Add new predicate to more accurately model the cost of arithmetic and
logical operations shifted left.
Differential revision: https://reviews.llvm.org/D37151
llvm-svn: 311943
Instead of loading 0 from a constant pool, it's of course much better to
materialize it using an fmov and the zero register.
Thanks to Ahmed Bougacha for the suggestion.
Differential Revision: https://reviews.llvm.org/D37102
llvm-svn: 311662
Before, the outliner would mark all instructions that read from/modify LR as
illegal. This doesn't handle W30, which overlaps with LR. This shouldn't be
outlined.
This commit fixes that by making modifiesRegister() and readsRegister() look at
W30 + take in a TRI argument. This makes sure that modifiesRegister() and
readsRegister() won't outline either of W30 and LR.
https://reviews.llvm.org/D36435
llvm-svn: 310422
This commit
- Removes IsTailCall and replaces it with a target-defined unsigned
- Refactors getOutliningCallOverhead and getOutliningFrameOverhead so that they don't use IsTailCall
- Adds a call class + frame class classification to OutlinedFunction and Candidate respectively
This accomplishes a couple things.
Firstly, we don't need the notion of *tail call* in the general outlining algorithm.
Secondly, we now can have different "outlining classes" for each candidate within a set of candidates.
This will make it easy to add new ways to outline sequences for certain targets and dynamically choose
an appropriate cost model for a sequence depending on the context that that sequence lives in.
Ultimately, this should get us closer to being able to do something like, say avoid saving the link
register when outlining AArch64 instructions.
llvm-svn: 309475
This is some more cleanup in preparation for some actual
functional changes. This splits getOutliningBenefit into
two cost functions: getOutliningCallOverhead and
getOutliningFrameOverhead. These functions return the
number of instructions that would be required to call
a specific function and the number of instructions
that would be required to construct a frame for a
specific funtion. The actual outlining benefit logic
is moved into the outliner, which calls these functions.
The goal of refactoring getOutliningBenefit is to:
- Get us closer to getting rid of the IsTailCall flag
- Further split up "target-specific" things and
"general algorithm" things
llvm-svn: 309356
Summary:
This patch is the first step in reducing HW prefetcher instruction tag
collisions in inner loops for Falkor. It adds a pass that annotates IR
loads with metadata to indicate that they are known to be strided loads,
and adds a target lowering hook that translates this metadata to a
target-specific MachineMemOperand flag.
A follow on change will use this MachineMemOperand flag to re-write
instructions to reduce tag collisions.
Reviewers: mcrosier, t.p.northover
Subscribers: aemerson, rengolin, mgorny, javed.absar, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D34963
llvm-svn: 308059
Summary: Add target hooks for printing and parsing target MMO flags.
Targets may override getSerializableMachineMemOperandTargetFlags() to
return a mapping from string to flag value for target MMO values that
should be serialized/parsed in MIR output.
Add implementation of this hook for AArch64 SuppressPair MMO flag.
Reviewers: bogner, hfinkel, qcolombet, MatzeB
Subscribers: mcrosier, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D34962
llvm-svn: 307877
This patch contains a pass that transforms CBZ/CBNZ/TBZ/TBNZ instructions into a
conditional branch (Bcc), when the NZCV flags can be set for "free". This is
preferred on targets that have more flexibility when scheduling Bcc
instructions as compared to CBZ/CBNZ/TBZ/TBNZ (assuming all other variables are
equal). This can reduce register pressure and is also the default behavior for
GCC.
A few examples:
add w8, w0, w1 -> cmn w0, w1 ; CMN is an alias of ADDS.
cbz w8, .LBB_2 -> b.eq .LBB0_2 ; single def/use of w8 removed.
add w8, w0, w1 -> adds w8, w0, w1 ; w8 has multiple uses.
cbz w8, .LBB1_2 -> b.eq .LBB1_2
sub w8, w0, w1 -> subs w8, w0, w1 ; w8 has multiple uses.
tbz w8, #31, .LBB6_2 -> b.ge .LBB6_2
In looking at all current sub-target machine descriptions, this transformation
appears to be either positive or neutral.
Differential Revision: https://reviews.llvm.org/D34220.
llvm-svn: 306144
I did this a long time ago with a janky python script, but now
clang-format has built-in support for this. I fed clang-format every
line with a #include and let it re-sort things according to the precise
LLVM rules for include ordering baked into clang-format these days.
I've reverted a number of files where the results of sorting includes
isn't healthy. Either places where we have legacy code relying on
particular include ordering (where possible, I'll fix these separately)
or where we have particular formatting around #include lines that
I didn't want to disturb in this patch.
This patch is *entirely* mechanical. If you get merge conflicts or
anything, just ignore the changes in this patch and run clang-format
over your #include lines in the files.
Sorry for any noise here, but it is important to keep these things
stable. I was seeing an increasing number of patches with irrelevant
re-ordering of #include lines because clang-format was used. This patch
at least isolates that churn, makes it easy to skip when resolving
conflicts, and gets us to a clean baseline (again).
llvm-svn: 304787
1. RegisterClass::getSize() is split into two functions:
- TargetRegisterInfo::getRegSizeInBits(const TargetRegisterClass &RC) const;
- TargetRegisterInfo::getSpillSize(const TargetRegisterClass &RC) const;
2. RegisterClass::getAlignment() is replaced by:
- TargetRegisterInfo::getSpillAlignment(const TargetRegisterClass &RC) const;
This will allow making those values depend on subtarget features in the
future.
Differential Revision: https://reviews.llvm.org/D31783
llvm-svn: 301221
In addition to the original commit, tighten the condition for when to
pad empty functions to COFF Windows. This avoids running into problems
when targeting e.g. Win32 AMDGPU, which caused test failures when this
was committed initially.
llvm-svn: 301047
Empty functions can lead to duplicate entries in the Guard CF Function
Table of a binary due to multiple functions sharing the same RVA,
causing the kernel to refuse to load that binary.
We had a terrific bug due to this in Chromium.
It turns out we were already doing this for Mach-O in certain
situations. This patch expands the code for that in
AsmPrinter::EmitFunctionBody() and renames
TargetInstrInfo::getNoopForMachoTarget() to simply getNoop() since it
seems it was used for not just Mach-O anyway.
Differential Revision: https://reviews.llvm.org/D32330
llvm-svn: 301040
This concludes the refinements to Falkor Machine Model.
It includes SchedPredicates for immediate zero and LSL Fast.
Forwarding logic is also modeled for vector multiply and
accumulate only.
llvm-svn: 299810
When I tested r298734, I thought that red zones were enabled by default like in
X86. Since red zones are behind a flag on AArch64 the testing wasn't true.
llvm-svn: 298747
AArch64 doesn't require -mno-red-zone; stack fixups are sufficient here. This was
unnecessarily copied over from the X86 target.
(You can now outline with red zones! Yay!)
Removing the requirement passes all Single/MultiSource tests.
llvm-svn: 298734
Forgot to remove some output before committing last time. (Instruction fixups
don't actually overflow anywhere in the test suite so far, so I missed it).
To prevent the outliner from screaming "Overflow!" in the event that that
does happen, this commit removes that output.
llvm-svn: 298260
This commit adds the necessary target hooks for outlining in AArch64. It also
refactors the switch statement used in `getMemOpBaseRegImmOfsWidth` into a
more general function, `getMemOpInfo`. This allows the outliner to share that
code without copying and pasting it.
The AArch64 outliner can be run using -mllvm -enable-machine-outliner, as with
the X86-64 outliner.
The test for this pass verifies that the outliner does, in fact outline
functions, fixes up the stack accesses properly, and can correctly generate a
tail call. In the future, this test should be replaced with a MIR test, so that
we can properly test immediate offset overflows in fixed-up instructions.
llvm-svn: 298162
In fact this default implementation should be the only implementation,
keep it virtual for now to accomodate targets that don't model flags
correctly.
Differential Revision: https://reviews.llvm.org/D30747
llvm-svn: 297980
Summary:
A53 scheduler causes an assertion failure on all CRC instructions:
include/llvm/CodeGen/MachineInstr.h:280: const llvm::MachineOperand
&llvm::MachineInstr::getOperand(unsigned int) const: Assertion `i <
getNumOperands() && "getOperand() out of range!"' failed.
The case statements corresponding to CRC instructions are incorrect and should
be removed.
Also adding a testcase while on this.
Reviewers: t.p.northover, javed.absar, apazos, rengolin
Reviewed By: rengolin
Subscribers: evandro, aemerson, llvm-commits, rengolin
Differential Revision: https://reviews.llvm.org/D30274
llvm-svn: 297582
This patch moves the class for scheduling adjacent instructions,
MacroFusion, to the target.
In AArch64, it also expands the fusion to all instructions pairs in a
scheduling block, beyond just among the predecessors of the branch at the
end.
Differential revision: https://reviews.llvm.org/D28489
llvm-svn: 293737
Summary:
This patch prepares more for tail call support in XRay. Until the logging part supports tail calls, this is just staging, so it seems LLVM part is mostly ready with this patch.
Related: https://reviews.llvm.org/D28948 (compiler-rt)
Reviewers: dberris, rengolin
Reviewed By: dberris
Subscribers: llvm-commits, iid_iunknown, aemerson
Differential Revision: https://reviews.llvm.org/D28947
llvm-svn: 293080
In order to follow the pattern of the existing 'slow-misaligned-128store'
option, rename the option 'no-quad-ldst-pairs' to 'slow-paired-128'.
llvm-svn: 292954
ARM seems to prefer that long literals be formed from their little end in
order to promote the fusion of the instrs pairs MOV/MOVK and MOVK/MOVK on
Cortex A57 and others (v. "Cortex A57 Software Optimisation Guide", section
4.14).
Differential revision: https://reviews.llvm.org/D28697
llvm-svn: 292422
Rename from addOperand to just add, to match the other method that has been
added to MachineInstrBuilder for adding more than just 1 operand.
See https://reviews.llvm.org/D28057 for the whole discussion.
Differential Revision: https://reviews.llvm.org/D28556
llvm-svn: 291891
Summary:
Make AArch64InstrInfo::foldMemoryOperandImpl more general by folding all
full COPYs between register classes of the same size that are either
spilled or refilled.
Reviewers: MatzeB, qcolombet
Subscribers: aemerson, rengolin, mcrosier, llvm-commits
Differential Revision: https://reviews.llvm.org/D27271
llvm-svn: 288439
Summary:
In AArch64InstrInfo::foldMemoryOperandImpl, catch more cases where the
COPY being spilled is copying from WZR/XZR, but the source register is
not in the COPY destination register's regclass.
For example, when spilling:
%vreg0 = COPY %XZR ; %vreg0:GPR64common
without this change, the code in TargetInstrInfo::foldMemoryOperand()
and canFoldCopy() that normally handles cases like this would fail to
optimize since %XZR is not in GPR64common. So the spill code generated
would be:
%vreg0 = COPY %XZR
STR %vreg
instead of the new code generated:
STR %XZR
Reviewers: qcolombet, MatzeB
Subscribers: mcrosier, aemerson, t.p.northover, llvm-commits, rengolin
Differential Revision: https://reviews.llvm.org/D26976
llvm-svn: 288176
This makes the createGenericSchedLive() function that constructs the
default scheduler available for the public API. This should help when
you want to get a scheduler and the default list of DAG mutations.
This also shrinks the list of default DAG mutations:
{Load|Store}ClusterDAGMutation and MacroFusionDAGMutation are no longer
added by default. Targets can easily add them if they need them. It also
makes it easier for targets to add alternative/custom macrofusion or
clustering mutations while staying with the default
createGenericSchedLive(). It also saves the callback back and forth in
TargetInstrInfo::enableClusterLoads()/enableClusterStores().
Differential Revision: https://reviews.llvm.org/D26986
llvm-svn: 288057
AArch64InstrInfo::shouldScheduleAdjacent() determines whether two
instruction can benefit from macroop fusion on apple CPUs. The list
turned out to be incomplete:
- the "rr" variants of the instructions were missing
- even the "rs" variants can have shift value == 0 and behave like the
"rr" variants
This also splits the MacropFusion target feature into
ArithmeticBccFusion and ArithmeticCbzFusion.
Differential Revision: https://reviews.llvm.org/D25142
llvm-svn: 283243
Currently, the machine combiner can proceed matching when -ffast-math is on.
It should also match when only -ffp-contract=fast is specified as was the
case before when DAGCombiner was doing the job.
Patch by: Abderrazek Zaafrani <a.zaafrani@samsung.com>.
Differential Revision: https://reviews.llvm.org/D24366
llvm-svn: 281649
We currently return 4 for stackmaps and patchpoints, which is very optimistic
and can in rare cases cause the branch relaxation pass to fail to relax certain
branches.
This patch causes getInstSizeInBytes to return a pessimistic estimate of the
size as the number of bytes requested in the stackmap/patchpoint. In the future,
we could provide a more accurate estimate by sharing some of the logic in
AArch64::LowerSTACKMAP/PATCHPOINT.
Fixes part of https://llvm.org/bugs/show_bug.cgi?id=28750
Differential Revision: https://reviews.llvm.org/D24073
llvm-svn: 281301
Now that MachineBasicBlock::reverse_instr_iterator knows when it's at
the end (since r281168 and r281170), implement
MachineBasicBlock::reverse_iterator directly on top of an
ilist::reverse_iterator by adding an IsReverse template parameter to
MachineInstrBundleIterator. This replaces another hard-to-reason-about
use of std::reverse_iterator on list iterators, matching the changes for
ilist::reverse_iterator from r280032 (see the "out of scope" section at
the end of that commit message). MachineBasicBlock::reverse_iterator
now has a handle to the current node and has obvious invalidation
semantics.
r280032 has a more detailed explanation of how list-style reverse
iterators (invalidated when the pointed-at node is deleted) are
different from vector-style reverse iterators like std::reverse_iterator
(invalidated on every operation). A great motivating example is this
commit's changes to lib/CodeGen/DeadMachineInstructionElim.cpp.
Note: If your out-of-tree backend deletes instructions while iterating
on a MachineBasicBlock::reverse_iterator or converts between
MachineBasicBlock::iterator and MachineBasicBlock::reverse_iterator,
you'll need to update your code in similar ways to r280032. The
following table might help:
[Old] ==> [New]
delete &*RI, RE = end() delete &*RI++
RI->erase(), RE = end() RI++->erase()
reverse_iterator(I) std::prev(I).getReverse()
reverse_iterator(I) ++I.getReverse()
--reverse_iterator(I) I.getReverse()
reverse_iterator(std::next(I)) I.getReverse()
RI.base() std::prev(RI).getReverse()
RI.base() ++RI.getReverse()
--RI.base() RI.getReverse()
std::next(RI).base() RI.getReverse()
(For more details, have a look at r280032.)
llvm-svn: 281172
Evandro Menezes