Add -reorder-basic-blocks option and fix nop insertion
1. Basic block reordering can be enabled with -reorder-basic-blocks option enabled.
Blocks will be sorted according to the Reversed Post Traversal Order, but the next
node to visit among all candidate children nodes is selected 'randomly'.
Example:
A
/ \
B C
\ /
D
This CFG can generate two possible layouts:
A-B-C-D or A-C-B-D
2. Fix nop insetion
Add checks to avoiding insertions in empty basic blocks(dead blocks) and bundle locked instructions.
BUG=
R=jpp@chromium.org, jvoung@chromium.org, stichnot@chromium.org
Review URL: https://codereview.chromium.org/1255303004.
8 files changed