← Back
Editing: argument_read_once.py
""" ArgumentReadOnce counts the usages of each argument of each function. """ from pythran.analyses.aliases import Aliases from pythran.analyses.global_declarations import GlobalDeclarations from pythran.passmanager import ModuleAnalysis from pythran.tables import MODULES import pythran.intrinsic as intrinsic import gast as ast from functools import reduce class ArgumentReadOnce(ModuleAnalysis): """ Counts the usages of each argument of each function. Attributes ---------- result : {FunctionEffects} Number of use for each argument of each function. node_to_functioneffect : {???: ???} FunctionDef ast node to function effect binding. """ class FunctionEffects(object): def __init__(self, node): self.func = node self.dependencies = lambda ctx: 0 if isinstance(node, ast.FunctionDef): self.read_effects = [-1] * len(node.args.args) elif isinstance(node, intrinsic.Intrinsic): self.read_effects = [ 1 if isinstance(x, intrinsic.ReadOnceEffect) else 2 for x in node.argument_effects] elif isinstance(node, ast.alias): self.read_effects = [] else: raise NotImplementedError class ConstructorEffects(object): def __init__(self, node): self.func = node self.dependencies = lambda ctx: 0 self.read_effects = [0] class Context(object): def __init__(self, function, index, path, global_dependencies): self.function = function self.index = index self.path = path self.global_dependencies = global_dependencies def __init__(self): """ Basic initialiser for class attributes. """ self.result = set() self.node_to_functioneffect = dict() super(ArgumentReadOnce, self).__init__(Aliases, GlobalDeclarations) def prepare(self, node): """ Initialise arguments effects as this analysis in inter-procedural. Initialisation done for Pythonic functions and default values set for user defined functions. """ super(ArgumentReadOnce, self).prepare(node) # global functions init for n in self.global_declarations.values(): fe = ArgumentReadOnce.FunctionEffects(n) self.node_to_functioneffect[n] = fe self.result.add(fe) # Pythonic functions init def save_effect(module): """ Recursively save read once effect for Pythonic functions. """ for intr in module.values(): if isinstance(intr, dict): # Submodule case save_effect(intr) else: fe = ArgumentReadOnce.FunctionEffects(intr) self.node_to_functioneffect[intr] = fe self.result.add(fe) if isinstance(intr, intrinsic.Class): # Class case save_effect(intr.fields) for module in MODULES.values(): save_effect(module) def run(self, node): result = super(ArgumentReadOnce, self).run(node) for fun in result: for i in range(len(fun.read_effects)): self.recursive_weight(fun, i, set()) self.result = {f.func: f.read_effects for f in result} return self.result def recursive_weight(self, function, index, predecessors): # TODO : Find out why it happens in some cases if len(function.read_effects) <= index: return 0 if function.read_effects[index] == -1: # In case of recursive/cyclic calls cycle = function in predecessors predecessors.add(function) if cycle: function.read_effects[index] = 2 * function.dependencies( ArgumentReadOnce.Context(function, index, predecessors, False)) else: function.read_effects[index] = function.dependencies( ArgumentReadOnce.Context(function, index, predecessors, True)) return function.read_effects[index] def argument_index(self, node): while isinstance(node, ast.Subscript): node = node.value if node in self.aliases: for n_alias in self.aliases[node]: try: return self.current_function.func.args.args.index(n_alias) except ValueError: pass return -1 def local_effect(self, node, effect): index = self.argument_index(node) return lambda ctx: effect if index == ctx.index else 0 def generic_visit(self, node): lambdas = [self.visit(child) for child in ast.iter_child_nodes(node)] return lambda ctx: sum(l(ctx) for l in lambdas) def visit_FunctionDef(self, node): self.current_function = self.node_to_functioneffect[node] assert self.current_function in self.result self.current_function.dependencies = self.generic_visit(node) def visit_Return(self, node): dep = self.generic_visit(node) if isinstance(node.value, ast.Name): local = self.local_effect(node.value, 2) return lambda ctx: dep(ctx) + local(ctx) else: return dep def visit_Assign(self, node): dep = self.generic_visit(node) local = [self.local_effect(t, 2) for t in node.targets if isinstance(t, ast.Subscript)] return lambda ctx: dep(ctx) + sum(l(ctx) for l in local) def visit_AugAssign(self, node): dep = self.generic_visit(node) local = self.local_effect(node.target, 2) return lambda ctx: dep(ctx) + local(ctx) def visit_For(self, node): iter_local = self.local_effect(node.iter, 1) iter_deps = self.visit(node.iter) body_deps = [self.visit(stmt) for stmt in node.body] else_deps = [self.visit(stmt) for stmt in node.orelse] return lambda ctx: iter_local(ctx) + iter_deps(ctx) + 2 * sum( l(ctx) for l in body_deps) + sum(l(ctx) for l in else_deps) def visit_While(self, node): test_deps = self.visit(node.test) body_deps = [self.visit(stmt) for stmt in node.body] else_deps = [self.visit(stmt) for stmt in node.orelse] return lambda ctx: test_deps(ctx) + 2 * sum( l(ctx) for l in body_deps) + sum(l(ctx) for l in else_deps) def visit_If(self, node): test_deps = self.visit(node.test) body_deps = [self.visit(stmt) for stmt in node.body] else_deps = [self.visit(stmt) for stmt in node.orelse] return lambda ctx: test_deps(ctx) + max(sum( l(ctx) for l in body_deps), sum(l(ctx) for l in else_deps)) def visit_Call(self, node): l0 = self.generic_visit(node) index_corres = dict() func = None for i, arg in enumerate(node.args): n = self.argument_index(arg) if n >= 0: func_aliases = self.aliases[node.func] # expand argument if any func_aliases = reduce( lambda x, y: x + ( # all functions list(self.node_to_functioneffect.keys()) if (isinstance(y, ast.Name) and self.argument_index(y) >= 0) else [y]), func_aliases, list()) for func_alias in func_aliases: # special hook for binded functions if isinstance(func_alias, ast.Call): bound_name = func_alias.args[0].id func_alias = self.global_declarations[bound_name] if func_alias is intrinsic.UnboundValue: continue if func_alias not in self.node_to_functioneffect: continue func = self.node_to_functioneffect[func_alias] index_corres[n] = i def merger(ctx): base = l0(ctx) if (ctx.index in index_corres) and ctx.global_dependencies: rec = self.recursive_weight(func, index_corres[ctx.index], ctx.path) else: rec = 0 return base + rec return merger def visit_Subscript(self, node): dep = self.generic_visit(node) local = self.local_effect(node.value, 2) return lambda ctx: dep(ctx) + local(ctx) def visit_comprehension(self, node): dep = self.generic_visit(node) local = self.local_effect(node.iter, 1) return lambda ctx: dep(ctx) + local(ctx)
Save File
Cancel