1LLVM-BCANALYZER(1) LLVM Command Guide LLVM-BCANALYZER(1)
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6 llvm-bcanalyzer - LLVM bitcode analyzer
7
9 llvm-bcanalyzer [options] [filename]
10
12 The llvm-bcanalyzer command is a small utility for analyzing bitcode
13 files. The tool reads a bitcode file (such as generated with the llvm-
14 as tool) and produces a statistical report on the contents of the
15 bitcode file. The tool can also dump a low level but human readable
16 version of the bitcode file. This tool is probably not of much
17 interest or utility except for those working directly with the bitcode
18 file format. Most LLVM users can just ignore this tool.
19 If filename is omitted or is "-", then llvm-bcanalyzer reads its input
21 from standard input. This is useful for combining the tool into a
22 pipeline. Output is written to the standard output.
23
25 -nodetails
26 Causes llvm-bcanalyzer to abbreviate its output by writing out only
27 a module level summary. The details for individual functions are
28 not displayed.
29 -dump
31 Causes llvm-bcanalyzer to dump the bitcode in a human readable
32 format. This format is significantly different from LLVM assembly
33 and provides details about the encoding of the bitcode file.
34 -verify
36 Causes llvm-bcanalyzer to verify the module produced by reading the
37 bitcode. This ensures that the statistics generated are based on a
38 consistent module.
39 -help
41 Print a summary of command line options.
42
44 If llvm-bcanalyzer succeeds, it will exit with 0. Otherwise, if an
45 error occurs, it will exit with a non-zero value, usually 1.
46
48 The following items are always printed by llvm-bcanalyzer. They
49 comprize the summary output.
50 Bitcode Analysis Of Module
52 This just provides the name of the module for which bitcode
53 analysis is being generated.
54 Bitcode Version Number
56 The bitcode version (not LLVM version) of the file read by the
57 analyzer.
58 File Size
60 The size, in bytes, of the entire bitcode file.
61 Module Bytes
63 The size, in bytes, of the module block. Percentage is relative to
64 File Size.
65 Function Bytes
67 The size, in bytes, of all the function blocks. Percentage is
68 relative to File Size.
69 Global Types Bytes
71 The size, in bytes, of the Global Types Pool. Percentage is
72 relative to File Size. This is the size of the definitions of all
73 types in the bitcode file.
74 Constant Pool Bytes
76 The size, in bytes, of the Constant Pool Blocks Percentage is
77 relative to File Size.
78 Module Globals Bytes
80 Ths size, in bytes, of the Global Variable Definitions and their
81 initializers. Percentage is relative to File Size.
82 Instruction List Bytes
84 The size, in bytes, of all the instruction lists in all the
85 functions. Percentage is relative to File Size. Note that this
86 value is also included in the Function Bytes.
87 Compaction Table Bytes
89 The size, in bytes, of all the compaction tables in all the
90 functions. Percentage is relative to File Size. Note that this
91 value is also included in the Function Bytes.
92 Symbol Table Bytes
94 The size, in bytes, of all the symbol tables in all the functions.
95 Percentage is relative to File Size. Note that this value is also
96 included in the Function Bytes.
97 Dependent Libraries Bytes
99 The size, in bytes, of the list of dependent libraries in the
100 module. Percentage is relative to File Size. Note that this value
101 is also included in the Module Global Bytes.
102 Number Of Bitcode Blocks
104 The total number of blocks of any kind in the bitcode file.
105 Number Of Functions
107 The total number of function definitions in the bitcode file.
108 Number Of Types
110 The total number of types defined in the Global Types Pool.
111 Number Of Constants
113 The total number of constants (of any type) defined in the Constant
114 Pool.
115 Number Of Basic Blocks
117 The total number of basic blocks defined in all functions in the
118 bitcode file.
119 Number Of Instructions
121 The total number of instructions defined in all functions in the
122 bitcode file.
123 Number Of Long Instructions
125 The total number of long instructions defined in all functions in
126 the bitcode file. Long instructions are those taking greater than 4
127 bytes. Typically long instructions are GetElementPtr with several
128 indices, PHI nodes, and calls to functions with large numbers of
129 arguments.
130 Number Of Operands
132 The total number of operands used in all instructions in the
133 bitcode file.
134 Number Of Compaction Tables
136 The total number of compaction tables in all functions in the
137 bitcode file.
138 Number Of Symbol Tables
140 The total number of symbol tables in all functions in the bitcode
141 file.
142 Number Of Dependent Libs
144 The total number of dependent libraries found in the bitcode file.
145 Total Instruction Size
147 The total size of the instructions in all functions in the bitcode
148 file.
149 Average Instruction Size
151 The average number of bytes per instruction across all functions in
152 the bitcode file. This value is computed by dividing Total
153 Instruction Size by Number Of Instructions.
154 Maximum Type Slot Number
156 The maximum value used for a type's slot number. Larger slot number
157 values take more bytes to encode.
158 Maximum Value Slot Number
160 The maximum value used for a value's slot number. Larger slot
161 number values take more bytes to encode.
162 Bytes Per Value
164 The average size of a Value definition (of any type). This is
165 computed by dividing File Size by the total number of values of any
166 type.
167 Bytes Per Global
169 The average size of a global definition (constants and global
170 variables).
171 Bytes Per Function
173 The average number of bytes per function definition. This is
174 computed by dividing Function Bytes by Number Of Functions.
175 # of VBR 32-bit Integers
177 The total number of 32-bit integers encoded using the Variable Bit
178 Rate encoding scheme.
179 # of VBR 64-bit Integers
181 The total number of 64-bit integers encoded using the Variable Bit
182 Rate encoding scheme.
183 # of VBR Compressed Bytes
185 The total number of bytes consumed by the 32-bit and 64-bit
186 integers that use the Variable Bit Rate encoding scheme.
187 # of VBR Expanded Bytes
189 The total number of bytes that would have been consumed by the
190 32-bit and 64-bit integers had they not been compressed with the
191 Variable Bit Rage encoding scheme.
192 Bytes Saved With VBR
194 The total number of bytes saved by using the Variable Bit Rate
195 encoding scheme. The percentage is relative to # of VBR Expanded
196 Bytes.
197
199 The following definitions occur only if the -nodetails option was not
200 given. The detailed output provides additional information on a per-
201 function basis.
202 Type
204 The type signature of the function.
205 Byte Size
207 The total number of bytes in the function's block.
208 Basic Blocks
210 The number of basic blocks defined by the function.
211 Instructions
213 The number of instructions defined by the function.
214 Long Instructions
216 The number of instructions using the long instruction format in the
217 function.
218 Operands
220 The number of operands used by all instructions in the function.
221 Instruction Size
223 The number of bytes consumed by instructions in the function.
224 Average Instruction Size
226 The average number of bytes consumed by the instructions in the
227 funtion. This value is computed by dividing Instruction Size by
228 Instructions.
229 Bytes Per Instruction
231 The average number of bytes used by the function per instruction.
232 This value is computed by dividing Byte Size by Instructions. Note
233 that this is not the same as Average Instruction Size. It computes
234 a number relative to the total function size not just the size of
235 the instruction list.
236 Number of VBR 32-bit Integers
238 The total number of 32-bit integers found in this function (for any
239 use).
240 Number of VBR 64-bit Integers
242 The total number of 64-bit integers found in this function (for any
243 use).
244 Number of VBR Compressed Bytes
246 The total number of bytes in this function consumed by the 32-bit
247 and 64-bit integers that use the Variable Bit Rate encoding scheme.
248 Number of VBR Expanded Bytes
250 The total number of bytes in this function that would have been
251 consumed by the 32-bit and 64-bit integers had they not been
252 compressed with the Variable Bit Rate encoding scheme.
253 Bytes Saved With VBR
255 The total number of bytes saved in this function by using the
256 Variable Bit Rate encoding scheme. The percentage is relative to #
257 of VBR Expanded Bytes.
258
260 llvm-dis, <http://llvm.org/docs/BitCodeFormat.html>
261
263 Maintained by the LLVM Team (<http://llvm.org>).
264CVS 2010-05-07 LLVM-BCANALYZER(1)