1850951 - Avoid redundant initialisation of large buffer under -ftrivial-auto-var-init

Status: RESOLVED FIXED

(Firefox Build System :: General, task)

Description

[[:sergesanspaille]]

When a buffer is declared inside a loop and the compiler generates initialization code for it through -ftrivial-auto-var-init, the compiler can move the stack allocation outside the loop, but to the memory initialization (this would change the scope of the initialization).

This implies an extra overhead that we may not want to pay. Declaring the buffer in the outer scope of the loop is enough to initialize the buffer only once.

Comment 1

[[:sergesanspaille]]

Attachment: Bug 1850951 - Avoid redundant initialisation of large buffer under -ftrivial-auto-var-init r=emilio

Comment 2

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/cf7f0013cf6d
Avoid redundant initialisation of large buffer under -ftrivial-auto-var-init r=emilio

Comment 3

[Sandor Molnar[:smolnar]]

https://hg.mozilla.org/mozilla-central/rev/cf7f0013cf6d