While it is already mentioned on the `items` attributes of the structs, it is
interesting to comment in every method potentially invalidating pointers to items
that they may do so.
* std.crypto.onetimeauth.ghash: faster GHASH on modern CPUs
Carryless multiplication was slow on older Intel CPUs, justifying
the need for using Karatsuba multiplication.
This is not the case any more; using 4 multiplications to multiply
two 128-bit numbers is actually faster than 3 multiplications +
shifts and additions.
This is also true on aarch64.
Keep using Karatsuba only when targeting x86 (granted, this is a bit
of a brutal shortcut, we should really list all the CPU models that
had a slow clmul instruction).
Also remove useless agg_2 treshold and restore the ability to
precompute only H and H^2 in ReleaseSmall.
Finally, avoid using u256. Using 128-bit registers is actually faster.
* Use a switch, add some comments
The packed struct example was mistakenly applying endianness where it
shouldn't have been. This wasn't being caught because we don't currently
test the examples on Big-endian systems.
I updated the test to remove the endianness where it didn't apply, and
added a new part of the test to demonstrate when it would apply.
perf_event_attr.type needs to take a runtime defined value to enable
dynamic PMU:s, such as kprobe and uprobe. This value can exceed
predefined values defined in the linux headers.
reference: perf_event_open(2) man page
Previously the compiler would crash on branching on undefined values
if you tried using `zig test` with a freestanding target since there
was no start code referencing `builtin.test_functions`.
Closes#12554
* point to init part of field delc when that's where the error occurs
* update test to reflect fixed error message
* only lookup source location in case of error
In the process of 'remaining blocks',
the length of processed message can be from 1 to 79.
The value of 'n-1' is ranged from 0 to 3.
So, st.hx[i] must be initialized at least from st.hx[0] to st.hx[3]
These parameters are only ever needed when `std.builtin` is out of sync
with the compiler in which case panicking is the only valid operation
anyways. Removing them causes a domino effect of functions no longer
needing a `src` and/or a `block` parameter resulting in handling
compilation errors where they are actually meaningful becoming simpler.
