The first biggest offender was crypto/des.init at ~1%. It's
cryptographically broken and the init function is relatively expensive,
which is unfortunate as both crypto/tls and crypto/x509 (and by
extension, cmd/go) import it. Hide the work behind sync.Once.
The second biggest offender was flag.sortFlags at just under 1%, used by
the Visit flagset methods. It allocated two slices, which made a
difference as cmd/go iterates over multiple flagsets during init.
Use a single slice with a direct sort.Interface implementation.
Another big offender is initializing global maps. Reducing this work in
cmd/go/internal/imports and net/textproto gives us close to another
whole 1% in saved work. The former can use map literals, and the latter
can hide the work behind sync.Once.
Finally, compress/flate used newHuffmanBitWriter as part of init, which
allocates many objects and slices. Yet it only used one of the slice
fields. Allocating just that slice saves a surprising ~0.3%, since we
generated a lot of unnecessary garbage.
All in all, these little pieces amount to just over 3% saved CPU time.
name old time/op new time/op delta
ExecGoEnv-8 3.61ms ± 1% 3.50ms ± 0% -3.02% (p=0.000 n=10+10)
Updates #26775.
Updates #29382.
Change-Id: I915416e88a874c63235ba512617c8aef35c0ca8b
Reviewed-on: https://go-review.googlesource.com/c/go/+/166459
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Normalized all panic checks and added inexact aliasing panics across
Stream, Block, BlockMode and AEAD implementations.
Also, tweaked the aliasing docs of cipher.AEAD, as they did not account
for the append nature of the API.
Fixes#21624
Change-Id: I075c4415f59b3c06e3099bd9f76de6d12af086bf
Reviewed-on: https://go-review.googlesource.com/109697
Run-TryBot: Filippo Valsorda <filippo@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This change explicitly documents that DES, MD5, RC4 and SHA-1 are
insecure / broken - at all or at least within a commonly used scenario.
Fixes#14395
Change-Id: Id1d543c85d67968ba64ed7495313501953c3ef3a
Reviewed-on: https://go-review.googlesource.com/42511
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
cmd and runtime were handled separately, and I'm intentionally skipped
syscall. This is the rest of the standard library.
CL generated mechanically with github.com/mdempsky/unconvert.
Change-Id: I9e0eff886974dedc37adb93f602064b83e469122
Reviewed-on: https://go-review.googlesource.com/22104
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>