Package ghidra.pcode.emu.jit.gen.op

Enum Class CallOtherOpGen

java.lang.Object

java.lang.Enum<CallOtherOpGen>

ghidra.pcode.emu.jit.gen.op.CallOtherOpGen

All Implemented Interfaces:

OpGen<JitCallOtherOpIf>, Serializable, Comparable<CallOtherOpGen>, Constable

public enum CallOtherOpGen
extends Enum<CallOtherOpGen>
implements OpGen<JitCallOtherOpIf>

The generator for a callother.

The checks if Direct invocation is possible. If so, it emits code using genRunDirectStrategy(Emitter, Local, JitCodeGenerator, JitCallOtherOpIf, JitBlock, Scope). If not, it emits code using genRunRetirementStrategy(Emitter, Local, JitCodeGenerator, PcodeOp, JitBlock, PcodeUseropDefinition). Direct invocation is possible when the userop is functional and all of its parameters and return type have a supported primitive type. (char is not supported.) Regarding the invocation strategies, see JitDataFlowUseropLibrary and note that the Inline strategy is already handled by this point.

For the Standard strategy, we emit code to retire the program counter, decode context, and all live variables. We then request a field to hold the PcodeOp.CALLOTHER p-code op and the userop, and emit code to load them. We then emit code to invoke JitCompiledPassage.invokeUserop(PcodeUseropDefinition, PcodeOp). The userop definition handles retrieving all of its inputs and writing the output, directly to the state. Thus, we now need only to emit code to re-birth all the live variables. If any errors occur, execution is interrupted as usual, and our state is consistent.

For the Direct strategy, we wish to avoid retirement and re-birth, so we request an ExceptionHandler. We request a field for the userop, just as in the Standard strategy, but we emit code to invoke PcodeUseropLibrary.PcodeUseropDefinition.getDefiningLibrary() instead. We can use PcodeUseropLibrary.PcodeUseropDefinition.getJavaMethod() at generation time to reflect its Java definition. We then emit code to cast the library and load each of the operands onto the JVM stack. We then emit the invocation of the Java method, guarded by the exception handler. We then have to consider whether the userop has an output operand and whether its definition returns a value. If both are true, we emit code to write the result. If neither is true, we're done. If a result is returned, but no output operand is provided, we must still emit a pop.

Nested Class Summary

Nested classes/interfaces inherited from class java.lang.Enum

Enum.EnumDesc<E extends Enum<E>>

Nested classes/interfaces inherited from interface ghidra.pcode.emu.jit.gen.op.OpGen

OpGen.DeadOpResult, OpGen.LiveOpResult, OpGen.OpResult

Enum Constant Summary

Enum Constants

Enum Constant	Description
GEN	The generator singleton

Method Summary

Modifier and Type	Method	Description
static boolean	canDoDirectInvocation(JitCallOtherOpIf op)	Check if the Direct invocation strategy is applicable (see class documentation)
<THIS extends JitCompiledPassage> OpGen.OpResult	genRun(Emitter<Emitter.Bot> em, Local<Types.TRef<THIS>> localThis, Local<Types.TInt> localCtxmod, Methods.RetReq<Types.TRef<JitCompiledPassage.EntryPoint>> retReq, JitCodeGenerator<THIS> gen, JitCallOtherOpIf op, JitControlFlowModel.JitBlock block, Scope scope)	Emit bytecode into the run method.
static <THIS extends JitCompiledPassage, LIB extends PcodeUseropLibrary<?>> OpGen.OpResult	genRunDirectStrategy(Emitter<Emitter.Bot> em, Local<Types.TRef<THIS>> localThis, JitCodeGenerator<THIS> gen, JitCallOtherOpIf op, JitControlFlowModel.JitBlock block, Scope scope)	Emit code to implement the Direct strategy (see the class documentation)
static <THIS extends JitCompiledPassage> OpGen.OpResult	genRunRetirementStrategy(Emitter<Emitter.Bot> em, Local<Types.TRef<THIS>> localThis, JitCodeGenerator<THIS> gen, PcodeOp op, JitControlFlowModel.JitBlock block, PcodeUseropLibrary.PcodeUseropDefinition<?> userop)	Emit code to implement the Standard strategy (see the class documentation)
static CallOtherOpGen	valueOf(String name)	Returns the enum constant of this class with the specified name.
static CallOtherOpGen[]	values()	Returns an array containing the constants of this enum class, in the order they are declared.

Methods inherited from class java.lang.Enum

clone, compareTo, describeConstable, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Enum Constant Details

GEN

public static final CallOtherOpGen GEN

The generator singleton

Method Details

values

public static CallOtherOpGen[] values()

Returns an array containing the constants of this enum class, in the order they are declared.

Returns:

an array containing the constants of this enum class, in the order they are declared

valueOf

public static CallOtherOpGen valueOf(String name)

Returns the enum constant of this class with the specified name. The string must match exactly an identifier used to declare an enum constant in this class. (Extraneous whitespace characters are not permitted.)

Parameters:

name - the name of the enum constant to be returned.

Returns:

the enum constant with the specified name

Throws:

IllegalArgumentException - if this enum class has no constant with the specified name

NullPointerException - if the argument is null

genRunRetirementStrategy

public static <THIS extends JitCompiledPassage>
OpGen.OpResult genRunRetirementStrategy(Emitter<Emitter.Bot> em,
 Local<Types.TRef<THIS>> localThis,
 JitCodeGenerator<THIS> gen,
 PcodeOp op,
 JitControlFlowModel.JitBlock block,
 PcodeUseropLibrary.PcodeUseropDefinition<?> userop)

Emit code to implement the Standard strategy (see the class documentation)

Type Parameters:

THIS - the type of the generated passage

Parameters:

em - the emitter typed with the empty stack

localThis - a handle to the local holding the this reference

gen - the code generator

op - the p-code op

block - the block containing the op

userop - the userop definition, wrapped by the JitDataFlowUseropLibrary

Returns:

the result of emitting the userop's bytecode

genRunDirectStrategy

public static <THIS extends JitCompiledPassage,
LIB extends PcodeUseropLibrary<?>>
OpGen.OpResult genRunDirectStrategy(Emitter<Emitter.Bot> em,
 Local<Types.TRef<THIS>> localThis,
 JitCodeGenerator<THIS> gen,
 JitCallOtherOpIf op,
 JitControlFlowModel.JitBlock block,
 Scope scope)

Emit code to implement the Direct strategy (see the class documentation)

Type Parameters:

THIS - the type of the generated passage

Parameters:

em - the emitter typed with the empty stack

localThis - a handle to the local holding the this reference

gen - the code generator

op - the p-code op use-def node

block - the block containing the op

scope - a scope for generating temporary local storage

Returns:

the result of emitting the userop's bytecode

canDoDirectInvocation

public static boolean canDoDirectInvocation(JitCallOtherOpIf op)

Check if the Direct invocation strategy is applicable (see class documentation)

Parameters:

op - the p-code op use-def node

Returns:

true if applicable

genRun

public <THIS extends JitCompiledPassage>
OpGen.OpResult genRun(Emitter<Emitter.Bot> em,
 Local<Types.TRef<THIS>> localThis,
 Local<Types.TInt> localCtxmod,
 Methods.RetReq<Types.TRef<JitCompiledPassage.EntryPoint>> retReq,
 JitCodeGenerator<THIS> gen,
 JitCallOtherOpIf op,
 JitControlFlowModel.JitBlock block,
 Scope scope)

Description copied from interface: OpGen

Emit bytecode into the run method.

This method must emit the code needed to load any input operands, convert them to the appropriate type, perform the actual operation, and then if applicable, store the output operand. The implementations should delegate to JitCodeGenerator.genReadToStack(Emitter, Local, JitVal, ghidra.pcode.emu.jit.analysis.JitType.SimpleJitType, Ext), JitCodeGenerator.genWriteFromStack(Emitter, Local, JitVar, ghidra.pcode.emu.jit.analysis.JitType.SimpleJitType, Ext, Scope) or similar for mp-int types.

Specified by:

genRun in interface OpGen<JitCallOtherOpIf>

Type Parameters:

THIS - the type of the generated passage

Parameters:

em - the emitter typed with the empty stack

localThis - a handle to the local holding the this reference

localCtxmod - a handle to the local holding ctxmod

retReq - an indication of what must be returned by this JitCompiledPassage.run(int) method.

gen - the code generator

op - the p-code op (use-def node) to translate

block - the basic block containing the p-code op

scope - a scope for generating temporary local storage

Returns:

the result of emitting the p-code op's bytecode