1532974 - wasm baseline compiler: increase some Vector inline-capacity sizes

Status: RESOLVED FIXED

(Core :: JavaScript: WebAssembly, enhancement)

Description

[Julian Seward [:jseward]]

Profiling with DHAT of wasm baseline compiling the Tanks demo shows some
opportunities for reducing the amount of heap allocation, by modestly
increasing the inline-capacity values for a few Vector types.

Comment 1

[Julian Seward [:jseward]]

Attachment: bug1532974-vec-adjust-1.diff

With the patch from bug 1532592 applied before this one, for compiling the
Tanks demo on an x86_64-linux build, gcc 8.2.1, -O2, this patch reduces the
amount of heap allocation from 156,924,761 bytes in 60,767 blocks to
155,993,057 bytes in 48,713 blocks. The instruction count falls from 2379
million to 2377 million.

Taking together this patch and the patch from bug 1532592, the number of heap
blocks is reduced to 51.5% of what it was, and total allocation to 69.0% of
what it was. Instruction count is down 0.7%.

Comment 2

[Julian Seward [:jseward]]

Attachment: bug1532974-vec-adjust-2.diff

Comment 3

[Julian Seward [:jseward]]

Attachment: Bug 1532974 - wasm baseline compiler: increase some Vector inline-capacity sizes.

Profiling with DHAT of wasm baseline compiling the Tanks demo shows some
opportunities for reducing the amount of heap allocation, by modestly
increasing the inline-capacity values for a few Vector types.

Compiling the Tanks demo on x86_64-linux, this patch reduces the number of
allocated blocks by around 12000, whilst increasing neither the total
allocated bytes nor the dynamic instruction count.

Comment 4

[BugBot [:suhaib / :marco/ :calixte]]

There are some r+ patches which didn't land and no activity in this bug for 2 weeks.
:jseward, could you have a look please?

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/d3af807647a0
wasm baseline compiler: increase some Vector inline-capacity sizes.  r=lhansen.

Comment 6

[Stefan Hindli [:stefan_hindli]]

https://hg.mozilla.org/mozilla-central/rev/d3af807647a0