Generate JS operators using helper functions with thunks for operands.

Generate JS operators using helper functions with thunks for operands.

This removes a lot of boilerplate, yet complex, code with its occasional
inevitable errors.

Committed: https://code.google.com/p/dart/source/detail?r=9250

[Lasse Reichstein Nielsen, 2012-06-29 06:05:18]

This is a lower-impact attempt to simplify JS expression code generation. In the
longer run, the helper functions could be made to build an AST instead, if we
want that.

[Lasse Reichstein Nielsen, 2012-06-29 11:34:56]

If we can't go to a full AST right now, I think we should do this as an
intermediate step. It makes it much easier to write operator-code without having
to know the JS precedences.

https://chromiumcodereview.appspot.com/10697031/diff/1/lib/compiler/implement...
File lib/compiler/implementation/ssa/codegen.dart (right):

https://chromiumcodereview.appspot.com/10697031/diff/1/lib/compiler/implement...
lib/compiler/implementation/ssa/codegen.dart:303: void binary(String operator,
void lhs(), void rhs()) {
Could be called "infix". Could take operator as second argument if that's more
readable.

https://chromiumcodereview.appspot.com/10697031/diff/1/lib/compiler/implement...
lib/compiler/implementation/ssa/codegen.dart:328: * Generate code for a
JavaScript prefix operator.
Should add comment that the operator isn't checked for anything, and if it's a
word-operator (e.g., "typeof" or "void"), the caller should give it a tailing
space.

https://chromiumcodereview.appspot.com/10697031/diff/1/lib/compiler/implement...
lib/compiler/implementation/ssa/codegen.dart:1281: () => use(left,
expectedPrecedence),
Maybe I should add a "delayedUse(x) => () => use(x, expectedPrecedence);"
helper. And make literal delayed too.

https://chromiumcodereview.appspot.com/10697031/diff/1/lib/compiler/implement...
lib/compiler/implementation/ssa/codegen.dart:1282: () => buffer.add("null"));
should be "literal".

[floitsch, 2012-06-29 11:55:32]

LGTM.

https://chromiumcodereview.appspot.com/10697031/diff/1/lib/compiler/implement...
File lib/compiler/implementation/ssa/codegen.dart (right):

https://chromiumcodereview.appspot.com/10697031/diff/1/lib/compiler/implement...
lib/compiler/implementation/ssa/codegen.dart:678: binary("=", (){
But each closure on one line.

https://chromiumcodereview.appspot.com/10697031/diff/1/lib/compiler/implement...
lib/compiler/implementation/ssa/codegen.dart:1229: () => use(node.left,
expectedPrecedence),
indentation.

https://chromiumcodereview.appspot.com/10697031/diff/1/lib/compiler/implement...
lib/compiler/implementation/ssa/codegen.dart:1241: () => visitInvokeBinary(node,
op),
indendantion.

https://chromiumcodereview.appspot.com/10697031/diff/1/lib/compiler/implement...
lib/compiler/implementation/ssa/codegen.dart:1281: () => use(left,
expectedPrecedence),
On 2012/06/29 11:34:56, Lasse Reichstein Nielsen wrote:
> Maybe I should add a "delayedUse(x) => () => use(x, expectedPrecedence);"
> helper. And make literal delayed too.

I don't think that's necessary.

https://chromiumcodereview.appspot.com/10697031/diff/1/lib/compiler/implement...
lib/compiler/implementation/ssa/codegen.dart:1281: () => use(left,
expectedPrecedence),
I would define the closures first:
Function condition = () {
 ...
};
Function ifTrue = () {
 ...
};
...
conditional(condition, ifTrue, ifFalse);

https://chromiumcodereview.appspot.com/10697031/diff/1/lib/compiler/implement...
lib/compiler/implementation/ssa/codegen.dart:1624: generateAnd(thenGraph, () {
use(node.inputs[0],
move the closure in one line.

[Lasse Reichstein Nielsen, 2012-06-29 14:20:13]

https://chromiumcodereview.appspot.com/10697031/diff/1/lib/compiler/implement...
File lib/compiler/implementation/ssa/codegen.dart (right):

https://chromiumcodereview.appspot.com/10697031/diff/1/lib/compiler/implement...
lib/compiler/implementation/ssa/codegen.dart:678: binary("=", (){
On 2012/06/29 11:55:32, floitsch wrote:
> But each closure on one line.

Done.

https://chromiumcodereview.appspot.com/10697031/diff/1/lib/compiler/implement...
lib/compiler/implementation/ssa/codegen.dart:1229: () => use(node.left,
expectedPrecedence),
On 2012/06/29 11:55:32, floitsch wrote:
> indentation.

Done.

https://chromiumcodereview.appspot.com/10697031/diff/1/lib/compiler/implement...
lib/compiler/implementation/ssa/codegen.dart:1241: () => visitInvokeBinary(node,
op),
Done everywhere *cross fingers*.

https://chromiumcodereview.appspot.com/10697031/diff/1/lib/compiler/implement...
lib/compiler/implementation/ssa/codegen.dart:1281: () => use(left,
expectedPrecedence),
On 2012/06/29 11:55:32, floitsch wrote:
> I would define the closures first:
> Function condition = () {
>  ...
> };
> Function ifTrue = () {
>  ...
> };
> ...
> conditional(condition, ifTrue, ifFalse);

Done.

https://chromiumcodereview.appspot.com/10697031/diff/1/lib/compiler/implement...
lib/compiler/implementation/ssa/codegen.dart:1624: generateAnd(thenGraph, () {
use(node.inputs[0],
On 2012/06/29 11:55:32, floitsch wrote:
> move the closure in one line.

Done.