(* abc9_box, lib_whitebox *)
module \$__ICE40_CARRY_WRAPPER (
(* abc9_carry *)
output CO,
output O,
input A, B,
(* abc9_carry *)
input CI,
input I0, I3
);
parameter LUT = 0;
parameter I3_IS_CI = 0;
wire I3_OR_CI = I3_IS_CI ? CI : I3;
SB_CARRY carry (
.I0(A),
.I1(B),
.CI(CI),
.CO(CO)
);
SB_LUT4 #(
.LUT_INIT(LUT)
) adder (
.I0(I0),
.I1(A),
.I2(B),
.I3(I3_OR_CI),
.O(O)
);
`ifdef ICE40_HX
specify
// https://github.com/cliffordwolf/icestorm/blob/be0bca0230d6fe1102e0a360b953fbb0d273a39f/icefuzz/timings_hx1k.txt#L79
(CI => CO) = (126, 105);
// https://github.com/cliffordwolf/icestorm/blob/be0bca0230d6fe1102e0a360b953fbb0d273a39f/icefuzz/timings_hx1k.txt#L80
(I0 => O) = (449, 386);
// https://github.com/cliffordwolf/icestorm/blob/be0bca0230d6fe1102e0a360b953fbb0d273a39f/icefuzz/timings_hx1k.txt#L82
(A => CO) = (259, 245);
// https://github.com/cliffordwolf/icestorm/blob/be0bca0230d6fe1102e0a360b953fbb0d273a39f/icefuzz/timings_hx1k.txt#L83
(A => O) = (400, 379);
// https://github.com/cliffordwolf/icestorm/blob/be0bca0230d6fe1102e0a360b953fbb0d273a39f/icefuzz/timings_hx1k.txt#L85
(B => CO) = (231, 133);
// https://github.com/cliffordwolf/icestorm/blob/be0bca0230d6fe1102e0a360b953fbb0d273a39f/icefuzz/timings_hx1k.txt#L86
(B => O) = (379, 351);
// https://github.com/cliffordwolf/icestorm/blob/be0bca0230d6fe1102e0a360b953fbb0d273a39f/icefuzz/timings_hx1k.txt#L88
(I3 => O) = (316, 288);
(CI => O) = (316, 288);
endspecify
`endif
`ifdef ICE40_LP
specify
// https://github.com/cliffordwolf/icestorm/blob/be0bca0230d6fe1102e0a360b953fbb0d273a39f/icefuzz/timings_lp1k.txt#L79
(CI => CO) = (186, 155);
// https://github.com/cliffordwolf/icestorm/blob/be0bca0230d6fe1102e0a360b953fbb0d273a39f/icefuzz/timings_lp1k.txt#L80
(I0 => O) = (662, 569);
// https://github.com/cliffordwolf/icestorm/blob/be0bca0230d6fe1102e0a360b953fbb0d273a39f/icefuzz/timings_lp1k.txt#L82
(A => CO) = (382, 362);
// https://github.com/cliffordwolf/icestorm/blob/be0bca0230d6fe1102e0a360b953fbb0d273a39f/icefuzz/timings_lp1k.txt#L83
(A => O) = (589, 558);
// https://github.com/cliffordwolf/icestorm/blob/be0bca0230d6fe1102e0a360b953fbb0d273a39f/icefuzz/timings_lp1k.txt#L85
(B => CO) = (341, 196);
// https://github.com/cliffordwolf/icestorm/blob/be0bca0230d6fe1102e0a360b953fbb0d273a39f/icefuzz/timings_lp1k.txt#L86
(B => O) = (558, 517);
// https://github.com/cliffordwolf/icestorm/blob/be0bca0230d6fe1102e0a360b953fbb0d273a39f/icefuzz/timings_lp1k.txt#L88
(I3 => O) = (465, 423);
(CI => O) = (465, 423);
endspecify
`endif
`ifdef ICE40_U
specify
// https://github.com/cliffordwolf/icestorm/blob/be0bca0230d6fe1102e0a360b953fbb0d273a39f/icefuzz/timings_up5k.txt#L91
(CI => CO) = (278, 278);
// https://github.com/cliffordwolf/icestorm/blob/be0bca0230d6fe1102e0a360b953fbb0d273a39f/icefuzz/timings_up5k.txt#L92
(I0 => O) = (1245, 1285);
// https://github.com/cliffordwolf/icestorm/blob/be0bca0230d6fe1102e0a360b953fbb0d273a39f/icefuzz/timings_up5k.txt#L94
(A => CO) = (675, 662);
// https://github.com/cliffordwolf/icestorm/blob/be0bca0230d6fe1102e0a360b953fbb0d273a39f/icefuzz/timings_up5k.txt#L95
(A => O) = (1179, 1232);
// https://github.com/cliffordwolf/icestorm/blob/be0bca0230d6fe1102e0a360b953fbb0d273a39f/icefuzz/timings_up5k.txt#L97
(B => CO) = (609, 358);
// https://github.com/cliffordwolf/icestorm/blob/be0bca0230d6fe1102e0a360b953fbb0d273a39f/icefuzz/timings_up5k.txt#L98
(B => O) = (1179, 1205);
// https://github.com/cliffordwolf/icestorm/blob/be0bca0230d6fe1102e0a360b953fbb0d273a39f/icefuzz/timings_up5k.txt#L100
(I3 => O) = (861, 874);
(CI => O) = (861, 874);
endspecify
`endif
endmodule
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API stability
=============
From its first release, ``cryptography`` will have a strong API stability
policy.
What does this policy cover?
----------------------------
This policy includes any API or behavior that is documented in this
documentation.
What does "stable" mean?
------------------------
* Public APIs will not be removed or renamed without providing a compatibility
alias.
* The behavior of existing APIs will not change.
What doesn't this policy cover?
-------------------------------
* We may add new features, things like the result of ``dir(obj))`` or the
contents of ``obj.__dict__`` may change.
* Objects are not guaranteed to be pickleable, and pickled objects from one
version of ``cryptography`` may not be loadable in future versions.
* Development versions of ``cryptography``. Before a feature is in a release,
it is not covered by this policy and may change.
Security
~~~~~~~~
One exception to our API stability policy is for security. We will violate this
policy as necessary in order to resolve a security issue or harden
``cryptography`` against a possible attack.
Deprecation
-----------
From time to time we will want to change the behavior of an API or remove it
entirely. In that case, here's how the process will work:
* In ``cryptography X.Y`` the feature exists.
* In ``cryptography X.Y+1`` using that feature will emit a
``PendingDeprecationWarning``.
* In ``cryptography X.Y+2`` using that feature will emit a
``DeprecationWarning``.
* In ``cryptography X.Y+3`` the feature will be removed or changed.
In short, code that runs without warnings will always continue to work for a
period of two releases.
|