Issue 4298: Use -O9, tune for nocoma, assume at least a Pentium when generating code.

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Issue 4298: Use -O9, tune for nocoma, assume at least a Pentium when generating code. (Closed)

Created:
12 years, 2 months ago by Erik Corry

Modified:
9 years, 7 months ago

Reviewers:
bak, DannyB

CC:
v8-dev

Base URL:
http://v8.googlecode.com/svn/branches/bleeding_edge/

Visibility:
Public.

Description

Use -O9, tune for nocoma, assume at least a Pentium when generating code. Committed: http://code.google.com/p/v8/source/detail?r=387

Patch Set 1 #

Created: 12 years, 2 months ago

Download [raw] [tar.bz2]

		Unified diffs	Side-by-side diffs	Delta from patch set	Stats (+6 lines, -6 lines)			Patch
	M	SConstruct	View		3 chunks	+3 lines, -3 lines	0 comments	Download
	M	src/objects.cc	View		3 chunks	+3 lines, -3 lines	2 comments	Download

Messages

Total messages: 3 (0 generated)

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bak

Let's try it out. Please revert you changes if this does not yield a measurable ...

12 years, 2 months ago (2008-09-26 12:21:59 UTC) #2

DannyB

12 years, 2 months ago (2008-09-26 21:09:55 UTC) #3

Please *don't* use O9.
(I'm a gcc dev)


GCC's highest supported level of optimization is O3.
We only make it not error out to avoid gentoo users whining. It does nothing.

There is also good chance in the future that O4 or O5 may start doing link time
optimization (which would require a different link command to work properly) or
possibly break standards conforming code in order to get better performance
(integer overflow guarantees, etc).

Using O9 just means you are going to cause yourself pain, but it will not help
anything.

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