Fix for D12561 - we weren't correctly ensuring that the base element for extension was moved to start on a boundary suitable for UNPCKL/H
llvm-svn: 248536
These are necessary for implementing mem_fence for
OpenCL 2.0.
The VI assembler tests are disabled since it seems to be
using the wrong encoding or opcode.
llvm-svn: 248532
The pre- and post-increment version update the base register, but the post-
version was defined incorrectly. There is no test case as we don't currently
generate these instructions, but I plan on changing that in the near future.
llvm-svn: 248528
Currently, the availability of DSP instructions (ACLE 6.4.7) is handled in a
hand-rolled tricky condition block in tools/clang/lib/Basic/Targets.cpp, with
a FIXME: attached.
This patch changes the handling of +t2dsp to be in line with other
architecture extensions.
Following a revert of r248152 and new review comments, this patch also includes
renaming FeatureDSPThumb2 -> FeatureDSP, hasThumb2DSP() -> hasDSP(), etc.
The spelling of "t2dsp" is preserved, pending a further investigation of its
possible external usage.
Differential Revision: http://reviews.llvm.org/D12937
llvm-svn: 248519
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
Instead of always inserting a copy in case
the super register is itself a subregister,
only extract to the super reg class if this is
actually the case.
This shouldn't really change codegen, but
makes looking at the output of SIFixSGPRCopies
easier to read.
llvm-svn: 248467
This time, the issue is that we weren't accounting for the possibility that
aligned DPRs could have been stored after the final "push" in a prologue. When
that happened we effectively moved a "sub sp, #N" from below the aligned stores
to above them, and everything went to pot.
To make it worse, I'd actually committed something testing that we produced
wrong code, so the test update is tiny.
llvm-svn: 248437
Add two new ways of accessing the unsafe stack pointer:
* At a fixed offset from the thread TLS base. This is very similar to
StackProtector cookies, but we plan to extend it to other backends
(ARM in particular) soon. Bionic-side implementation here:
https://android-review.googlesource.com/170988.
* Via a function call, as a fallback for platforms that provide
neither a fixed TLS slot, nor a reasonable TLS implementation (i.e.
not emutls).
This is a re-commit of a change in r248357 that was reverted in
r248358.
llvm-svn: 248405
The BEXTR comments didn't make sense before, we may want to extend the
FP logic transform to work on vectors, and this way is more beautiful.
llvm-svn: 248404
This reverts r248388 and fixes the underlying bug: hasAddr64 was initialized
in runOnMachineFunction, but runOnMachineFunction isn't ever called in
CodeGen/WebAssembly/global.ll since that testcase has no functions. The fix
here is to use AsmPrinter's getPointerSize() as needed to determine the
pointer size instead.
llvm-svn: 248394
The ARM backend has some logic that only allows the fast-isel to be enabled for
subtargets where it is known to be stable. This adds a backend option to
override this and force the fast-isel to be used for any target, to allow it to
be tested.
This is an ARM-specific option, because no other backend disables the fast-isel
on a per-subtarget basis.
llvm-svn: 248369
This patches removes the x86.sse41.pmovsx* intrinsics, provides a suitable upgrade path and updates relevant tests to sign extend a subvector instead.
LLVM counterpart to D12835
Differential Revision: http://reviews.llvm.org/D13002
llvm-svn: 248368
Summary:
It is fairly common to call SE->getConstant(Ty, 0) or
SE->getConstant(Ty, 1); this change makes such uses a little bit
briefer.
I've refactored the call sites I could find easily to use getZero /
getOne.
Reviewers: hfinkel, majnemer, reames
Subscribers: sanjoy, llvm-commits
Differential Revision: http://reviews.llvm.org/D12947
llvm-svn: 248362
Add two new ways of accessing the unsafe stack pointer:
* At a fixed offset from the thread TLS base. This is very similar to
StackProtector cookies, but we plan to extend it to other backends
(ARM in particular) soon. Bionic-side implementation here:
https://android-review.googlesource.com/170988.
* Via a function call, as a fallback for platforms that provide
neither a fixed TLS slot, nor a reasonable TLS implementation (i.e.
not emutls).
llvm-svn: 248357
ARM counterpart to r248291:
In the comparison failure block of a cmpxchg expansion, the initial
ldrex/ldxr will not be followed by a matching strex/stxr.
On ARM/AArch64, this unnecessarily ties up the execution monitor,
which might have a negative performance impact on some uarchs.
Instead, release the monitor in the failure block.
The clrex instruction was designed for this: use it.
Also see ARMARM v8-A B2.10.2:
"Exclusive access instructions and Shareable memory locations".
Differential Revision: http://reviews.llvm.org/D13033
llvm-svn: 248294
In the comparison failure block of a cmpxchg expansion, the initial
ldrex/ldxr will not be followed by a matching strex/stxr.
On ARM/AArch64, this unnecessarily ties up the execution monitor,
which might have a negative performance impact on some uarchs.
Instead, release the monitor in the failure block.
The clrex instruction was designed for this: use it.
Also see ARMARM v8-A B2.10.2:
"Exclusive access instructions and Shareable memory locations".
Differential Revision: http://reviews.llvm.org/D13033
llvm-svn: 248291
Summary:
Almost no functional change since the InstrItinData's have been duplicated.
The one functional change is to remove IIBranch from the MSA branches. The
classes will be assigned to the MSA instructions as part of implementing
the P5600 scheduler.
II_IndirectBranchPseudo and II_ReturnPseudo can probably be removed. I've
preserved the itinerary information for the corresponding pseudo
instructions to avoid making a functional change to these pseudos in
this patch.
Reviewers: vkalintiris
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D12189
llvm-svn: 248273
Summary:
The only instructions left in IIAlu are MIPS16 specific. We're not
implementing a MIPS16 scheduler at this time so rename the class to make it
obvious that they are MIPS16 instructions.
Reviewers: vkalintiris
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D12188
llvm-svn: 248267
The C standard has historically not specified whether or not these functions should raise the inexact flag. Traditionally on Darwin, these functions *did* raise inexact, and the llvm lowerings followed that conventions. n1778 (C bindings for IEEE-754 (2008)) clarifies that these functions should not set inexact. This patch brings the lowerings for arm64 and x86 in line with the newly specified behavior. This also lets us fold some logic into TD patterns, which is nice.
Differential Revision: http://reviews.llvm.org/D12969
llvm-svn: 248266
Summary:
Based on a patch by David Chisnall. I've modified the original patch as follows:
* Moved the expansion to the TargetStreamers so that the directive isn't
expanded when emitting assembly.
* Fixed an operand order bug.
* Changed the move instructions from DADDu to OR to match recent changes to GAS.
Reviewers: vkalintiris
Subscribers: llvm-commits, emaste, seanbruno, theraven
Differential Revision: http://reviews.llvm.org/D13017
llvm-svn: 248258
Summary:
No functional change since no InstrItinData is provided.
Reviewers: vkalintiris
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D12190
llvm-svn: 248257
This patch generalizes the lowering of shuffles as zero extensions to allow extensions that don't start from the first element. It now recognises extensions starting anywhere in the lower 128-bits or at the start of any higher 128-bit lane.
The motivation was to reduce the number of high cost pshufb calls, but it also improves the SSE2 case as well.
Differential Revision: http://reviews.llvm.org/D12561
llvm-svn: 248250
The vext pseudo-instruction takes the number of elements that need to be
extracted, not the number of bytes. Hence, use the number of elements
directly instead of scaling them with a factor.
Reviewers: Silviu Baranga, James Molloy
(not reflected in the differential revision)
Differential Revision: http://reviews.llvm.org/D12974
llvm-svn: 248208
The ISD::FPOW and ISD::FSINCOS opcodes default to Legal, but there
is no legal instruction for those on SystemZ. This could cause
LLVM internal errors. Fixed by setting the operation action to
Expand for those opcodes.
Also added test cases for all other LLVM IR intrinsics that should
generate a library call. (Those already work correctly since the
default operation action is fine.)
llvm-svn: 248180
Currently, the availability of DSP instructions (ACLE 6.4.7) is handled in a
hand-rolled tricky condition block in tools/clang/lib/Basic/Targets.cpp, with
a FIXME: attached.
This patch changes the handling of +t2dsp to be in line with other
architecture extensions.
Following review comments, also updating the description of FeatureDSPThumb2
in ARM.td.
Differential Revision: http://reviews.llvm.org/D12937
llvm-svn: 248152
Summary:
Also tightened up the test and made a trivial fix to prevent double-newline
after emitting .cpsetup directives.
Reviewers: vkalintiris
Subscribers: seanbruno, emaste, llvm-commits
Differential Revision: http://reviews.llvm.org/D12956
llvm-svn: 248143
Now that we have fast vector CTPOP implementations we can use this to speed up vector CTTZ using the pattern (cttz(x) = ctpop((x & -x) - 1))
Additionally, for AVX512CD that provides lzcnt instructions we can use the pattern (cttz_undef(x) = (width - 1) - ctlz(x & -x))
Differential Revision: http://reviews.llvm.org/D12663
llvm-svn: 248091
In ARMBaseInstrInfo::isProfitableToIfCvt(), there is a simple cost model in which the number of cycles is scaled by a probability to estimate the cost. However, when the number of cycles is small (which is usually the case), there is a precision issue after the computation. To avoid this issue, this patch scales those cycles by 1024 (chosen to make the multiplication a litter faster) before they are scaled by the probability. Other variables are also scaled up for the final comparison.
Differential Revision: http://reviews.llvm.org/D12742
llvm-svn: 248018
Summary:
For bitfield insert OR matching, check both operands for larger pattern
first before checking for smaller pattern.
Add pattern for unsigned bitfield insert-in-zero done with SHL+AND.
Resolves PR21631.
Reviewers: jmolloy, t.p.northover
Subscribers: aemerson, rengolin, llvm-commits, mcrosier
Differential Revision: http://reviews.llvm.org/D12908
llvm-svn: 248006
Summary:
Some values of 'reglist' are reserved and cause the disassembler to read past
the end of the Regs array. Treat lwm32's containing reserved values as invalid
instructions.
Reviewers: zoran.jovanovic
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D12959
llvm-svn: 247990
This makes catchret look more like a branch, and less like a weird use
of BlockAddress. It also lets us get away from
llvm.x86.seh.restoreframe, which relies on the old parentfpoffset label
arithmetic.
llvm-svn: 247936
Summary:
This assembler directive is used in O32 PIC to restore the current function's $gp after executing JAL's. The $gp is first stored on the stack at a user-specified offset.
It has the following format: ".cprestore 8" (where 8 is the offset).
This fixes llvm.org/PR20967.
Patch by Toma Tabacu.
Reviewers: seanbruno, tomatabacu
Subscribers: brooks, seanbruno, emaste, llvm-commits
Differential Revision: http://reviews.llvm.org/D6267
llvm-svn: 247897
AVX-512 does not provide an instruction that shuffles mask register. So I do the following way:
mask-2-simd , shuffle simd , simd-2-mask
Differential Revision: http://reviews.llvm.org/D12727
llvm-svn: 247876
Clang now passes the adjectives as an argument to catchpad.
Getting the CatchObj working is simply a matter of threading another
static alloca through codegen, first as an alloca, then as a frame
index, and finally as a frame offset.
llvm-svn: 247844
Otherwise we'd try to emit the thunk that passes the LSDA to
__CxxFrameHandler3. We don't emit the LSDA if there were no landingpads,
so we'd end up with an assembler error when trying to write the COFF
object.
llvm-svn: 247820
This pass implements a simple algorithm for conversion from CFG to
wasm's structured control flow. It doesn't yet handle multiple-entry
loops; that will be added in a future patch.
It also adds initial support for switch statements.
Differential Revision: http://reviews.llvm.org/D12735
llvm-svn: 247818
After D10403, we had FMF in the DAG but disabled by default. Nick reported no crashing errors after some stress testing,
so I enabled them at r243687. However, Escha soon notified us of a bug not covered by any in-tree regression tests:
if we don't propagate the flags, we may fail to CSE DAG nodes because differing FMF causes them to not match. There is
one test case in this patch to prove that point.
This patch hopes to fix or leave a 'TODO' for all of the in-tree places where we create nodes that are FMF-capable. I
did this by putting an assert in SelectionDAG.getNode() to find any FMF-capable node that was being created without FMF
( D11807 ). I then ran all regression tests and test-suite and confirmed that everything passes.
This patch exposes remaining work to get DAG FMF to be fully functional: (1) add the flags to non-binary nodes such as
FCMP, FMA and FNEG; (2) add the flags to intrinsics; (3) use the flags as conditions for transforms rather than the
current global settings.
Differential Revision: http://reviews.llvm.org/D12095
llvm-svn: 247815
When trying emit a stack adjustments using pops, frame lowering selects an
arbitrary free GPR. It should always select one from an appropriate class...
This fixes PR24649.
Patch by: amjad.aboud@intel.com
Differential Revision: http://reviews.llvm.org/D12609
llvm-svn: 247785
This is the mirror image of r242395.
When X86FrameLowering::emitEpilogue() looks for where to insert the %esp addition that
deallocates stack space used for local allocations, it assumes that any sequence of pop
instructions from function exit backwards consists purely of restoring callee-save registers.
This may be false, since from some point backward, the pops may be clean-up of stack space
allocated for arguments to a call.
Patch by: amjad.aboud@intel.com
Differential Revision: http://reviews.llvm.org/D12688
llvm-svn: 247784
Under certain circumstances, tryBuildVectorShuffle would attempt to
create a BUILD_VECTOR node with an invalid combination of types.
This happened when one of the components of the original BUILD_VECTOR
was itself a TRUNCATE node. That TRUNCATE was stripped off during
intermediate processing to simplify code, but when adding the node
back to the result vector, we still need it to get the type right.
llvm-svn: 247694
Summary:
This is the first patch in the series to migrate Triple's (which are ambiguous)
to TargetTuple's (which aren't).
For the moment, TargetTuple simply passes all requests to the Triple object it
holds. Once it has replaced Triple, it will start to implement the interface in
a more suitable way.
This change makes some changes to the public C++ API. In particular,
InitMCSubtargetInfo(), createMCRelocationInfo(), and createMCSymbolizer()
now take TargetTuples instead of Triples. The other public C++ API's have
been left as-is for the moment to reduce patch size.
This commit also contains a trivial patch to clang to account for the C++ API
change. Thanks go to Pavel Labath for fixing LLDB for me.
Reviewers: rengolin
Subscribers: jyknight, dschuff, arsenm, rampitec, danalbert, srhines, javed.absar, dsanders, echristo, emaste, jholewinski, tberghammer, ted, jfb, llvm-commits, rengolin
Differential Revision: http://reviews.llvm.org/D10969
llvm-svn: 247692
Summary:
This is the first patch in the series to migrate Triple's (which are ambiguous)
to TargetTuple's (which aren't).
For the moment, TargetTuple simply passes all requests to the Triple object it
holds. Once it has replaced Triple, it will start to implement the interface in
a more suitable way.
This change makes some changes to the public C++ API. In particular,
InitMCSubtargetInfo(), createMCRelocationInfo(), and createMCSymbolizer()
now take TargetTuples instead of Triples. The other public C++ API's have
been left as-is for the moment to reduce patch size.
This commit also contains a trivial patch to clang to account for the C++ API
change.
Reviewers: rengolin
Subscribers: jyknight, dschuff, arsenm, rampitec, danalbert, srhines, javed.absar, dsanders, echristo, emaste, jholewinski, tberghammer, ted, jfb, llvm-commits, rengolin
Differential Revision: http://reviews.llvm.org/D10969
llvm-svn: 247683
Summary:
Added support for the following instructions:
CACHEE, LBE, LBUE, LHE, LHUE, LWE, LLE, LWLE, LWRE, PREFE,
SBE, SHE, SWE, SCE, SWLE, SWRE, TLBINV, TLBINVF
This required adding some infrastructure for the EVA ASE.
Patch by Scott Egerton.
Reviewers: vkalintiris, dsanders
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11139
llvm-svn: 247669
Summary:
These operands had the same purpose, however the MipsMemSimm9GPRAsmOperand
operand was only for micromips32r6 and the MipsMemSimm9AsmOperand did not
have a ParserMatchClass.
Patch by Scott Egerton
Reviewers: vkalintiris, dsanders
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D12730
llvm-svn: 247573
Turning (op x (mul y k)) into (op x (lsl (mul y k>>n) n)) is beneficial when
we can do the lsl as a shifted operand and the resulting multiply constant is
simpler to generate.
Do this by doing the transformation when trying to select a shifted operand,
as that ensures that it actually turns out better (the alternative would be to
do it in PreprocessISelDAG, but we don't know for sure there if extracting the
shift would allow a shifted operand to be used).
Differential Revision: http://reviews.llvm.org/D12196
llvm-svn: 247569
The MipsTargetELFStreamer can receive ABI info from many sources. For example,
from the MipsAsmParser instance. Lifetime of the MipsAsmParser can be shorter
than MipsTargetELFStreamer's lifetime. In that case we get a dangling pointer
to MipsABIInfo.
Differential Revision: http://reviews.llvm.org/D12805
llvm-svn: 247546
KNL does not have VXORPS, VORPS for 512-bit values.
I use integer VPXOR, VPOR that actually do the same.
X86ISD::FXOR/FOR are generated as a result of FSUB combining.
Differential Revision: http://reviews.llvm.org/D12753
llvm-svn: 247523
The changes in:
test/CodeGen/X86/machine-cp.ll
are just due to scheduling differences after some logic instructions were reassociated.
llvm-svn: 247516
Summary: This fixes a variety of typos in docs, code and headers.
Subscribers: jholewinski, sanjoy, arsenm, llvm-commits
Differential Revision: http://reviews.llvm.org/D12626
llvm-svn: 247495
realignment should be forced.
With this commit, we can now force stack realignment when doing LTO and
do so on a per-function basis. Also, add a new cl::opt option
"stackrealign" to CommandFlags.h which is used to force stack
realignment via llc's command line.
Out-of-tree projects currently using -force-align-stack to force stack
realignment should make changes to attach the attribute to the functions
in the IR.
Differential Revision: http://reviews.llvm.org/D11814
llvm-svn: 247450
We used to have this magic "hasLoadLinkedStoreConditional()" callback,
which really meant two things:
- expand cmpxchg (to ll/sc).
- expand atomic loads using ll/sc (rather than cmpxchg).
Remove it, and, instead, introduce explicit callbacks:
- bool shouldExpandAtomicCmpXchgInIR(inst)
- AtomicExpansionKind shouldExpandAtomicLoadInIR(inst)
Differential Revision: http://reviews.llvm.org/D12557
llvm-svn: 247429
The Win32 EH runtime caller does not preserve EBP, even though it does
preserve the CSRs (EBX, ESI, EDI) for us. The result was that each
finally funclet call would leave the frame pointer off by 12 bytes.
llvm-svn: 247348
The (mostly-deprecated) SelectionDAG-based ILPListDAGScheduler scheduler
was making poor scheduling decisions, causing high register pressure and
extraneous register spills.
Switching to the newer machine scheduler generates better code -- even
without there being a machine model defined for SPARC yet.
(Actually committing the test changes too, this time, unlike r247315)
llvm-svn: 247343
The (mostly-deprecated) SelectionDAG-based ILPListDAGScheduler scheduler
was making poor scheduling decisions, causing high register pressure and
extraneous register spills.
Switching to the newer machine scheduler generates better code -- even
without there being a machine model defined for SPARC yet.
llvm-svn: 247315
Except the changes that defined virtual destructors as =default, because that
ran into problems with GCC 4.7 and overriding methods that weren't noexcept.
llvm-svn: 247298
The tests in isVTRNMask and isVTRN_v_undef_Mask should also check that the elements of the upper and lower half of the vectorshuffle occur in the correct order when both halves are used. Without this test the code assumes that it is correct to use vector transpose (vtrn) for the masks <1, 1, 0, 0> and <1, 3, 0, 2>, among others, but the transpose actually incorrectly generates shuffles for <0, 0, 1, 1> and <0, 2, 1, 3> in this case.
Patch by Jeroen Ketema!
llvm-svn: 247254
The changes in this patch are as follows:
1. Modify the emitPrologue and emitEpilogue methods to work properly when the prologue and epilogue blocks are not the first/last blocks in the function
2. Fix a bug in PPCEarlyReturn optimization caused by an empty entry block in the function
3. Override the runShrinkWrap PredicateFtor (defined in TargetMachine) to check whether shrink wrapping should run:
Shrink wrapping will run on PPC64 (Little Endian and Big Endian) unless -enable-shrink-wrap=false is specified on command line
A new test case, ppc-shrink-wrapping.ll was created based on the existing shrink wrapping tests for x86, arm, and arm64.
Phabricator review: http://reviews.llvm.org/D11817
llvm-svn: 247237
First, we need to teach isFrameOffsetLegal about STNP.
It already knew about the STP/LDP variants, but those were probably
never exercised, because it's only the load/store optimizer that
generates STP/LDP, and the only user of the method is frame lowering,
which runs earlier.
The STP/LDP cases were wrong: they didn't take into account the fact
that they return two results, not one, so the immediate offset will be
the 4th operand, not the 3rd.
Follow-up to r247234.
llvm-svn: 247236
We could go through the load/store optimizer and match STNP where
we would have matched a nontemporal-annotated STP, but that's not
reliable enough, as an opportunistic optimization.
Insetad, we can guarantee emitting STNP, by matching them at ISel.
Since there are no single-input nontemporal stores, we have to
resort to some high-bits-extracting trickery to generate an STNP
from a plain store.
Also, we need to support another, LDP/STP-specific addressing mode,
base + signed scaled 7-bit immediate offset.
For now, only match the base. Let's make it smart separately.
Part of PR24086.
llvm-svn: 247231
All of the complexity is in cleanupret, and it mostly follows the same
codepaths as catchret, except it doesn't take a return value in RAX.
This small example now compiles and executes successfully on win32:
extern "C" int printf(const char *, ...) noexcept;
struct Dtor {
~Dtor() { printf("~Dtor\n"); }
};
void has_cleanup() {
Dtor o;
throw 42;
}
int main() {
try {
has_cleanup();
} catch (int) {
printf("caught it\n");
}
}
Don't try to put the cleanup in the same function as the catch, or Bad
Things will happen.
llvm-svn: 247219
The 32-bit tables don't actually contain PC range data, so emitting them
is incredibly simple.
The 64-bit tables, on the other hand, use the same table for state
numbering as well as label ranges. This makes things more difficult, so
it will be implemented later.
llvm-svn: 247192
With subregister liveness enabled we can detect the case where only
parts of a register are live in, this is expressed as a 32bit lanemask.
The current code only keeps registers in the live-in list and therefore
enumerated all subregisters affected by the lanemask. This turned out to
be too conservative as the subregister may also cover additional parts
of the lanemask which are not live. Expressing a given lanemask by
enumerating a minimum set of subregisters is computationally expensive
so the best solution is to simply change the live-in list to store the
lanemasks as well. This will reduce memory usage for targets using
subregister liveness and slightly increase it for other targets
Differential Revision: http://reviews.llvm.org/D12442
llvm-svn: 247171
with the new pass manager, and no longer relying on analysis groups.
This builds essentially a ground-up new AA infrastructure stack for
LLVM. The core ideas are the same that are used throughout the new pass
manager: type erased polymorphism and direct composition. The design is
as follows:
- FunctionAAResults is a type-erasing alias analysis results aggregation
interface to walk a single query across a range of results from
different alias analyses. Currently this is function-specific as we
always assume that aliasing queries are *within* a function.
- AAResultBase is a CRTP utility providing stub implementations of
various parts of the alias analysis result concept, notably in several
cases in terms of other more general parts of the interface. This can
be used to implement only a narrow part of the interface rather than
the entire interface. This isn't really ideal, this logic should be
hoisted into FunctionAAResults as currently it will cause
a significant amount of redundant work, but it faithfully models the
behavior of the prior infrastructure.
- All the alias analysis passes are ported to be wrapper passes for the
legacy PM and new-style analysis passes for the new PM with a shared
result object. In some cases (most notably CFL), this is an extremely
naive approach that we should revisit when we can specialize for the
new pass manager.
- BasicAA has been restructured to reflect that it is much more
fundamentally a function analysis because it uses dominator trees and
loop info that need to be constructed for each function.
All of the references to getting alias analysis results have been
updated to use the new aggregation interface. All the preservation and
other pass management code has been updated accordingly.
The way the FunctionAAResultsWrapperPass works is to detect the
available alias analyses when run, and add them to the results object.
This means that we should be able to continue to respect when various
passes are added to the pipeline, for example adding CFL or adding TBAA
passes should just cause their results to be available and to get folded
into this. The exception to this rule is BasicAA which really needs to
be a function pass due to using dominator trees and loop info. As
a consequence, the FunctionAAResultsWrapperPass directly depends on
BasicAA and always includes it in the aggregation.
This has significant implications for preserving analyses. Generally,
most passes shouldn't bother preserving FunctionAAResultsWrapperPass
because rebuilding the results just updates the set of known AA passes.
The exception to this rule are LoopPass instances which need to preserve
all the function analyses that the loop pass manager will end up
needing. This means preserving both BasicAAWrapperPass and the
aggregating FunctionAAResultsWrapperPass.
Now, when preserving an alias analysis, you do so by directly preserving
that analysis. This is only necessary for non-immutable-pass-provided
alias analyses though, and there are only three of interest: BasicAA,
GlobalsAA (formerly GlobalsModRef), and SCEVAA. Usually BasicAA is
preserved when needed because it (like DominatorTree and LoopInfo) is
marked as a CFG-only pass. I've expanded GlobalsAA into the preserved
set everywhere we previously were preserving all of AliasAnalysis, and
I've added SCEVAA in the intersection of that with where we preserve
SCEV itself.
One significant challenge to all of this is that the CGSCC passes were
actually using the alias analysis implementations by taking advantage of
a pretty amazing set of loop holes in the old pass manager's analysis
management code which allowed analysis groups to slide through in many
cases. Moving away from analysis groups makes this problem much more
obvious. To fix it, I've leveraged the flexibility the design of the new
PM components provides to just directly construct the relevant alias
analyses for the relevant functions in the IPO passes that need them.
This is a bit hacky, but should go away with the new pass manager, and
is already in many ways cleaner than the prior state.
Another significant challenge is that various facilities of the old
alias analysis infrastructure just don't fit any more. The most
significant of these is the alias analysis 'counter' pass. That pass
relied on the ability to snoop on AA queries at different points in the
analysis group chain. Instead, I'm planning to build printing
functionality directly into the aggregation layer. I've not included
that in this patch merely to keep it smaller.
Note that all of this needs a nearly complete rewrite of the AA
documentation. I'm planning to do that, but I'd like to make sure the
new design settles, and to flesh out a bit more of what it looks like in
the new pass manager first.
Differential Revision: http://reviews.llvm.org/D12080
llvm-svn: 247167
Instead of extracting both 32-bit components from the 128-bit
register. This produces fewer copies and is easier for
the copy peephole optimizer to understand and see the actual uses
as extracts from a reg_sequence.
This avoids needing to handle subregister composing in the
PeepholeOptimizer's ValueTracker for this case.
llvm-svn: 247162
Simon Pilgrim