DoxigAlpha

setTwosCompIntLimit

Set self to either bound of a 2s-complement integer. Note: The result is still sign-magnitude, not twos complement! In order to convert the result to twos complement, it is sufficient to take the absolute value.

Function parameters

Parameters

#
r:*Managed
bit_count:usize

Used to indicate either limit of a 2s-complement integer.

Types

#
TwosCompIntLimit
Used to indicate either limit of a 2s-complement integer.
Mutable
A arbitrary-precision big integer, with a fixed set of mutable limbs.
Const
A arbitrary-precision big integer, with a fixed set of immutable limbs.
Managed
An arbitrary-precision big integer along with an allocator which manages the memory.

Returns the number of limbs needed to store `scalar`, which must be a

Functions

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calcLimbLen
Returns the number of limbs needed to store `scalar`, which must be a
calcSetStringLimbCount
Assumes `string_len` doesn't account for minus signs if the number is negative.
calcNonZeroTwosCompLimbCount
Compute the number of limbs required to store a 2s-complement number of `bit_count` bits.
calcTwosCompLimbCount
Compute the number of limbs required to store a 2s-complement number of `bit_count` bits.
addMulLimbWithCarry
a + b * c + *carry, sets carry to the overflow bits
llcmp
Returns -1, 0, 1 if |a| < |b|, |a| == |b| or |a| > |b| respectively for limbs.

Source

Implementation

#
pub fn setTwosCompIntLimit(
    r: *Managed,
    limit: TwosCompIntLimit,
    signedness: Signedness,
    bit_count: usize,
) !void {
    try r.ensureCapacity(calcTwosCompLimbCount(bit_count));
    var m = r.toMutable();
    m.setTwosCompIntLimit(limit, signedness, bit_count);
    r.setMetadata(m.positive, m.len);
}