Revert "Revert "temporary work-around for the bogus "loop unroll limit reached" failures.""

This reverts commit 9fbd55aebb401673daf447bfe9fde269545c637e.
MIPS: Cosmetic fix for interpreter.
Merge branch 'master' into v2.1
Add trace stitching.
Revert "added Mike Pall's temporary workaround for fixing a segmentation fault when a lua error is thrown."

This reverts commit c865570245a4371bd9dcd157e1e3deb437651b3c.
Merge branch 'v2.1' into v2.1-agentzh
Show trailing NYI item for stitched trace with -jv.
Merge branch 'v2.1' into v2.1-agentzh