compilef.py 文件源码

def genfcode(lambdastr, use_cse=False):
    """
    Python lambda string -> C function code

    Optionally cse() is used to eliminate common subexpressions.
    """
    # TODO: verify lambda string
    # interpret lambda string
    varstr, fstr = lambdastr.split(': ')
    varstr = varstr.lstrip('lambda ')
    # generate C variable string
    cvars = varstr.split(',')
    cvarstr = ''
    for v in cvars:
        cvarstr += 'double %s, ' % v
    cvarstr = cvarstr.rstrip(', ')
    # convert function string to C syntax
    if not use_cse:
        cfstr = ''
        finalexpr = cexpr(fstr)
    else:
        # eliminate common subexpressions
        subs, finalexpr = cse(sympify(fstr), _gentmpvars())
        if len(finalexpr) != 1:
            raise ValueError("Length should be 1")
        vardec = ''
        cfstr = ''
        for symbol, expr in subs:
            vardec += '    double %s;\n' % symbol.name
            cfstr += '    %s = %s;\n' % (
                symbol.name, cexpr(str(expr.evalf(dps))))
        cfstr = vardec + cfstr
        finalexpr = cexpr(str(finalexpr[0].evalf(dps)))
    # generate C code
    code = """
inline double f(%s)
    {
%s
    return %s;
    }
""" % (cvarstr, cfstr, finalexpr)
    return code