Relax assumptions about control flow in the hydrogen graph.

Relax assumptions about control flow in the hydrogen graph.

Previously we assumed that control was always live after visiting an
expression, and that control was live to both basic block targets of an
expression in a test context.

Now we allow any expression to exit the graph.

R=fschneider@chromium.org,danno@chromium.org

Committed: http://code.google.com/p/v8/source/detail?r=7601

[Kevin Millikin (Chromium), 2011-04-13 10:30:52]

I also redid the macros we use to bailout and check for bailout.

[fschneider, 2011-04-13 11:20:16]

LGTM.

http://codereview.chromium.org/6839015/diff/1/src/hydrogen.cc
File src/hydrogen.cc (right):

http://codereview.chromium.org/6839015/diff/1/src/hydrogen.cc#newcode4718
src/hydrogen.cc:4718: VisitForTypeOf(expr->expression());
CHECK_ALIVE(VisitForTypeOf(expr->expression()));

http://codereview.chromium.org/6839015/diff/1/src/hydrogen.cc#newcode5133
src/hydrogen.cc:5133: VisitForTypeOf(left_unary->expression());
CHECK_ALIVE(left_unary->expression());

[Kevin Millikin (Chromium), 2011-04-13 11:22:58]

Thanks, changed it everywhere I could.

[danno, 2011-04-13 12:00:43]

LGTM

http://codereview.chromium.org/6839015/diff/1/src/hydrogen.cc
File src/hydrogen.cc (right):

http://codereview.chromium.org/6839015/diff/1/src/hydrogen.cc#newcode2277
src/hydrogen.cc:2277: if (scope->function() != NULL) return Bailout("named
function expression");
I didn't know this actually works, returning the result of a void function call.
Is this something done elsewhere in the code?

http://codereview.chromium.org/6839015/diff/1/src/hydrogen.cc#newcode2808
src/hydrogen.cc:2808: ASSERT(!HasStackOverflow());
Turn these three checks into a single check, like ASSERT(HasNotBailedOut())?

[Kevin Millikin (Chromium), 2011-04-13 12:23:24]

http://codereview.chromium.org/6839015/diff/1/src/hydrogen.cc
File src/hydrogen.cc (right):

http://codereview.chromium.org/6839015/diff/1/src/hydrogen.cc#newcode2277
src/hydrogen.cc:2277: if (scope->function() != NULL) return Bailout("named
function expression");
On 2011/04/13 12:00:43, danno wrote:
> I didn't know this actually works, returning the result of a void function
call.
> Is this something done elsewhere in the code?

I'm not sure if it's done elsewhere, I can't think of a place (except a few I
fixed because they were accidental).

Here it seems fairly "principled".  If it makes you squeamish, compare it to the
macro :-)

http://codereview.chromium.org/6839015/diff/1/src/hydrogen.cc#newcode2808
src/hydrogen.cc:2808: ASSERT(!HasStackOverflow());
On 2011/04/13 12:00:43, danno wrote:
> Turn these three checks into a single check, like ASSERT(HasNotBailedOut())?

OK, I'll do that.