Summary:
If we have a MI marked with bitcast bits, but without input operands,
PeepholeOptimizer might crash with assert.
eg:
If we apply the changes in PPCInstrVSX.td as in this patch:
[(set v4i32:$XT, (bitconvert (v16i8 immAllOnesV)))]>;
We will get assert in PeepholeOptimizer.
```
llvm-lit llvm-project/llvm/test/CodeGen/PowerPC/build-vector-tests.ll -v
llvm-project/llvm/include/llvm/CodeGen/MachineInstr.h:417: const
llvm::MachineOperand &llvm::MachineInstr::getOperand(unsigned int)
const: Assertion `i < getNumOperands() && "getOperand() out of range!"'
failed.
```
The fix is to abort if we found out of bound access.
Reviewers: qcolombet, MatzeB, hfinkel, arsenm
Reviewed By: qcolombet
Subscribers: wdng, arsenm, steven.zhang, wuzish, nemanjai, hiraditya, kbarton, MaskRay, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D65542
llvm-svn: 369261
Summary:
This clang-tidy check is looking for unsigned integer variables whose initializer
starts with an implicit cast from llvm::Register and changes the type of the
variable to llvm::Register (dropping the llvm:: where possible).
Partial reverts in:
X86FrameLowering.cpp - Some functions return unsigned and arguably should be MCRegister
X86FixupLEAs.cpp - Some functions return unsigned and arguably should be MCRegister
X86FrameLowering.cpp - Some functions return unsigned and arguably should be MCRegister
HexagonBitSimplify.cpp - Function takes BitTracker::RegisterRef which appears to be unsigned&
MachineVerifier.cpp - Ambiguous operator==() given MCRegister and const Register
PPCFastISel.cpp - No Register::operator-=()
PeepholeOptimizer.cpp - TargetInstrInfo::optimizeLoadInstr() takes an unsigned&
MachineTraceMetrics.cpp - MachineTraceMetrics lacks a suitable constructor
Manual fixups in:
ARMFastISel.cpp - ARMEmitLoad() now takes a Register& instead of unsigned&
HexagonSplitDouble.cpp - Ternary operator was ambiguous between unsigned/Register
HexagonConstExtenders.cpp - Has a local class named Register, used llvm::Register instead of Register.
PPCFastISel.cpp - PPCEmitLoad() now takes a Register& instead of unsigned&
Depends on D65919
Reviewers: arsenm, bogner, craig.topper, RKSimon
Reviewed By: arsenm
Subscribers: RKSimon, craig.topper, lenary, aemerson, wuzish, jholewinski, MatzeB, qcolombet, dschuff, jyknight, dylanmckay, sdardis, nemanjai, jvesely, wdng, nhaehnle, sbc100, jgravelle-google, kristof.beyls, hiraditya, aheejin, kbarton, fedor.sergeev, javed.absar, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, tpr, PkmX, jocewei, jsji, Petar.Avramovic, asbirlea, Jim, s.egerton, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D65962
llvm-svn: 369041
Handle call instruction replacements and deletions in order to preserve
valid state of the call site info of the MachineFunction.
NOTE: If the call site info is enabled for a new target, the assertion from
the MachineFunction::DeleteMachineInstr() should help to locate places
where the updateCallSiteInfo() should be called in order to preserve valid
state of the call site info.
([10/13] Introduce the debug entry values.)
Co-authored-by: Ananth Sowda <asowda@cisco.com>
Co-authored-by: Nikola Prica <nikola.prica@rt-rk.com>
Co-authored-by: Ivan Baev <ibaev@cisco.com>
Differential Revision: https://reviews.llvm.org/D61062
llvm-svn: 364536
Peephole opt has a one use limitation which appears to be accidental. The function being used was incorrectly documented as returning whether the def had one *user*, but instead returned true only when there was one *use*. Add a corresponding hasOneNonDbgUser helper, and adjust peephole-opt to use the appropriate one.
All of the actual folding code handles multiple uses within a single instruction. That codepath is well exercised through instruction selection.
Differential Revision: https://reviews.llvm.org/D63656
llvm-svn: 364336
The ISD::STRICT_ nodes used to implement the constrained floating-point
intrinsics are currently never passed to the target back-end, which makes
it impossible to handle them correctly (e.g. mark instructions are depending
on a floating-point status and control register, or mark instructions as
possibly trapping).
This patch allows the target to use setOperationAction to switch the action
on ISD::STRICT_ nodes to Legal. If this is done, the SelectionDAG common code
will stop converting the STRICT nodes to regular floating-point nodes, but
instead pass the STRICT nodes to the target using normal SelectionDAG
matching rules.
To avoid having the back-end duplicate all the floating-point instruction
patterns to handle both strict and non-strict variants, we make the MI
codegen explicitly aware of the floating-point exceptions by introducing
two new concepts:
- A new MCID flag "mayRaiseFPException" that the target should set on any
instruction that possibly can raise FP exception according to the
architecture definition.
- A new MI flag FPExcept that CodeGen/SelectionDAG will set on any MI
instruction resulting from expansion of any constrained FP intrinsic.
Any MI instruction that is *both* marked as mayRaiseFPException *and*
FPExcept then needs to be considered as raising exceptions by MI-level
codegen (e.g. scheduling).
Setting those two new flags is straightforward. The mayRaiseFPException
flag is simply set via TableGen by marking all relevant instruction
patterns in the .td files.
The FPExcept flag is set in SDNodeFlags when creating the STRICT_ nodes
in the SelectionDAG, and gets inherited in the MachineSDNode nodes created
from it during instruction selection. The flag is then transfered to an
MIFlag when creating the MI from the MachineSDNode. This is handled just
like fast-math flags like no-nans are handled today.
This patch includes both common code changes required to implement the
new features, and the SystemZ implementation.
Reviewed By: andrew.w.kaylor
Differential Revision: https://reviews.llvm.org/D55506
llvm-svn: 362663
This patch removes an overly conservative check that would prevent
simplifying copies when the value we were tracking would go through
several subregister indices.
Indeed, the intend of this check was to not track values whenever
we have to compose subregister, but actually what the check was
doing was bailing anytime we see a second subreg, even if that
second subreg would actually be the new source of truth (as opposed
to a part of that subreg).
Differential Revision: https://reviews.llvm.org/D59891
llvm-svn: 357095
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
The DEBUG() macro is very generic so it might clash with other projects.
The renaming was done as follows:
- git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g'
- git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM
- Manual change to APInt
- Manually chage DOCS as regex doesn't match it.
In the transition period the DEBUG() macro is still present and aliased
to the LLVM_DEBUG() one.
Differential Revision: https://reviews.llvm.org/D43624
llvm-svn: 332240
Because we create a new kind of debug instruction, DBG_LABEL, we need to
check all passes which use isDebugValue() to check MachineInstr is debug
instruction or not. When expelling debug instructions, we should expel
both DBG_VALUE and DBG_LABEL. So, I create a new function,
isDebugInstr(), in MachineInstr to check whether the MachineInstr is
debug instruction or not.
This patch has no new test case. I have run regression test and there is
no difference in regression test.
Differential Revision: https://reviews.llvm.org/D45342
Patch by Hsiangkai Wang.
llvm-svn: 331844
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.
Patch produced by
for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done
Differential Revision: https://reviews.llvm.org/D46290
llvm-svn: 331272
- Less unnecessary use of `auto`
- Add early `using RegSubRegPair(AndIdx) =` to avoid countless
`TargetInstrInfo::` qualifications.
- Use references instead of pointers where possible.
- Remove unused parameters.
- Rewrite the CopyRewriter class hierarchy:
- Pull out uncoalescable copy rewriting functionality into
PeepholeOptimizer class.
- Use an abstract base class to make it clear that rewriters are
independent.
- Remove unnecessary \brief in doxygen comments.
- Remove unused constructor and method from ValueTracker.
- Replace UseAdvancedTracking of ValueTracker with DisableAdvCopyOpt use.
llvm-svn: 322325
The PeepholeOptimizer would fail for vregs without a definition. If this
was caused by an undef operand abort to keep the code simple (so we
don't need to add logic everywhere to replicate the undef flag).
Differential Revision: https://reviews.llvm.org/D40763
llvm-svn: 322319
When replacing a PHI the PeepholeOptimizer currently takes the register
class of the register at the first operand. This however is not correct
if this argument has a subregister index.
As there is currently no API to query the register class resulting from
applying a subregister index to all registers in a class, we can only
abort in these cases and not perform the transformation.
This changes findNextSource() to require the end of all copy chains to
not use a subregister if there is any PHI in the chain. I had to rewrite
the overly complicated inner loop there to have a good place to insert
the new check.
This fixes https://llvm.org/PR33071 (aka rdar://32262041)
Differential Revision: https://reviews.llvm.org/D40758
llvm-svn: 322313
As part of the unification of the debug format and the MIR format, avoid
printing "vreg" for virtual registers (which is one of the current MIR
possibilities).
Basically:
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E "s/%vreg([0-9]+)/%\1/g"
* grep -nr '%vreg' . and fix if needed
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E "s/ vreg([0-9]+)/ %\1/g"
* grep -nr 'vreg[0-9]\+' . and fix if needed
Differential Revision: https://reviews.llvm.org/D40420
llvm-svn: 319427
As part of the unification of the debug format and the MIR format,
always print registers as lowercase.
* Only debug printing is affected. It now follows MIR.
Differential Revision: https://reviews.llvm.org/D40417
llvm-svn: 319187
All these headers already depend on CodeGen headers so moving them into
CodeGen fixes the layering (since CodeGen depends on Target, not the
other way around).
llvm-svn: 318490
This header includes CodeGen headers, and is not, itself, included by
any Target headers, so move it into CodeGen to match the layering of its
implementation.
llvm-svn: 317647
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
While we can usually replace bitcast like instructions
(MachineInstr::isBitcast()) with a COPY this is not legal if any of the
users uses SUBREG_TO_REG to assert the upper bits of the result are
zero.
Differential Revision: https://reviews.llvm.org/D28474
llvm-svn: 291483
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
llvm-svn: 289820
The general idea here is to get enough of the existing restrictions out of the way that the already existing folding logic in foldMemoryOperand can kick in for STATEPOINTs and fold references to immutable stack slots. The key changes are:
Support for folding multiple operands at once which reference the same load
Support for folding multiple loads into a single instruction
Walk all the operands of the instruction for varidic instructions (this is a bug fix!)
Once this lands, I'll post another patch which refactors the TII interface here. There's nothing actually x86 specific about the x86 code used here.
Differential Revision: https://reviews.llvm.org/D24103
llvm-svn: 289510
This is mostly a mechanical change to make TargetInstrInfo API take
MachineInstr& (instead of MachineInstr* or MachineBasicBlock::iterator)
when the argument is expected to be a valid MachineInstr. This is a
general API improvement.
Although it would be possible to do this one function at a time, that
would demand a quadratic amount of churn since many of these functions
call each other. Instead I've done everything as a block and just
updated what was necessary.
This is mostly mechanical fixes: adding and removing `*` and `&`
operators. The only non-mechanical change is to split
ARMBaseInstrInfo::getOperandLatencyImpl out from
ARMBaseInstrInfo::getOperandLatency. Previously, the latter took a
`MachineInstr*` which it updated to the instruction bundle leader; now,
the latter calls the former either with the same `MachineInstr&` or the
bundle leader.
As a side effect, this removes a bunch of MachineInstr* to
MachineBasicBlock::iterator implicit conversions, a necessary step
toward fixing PR26753.
Note: I updated WebAssembly, Lanai, and AVR (despite being
off-by-default) since it turned out to be easy. I couldn't run tests
for AVR since llc doesn't link with it turned on.
llvm-svn: 274189
The original commit was reverted because of a buildbot problem with LazyCallGraph::SCC handling (not related to the OptBisect handling).
Differential Revision: http://reviews.llvm.org/D19172
llvm-svn: 267231
This patch implements a optimization bisect feature, which will allow optimizations to be selectively disabled at compile time in order to track down test failures that are caused by incorrect optimizations.
The bisection is enabled using a new command line option (-opt-bisect-limit). Individual passes that may be skipped call the OptBisect object (via an LLVMContext) to see if they should be skipped based on the bisect limit. A finer level of control (disabling individual transformations) can be managed through an addition OptBisect method, but this is not yet used.
The skip checking in this implementation is based on (and replaces) the skipOptnoneFunction check. Where that check was being called, a new call has been inserted in its place which checks the bisect limit and the optnone attribute. A new function call has been added for module and SCC passes that behaves in a similar way.
Differential Revision: http://reviews.llvm.org/D19172
llvm-svn: 267022
Target-specific instructions may have uninteresting physreg clobbers,
for target-specific reasons. The peephole pass doesn't need to concern
itself with such defs, as long as they're implicit and marked as dead.
llvm-svn: 255182
Code generation often exposes redundant physical register copies through
virtual registers such as:
%vreg = COPY %PHYSREG
...
%PHYSREG = COPY %vreg
There are cases where no intervening clobber of %PHYSREG occurs, and the
later copy could therefore be removed. In some cases this further allows
us to remove the initial copy.
This patch contains a motivating example which comes from the x86 build
of Chrome, specifically cc::ResourceProvider::UnlockForRead uses
libstdc++'s implementation of hash_map. That example has two tests live
at the same time, and after machine sinking LLVM has confused itself
enough and things spilling EFLAGS is a great idea even though it's
never restored and the comparison results are both live.
Before this patch we have:
DEC32m %RIP, 1, %noreg, <ga:@L>, %noreg, %EFLAGS<imp-def>
%vreg1<def> = COPY %EFLAGS; GR64:%vreg1
%EFLAGS<def> = COPY %vreg1; GR64:%vreg1
JNE_1 <BB#1>, %EFLAGS<imp-use>
Both copies are useless. This patch tries to eliminate the later copy in
a generic manner.
dec is especially confusing to LLVM when compared with sub.
I wrote this patch to treat all physical registers generically, but only
remove redundant copies of non-allocatable physical registers because
the allocatable ones caused issues (e.g. when calling conventions weren't
properly modeled) and should be handled later by the register allocator
anyways.
The following tests used to failed when the patch also replaced allocatable
registers:
CodeGen/X86/StackColoring.ll
CodeGen/X86/avx512-calling-conv.ll
CodeGen/X86/copy-propagation.ll
CodeGen/X86/inline-asm-fpstack.ll
CodeGen/X86/musttail-varargs.ll
CodeGen/X86/pop-stack-cleanup.ll
CodeGen/X86/preserve_mostcc64.ll
CodeGen/X86/tailcallstack64.ll
CodeGen/X86/this-return-64.ll
This happens because COPY has other special meaning for e.g. dependency
breakage and x87 FP stack.
Note that all other backends' tests pass.
Reviewers: qcolombet
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D15157
llvm-svn: 254665
If a virtual register is copied and another copy was already
seen, replace with the previous copy. This only handles the
simplest cases for now.
This pattern shows up from various operand restrictions
AMDGPU has which require inserting copies depending
on the register class of the operands.
llvm-svn: 248611
Allow a target to do something other than search for copies
that will avoid cross register bank copies.
Implement for SI by only rewriting the most basic copies,
so it should look through anything like a subregister extract.
I'm not entirely satisified with this because it seems like
eliminating a reg_sequence that isn't fully used should work
generically for all targets without them having to override
something. However, it seems to be tricky to have a simple
implementation of this without rewriting to invalid kinds
of subregister copies on some targets.
I'm not sure if there is currently a generic way to easily check
if a subregister index would be valid for the current use.
The current set of TargetRegisterInfo::get*Class functions don't
quite behave like I would expect (e.g. getSubClassWithSubReg
returns the maximal register class rather than the minimal), so
I'm not sure how to make the generic test keep searching if
SrcRC:SrcSubReg is a valid replacement for DefRC:DefSubReg. Making
the default implementation to check for simple copies breaks
a variety of ARM and x86 tests by producing illegal subregister uses.
The ARM tests are not actually changed since it should still be using
the same sharesSameRegisterFile implementation, this just relaxes
them to not check for specific registers.
llvm-svn: 248478
Reintroduce r245442. Remove an overly conservative assertion introduced
in r245442. We could replace the assertion to use `shareSameRegisterFile`
instead, but in that point in `insertPHI` we already lost the original
Def subreg to check against. So drop the assertion completely.
Original commit message:
- Teaches the ValueTracker in the PeepholeOptimizer to look through PHI
instructions.
- Add findNextSourceAndRewritePHI method to lookup into multiple sources
returnted by the ValueTracker and rewrite PHIs with new sources.
With these changes we can find more register sources and rewrite more
copies to allow coaslescing of bitcast instructions. Hence, we eliminate
unnecessary VR64 <-> GR64 copies in x86, but it could be extended to
other archs by marking "isBitcast" on target specific instructions. The
x86 example follows:
A:
psllq %mm1, %mm0
movd %mm0, %r9
jmp C
B:
por %mm1, %mm0
movd %mm0, %r9
jmp C
C:
movd %r9, %mm0
pshufw $238, %mm0, %mm0
Becomes:
A:
psllq %mm1, %mm0
jmp C
B:
por %mm1, %mm0
jmp C
C:
pshufw $238, %mm0, %mm0
Differential Revision: http://reviews.llvm.org/D11197
rdar://problem/20404526
llvm-svn: 245479
Reapply r243486.
- Teaches the ValueTracker in the PeepholeOptimizer to look through PHI
instructions.
- Add findNextSourceAndRewritePHI method to lookup into multiple sources
returnted by the ValueTracker and rewrite PHIs with new sources.
With these changes we can find more register sources and rewrite more
copies to allow coaslescing of bitcast instructions. Hence, we eliminate
unnecessary VR64 <-> GR64 copies in x86, but it could be extended to
other archs by marking "isBitcast" on target specific instructions. The
x86 example follows:
A:
psllq %mm1, %mm0
movd %mm0, %r9
jmp C
B:
por %mm1, %mm0
movd %mm0, %r9
jmp C
C:
movd %r9, %mm0
pshufw $238, %mm0, %mm0
Becomes:
A:
psllq %mm1, %mm0
jmp C
B:
por %mm1, %mm0
jmp C
C:
pshufw $238, %mm0, %mm0
Differential Revision: http://reviews.llvm.org/D11197
rdar://problem/20404526
llvm-svn: 245442
This abstracts away the test for "when can we fold across a MachineInstruction"
into the the MI interface, and changes call-frame optimization use the same test
the peephole optimizer users.
Differential Revision: http://reviews.llvm.org/D11945
llvm-svn: 244729
The condition for clearing the folding candidate list was clamped together
with the "uninteresting instruction" condition. This is too conservative,
e.g. we don't need to clear the list when encountering an IMPLICIT_DEF.
Differential Revision: http://reviews.llvm.org/D11591
llvm-svn: 244577
Alexander Timofeev