Basic type inference skeleton

Basic type inference skeleton

Committed: https://code.google.com/p/dart/source/detail?r=10328

[kasperl, 2012-08-07 08:03:42]

LGTM.

https://chromiumcodereview.appspot.com/10823184/diff/2001/dart/lib/compiler/i...
File dart/lib/compiler/implementation/types/types.dart (right):

https://chromiumcodereview.appspot.com/10823184/diff/2001/dart/lib/compiler/i...
dart/lib/compiler/implementation/types/types.dart:40: void storeType(Element
element, HInstruction instruction) {
It would be nice to not have the TypesTask know about HInstructions at all. As
we talked about it might be nicer if the TypesTask can give you back an element
for the guaranteed type of an element (if it has one) and then the SSA builder
can map that to the corresponding HType.

[ahe, 2012-08-07 08:32:14]

Thank you, Kasper.

https://chromiumcodereview.appspot.com/10823184/diff/2001/dart/lib/compiler/i...
File dart/lib/compiler/implementation/types/types.dart (right):

https://chromiumcodereview.appspot.com/10823184/diff/2001/dart/lib/compiler/i...
dart/lib/compiler/implementation/types/types.dart:40: void storeType(Element
element, HInstruction instruction) {
On 2012/08/07 08:03:43, kasperl wrote:
> It would be nice to not have the TypesTask know about HInstructions at all. As
> we talked about it might be nicer if the TypesTask can give you back an
element
> for the guaranteed type of an element (if it has one) and then the SSA builder
> can map that to the corresponding HType.

Done.

[polux, 2012-08-07 08:52:32]

lgtm

[ngeoffray, 2012-08-16 12:53:10]

DBC

https://chromiumcodereview.appspot.com/10823184/diff/6001/dart/lib/compiler/i...
File dart/lib/compiler/implementation/lib/core.dart (right):

https://chromiumcodereview.appspot.com/10823184/diff/6001/dart/lib/compiler/i...
dart/lib/compiler/implementation/lib/core.dart:42: void print(var obj) {
Why this change?

https://chromiumcodereview.appspot.com/10823184/diff/6001/dart/lib/compiler/i...
File dart/lib/compiler/implementation/ssa/builder.dart (right):

https://chromiumcodereview.appspot.com/10823184/diff/6001/dart/lib/compiler/i...
dart/lib/compiler/implementation/ssa/builder.dart:3299: if (element ===
builder.compiler.boolClass) return HType.BOOLEAN;
Should those be BOOLEAN_OR_NULL, ... ?

https://chromiumcodereview.appspot.com/10823184/diff/6001/dart/lib/compiler/i...
dart/lib/compiler/implementation/ssa/builder.dart:3302: // TODO(ahe): How to map
listClass to HType?
new HBoundedPotentialPrimitiveArray(element.computeType(), canBeNull: true)

(or something)

[ahe, 2012-08-16 17:26:53]

https://chromiumcodereview.appspot.com/10823184/diff/6001/dart/lib/compiler/i...
File dart/lib/compiler/implementation/lib/core.dart (right):

https://chromiumcodereview.appspot.com/10823184/diff/6001/dart/lib/compiler/i...
dart/lib/compiler/implementation/lib/core.dart:42: void print(var obj) {
On 2012/08/16 12:53:10, ngeoffray wrote:
> Why this change?

For hello world, I can infer that this method is only ever called with a string.
So the optimizer can eliminate the else branch. This means no call to toString.

https://chromiumcodereview.appspot.com/10823184/diff/6001/dart/lib/compiler/i...
File dart/lib/compiler/implementation/ssa/builder.dart (right):

https://chromiumcodereview.appspot.com/10823184/diff/6001/dart/lib/compiler/i...
dart/lib/compiler/implementation/ssa/builder.dart:3299: if (element ===
builder.compiler.boolClass) return HType.BOOLEAN;
On 2012/08/16 12:53:10, ngeoffray wrote:
> Should those be BOOLEAN_OR_NULL, ... ?

No. It has been inferred that it must be a bool. This is the "concrete" part of
concrete-type inference, and why it felt appropriate to use elements.

However, I think when Paul's changes land, we will probably switch to a cleaner
abstraction for concrete types.

See the discussion of concrete types vs abstract types in
http://labs.oracle.com/techrep/1996/smli_tr-96-52.pdf page 4.

https://chromiumcodereview.appspot.com/10823184/diff/6001/dart/lib/compiler/i...
dart/lib/compiler/implementation/ssa/builder.dart:3302: // TODO(ahe): How to map
listClass to HType?
On 2012/08/16 12:53:10, ngeoffray wrote:
> new HBoundedPotentialPrimitiveArray(element.computeType(), canBeNull: true)
> 
> (or something)

It can't be null and it will be a primitive array.