[patterns-instanceof-primitive] RFR: 8303374: Compiler Implementation for Primitive types in patterns, instanceof, and switch [v2]

[Raffaello Giulietti]

On Fri, 10 Mar 2023 10:43:54 GMT, Aggelos Biboudis <abimpoudis at openjdk.org> wrote:

>> Prototype implementation for primitive types in patterns, instanceof, and switch.
>> 
>> draft JEP: https://openjdk.org/jeps/8288476
>> 
>> draft spec: https://cr.openjdk.org/~abimpoudis/instanceof/latest/
>
> Aggelos Biboudis has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Update int_float, long_float, long_double
>   
>   Co-authored-by: Angelos Bimpoudis <angelos.bimpoudis at oracle.com>
>   Co-authored-by: Raffaello Giulietti <raffaello.giulietti at oracle.com>

src/java.base/share/classes/java/lang/runtime/ExactnessMethods.java line 38:

> 36: 
> 37:     private ExactnessMethods() { }
> 38: 

Suggestion:

    public static boolean isNegativeZero(float n) {
        return Float.floatToIntRawBits(n) == Integer.MIN_VALUE;
    }

    public static boolean isNegativeZero(double n) {
        return Double.doubleToRawLongBits(n) == Long.MIN_VALUE;
    }

src/java.base/share/classes/java/lang/runtime/ExactnessMethods.java line 169:

> 167:      *
> 168:      * */
> 169:     public static boolean float_byte(float n)  {return Float.compare(n, (float)(byte)(n)) == 0;}

Suggestion:

    public static boolean float_byte(float n)  {
        return n == (float)(byte)n && !isNegativeZero(n);
    }

src/java.base/share/classes/java/lang/runtime/ExactnessMethods.java line 177:

> 175:      *
> 176:      * */
> 177:     public static boolean float_short(float n) {return Float.compare(n, (float)(short)(n)) == 0;}

Suggestion:

    public static boolean float_short(float n) {
        return n == (float)(short)n && !isNegativeZero(n);
    }

src/java.base/share/classes/java/lang/runtime/ExactnessMethods.java line 185:

> 183:      *
> 184:      * */
> 185:     public static boolean float_char(float n)  {return Float.compare(n, (float)(char)(n)) == 0;}

Suggestion:

    public static boolean float_char(float n)  {
        return n == (float)(char)n && !isNegativeZero(n);
    }

src/java.base/share/classes/java/lang/runtime/ExactnessMethods.java line 194:

> 192:      * */
> 193:     public static boolean float_int(float n) {
> 194:         return Double.compare((double)n, (double)((int)n)) == 0;

Suggestion:

        return n == (float)(int)n && n != 0x1p31f && !isNegativeZero(n);

src/java.base/share/classes/java/lang/runtime/ExactnessMethods.java line 208:

> 206:                 Float.compare(n, Float.NEGATIVE_INFINITY) == 0 ||
> 207:                 Float.compare(n, Float.POSITIVE_INFINITY) == 0) return false;
> 208:         return n == (long)n && n != (float)Long.MAX_VALUE + 1;

Suggestion:

        return n == (float)(long)n && n != 0x1p63f && !isNegativeZero(n);

src/java.base/share/classes/java/lang/runtime/ExactnessMethods.java line 217:

> 215:      *
> 216:      * */
> 217:     public static boolean double_byte(double n) {return Double.compare(n, (double)(byte)(n)) == 0;}

Suggestion:

    public static boolean double_byte(double n) {
        return n == (double)(byte)n && !isNegativeZero(n);
    }

src/java.base/share/classes/java/lang/runtime/ExactnessMethods.java line 225:

> 223:      *
> 224:      * */
> 225:     public static boolean double_short(double n){return Double.compare(n, (double)(short)(n)) == 0;}

Suggestion:

    public static boolean double_short(double n){
        return n == (double)(short)n && !isNegativeZero(n);
    }

src/java.base/share/classes/java/lang/runtime/ExactnessMethods.java line 233:

> 231:      *
> 232:      * */
> 233:     public static boolean double_char(double n) {return Double.compare(n, (double)(char)(n)) == 0;}

Suggestion:

    public static boolean double_char(double n) {
        return n == (double)(char)n && !isNegativeZero(n);
    }

src/java.base/share/classes/java/lang/runtime/ExactnessMethods.java line 241:

> 239:      *
> 240:      * */
> 241:     public static boolean double_int(double n)  {return Double.compare(n, (double)(int)(n)) == 0;}

Suggestion:

    public static boolean double_int(double n)  {
        return n == (double)(int)n && !isNegativeZero(n);    
    }

src/java.base/share/classes/java/lang/runtime/ExactnessMethods.java line 254:

> 252:                 Double.compare(n, Double.NEGATIVE_INFINITY) == 0 ||
> 253:                 Double.compare(n, Double.POSITIVE_INFINITY) == 0) return false;
> 254:         return n == (long)n && n != (double)Long.MAX_VALUE + 1;

Suggestion:

        return n == (double)(long)n && n != 0x1p63 && !isNegativeZero(n);

src/java.base/share/classes/java/lang/runtime/ExactnessMethods.java line 263:

> 261:      *
> 262:      * */
> 263:     public static boolean double_float(double n) {return Double.compare(n, (double)(float)(n)) == 0;}

Suggestion:

    public static boolean double_float(double n) {
        return n == (double)(float)n || n != n;
    }

-------------

PR: https://git.openjdk.org/amber/pull/91