Support for post-fix count operations (x++, x--) where x is a global...

Support for post-fix count operations (x++, x--) where x is a global
variable for the top-level compiler.


Committed: http://code.google.com/p/v8/source/detail?r=3194

[Kevin Millikin (Chromium), 2009-10-31 20:19:05]

LGTM.

[Kevin Millikin (Chromium), 2009-10-31 20:20:42]

http://codereview.chromium.org/342058/diff/1/3
File src/ia32/fast-codegen-ia32.cc (right):

http://codereview.chromium.org/342058/diff/1/3#newcode937
Line 937: ASSERT(v->AsVariable() != NULL && v->AsVariable() != NULL);
I'm not sure what you intended the other half of this assert to be.

If the assert is a conjunction, we usually write it as separate asserts so it's
easy to see which one failed.

[William Hesse, 2009-11-01 15:33:28]

LGTM.

http://codereview.chromium.org/342058/diff/1/4
File src/compiler.cc (right):

http://codereview.chromium.org/342058/diff/1/4#newcode844
Line 844: if (expr->is_prefix()) BAILOUT("Prefix CountOperation");
Putting an assert that expr->is_postfix in the platform-specific implementations
of code generation would make it easier to read them, and check them, correctly.

http://codereview.chromium.org/342058/diff/1/5
File src/x64/fast-codegen-x64.cc (right):

http://codereview.chromium.org/342058/diff/1/5#newcode963
Line 963: case Expression::kTest:
Could all the test contexts be implemented by a simple 
pop(rax)
Move(context, rax)?

[Kevin Millikin (Chromium), 2009-11-01 17:45:50]

http://codereview.chromium.org/342058/diff/1/5
File src/x64/fast-codegen-x64.cc (right):

http://codereview.chromium.org/342058/diff/1/5#newcode963
Line 963: case Expression::kTest:
On 2009/11/01 15:33:28, William Hesse wrote:
> Could all the test contexts be implemented by a simple 
> pop(rax)
> Move(context, rax)?
> 

The code would be simpler, at the cost of popping then pushing for the two
hybrid test contexts.

I'd leave it like this for now.  We'll clearly have to revisit value contexts
and break them out by where the value already is (or where it wants to be).