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

Enum Class IntCarryOpGen

java.lang.Object

java.lang.Enum<IntCarryOpGen>

ghidra.pcode.emu.jit.gen.op.IntCarryOpGen

All Implemented Interfaces:

BinOpGen<JitIntCarryOp>, OpGen<JitIntCarryOp>, Serializable, Comparable<IntCarryOpGen>, Constable, org.objectweb.asm.Opcodes

public enum IntCarryOpGen
extends Enum<IntCarryOpGen>
implements BinOpGen<JitIntCarryOp>

The generator for a int_carry.

This uses the binary operator generator. First we have to consider which strategy we are going to use. If the p-code type is strictly smaller than its host JVM type, we can simply add the two operands and examine the next bit up. This is accomplished by emitting Opcodes.IADD or Opcodes.LADD, depending on the type, followed by a shift right and a mask.

If the p-code type exactly fits its host JVM type, we still add, but we will need to compare the result to one of the operands. Thus, we override afterLeft and emit code to duplicate the left operand. We can then add and invoke Integer.compareUnsigned(int, int) to determine whether there was overflow. If there was, then we know the carry bit would have been set. We can spare the conditional flow by just shifting the sign bit into the 1's place.

NOTE: The multi-precision integer parts of this are a work in progress.

Nested Class Summary

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

Enum.EnumDesc<E extends Enum<E>>

Enum Constant Summary

Enum Constants

Enum Constant	Description
GEN	The generator singleton

Field Summary

Fields inherited from interface org.objectweb.asm.Opcodes

AALOAD, AASTORE, ACC_ABSTRACT, ACC_ANNOTATION, ACC_BRIDGE, ACC_DEPRECATED, ACC_ENUM, ACC_FINAL, ACC_INTERFACE, ACC_MANDATED, ACC_MODULE, ACC_NATIVE, ACC_OPEN, ACC_PRIVATE, ACC_PROTECTED, ACC_PUBLIC, ACC_RECORD, ACC_STATIC, ACC_STATIC_PHASE, ACC_STRICT, ACC_SUPER, ACC_SYNCHRONIZED, ACC_SYNTHETIC, ACC_TRANSIENT, ACC_TRANSITIVE, ACC_VARARGS, ACC_VOLATILE, ACONST_NULL, ALOAD, ANEWARRAY, ARETURN, ARRAYLENGTH, ASM10_EXPERIMENTAL, ASM4, ASM5, ASM6, ASM7, ASM8, ASM9, ASTORE, ATHROW, BALOAD, BASTORE, BIPUSH, CALOAD, CASTORE, CHECKCAST, D2F, D2I, D2L, DADD, DALOAD, DASTORE, DCMPG, DCMPL, DCONST_0, DCONST_1, DDIV, DLOAD, DMUL, DNEG, DOUBLE, DREM, DRETURN, DSTORE, DSUB, DUP, DUP_X1, DUP_X2, DUP2, DUP2_X1, DUP2_X2, F_APPEND, F_CHOP, F_FULL, F_NEW, F_SAME, F_SAME1, F2D, F2I, F2L, FADD, FALOAD, FASTORE, FCMPG, FCMPL, FCONST_0, FCONST_1, FCONST_2, FDIV, FLOAD, FLOAT, FMUL, FNEG, FREM, FRETURN, FSTORE, FSUB, GETFIELD, GETSTATIC, GOTO, H_GETFIELD, H_GETSTATIC, H_INVOKEINTERFACE, H_INVOKESPECIAL, H_INVOKESTATIC, H_INVOKEVIRTUAL, H_NEWINVOKESPECIAL, H_PUTFIELD, H_PUTSTATIC, I2B, I2C, I2D, I2F, I2L, I2S, IADD, IALOAD, IAND, IASTORE, ICONST_0, ICONST_1, ICONST_2, ICONST_3, ICONST_4, ICONST_5, ICONST_M1, IDIV, IF_ACMPEQ, IF_ACMPNE, IF_ICMPEQ, IF_ICMPGE, IF_ICMPGT, IF_ICMPLE, IF_ICMPLT, IF_ICMPNE, IFEQ, IFGE, IFGT, IFLE, IFLT, IFNE, IFNONNULL, IFNULL, IINC, ILOAD, IMUL, INEG, INSTANCEOF, INTEGER, INVOKEDYNAMIC, INVOKEINTERFACE, INVOKESPECIAL, INVOKESTATIC, INVOKEVIRTUAL, IOR, IREM, IRETURN, ISHL, ISHR, ISTORE, ISUB, IUSHR, IXOR, JSR, L2D, L2F, L2I, LADD, LALOAD, LAND, LASTORE, LCMP, LCONST_0, LCONST_1, LDC, LDIV, LLOAD, LMUL, LNEG, LONG, LOOKUPSWITCH, LOR, LREM, LRETURN, LSHL, LSHR, LSTORE, LSUB, LUSHR, LXOR, MONITORENTER, MONITOREXIT, MULTIANEWARRAY, NEW, NEWARRAY, NOP, NULL, POP, POP2, PUTFIELD, PUTSTATIC, RET, RETURN, SALOAD, SASTORE, SIPUSH, SOURCE_DEPRECATED, SOURCE_MASK, SWAP, T_BOOLEAN, T_BYTE, T_CHAR, T_DOUBLE, T_FLOAT, T_INT, T_LONG, T_SHORT, TABLESWITCH, TOP, UNINITIALIZED_THIS, V_PREVIEW, V1_1, V1_2, V1_3, V1_4, V1_5, V1_6, V1_7, V1_8, V10, V11, V12, V13, V14, V15, V16, V17, V18, V19, V20, V21, V22, V23, V24, V9

Method Summary

Modifier and Type	Method	Description
JitType	afterLeft(JitCodeGenerator gen, JitIntCarryOp op, JitType lType, JitType rType, org.objectweb.asm.MethodVisitor rv)	Emit code between reading the left and right operands
JitType	generateBinOpRunCode(JitCodeGenerator gen, JitIntCarryOp op, JitControlFlowModel.JitBlock block, JitType lType, JitType rType, org.objectweb.asm.MethodVisitor rv)	Emit code for the binary operator
static IntCarryOpGen	valueOf(String name)	Returns the enum constant of this class with the specified name.
static IntCarryOpGen[]	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

Methods inherited from interface ghidra.pcode.emu.jit.gen.op.BinOpGen

generateRunCode

Methods inherited from interface ghidra.pcode.emu.jit.gen.op.OpGen

generateInitCode

Enum Constant Details

GEN

public static final IntCarryOpGen GEN

The generator singleton

Method Details

values

public static IntCarryOpGen[] 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 IntCarryOpGen 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

afterLeft

public JitType afterLeft(JitCodeGenerator gen,
 JitIntCarryOp op,
 JitType lType,
 JitType rType,
 org.objectweb.asm.MethodVisitor rv)

Description copied from interface: BinOpGen

Emit code between reading the left and right operands

This is invoked immediately after emitting code to push the left operand onto the stack, giving the implementation an opportunity to perform any manipulations of that operand necessary to set up the operation, before code to push the right operand is emitted.

Specified by:

afterLeft in interface BinOpGen<JitIntCarryOp>

Parameters:

gen - the code generator

op - the operator

lType - the actual type of the left operand

rType - the actual type of the right operand

rv - the method visitor

Returns:

the new actual type of the left operand

generateBinOpRunCode

public JitType generateBinOpRunCode(JitCodeGenerator gen,
 JitIntCarryOp op,
 JitControlFlowModel.JitBlock block,
 JitType lType,
 JitType rType,
 org.objectweb.asm.MethodVisitor rv)

Description copied from interface: BinOpGen

Emit code for the binary operator

At this point both operands are on the stack. After this returns, code to write the result from the stack into the destination operand will be emitted.

Specified by:

generateBinOpRunCode in interface BinOpGen<JitIntCarryOp>

Parameters:

gen - the code generator

op - the operator

block - the block containing the operator

lType - the actual type of the left operand

rType - the actual type of the right operand

rv - the method visitor

Returns:

the actual type of the result