If operands are loaded as unsigned 32-bit integer, they need to be sign extended to 64 bits.

TEST=cctest/test-run-machops/RunWord32AndAndWord32ShrP, cctest/test-run-machops/RunWord32OrP,
cctest/test-run-machops/RunWord32ShrP, cctest/test-run-machops/RunWord32XorP

BUG=

Review-Url: https://codereview.chromium.org/2147883002
Cr-Commit-Position: refs/heads/master@{#37705}