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This is an example of documentation generated by ZigDoc, an alternative to Zig's built-in Auto Doc feature. See also examples in other modes/formats. The project being documented here (as the example) is the Zig standard library. Public Function

mulWrap

Public Function
std.math.big.int.Mutable.mulWrap
pub fn mulWrap(
        rma: *Mutable,
        a: Const,
        b: Const,
        signedness: Signedness,
        bit_count: usize,
        limbs_buffer: []Limb,
        allocator: ?Allocator,
    ) void

rma = a * b with 2s-complement wrapping semantics.

rma may alias with a or b. a and b may alias with each other.

Asserts the result fits in rma. An upper bound on the number of limbs needed by rma is given by a.limbs.len + b.limbs.len.

limbs_buffer is used for temporary storage. The amount required is given by calcMulWrapLimbsBufferLen.

Params

File

math/big/int.zig:854
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    pub fn mulWrap(
        rma: *Mutable,
        a: Const,
        b: Const,
        signedness: Signedness,
        bit_count: usize,
        limbs_buffer: []Limb,
        allocator: ?Allocator,
    ) void {
        var buf_index: usize = 0;
        const req_limbs = calcTwosCompLimbCount(bit_count);

        const a_copy = if (rma.limbs.ptr == a.limbs.ptr) blk: {
            const start = buf_index;
            const a_len = @min(req_limbs, a.limbs.len);
            @memcpy(limbs_buffer[buf_index..][0..a_len], a.limbs[0..a_len]);
            buf_index += a_len;
            break :blk a.toMutable(limbs_buffer[start..buf_index]).toConst();
        } else a;

        const b_copy = if (rma.limbs.ptr == b.limbs.ptr) blk: {
            const start = buf_index;
            const b_len = @min(req_limbs, b.limbs.len);
            @memcpy(limbs_buffer[buf_index..][0..b_len], b.limbs[0..b_len]);
            buf_index += b_len;
            break :blk a.toMutable(limbs_buffer[start..buf_index]).toConst();
        } else b;

        return rma.mulWrapNoAlias(a_copy, b_copy, signedness, bit_count, allocator);
    }