Currently, when lowering switch statement and a new basic block is built for jump table / bit test header, the edge to this new block is not assigned with a correct weight. This patch collects the edge weight from all its successors and assign this sum of weights to the edge (and also the other fall-through edge). Test cases are adjusted accordingly.
Differential Revision: http://reviews.llvm.org/D12166#fae6eca7
llvm-svn: 246104
points.
There is an infinite loop that can occur in Shrink Wrapping while searching
for the Save/Restore points.
Part of this search checks whether the save/restore points are located in
different loop nests and if so, uses the (post) dominator trees to find the
immediate (post) dominator blocks. However, if the current block does not have
any immediate (post) dominators then this search will result in an infinite
loop. This can occur in code containing an infinite loop.
The modification checks whether the immediate (post) dominator is different from
the current save/restore block. If it is not, then the search terminates and the
current location is not considered as a valid save/restore point for shrink wrapping.
Phabricator: http://reviews.llvm.org/D11607
llvm-svn: 244247
With this patch the x86 backend is now shrink-wrapping capable
and this functionality can be tested by using the
-enable-shrink-wrap switch.
The next step is to make more test and enable shrink-wrapping by
default for x86.
Related to <rdar://problem/20821487>
llvm-svn: 238293
Cong Hou