bytes.

       Symbol Table Bytes
          The  size,  in  bytes,  of  all  the symbol tables in all the functions.  Percentage is
          relative to File Size.  Note that this value is also included in the Function Bytes.

       Dependent Libraries Bytes
          The size, in bytes, of the list of dependent libraries in the  module.   Percentage  is
          relative  to  File  Size.   Note  that this value is also included in the Module Global
          Bytes.

       Number Of Bitcode Blocks
          The total number of blocks of any kind in the bitcode file.

       Number Of Functions
          The total number of function definitions in the bitcode file.

       Number Of Types
          The total number of types defined in the Global Types Pool.

       Number Of Constants
          The total number of constants (of any type) defined in the Constant Pool.

       Number Of Basic Blocks
          The total number of basic blocks defined in all functions in the bitcode file.

       Number Of Instructions
          The total number of instructions defined in all functions in the bitcode file.

       Number Of Long Instructions
          The total number of long instructions defined in all functions  in  the  bitcode  file.
          Long  instructions  are those taking greater than 4 bytes.  Typically long instructions
          are GetElementPtr with several indices, PHI nodes, and calls to  functions  with  large
          numbers of arguments.

       Number Of Operands
          The total number of operands used in all instructions in the bitcode file.

       Number Of Compaction Tables
          The total number of compaction tables in all functions in the bitcode file.

       Number Of Symbol Tables
          The total number of symbol tables in all functions in the bitcode file.

       Number Of Dependent Libs
          The total number of dependent libraries found in the bitcode file.

       Total Instruction Size
          The total size of the instructions in all functions in the bitcode file.

       Average Instruction Size
          The  average  number of bytes per instruction across all functions in the bitcode file.
          This value is computed by dividing Total Instruction Size by Number Of Instructions.

       Maximum Type Slot Number
          The maximum value used for a type’s slot number.  Larger slot number values  take  more
          bytes to encode.

       Maximum Value Slot Number
          The  maximum value used for a value’s slot number.  Larger slot number values take more
          bytes to encode.

       Bytes Per Value
          The average size of a Value definition (of any type).  This  is  computed  by  dividing
          File Size by the total number of values of any type.

       Bytes Per Global
          The average size of a global definition (constants and global variables).

       Bytes Per Function
          The  average  number  of  bytes  per function definition.  This is computed by dividing
          Function Bytes by Number Of Functions.

       # of VBR 32-bit Integers
          The total number of 32-bit integers  encoded  using  the  Variable  Bit  Rate  encoding
          scheme.

       # of VBR 64-bit Integers
          The  total  number  of  64-bit  integers  encoded  using the Variable Bit Rate encoding
          scheme.

       # of VBR Compressed Bytes
          The total number of bytes consumed by the 32-bit  and  64-bit  integers  that  use  the
          Variable Bit Rate encoding scheme.

       # of VBR Expanded Bytes
          The  total  number  of  bytes  that  would  have been consumed by the 32-bit and 64-bit
          integers had they not been compressed with the Variable Bit Rage encoding scheme.

       Bytes Saved With VBR
          The total number of bytes saved by using the Variable Bit Rate  encoding  scheme.   The
          percentage is relative to # of VBR Expanded Bytes.

DETAILED OUTPUT DEFINITIONS

       The following definitions occur only if the -nodetails option was not given.  The detailed
       output provides additional information on a per-function basis.

       Type
          The type signature of the function.

       Byte Size
          The total number of bytes in the function’s block.

       Basic Blocks
          The number of basic blocks defined by the function.

       Instructions
          The number of instructions defined by the function.

       Long Instructions
          The number of instructions using the long instruction format in the function.

       Operands
          The number of operands used by all instructions in the function.

       Instruction Size
          The number of bytes consumed by instructions in the function.

       Average Instruction Size
          The average number of bytes consumed by the instructions in the function.   This  value
          is computed by dividing Instruction Size by Instructions.

       Bytes Per Instruction
          The  average  number  of  bytes  used  by  the function per instruction.  This value is
          computed by dividing Byte Size by Instructions.  Note that this  is  not  the  same  as
          Average Instruction Size.  It computes a number relative to the total function size not
          just the size of the instruction list.

       Number of VBR 32-bit Integers
          The total number of 32-bit integers found in this function (for any use).

       Number of VBR 64-bit Integers
          The total number of 64-bit integers found in this function (for any use).

       Number of VBR Compressed Bytes
          The total number of bytes in this function consumed by the 32-bit and  64-bit  integers
          that use the Variable Bit Rate encoding scheme.

       Number of VBR Expanded Bytes
          The  total number of bytes in this function that would have been consumed by the 32-bit
          and 64-bit integers had they not been compressed with the Variable  Bit  Rate  encoding
          scheme.

       Bytes Saved With VBR
          The  total  number  of  bytes  saved  in  this  function by using the Variable Bit Rate
          encoding scheme.  The percentage is relative to # of VBR Expanded Bytes.

SEE ALSO

       /CommandGuide/llvm-dis, /BitCodeFormat

AUTHOR

       Maintained by The LLVM Team (http://llvm.org/).

COPYRIGHT

       2003-2018, LLVM Project