Implement conversion between floating point numbers and unsigned integers

KT-27108

libraries/stdlib/unsigned/src/kotlin/UByte.kt

@@ -176,6 +176,11 @@ public inline class UByte @PublishedApi internal constructor(@PublishedApi inter
     @kotlin.internal.InlineOnly
     public inline fun toULong(): ULong = ULong(data.toLong() and 0xFF)
 
+    @kotlin.internal.InlineOnly
+    public inline fun toFloat(): Float = this.toInt().toFloat()
+    @kotlin.internal.InlineOnly
+    public inline fun toDouble(): Double = this.toInt().toDouble()
+
     public override fun toString(): String = toInt().toString()
 
 }
@@ -196,3 +201,12 @@ public inline fun Int.toUByte(): UByte = UByte(this.toByte())
 @ExperimentalUnsignedTypes
 @kotlin.internal.InlineOnly
 public inline fun Long.toUByte(): UByte = UByte(this.toByte())
+
+@SinceKotlin("1.3")
+@ExperimentalUnsignedTypes
+@kotlin.internal.InlineOnly
+public inline fun Float.toUByte(): UByte = doubleToUByte(this.toDouble())
+@SinceKotlin("1.3")
+@ExperimentalUnsignedTypes
+@kotlin.internal.InlineOnly
+public inline fun Double.toUByte(): UByte = doubleToUByte(this)

libraries/stdlib/unsigned/src/kotlin/UInt.kt

@@ -182,6 +182,11 @@ public inline class UInt @PublishedApi internal constructor(@PublishedApi intern
     @kotlin.internal.InlineOnly
     public inline fun toULong(): ULong = ULong(data.toLong() and 0xFFFF_FFFF)
 
+    @kotlin.internal.InlineOnly
+    public inline fun toFloat(): Float = this.toDouble().toFloat()
+    @kotlin.internal.InlineOnly
+    public inline fun toDouble(): Double = uintToDouble(data)
+
     public override fun toString(): String = toLong().toString()
 
 }
@@ -202,3 +207,12 @@ public inline fun Int.toUInt(): UInt = UInt(this)
 @ExperimentalUnsignedTypes
 @kotlin.internal.InlineOnly
 public inline fun Long.toUInt(): UInt = UInt(this.toInt())
+
+@SinceKotlin("1.3")
+@ExperimentalUnsignedTypes
+@kotlin.internal.InlineOnly
+public inline fun Float.toUInt(): UInt = doubleToUInt(this.toDouble())
+@SinceKotlin("1.3")
+@ExperimentalUnsignedTypes
+@kotlin.internal.InlineOnly
+public inline fun Double.toUInt(): UInt = doubleToUInt(this)

libraries/stdlib/unsigned/src/kotlin/ULong.kt

@@ -182,6 +182,11 @@ public inline class ULong @PublishedApi internal constructor(@PublishedApi inter
     @kotlin.internal.InlineOnly
     public inline fun toULong(): ULong = this
 
+    @kotlin.internal.InlineOnly
+    public inline fun toFloat(): Float = this.toDouble().toFloat()
+    @kotlin.internal.InlineOnly
+    public inline fun toDouble(): Double = ulongToDouble(data)
+
     public override fun toString(): String = ulongToString(data)
 
 }
@@ -202,3 +207,12 @@ public inline fun Int.toULong(): ULong = ULong(this.toLong())
 @ExperimentalUnsignedTypes
 @kotlin.internal.InlineOnly
 public inline fun Long.toULong(): ULong = ULong(this)
+
+@SinceKotlin("1.3")
+@ExperimentalUnsignedTypes
+@kotlin.internal.InlineOnly
+public inline fun Float.toULong(): ULong = doubleToULong(this.toDouble())
+@SinceKotlin("1.3")
+@ExperimentalUnsignedTypes
+@kotlin.internal.InlineOnly
+public inline fun Double.toULong(): ULong = doubleToULong(this)

libraries/stdlib/unsigned/src/kotlin/UShort.kt

@@ -176,6 +176,11 @@ public inline class UShort @PublishedApi internal constructor(@PublishedApi inte
     @kotlin.internal.InlineOnly
     public inline fun toULong(): ULong = ULong(data.toLong() and 0xFFFF)
 
+    @kotlin.internal.InlineOnly
+    public inline fun toFloat(): Float = this.toInt().toFloat()
+    @kotlin.internal.InlineOnly
+    public inline fun toDouble(): Double = this.toInt().toDouble()
+
     public override fun toString(): String = toInt().toString()
 
 }
@@ -196,3 +201,12 @@ public inline fun Int.toUShort(): UShort = UShort(this.toShort())
 @ExperimentalUnsignedTypes
 @kotlin.internal.InlineOnly
 public inline fun Long.toUShort(): UShort = UShort(this.toShort())
+
+@SinceKotlin("1.3")
+@ExperimentalUnsignedTypes
+@kotlin.internal.InlineOnly
+public inline fun Float.toUShort(): UShort = doubleToUShort(this.toDouble())
+@SinceKotlin("1.3")
+@ExperimentalUnsignedTypes
+@kotlin.internal.InlineOnly
+public inline fun Double.toUShort(): UShort = doubleToUShort(this)

libraries/stdlib/unsigned/src/kotlin/UnsignedUtils.kt

@@ -63,6 +63,50 @@ internal fun ulongRemainder(v1: ULong, v2: ULong): ULong {
 }
 
 
+@PublishedApi
+internal fun doubleToUByte(v: Double): UByte = when {
+    v.isNaN() -> 0u
+    v <= UByte.MIN_VALUE.toDouble() -> UByte.MIN_VALUE
+    v >= UByte.MAX_VALUE.toDouble() -> UByte.MAX_VALUE
+    else -> v.toInt().toUByte()
+}
+
+@PublishedApi
+internal fun doubleToUShort(v: Double): UShort = when {
+    v.isNaN() -> 0u
+    v <= UShort.MIN_VALUE.toDouble() -> UShort.MIN_VALUE
+    v >= UShort.MAX_VALUE.toDouble() -> UShort.MAX_VALUE
+    else -> v.toInt().toUShort()
+}
+
+@PublishedApi
+internal fun doubleToUInt(v: Double): UInt = when {
+    v.isNaN() -> 0u
+    v <= UInt.MIN_VALUE.toDouble() -> UInt.MIN_VALUE
+    v >= UInt.MAX_VALUE.toDouble() -> UInt.MAX_VALUE
+    v <= Int.MAX_VALUE -> v.toInt().toUInt()
+    else -> (v - Int.MAX_VALUE).toInt().toUInt() + Int.MAX_VALUE.toUInt()      // Int.MAX_VALUE < v < UInt.MAX_VALUE
+}
+
+@PublishedApi
+internal fun doubleToULong(v: Double): ULong = when {
+    v.isNaN() -> 0u
+    v <= ULong.MIN_VALUE.toDouble() -> ULong.MIN_VALUE
+    v >= ULong.MAX_VALUE.toDouble() -> ULong.MAX_VALUE
+    v < Long.MAX_VALUE -> v.toLong().toULong()
+
+    // Real values from Long.MAX_VALUE to (Long.MAX_VALUE + 1) are not representable in Double, so don't handle them.
+    else -> (v - 9223372036854775808.0).toLong().toULong() + 9223372036854775808uL      // Long.MAX_VALUE + 1 < v < ULong.MAX_VALUE
+}
+
+
+@PublishedApi
+internal fun uintToDouble(v: Int): Double = (v and Int.MAX_VALUE).toDouble() + (v ushr 31 shl 30).toDouble() * 2
+
+@PublishedApi
+internal fun ulongToDouble(v: Long): Double = (v ushr 11).toDouble() * 2048 + (v and 2047)
+
+
 internal fun ulongToString(v: Long): String = ulongToString(v, 10)
 
 internal fun ulongToString(v: Long, base: Int): String {