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/*
* phc -- the open source PHP compiler
* See doc/license/README.license for licensing information
*
* Reduce the amount of statement types needed by adding temporaries where
* there were none before.
*/
#include "Desugar.h"
#include "process_ir/fresh.h"
using namespace AST;
// NOP statements are removed
void Desugar::pre_nop(Nop* in, Statement_list* out)
{
// Leave "out" empty
}
// Replace "-x" by "0 - x"
Expr* Desugar::pre_unary_op(Unary_op* in)
{
if(*in->op->value == "-") return new Bin_op(
new INT(0),
in->op,
in->expr);
else
return in;
}
// TODO can we remove this?
// All return statements must get an argument (NULL if none specified)
void Desugar::pre_return(Return* in, Statement_list* out)
{
if(in->expr == NULL)
{
in->expr = new NIL();
in->expr->attrs->set_true ("phc.codegen.unused");
}
out->push_back(in);
}
void Desugar::pre_declare (Declare* in, Statement_list* out)
{
// Just remove declare statements, they dont make sense in a compiler.
}
/* Case-insensitivity
*
* The following are not case-sensitive:
* class names
* interface names
* method names
* casts
*
* However, we can only change casts since the others are needed for error
* messages.
*
* The following are case-sensitive
* constant names
* variable names
*
* We don't care about directives.
*
* We must only change their names when they are accessed, not when they are
* declared.
*/
OP*
Desugar::pre_op (OP* in)
{
in->value = in->value->to_lower();
if (*in->value == "and")
in->value = s("&&");
else if (*in->value == "or")
in->value = s("||");
else if (*in->value == "<>")
in->value = s("!=");
return in;
}
void
Desugar::pre_method (Method* in, Method_list* out)
{
out->push_back (in);
}
METHOD_NAME*
Desugar::pre_method_name (METHOD_NAME* in)
{
return in;
}
void
Desugar::pre_class_def (Class_def* in, Statement_list* out)
{
// Store for self::.
current_class = in->class_name;
// Store for parent::.
parent_class = in->extends;
out->push_back (in);
}
Expr*
Desugar::pre_constant (Constant* in)
{
return in;
}
CLASS_NAME*
Desugar::pre_class_name (CLASS_NAME* in)
{
if (*in->value == "self")
{
// self:: means the current class name.
in->value = current_class->value->clone();
}
else if (*in->value == "parent")
{
if (this->parent_class == NULL)
{
// We would ideally like to replace this with a run-time warning, but that's a bit awkward.
phc_warning ("Attempt to use 'parent::' in a class with no parent class", in);
}
else
{
// parent:: means the parent class name
in->value = parent_class->value->clone();
}
}
return in;
}
void
Desugar::pre_interface (Interface_def* in, Statement_list* out)
{
// TODO: anything special for parent here?
// Store for self::.
current_interface = in->interface_name;
out->push_back (in);
}
INTERFACE_NAME*
Desugar::pre_interface_name (INTERFACE_NAME* in)
{
if (*in->value == "self")
{
in->value = current_class->value->clone();
}
return in;
}
CAST*
Desugar::pre_cast (CAST* in)
{
in->value = in->value->to_lower ();
// Choosing the names for this is hard. We could use our IR names, but NIL
// isnt valid (isn't valid means it wont parse). We could use PHPs IS_*
// names, but long isnt valid. The manual uses NULL, but 'null' isnt valid,
// so we'll use
//
// array
// bool
// int
// object
// real
// string
// unset
//
// These are our IR names, except using unset for NIL. That should be simple
// enough to remember.
Map<string, string> cast_names;
cast_names["array"] = "array";
cast_names["binary"] = "string";
cast_names["boolean"] = "bool";
cast_names["bool"] = "bool";
cast_names["double" ] = "real";
cast_names["float"] = "real";
cast_names["integer"] = "int";
cast_names["int"] = "int";
cast_names["object"] = "object";
cast_names["real"] = "real";
cast_names["string"] = "string";
cast_names["unset"] = "unset";
assert (cast_names.has (*in->value));
in->value = s (cast_names[*in->value]);
return in;
}
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