supersize: Tweak diff symbol matching for generated symbols

supersize: Tweak diff symbol matching for generated symbols

E.g. CSWTCH.61 and CSWTCH.62 will now match as long as they are in the
same object file.

BUG=708865, 717550
Review-Url: https://codereview.chromium.org/2857153002
Cr-Commit-Position: refs/heads/master@{#469045}
Committed: https://chromium.googlesource.com/chromium/src/+/47f9431d5a69ae9e81faa6472d8b5a188eb63242

[agrieve, 2017-05-03 14:37:58]

Description was changed from

==========
supersize: Tweak diff symbol matching for generated symbols

E.g. CSWTCH.61 and CSWTCH.62 will now match as long as they are in the
same object file.

BUG=708865,717550
==========

to

==========
supersize: Tweak diff symbol matching for generated symbols

E.g. CSWTCH.61 and CSWTCH.62 will now match as long as they are in the
same object file.

BUG=708865,717550
==========

[agrieve, 2017-05-03 14:37:58]

agrieve@chromium.org changed reviewers:
+ estevenson@chromium.org

[agrieve, 2017-05-03 14:38:04]

On 2017/05/03 14:37:58, agrieve wrote:
> mailto:agrieve@chromium.org changed reviewers:
> + mailto:estevenson@chromium.org

🐝

[estevenson, 2017-05-03 17:29:06]

lgtm

https://codereview.chromium.org/2857153002/diff/1/tools/binary_size/libsupers...
File tools/binary_size/libsupersize/diff.py (right):

https://codereview.chromium.org/2857153002/diff/1/tools/binary_size/libsupers...
tools/binary_size/libsupersize/diff.py:27: if name:
nit: this check seems superfluous since the rest of the function depends on
|name| anyways.

https://codereview.chromium.org/2857153002/diff/1/tools/binary_size/libsupers...
tools/binary_size/libsupersize/diff.py:38: name = re.sub(r'[.0-9]', '', name)  #
Strip out all numbers and dots.
Just to confirm I understand:

On Linux there are a bunch of .L__unnamed_XXXX, and since the names presumably
aren't stable there's no way for us to capture changes in these symbols. So
we're just assuming based on order that two symbols with the same keys are
deltas of each other right?

[agrieve, 2017-05-03 18:27:08]

https://codereview.chromium.org/2857153002/diff/1/tools/binary_size/libsupers...
File tools/binary_size/libsupersize/diff.py (right):

https://codereview.chromium.org/2857153002/diff/1/tools/binary_size/libsupers...
tools/binary_size/libsupersize/diff.py:27: if name:
On 2017/05/03 17:29:06, estevenson wrote:
> nit: this check seems superfluous since the rest of the function depends on
> |name| anyways.

Done.

https://codereview.chromium.org/2857153002/diff/1/tools/binary_size/libsupers...
tools/binary_size/libsupersize/diff.py:38: name = re.sub(r'[.0-9]', '', name)  #
Strip out all numbers and dots.
On 2017/05/03 17:29:06, estevenson wrote:
> Just to confirm I understand:
> 
> On Linux there are a bunch of .L__unnamed_XXXX, and since the names presumably
> aren't stable there's no way for us to capture changes in these symbols. So
> we're just assuming based on order that two symbols with the same keys are
> deltas of each other right?

Updated the pydoc to make confirm the "why".

But yeah, I don't know that it will work all that well for the linux symbols
since the example you pasted showed them also varying on size. It should work
well for symbols found on android like:

+       44 r@0x2a13ba8  24     
obj/third_party/WebKit/Source/platform/platform/RecordingImageBufferSurface.o
               CSWTCH.61
-       20 r@0x2a0f9b8  -24    
obj/third_party/WebKit/Source/platform/platform/RecordingImageBufferSurface.o
               CSWTCH.62
-        4 r@0x2b58888  -16    
obj/third_party/WebKit/Source/modules/vr/libvr.a(VRDisplay.o)
               ._468
+       20 r@0x2b5ca88  16     
obj/third_party/WebKit/Source/modules/vr/libvr.a(VRDisplay.o)
               ._470
-        4 r@0x2b7e148  -16    
obj/components/history/content/browser/libbrowser.a(download_conversions.o)
               CSWTCH.29
-      -12 r@0x2a101c0  -16    
obj/third_party/WebKit/Source/platform/platform/SkiaUtils.o
               CSWTCH.31
+        4 r@0x2a143a0  16     
obj/third_party/WebKit/Source/platform/platform/SkiaUtils.o
               CSWTCH.32
+       20 r@0x2b7e120  16      obj/chrome/browser/ui/libui.a(page_info_ui.o)
               CSWTCH.34

[agrieve, 2017-05-03 18:27:36]

The CQ bit was checked by agrieve@chromium.org

[agrieve, 2017-05-03 18:27:37]

The patchset sent to the CQ was uploaded after l-g-t-m from
estevenson@chromium.org
Link to the patchset: https://codereview.chromium.org/2857153002/#ps20001
(title: "review")

[commit-bot: I haz the power, 2017-05-03 18:28:40]

CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-05-03 18:41:10]

CQ is committing da patch.

Bot data: {"patchset_id": 20001, "attempt_start_ts": 1493836056953180,
"parent_rev": "0a8ca0d1e3ac86cd1d0955fc66a43aaa1eaf7393", "commit_rev":
"47f9431d5a69ae9e81faa6472d8b5a188eb63242"}

[commit-bot: I haz the power, 2017-05-03 18:41:31]

Description was changed from

==========
supersize: Tweak diff symbol matching for generated symbols

E.g. CSWTCH.61 and CSWTCH.62 will now match as long as they are in the
same object file.

BUG=708865,717550
==========

to

==========
supersize: Tweak diff symbol matching for generated symbols

E.g. CSWTCH.61 and CSWTCH.62 will now match as long as they are in the
same object file.

BUG=708865,717550

Review-Url: https://codereview.chromium.org/2857153002
Cr-Commit-Position: refs/heads/master@{#469045}
Committed:
https://chromium.googlesource.com/chromium/src/+/47f9431d5a69ae9e81faa6472d8b...
==========

[commit-bot: I haz the power, 2017-05-03 18:41:33]

Committed patchset #2 (id:20001) as
https://chromium.googlesource.com/chromium/src/+/47f9431d5a69ae9e81faa6472d8b...