[wasm] Refactor encoder.h to use a proper buffer and remove OldFunctions section.

[wasm] Refactor encoder.h to use a proper buffer and remove OldFunctions section.

This removes the last use of the old_functions section, which greatly
simplifies encoding.

R=bradnelson@chromium.org,aseemgarg@chromium.org,mtrofin@chromium.org

BUG=

Committed: https://crrev.com/3412af0b40764be2d1095f16ef70bb3749b4d8e5
Cr-Commit-Position: refs/heads/master@{#36523}

[bradnelson, 2016-05-25 14:51:23]

lgtm

https://codereview.chromium.org/2014533003/diff/1/src/wasm/encoder.cc
File src/wasm/encoder.cc (right):

https://codereview.chromium.org/2014533003/diff/1/src/wasm/encoder.cc#newcode167
src/wasm/encoder.cc:167: locals_.Emit(*ptr);
Yeah, yuck.

https://codereview.chromium.org/2014533003/diff/1/src/wasm/encoder.h
File src/wasm/encoder.h (right):

https://codereview.chromium.org/2014533003/diff/1/src/wasm/encoder.h#newcode23
src/wasm/encoder.h:23: class ZoneBuffer : public ZoneObject {
How about in a separate file? Or you leaning on the compiler to inline?

https://codereview.chromium.org/2014533003/diff/1/src/wasm/encoder.h#newcode95
src/wasm/encoder.h:95: size_t new_size = 4096 + (end_ - buffer_) * 3;
Are all the cool kids doing 3 instead of 2 these days ?

https://codereview.chromium.org/2014533003/diff/1/src/wasm/encoder.h#newcode104
src/wasm/encoder.h:104: byte** pos_ptr() { return &pos_; }
That seems a rather leaky abstraction... reserve judgement until I see where
it's used.

https://codereview.chromium.org/2014533003/diff/1/test/unittests/wasm/module-...
File test/unittests/wasm/module-decoder-unittest.cc (left):

https://codereview.chromium.org/2014533003/diff/1/test/unittests/wasm/module-...
test/unittests/wasm/module-decoder-unittest.cc:324: TEST_F(WasmModuleVerifyTest,
FunctionWithoutSig) {
Why drop these, as they're brittle?

[titzer, 2016-05-25 15:40:21]

https://codereview.chromium.org/2014533003/diff/1/src/wasm/encoder.h
File src/wasm/encoder.h (right):

https://codereview.chromium.org/2014533003/diff/1/src/wasm/encoder.h#newcode23
src/wasm/encoder.h:23: class ZoneBuffer : public ZoneObject {
On 2016/05/25 14:51:23, bradnelson wrote:
> How about in a separate file? Or you leaning on the compiler to inline?

I think we can pull this out to its own header in another CL. I'd call that
header "encoder.h" and rename this one "module-encoder.h"

https://codereview.chromium.org/2014533003/diff/1/src/wasm/encoder.h#newcode95
src/wasm/encoder.h:95: size_t new_size = 4096 + (end_ - buffer_) * 3;
On 2016/05/25 14:51:23, bradnelson wrote:
> Are all the cool kids doing 3 instead of 2 these days ?

Growth factors are hard. I always felt like 2x was too low, but I didn't really
tune here.

https://codereview.chromium.org/2014533003/diff/1/src/wasm/encoder.h#newcode104
src/wasm/encoder.h:104: byte** pos_ptr() { return &pos_; }
On 2016/05/25 14:51:23, bradnelson wrote:
> That seems a rather leaky abstraction... reserve judgement until I see where
> it's used.

Yeah, it's because of a special case with the local decls encoding. The choices
were either to expose it as a double pointer or have a read and a bump. I did
both this and this was a tiny bit shorter, but can fix later.

[titzer, 2016-05-25 15:40:31]

The CQ bit was checked by titzer@chromium.org

[commit-bot: I haz the power, 2016-05-25 15:40:41]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/2014533003/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/2014533003/1

[commit-bot: I haz the power, 2016-05-25 16:12:20]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-05-25 16:13:57]

Description was changed from

==========
[wasm] Refactor encoder.h to use a proper buffer and remove OldFunctions
section.

This removes the last use of the old_functions section, which greatly
simplifies encoding.

R=bradnelson@chromium.org,aseemgarg@chromium.org,mtrofin@chromium.org

BUG=
==========

to

==========
[wasm] Refactor encoder.h to use a proper buffer and remove OldFunctions
section.

This removes the last use of the old_functions section, which greatly
simplifies encoding.

R=bradnelson@chromium.org,aseemgarg@chromium.org,mtrofin@chromium.org

BUG=

Committed: https://crrev.com/3412af0b40764be2d1095f16ef70bb3749b4d8e5
Cr-Commit-Position: refs/heads/master@{#36523}
==========

[commit-bot: I haz the power, 2016-05-25 16:13:58]

Patchset 1 (id:??) landed as
https://crrev.com/3412af0b40764be2d1095f16ef70bb3749b4d8e5
Cr-Commit-Position: refs/heads/master@{#36523}