diff options
Diffstat (limited to 'Parser/asdl_c.py')
| -rwxr-xr-x | Parser/asdl_c.py | 621 |
1 files changed, 621 insertions, 0 deletions
diff --git a/Parser/asdl_c.py b/Parser/asdl_c.py new file mode 100755 index 0000000..7c6df4e --- /dev/null +++ b/Parser/asdl_c.py @@ -0,0 +1,621 @@ +#! /usr/bin/env python +"""Generate C code from an ASDL description.""" + +# TO DO +# handle fields that have a type but no name + +import os, sys, traceback + +import asdl + +TABSIZE = 8 +MAX_COL = 80 + +def get_c_type(name): + """Return a string for the C name of the type. + + This function special cases the default types provided by asdl: + identifier, string, int, bool. + """ + # XXX ack! need to figure out where Id is useful and where string + if isinstance(name, asdl.Id): + name = name.value + if name in asdl.builtin_types: + return name + else: + return "%s_ty" % name + +def reflow_lines(s, depth): + """Reflow the line s indented depth tabs. + + Return a sequence of lines where no line extends beyond MAX_COL + when properly indented. The first line is properly indented based + exclusively on depth * TABSIZE. All following lines -- these are + the reflowed lines generated by this function -- start at the same + column as the first character beyond the opening { in the first + line. + """ + size = MAX_COL - depth * TABSIZE + if len(s) < size: + return [s] + + lines = [] + cur = s + padding = "" + while len(cur) > size: + i = cur.rfind(' ', 0, size) + # XXX this should be fixed for real + if i == -1 and 'GeneratorExp' in cur: + i = size + 3 + assert i != -1, "Impossible line %d to reflow: %s" % (size, `s`) + lines.append(padding + cur[:i]) + if len(lines) == 1: + # find new size based on brace + j = cur.find('{', 0, i) + if j >= 0: + j += 2 # account for the brace and the space after it + size -= j + padding = " " * j + else: + j = cur.find('(', 0, i) + if j >= 0: + j += 1 # account for the paren (no space after it) + size -= j + padding = " " * j + cur = cur[i+1:] + else: + lines.append(padding + cur) + return lines + +def is_simple(sum): + """Return True if a sum is a simple. + + A sum is simple if its types have no fields, e.g. + unaryop = Invert | Not | UAdd | USub + """ + + for t in sum.types: + if t.fields: + return False + return True + +class EmitVisitor(asdl.VisitorBase): + """Visit that emits lines""" + + def __init__(self, file): + self.file = file + super(EmitVisitor, self).__init__() + + def emit(self, s, depth, reflow=1): + # XXX reflow long lines? + if reflow: + lines = reflow_lines(s, depth) + else: + lines = [s] + for line in lines: + line = (" " * TABSIZE * depth) + line + "\n" + self.file.write(line) + +class TypeDefVisitor(EmitVisitor): + def visitModule(self, mod): + for dfn in mod.dfns: + self.visit(dfn) + + def visitType(self, type, depth=0): + self.visit(type.value, type.name, depth) + + def visitSum(self, sum, name, depth): + if is_simple(sum): + self.simple_sum(sum, name, depth) + else: + self.sum_with_constructors(sum, name, depth) + + def simple_sum(self, sum, name, depth): + enum = [] + for i in range(len(sum.types)): + type = sum.types[i] + enum.append("%s=%d" % (type.name, i + 1)) + enums = ", ".join(enum) + ctype = get_c_type(name) + s = "typedef enum _%s { %s } %s;" % (name, enums, ctype) + self.emit(s, depth) + self.emit("", depth) + + def sum_with_constructors(self, sum, name, depth): + ctype = get_c_type(name) + s = "typedef struct _%(name)s *%(ctype)s;" % locals() + self.emit(s, depth) + self.emit("", depth) + + def visitProduct(self, product, name, depth): + ctype = get_c_type(name) + s = "typedef struct _%(name)s *%(ctype)s;" % locals() + self.emit(s, depth) + self.emit("", depth) + +class StructVisitor(EmitVisitor): + """Visitor to generate typdefs for AST.""" + + def visitModule(self, mod): + for dfn in mod.dfns: + self.visit(dfn) + + def visitType(self, type, depth=0): + self.visit(type.value, type.name, depth) + + def visitSum(self, sum, name, depth): + if not is_simple(sum): + self.sum_with_constructors(sum, name, depth) + + def sum_with_constructors(self, sum, name, depth): + def emit(s, depth=depth): + self.emit(s % sys._getframe(1).f_locals, depth) + enum = [] + for i in range(len(sum.types)): + type = sum.types[i] + enum.append("%s_kind=%d" % (type.name, i + 1)) + + emit("struct _%(name)s {") + emit("enum { " + ", ".join(enum) + " } kind;", depth + 1) + emit("union {", depth + 1) + for t in sum.types: + self.visit(t, depth + 2) + emit("} v;", depth + 1) + for field in sum.attributes: + # rudimentary attribute handling + type = str(field.type) + assert type in asdl.builtin_types, type + emit("%s %s;" % (type, field.name), depth + 1); + emit("};") + emit("") + + def visitConstructor(self, cons, depth): + if cons.fields: + self.emit("struct {", depth) + for f in cons.fields: + self.visit(f, depth + 1) + self.emit("} %s;" % cons.name, depth) + self.emit("", depth) + else: + # XXX not sure what I want here, nothing is probably fine + pass + + def visitField(self, field, depth): + # XXX need to lookup field.type, because it might be something + # like a builtin... + ctype = get_c_type(field.type) + name = field.name + if field.seq: + self.emit("asdl_seq *%(name)s;" % locals(), depth) + else: + self.emit("%(ctype)s %(name)s;" % locals(), depth) + + def visitProduct(self, product, name, depth): + self.emit("struct _%(name)s {" % locals(), depth) + for f in product.fields: + self.visit(f, depth + 1) + self.emit("};", depth) + self.emit("", depth) + +class PrototypeVisitor(EmitVisitor): + """Generate function prototypes for the .h file""" + + def visitModule(self, mod): + for dfn in mod.dfns: + self.visit(dfn) + + def visitType(self, type): + self.visit(type.value, type.name) + + def visitSum(self, sum, name): + if is_simple(sum): + pass # XXX + else: + for t in sum.types: + self.visit(t, name, sum.attributes) + + def get_args(self, fields): + """Return list of C argument into, one for each field. + + Argument info is 3-tuple of a C type, variable name, and flag + that is true if type can be NULL. + """ + args = [] + unnamed = {} + for f in fields: + if f.name is None: + name = f.type + c = unnamed[name] = unnamed.get(name, 0) + 1 + if c > 1: + name = "name%d" % (c - 1) + else: + name = f.name + # XXX should extend get_c_type() to handle this + if f.seq: + ctype = "asdl_seq *" + else: + ctype = get_c_type(f.type) + args.append((ctype, name, f.opt or f.seq)) + return args + + def visitConstructor(self, cons, type, attrs): + args = self.get_args(cons.fields) + attrs = self.get_args(attrs) + ctype = get_c_type(type) + self.emit_function(cons.name, ctype, args, attrs) + + def emit_function(self, name, ctype, args, attrs, union=1): + args = args + attrs + if args: + argstr = ", ".join(["%s %s" % (atype, aname) + for atype, aname, opt in args]) + else: + argstr = "void" + self.emit("%s %s(%s);" % (ctype, name, argstr), 0) + + def visitProduct(self, prod, name): + self.emit_function(name, get_c_type(name), + self.get_args(prod.fields), [], union=0) + +class FunctionVisitor(PrototypeVisitor): + """Visitor to generate constructor functions for AST.""" + + def emit_function(self, name, ctype, args, attrs, union=1): + def emit(s, depth=0, reflow=1): + self.emit(s, depth, reflow) + argstr = ", ".join(["%s %s" % (atype, aname) + for atype, aname, opt in args + attrs]) + self.emit("%s" % ctype, 0) + emit("%s(%s)" % (name, argstr)) + emit("{") + emit("%s p;" % ctype, 1) + for argtype, argname, opt in args: + # XXX hack alert: false is allowed for a bool + if not opt and not argtype == "bool": + emit("if (!%s) {" % argname, 1) + emit("PyErr_SetString(PyExc_ValueError,", 2) + msg = "field %s is required for %s" % (argname, name) + emit(' "%s");' % msg, + 2, reflow=0) + emit('return NULL;', 2) + emit('}', 1) + + emit("p = (%s)malloc(sizeof(*p));" % ctype, 1) + emit("if (!p) {", 1) + emit("PyErr_SetString(PyExc_MemoryError, \"no memory\");", 2) + emit("return NULL;", 2) + emit("}", 1) + if union: + self.emit_body_union(name, args, attrs) + else: + self.emit_body_struct(name, args, attrs) + emit("return p;", 1) + emit("}") + emit("") + + def emit_body_union(self, name, args, attrs): + def emit(s, depth=0, reflow=1): + self.emit(s, depth, reflow) + emit("p->kind = %s_kind;" % name, 1) + for argtype, argname, opt in args: + emit("p->v.%s.%s = %s;" % (name, argname, argname), 1) + for argtype, argname, opt in attrs: + emit("p->%s = %s;" % (argname, argname), 1) + + def emit_body_struct(self, name, args, attrs): + def emit(s, depth=0, reflow=1): + self.emit(s, depth, reflow) + for argtype, argname, opt in args: + emit("p->%s = %s;" % (argname, argname), 1) + assert not attrs + +class PickleVisitor(EmitVisitor): + + def visitModule(self, mod): + for dfn in mod.dfns: + self.visit(dfn) + + def visitType(self, type): + self.visit(type.value, type.name) + + def visitSum(self, sum, name): + pass + + def visitProduct(self, sum, name): + pass + + def visitConstructor(self, cons, name): + pass + + def visitField(self, sum): + pass + +class MarshalPrototypeVisitor(PickleVisitor): + + def prototype(self, sum, name): + ctype = get_c_type(name) + self.emit("int marshal_write_%s(PyObject **, int *, %s);" + % (name, ctype), 0) + + visitProduct = visitSum = prototype + +class FreePrototypeVisitor(PickleVisitor): + + def prototype(self, sum, name): + ctype = get_c_type(name) + self.emit("void free_%s(%s);" % (name, ctype), 0) + + visitProduct = visitSum = prototype + +_SPECIALIZED_SEQUENCES = ('stmt', 'expr') + +def find_sequence(fields, doing_specialization): + """Return True if any field uses a sequence.""" + for f in fields: + if f.seq: + if not doing_specialization: + return True + if str(f.type) not in _SPECIALIZED_SEQUENCES: + return True + return False + +def has_sequence(types, doing_specialization): + for t in types: + if find_sequence(t.fields, doing_specialization): + return True + return False + + +class StaticVisitor(PickleVisitor): + '''Very simple, always emit this static code''' + + CODE = '''static void +free_seq_exprs(asdl_seq *seq) +{ + int i, n; + n = asdl_seq_LEN(seq); + for (i = 0; i < n; i++) + free_expr((expr_ty)asdl_seq_GET(seq, i)); + asdl_seq_free(seq); +} + +static void +free_seq_stmts(asdl_seq *seq) +{ + int i, n; + n = asdl_seq_LEN(seq); + for (i = 0; i < n; i++) + free_stmt((stmt_ty)asdl_seq_GET(seq, i)); + asdl_seq_free(seq); +} +''' + + def visit(self, object): + self.emit(self.CODE, 0, reflow=False) + + +class FreeVisitor(PickleVisitor): + + def func_begin(self, name, has_seq): + ctype = get_c_type(name) + self.emit("void", 0) + self.emit("free_%s(%s o)" % (name, ctype), 0) + self.emit("{", 0) + if has_seq: + self.emit("int i, n;", 1) + self.emit("asdl_seq *seq;", 1) + self.emit('', 0) + self.emit('if (!o)', 1) + self.emit('return;', 2) + self.emit('', 0) + + def func_end(self): + self.emit("}", 0) + self.emit("", 0) + + def visitSum(self, sum, name): + has_seq = has_sequence(sum.types, True) + self.func_begin(name, has_seq) + if not is_simple(sum): + self.emit("switch (o->kind) {", 1) + for i in range(len(sum.types)): + t = sum.types[i] + self.visitConstructor(t, i + 1, name) + self.emit("}", 1) + self.emit("", 0) + self.emit("free(o);", 1) + self.func_end() + + def visitProduct(self, prod, name): + self.func_begin(name, find_sequence(prod.fields, True)) + for field in prod.fields: + self.visitField(field, name, 1, True) + self.emit("", 0) + self.emit("free(o);", 1) + self.func_end() + + def visitConstructor(self, cons, enum, name): + self.emit("case %s_kind:" % cons.name, 1) + for f in cons.fields: + self.visitField(f, cons.name, 2, False) + self.emit("break;", 2) + + def visitField(self, field, name, depth, product): + def emit(s, d): + self.emit(s, depth + d) + if product: + value = "o->%s" % field.name + else: + value = "o->v.%s.%s" % (name, field.name) + if field.seq: + self.emitSeq(field, value, depth, emit) + + # XXX need to know the simple types in advance, so that we + # don't call free_TYPE() for them. + + elif field.opt: + emit("if (%s) {" % value, 0) + self.free(field, value, depth + 1) + emit("}", 0) + else: + self.free(field, value, depth) + + def emitSeq(self, field, value, depth, emit): + # specialize for freeing sequences of statements and expressions + if str(field.type) in _SPECIALIZED_SEQUENCES: + c_code = "free_seq_%ss(%s);" % (field.type, value) + emit(c_code, 0) + else: + emit("seq = %s;" % value, 0) + emit("n = asdl_seq_LEN(seq);", 0) + emit("for (i = 0; i < n; i++)", 0) + self.free(field, "asdl_seq_GET(seq, i)", depth + 1) + emit("asdl_seq_free(seq);", 0) + + def free(self, field, value, depth): + if str(field.type) in ("identifier", "string", "object"): + ctype = get_c_type(field.type) + self.emit("Py_DECREF((%s)%s);" % (ctype, value), depth) + elif str(field.type) == "bool": + return + else: + ctype = get_c_type(field.type) + self.emit("free_%s((%s)%s);" % (field.type, ctype, value), depth) + + +class MarshalFunctionVisitor(PickleVisitor): + + def func_begin(self, name, has_seq): + ctype = get_c_type(name) + self.emit("int", 0) + self.emit("marshal_write_%s(PyObject **buf, int *off, %s o)" % + (name, ctype), 0) + self.emit("{", 0) + # XXX: add declaration of "int i;" properly + if has_seq or True: + self.emit("int i;", 1) # XXX only need it for sequences + + def func_end(self): + self.emit("return 1;", 1) + self.emit("}", 0) + self.emit("", 0) + + def visitSum(self, sum, name): + has_seq = has_sequence(sum.types, False) + self.func_begin(name, has_seq) + simple = is_simple(sum) + if simple: + self.emit("switch (o) {", 1) + else: + self.emit("switch (o->kind) {", 1) + for i in range(len(sum.types)): + t = sum.types[i] + self.visitConstructor(t, i + 1, name, simple) + self.emit("}", 1) + self.func_end() + + def visitProduct(self, prod, name): + self.func_begin(name, find_sequence(prod.fields, True)) + for field in prod.fields: + self.visitField(field, name, 1, 1) + self.func_end() + + def visitConstructor(self, cons, enum, name, simple): + if simple: + self.emit("case %s:" % cons.name, 1) + self.emit("marshal_write_int(buf, off, %d);" % enum, 2); + self.emit("break;", 2) + else: + self.emit("case %s_kind:" % cons.name, 1) + self.emit("marshal_write_int(buf, off, %d);" % enum, 2) + for f in cons.fields: + self.visitField(f, cons.name, 2, 0) + self.emit("break;", 2) + + def visitField(self, field, name, depth, product): + def emit(s, d): + self.emit(s, depth + d) + if product: + value = "o->%s" % field.name + else: + value = "o->v.%s.%s" % (name, field.name) + if field.seq: + emit("marshal_write_int(buf, off, asdl_seq_LEN(%s));" % value, 0) + emit("for (i = 0; i < asdl_seq_LEN(%s); i++) {" % value, 0) + emit("void *elt = asdl_seq_GET(%s, i);" % value, 1); + ctype = get_c_type(field.type); + emit("marshal_write_%s(buf, off, (%s)elt);" % (field.type, + ctype), 1) + emit("}", 0) + elif field.opt: + emit("if (%s) {" % value, 0) + emit("marshal_write_int(buf, off, 1);", 1) + emit("marshal_write_%s(buf, off, %s);" % (field.type, value), 1) + emit("}", 0) + emit("else {", 0) + emit("marshal_write_int(buf, off, 0);", 1) + emit("}", 0) + else: + emit("marshal_write_%s(buf, off, %s);" % (field.type, value), 0) + +class ChainOfVisitors: + def __init__(self, *visitors): + self.visitors = visitors + + def visit(self, object): + for v in self.visitors: + v.visit(object) + +def main(srcfile): + auto_gen_msg = '/* File automatically generated by %s */\n' % sys.argv[0] + mod = asdl.parse(srcfile) + if not asdl.check(mod): + sys.exit(1) + if INC_DIR: + p = "%s/%s-ast.h" % (INC_DIR, mod.name) + else: + p = "%s-ast.h" % mod.name + f = open(p, "wb") + print >> f, auto_gen_msg + print >> f, '#include "asdl.h"\n' + c = ChainOfVisitors(TypeDefVisitor(f), + StructVisitor(f), + PrototypeVisitor(f), + FreePrototypeVisitor(f), + MarshalPrototypeVisitor(f), + ) + c.visit(mod) + f.close() + + if SRC_DIR: + p = "%s/%s-ast.c" % (SRC_DIR, mod.name) + else: + p = "%s-ast.c" % mod.name + f = open(p, "wb") + print >> f, auto_gen_msg + print >> f, '#include "Python.h"' + print >> f, '#include "%s-ast.h"' % mod.name + print >> f + v = ChainOfVisitors(FunctionVisitor(f), + StaticVisitor(f), + FreeVisitor(f), + MarshalFunctionVisitor(f), + ) + v.visit(mod) + f.close() + +if __name__ == "__main__": + import sys + import getopt + + INC_DIR = '' + SRC_DIR = '' + opts, args = getopt.getopt(sys.argv[1:], "h:c:") + for o, v in opts: + if o == '-h': + INC_DIR = v + if o == '-c': + SRC_DIR = v + if len(args) != 1: + print "Must specify single input file" + main(args[0]) |