The VNInfo::HAS_PHI_KILL is only half supported. We precompute it in
LiveIntervalAnalysis, but it isn't properly updated by live range
splitting and functions like shrinkToUses().
It is only used in one place: RegisterCoalescer::removeCopyByCommutingDef().
This patch changes that function to use a new LiveIntervals::hasPHIKill()
function that computes the flag for a given value number.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@161254 91177308-0d34-0410-b5e6-96231b3b80d8
This option replaces the existing live interval computation with one
based on LiveRangeCalc.cpp. The new algorithm does not depend on
LiveVariables, and it can be run at any time, before or after leaving
SSA form.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160892 91177308-0d34-0410-b5e6-96231b3b80d8
With regunit liveness permanently enabled, this function would always
return true.
Also remove now obsolete code for checking physreg interference.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159006 91177308-0d34-0410-b5e6-96231b3b80d8
Live intervals for regunits and virtual registers are stored separately,
and physreg live intervals are going away.
To visit the live ranges of all virtual registers, use this pattern
instead:
for (unsigned i = 0, e = MRI->getNumVirtRegs(); i != e; ++i) {
unsigned Reg = TargetRegisterInfo::index2VirtReg(i);
if (MRI->reg_nodbg_empty(Reg))
continue;
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158879 91177308-0d34-0410-b5e6-96231b3b80d8
Regunit live ranges are computed on demand, so when mi-sched calls
handleMove, some regunits may not have live ranges yet.
That makes updating them easier: Just skip the non-existing ranges. They
will be computed correctly from the rescheduled machine code when they
are needed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158831 91177308-0d34-0410-b5e6-96231b3b80d8
Instead of computing a live interval per physreg, LiveIntervals can
compute live intervals per register unit. This makes impossible the
confusing situation where aliasing registers could have overlapping live
intervals. It should also make fixed interferernce checking cheaper
since registers have fewer register units than aliases.
Live intervals for regunits are computed on demand, using MRI use-def
chains and the new LiveRangeCalc class. Only regunits live in to ABI
blocks are precomputed during LiveIntervals::runOnMachineFunction().
The regunit liveness computations don't depend on LiveVariables.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158029 91177308-0d34-0410-b5e6-96231b3b80d8
It is an old function that does a lot more than required by
CalcSpillWeights, which was the only remaining caller.
The isRematerializable() function never actually sets the isLoad
argument, so don't try to compute that.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157973 91177308-0d34-0410-b5e6-96231b3b80d8
bundles. This method takes a bundle start and an MI being bundled, and makes
the intervals for the MI's operands appear to start/end on the bundle start.
Also fixes some minor cosmetic issues (whitespace, naming convention) in the
HMEditor code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151099 91177308-0d34-0410-b5e6-96231b3b80d8
any changes.
Internally this adds a private inner class HMEditor, to LiveIntervals. HMEditor provides
an API for updating live intervals when code is moved or bundled.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150826 91177308-0d34-0410-b5e6-96231b3b80d8
No looping and binary searches necessary.
Return a pointer to the containing block instead of just a bool.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150218 91177308-0d34-0410-b5e6-96231b3b80d8
Build an ordered vector of register mask operands (i.e., calls) when
computing live intervals. Provide a checkRegMaskInterference() function
that computes a bit mask of usable registers for a live range.
This is a quick way of determining of a live range crosses any calls,
and restricting it to the callee saved registers if it does.
Previously, we had to discover call clobbers for each candidate register
independently.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150077 91177308-0d34-0410-b5e6-96231b3b80d8
LiveIntervalAnalysis has a number of functions that simply forward to
SlotIndexes. Since SlotIndexes is a stand-alone analysis now, clients
should really refer to it directly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149921 91177308-0d34-0410-b5e6-96231b3b80d8
If a value is defined by a COPY, that instuction can easily and cheaply
be found by getInstructionFromIndex(VNI->def).
This reduces the size of VNInfo from 24 to 16 bytes, and improves
llc compile time by 3%.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149763 91177308-0d34-0410-b5e6-96231b3b80d8
around within a basic block while maintaining live-intervals.
Updated ScheduleTopDownLive in MachineScheduler.cpp to use the moveInstr API
when reordering MIs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149147 91177308-0d34-0410-b5e6-96231b3b80d8
Delete the alternative implementation in LiveIntervalAnalysis.
These functions computed the same thing, but SplitAnalysis caches the
result.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147911 91177308-0d34-0410-b5e6-96231b3b80d8
I have convinced myself that it can only happen when a phi value dies. When it
happens, allocate new virtual registers for the components.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127827 91177308-0d34-0410-b5e6-96231b3b80d8
Simplify the spill weight calculation a bit by bypassing
getApproximateInstructionCount() and using LiveInterval::getSize() directly.
This changes the computed spill weights, but only by a constant factor in each
function. It should not affect how spill weights compare against each other, and
so it shouldn't affect code generation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125530 91177308-0d34-0410-b5e6-96231b3b80d8
This is a lot easier than trying to get kill flags right during live range
splitting and rematerialization.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125113 91177308-0d34-0410-b5e6-96231b3b80d8
After uses of a live range are removed, recompute the live range to only cover
the remaining uses. This is necessary after rematerializing the value before
some (but not all) uses.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125058 91177308-0d34-0410-b5e6-96231b3b80d8
A live range cannot be split everywhere in a basic block. A split must go before
the first terminator, and if the variable is live into a landing pad, the split
must happen before the call that can throw.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124894 91177308-0d34-0410-b5e6-96231b3b80d8
benchmarks hitting an assertion.
Adds LiveIntervalUnion::collectInterferingVRegs.
Fixes "late spilling" by checking for any unspillable live vregs among
all physReg aliases.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118701 91177308-0d34-0410-b5e6-96231b3b80d8
must be called in the pass's constructor. This function uses static dependency declarations to recursively initialize
the pass's dependencies.
Clients that only create passes through the createFooPass() APIs will require no changes. Clients that want to use the
CommandLine options for passes will need to manually call the appropriate initialization functions in PassInitialization.h
before parsing commandline arguments.
I have tested this with all standard configurations of clang and llvm-gcc on Darwin. It is possible that there are problems
with the static dependencies that will only be visible with non-standard options. If you encounter any crash in pass
registration/creation, please send the testcase to me directly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116820 91177308-0d34-0410-b5e6-96231b3b80d8
register at a time. This turns out to be slightly faster than iterating over
instructions, but more importantly, it allows us to compute spill weights for
new registers created after the spill weight pass has run.
Also compute the allocation hint at the same time as the spill weight. This
allows us to use the spill weight as a cost metric for copies, and choose the
most profitable hint if there is more than one possibility.
The new hints provide a very small (< 0.1%) but universal code size improvement.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110631 91177308-0d34-0410-b5e6-96231b3b80d8
