Inheritance diagram for P4::KeySideEffect:

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Public Member Functions
	KeySideEffect (ReferenceMap refMap, TypeMap typeMap, std::set< const IR::P4Table * > *invokedInKey)

virtual const IR::Node *	doStatement (const IR::Statement statement, const IR::Expression expression)

const IR::Node *	postorder (IR::AssignmentStatement *statement) override

const IR::Node *	postorder (IR::IfStatement *statement) override

const IR::Node *	postorder (IR::KeyElement *element) override

const IR::Node *	postorder (IR::MethodCallStatement *statement) override

const IR::Node *	postorder (IR::P4Table *table) override

const IR::Node *	postorder (IR::SwitchStatement *statement) override

const IR::Node *	preorder (IR::Key *key) override

const IR::Node *	preorder (IR::P4Table *table) override

Protected Attributes
std::set< const IR::P4Table * > *	invokedInKey

ReferenceMap *	refMap

std::map< const IR::P4Table , TableInsertions >	toInsert

TypeMap *	typeMap

Detailed Description

This pass is an adaptation of the midend code SimplifyKey. If a key computation involves side effects then all key field computations are lifted prior to the table application. We need to lift all key field computations since the order of side-effects needs to be preserved.

table t {
  key = { a: exact,
          f() : exact; }
  ...
}
apply {
  t.apply();
}

is transformed to

bit<32> key_0;
bit<32> key_1;
table t {
  key = { key_0 : exact;
          key_1 : exact; }
  ...
}
apply {
  key_0 = a;
  key_1 = f();
  t.apply();
}

Precondition: none

Postcondition: all complex table key expressions are replaced with a simpler expression.

Public Member Functions

Protected Attributes

Detailed Description