jminusminus

Interface JLhs

All Known Implementing Classes:

JArrayExpression, JFieldSelection, JVariable

interface JLhs

The type of any expression that can appear on the lhs of an assignment statement, i.e., JVariable, JFieldSelection, JArrayExpression.

Method Summary

Methods

Modifier and Type	Method and Description
JExpression	analyzeLhs(Context context) Analyze the lhs of an assignment.
void	codegenDuplicateRvalue(CLEmitter output) Generate the code required for duplicating the Rvalue that is on the stack becuase it is to be used in a surrounding expression, as in a[i] = x = or x = y--.
void	codegenLoadLhsLvalue(CLEmitter output) The up front code necessary for implementing an assignment; it generates code to load onto the stack any part of the lhs variable that must be there.
void	codegenLoadLhsRvalue(CLEmitter output) Generate the code required for loading an Rvalue for this variable, as in a +=.
void	codegenStore(CLEmitter output) Generate the code required for doing the actual assignment.

Method Detail

analyzeLhs

JExpression analyzeLhs(Context context)

Analyze the lhs of an assignment. This is very much like analyze() but perhaps a little more selective here and there.

Parameters:

context - context in which names are resolved.

Returns:

the analyzed (and possibly rewritten) AST subtree.

codegenLoadLhsLvalue

void codegenLoadLhsLvalue(CLEmitter output)

The up front code necessary for implementing an assignment; it generates code to load onto the stack any part of the lhs variable that must be there. For example, in a[i] = x, code must be generated to load the array (a) and the index (i).

Parameters:

output - the code emitter (basically an abstraction for producing the .class file).

codegenLoadLhsRvalue

void codegenLoadLhsRvalue(CLEmitter output)

Generate the code required for loading an Rvalue for this variable, as in a +=.

Parameters:

output - the code emitter (basically an abstraction for producing the .class file).

codegenDuplicateRvalue

void codegenDuplicateRvalue(CLEmitter output)

Generate the code required for duplicating the Rvalue that is on the stack becuase it is to be used in a surrounding expression, as in a[i] = x = or x = y--.

Parameters:

output - the code emitter (basically an abstraction for producing the .class file).

codegenStore

void codegenStore(CLEmitter output)

Generate the code required for doing the actual assignment.

Parameters:

output - the code emitter (basically an abstraction for producing the .class file).