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package runtime
import "core:intrinsics"
@(link_name="__umodti3")
umodti3 :: proc "c" (a, b: u128) -> u128 {
r: u128 = ---
_ = udivmod128(a, b, &r)
return r
}
@(link_name="__udivmodti4")
udivmodti4 :: proc "c" (a, b: u128, rem: ^u128) -> u128 {
return udivmod128(a, b, rem)
}
@(link_name="__udivti3")
udivti3 :: proc "c" (a, b: u128) -> u128 {
return udivmodti4(a, b, nil)
}
@(link_name="__modti3")
modti3 :: proc "c" (a, b: i128) -> i128 {
s_a := a >> (128 - 1)
s_b := b >> (128 - 1)
an := (a ~ s_a) - s_a
bn := (b ~ s_b) - s_b
r: u128 = ---
_ = udivmod128(transmute(u128)an, transmute(u128)bn, &r)
return (transmute(i128)r ~ s_a) - s_a
}
@(link_name="__divmodti4")
divmodti4 :: proc "c" (a, b: i128, rem: ^i128) -> i128 {
u := udivmod128(transmute(u128)a, transmute(u128)b, cast(^u128)rem)
return transmute(i128)u
}
@(link_name="__divti3")
divti3 :: proc "c" (a, b: i128) -> i128 {
u := udivmodti4(transmute(u128)a, transmute(u128)b, nil)
return transmute(i128)u
}
@(link_name="__fixdfti")
fixdfti :: proc(a: u64) -> i128 {
significandBits :: 52
typeWidth :: (size_of(u64)*8)
exponentBits :: (typeWidth - significandBits - 1)
maxExponent :: ((1 << exponentBits) - 1)
exponentBias :: (maxExponent >> 1)
implicitBit :: (u64(1) << significandBits)
significandMask :: (implicitBit - 1)
signBit :: (u64(1) << (significandBits + exponentBits))
absMask :: (signBit - 1)
exponentMask :: (absMask ~ significandMask)
// Break a into sign, exponent, significand
aRep := a
aAbs := aRep & absMask
sign := i128(-1 if aRep & signBit != 0 else 1)
exponent := u64((aAbs >> significandBits) - exponentBias)
significand := u64((aAbs & significandMask) | implicitBit)
// If exponent is negative, the result is zero.
if exponent < 0 {
return 0
}
// If the value is too large for the integer type, saturate.
if exponent >= size_of(i128) * 8 {
return max(i128) if sign == 1 else min(i128)
}
// If 0 <= exponent < significandBits, right shift to get the result.
// Otherwise, shift left.
if exponent < significandBits {
return sign * i128(significand >> (significandBits - exponent))
} else {
return sign * (i128(significand) << (exponent - significandBits))
}
}
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