[BNNS] Chromium crashed after ADD operation was implemented

[Christywl]

Test Env: Chromium nightly build 70.0.3503.0 (8755e6b) Platform: Mac OS 10.13.6

Expected Result: No crash happens.

Actual Result: Chromium crashed after ADD operation was implemented:

Received signal 11 SEGV_MAPERR 000000000024
 [0x0001185b60ec]
 [0x0001185b5fe1]
 [0x7fff77280f5a]
 [0x7fa9ecd1c8c0]
 [0x0001172ee585]
 [0x0001172ee3c3]
 [0x0001172ff45f]
 [0x0001172fbd26]
 [0x000118b9f498]
 [0x000118ba3b41]
 [0x000118ba3374]
 [0x000118b9d5a1]
 [0x000118b9dc51]
 [0x000118addeb8]
 [0x000118505932]
 [0x0001185264df]
 [0x0001185269a8]
 [0x000118528b6a]
 [0x000118518bea]
 [0x00011852848f]
 [0x7fff4f05f8f1]
 [0x7fff4f11930c]
 [0x7fff4f042350]
 [0x7fff4f0417cd]
 [0x7fff4f041033]
 [0x7fff5113ee76]
 [0x0001185291cd]
 [0x000118527fae]
 [0x00011854af55]
 [0x00011c627fdc]
 [0x0001180fd129]
 [0x000119970401]
 [0x0001180fc2f4]
 [0x0001161e9803]
 [0x00010ec65131]
 [0x7fff76f72015]
 [0x000000000008]
[end of stack trace]

How to Reproduce:

1. Launch chromium and enable WebML flag
2. Visit:
   • https://brucedai.github.io/nt/test/issue-add.html?backend=bnns
   • https://brucedai.github.io/nt/test/add-broadcasting.html?backend=bnns

Note: Some ADD tests worked fine, and they didn't cause the crash issue: https://brucedai.github.io/nt/test/add.html?backend=bnns

[Christywl]

This issue was fixed on nightly build 022e2ff.