harpoon.IR.Quads
Class Qop

java.lang.Object
  harpoon.IR.Quads.Qop

Direct Known Subclasses:

LQop

public abstract class Qop
extends Object

Qop is an enumerated type for the various kinds of OPER opcodes. The basic rationale is to use a minimal set of opcodes to simplify later analysis.

Note that (x - y) is uniformly expressed as (x + (-y)), and that (~x) is typically expressed (compiler-dependent) as (x ^ (-1)). There is also a minimal set of comparison operations; all other comparisons can be synthesized from the ones present. Note that floating-point (float/double) comparisons have special behaviors when NaN is an operand. Note also that one each of IAND/IOR and LAND/LOR could be removed, but the translation involved too many steps to be deemed worthwhile.

Version:

$Id: Qop.java,v 1.2 2002/02/25 21:05:12 cananian Exp $

Author:

C. Scott Ananian <cananian@alumni.princeton.edu>

Field Summary

static int	ACMPEQ Compares references for equality.
static int	D2F Converts a double to a float.
static int	D2I Converts a double to an int.
static int	D2L Converts a double to a long.
static int	DADD Computes the sum of two double values.
static int	DCMPEQ Evaluates to true if double values are equal and neither is NaN, or false otherwise.
static int	DCMPGE Evaluates to true if first double value is greater than or equal to the second double value and neither is NaN, or false otherwise.
static int	DCMPGT Evaluates to true if first double value is greater than the second double value and neither is NaN, or false otherwise.
static int	DDIV Computes the quotient of two double values.
static int	DMUL Computes the product of two double values.
static int	DNEG Computes the negation of a double value.
static int	DREM Computes the remainder of two double values.
static int	F2D Converts a float to a double.
static int	F2I Converts a float to an int.
static int	F2L Converts a float to a long.
static int	FADD Computes the sum of two float values.
static int	FCMPEQ Evaluates to true if the float values are equal and neither is NaN, or false otherwise.
static int	FCMPGE Evaluates to true if the first float value is greater than or equal to the second float value and neither is NaN, or false otherwise.
static int	FCMPGT Evaluates to true if the first float value is greater than the second float value and neither is NaN, or false otherwise.
static int	FDIV Computes the quotient of two float values.
static int	FMUL Computes the product of two float values.
static int	FNEG Computes the negation of a float value.
static int	FREM Computes the remainder of two float values.
static int	I2B Converts an int to a byte.
static int	I2C Converts an int to a character.
static int	I2D Converts an int to a double.
static int	I2F Converts an int to a float.
static int	I2L Converts an int to a long.
static int	I2S Converts an int to a short.
static int	IADD Computes the sum of two int values.
static int	IAND Computes the binary-AND of two int values.
static int	ICMPEQ Evaluates to true if the two int values are equal, or false otherwise.
static int	ICMPGT Evalutates to true if the first int value is greater than the second int value, or false otherwise.
static int	IDIV Computes the int quotient of two int values.
static int	IMUL Computes the product of two int values.
static int	INEG Computes the negation of an int value.
static int	IOR Computes the binary-OR of two int values.
static int	IREM Computes the remainder of two int values.
static int	ISHL Computes the value of the first int value shifted left by the number of bits specified in the low five bits of the second int value.
static int	ISHR Computes the value of the first int value shifted right with sign extension by the number of bits specified in the low five bits of the second int value.
static int	IUSHR Computes the value of the first int value shifted right without sign extension by the number of bits specified in the low five bits of the second int value.
static int	IXOR Computes the binary-XOR of two int values.
static int	L2D Converts a long to a double.
static int	L2F Converts a long to a float.
static int	L2I Converts a long to an int.
static int	LADD Computes the sum of two long values.
static int	LAND Computes the binary-AND of two long values.
static int	LCMPEQ Evaluates to true if the two long values are equal, or false otherwise.
static int	LCMPGT Evaluates to true if the first long value is greater than the second, or false otherwise.
static int	LDIV Computes the quotient of two long values.
static int	LMUL Computes the product of two long values.
static int	LNEG Computes the negation of a long value.
static int	LOR Computes the binary-OR of two long values.
static int	LREM Computes the remainder of two long values.
static int	LSHL Computes the value of the first long value shifted left by the number of bits specified in the low six bits of the second int value.
static int	LSHR Computes the value of the first long value shifted right with sign extension by the number of bits specified in the low six bits of the second int value.
static int	LUSHR Computes the value of the first long value shifted right without sign extension by the number of bits specified in the low six bits of the second int value.
static int	LXOR Computes the binary-XOR of two long values.

Constructor Summary

Qop()

Method Summary

static Object	evaluate(int opc, Object[] opd) Evaluates a constant value for the result of an OPER, given constant values for the operands.
static int	forString(String op) Returns the enumerated Qop that corresponds to a given descriptive string.
static boolean	isValid(int v) Determines if a given Qop value is valid.
static HClass	resultType(int v) Determines the result type of an OPER.
static String	toString(int v) Converts the enumerated Qop value to a descriptive string.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

ACMPEQ

public static final int ACMPEQ

Compares references for equality.

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Constant Field Values

D2F

public static final int D2F

Converts a double to a float.

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Constant Field Values

D2I

public static final int D2I

Converts a double to an int.

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Constant Field Values

D2L

public static final int D2L

Converts a double to a long.

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Constant Field Values

DADD

public static final int DADD

Computes the sum of two double values.

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Constant Field Values

DCMPEQ

public static final int DCMPEQ

Evaluates to true if double values are equal and neither is NaN, or false otherwise.

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Constant Field Values

DCMPGE

public static final int DCMPGE

Evaluates to true if first double value is greater than or equal to the second double value and neither is NaN, or false otherwise.

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Constant Field Values

DCMPGT

public static final int DCMPGT

Evaluates to true if first double value is greater than the second double value and neither is NaN, or false otherwise.

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Constant Field Values

DDIV

public static final int DDIV

Computes the quotient of two double values.

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Constant Field Values

DMUL

public static final int DMUL

Computes the product of two double values.

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Constant Field Values

DNEG

public static final int DNEG

Computes the negation of a double value.

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Constant Field Values

DREM

public static final int DREM

Computes the remainder of two double values.

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Constant Field Values

F2D

public static final int F2D

Converts a float to a double.

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Constant Field Values

F2I

public static final int F2I

Converts a float to an int.

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Constant Field Values

F2L

public static final int F2L

Converts a float to a long.

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Constant Field Values

FADD

public static final int FADD

Computes the sum of two float values.

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Constant Field Values

FCMPEQ

public static final int FCMPEQ

Evaluates to true if the float values are equal and neither is NaN, or false otherwise.

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Constant Field Values

FCMPGE

public static final int FCMPGE

Evaluates to true if the first float value is greater than or equal to the second float value and neither is NaN, or false otherwise.

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Constant Field Values

FCMPGT

public static final int FCMPGT

Evaluates to true if the first float value is greater than the second float value and neither is NaN, or false otherwise.

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Constant Field Values

FDIV

public static final int FDIV

Computes the quotient of two float values.

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Constant Field Values

FMUL

public static final int FMUL

Computes the product of two float values.

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Constant Field Values

FNEG

public static final int FNEG

Computes the negation of a float value.

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Constant Field Values

FREM

public static final int FREM

Computes the remainder of two float values.

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Constant Field Values

I2B

public static final int I2B

Converts an int to a byte. Result is still int type, but it is truncated to 8 bits, then sign-extended.

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Constant Field Values

I2C

public static final int I2C

Converts an int to a character. Result is still int type, but is truncated to 16 bits. No sign extension.

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Constant Field Values

I2D

public static final int I2D

Converts an int to a double.

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Constant Field Values

I2F

public static final int I2F

Converts an int to a float.

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Constant Field Values

I2L

public static final int I2L

Converts an int to a long.

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Constant Field Values

I2S

public static final int I2S

Converts an int to a short. Result is still int type, but is truncated to 16 bits, then sign extended.

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Constant Field Values

IADD

public static final int IADD

Computes the sum of two int values.

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Constant Field Values

IAND

public static final int IAND

Computes the binary-AND of two int values.

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Constant Field Values

ICMPEQ

public static final int ICMPEQ

Evaluates to true if the two int values are equal, or false otherwise.

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Constant Field Values

ICMPGT

public static final int ICMPGT

Evalutates to true if the first int value is greater than the second int value, or false otherwise.

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Constant Field Values

IDIV

public static final int IDIV

Computes the int quotient of two int values.

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Constant Field Values

IMUL

public static final int IMUL

Computes the product of two int values.

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Constant Field Values

INEG

public static final int INEG

Computes the negation of an int value.

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Constant Field Values

IOR

public static final int IOR

Computes the binary-OR of two int values.

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Constant Field Values

IREM

public static final int IREM

Computes the remainder of two int values.

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Constant Field Values

ISHL

public static final int ISHL

Computes the value of the first int value shifted left by the number of bits specified in the low five bits of the second int value. That is, ( 1 << 34 ) == 4. Also, (x << -1) == (x << 31).

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Constant Field Values

ISHR

public static final int ISHR

Computes the value of the first int value shifted right with sign extension by the number of bits specified in the low five bits of the second int value. That is, ( -4 >> 33 ) == -2. Also, (x >> -1) == (x >> 31).

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Constant Field Values

IUSHR

public static final int IUSHR

Computes the value of the first int value shifted right without sign extension by the number of bits specified in the low five bits of the second int value. That is, ( -4 >>> 30) == 3. Also, (x >>> -1) == (x >>> 31).

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Constant Field Values

IXOR

public static final int IXOR

Computes the binary-XOR of two int values.

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Constant Field Values

L2D

public static final int L2D

Converts a long to a double.

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Constant Field Values

L2F

public static final int L2F

Converts a long to a float.

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Constant Field Values

L2I

public static final int L2I

Converts a long to an int.

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Constant Field Values

LADD

public static final int LADD

Computes the sum of two long values.

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Constant Field Values

LAND

public static final int LAND

Computes the binary-AND of two long values.

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Constant Field Values

LCMPEQ

public static final int LCMPEQ

Evaluates to true if the two long values are equal, or false otherwise.

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Constant Field Values

LCMPGT

public static final int LCMPGT

Evaluates to true if the first long value is greater than the second, or false otherwise.

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Constant Field Values

LDIV

public static final int LDIV

Computes the quotient of two long values.

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Constant Field Values

LMUL

public static final int LMUL

Computes the product of two long values.

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Constant Field Values

LNEG

public static final int LNEG

Computes the negation of a long value.

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Constant Field Values

LOR

public static final int LOR

Computes the binary-OR of two long values.

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Constant Field Values

LREM

public static final int LREM

Computes the remainder of two long values.

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Constant Field Values

LSHL

public static final int LSHL

Computes the value of the first long value shifted left by the number of bits specified in the low six bits of the second int value. That is, (1 << 66) == 4. Also, (x << -1) == (x << 63).

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Constant Field Values

LSHR

public static final int LSHR

Computes the value of the first long value shifted right with sign extension by the number of bits specified in the low six bits of the second int value. That is, (-4 >> 65) == -2. Also, (x >> -1) == (x >> 63).

See Also:

Constant Field Values

LUSHR

public static final int LUSHR

Computes the value of the first long value shifted right without sign extension by the number of bits specified in the low six bits of the second int value. That is, (-4 >>> 62) == 3. Also, (x >>> -1) == (x >>> 63).

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Constant Field Values

LXOR

public static final int LXOR

Computes the binary-XOR of two long values.

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Constant Field Values

Constructor Detail

Qop

public Qop()

Method Detail

isValid

public static boolean isValid(int v)

Determines if a given Qop value is valid.

toString

public static String toString(int v)

Converts the enumerated Qop value to a descriptive string.

forString

public static int forString(String op)

Returns the enumerated Qop that corresponds to a given descriptive string.

resultType

public static HClass resultType(int v)

Determines the result type of an OPER.

evaluate

public static Object evaluate(int opc,
                              Object[] opd)

Evaluates a constant value for the result of an OPER, given constant values for the operands.