IRVisitor.h
#ifndef HALIDE_IR_VISITOR_H
#define HALIDE_IR_VISITOR_H
#include <set>
#include "IR.h"
/** \file
* Defines the base class for things that recursively walk over the IR
*/
namespace Halide {
namespace Internal {
/** A base class for algorithms that need to recursively walk over the
* IR. The default implementations just recursively walk over the
* children. Override the ones you care about.
*/
class IRVisitor {
public:
IRVisitor() = default;
virtual ~IRVisitor() = default;
protected:
// ExprNode<> and StmtNode<> are allowed to call visit (to implement accept())
template<typename T>
friend struct ExprNode;
template<typename T>
friend struct StmtNode;
virtual void visit(const IntImm *);
virtual void visit(const UIntImm *);
virtual void visit(const FloatImm *);
virtual void visit(const StringImm *);
virtual void visit(const Cast *);
virtual void visit(const Variable *);
virtual void visit(const Add *);
virtual void visit(const Sub *);
virtual void visit(const Mul *);
virtual void visit(const Div *);
virtual void visit(const Mod *);
virtual void visit(const Min *);
virtual void visit(const Max *);
virtual void visit(const EQ *);
virtual void visit(const NE *);
virtual void visit(const LT *);
virtual void visit(const LE *);
virtual void visit(const GT *);
virtual void visit(const GE *);
virtual void visit(const And *);
virtual void visit(const Or *);
virtual void visit(const Not *);
virtual void visit(const Select *);
virtual void visit(const Load *);
virtual void visit(const Ramp *);
virtual void visit(const Broadcast *);
virtual void visit(const Call *);
virtual void visit(const Let *);
virtual void visit(const LetStmt *);
virtual void visit(const AssertStmt *);
virtual void visit(const ProducerConsumer *);
virtual void visit(const For *);
virtual void visit(const Store *);
virtual void visit(const Provide *);
virtual void visit(const Allocate *);
virtual void visit(const Free *);
virtual void visit(const Realize *);
virtual void visit(const Block *);
virtual void visit(const IfThenElse *);
virtual void visit(const Evaluate *);
virtual void visit(const Shuffle *);
virtual void visit(const VectorReduce *);
virtual void visit(const Prefetch *);
virtual void visit(const Fork *);
virtual void visit(const Acquire *);
virtual void visit(const Atomic *);
};
/** A base class for algorithms that walk recursively over the IR
* without visiting the same node twice. This is for passes that are
* capable of interpreting the IR as a DAG instead of a tree. */
class IRGraphVisitor : public IRVisitor {
protected:
/** By default these methods add the node to the visited set, and
* return whether or not it was already there. If it wasn't there,
* it delegates to the appropriate visit method. You can override
* them if you like. */
// @{
virtual void include(const Expr &);
virtual void include(const Stmt &);
// @}
private:
/** The nodes visited so far */
std::set<IRHandle> visited;
protected:
/** These methods should call 'include' on the children to only
* visit them if they haven't been visited already. */
// @{
void visit(const IntImm *) override;
void visit(const UIntImm *) override;
void visit(const FloatImm *) override;
void visit(const StringImm *) override;
void visit(const Cast *) override;
void visit(const Variable *) override;
void visit(const Add *) override;
void visit(const Sub *) override;
void visit(const Mul *) override;
void visit(const Div *) override;
void visit(const Mod *) override;
void visit(const Min *) override;
void visit(const Max *) override;
void visit(const EQ *) override;
void visit(const NE *) override;
void visit(const LT *) override;
void visit(const LE *) override;
void visit(const GT *) override;
void visit(const GE *) override;
void visit(const And *) override;
void visit(const Or *) override;
void visit(const Not *) override;
void visit(const Select *) override;
void visit(const Load *) override;
void visit(const Ramp *) override;
void visit(const Broadcast *) override;
void visit(const Call *) override;
void visit(const Let *) override;
void visit(const LetStmt *) override;
void visit(const AssertStmt *) override;
void visit(const ProducerConsumer *) override;
void visit(const For *) override;
void visit(const Store *) override;
void visit(const Provide *) override;
void visit(const Allocate *) override;
void visit(const Free *) override;
void visit(const Realize *) override;
void visit(const Block *) override;
void visit(const IfThenElse *) override;
void visit(const Evaluate *) override;
void visit(const Shuffle *) override;
void visit(const VectorReduce *) override;
void visit(const Prefetch *) override;
void visit(const Acquire *) override;
void visit(const Fork *) override;
void visit(const Atomic *) override;
// @}
};
/** A visitor/mutator capable of passing arbitrary arguments to the
* visit methods using CRTP and returning any types from them. All
* Expr visitors must have the same signature, and all Stmt visitors
* must have the same signature. Does not have default implementations
* of the visit methods. */
template<typename T, typename ExprRet, typename StmtRet>
class VariadicVisitor {
private:
template<typename... Args>
ExprRet dispatch_expr(const BaseExprNode *node, Args &&...args) {
if (node == nullptr) {
return ExprRet{};
}
switch (node->node_type) {
case IRNodeType::IntImm:
return ((T *)this)->visit((const IntImm *)node, std::forward<Args>(args)...);
case IRNodeType::UIntImm:
return ((T *)this)->visit((const UIntImm *)node, std::forward<Args>(args)...);
case IRNodeType::FloatImm:
return ((T *)this)->visit((const FloatImm *)node, std::forward<Args>(args)...);
case IRNodeType::StringImm:
return ((T *)this)->visit((const StringImm *)node, std::forward<Args>(args)...);
case IRNodeType::Broadcast:
return ((T *)this)->visit((const Broadcast *)node, std::forward<Args>(args)...);
case IRNodeType::Cast:
return ((T *)this)->visit((const Cast *)node, std::forward<Args>(args)...);
case IRNodeType::Variable:
return ((T *)this)->visit((const Variable *)node, std::forward<Args>(args)...);
case IRNodeType::Add:
return ((T *)this)->visit((const Add *)node, std::forward<Args>(args)...);
case IRNodeType::Sub:
return ((T *)this)->visit((const Sub *)node, std::forward<Args>(args)...);
case IRNodeType::Mod:
return ((T *)this)->visit((const Mod *)node, std::forward<Args>(args)...);
case IRNodeType::Mul:
return ((T *)this)->visit((const Mul *)node, std::forward<Args>(args)...);
case IRNodeType::Div:
return ((T *)this)->visit((const Div *)node, std::forward<Args>(args)...);
case IRNodeType::Min:
return ((T *)this)->visit((const Min *)node, std::forward<Args>(args)...);
case IRNodeType::Max:
return ((T *)this)->visit((const Max *)node, std::forward<Args>(args)...);
case IRNodeType::EQ:
return ((T *)this)->visit((const EQ *)node, std::forward<Args>(args)...);
case IRNodeType::NE:
return ((T *)this)->visit((const NE *)node, std::forward<Args>(args)...);
case IRNodeType::LT:
return ((T *)this)->visit((const LT *)node, std::forward<Args>(args)...);
case IRNodeType::LE:
return ((T *)this)->visit((const LE *)node, std::forward<Args>(args)...);
case IRNodeType::GT:
return ((T *)this)->visit((const GT *)node, std::forward<Args>(args)...);
case IRNodeType::GE:
return ((T *)this)->visit((const GE *)node, std::forward<Args>(args)...);
case IRNodeType::And:
return ((T *)this)->visit((const And *)node, std::forward<Args>(args)...);
case IRNodeType::Or:
return ((T *)this)->visit((const Or *)node, std::forward<Args>(args)...);
case IRNodeType::Not:
return ((T *)this)->visit((const Not *)node, std::forward<Args>(args)...);
case IRNodeType::Select:
return ((T *)this)->visit((const Select *)node, std::forward<Args>(args)...);
case IRNodeType::Load:
return ((T *)this)->visit((const Load *)node, std::forward<Args>(args)...);
case IRNodeType::Ramp:
return ((T *)this)->visit((const Ramp *)node, std::forward<Args>(args)...);
case IRNodeType::Call:
return ((T *)this)->visit((const Call *)node, std::forward<Args>(args)...);
case IRNodeType::Let:
return ((T *)this)->visit((const Let *)node, std::forward<Args>(args)...);
case IRNodeType::Shuffle:
return ((T *)this)->visit((const Shuffle *)node, std::forward<Args>(args)...);
case IRNodeType::VectorReduce:
return ((T *)this)->visit((const VectorReduce *)node, std::forward<Args>(args)...);
// Explicitly list the Stmt types rather than using a
// default case so that when new IR nodes are added we
// don't miss them here.
case IRNodeType::LetStmt:
case IRNodeType::AssertStmt:
case IRNodeType::ProducerConsumer:
case IRNodeType::For:
case IRNodeType::Acquire:
case IRNodeType::Store:
case IRNodeType::Provide:
case IRNodeType::Allocate:
case IRNodeType::Free:
case IRNodeType::Realize:
case IRNodeType::Block:
case IRNodeType::Fork:
case IRNodeType::IfThenElse:
case IRNodeType::Evaluate:
case IRNodeType::Prefetch:
case IRNodeType::Atomic:
internal_error << "Unreachable";
}
return ExprRet{};
}
template<typename... Args>
StmtRet dispatch_stmt(const BaseStmtNode *node, Args &&...args) {
if (node == nullptr) {
return StmtRet{};
}
switch (node->node_type) {
case IRNodeType::IntImm:
case IRNodeType::UIntImm:
case IRNodeType::FloatImm:
case IRNodeType::StringImm:
case IRNodeType::Broadcast:
case IRNodeType::Cast:
case IRNodeType::Variable:
case IRNodeType::Add:
case IRNodeType::Sub:
case IRNodeType::Mod:
case IRNodeType::Mul:
case IRNodeType::Div:
case IRNodeType::Min:
case IRNodeType::Max:
case IRNodeType::EQ:
case IRNodeType::NE:
case IRNodeType::LT:
case IRNodeType::LE:
case IRNodeType::GT:
case IRNodeType::GE:
case IRNodeType::And:
case IRNodeType::Or:
case IRNodeType::Not:
case IRNodeType::Select:
case IRNodeType::Load:
case IRNodeType::Ramp:
case IRNodeType::Call:
case IRNodeType::Let:
case IRNodeType::Shuffle:
case IRNodeType::VectorReduce:
internal_error << "Unreachable";
break;
case IRNodeType::LetStmt:
return ((T *)this)->visit((const LetStmt *)node, std::forward<Args>(args)...);
case IRNodeType::AssertStmt:
return ((T *)this)->visit((const AssertStmt *)node, std::forward<Args>(args)...);
case IRNodeType::ProducerConsumer:
return ((T *)this)->visit((const ProducerConsumer *)node, std::forward<Args>(args)...);
case IRNodeType::For:
return ((T *)this)->visit((const For *)node, std::forward<Args>(args)...);
case IRNodeType::Acquire:
return ((T *)this)->visit((const Acquire *)node, std::forward<Args>(args)...);
case IRNodeType::Store:
return ((T *)this)->visit((const Store *)node, std::forward<Args>(args)...);
case IRNodeType::Provide:
return ((T *)this)->visit((const Provide *)node, std::forward<Args>(args)...);
case IRNodeType::Allocate:
return ((T *)this)->visit((const Allocate *)node, std::forward<Args>(args)...);
case IRNodeType::Free:
return ((T *)this)->visit((const Free *)node, std::forward<Args>(args)...);
case IRNodeType::Realize:
return ((T *)this)->visit((const Realize *)node, std::forward<Args>(args)...);
case IRNodeType::Block:
return ((T *)this)->visit((const Block *)node, std::forward<Args>(args)...);
case IRNodeType::Fork:
return ((T *)this)->visit((const Fork *)node, std::forward<Args>(args)...);
case IRNodeType::IfThenElse:
return ((T *)this)->visit((const IfThenElse *)node, std::forward<Args>(args)...);
case IRNodeType::Evaluate:
return ((T *)this)->visit((const Evaluate *)node, std::forward<Args>(args)...);
case IRNodeType::Prefetch:
return ((T *)this)->visit((const Prefetch *)node, std::forward<Args>(args)...);
case IRNodeType::Atomic:
return ((T *)this)->visit((const Atomic *)node, std::forward<Args>(args)...);
}
return StmtRet{};
}
public:
template<typename... Args>
HALIDE_ALWAYS_INLINE StmtRet dispatch(const Stmt &s, Args &&...args) {
return dispatch_stmt(s.get(), std::forward<Args>(args)...);
}
template<typename... Args>
HALIDE_ALWAYS_INLINE StmtRet dispatch(Stmt &&s, Args &&...args) {
return dispatch_stmt(s.get(), std::forward<Args>(args)...);
}
template<typename... Args>
HALIDE_ALWAYS_INLINE ExprRet dispatch(const Expr &e, Args &&...args) {
return dispatch_expr(e.get(), std::forward<Args>(args)...);
}
template<typename... Args>
HALIDE_ALWAYS_INLINE ExprRet dispatch(Expr &&e, Args &&...args) {
return dispatch_expr(e.get(), std::forward<Args>(args)...);
}
};
} // namespace Internal
} // namespace Halide
#endif
