1827534 - Reduce nssckbi size a little more

Status: RESOLVED FIXED

(Core :: Security: PSM, task)

Description

[Mike Hommey [:glandium]]

The changes in bug 1794045 prevented me to build with rustc 1.63 downstream (I know, I know...), so I took a quick look at what it was doing and it turns out we can reduce the size of libnssckbi even more than what bug 1794045 did at the expense of a little runtime computation. On my build, by PoC saves 23KB (that's on top of the 20KB saved by bug 1794045)

Comment 1

[Mike Hommey [:glandium]]

(In reply to Mike Hommey [:glandium] from comment #0)

On my build, by PoC saves 23KB (that's on top of the 20KB saved by bug 1794045)

Make that 24.6KB (I saved a little more).

Comment 2

[Mike Hommey [:glandium]]

Attachment: Bug 1827534 - Reduce nssckbi size a little more.

This change does the following:

• Replace slices for serial and subject with offsets. This trades space
  for a pointer, a length and a relocation (which on 64-bits Linux is an
  extra 24 bytes), with runtime computation based on two offsets, that
  are small enough that they fit in 8-bits integers (and the rust
  compiler will not ignore overflows for the literals that come from
  build.rs so even if newer values overflow, that won't go unnoticed).
• "Inline" sha1 and md5 in Root as fixed-sized arrays instead of slices.
  That removes an indirection and saves the size of a fat pointer + the
  corresponding relocations.
• Make BUILTINS an array rather than a slice, which also saves a
  relocation.

Overall this saves 24.6KB on my local Linux x64 build.

Comment 3

[Mike Hommey [:glandium]]

Attachment: Bug 1827534 - Avoid builtins-static's build script errors showing more than a compile error.

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/862f76333f30
Avoid builtins-static's build script errors showing more than a compile error. r=jschanck
https://hg.mozilla.org/integration/autoland/rev/bf6d5a53da95
Reduce nssckbi size a little more. r=jschanck

Comment 5

[Narcis Beleuzu [:NarcisB]]

https://hg.mozilla.org/mozilla-central/rev/862f76333f30
https://hg.mozilla.org/mozilla-central/rev/bf6d5a53da95