Mercurial > cpython-lru_cache-weakref
diff Python/makeopcodetargets.py @ 51031:d86e23318b41
Issue #4753: By enabling a configure option named '--with-computed-gotos'
on compilers that support it (notably: gcc, SunPro, icc), the bytecode
evaluation loop is compiled with a new dispatch mechanism which gives
speedups of up to 20%, depending on the system, on various benchmarks.
| author | Antoine Pitrou <solipsis@pitrou.net> |
|---|---|
| date | Sun, 25 Jan 2009 16:34:23 +0000 |
| parents | |
| children | df090597afaa |
line wrap: on
line diff
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/Python/makeopcodetargets.py Sun Jan 25 16:34:23 2009 +0000 @@ -0,0 +1,43 @@ +#! /usr/bin/env python +"""Generate C code for the jump table of the threaded code interpreter +(for compilers supporting computed gotos or "labels-as-values", such as gcc). +""" + +import imp +import os + + +def find_module(modname): + """Finds and returns a module in the local dist/checkout. + """ + modpath = os.path.join( + os.path.dirname(os.path.dirname(__file__)), "Lib") + return imp.load_module(modname, *imp.find_module(modname, [modpath])) + +def write_contents(f): + """Write C code contents to the target file object. + """ + opcode = find_module("opcode") + targets = ['_unknown_opcode'] * 256 + for opname, op in opcode.opmap.items(): + if opname == "STOP_CODE": + # XXX opcode not implemented + continue + targets[op] = "TARGET_%s" % opname + f.write("static void *opcode_targets[256] = {\n") + f.write(",\n".join("\t&&%s" % s for s in targets)) + f.write("\n};\n") + + +if __name__ == "__main__": + import sys + assert len(sys.argv) < 3, "Too many arguments" + if len(sys.argv) == 2: + target = sys.argv[1] + else: + target = "Python/opcode_targets.h" + f = open(target, "w") + try: + write_contents(f) + finally: + f.close()
