Steps to reproduce:
1. Open user attached project
2. Build & Run
3. Observe the pink cube

Expected result: Shader compiler should not emit wrong code when using "sign" intrinsic

Reproduced in: 2019.2.0a2, 2018.3.3f1, 2018.3.0b9
Not reproduced in: 2018.3.0b8, 2018.1.9f2, 2017.4.19f1
Regression since: 2018.3.0b9

Fixed in: 2019.2.0a5, 2019.1.0b3, 2018.3.6f1

Tested devices:
Reproduced:
VLNQA00058, Sony Xperia Z (C6603), Android 4.4.4, CPU: Snapdragon S4 Plus MSM8960, GPU: Adreno (TM) 320
VLNQA00140, Samsung Galaxy S4 (GT-I9505), Android 5.0.1, CPU: Snapdragon S4 Plus MSM8960, GPU: Adreno (TM) 320
VLNQA00108, Lge LG Leon 4G LTE (LG-H340n), Android 5.0.1, CPU: Snapdragon 410 MSM8916, GPU: Adreno (TM) 306
VLNQA00030, Lge LG G2 (LG-D802), Android 4.4.2, CPU: Snapdragon 800 MSM8974, GPU: Adreno (TM) 330
Not reproduced:
VLNQA00003, Razer Razer Phone (Phone), Android 7.1.1, CPU: Snapdragon 835 MSM8998, GPU: Adreno (TM) 540
VLNQA00146, Htc 10 (HTC 10), Android 7.0, CPU: Snapdragon 820 MSM8996, GPU: Adreno (TM) 530
VLNQA00048, Samsung Galaxy S3 (GT-I9300), Android 4.3, CPU: Exynos 4 Quad 4412, GPU: Mali-400 MP