For large programs this function can take significant amounts of time.
Let it abort gracefully when the program is too complex.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296662 91177308-0d34-0410-b5e6-96231b3b80d8
Defining nodes should not alias with one another, while clobbering
nodes can. When pushing defs on stacks, push clobbers first, link
non-clobbering defs, then push the defs.
The data flow in a statement is now: uses -> clobbers -> defs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@295356 91177308-0d34-0410-b5e6-96231b3b80d8
This required reengineering of some of the part of liveness calculation,
including fixing some issues caused by the limitations of the previous
approach. The current code is not necessarily the fastest, but it should
be functionally correct (at least more so than before). The compile-time
performance will be addressed in the future.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@284609 91177308-0d34-0410-b5e6-96231b3b80d8
Use PackedRegisterRef to store the register information in the graph nodes.
This commit also removes support for virtual registers. It has never been
tested or used. It will be possible to add it back if there is a need.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@284255 91177308-0d34-0410-b5e6-96231b3b80d8
