This new wrapper pass is useful when we want to do branch probability analysis conditionally (e.g. only in PGO mode) but don't want to add one more pass dependence.
Chen Li [Wed, 15 Jul 2015 22:41:13 +0000 (22:41 +0000)]
[LoopUnswitch] Add an else clause to IsTrivialUnswitchCondition() when checking HeaderTerm instruction type
Summary:
This is a trivial code change with no functionality effect.
When LoopUnswitch determines trivial unswitch condition, it checks whether the loop header's terminator instruction is a branch instruction or switch instruction since trivial unswitch condition can only apply to these two instruction types. The current code does not fail the check directly on other instruction types, but check the nullness of LoopExitBB variable instead. The added else clause makes the check fail immediately on other instruction types and makes the code more obvious.
Hans Wennborg [Wed, 15 Jul 2015 22:18:25 +0000 (22:18 +0000)]
test-release.sh: Run both .o files through sed before comparing them
On some systems (e.g. Mac OS X), sed will add a newline to the end of
the output if there wasn't one already. This would cause false
cmp errors since the .o file from Phase 2 was passed through sed and
the one from Phase 3 wasn't. Work around this by passing both through
sed.
TargetRegisterInfo: Provide a way to check assigned registers in getRegAllocationHints()
Pass a const reference to LiveRegMatrix to getRegAllocationHints()
because some targets can prodive better hints if they can test whether a
physreg has been used for register allocation yet.
Alex Lorenz [Wed, 15 Jul 2015 22:14:49 +0000 (22:14 +0000)]
MIR Serialization: Serialize references from the stack objects to named allocas.
This commit serializes the references to the named LLVM alloca instructions from
the stack objects in the machine frame info. This commit adds a field 'Name' to
the struct 'yaml::MachineStackObject'. This new field is used to store the name
of the alloca instruction when the alloca is present and when it has a name.
Paul Robinson [Wed, 15 Jul 2015 22:04:54 +0000 (22:04 +0000)]
Add a "debugger tuning" concept that allows us to fine-tune how we
emit debug info, according to the preferences of the different
debuggers used on various targets.
Darwin and FreeBSD default to tuning for LLDB; PS4 defaults to tuning for
the SCE (Sony Computer Entertainment) debugger. All others default to GDB.
Self-referential constants containing references to a merged function
no longer cause the MergeFunctions pass to infinite loop. Also adds a
reproduction IR which would otherwise fail, which was isolated from a similar
issue in Chromium.
Hans Wennborg [Wed, 15 Jul 2015 21:06:16 +0000 (21:06 +0000)]
Switch the release script to build with CMake by default (PR21561)
It retains the possibility to use the autoconf build with a
command-line option ('-use-autoconf'), and uses that by default on Darwin since
compiler-rt requires it on that platform.
This commit also removes the "Release-64" flavour and related logic. The script
would previously do two builds unless the '-no-64bit' flag was passed, but on
my machine and from those I asked this always ended up producing two 64-bit builds,
causing much confusion.
It also removes the -build-triple option, which caused the --build= flag to
get passed to ./configure. This was presumably intended for cross-compiling,
but none of the release testers use it. If someone does want to pass it,
they can use '-configure-flags --build=foo' instead.
Summary:
This patch allows phi nodes like
%x = phi [ %incptr, ... ] [ %var, ... ]
%incptr = getelementptr %x, 1
to be analyzed by BasicAliasAnalysis.
In aliasPHI, we can detect incoming values that are recursive GEPs with a
constant offset. Instead of trying to analyze a recursive GEP (and failing),
we now ignore it and instead set the size of the memory referenced by
the PHINode to UnknownSize. This represents all the possible memory
locations the pointer represented by the PHINode could be advanced to
by the GEP.
For now, this new behavior is turned off by default to allow debugging of
performance degradations seen with SPEC/x86 and Hexagon benchmarks.
The flag -basicaa-recphi turns it on.
Adrian Prantl [Wed, 15 Jul 2015 17:01:41 +0000 (17:01 +0000)]
Debug Info: Add basic support for external types references.
This is a necessary prerequisite for bootstrapping the emission
of debug info inside modules.
- Adds a FlagExternalTypeRef to DICompositeType.
External types must have a unique identifier.
- External type references are emitted using a forward declaration
with a DW_AT_signature([DW_FORM_ref_sig8]) based on the UID.
Pete Cooper [Wed, 15 Jul 2015 16:36:38 +0000 (16:36 +0000)]
Add missing load/store flags to thumb2 instructions.
These were the cause of a verifier error when building 7zip with
-verify-machineinstrs. Running 'make check' with the verifier
triggered the same error on the test here so i've updated the test
to run the verifier on one of its runs instead of adding a new one.
While looking at this code, there was a stale comment that these
instructions were only used for disassembly. This probably used to
be the case, but they are now used in the 'ARM load / store optimization pass' too.
Bill Schmidt [Wed, 15 Jul 2015 15:45:30 +0000 (15:45 +0000)]
[PPC64LE] Fix vec_sld semantics for little endian
The vec_sld interface provides access to the vsldoi instruction.
Unlike most of the vec_* interfaces, we do not attempt to change the
generated code for vec_sld based on the endian mode. It is too
difficult to correctly infer the desired semantics because of
different element types, and the corrected instruction sequence is
expensive, involving loading a permute control vector and performing a
generalized permute.
For GCC, this was implemented as "Don't touch the vec_sld"
implementation. When it came time for the LLVM implementation, I did
the same thing. However, this was hasty and incorrect. In LLVM's
version of altivec.h, vec_sld was previously defined in terms of the
vec_perm interface. Because vec_perm semantics are adjusted for
little endian, this means that leaving vec_sld untouched causes it to
generate something different for LE than for BE. Not good.
This back-end patch accompanies the changes to altivec.h that change
vec_sld's behavior for little endian. Those changes mean that we see
slightly different code in the back end when trying to recognize a
VSLDOI instruction in isVSLDOIShuffleMask. In particular, a
ShuffleKind of 1 (where the two inputs are identical) must now be
treated the same way as a ShuffleKind of 2 (little endian with
different inputs) when little endian mode is in force. This is
because ShuffleKind of 1 is defined using big-endian numbering.
This has a ripple effect on LowerBUILD_VECTOR, where we create our own
internal VSLDOI instructions. Because these are a ShuffleKind of 1,
they will now have their shift amounts subtracted from 16 when
recognizing the shuffle mask. To avoid problems we have to subtract
them from 16 again before creating the VSLDOI instructions.
There are a couple of other uses of BuildVSLDOI, but these do not need
to be modified because the shift amount is 8, which is unchanged when
subtracted from 16.
Look through PHIs to find additional register sources
- 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:
Andrew Wilkins [Wed, 15 Jul 2015 13:03:08 +0000 (13:03 +0000)]
Expose setPersonalityFn to Go
Summary:
Add Value.SetPersonality to the Go bindings. The Go
bindings' Builder.CreateLandingPad has been updated,
removing the obsolete personality argument.
Background
The personality attribute was removed from LandingPadInst
in r239940, and llvm::Function::setPersonalityFn introduced.
There was no corresponding change to either the C API or
Go bindings. The Go bindings were broken until r239940, but
that change was just to ignore the personality argument.
This broke llgo.
[PM/AA] Fix *numerous* serious bugs in GlobalsModRef found by
inspection.
While we want to handle calls specially in this code because they should
have been modeled by the call graph analysis that precedes it, we should
*not* be re-implementing the predicates for whether an instruction reads
or writes memory. Those are well defined already. Notably, at least the
following issues seem to be clearly missed before:
- Ordered atomic loads can "write" to memory by causing writes from other
threads to become visible. Similarly for ordered atomic stores.
- AtomicRMW instructions quite obviously both read and write to memory.
- AtomicCmpXchg instructions also read and write to memory.
- Fences read and write to memory.
- Invokes of intrinsics or memory allocation functions.
I don't have any test cases, and I suspect this has never really come up
in the real world. But there is no reason why it wouldn't, and it makes
the code simpler to do this the right way.
While here, I've tried to make the loops significantly simpler as well
and added helpful comments as to what is going on.
[SDAG] Optimize unordered comparison in soft-float mode (patch by Anton Nadolskiy)
Current implementation handles unordered comparison poorly in soft-float mode.
Consider (a ULE b) which is a <= b. It is lowered to (ledf2(a, b) <= 0 || unorddf2(a, b) != 0) (in general). We can do better job by lowering it to (__gtdf2(a, b) <= 0).
Such replacement is true for other CMP's (ult, ugt, uge). In general, we just call same function as for ordered case but negate comparison against zero.
Differential Revision: http://reviews.llvm.org/D10804
Hal Finkel [Wed, 15 Jul 2015 08:23:05 +0000 (08:23 +0000)]
[PowerPC] Use the MachineCombiner to reassociate fadd/fmul
This is a direct port of the code from the X86 backend (r239486/r240361), which
uses the MachineCombiner to reassociate (floating-point) adds/muls to increase
ILP, to the PowerPC backend. The rationale is the same.
There is a lot of copy-and-paste here between the X86 code and the PowerPC
code, and we should extract at least some of this into CodeGen somewhere.
However, I don't want to do that until this code is enhanced to handle FMAs as
well. After that, we'll be in a better position to extract the common parts.
Hal Finkel [Wed, 15 Jul 2015 08:23:03 +0000 (08:23 +0000)]
[PowerPC] Extend physical register live range in PPCVSXFMAMutate
If the source of the copy that defines the addend is a physical register, then
its existing live range may not extend to the FMA being mutated. Make sure we
extend the live range of the register to meet the FMA because it will become
its operand in this case.
I don't have an independent test case, but it will be exposed by change to be
committed shortly enabling the use of the machine combiner to do fadd/fmul
reassociation, and will be covered by one of the associated regression tests.
Hal Finkel [Wed, 15 Jul 2015 08:22:23 +0000 (08:22 +0000)]
[MachineCombiner] Work with itineraries
MachineCombiner predicated its use of scheduling-based metrics on
hasInstrSchedModel(), but useful conclusions can be drawn from pipeline
itineraries as well. Almost all of the logic (except for resource tracking in
preservesResourceLen) can be used if we have an itinerary, so enable it in that
case as well.
This will be used by the PowerPC backend in an upcoming commit.
Petr Pavlu [Wed, 15 Jul 2015 08:04:27 +0000 (08:04 +0000)]
[TableGen] Improve decoding options for non-orthogonal instructions
When FixedLenDecoder matches an input bitpattern of form [01]+ with an
instruction bitpattern of form [01?]+ (where 0/1 are static bits and ? are
mixed/variable bits) it passes the input bitpattern to a specific instruction
decoder method which then makes a final decision whether the bitpattern is a
valid instruction or not. This means the decoder must handle all possible
values of the variable bits which sometimes leads to opcode rewrites in the
decoder method when the instructions are not fully orthogonal.
The patch provides a way for the decoder method to say that when it returns
Fail it does not necessarily mean the bitpattern is invalid, but rather that
the bitpattern is definitely not an instruction that is recognized by the
decoder method. The decoder can then try to match the input bitpattern with
other possible instruction bitpatterns.
For example, this allows to solve a situation on AArch64 where the `MSR
(immediate)` instruction has form:
1101 0101 0000 0??? 0100 ???? ???1 1111
but not all values of the ? bits are allowed. The rejected values should be
handled by the `extended MSR (register)` instruction:
1101 0101 000? ???? ???? ???? ???? ????
The decoder will first try to decode an input bitpattern that matches both
bitpatterns as `MSR (immediate)` but currently this puts the decoder method of
`MSR (immediate)` into a situation when it must be able to decode all possible
values of the ? bits, i.e. it would need to rewrite the instruction to `MSR
(register)` when it is not `MSR (immediate)`.
The patch allows to specify that the decoder method cannot determine if the
instruction is valid for all variable values. The decoder method can simply
return Fail when it knows it is definitely not `MSR (immediate)`. The decoder
will then backtrack the decoding and find that it can match the input
bitpattern with the more generic `MSR (register)` bitpattern too.
[vim] Update the syntax to mark REQUIRES lines and not talk about
dejagnu.
I wonder if it would be useful to handle FileCheck prefixes specially?
Especially if we could get some error checking. Suggestions welcome.
Patches more welcome as I have no idea what I'm doing with vim
script....
[vim] Add the IR's comment prefix to the comments list. This allows vim
to intelligently wrap prose written in IR comment blocks. This has
bothered me for roughly ever, and my fellow IRC denziens convinced me to
fix it.
Pete Cooper [Wed, 15 Jul 2015 01:31:26 +0000 (01:31 +0000)]
Use enum instead of unsigned. NFC.
The unsigned opcode argument here was the result of BinaryOperator->getOpcode().
That returns a BinaryOps enum which is more accurate than passing around an
unsigned.
Pete Cooper [Wed, 15 Jul 2015 01:31:23 +0000 (01:31 +0000)]
Use cast<> instead of dyn_cast to remove llvm_unreachable. NFC.
This code was checking if we are an ICmpInst or FCmpInst then throwing
unreachable if we are neither. We must be one or the other, so use a
cast on the FCmpInst case to ensure that we are that case. Then we can
avoid having an unreachable but still catch an error if we ever had another
subclass of CmpInst.
Pete Cooper [Wed, 15 Jul 2015 00:07:57 +0000 (00:07 +0000)]
Change conditional to assert. NFC.
This code was breaking from the case statement if the getStoreSizeInBits()
value was not a multiple of 0. Given that the implementation returns
getStoreSize() * 8, it can only be a multiple of 8.
Pete Cooper [Wed, 15 Jul 2015 00:07:55 +0000 (00:07 +0000)]
Use getStoreSize() instead of getStoreSizeInBits()/8. NFC.
The calls here were both to getStoreSizeInBits() which multiplies by 8.
We then immediately divided by 8. Calling getStoreSize() returns the
values we need without the extra arithmetic.
Summary:
processFunctionBeforeCalleeSavedScan was renamed to determineCalleeSaves and now takes a BitVector parameter as of rL242165, reviewed in http://reviews.llvm.org/D10909
WebAssembly is still marked as experimental and therefore doesn't build by default. It does, however, grep by default! I notice that processFunctionBeforeCalleeSavedScan is still mentioned in a few comments and error messages, which I also fixed.
Hal Finkel [Tue, 14 Jul 2015 22:53:11 +0000 (22:53 +0000)]
[PowerPC] Support symbolic targets in patchpoints
Follow-up r235483, with the corresponding support in PPC. We use a regular call
for symbolic targets (because they're much cheaper than indirect calls).
Hal Finkel [Tue, 14 Jul 2015 22:26:06 +0000 (22:26 +0000)]
[PowerPC] Use the ABI indirect-call protocol for patchpoints
We used to take the address specified as the direct target of the patchpoint
and did no TOC-pointer handling. This, however, as not all that useful,
because MCJIT tends to create a lot of modules, and they have their own TOC
sections. Thus, to call from the generated code to other generated code, you
really need to switch TOC pointers. Make this work as expected, and under
ELFv1, tread the address as the function descriptor address so that the correct
TOC pointer can be loaded.
Rafael Espindola [Tue, 14 Jul 2015 22:18:43 +0000 (22:18 +0000)]
Add support for reading members out of thin archives.
For now the Archive owns the buffers of the thin archive members.
This makes for a simple API, but all the buffers are destructed
only when the archive is destructed. This should be fine since we
close the files after mmap so we should not hit an open file
limit.
Alex Lorenz [Tue, 14 Jul 2015 21:18:25 +0000 (21:18 +0000)]
MIR Printer: move the function 'printReg'. NFC.
This commit moves the function 'printReg' towards the start of the file so that
it can be used by the conversion methods in MIRPrinter and not just the printing
methods in MIPrinter.
Tim Northover [Tue, 14 Jul 2015 21:03:18 +0000 (21:03 +0000)]
GVN: tolerate an instruction being replaced without existing in the leaderboard
Sometimes an incidentally created instruction can duplicate a Value used
elsewhere. It then often doesn't end up in the leader table. If it's later
removed, we attempt to remove it from the leader table and segfault.
Instead we should just ignore the removal request, which won't cause any
problems. The reverse situation, where the original instruction is replaced by
the new one (which you might think could leave the leader table empty) cannot
occur, because the incidental instruction will never be found in the first
place.
[MMX] Use the appropriate instructions for GR64 <-> VR64 copies.
MOVSDto64rr and MOV64toSDrr are defined to convert between FR64 (%xmm)
<-> GR64 registers, not VR64 (%mm) <-> GR64. This is wrong.
I found this by inspection and could not find a suitable testcase for it
since (1) we don't handle MMX bitcasts in Peephole optimizer as to
generate COPYs that (2) could be expanded back to the appropriate x86
instruction in ExpandPostRA.
Switch to use the appropriate instructions: MMX_MOVD64from64rr and
MMX_MOVD64to64rr here.
Hal Finkel [Tue, 14 Jul 2015 20:02:02 +0000 (20:02 +0000)]
[PowerPC] Fix the PPCInstrInfo::getInstrLatency implementation
PowerPC uses itineraries to describe processor pipelines (and dispatch-group
restrictions for P7/P8 cores). Unfortunately, the target-independent
implementation of TII.getInstrLatency calls ItinData->getStageLatency, and that
looks for the largest cycle count in the pipeline for any given instruction.
This, however, yields the wrong answer for the PPC itineraries, because we
don't encode the full pipeline. Because the functional units are fully
pipelined, we only model the initial stages (there are no relevant hazards in
the later stages to model), and so the technique employed by getStageLatency
does not really work. Instead, we should take the maximum output operand
latency, and that's what PPCInstrInfo::getInstrLatency now does.
This caused some test-case churn, including two unfortunate side effects.
First, the new arrangement of copies we get from function parameters now
sometimes blocks VSX FMA mutation (a FIXME has been added to the code and the
test cases), and we have one significant test-suite regression:
In this benchmark we have a loop with a vectorized FP divide, and it with the
new scheduling both divides end up in the same dispatch group (which in this
case seems to cause a problem, although why is not exactly clear). The grouping
structure is hard to predict from the bottom of the loop, and there may not be
much we can do to fix this.
Very few other test-suite performance effects were really significant, but
almost all weakly favor this change. However, in light of the issues
highlighted above, I've left the old behavior available via a
command-line flag.
Dan Liew [Tue, 14 Jul 2015 19:46:19 +0000 (19:46 +0000)]
Fix several issues with the test-release.sh script
* Use the default install prefix (/usr/local) and use DESTDIR instead to
set a temporary install location for tarballing. This is the correct
way to package binary releases (otherwise the temporary install path
ends up in files in the binary release).
* Remove ``-disable-clang`` option. It did not work correctly
(tarballing assumed phase 3 was run) and when doing a release
we should always be doing a three-phased build and test.
Note: Technically we should only be using DESTDIR for the third phase
and use --prefix for the first and second phase because we run the built
clang from phase 1 and 2 (and in general an application's behaviour
may depend on the install prefix). However in the case of clang it
seems to not care what the install prefix was so to simplify the script
we use DESTDIR for all three stages.
[CodeGen] Force emission of personality directive if explicitly specified
Summary:
Before this change, personality directives were not emitted
if there was no invoke left in the function (of course until
recently this also meant that we couldn't know what
the personality actually was). This patch forces personality directives
to still be emitted, unless it is known to be a noop in the absence of
invokes, or the user explicitly specified `nounwind` (and not
`uwtable`) on the function.
Matt Arsenault [Tue, 14 Jul 2015 18:20:33 +0000 (18:20 +0000)]
AMDGPU: Avoid using 64-bit shift for i64 (shl x, 32)
This can be done only with moves which theoretically
will optimize better later.
Although this transform increases the instruction count,
it should be code size / cycle count neutral in the worst
VALU case. It also seems to slightly improve a couple
of testcases due to other DAG combines this exposes.
This is probably slightly worse for the SALU case, so
it might be better to handle this during moveToVALU,
although then you lose some simplifications like
the load width reducing in the simple testcase.
Matt Arsenault [Tue, 14 Jul 2015 17:57:36 +0000 (17:57 +0000)]
AMDGPU/SI: Fix read2 merging into a super register.
If the read2 produced was supposed to be writing into a
super register, it would use the wrong subregister indices.
Fix this by inserting copies, so we only ever write to a vreg_64.
Run the register coalescer again to clean this up, although this
isn't ideal and often does result in an extra move.
Also remove the assert that offset1 > offset0.
There isn't a real reason to not allow this other than a minor
convenience in the compiler, and it doesn't seem worth the effort
of avoiding it.
We have a detailed def/use lists for every physical register in
MachineRegisterInfo anyway, so there is little use in maintaining an
additional bitset of which ones are used.
Removing it frees us from extra book keeping. This simplifies
VirtRegMap.
RAGreedy: Keep track of allocated PhysRegs internally
Do not use MachineRegisterInfo::setPhysRegUsed()/isPhysRegUsed()
anymore. This bitset changes function-global state and is set by the
VirtRegRewriter anyway.
Simply use a bitvector private to RAGreedy.
Tim Northover [Tue, 14 Jul 2015 17:23:55 +0000 (17:23 +0000)]
ARM: add at least one real test for r242123.
The ones committed were orthogonal to the change and would have passed before
that revision. What it *did* do was prevent an assertion failure when
generating object files.
PrologEpilogInserter: Rewrite API to determine callee save regsiters.
This changes TargetFrameLowering::processFunctionBeforeCalleeSavedScan():
- Rename the function to determineCalleeSaves()
- Pass a bitset of callee saved registers by reference, thus avoiding
the function-global PhysRegUsed bitset in MachineRegisterInfo.
- Without PhysRegUsed the implementation is fine tuned to not save
physcial registers which are only read but never modified.
projects / llvm / log