Added test cases for truncating stores.

Review URL: https://codereview.chromium.org/741643003

Cr-Commit-Position: refs/heads/master@{#25474}
[turbofan] Recognize sign extension of 8-bit and 16-bit values on arm64.

R=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/730183005

Cr-Commit-Position: refs/heads/master@{#25475}
Fix RegExp.source for uncompiled regexp.

R=jkummerow@chromium.org
BUG=435825
LOG=N

Review URL: https://codereview.chromium.org/753983002

Cr-Commit-Position: refs/heads/master@{#25476}
[turbofan] Dump graph in RPO order as text.

R=bmeurer@chromium.org
BUG=

Review URL: https://codereview.chromium.org/754803002

Cr-Commit-Position: refs/heads/master@{#25477}
Don't verify evacuation when it is not completed.

BUG=

Review URL: https://codereview.chromium.org/756553002

Cr-Commit-Position: refs/heads/master@{#25478}
[turbofan] Combine Word32And with Int32Add and negative power of two.

TEST=unittests
R=jarin@chromium.org

Review URL: https://codereview.chromium.org/749233002

Cr-Commit-Position: refs/heads/master@{#25479}