Lang Hames [Fri, 20 Jul 2018 18:31:53 +0000 (18:31 +0000)]
[ORC] Add new symbol lookup methods to ExecutionSessionBase in preparation for
deprecating SymbolResolver and AsynchronousSymbolQuery.
Both lookup overloads take a VSO search order to perform the lookup. The first
overload is non-blocking and takes OnResolved and OnReady callbacks. The second
is blocking, takes a boolean flag to indicate whether to wait until all symbols
are ready, and returns a SymbolMap. Both overloads take a RegisterDependencies
function to register symbol dependencies (if any) on the query.
Lang Hames [Fri, 20 Jul 2018 18:31:52 +0000 (18:31 +0000)]
[ORC] Simplify VSO::lookupFlags to return the flags map.
This discards the unresolved symbols set and returns the flags map directly
(rather than mutating it via the first argument).
The unresolved symbols result made it easy to chain lookupFlags calls, but such
chaining should be rare to non-existant (especially now that symbol resolvers
are being deprecated) so the simpler method signature is preferable.
Lang Hames [Fri, 20 Jul 2018 18:31:50 +0000 (18:31 +0000)]
[ORC] Replace SymbolResolvers in the new ORC layers with search orders on VSOs.
A search order is a list of VSOs to be searched linearly to find symbols. Each
VSO now has a search order that will be used when fixing up definitions in that
VSO. Each VSO's search order defaults to just that VSO itself.
This is a first step towards removing symbol resolvers from ORC altogether. In
practice symbol resolvers tended to be used to implement a search order anyway,
sometimes with additional programatic generation of symbols. Now that VSOs
support programmatic generation of definitions via fallback generators, search
orders provide a cleaner way to achieve the desired effect (while removing a lot
of boilerplate).
[X86] Remove isel patterns for MOVSS/MOVSD ISD opcodes with integer types.
Ideally our ISD node types going into the isel table would have types consistent with their instruction domain. This prevents us having to duplicate patterns with different types for the same instruction.
Unfortunately, it seems our shuffle combining is currently relying on this a little remove some bitcasts. This seems to enable some switching between shufps and shufd. Hopefully there's some way we can address this in the combining.
[X86] Remove what appear to be unnecessary uses of DCI.CombineTo
CombineTo is most useful when you need to replace multiple results, avoid the worklist management, or you need to something else after the combine, etc. Otherwise you should be able to just return the new node and let DAGCombiner go through its usual worklist code.
All of the places changed in this patch look to be standard cases where we should be able to use the more stand behavior of just returning the new node.
This adds initial support for a demangling library (LLVMDemangle)
and tool (llvm-undname) for demangling Microsoft names. This
doesn't cover 100% of cases and there are some known limitations
which I intend to address in followup patches, at least until such
time that we have (near) 100% test coverage matching up with all
of the test cases in clang/test/CodeGenCXX/mangle-ms-*.
[MemorySSA] Add API to update MemoryPhis, following CFG changes.
Summary:
When splitting predecessors in BasicBlockUtils, we create a new block as an immediate predecessor of the original BB, then we connect a given set of predecessors to the new block.
The API in this patch will be used to update MemoryPhis for this CFG change.
If all predecessors are being moved, we move the MemoryPhi directly. Otherwise we create a new MemoryPhi in the NewBB and populate its incoming values, while deleting them from BB's Phi.
[Split from D45299 for easier review]
This is a new modernized VS integration installer. It adds a
Visual Studio .sln file which, when built, outputs a VSIX that can
be used to install ourselves as a "real" Visual Studio Extension.
We can even upload this extension to the visual studio marketplace.
This fixes a longstanding problem where we didn't support installing
into VS 2017 and higher. In addition to supporting VS 2017, due
to the way this is written we now longer need to do anything special
to support future versions of VS as well. Everything should
"just work". This also fixes several bugs with our old integration,
such as MSBuild triggering full rebuilds when /Zi was used.
Finally, we add a new UI page called "LLVM" which becomes visible
when the LLVM toolchain is selected. For now this only contains
one option which is the path to clang-cl.exe, but in the future
we can add more things here.
[MSan] run materializeChecks() before materializeStores()
When pointer checking is enabled, it's important that every pointer is
checked before its value is used.
For stores MSan used to generate code that calculates shadow/origin
addresses from a pointer before checking it.
For userspace this isn't a problem, because the shadow calculation code
is quite simple and compiler is able to move it after the check on -O2.
But for KMSAN getShadowOriginPtr() creates a runtime call, so we want the
check to be performed strictly before that call.
Swapping materializeChecks() and materializeStores() resolves the issue:
both functions insert code before the given IR location, so the new
insertion order guarantees that the code calculating shadow address is
between the address check and the memory access.
[llvm-objcopy, tests] Fix several llvm-objcopy tests
Summary: In Python 3, sys.stdout.write expects a string rather than bytes. In order to be able to write the bytes to stdout, we need to use the buffer directly instead. This change is borrowing the implementation for writing to stdout that cat.py uses. Note that we cannot use cat.py directly because the file we are trying to open is a gzip file.
Pavel Labath [Fri, 20 Jul 2018 15:24:13 +0000 (15:24 +0000)]
DwarfDebug: Reduce duplication in addAccel*** methods
Summary:
Each of the four methods had a dozen lines and was doing almost exactly
the same thing: get the appropriate accelerator table kind and insert an
entry into it. I move this common logic to a helper function and make
these methods delegate to it.
This came up in the context of D49493, where I've needed to make adding
a string to a string pool slightly more complicated, and it seemed to
make sense to do it in one place instead of five.
To make this work I've needed to unify the interface of the AccelTable
data types, as some used to store DIE& and others DIE*. I chose to unify
to a reference as that's what the caller uses.
This technically isn't NFC, because it changes the StringPool used for
apple tables in the DWO case (now it uses the main file like DWARF v5
instead of the DWO file). However, that shouldn't matter, as DWO is not
a thing on apple targets (clang frontend simply ignores -gsplit-dwarf).
Nirav Dave [Fri, 20 Jul 2018 15:20:50 +0000 (15:20 +0000)]
[DAG] Fix Memory ordering check in ReduceLoadOpStore.
When merging through a TokenFactor we need to check that the
load may be ordered such that no other aliasing memory operations may
happen. It is not sufficient to just check that the load is a member
of the chain token factor as it there may be a indirect chain. Require
the load's chain has only one use.
Recommit r328307: [IPSCCP] Use constant range information for comparisons of parameters.
This version contains a fix to add values for which the state in ParamState change
to the worklist if the state in ValueState did not change. To avoid adding the
same value multiple times, mergeInValue returns true, if it added the value to
the worklist. The value is added to the worklist depending on its state in
ValueState.
Original message:
For comparisons with parameters, we can use the ParamState lattice
elements which also provide constant range information. This improves
the code for PR33253 further and gets us closer to use
ValueLatticeElement for all values.
Also, as we are using the range information in the solver directly, we
do not need tryToReplaceWithConstantRange afterwards anymore.
Simon Pilgrim [Fri, 20 Jul 2018 13:26:51 +0000 (13:26 +0000)]
[X86][AVX] Convert X86ISD::VBROADCAST demanded elts combine to use SimplifyDemandedVectorElts
This is an early step towards using SimplifyDemandedVectorElts for target shuffle combining - this merely moves the existing X86ISD::VBROADCAST simplification code to use the SimplifyDemandedVectorElts mechanism.
Adds X86TargetLowering::SimplifyDemandedVectorEltsForTargetNode to handle X86ISD::VBROADCAST - in time we can support all target shuffles (and other ops) here.
Pavel Labath [Fri, 20 Jul 2018 12:59:05 +0000 (12:59 +0000)]
[DebugInfo] Generate .debug_names section when it makes sense
Summary:
This patch makes us generate the debug_names section in response to some
user-facing commands (previously it was only generated if explicitly
selected via the -accel-tables option).
My goal was to make this work for DWARF>=5 (as it's an official part of
that standard), and also, as an extension, for DWARF<5 if one is
explicitly tuning for lldb as a debugger (because it brings a large
performance improvement there).
This is slightly complicated by the fact that the debug_names tables are
incompatible with the DWARF v4 type units (they assume that the type
units are in the debug_info section), and unfortunately, right now we
generate DWARF v4-style type units even for -gdwarf-5. For this reason,
I disable all accelerator tables if the user requested type unit
generation. I do this even for apple tables, as they have the same
problem (in fact generating type units for apple targets makes us crash
even before we get around to emitting the accelerator tables).
[UBSan] Also use blacklist for 'Address; Undefined' setting
It looks like currently the UBSan blacklist is only applied when "Undefined" is selected.
This patch updates the cmake file to apply it whenever Undefined is selected
(e.g. 'Address; Undefined' ). This allows us to use the workaround added in
rL335525 when using AddressSan and UBSan together.
Jonas Paulsson [Fri, 20 Jul 2018 09:40:43 +0000 (09:40 +0000)]
[SystemZ] Reimplent SchedModel IssueWidth and WriteRes/ReadAdvance mappings.
As a consequence of recent discussions
(http://lists.llvm.org/pipermail/llvm-dev/2018-May/123164.html), this patch
changes the SystemZ SchedModels so that the IssueWidth is 6, which is the
decoder capacity, and NumMicroOps become the number of decoder slots needed
per instruction.
In addition, the SchedWrite latencies now match the MachineInstructions
def-operand indexes, and ReadAdvances have been added on instructions with
one register operand and one memory operand.
The failing bots that had `SmallVector` in the backtrace recovered after
the unrelated commit r337508. The backtraces looked bogus anyway, with
`SmallVector::size()` calling (e.g.) `ConstantArray::get()`.
Here's the original commit message:
ADT: Shrink size of SmallVector by 8B on 64-bit platforms
Represent size and capacity directly as unsigned and calculate
`end()` using `begin() + size()`.
This limits the maximum size/capacity of a vector to UINT32_MAX.
Summary:
lifetime2.C violates DR1696, which prevents reference members from being
initialized to temporaries, whose lifetime would end at the end of ctor.
[x86/SLH] Clean up helper naming for return instruction handling and
remove dead declaration of a call instruction handling helper.
This moves to the 'harden' terminology that I've been trying to settle
on for returns. It also adds a really detailed comment explaining what
all we're trying to accomplish with return instructions and why.
Hopefully this makes it much more clear what exactly is being
"hardened".
Eli Friedman [Thu, 19 Jul 2018 23:02:07 +0000 (23:02 +0000)]
[SCCP] Don't use markForcedConstant on branch conditions.
It's more aggressive than we need to be, and leads to strange
workarounds in other places like call return value inference. Instead,
just directly mark an edge viable.
Teresa Johnson [Thu, 19 Jul 2018 22:25:56 +0000 (22:25 +0000)]
[ThinLTO] Only emit referenced type id records in index files
Summary:
Currently all type ids are emitted into the index file when it is
written. For distributed ThinLTO, that meant that all type ids were
being duplicated into every single distributed index file, regardless of
whether they were referenced, leading to huge amounts of unnecessary
duplication and size bloat.
Keep track of the type id GUIDs actually referenced by the GV summary
records being emitted, and only emit those type IDs.
Add a new test, and fix test/Assembler/thinlto-summary.ll so that all
type ids are referenced to prevent deletion in that test.
Simon Pilgrim [Thu, 19 Jul 2018 21:52:06 +0000 (21:52 +0000)]
[X86][AVX] Use extract_subvector to reduce vector op widths (PR36761)
We have a number of cases where we fail to reduce vector op widths, performing the op in a larger vector and then extracting a subvector. This is often because by default it would create illegal types.
This peephole patch attempts to handle a few common cases detailed in PR36761, which typically involved extension+conversion to vX2f64 types.
Matt Davis [Thu, 19 Jul 2018 20:33:59 +0000 (20:33 +0000)]
[llvm-mca][docs] Add Timeline and How MCA works.
For the most part, these changes were from the RFC. I made a few minor
word/structure changes, but nothing significant. I also regenerated the
example output, and adjusted the text accordingly.
This particular version of GCC seems to break bitfields when a method
appears between two bitfield members.
Personally, I think it's nice to keep bitfields close together so that
it's easy to check how things are packed, so I moved the method after
SubClassData.
It fires on things like SmallVector<std::pair<int, int>>, where we
intentionally use memcpy instead of calling the assignment operator.
This warning fires in practically every LLVM TU, so we have to do
something about it, even if we aren't interested in being 100% warning
clean with GCC.
[X86] Fix some 'return SDValue()' after DCI.CombineTo instead return the output of CombineTo
Returning SDValue() means nothing was changed. Returning the result of CombineTo returns the first argument of CombineTo. This is specially detected by DAGCombiner as meaning that something changed, but worklist management was already taken care of.
I think the only real effect of this change is that we now properly update the Statistic the counts the number of combines performed. That's the only thing between the check for null and the check for N in the DAGCombiner.
Roman Tereshin [Thu, 19 Jul 2018 19:42:43 +0000 (19:42 +0000)]
[LSV] Refactoring + supporting bitcasts to a type of different size
This is mostly a preparation work for adding a limited support for
select instructions. It proved to be difficult to do due to size and
irregularity of Vectorizer::isConsecutiveAccess, this is fixed here I
believe.
It also turned out that these changes make it simpler to finish one of
the TODOs and fix a number of other small issues, namely:
1. Looking through bitcasts to a type of a different size (requires
careful tracking of the original load/store size and some math
converting sizes in bytes to expected differences in indices of GEPs).
2. Reusing partial analysis of pointers done by first attempt in proving
them consecutive instead of starting from scratch. This added limited
support for nested GEPs co-existing with difficult sext/zext
instructions. This also required a careful handling of negative
differences between constant parts of offsets.
3. Handing a case where the first pointer index is not an add, but
something else (a function parameter for instance).
I observe an increased number of successful vectorizations on a large
set of shader programs. Only few shaders are affected, but those that
are affected sport >5% less loads and stores than before the patch.
As we already return true from needsAggressiveScheduling() for the most recent
hardware it would be cleaner to just return true for all PowerPC hardware.
[APInt] Keep the original bit width in quotient and remainder
Some trivial cases in udivrem were handled by directly assigning 0 or 1
to APInt objects. This would set the bit width to 1, instead of the bit
width of the inputs. A potentially undesirable side effect of that is
that with the bit width of 1, 1 equals -1.
[LoadStoreVectorizer] Use getMinusScev() to compute the distance between two pointers.
Summary: Currently, isConsecutiveAccess() detects two pointers(PtrA and PtrB) as consecutive by
comparing PtrB with BaseDelta+PtrA. This works when both pointers are factorized or
both of them are not factorized. But isConsecutiveAccess() fails if one of the
pointers is factorized but the other one is not.
Here is an example:
PtrA = 4 * (A + B)
PtrB = 4 + 4A + 4B
This patch uses getMinusSCEV() to compute the distance between two pointers.
getMinusSCEV() allows combining the expressions and computing the simplified distance.
Andrea Di Biagio [Thu, 19 Jul 2018 16:42:15 +0000 (16:42 +0000)]
[X86][BtVer2] correctly model the latency/throughput of LEA instructions.
This patch fixes the latency/throughput of LEA instructions in the BtVer2
scheduling model.
On Jaguar, A 3-operands LEA has a latency of 2cy, and a reciprocal throughput of
1. That is because it uses one cycle of SAGU followed by 1cy of ALU1. An LEA
with a "Scale" operand is also slow, and it has the same latency profile as the
3-operands LEA. An LEA16r has a latency of 3cy, and a throughput of 0.5 (i.e.
RThrouhgput of 2.0).
This patch adds a new TIIPredicate named IsThreeOperandsLEAFn to X86Schedule.td.
The tablegen backend (for instruction-info) expands that definition into this
(file X86GenInstrInfo.inc):
```
static bool isThreeOperandsLEA(const MachineInstr &MI) {
return (
(
MI.getOpcode() == X86::LEA32r
|| MI.getOpcode() == X86::LEA64r
|| MI.getOpcode() == X86::LEA64_32r
|| MI.getOpcode() == X86::LEA16r
)
&& MI.getOperand(1).isReg()
&& MI.getOperand(1).getReg() != 0
&& MI.getOperand(3).isReg()
&& MI.getOperand(3).getReg() != 0
&& (
(
MI.getOperand(4).isImm()
&& MI.getOperand(4).getImm() != 0
)
|| (MI.getOperand(4).isGlobal())
)
);
}
```
A similar method is generated in the X86_MC namespace, and included into
X86MCTargetDesc.cpp (the declaration lives in X86MCTargetDesc.h).
Back to the BtVer2 scheduling model:
A new scheduling predicate named JSlowLEAPredicate now checks if either the
instruction is a three-operands LEA, or it is an LEA with a Scale value
different than 1.
A variant scheduling class uses that new predicate to correctly select the
appropriate latency profile.
Teresa Johnson [Thu, 19 Jul 2018 14:51:32 +0000 (14:51 +0000)]
[ThinLTO] Enable ThinLTO WholeProgramDevirt and LowerTypeTests in new PM
Summary:
Enable these passes for CFI and WPD in ThinLTO and LTO with the new pass
manager. Add a couple of tests for both PMs based on the clang tests
tools/clang/test/CodeGen/thinlto-distributed-cfi*.ll, but just test
through llvm-lto2 and not with distributed ThinLTO.
[x86/SLH] Major refactoring of SLH implementaiton. There are two big
changes that are intertwined here:
1) Extracting the tracing of predicate state through the CFG to its own
function.
2) Creating a struct to manage the predicate state used throughout the
pass.
Doing #1 necessitates and motivates the particular approach for #2 as
now the predicate management is spread across different functions
focused on different aspects of it. A number of simplifications then
fell out as a direct consequence.
I went with an Optional to make it more natural to construct the
MachineSSAUpdater object.
This is probably the single largest outstanding refactoring step I have.
Things get a bit more surgical from here. My current goal, beyond
generally making this maintainable long-term, is to implement several
improvements to how we do interprocedural tracking of predicate state.
But I don't want to do that until the predicate state management and
tracing is in reasonably clear state.
Max Kazantsev [Thu, 19 Jul 2018 01:46:21 +0000 (01:46 +0000)]
[SCEV] Fix buggy behavior in getAddExpr with truncs
SCEV tries to constant-fold arguments of trunc operands in SCEVAddExpr, and when it does
that, it passes wrong flags into the recursion. It is only valid to pass flags that are proved for
narrow type into a computation in wider type if we can prove that trunc instruction doesn't
actually change the value. If it did lose some meaningful bits, we may end up proving wrong
no-wrap flags for sum of arguments of trunc.
In the provided test we end up with `nuw` where it shouldn't be because of this bug.
The solution is to conservatively pass `SCEV::FlagAnyWrap` which is always a valid thing to do.
This prevents gold from printing a warning when trying to export
these symbols via the asan dynamic list after ThinLTO promotes them
from private symbols to external symbols with hidden visibility.
David Blaikie [Wed, 18 Jul 2018 18:04:42 +0000 (18:04 +0000)]
[DebugInfo] Dwarfv5: Avoid unnecessary base_address specifiers in rnglists
Since DWARFv5 rnglists are self descriptive and have distinct encodings
for base-relative (offset_pair) and absolute (start_length) entries,
there's no need to use a base address specifier when describing a lone
address range in a section.
Use that, and improve the test coverage a bit here to include cases like
this and others.
Nirav Dave [Wed, 18 Jul 2018 18:01:03 +0000 (18:01 +0000)]
[ScheduleDAG] Fix unfolding of SUnits to already existent nodes.
Summary:
If unfolding an SUnit results in both load or the operation using it which
already exist in the DAG, abort the unfold if they are already scheduled.
If not, make sure we don't add duplicate dependencies.
Teresa Johnson [Wed, 18 Jul 2018 17:10:17 +0000 (17:10 +0000)]
[docs] Update GoldPlugin documentation
Summary:
Updated and reorganized. Made the following additions:
1) How to see if ld.gold is installed, and whether it is the current
default.
2) How to install ld.gold as the default or alternatively use
-fuse-ld=gold.
3) Move the part about installing the newly built ld-new as the default
to the prior section and how to use --enable-gold=default to do it
automatically on install.
4) Add a note about ld.bfd supporting plugins but indicate that it is
not tested by the LLVM project and gold is the recommended linker for
use with the gold plugin.