com.android.dx.rop.code

Interface TranslationAdvice

All Known Implementing Classes:

ConservativeTranslationAdvice, DexTranslationAdvice

public interface TranslationAdvice

Interface for "advice" passed from the late stage of translation back to the early stage. This allows for the final target architecture to exert its influence early in the translation process without having the early stage code be explicitly tied to the target.

Method Summary

Modifier and Type	Method and Description
int	getMaxOptimalRegisterCount() Gets the maximum register width that can be represented optimally.
boolean	hasConstantOperation(Rop opcode, RegisterSpec sourceA, RegisterSpec sourceB) Returns an indication of whether the target can directly represent an instruction with the given opcode operating on the given arguments, where the last source argument is used as a constant.
boolean	requiresSourcesInOrder(Rop opcode, RegisterSpecList sources) Returns true if the translation target requires the sources of the specified opcode to be in order and contiguous (eg, for an invoke-range)

Method Detail

hasConstantOperation

boolean hasConstantOperation(Rop opcode,
                             RegisterSpec sourceA,
                             RegisterSpec sourceB)

Returns an indication of whether the target can directly represent an instruction with the given opcode operating on the given arguments, where the last source argument is used as a constant. (That is, the last argument must have a type which indicates it is a known constant.) The instruction associated must have exactly two sources.

Parameters:

opcode - non-null; the opcode

sourceA - non-null; the first source

sourceB - non-null; the second source

Returns:

true iff the target can represent the operation using a constant for the last argument

requiresSourcesInOrder

boolean requiresSourcesInOrder(Rop opcode,
                               RegisterSpecList sources)

Returns true if the translation target requires the sources of the specified opcode to be in order and contiguous (eg, for an invoke-range)

Parameters:

opcode - non-null; opcode

sources - non-null; source list

Returns:

true iff the target requires the sources to be in order and contiguous.

getMaxOptimalRegisterCount

int getMaxOptimalRegisterCount()

Gets the maximum register width that can be represented optimally. For example, Dex bytecode does not have instruction forms that take register numbers larger than 15 for all instructions so DexTranslationAdvice returns 15 here.

Returns:

register count noted above