Optimize Ref_toString().

[nnethercote]

I have a large PDF where this function is called 1.6 million times
during loading. Minimizing the string concatenations reduces the
cumulative allocations done by Firefox within this function from 113 MB
to 48 MB.

[timvandermeij]

/botio test

[pdfjsbot]

From: Bot.io (Linux)

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Received

Command cmd_test from @timvandermeij received. Current queue size: 0

Live output at: http://107.21.233.14:8877/74844d11bc600ee/output.txt

[pdfjsbot]

From: Bot.io (Windows)

---

Received

Command cmd_test from @timvandermeij received. Current queue size: 0

Live output at: http://107.22.172.223:8877/5b588c684a22b53/output.txt

[pdfjsbot]

From: Bot.io (Windows)

---

Success

Full output at http://107.22.172.223:8877/5b588c684a22b53/output.txt

Total script time: 21.23 mins

• Font tests: Passed
• Unit tests: Passed
• Regression tests: Passed

[pdfjsbot]

From: Bot.io (Linux)

---

Success

Full output at http://107.21.233.14:8877/74844d11bc600ee/output.txt

Total script time: 23.32 mins

• Font tests: Passed
• Unit tests: Passed
• Regression tests: Passed

[timvandermeij]

/botio-linux preview

[pdfjsbot]

From: Bot.io (Linux)

---

Received

Command cmd_preview from @timvandermeij received. Current queue size: 0

Live output at: http://107.21.233.14:8877/c7b4ca50000830b/output.txt

[pdfjsbot]

From: Bot.io (Linux)

---

Success

Full output at http://107.21.233.14:8877/c7b4ca50000830b/output.txt

Total script time: 0.75 mins

Published

• Viewer: http://107.21.233.14:8877/c7b4ca50000830b/web/viewer.html
• B2G Viewer: http://107.21.233.14:8877/c7b4ca50000830b/extensions/b2g/content/web/viewer.html
• Extension: http://107.21.233.14:8877/c7b4ca50000830b/extensions/firefox/pdf.js.xpi
• Extension (AMO): http://107.21.233.14:8877/c7b4ca50000830b/extensions/firefox/pdf.js.amo.xpi

[nnethercote]

See http://njn.valgrind.org/book.pdf. Warning: it's a 20 MiB file.

[yurydelendik]

Thanks