tracksSubRegLiveness only depends on the Subtarget and a cl::opt, there
is not need to change it or save/parse it in a .mir file.
Make the field const and move the initialization LiveIntervalAnalysis to the
MachineRegisterInfo constructor. Also cleanup some code and fix some
instances which better use MachineRegisterInfo::subRegLivenessEnabled() instead
of TargetSubtargetInfo::enableSubRegLiveness().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@279676 91177308-0d34-0410-b5e6-96231b3b80d8
The register allocator can split a live interval of a register into a set
of smaller intervals. After the allocation of registers is complete, the
rewriter will modify the IR to replace virtual registers with the corres-
ponding physical registers. At this stage, if a register corresponding
to a subregister of a virtual register is used, the rewriter will check
if that subregister is undefined, and if so, it will add the <undef> flag
to the machine operand. The function verifying liveness of the subregis-
ter would assume that it is undefined, unless any of the subranges of the
live interval proves otherwise.
The problem is that the live intervals created during splitting do not
have any subranges, even if the original parent interval did. This could
result in the <undef> flag placed on a register that is actually defined.
Differential Revision: http://reviews.llvm.org/D21189
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@279625 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
See the new test case for one that was (non-deterministically) crashing
on trunk and deterministically hit the assertion that I added in D23302.
Basically, the machine function contains a sequence
DS_WRITE_B32 %vreg4, %vreg14:sub0, ...
DS_WRITE_B32 %vreg4, %vreg14:sub0, ...
%vreg14:sub1<def> = COPY %vreg14:sub0
and SILoadStoreOptimizer::mergeWrite2Pair merges the two DS_WRITE_B32
instructions into one before calling repairIntervalsInRange.
Now repairIntervalsInRange wants to repair %vreg14, in particular, and
ends up trying to repair %vreg14:sub1 as well, but that only becomes
active _after_ the range that is to be repaired, hence the crash due
to LR.find(...) == LR.begin() at the start of repairOldRegInRange.
I believe that just skipping those subrange is fine, but again, not too
familiar with that code.
Reviewers: MatzeB, kparzysz, tstellarAMD
Subscribers: llvm-commits, MatzeB
Differential Revision: https://reviews.llvm.org/D23303
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@278268 91177308-0d34-0410-b5e6-96231b3b80d8
If we move a last-use register read to a later position we may skip
intermediate segments. This may require us to not only extend the
segment before the NewIdx, but also extend the segment live-in to
OldIdx.
This switches LiveIntervalTest to use AMDGPU so we can test subregister
liveness.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@276724 91177308-0d34-0410-b5e6-96231b3b80d8
undef uses are no real uses of a register and must be ignored by
findLastUseBefore() so that handleMove() does not produce invalid live
intervals in some cases.
This fixed http://llvm.org/PR28083
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@272446 91177308-0d34-0410-b5e6-96231b3b80d8
Refactor LiveIntervals::renameDisconnectedComponents() to be a pass.
Also change the name to "RenameIndependentSubregs":
- renameDisconnectedComponents() worked on a MachineFunction at a time
so it is a natural candidate for a machine function pass.
- The algorithm is testable with a .mir test now.
- This also fixes a problem where the lazy renaming as part of the
MachineScheduler introduced IMPLICIT_DEF instructions after the number
of a nodes in a region were counted leading to a mismatch.
Differential Revision: http://reviews.llvm.org/D20507
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@271345 91177308-0d34-0410-b5e6-96231b3b80d8
This fixes a bug introduced in:
r262115 - CodeGen: Take MachineInstr& in SlotIndexes and LiveIntervals, NFC
The iterator End here might == MBB->end(), and so we can't unconditionally
dereference it. This often goes unnoticed (I don't have a test case that always
crashes, and ASAN does not catch it either) because the function call arguments are
turned right back into iterators. MachineInstrBundleIterator's constructor,
however, does have an assert which might randomly fire.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@270323 91177308-0d34-0410-b5e6-96231b3b80d8
We now use LiveRangeCalc::extendToUses() instead of a specially designed
algorithm in constructMainRangeFromSubranges():
- The original motivation for constructMainRangeFromSubranges() were
differences between the main liverange and subranges because of hidden
dead definitions. This case however cannot happen anymore with the
DetectDeadLaneMasks pass in place.
- It simplifies the code.
- This fixes a longstanding bug where we did not properly create new SSA
values on merging control flow (the MachineVerifier missed most of
these cases).
- Move constructMainRangeFromSubranges() to LiveIntervalAnalysis and
LiveRangeCalc to better match the implementation/available helper
functions.
This re-applies r269016. The fixes from r270290 and r270259 should avoid
the machine verifier problems this time.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@270291 91177308-0d34-0410-b5e6-96231b3b80d8
Fix renameDisconnectedComponents() creating vreg uses that can be
reached from function begin withouthaving a definition (or explicit
live-in). Fix this by inserting IMPLICIT_DEF instruction before
control-flow joins as necessary.
Removes an assert from MachineScheduler because we may now get
additional IMPLICIT_DEF when preparing the scheduling policy.
This fixes the underlying problem of http://llvm.org/PR27705
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@270259 91177308-0d34-0410-b5e6-96231b3b80d8
We now use LiveRangeCalc::extendToUses() instead of a specially designed
algorithm in constructMainRangeFromSubranges():
- The original motivation for constructMainRangeFromSubranges() were
differences between the main liverange and subranges because of hidden
dead definitions. This case however cannot happen anymore with the
DetectDeadLaneMasks pass in place.
- It simplifies the code.
- This fixes a longstanding bug where we did not properly create new SSA
values on merging control flow (the MachineVerifier missed most of
these cases).
- Move constructMainRangeFromSubranges() to LiveIntervalAnalysis and
LiveRangeCalc to better match the implementation/available helper
functions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@269016 91177308-0d34-0410-b5e6-96231b3b80d8
Fix handleMove() incorrectly extending liveranges when an undef input of
a vreg was moved past the (current) end of the liverange.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@268805 91177308-0d34-0410-b5e6-96231b3b80d8
This requirement was a huge hack to keep LiveVariables alive because it
was optionally used by TwoAddressInstructionPass and PHIElimination.
However we have AnalysisUsage::addUsedIfAvailable() which we can use in
those passes.
This re-applies r260806 with LiveVariables manually added to PowerPC to
hopefully not break the stage 2 bots this time.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@267954 91177308-0d34-0410-b5e6-96231b3b80d8
The DetectDeadLaneMask already ensures that we have no dead subregister
definitions making the special handling in LiveIntervalAnalysis
unnecessary. This reverts most of r248335.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@267937 91177308-0d34-0410-b5e6-96231b3b80d8
handleMove() was incorrectly swapping two value numbers. This was missed
before because the problem only occured when moving subregister definitions
and needed -verify-machineinstrs to be detected.
I cannot add a testcase as long as I cannot reapply r260905/r260806.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@267840 91177308-0d34-0410-b5e6-96231b3b80d8
Update APIs in MachineInstrBundle.h to take and return MachineInstr&
instead of MachineInstr* when the instruction cannot be null. Besides
being a nice cleanup, this is tacking toward a fix for PR26753.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@262141 91177308-0d34-0410-b5e6-96231b3b80d8
Take MachineInstr by reference instead of by pointer in SlotIndexes and
the SlotIndex wrappers in LiveIntervals. The MachineInstrs here are
never null, so this cleans up the API a bit. It also incidentally
removes a few implicit conversions from MachineInstrBundleIterator to
MachineInstr* (see PR26753).
At a couple of call sites it was convenient to convert to a range-based
for loop over MachineBasicBlock::instr_begin/instr_end, so I added
MachineBasicBlock::instrs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@262115 91177308-0d34-0410-b5e6-96231b3b80d8
MBB slot index intervals are half open, not closed. getMBBEndIndex()
returns the slot index of the start of the next block in layout order.
Placing a register mask there is incorrect if the successor of the
funclet return is not laid out after the return. Clang generates IR for
catch bodies before generating the following normal code, so we never
noticed this issue until the D frontend authors filed a bug about it.
Instead, we can put the clobber mask on the last instruction of the
funclet return block. We still aren't using a register mask operand on
the CATCHRET instruction because it would cause PEI to spill all CSRs,
including XMM regs, in the prologue.
Fixes PR26679.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@262035 91177308-0d34-0410-b5e6-96231b3b80d8
The commit breaks stage2 compilation on PowerPC. Reverting for now while
this is analyzed. I also have to revert the LiveIntervalTest for now as
that depends on this commit.
Revert "LiveIntervalAnalysis: Remove LiveVariables requirement"
This reverts commit r260806.
Revert "Remove an unnecessary std::move to fix -Wpessimizing-move warning."
This reverts commit r260931.
Revert "Fix typo in LiveIntervalTest"
This reverts commit r260907.
Revert "Add unittest for LiveIntervalAnalysis::handleMove()"
This reverts commit r260905.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@261189 91177308-0d34-0410-b5e6-96231b3b80d8
This is an updated version which fixes a bug that happened with
uses tied to an earlyclobber operand which end at an unusual slotindex.
If two definitions write to independent subregisters then they can be
put in any order. LiveIntervalAnalysis::handleMove() did not support
this previously because it looks like moving a definition of a vreg past
another one.
This is a modified version of a patch proposed (two years ago) by
Vincent Lejeune! This version does not touch the read-undef flags and is
extended for the case of moving a subregister def behind all uses - this
can happen for subregister defs that are completely unused.
Differential Revision: http://reviews.llvm.org/D9067
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260906 91177308-0d34-0410-b5e6-96231b3b80d8
This requirement was a huge hack to keep LiveVariables alive because it
was optionally used by TwoAddressInstructionPass and PHIElimination.
However we have AnalysisUsage::addUsedIfAvailable() which we can use in
those passes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260806 91177308-0d34-0410-b5e6-96231b3b80d8
Matthias Braun
Krzysztof Parzyszek
Nicolai Haehnle
Hal Finkel
Tom Stellard
Mehdi Amini
Duncan P. N. Exon Smith
Reid Kleckner