This function will find the closest ref node aliased to Reg that is
in an instruction preceding Inst. This could be used to identify the
hypothetical reaching def of Reg, if Reg was a member of Inst.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@297524 91177308-0d34-0410-b5e6-96231b3b80d8
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
When calculating kills, a register may be considered live because a part
of it is live, but if there is a use of that (whole) register, the whole
register (and its subregisters) need to be added to the live set.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292845 91177308-0d34-0410-b5e6-96231b3b80d8
Specifically avoid implicit conversions from/to integral types to
avoid potential errors when changing the underlying type. For example,
a typical initialization of a "full" mask was "LaneMask = ~0u", which
would result in a value of 0x00000000FFFFFFFF if the type was extended
to uint64_t.
Differential Revision: https://reviews.llvm.org/D27454
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289820 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
Each shadow only represents data flow that is restricted to its reaching
def. Propagating more than that could lead to spurious register liveness,
resulting in extra (incorrectly) block live-ins.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@283143 91177308-0d34-0410-b5e6-96231b3b80d8
Shadow uses need to be analyzed together, since each individual shadow
will only have a partial reaching def. All shadows together may cover
a given register ref, while each individual shadow may not.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@280855 91177308-0d34-0410-b5e6-96231b3b80d8
