- Wire the stack frame iterator to use stack maps for traversing objects if there are stack maps in…

- Wire the stack frame iterator to use stack maps for traversing objects if there are stack maps in the code object. If there are no stack maps it still does the old style stack frame traversal between fp and sp looking for tagged pointers.
- Added a mechanism to be able to iterate over the code space and look for a particular object.

- Remove registration of code objects into the code index table.
Committed: https://code.google.com/p/dart/source/detail?r=6302

[srdjan, 2012-03-28 21:56:35]

LGTM

https://chromiumcodereview.appspot.com/9791048/diff/7002/vm/pages.cc
File vm/pages.cc (right):

https://chromiumcodereview.appspot.com/9791048/diff/7002/vm/pages.cc#newcode227
vm/pages.cc:227: RawObject* obj = page->FindObject(visitor);
Add NoGC after call to FindObject.

https://chromiumcodereview.appspot.com/9791048/diff/7002/vm/pages.cc#newcode236
vm/pages.cc:236: RawObject* obj = page->FindObject(visitor);
ditto

https://chromiumcodereview.appspot.com/9791048/diff/7002/vm/raw_object.cc
File vm/raw_object.cc (right):

https://chromiumcodereview.appspot.com/9791048/diff/7002/vm/raw_object.cc#new...
vm/raw_object.cc:421: if (pc >= start_pc && pc < end_pc) {
Add parentheses. Maybe:

return (pc >= start_pc) && (pc < end_pc);

https://chromiumcodereview.appspot.com/9791048/diff/7002/vm/raw_object.cc#new...
vm/raw_object.cc:451: uint8_t byte = ptr()->data_[byte_offset];
All of locals can be const.

https://chromiumcodereview.appspot.com/9791048/diff/7002/vm/stack_frame.cc
File vm/stack_frame.cc (right):

https://chromiumcodereview.appspot.com/9791048/diff/7002/vm/stack_frame.cc#ne...
vm/stack_frame.cc:80: // frame slots which are marked as having objects.
Can this part be tested?

[siva, 2012-03-29 19:01:27]

Addressed review comments and added a unit test case for the stack traversal
with stack maps code.

https://chromiumcodereview.appspot.com/9791048/diff/7002/vm/pages.cc
File vm/pages.cc (right):

https://chromiumcodereview.appspot.com/9791048/diff/7002/vm/pages.cc#newcode227
vm/pages.cc:227: RawObject* obj = page->FindObject(visitor);
I have added an assertion that this function should only be called inside a
NoGCScope context.

On 2012/03/28 21:56:36, srdjan wrote:
> Add NoGC after call to FindObject.

https://chromiumcodereview.appspot.com/9791048/diff/7002/vm/pages.cc#newcode236
vm/pages.cc:236: RawObject* obj = page->FindObject(visitor);
ditto.

On 2012/03/28 21:56:36, srdjan wrote:
> ditto

https://chromiumcodereview.appspot.com/9791048/diff/7002/vm/raw_object.cc
File vm/raw_object.cc (right):

https://chromiumcodereview.appspot.com/9791048/diff/7002/vm/raw_object.cc#new...
vm/raw_object.cc:421: if (pc >= start_pc && pc < end_pc) {
On 2012/03/28 21:56:36, srdjan wrote:
> Add parentheses. Maybe:
> 
> return (pc >= start_pc) && (pc < end_pc);

Done.

https://chromiumcodereview.appspot.com/9791048/diff/7002/vm/raw_object.cc#new...
vm/raw_object.cc:451: uint8_t byte = ptr()->data_[byte_offset];
On 2012/03/28 21:56:36, srdjan wrote:
> All of locals can be const.

Done.

https://chromiumcodereview.appspot.com/9791048/diff/7002/vm/stack_frame.cc
File vm/stack_frame.cc (right):

https://chromiumcodereview.appspot.com/9791048/diff/7002/vm/stack_frame.cc#ne...
vm/stack_frame.cc:80: // frame slots which are marked as having objects.
Added a unit test case for this by generating a stackmap for   an unoptimized
code blob and adding it to the code object.
The unit test forces a GC and traverses the stack at that point using the stack
map.

On 2012/03/28 21:56:36, srdjan wrote:
> Can this part be tested?

[Ivan Posva, 2012-04-03 23:28:50]

LGTM with comments.

-Ivan

https://chromiumcodereview.appspot.com/9791048/diff/29001/vm/raw_object.cc
File vm/raw_object.cc (right):

https://chromiumcodereview.appspot.com/9791048/diff/29001/vm/raw_object.cc#ne...
vm/raw_object.cc:239: ObjectKind instance_kind =
raw_class->ptr()->instance_kind_;
This code could be inlined into the ContainsPC method.

https://chromiumcodereview.appspot.com/9791048/diff/29001/vm/raw_object.cc#ne...
vm/raw_object.cc:377: RawStackmap* RawCode::GetStackmap(uword pc) const {
Move this code into the Code object?

https://chromiumcodereview.appspot.com/9791048/diff/29001/vm/raw_object.cc#ne...
vm/raw_object.cc:678: intptr_t RawArray::Length() const {
inline into uses

https://chromiumcodereview.appspot.com/9791048/diff/29001/vm/stack_frame.cc
File vm/stack_frame.cc (right):

https://chromiumcodereview.appspot.com/9791048/diff/29001/vm/stack_frame.cc#n...
vm/stack_frame.cc:18: return RawInstructions::ContainsPC(obj, pc_);
ASSERT that you are getting a RawInstructions object. It might be OK to have it
in the RawInstructions::ContainsPC method.

https://chromiumcodereview.appspot.com/9791048/diff/29001/vm/stack_frame.cc#n...
vm/stack_frame.cc:37: RawObject* obj =
isolate->heap()->FindObjectInCodeSpace(&visitor);
How about returning RawInstructions* from FindObjectInCodeSpace?

[siva, 2012-04-07 01:22:55]

https://chromiumcodereview.appspot.com/9791048/diff/29001/vm/raw_object.cc
File vm/raw_object.cc (right):

https://chromiumcodereview.appspot.com/9791048/diff/29001/vm/raw_object.cc#ne...
vm/raw_object.cc:239: ObjectKind instance_kind =
raw_class->ptr()->instance_kind_;
On 2012/04/03 23:28:50, Ivan Posva wrote:
> This code could be inlined into the ContainsPC method.

Done.

https://chromiumcodereview.appspot.com/9791048/diff/29001/vm/raw_object.cc#ne...
vm/raw_object.cc:377: RawStackmap* RawCode::GetStackmap(uword pc) const {
Done.

Used special stack handles in the DartFrame code to be able
to access this code using the handle. These stack handles
are not visited.

On 2012/04/03 23:28:50, Ivan Posva wrote:
> Move this code into the Code object?

https://chromiumcodereview.appspot.com/9791048/diff/29001/vm/raw_object.cc#ne...
vm/raw_object.cc:678: intptr_t RawArray::Length() const {
Not needed any more as the GetStackmap code was moved to a handle based one.

On 2012/04/03 23:28:50, Ivan Posva wrote:
> inline into uses

https://chromiumcodereview.appspot.com/9791048/diff/29001/vm/stack_frame.cc
File vm/stack_frame.cc (right):

https://chromiumcodereview.appspot.com/9791048/diff/29001/vm/stack_frame.cc#n...
vm/stack_frame.cc:18: return RawInstructions::ContainsPC(obj, pc_);
The assertion is done in ContainsPC.

On 2012/04/03 23:28:50, Ivan Posva wrote:
> ASSERT that you are getting a RawInstructions object. It might be OK to have
it
> in the RawInstructions::ContainsPC method.

https://chromiumcodereview.appspot.com/9791048/diff/29001/vm/stack_frame.cc#n...
vm/stack_frame.cc:37: RawObject* obj =
isolate->heap()->FindObjectInCodeSpace(&visitor);
On 2012/04/03 23:28:50, Ivan Posva wrote:
> How about returning RawInstructions* from FindObjectInCodeSpace?

Done.