Summary:
Some targets need to be able to do more complex rendering than just adding an
operand or two to an instruction. For example, it may need to insert an
instruction to extract a subreg first, or it may need to perform an operation
on the operand.
In SelectionDAG, targets would create SDNode's to achieve the desired effect
during the complex pattern predicate. This worked because SelectionDAG had a
form of garbage collection that would take care of SDNode's that were created
but not used due to a later predicate rejecting a match. This doesn't translate
well to GlobalISel and the churn was wasteful.
The API changes in this patch enable GlobalISel to accomplish the same thing
without the waste. The API is now:
InstructionSelector::OptionalComplexRendererFn selectArithImmed(MachineOperand &Root) const;
where Root is the root of the match. The return value can be omitted to
indicate that the predicate failed to match, or a function with the signature
ComplexRendererFn can be returned. For example:
return OptionalComplexRendererFn(
[=](MachineInstrBuilder &MIB) { MIB.addImm(Immed).addImm(ShVal); });
adds two immediate operands to the rendered instruction. Immed and ShVal are
captured from the predicate function.
As an added bonus, this also reduces the amount of information we need to
provide to GIComplexOperandMatcher.
Depends on D31418
Reviewers: aditya_nandakumar, t.p.northover, qcolombet, rovka, ab, javed.absar
Reviewed By: ab
Subscribers: dberris, kristof.beyls, igorb, llvm-commits
Differential Revision: https://reviews.llvm.org/D31761
llvm-svn: 301079
In dwo files the fixed offset can be used - if the dwos are linked into
a dwp, the dwo consumer must use the dwp tables to find out where the
original range of the debug_info was and resolve the "section relative"
value relative to that original range - effectively
avoiding/reimplementing the relocation handling.
llvm-svn: 301072
Since Split DWARF needs to name the actual .dwo file that is generated,
it can't be known at the time the llvm::Module is produced as it may be
merged with other Modules before the object is generated and that object
may be generated with any name.
By passing the Split DWARF file name when LLVM is producing object code
the .dwo file name in the object file can match correctly.
The support for Split DWARF for implicit modules remains the same -
using metadata to store the dwo name and dwo id so that potentially
multiple skeleton CUs referring to different dwo files can be generated
from one llvm::Module.
llvm-svn: 301062
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
immediate operands.
This commit adds an AArch64 dag-combine that optimizes code generation
for logical instructions taking immediate operands. The optimization
uses demanded bits to change a logical instruction's immediate operand
so that the immediate can be folded into the immediate field of the
instruction.
This recommits r300932 and r300930, which was causing dag-combine to
loop forever. The problem was that optimizeLogicalImm was returning
true even when there was no change to the immediate node (which happened
when the immediate was all zeros or ones), which caused dag-combine to
push and pop the same node to the work list over and over again without
making any progress.
This commit fixes the bug by returning false early in optimizeLogicalImm
if the immediate is all zeros or ones. Also, it changes the code to
compare the immediate with 0 or Mask rather than calling
countPopulation.
rdar://problem/18231627
Differential Revision: https://reviews.llvm.org/D5591
llvm-svn: 301019
It seems that r300930 was creating an infinite loop in dag-combine when
compling the following file:
MultiSource/Benchmarks/MiBench/consumer-typeset/z21.c
llvm-svn: 300940
immediate operands.
This commit adds an AArch64 dag-combine that optimizes code generation
for logical instructions taking immediate operands. The optimization
uses demanded bits to change a logical instruction's immediate operand
so that the immediate can be folded into the immediate field of the
instruction.
This recommits r300913, which broke bots because I didn't fix a call to
ShrinkDemandedConstant in SIISelLowering.cpp after changing the APIs of
TargetLoweringOpt and TargetLowering.
rdar://problem/18231627
Differential Revision: https://reviews.llvm.org/D5591
llvm-svn: 300930
immediate operands.
This commit adds an AArch64 dag-combine that optimizes code generation
for logical instructions taking immediate operands. The optimization
uses demanded bits to change a logical instruction's immediate operand
so that the immediate can be folded into the immediate field of the
instruction.
rdar://problem/18231627
Differential Revision: https://reviews.llvm.org/D5591
llvm-svn: 300913
Associate the version-when-defined with definitions of standard DWARF
constants. Identify the "vendor" for DWARF extensions.
Use this information to verify FORMs in .debug_abbrev are defined as
of the DWARF version specified in the associated unit.
Removed two tests that had specified DWARF v1 (which essentially does
not exist).
Differential Revision: http://reviews.llvm.org/D30785
llvm-svn: 300875
This enables use after free and uninit memory checking for memory
returned by a recycler. SelectionDAG currently relies on the opcode of a
free'd node being ISD::DELETED_NODE, so poke a hole in the asan poison
for SDNode opcodes. This means that we won't find some issues, but only
in SDag.
llvm-svn: 300868
This will become asan errors once the patch lands that poisons the
memory after free. The x86 change is a hack, but I don't see how to
solve this properly at the moment.
llvm-svn: 300867
Recently alloca address space has been added to data layout. Due to this
change, pointer returned by alloca may have different size as pointer in
address space 0.
However, currently the value type of frame index is assumed to be of the
same size as pointer in address space 0.
This patch fixes that.
Most targets assume alloca returning pointer in address space 0, which
is the default alloca address space. Therefore it is NFC for them.
AMDGCN target with amdgiz environment requires this change since it
assumes alloca returning pointer to addr space 5 and its size is 32,
which is different from the size of pointer in addr space 0 which is 64.
Differential Revision: https://reviews.llvm.org/D32021
llvm-svn: 300864
getSignBit is a static function that creates an APInt with only the sign bit set. getSignMask seems like a better name to convey its functionality. In fact several places use it and then store in an APInt named SignMask.
Differential Revision: https://reviews.llvm.org/D32108
llvm-svn: 300856
Adds MVT::ElementCount to represent the length of a
vector which may be scalable, then adds helper functions
that work with it.
Patch by Graham Hunter.
Differential Revision: https://reviews.llvm.org/D32019
llvm-svn: 300842
This patch adds a few helper functions to obtain new vector
value types based on existing ones without needing to care
about whether they are scalable or not.
I've confined their use to a few common locations right now,
and targets that don't have scalable vectors should never
need to care about these.
Patch by Graham Hunter.
Differential Revision: https://reviews.llvm.org/D32017
llvm-svn: 300838
- introduced in r300522 and found via the Swift LLDB testsuite.
The fix is to set the location kind to memory whenever an FrameIndex
location is emitted.
rdar://problem/31707602
llvm-svn: 300793
- introduced in r300522 and found via the Swift LLDB testsuite.
The fix is to set the location kind to memory whenever an FrameIndex
location is emitted.
rdar://problem/31707602
llvm-svn: 300790
I've changed one of the tests to not fold away, but we didn't and still don't do the transform
that the comment claims we do (and I don't know why we'd want to do that).
Follow-up to:
https://reviews.llvm.org/rL300725https://reviews.llvm.org/rL300763
llvm-svn: 300772
This allows forming more 'not' ops, so we get improvements for ISAs that have and-not.
Follow-up to:
https://reviews.llvm.org/rL300725
llvm-svn: 300763
This is preparation for a clang change to improve the [[nodiscard]] warning to not be ignored on methods that return a class marked [[nodiscard]] that are defined in the class itself. See D32207.
We should consider adding wrapper methods to APInt that return the overflow flag directly and discard the APInt result. This would eliminate the void casts and the need to create a bool before the call to pass to the out param.
llvm-svn: 300758
The patch itself is simple: stop discriminating against vectors in visitAnd() and again in
SimplifyDemandedBits().
Some notes for reference:
1. We're not consistent about calls to SimplifyDemandedBits in the various visitXXX functions.
Sometimes, we check if the RHS is a constant first. Other times (like here), we just dive in.
2. I'd like to break the vector shackles in steps for the sake of risk minimization, but we could
make similar simultaneous changes in other places if we think that would be better.
3. I don't know what the intent of the changed tests in this patch was supposed to be, but since
they wiggled in a positive way, I'm just going with that. :)
4. In the rotate tests, note that we can see through non-splat constants. This is a result of D24253.
5. My motivation for being here now is to make D31944 look better, so this is step 1 of N towards
improving the vector codegen in that patch without writing any actual new code.
Differential Revision: https://reviews.llvm.org/D32230
llvm-svn: 300725
This fixes PR32471.
As comment 10 on that bug report highlights
(https://bugs.llvm.org//show_bug.cgi?id=32471#c10), there are quite a
few different defendable design tradeoffs that could be made, including
not representing pointers at all in LLT.
I decided to go for representing vector-of-pointer as a concept in LLT,
while keeping the size of the LLT type 64 bits (this is an increase from
48 bits before). My rationale for keeping pointers explicit is that on
some targets probably it's very handy to have the distinction between
pointer and non-pointer (e.g. 68K has a different register bank for
pointers IIRC). If we keep a scalar pointer, it probably is easiest to
also have a vector-of-pointers to keep LLT relatively conceptually clean
and orthogonal, while we don't have a very strong reason to break that
orthogonality. Once we gain more experience on the use of LLT, we can
of course reconsider this direction.
Rejecting vector-of-pointer types in the IRTranslator is also an option
to avoid the crash reported in PR32471, but that is only a very
short-term solution; also needs quite a bit of code tweaks in places,
and is probably fragile. Therefore I didn't consider this the best
option.
llvm-svn: 300664
This showed up in r300535/r300537, which were reverted in r300538 due to
some of the introduced tests in there failing on some bots, due to the
non-determinism fixed in this commit.
Re-committing r300535/r300537 will add 2 tests for the change in this
commit.
llvm-svn: 300663
Android x86_64 target uses f128 type and stores f128 values in %xmm* registers.
SoftenFloatRes_EXTRACT_VECTOR_ELT should not convert result value
from f128 to i128.
Differential Revision: http://reviews.llvm.org/D32102
llvm-svn: 300583
This patch uses lshrInPlace to replace code where the object that lshr is called on is being overwritten with the result.
This adds an lshrInPlace(const APInt &) version as well.
Differential Revision: https://reviews.llvm.org/D32155
llvm-svn: 300566
Remove non-consecutive stores from store merge candidate search as
they cannot be merged and will prevent us from finding subsequent
mergeable store cases.
Reviewers: jyknight, bogner, javed.absar, spatel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D32086
llvm-svn: 300561
This reverts r300535 and r300537.
The newly added tests in test/CodeGen/AArch64/GlobalISel/arm64-fallback.ll
produces slightly different code between LLVM versions being built with different compilers.
E.g., dependent on the compiler LLVM is built with, either one of the following
can be produced:
remark: <unknown>:0:0: unable to legalize instruction: %vreg0<def>(p0) = G_EXTRACT_VECTOR_ELT %vreg1, %vreg2; (in function: vector_of_pointers_extractelement)
remark: <unknown>:0:0: unable to legalize instruction: %vreg2<def>(p0) = G_EXTRACT_VECTOR_ELT %vreg1, %vreg0; (in function: vector_of_pointers_extractelement)
Non-determinism like this is clearly a bad thing, so reverting this until
I can find and fix the root cause of the non-determinism.
llvm-svn: 300538
This fixes PR32471.
As comment 10 on that bug report highlights
(https://bugs.llvm.org//show_bug.cgi?id=32471#c10), there are quite a
few different defendable design tradeoffs that could be made, including
not representing pointers at all in LLT.
I decided to go for representing vector-of-pointer as a concept in LLT,
while keeping the size of the LLT type 64 bits (this is an increase from
48 bits before). My rationale for keeping pointers explicit is that on
some targets probably it's very handy to have the distinction between
pointer and non-pointer (e.g. 68K has a different register bank for
pointers IIRC). If we keep a scalar pointer, it probably is easiest to
also have a vector-of-pointers to keep LLT relatively conceptually clean
and orthogonal, while we don't have a very strong reason to break that
orthogonality. Once we gain more experience on the use of LLT, we can
of course reconsider this direction.
Rejecting vector-of-pointer types in the IRTranslator is also an option
to avoid the crash reported in PR32471, but that is only a very
short-term solution; also needs quite a bit of code tweaks in places,
and is probably fragile. Therefore I didn't consider this the best
option.
llvm-svn: 300535
The DWARF specification knows 3 kinds of non-empty simple location
descriptions:
1. Register location descriptions
- describe a variable in a register
- consist of only a DW_OP_reg
2. Memory location descriptions
- describe the address of a variable
3. Implicit location descriptions
- describe the value of a variable
- end with DW_OP_stack_value & friends
The existing DwarfExpression code is pretty much ignorant of these
restrictions. This used to not matter because we only emitted very
short expressions that we happened to get right by accident. This
patch makes DwarfExpression aware of the rules defined by the DWARF
standard and now chooses the right kind of location description for
each expression being emitted.
This would have been an NFC commit (for the existing testsuite) if not
for the way that clang describes captured block variables. Based on
how the previous code in LLVM emitted locations, DW_OP_deref
operations that should have come at the end of the expression are put
at its beginning. Fixing this means changing the semantics of
DIExpression, so this patch bumps the version number of DIExpression
and implements a bitcode upgrade.
There are two major changes in this patch:
I had to fix the semantics of dbg.declare for describing function
arguments. After this patch a dbg.declare always takes the *address*
of a variable as the first argument, even if the argument is not an
alloca.
When lowering a DBG_VALUE, the decision of whether to emit a register
location description or a memory location description depends on the
MachineLocation — register machine locations may get promoted to
memory locations based on their DIExpression. (Future) optimization
passes that want to salvage implicit debug location for variables may
do so by appending a DW_OP_stack_value. For example:
DBG_VALUE, [RBP-8] --> DW_OP_fbreg -8
DBG_VALUE, RAX --> DW_OP_reg0 +0
DBG_VALUE, RAX, DIExpression(DW_OP_deref) --> DW_OP_reg0 +0
All testcases that were modified were regenerated from clang. I also
added source-based testcases for each of these to the debuginfo-tests
repository over the last week to make sure that no synchronized bugs
slip in. The debuginfo-tests compile from source and run the debugger.
https://bugs.llvm.org/show_bug.cgi?id=32382
<rdar://problem/31205000>
Differential Revision: https://reviews.llvm.org/D31439
llvm-svn: 300522
The splitIndirectCriticalEdges function generates and invalid CFG when the
'Target' basic block is a loop to itself. When this occurs, the code that
updates the predecessor terminator needs to update the terminator in the split
basic block.
This occurs when there is an edge from block D back to D. Since D is split in
to D0 and D1, the code needs to update the terminator in D1. But D1 is not in
the OtherPreds vector, so it was not getting updated.
Differential Revision: https://reviews.llvm.org/D32126
llvm-svn: 300480
This is a version of D32090 that unifies all of the
`getInstrProf*SectionName` helper functions. (Note: the build failures
which D32090 would have addressed were fixed with r300352.)
We should unify these helper functions because they are hard to use in
their current form. E.g we recently introduced more helpers to fix
section naming for COFF files. This scheme doesn't totally succeed at
hiding low-level details about section naming, so we should switch to an
API that is easier to maintain.
This is not an NFC commit because it fixes llvm-cov's testing support
for COFF files (this falls out of the API change naturally). This is an
area where we lack tests -- I will see about adding one as a follow up.
Testing: check-clang, check-profile, check-llvm.
Differential Revision: https://reviews.llvm.org/D32097
llvm-svn: 300381
This avoids the confusing 'CS.paramHasAttr(ArgNo + 1, Foo)' pattern.
Previously we were testing return value attributes with index 0, so I
introduced hasReturnAttr() for that use case.
llvm-svn: 300367
Instructions CALLSEQ_START..CALLSEQ_END and their target dependent
counterparts keep data like frame size, stack adjustment etc. These
data are accessed by getOperand using hard coded indices. It is
error prone way. This change implements the access by special methods,
which improve readability and allow changing data representation without
massive changes of index values.
Differential Revision: https://reviews.llvm.org/D31953
llvm-svn: 300196
The use of a DenseMap in precomputeTriangleChains does not cause
non-determinism, even though it is iterated over, as the only thing the
iteration does is to insert entries into a new DenseMap, which is not iterated.
Comment only change.
llvm-svn: 300088
The current heuristic is triggered on `InFlightCount > BufferLimit`
which isn't really helpful on in-order cores where BufferLimit is zero.
Note that we already get latency hiding effects for in order cores
by instructions staying in the pending queue on stalls; The additional
latency scheduling heuristics only have minimal effects after that while
occasionally increasing register pressure too much resulting in extra
spills.
My motivation here is additional spills/reloads ending up in a loop in
464.h264ref / BlockMotionSearch function resulting in a 4% overal
regression on an in order core. rdar://30264380
llvm-svn: 300083
and to expose a handle to represent the actual case rather than having
the iterator return a reference to itself.
All of this allows the iterator to be used with common STL facilities,
standard algorithms, etc.
Doing this exposed some missing facilities in the iterator facade that
I've fixed and required some work to the actual iterator to fully
support the necessary API.
Differential Revision: https://reviews.llvm.org/D31548
llvm-svn: 300032
Not clearing was causing non-deterministic compiles for large files. Addresses
for MachineBasicBlocks would end up colliding and we would lay out a block that
we assumed had been pre-computed when it had not been.
llvm-svn: 300022
If you run llc -stop-after=codegenprepare and feed the resulting MIR
to llc -start-after=codegenprepare, you'll have an empty machine
function since we haven't run any isel yet. Of course, this only works
if the MIRParser believes you that this is okay.
This is essentially a revert of r241862 with a fix for the problem it
was papering over.
llvm-svn: 299975
From a user prospective, it forces the use of an annoying nullptr to mark the end of the vararg, and there's not type checking on the arguments.
The variadic template is an obvious solution to both issues.
Differential Revision: https://reviews.llvm.org/D31070
llvm-svn: 299949
Use the same handling in the generic legalizer code as for the other
libcalls (G_FREM, G_FPOW).
Enable it on ARM for float and double so we can test it.
llvm-svn: 299931
Summary: Legalize only if the type is marked as Legal or Custom. If not, return Unsupported as LegalizerHelper is not able to handle non-power-of-2 types right now.
Reviewers: qcolombet, aditya_nandakumar, dsanders, t.p.northover, kristof.beyls, javed.absar, ab
Reviewed By: kristof.beyls, ab
Subscribers: dberris, rovka, igorb, llvm-commits
Differential Revision: https://reviews.llvm.org/D31711
llvm-svn: 299929
A fix for the bug reported in PR30911.
The issue arises when multiple CALLSEQ_BEGIN nodes are unscheduled as
the last node to be unscheduled will gain access to the CallResource
register. But when a node is being picked, only CALLSEQ_END nodes are
checked against the CallResource and have their chains evaluated.
This then means that other CALLSEQ_BEGIN nodes can be scheduled
before the existing call sequence has been finalised. This patch adds
a check against the FrameSetup nodes in DelayForLiveRegs to prevent
this from happening.
Differential Revision: https://reviews.llvm.org/D31536
llvm-svn: 299926
Module::getOrInsertFunction is using C-style vararg instead of
variadic templates.
From a user prospective, it forces the use of an annoying nullptr
to mark the end of the vararg, and there's not type checking on the
arguments. The variadic template is an obvious solution to both
issues.
llvm-svn: 299925
The math works out where it can actually be counter-productive. The probability
calculations correctly handle the case where the alternative is 0 probability,
rely on those calculations.
Includes a test case that demonstrates the problem.
llvm-svn: 299892
Qin may be large, and Succ may be more frequent than BB. Take these both into
account when deciding if tail-duplication is profitable.
llvm-svn: 299891
Merging identical blocks when it doesn't reduce fallthrough. It is common for
the blocks created from critical edge splitting to be identical. We would like
to merge these blocks whenever doing so would not reduce fallthrough.
llvm-svn: 299890
LLVM makes several assumptions about address space 0. However,
alloca is presently constrained to always return this address space.
There's no real way to avoid using alloca, so without this
there is no way to opt out of these assumptions.
The problematic assumptions include:
- That the pointer size used for the stack is the same size as
the code size pointer, which is also the maximum sized pointer.
- That 0 is an invalid, non-dereferencable pointer value.
These are problems for AMDGPU because alloca is used to
implement the private address space, which uses a 32-bit
index as the pointer value. Other pointers are 64-bit
and behave more like LLVM's notion of generic address
space. By changing the address space used for allocas,
we can change our generic pointer type to be LLVM's generic
pointer type which does have similar properties.
llvm-svn: 299888
Summary:
For SETCC we aren't calculating the KnownZero bits at all. I've copied the code from computeKnownZero over for this.
For AssertZExt we were only setting KnownZero for bits that were demanded. But the upper bits are zero whether they were demanded or not.
I'm interested in fixing this because my belief is the first part of the ISD::AND handling code in SimplifyDemandedBits largely exists because of these two bugs. In that code we go to computeKnownBits for the LHS and optimize a RHS constant. Because computeKnownBits handles SETCC and AssertZExt correctly we get better information sometimes than when we call SimplifyDemandedBits on the LHS later. With these two issues fixed in SimplifyDemandedBits I was able to remove that computeKnownBits call and still pass all X86 tests. I'll submit that change in a separate patch.
Reviewers: RKSimon, spatel
Reviewed By: RKSimon
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D31715
llvm-svn: 299839
The original instruction might get legalized and erased and expanded
into intermediate instructions and the intermediate instructions might
fail legalization. This end up in reporting GISelFailure on the erased
instruction.
Instead report GISelFailure on the intermediate instruction which failed
legalization.
Reviewed by: ab
llvm-svn: 299802
This reverts commit r299766. This change appears to have broken the MIPS
buildbots. Reverting while I investigate.
Revert "[mips] Remove usage of debug only variable (NFC)"
This reverts commit r299769. Follow up commit.
llvm-svn: 299788
By target hookifying getRegisterType, getNumRegisters, getVectorBreakdown,
backends can request that LLVM to scalarize vector types for calls
and returns.
The MIPS vector ABI requires that vector arguments and returns are passed in
integer registers. With SelectionDAG's new hooks, the MIPS backend can now
handle LLVM-IR with vector types in calls and returns. E.g.
'call @foo(<4 x i32> %4)'.
Previously these cases would be scalarized for the MIPS O32/N32/N64 ABI for
calls and returns if vector types were not legal. If vector types were legal,
a single 128bit vector argument would be assigned to a single 32 bit / 64 bit
integer register.
By teaching the MIPS backend to inspect the original types, it can now
implement the MIPS vector ABI which requires a particular method of
scalarizing vectors.
Previously, the MIPS backend relied on clang to scalarize types such as "call
@foo(<4 x float> %a) into "call @foo(i32 inreg %1, i32 inreg %2, i32 inreg %3,
i32 inreg %4)".
This patch enables the MIPS backend to take either form for vector types.
Reviewers: zoran.jovanovic, jaydeep, vkalintiris, slthakur
Differential Revision: https://reviews.llvm.org/D27845
llvm-svn: 299766
The new codepath has been in the tree for years, and there isn't any
reason to use two codepaths here.
Differential Revision: https://reviews.llvm.org/D30596
llvm-svn: 299723
Module::getOrInsertFunction is using C-style vararg instead of
variadic templates.
From a user prospective, it forces the use of an annoying nullptr
to mark the end of the vararg, and there's not type checking on the
arguments. The variadic template is an obvious solution to both
issues.
Patch by: Serge Guelton <serge.guelton@telecom-bretagne.eu>
Differential Revision: https://reviews.llvm.org/D31070
llvm-svn: 299699
Since the BUILD_VECTOR has already been checked by
isBuildVectorOfConstantSDNodes() in SelectionDAG::getNode() for a
SIGN_EXTEND_INREG, it can be assumed that Op is always either undef or a
ConstantSDNode, and Ops.size() will always equal VT.getVectorNumElements().
llvm-svn: 299647
This is a follow-on to r299096 which added support for fmadd.
Subtract does not have the case where with two multiply operands we commute in
order to fuse with the multiply with the fewer uses.
llvm-svn: 299572
Summary:
Use an explicit work queue instead, to avoid accidentally
causing stack overflows for input with very large CFGs.
Reviewed By: mehdi_amini
Differential Revision: https://reviews.llvm.org/D31681
llvm-svn: 299569
This is a generic combine enabled via target hook to reduce icmp logic as discussed in:
https://bugs.llvm.org/show_bug.cgi?id=32401
It's likely that other targets will want to enable this hook for scalar transforms,
and there are probably other patterns that can use bitwise logic to reduce comparisons.
Note that we are missing an IR canonicalization for these patterns, and we will probably
prefer the pair-of-compares form in IR (shorter, more likely to fold).
Differential Revision: https://reviews.llvm.org/D31483
llvm-svn: 299542
When DAGCombiner visits a SIGN_EXTEND_INREG of a BUILD_VECTOR with
constant operands, a new BUILD_VECTOR node will be created transformed
constants.
Llvm-stress found a case where the new BUILD_VECTOR had constant operands
of an illegal type, because the (legal) element type is in fact not a legal
scalar type.
This patch changes this so that the new BUILD_VECTOR has the same operand
type as the old one.
Review: Eli Friedman, Nirav Dave
https://bugs.llvm.org//show_bug.cgi?id=32422
llvm-svn: 299540
Decouple this setting from EnableIRPA.
To support function calls on AMDGPU, it is necessary to
report the global register usage throughout the kernel's
call graph, so callees need to be handled first.
llvm-svn: 299487
If an instruction has a true dependency, it makes sense for to use that
register for any undef read operands in the same instruction (we'll have
to wait for that register to become available anyway). This logic
was already implemented. However, the code would then still try to
revisit that instruction and break the dependency (and always fail,
since by definition a true dependency has to be live before the
instruction). Avoid revisiting such instructions as a performance
optimization. No functional change.
Differential Revision: https://reviews.llvm.org/D30173
llvm-svn: 299467
Summary:
Lift the restrictions that prevented the tree walking introduced in the
previous change and add support for patterns like:
(G_ADD (G_MUL (G_SEXT $src1), (G_SEXT $src2)), $src3) -> SMADDWrrr $dst, $src1, $src2, $src3
Also adds support for G_SEXT and G_ZEXT to support these cases.
One particular aspect of this that I should draw attention to is that I've
tried to be overly conservative in determining the safety of matches that
involve non-adjacent instructions and multiple basic blocks. This is intended
to be used as a cheap initial check and we may add a more expensive check in
the future. The current rules are:
* Reject if any instruction may load/store (we'd need to check for intervening
memory operations.
* Reject if any instruction has implicit operands.
* Reject if any instruction has unmodelled side-effects.
See isObviouslySafeToFold().
Reviewers: t.p.northover, javed.absar, qcolombet, aditya_nandakumar, ab, rovka
Reviewed By: ab
Subscribers: igorb, dberris, llvm-commits, kristof.beyls
Differential Revision: https://reviews.llvm.org/D30539
llvm-svn: 299430
Summary:
Move the aarch64-type-promotion pass within the existing type promotion framework in CGP.
This change also support forking sexts when a new sext is required for promotion.
Note that change is based on D27853 and I am submitting this out early to provide a better idea on D27853.
Reviewers: jmolloy, mcrosier, javed.absar, qcolombet
Reviewed By: qcolombet
Subscribers: llvm-commits, aemerson, rengolin, mcrosier
Differential Revision: https://reviews.llvm.org/D28680
llvm-svn: 299379
This reverts commit r299047 which is incorrect because the
simplification may result in incorrect propogation of undefs to users of
the folded shuffle.
Thanks to Andrea Di Biagio for pointing this out.
llvm-svn: 299368
This moves the isMask and isShiftedMask functions to be class methods. They now use the MathExtras.h function for single word size and leading/trailing zeros/ones or countPopulation for the multiword size. The previous implementation made multiple temorary memory allocations to do the bitwise arithmetic operations to match the MathExtras.h implementation.
Differential Revision: https://reviews.llvm.org/D31565
llvm-svn: 299362
The code already allowed vector types in via "isInteger" (which might want
a more specific name), so use splat-friendly constant predicates to match
those types.
llvm-svn: 299304
This can only happen when we have a mix of zero and undef elements and the two vectors have a different arrangement of zeros/undefs. The shuffle should eventually be constant folded to all zeros.
Fixes PR32484.
llvm-svn: 299291
REG_SEQUENCE falls into the same category as COPY for operands mapping:
- They don't have MCInstrDesc with register constraints
- The input variable could use whatever register classes
- It is possible to have register class already assigned to the operands
In particular, given REG_SEQUENCE are always target specific because of
the subreg indices. Those indices must apply to the register class of
the definition of the REG_SEQUENCE and therefore, the target must set a
register class to that definition. As a result, the generic code can
always use that register class to derive a valid mapping for a
REG_SEQUENCE.
llvm-svn: 299285
(and (setlt X, 0), (setlt Y, 0)) --> (setlt (and X, Y), 0)
We have 7 similar folds, but this one got away. The fact that the
x86 test with a branch didn't change is probably a separate bug. We
may also be missing this and the related folds in instcombine.
llvm-svn: 299252
Currently ComputeNumSignBits returns the minimum number of sign bits for all elements of vector data, when we may only be interested in one/some of the elements.
This patch adds a DemandedElts argument that allows us to specify the elements we actually care about. The original ComputeNumSignBits implementation calls with a DemandedElts demanding all elements to match current behaviour. Scalar types set this to 1.
I've only added support for BUILD_VECTOR and EXTRACT_VECTOR_ELT so far, all others will default to demanding all elements but can be updated in due course.
Followup to D25691.
Differential Revision: https://reviews.llvm.org/D31311
llvm-svn: 299219
Follow up to D25691, this sets up the plumbing necessary to support vector demanded elements support in known bits calculations in target nodes.
Differential Revision: https://reviews.llvm.org/D31249
llvm-svn: 299201
Now alternatively to the TargetOption.AllowFPOpFusion global flag, FMUL->FADD
can also use the per operation FMF to allow fusion.
The idea here is not to port everything to the new scheme (e.g. fused
multiply-and-sub will be ported later) but that this work all the way from
clang.
The transformation is conditionalized on *both* the FADD and the FMUL having
the FMF contract flag.
Differential Revision: https://reviews.llvm.org/D31169
llvm-svn: 299096
In the long-term, we want to replace statistics with something
finer-grained that lets us gather per-function data.
Remarks are that replacement.
Create an ORE instance in SelectionDAGISel, and pass it to
SelectionDAG.
SelectionDAG was used so that we can emit remarks from all
SelectionDAG-related code, including TargetLowering and DAGCombiner.
This isn't used in the current patch but Adam tells me he's interested
for the fp-contract combines.
Use the ORE instance to emit FastISel failures as remarks (instead of
the mix of dbgs() dumps and statistics that we currently have).
Eventually, we want to have an API that tells us whether remarks are
enabled (http://llvm.org/PR32352) so that we don't emit expensive
remarks (in this case, dumping IR) when it's not needed. For now, use
'isEnabled' as a crude replacement.
This does mean that the replacement for '-fast-isel-verbose' is now
'-pass-remarks-missed=isel'. Additionally, clang users also need to
enable remark diagnostics, using '-Rpass-missed=isel'.
This also removes '-fast-isel-verbose2': there are no static statistics
that we want to only enable in asserts builds, so we can always use
the remarks regardless of the build type.
Differential Revision: https://reviews.llvm.org/D31405
llvm-svn: 299093
Turns out integerPartWidth only explicitly defines the width of the tc functions in the APInt class. Functions that aren't used by APInt implementation itself. Many places in the code base already assume APInt is made up of 64-bit pieces. Explicitly assuming 64-bit here doesn't make that situation much worse. A full audit would need to be done if it ever changes.
llvm-svn: 299059
Instantiation of the MachineVerifierPass through
PassInfo::getNormalCtor would yield a segfault since the default
constructor of the MachineVerifierPass takes a reference to nullptr.
Patch by Simone Pellegrini.
Differential Revision: https://reviews.llvm.org/D31387
llvm-svn: 298987
Properly propagate the FMF from the LLVM IR to this flag.
This is toward moving fp-contraction=fast from an LLVM TargetOption to a
FastMathFlag in order to fix PR25721.
Differential Revision: https://reviews.llvm.org/D31165
llvm-svn: 298961