Issue 10900024: Fix bug in flow graph builder that caused invalid optimization.

Keyboard Shortcuts

	File
u :	up to issue
j / k :	jump to file after / before current file
J / K :	jump to next file with a comment after / before current file
	Side-by-side diff
i :	toggle intra-line diffs
e :	expand all comments
c :	collapse all comments
s :	toggle showing all comments
n / p :	next / previous diff chunk or comment
N / P :	next / previous comment
<Up> / <Down> :	next / previous line

	Issue
u :	up to list of issues
j / k :	jump to patch after / before current patch
o / <Enter> :	open current patch in side-by-side view
i :	open current patch in unified diff view

	Issue List
j / k :	jump to issue after / before current issue
o / <Enter> :	open current issue

Issue 10900024: Fix bug in flow graph builder that caused invalid optimization. (Closed)

Created:
8 years, 3 months ago by Florian Schneider

Modified:
8 years, 3 months ago

Reviewers:
Vyacheslav Egorov (Google), srdjan

CC:
reviews_dartlang.org, vm-dev_dartlang.org, regis

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

Visibility:
Public.

More Reviews

Description

Fix bug in flow graph builder that caused invalid optimization. Using type-feedback in the flow graph builder to generate optimized code violates the invariant that the initial flow graph of the non-optimized version and the optimized version of a function have to be identical. Eliminating type checks based on type feedback has to be done later. (e.g. after the flow graph optimizer and after type propagation where we specialized operation based on type feedback) BUG=dart:4797 Committed: https://code.google.com/p/dart/source/detail?r=11515

Patch Set 1 #

Created: 8 years, 3 months ago

Download [raw] [tar.bz2]

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

Messages

Total messages: 3 (0 generated)

Expand Messages | Collapse Messages

srdjan

8 years, 3 months ago (2012-08-29 15:19:14 UTC) #3

The problem is that we eliminate type checks too eagerly, i.e. during flow graph
building. I believe this happens only for type checks of checked mode (CC-ing
Regis). All usage of cids (ResultCids) occurs in optimization pass, AFAIK. I.e.,
the change to ResultCid is probably not necessary, but is needed for
ComputeTypes until the type elimination has been moved to a later stage.

Expand Messages | Collapse Messages