2 # Copyright (C) 2014-2021 Free Software Foundation, Inc.
3 # This file is part of the GNU C Library.
5 # The GNU C Library is free software; you can redistribute it and/or
6 # modify it under the terms of the GNU Lesser General Public
7 # License as published by the Free Software Foundation; either
8 # version 2.1 of the License, or (at your option) any later version.
10 # The GNU C Library is distributed in the hope that it will be useful,
11 # but WITHOUT ANY WARRANTY; without even the implied warranty of
12 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 # Lesser General Public License for more details.
15 # You should have received a copy of the GNU Lesser General Public
16 # License along with the GNU C Library; if not, see
17 # <https://www.gnu.org/licenses/>.
19 """Benchmark program generator script
21 This script takes a function name as input and generates a program using
22 an input file located in the benchtests directory. The name of the
23 input file should be of the form foo-inputs where 'foo' is the name of
27 from __future__
import print_function
32 # Macro definitions for functions that take no arguments. For functions
33 # that take arguments, the STRUCT_TEMPLATE, ARGS_TEMPLATE and
34 # VARIANTS_TEMPLATE are used instead.
35 DEFINES_TEMPLATE
= '''
36 #define CALL_BENCH_FUNC(v, i) %(func)s ()
37 #define NUM_VARIANTS (1)
38 #define NUM_SAMPLES(v) (1)
39 #define VARIANT(v) FUNCNAME "()"
42 # Structures to store arguments for the function call. A function may
43 # have its inputs partitioned to represent distinct performance
44 # characteristics or distinct flavors of the function. Each such
45 # variant is represented by the _VARIANT structure. The ARGS structure
46 # represents a single set of arguments.
48 #define CALL_BENCH_FUNC(v, i, x) %(func)s (x %(func_args)s)
64 # The actual input arguments.
66 struct args in%(argnum)d[%(num_args)d] = {
71 # The actual variants, along with macros defined to access the variants.
72 VARIANTS_TEMPLATE
= '''
73 struct _variants variants[%(num_variants)d] = {
77 #define NUM_VARIANTS %(num_variants)d
78 #define NUM_SAMPLES(i) (variants[i].count)
79 #define VARIANT(i) (variants[i].name)
82 # Epilogue for the generated source file.
84 #define RESULT(__v, __i) (variants[(__v)].in[(__i)].timing)
85 #define RESULT_ACCUM(r, v, i, old, new) \\
86 ((RESULT ((v), (i))) = (RESULT ((v), (i)) * (old) + (r)) / ((new) + 1))
87 #define BENCH_FUNC(i, j) ({%(getret)s CALL_BENCH_FUNC (i, j, );})
88 #define BENCH_FUNC_LAT(i, j) ({%(getret)s CALL_BENCH_FUNC (i, j, %(latarg)s);})
89 #define BENCH_VARS %(defvar)s
90 #define FUNCNAME "%(func)s"
91 #include "bench-skeleton.c"'''
94 def gen_source(func
, directives
, all_vals
):
95 """Generate source for the function
97 Generate the C source for the function from the values and
101 func: The function name
102 directives: A dictionary of directives applicable to this function
103 all_vals: A dictionary input values
105 # The includes go in first.
106 for header
in directives
['includes']:
107 print('#include <%s>' % header
)
109 for header
in directives
['include-sources']:
110 print('#include "%s"' % header
)
112 # Print macros. This branches out to a separate routine if
113 # the function takes arguments.
114 if not directives
['args']:
115 print(DEFINES_TEMPLATE
% {'func': func
})
118 outargs
= _print_arg_data(func
, directives
, all_vals
)
120 # Print the output variable definitions if necessary.
124 # If we have a return value from the function, make sure it is
125 # assigned to prevent the compiler from optimizing out the
131 if directives
['ret']:
132 print('static %s volatile ret;' % directives
['ret'])
133 print('static %s zero __attribute__((used)) = 0;' % directives
['ret'])
134 getret
= 'ret = func_res = '
135 # Note this may not work if argument and result type are incompatible.
136 latarg
= 'func_res * zero +'
137 defvar
= '%s func_res = 0;' % directives
['ret']
139 # Test initialization.
140 if directives
['init']:
141 print('#define BENCH_INIT %s' % directives
['init'])
143 print(EPILOGUE
% {'getret': getret
, 'func': func
, 'latarg': latarg
, 'defvar': defvar
})
146 def _print_arg_data(func
, directives
, all_vals
):
147 """Print argument data
149 This is a helper function for gen_source that prints structure and
150 values for arguments and their variants and returns output arguments
155 directives: A dictionary of directives applicable to this function
156 all_vals: A dictionary input values
159 Returns a list of definitions for function arguments that act as
162 # First, all of the definitions. We process writing of
163 # CALL_BENCH_FUNC, struct args and also the output arguments
164 # together in a single traversal of the arguments list.
169 for arg
, i
in zip(directives
['args'], itertools
.count()):
170 if arg
[0] == '<' and arg
[-1] == '>':
173 die('Output argument must be a pointer type')
175 outargs
.append('static %s out%d __attribute__((used));' % (arg
[1:pos
], i
))
176 func_args
.append(' &out%d' % i
)
178 arg_struct
.append(' %s volatile arg%d;' % (arg
, i
))
179 func_args
.append('variants[v].in[i].arg%d' % i
)
181 print(STRUCT_TEMPLATE
% {'args' : '\n'.join(arg_struct
), 'func': func
,
182 'func_args': ', '.join(func_args
)})
184 # Now print the values.
186 for (k
, vals
), i
in zip(all_vals
.items(), itertools
.count()):
187 out
= [' {%s, 0},' % v
for v
in vals
]
189 # Members for the variants structure list that we will
191 variants
.append(' {"%s", %d, in%d},' % (k
, len(vals
), i
))
192 print(ARGS_TEMPLATE
% {'argnum': i
, 'num_args': len(vals
),
193 'args': '\n'.join(out
)})
195 # Print the variants and the last set of macros.
196 print(VARIANTS_TEMPLATE
% {'num_variants': len(all_vals
),
197 'variants': '\n'.join(variants
)})
201 def _process_directive(d_name
, d_val
):
202 """Process a directive.
204 Evaluate the directive name and value passed and return the
205 processed value. This is a helper function for parse_file.
208 d_name: Name of the directive
209 d_val: The string value to process
212 The processed value, which may be the string as it is or an object
213 that describes the directive.
215 # Process the directive values if necessary. name and ret don't
216 # need any processing.
217 if d_name
.startswith('include'):
218 d_val
= d_val
.split(',')
219 elif d_name
== 'args':
220 d_val
= d_val
.split(':')
226 def parse_file(func
):
227 """Parse an input file
229 Given a function name, open and parse an input file for the function
230 and get the necessary parameters for the generated code and the list
234 func: The function name
237 A tuple of two elements, one a dictionary of directives and the
238 other a dictionary of all input values.
246 'include-sources': [],
252 with
open('%s-inputs' % func
) as f
:
254 # Look for directives and parse it if found.
255 if line
.startswith('##'):
257 d_name
, d_val
= line
[2:].split(':', 1)
258 d_name
= d_name
.strip()
259 d_val
= d_val
.strip()
260 directives
[d_name
] = _process_directive(d_name
, d_val
)
261 except (IndexError, KeyError):
262 die('Invalid directive: %s' % line
[2:])
264 # Skip blank lines and comments.
265 line
= line
.split('#', 1)[0].rstrip()
269 # Otherwise, we're an input. Add to the appropriate
271 cur_name
= directives
['name']
272 all_vals
.setdefault(cur_name
, [])
273 all_vals
[cur_name
].append(line
)
274 except IOError as ex
:
275 die("Failed to open input file (%s): %s" % (ex
.filename
, ex
.strerror
))
277 return directives
, all_vals
281 """Exit with an error
283 Prints an error message to the standard error stream and exits with
287 msg: The error message to print to standard error
289 print('%s\n' % msg
, file=sys
.stderr
)
290 sys
.exit(os
.EX_DATAERR
)
296 Use the first command line argument as function name and parse its
297 input file to generate C source that calls the function repeatedly
301 args: The command line arguments with the program name dropped
304 os.EX_USAGE on error and os.EX_OK on success.
307 print('Usage: %s <function>' % sys
.argv
[0])
310 directives
, all_vals
= parse_file(args
[0])
311 gen_source(args
[0], directives
, all_vals
)
315 if __name__
== '__main__':
316 sys
.exit(main(sys
.argv
[1:]))