932618 - Don't override C*FLAGS to disable PGO for single files

Status: RESOLVED FIXED

(Firefox Build System :: General, defect)

Description

[Mike Hommey [:glandium]]

We have a bunch of things like:
MonoIC.$(OBJ_SUFFIX): CXXFLAGS += -GL-

We should stop doing that. My proposal is to define a list of files that shouldn't be PGOed. My current attempt does that by defining that list in NO_PROFILE_GUIDED_OPTIMIZE which is already what we use to disable in a directory. So that variable takes either 1 in which case it's the whole directory, or a list of source files.

Comment 1

[Mike Hommey [:glandium]]

Attachment: Use NO_PROFILE_GUIDED_OPTIMIZE to disable PGO for individual files

I'm testing this on try.

Comment 2

[Mike Hommey [:glandium]]

Attachment: Use NO_PROFILE_GUIDED_OPTIMIZE to disable PGO for individual files

This seems to work. The next step I'm planning from here is to move NO_PROFILE_GUIDED_OPTIMIZE to moz.build, and make it a list eveywhere: in moz.build, we can do NO_PROFILE_GUIDED_OPTIMIZE = SOURCES when we don't want anything optimized in the corresponding directory.

Comment 3

[(not currently active) Ted Mielczarek]

The "list sources that don't get optimized" behavior seems useful, but the "NO_PROFILE_GUIDED_OPTIMIZE = SOURCES" bit seems kind of gross.

Comment 4

[Mike Hommey [:glandium]]

(In reply to Ted Mielczarek [:ted.mielczarek] from comment #3)
> The "list sources that don't get optimized" behavior seems useful, but the
> "NO_PROFILE_GUIDED_OPTIMIZE = SOURCES" bit seems kind of gross.

It's not more gross than having either two variables or having one variable with two possible types.

Comment 5

[Makoto Kato [:m_kato]]

MonoIC.cpp and Compiler.cpp in js/src were for JaegerMonkey.  These files were removed when removing JaegerMonkey.

Comment 6

[Gregory Szorc [:gps]]

Comment on attachment 824578 [details] [diff] [review]
Use NO_PROFILE_GUIDED_OPTIMIZE to disable PGO for individual files

Review of attachment 824578 [details] [diff] [review]:
-----------------------------------------------------------------

Lazy evaluated behavior is the worst. This is going to make converting parts of config.mk to Python pretty gnarly.

Comment 7

[Mike Hommey [:glandium]]

(In reply to Gregory Szorc [:gps] from comment #6)
> Lazy evaluated behavior is the worst. This is going to make converting parts
> of config.mk to Python pretty gnarly.

Parts related to pgo can't be converted, as they are dynamic by nature.

Comment 8

[Mike Hommey [:glandium]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/0fc3f0660258

Comment 9

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

https://hg.mozilla.org/mozilla-central/rev/0fc3f0660258