discard """
output: "OK"
"""
import macros
type
Dollar = distinct int
XCoord = distinct int32
Digit = range[-9..0]
# those are necessary for comparisons below.
proc `==`(x, y: Dollar): bool {.borrow.}
proc `==`(x, y: XCoord): bool {.borrow.}
proc dummy[T](x: T): T = x
proc test() =
let U8 = 0b1011_0010'u8
let I8 = 0b1011_0010'i8
let C8 = 0b1011_0010'u8.char
let C8_1 = 0b1011_0011'u8.char
let U16 = 0b10100111_00101000'u16
let I16 = 0b10100111_00101000'i16
let U32 = 0b11010101_10011100_11011010_01010000'u32
let I32 = 0b11010101_10011100_11011010_01010000'i32
let U64A = 0b11000100_00111111_01111100_10001010_10011001_01001000_01111010_00010001'u64
let I64A = 0b11000100_00111111_01111100_10001010_10011001_01001000_01111010_00010001'i64
let U64B = 0b00110010_11011101_10001111_00101000_00000000_00000000_00000000_00000000'u64
let I64B = 0b00110010_11011101_10001111_00101000_00000000_00000000_00000000_00000000'i64
when sizeof(int) == 8:
let UX = U64A.uint
let IX = I64A.int
elif sizeof(int) == 4:
let UX = U32.uint
let IX = I32.int
elif sizeof(int) == 2:
let UX = U16.uint
let IX = I16.int
else:
let UX = U8.uint
let IX = I8.int
doAssert(cast[char](I8) == C8)
doAssert(cast[uint8](I8) == U8)
doAssert(cast[uint16](I16) == U16)
doAssert(cast[uint32](I32) == U32)
doAssert(cast[uint64](I64A) == U64A)
doAssert(cast[uint64](I64B) == U64B)
doAssert(cast[int8](U8) == I8)
doAssert(cast[int16](U16) == I16)
doAssert(cast[int32](U32) == I32)
doAssert(cast[int64](U64A) == I64A)
doAssert(cast[int64](U64B) == I64B)
doAssert(cast[uint](IX) == UX)
doAssert(cast[int](UX) == IX)
doAssert(cast[char](I8 + 1) == C8_1)
doAssert(cast[uint8](I8 + 1) == U8 + 1)
doAssert(cast[uint16](I16 + 1) == U16 + 1)
doAssert(cast[uint32](I32 + 1) == U32 + 1)
doAssert(cast[uint64](I64A + 1) == U64A + 1)
doAssert(cast[uint64](I64B + 1) == U64B + 1)
doAssert(cast[int8](U8 + 1) == I8 + 1)
doAssert(cast[int16](U16 + 1) == I16 + 1)
doAssert(cast[int32](U32 + 1) == I32 + 1)
doAssert(cast[int64](U64A + 1) == I64A + 1)
doAssert(cast[int64](U64B + 1) == I64B + 1)
doAssert(cast[uint](IX + 1) == UX + 1)
doAssert(cast[int](UX + 1) == IX + 1)
doAssert(cast[char](I8.dummy) == C8.dummy)
doAssert(cast[uint8](I8.dummy) == U8.dummy)
doAssert(cast[uint16](I16.dummy) == U16.dummy)
doAssert(cast[uint32](I32.dummy) == U32.dummy)
doAssert(cast[uint64](I64A.dummy) == U64A.dummy)
doAssert(cast[uint64](I64B.dummy) == U64B.dummy)
doAssert(cast[int8](U8.dummy) == I8.dummy)
doAssert(cast[int16](U16.dummy) == I16.dummy)
doAssert(cast[int32](U32.dummy) == I32.dummy)
doAssert(cast[int64](U64A.dummy) == I64A.dummy)
doAssert(cast[int64](U64B.dummy) == I64B.dummy)
doAssert(cast[uint](IX.dummy) == UX.dummy)
doAssert(cast[int](UX.dummy) == IX.dummy)
doAssert(cast[int64](if false: U64B else: 0'u64) == (if false: I64B else: 0'i64))
block:
let raw = 3
let money = Dollar(raw) # this must be a variable, is otherwise constant folded.
doAssert(cast[int](money) == raw)
doAssert(cast[Dollar](raw) == money)
block:
let raw = 150'i32
let position = XCoord(raw) # this must be a variable, is otherwise constant folded.
doAssert(cast[int32](position) == raw)
doAssert(cast[XCoord](raw) == position)
block:
let raw = -2
let digit = Digit(raw)
doAssert(cast[int](digit) == raw)
doAssert(cast[Digit](raw) == digit)
when defined nimvm:
doAssert(not compiles(cast[float](I64A)))
doAssert(not compiles(cast[float32](I64A)))
doAssert(not compiles(cast[char](I64A)))
doAssert(not compiles(cast[uint16](I64A)))
doAssert(not compiles(cast[uint32](I64A)))
doAssert(not compiles(cast[uint16](I8)))
doAssert(not compiles(cast[uint32](I8)))
doAssert(not compiles(cast[uint64](I8)))
const prerecordedResults = [
# cast to char
"\0", "\255",
"\0", "\255",
"\0", "\255",
"\0", "\255",
"\0", "\255",
"\128", "\127",
"\0", "\255",
"\0", "\255",
"\0", "\255",
# cast to uint8
"0", "255",
"0", "255",
"0", "255",
"0", "255",
"0", "255",
"128", "127",
"0", "255",
"0", "255",
"0", "255",
# cast to uint16
"0", "255",
"0", "255",
"0", "65535",
"0", "65535",
"0", "65535",
"65408", "127",
"32768", "32767",
"0", "65535",
"0", "65535",
# cast to uint32
"0", "255",
"0", "255",
"0", "65535",
"0", "4294967295",
"0", "4294967295",
"4294967168", "127",
"4294934528", "32767",
"2147483648", "2147483647",
"0", "4294967295",
# cast to uint64
"0", "255",
"0", "255",
"0", "65535",
"0", "4294967295",
"0", "18446744073709551615",
"18446744073709551488", "127",
"18446744073709518848", "32767",
"18446744071562067968", "2147483647",
"9223372036854775808", "9223372036854775807",
# cast to int8
"0", "-1",
"0", "-1",
"0", "-1",
"0", "-1",
"0", "-1",
"-128", "127",
"0", "-1",
"0", "-1",
"0", "-1",
# cast to int16
"0", "255",
"0", "255",
"0", "-1",
"0", "-1",
"0", "-1",
"-128", "127",
"-32768", "32767",
"0", "-1",
"0", "-1",
# cast to int32
"0", "255",
"0", "255",
"0", "65535",
"0", "-1",
"0", "-1",
"-128", "127",
"-32768", "32767",
"-2147483648", "2147483647",
"0", "-1",
# cast to int64
"0", "255",
"0", "255",
"0", "65535",
"0", "4294967295",
"0", "-1",
"-128", "127",
"-32768", "32767",
"-2147483648", "2147483647",
"-9223372036854775808", "9223372036854775807",
]
proc free_integer_casting() =
# cast from every integer type to every type and ensure same
# behavior in vm and execution time.
macro bar(arg: untyped) =
result = newStmtList()
var i = 0
for it1 in arg:
let typA = it1[0]
for it2 in arg:
let lowB = it2[1]
let highB = it2[2]
let castExpr1 = nnkCast.newTree(typA, lowB)
let castExpr2 = nnkCast.newTree(typA, highB)
let lit1 = newLit(prerecordedResults[i*2])
let lit2 = newLit(prerecordedResults[i*2+1])
result.add quote do:
doAssert($(`castExpr1`) == `lit1`)
doAssert($(`castExpr2`) == `lit2`)
i += 1
bar([
(char, '\0', '\255'),
(uint8, 0'u8, 0xff'u8),
(uint16, 0'u16, 0xffff'u16),
(uint32, 0'u32, 0xffffffff'u32),
(uint64, 0'u64, 0xffffffffffffffff'u64),
(int8, 0x80'i8, 0x7f'i8),
(int16, 0x8000'i16, 0x7fff'i16),
(int32, 0x80000000'i32, 0x7fffffff'i32),
(int64, 0x8000000000000000'i64, 0x7fffffffffffffff'i64)
])
proc test_float_cast =
const
exp_bias = 1023'i64
exp_shift = 52
exp_mask = 0x7ff'i64 shl exp_shift
mantissa_mask = 0xfffffffffffff'i64
let f = 8.0
let fx = cast[int64](f)
let exponent = ((fx and exp_mask) shr exp_shift) - exp_bias
let mantissa = fx and mantissa_mask
doAssert(exponent == 3, $exponent)
doAssert(mantissa == 0, $mantissa)
# construct 2^N float, where N is integer
let x = -2'i64
let xx = (x + exp_bias) shl exp_shift
let xf = cast[float](xx)
doAssert(xf == 0.25, $xf)
proc test_float32_cast =
const
exp_bias = 127'i32
exp_shift = 23
exp_mask = 0x7f800000'i32
mantissa_mask = 0x007ffff'i32
let f = -0.5'f32
let fx = cast[int32](f)
let exponent = ((fx and exp_mask) shr exp_shift) - exp_bias
let mantissa = fx and mantissa_mask
doAssert(exponent == -1, $exponent)
doAssert(mantissa == 0, $mantissa)
# construct 2^N float32 where N is integer
let x = 4'i32
let xx = (x + exp_bias) shl exp_shift
let xf = cast[float32](xx)
doAssert(xf == 16.0'f32, $xf)
proc test_float32_castB() =
let a: float32 = -123.125
let b = cast[int32](a)
let c = cast[uint32](a)
doAssert b == -1024049152
doAssert cast[uint64](b) == 18446744072685502464'u64
doAssert c == 3270918144'u32
# ensure the unused bits in the internal representation don't have
# any surprising content.
doAssert cast[uint64](c) == 3270918144'u64
test()
test_float_cast()
test_float32_cast()
free_integer_casting()
test_float32_castB()
static:
test()
test_float_cast()
test_float32_cast()
free_integer_casting()
test_float32_castB()
echo "OK"