This gets us closer to being able to remove LiveVariables entirely which is where dead instructions are currently tagged as such.
Reviewed by Jakob Olesen
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210132 91177308-0d34-0410-b5e6-96231b3b80d8
define below all header includes in the lib/CodeGen/... tree. While the
current modules implementation doesn't check for this kind of ODR
violation yet, it is likely to grow support for it in the future. It
also removes one layer of macro pollution across all the included
headers.
Other sub-trees will follow.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206837 91177308-0d34-0410-b5e6-96231b3b80d8
for use with C++11 range-based for-loops.
The gist of phase 1 is to remove the skipInstruction() and skipBundle()
methods from these iterators, instead splitting each iterator into a version
that walks operands, a version that walks instructions, and a version that
walks bundles. This has the result of making some "clever" loops in lib/CodeGen
more verbose, but also makes their iterator invalidation characteristics much
more obvious to the casual reader. (Making them concise again in the future is a
good motivating case for a pre-incrementing range adapter!)
Phase 2 of this undertaking with consist of removing the getOperand() method,
and changing operator*() of the operand-walker to return a MachineOperand&. At
that point, it should be possible to add range views for them that work as one
might expect.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203757 91177308-0d34-0410-b5e6-96231b3b80d8
This is slightly more interesting than the previous batch of changes.
Specifically:
1. We refactor getSpillWeight to take a MachineBlockFrequencyInfo (MBFI)
object. This enables us to completely encapsulate the actual manner we
use the MachineBlockFrequencyInfo to get our spill weights. This yields
cleaner code since one does not need to fetch the actual block frequency
before getting the spill weight if all one wants it the spill weight. It
also gives us access to entry frequency which we need for our
computation.
2. Instead of having getSpillWeight take a MachineBasicBlock (as one
might think) to look up the block frequency via the MBFI object, we
instead take in a MachineInstr object. The reason for this is that the
method is supposed to return the spill weight for an instruction
according to the comments around the function.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197296 91177308-0d34-0410-b5e6-96231b3b80d8
Previously LiveInterval has been used, but having a spill weight and
register number is unnecessary for a register unit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192397 91177308-0d34-0410-b5e6-96231b3b80d8
This makes the API a bit more natural to use and makes it easier to make
LiveRanges implementation details private.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192394 91177308-0d34-0410-b5e6-96231b3b80d8
LiveRange just manages a list of segments and a list of value numbers
now as LiveInterval did previously, but without having details like spill
weight or a fixed register number.
LiveInterval is now a subclass of LiveRange and simply adds the spill weight
and the register number.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192393 91177308-0d34-0410-b5e6-96231b3b80d8
The Segment struct contains a single interval; multiple instances of this struct
are used to construct a live range, but the struct is not a live range by
itself.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192392 91177308-0d34-0410-b5e6-96231b3b80d8
When new virtual registers are created during splitting/spilling, defer
creation of the live interval until we need to use the live interval.
Along with the recent commits to notify LiveRangeEdit when new virtual
registers are created, this makes it possible for functions like
TargetInstrInfo::loadRegFromStackSlot() and
TargetInstrInfo::storeRegToStackSlot() to create multiple virtual
registers as part of the process of generating loads/stores for
different register classes, and then have the live intervals for those
new registers computed when they are needed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188437 91177308-0d34-0410-b5e6-96231b3b80d8
The main advantages here are way better heuristics, taking into account not
just loop depth but also __builtin_expect and other static heuristics and will
eventually learn how to use profile info. Most of the work in this patch is
pushing the MachineBlockFrequencyInfo analysis into the right places.
This is good for a 5% speedup on zlib's deflate (x86_64), there were some very
unfortunate spilling decisions in its hottest loop in longest_match(). Other
benchmarks I tried were mostly neutral.
This changes register allocation in subtle ways, update the tests for it.
2012-02-20-MachineCPBug.ll was deleted as it's very fragile and the instruction
it looked for was gone already (but the FileCheck pattern picked up unrelated
stuff).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@184105 91177308-0d34-0410-b5e6-96231b3b80d8
To find the last use of a register unit, start from the bottom and scan
upwards until a user is found.
<rdar://problem/13353090>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176706 91177308-0d34-0410-b5e6-96231b3b80d8
Eric Christopher
Pete Cooper
Chandler Carruth
Craig Topper
Owen Anderson
Benjamin Kramer
Michael Gottesman
Aaron Ballman
Matthias Braun
Mark Lacey
Jakob Stoklund Olesen
Andrew Trick
Chad Rosier
Cameron Zwarich