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Diffstat (limited to 'benchtests/scripts/bench.py')
-rwxr-xr-x | benchtests/scripts/bench.py | 299 |
1 files changed, 299 insertions, 0 deletions
diff --git a/benchtests/scripts/bench.py b/benchtests/scripts/bench.py new file mode 100755 index 0000000000..e500a33ce7 --- /dev/null +++ b/benchtests/scripts/bench.py @@ -0,0 +1,299 @@ +#!/usr/bin/python +# Copyright (C) 2014 Free Software Foundation, Inc. +# This file is part of the GNU C Library. +# +# The GNU C Library is free software; you can redistribute it and/or +# modify it under the terms of the GNU Lesser General Public +# License as published by the Free Software Foundation; either +# version 2.1 of the License, or (at your option) any later version. +# +# The GNU C Library is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +# Lesser General Public License for more details. +# +# You should have received a copy of the GNU Lesser General Public +# License along with the GNU C Library; if not, see +# <http://www.gnu.org/licenses/>. + +"""Benchmark program generator script + +This script takes a function name as input and generates a program using +an input file located in the benchtests directory. The name of the +input file should be of the form foo-inputs where 'foo' is the name of +the function. +""" + +from __future__ import print_function +import sys +import os +import itertools + +# Macro definitions for functions that take no arguments. For functions +# that take arguments, the STRUCT_TEMPLATE, ARGS_TEMPLATE and +# VARIANTS_TEMPLATE are used instead. +DEFINES_TEMPLATE = ''' +#define CALL_BENCH_FUNC(v, i) %(func)s () +#define NUM_VARIANTS (1) +#define NUM_SAMPLES(v) (1) +#define VARIANT(v) FUNCNAME "()" +''' + +# Structures to store arguments for the function call. A function may +# have its inputs partitioned to represent distinct performance +# characteristics or distinct flavors of the function. Each such +# variant is represented by the _VARIANT structure. The ARGS structure +# represents a single set of arguments. +STRUCT_TEMPLATE = ''' +#define CALL_BENCH_FUNC(v, i) %(func)s (%(func_args)s) + +struct args +{ +%(args)s +}; + +struct _variants +{ + const char *name; + int count; + struct args *in; +}; +''' + +# The actual input arguments. +ARGS_TEMPLATE = ''' +struct args in%(argnum)d[%(num_args)d] = { +%(args)s +}; +''' + +# The actual variants, along with macros defined to access the variants. +VARIANTS_TEMPLATE = ''' +struct _variants variants[%(num_variants)d] = { +%(variants)s +}; + +#define NUM_VARIANTS %(num_variants)d +#define NUM_SAMPLES(i) (variants[i].count) +#define VARIANT(i) (variants[i].name) +''' + +# Epilogue for the generated source file. +EPILOGUE = ''' +#define BENCH_FUNC(i, j) ({%(getret)s CALL_BENCH_FUNC (i, j);}) +#define FUNCNAME "%(func)s" +#include "bench-skeleton.c"''' + + +def gen_source(func, directives, all_vals): + """Generate source for the function + + Generate the C source for the function from the values and + directives. + + Args: + func: The function name + directives: A dictionary of directives applicable to this function + all_vals: A dictionary input values + """ + # The includes go in first. + for header in directives['includes']: + print('#include <%s>' % header) + + for header in directives['include-sources']: + print('#include "%s"' % header) + + # Print macros. This branches out to a separate routine if + # the function takes arguments. + if not directives['args']: + print(DEFINES_TEMPLATE % {'func': func}) + outargs = [] + else: + outargs = _print_arg_data(func, directives, all_vals) + + # Print the output variable definitions if necessary. + for out in outargs: + print(out) + + # If we have a return value from the function, make sure it is + # assigned to prevent the compiler from optimizing out the + # call. + if directives['ret']: + print('static %s volatile ret;' % directives['ret']) + getret = 'ret = ' + else: + getret = '' + + print(EPILOGUE % {'getret': getret, 'func': func}) + + +def _print_arg_data(func, directives, all_vals): + """Print argument data + + This is a helper function for gen_source that prints structure and + values for arguments and their variants and returns output arguments + if any are found. + + Args: + func: Function name + directives: A dictionary of directives applicable to this function + all_vals: A dictionary input values + + Returns: + Returns a list of definitions for function arguments that act as + output parameters. + """ + # First, all of the definitions. We process writing of + # CALL_BENCH_FUNC, struct args and also the output arguments + # together in a single traversal of the arguments list. + func_args = [] + arg_struct = [] + outargs = [] + + for arg, i in zip(directives['args'], itertools.count()): + if arg[0] == '<' and arg[-1] == '>': + pos = arg.rfind('*') + if pos == -1: + die('Output argument must be a pointer type') + + outargs.append('static %s out%d;' % (arg[1:pos], i)) + func_args.append(' &out%d' % i) + else: + arg_struct.append(' %s volatile arg%d;' % (arg, i)) + func_args.append('variants[v].in[i].arg%d' % i) + + print(STRUCT_TEMPLATE % {'args' : '\n'.join(arg_struct), 'func': func, + 'func_args': ', '.join(func_args)}) + + # Now print the values. + variants = [] + for (k, vals), i in zip(all_vals.items(), itertools.count()): + out = [' {%s},' % v for v in vals] + + # Members for the variants structure list that we will + # print later. + variants.append(' {"%s(%s)", %d, in%d},' % (func, k, len(vals), i)) + print(ARGS_TEMPLATE % {'argnum': i, 'num_args': len(vals), + 'args': '\n'.join(out)}) + + # Print the variants and the last set of macros. + print(VARIANTS_TEMPLATE % {'num_variants': len(all_vals), + 'variants': '\n'.join(variants)}) + return outargs + + +def _process_directive(d_name, d_val): + """Process a directive. + + Evaluate the directive name and value passed and return the + processed value. This is a helper function for parse_file. + + Args: + d_name: Name of the directive + d_val: The string value to process + + Returns: + The processed value, which may be the string as it is or an object + that describes the directive. + """ + # Process the directive values if necessary. name and ret don't + # need any processing. + if d_name.startswith('include'): + d_val = d_val.split(',') + elif d_name == 'args': + d_val = d_val.split(':') + + # Return the values. + return d_val + + +def parse_file(func): + """Parse an input file + + Given a function name, open and parse an input file for the function + and get the necessary parameters for the generated code and the list + of inputs. + + Args: + func: The function name + + Returns: + A tuple of two elements, one a dictionary of directives and the + other a dictionary of all input values. + """ + all_vals = {} + # Valid directives. + directives = { + 'name': '', + 'args': [], + 'includes': [], + 'include-sources': [], + 'ret': '' + } + + try: + with open('%s-inputs' % func) as f: + for line in f: + # Look for directives and parse it if found. + if line.startswith('##'): + try: + d_name, d_val = line[2:].split(':', 1) + d_name = d_name.strip() + d_val = d_val.strip() + directives[d_name] = _process_directive(d_name, d_val) + except (IndexError, KeyError): + die('Invalid directive: %s' % line[2:]) + + # Skip blank lines and comments. + line = line.split('#', 1)[0].rstrip() + if not line: + continue + + # Otherwise, we're an input. Add to the appropriate + # input set. + cur_name = directives['name'] + all_vals.setdefault(cur_name, []) + all_vals[cur_name].append(line) + except IOError as ex: + die("Failed to open input file (%s): %s" % (ex.filename, ex.strerror)) + + return directives, all_vals + + +def die(msg): + """Exit with an error + + Prints an error message to the standard error stream and exits with + a non-zero status. + + Args: + msg: The error message to print to standard error + """ + print('%s\n' % msg, file=sys.stderr) + sys.exit(os.EX_DATAERR) + + +def main(args): + """Main function + + Use the first command line argument as function name and parse its + input file to generate C source that calls the function repeatedly + for the input. + + Args: + args: The command line arguments with the program name dropped + + Returns: + os.EX_USAGE on error and os.EX_OK on success. + """ + if len(args) != 1: + print('Usage: %s <function>' % sys.argv[0]) + return os.EX_USAGE + + directives, all_vals = parse_file(args[0]) + gen_source(args[0], directives, all_vals) + return os.EX_OK + + +if __name__ == '__main__': + sys.exit(main(sys.argv[1:])) |