#include "Qualify.h"
#include "IRMutator.h"

namespace Halide {
namespace Internal {

using std::string;

namespace {

// Prefix all names in an expression with some string.
class QualifyExpr : public IRMutator {
 using IRMutator::visit;

 const string &prefix;

 Expr visit(const Variable *v) override {
 if (v->param.defined()) {
 return v;
 } else {
 return Variable::make(v->type, prefix + v->name, v->reduction_domain);
 }
 }
 Expr visit(const Let *op) override {
 Expr value = mutate(op->value);
 Expr body = mutate(op->body);
 return Let::make(prefix + op->name, value, body);
 }

public:
 QualifyExpr(const string &p)
 : prefix(p) {
 }
};

} // namespace

Expr qualify(const string &prefix, const Expr &value) {
 QualifyExpr q(prefix);
 return q.mutate(value);
}

} // namespace Internal
} // namespace Halide