Dan Gohman [Tue, 28 Nov 2017 17:15:03 +0000 (17:15 +0000)]
[WebAssembly] Support bitcasted function addresses with varargs.
Generalize FixFunctionBitcasts to handle varargs functions. This in
particular fixes the case where clang bitcasts away a varargs when
calling a K&R-style function.
This avoids interacting with tricky ABI details because it operates
at the LLVM IR level before varargs ABI details are exposed.
Don Hinton [Tue, 28 Nov 2017 16:08:57 +0000 (16:08 +0000)]
[cmake] Remove redundant call to cmake when building host tools.
Summary:
Remove the redundant, config-time call to cmake when
building host tools for cross compiles or optimized tablegen..
The config-time call to cmake is redundant because it will always get
called again when the CONFIGURE_LLVM_${target_name} target fires at
build-time. This speeds up initial configuration, but has no affect
on build behavior.
Jonas Paulsson [Tue, 28 Nov 2017 14:44:32 +0000 (14:44 +0000)]
Use getStoreSize() in various places instead of 'BitSize >> 3'.
This is needed for cases when the memory access is not as big as the width of
the data type. For instance, storing i1 (1 bit) would be done in a byte (8
bits).
Using 'BitSize >> 3' (or '/ 8') would e.g. give the memory access of an i1 a
size of 0, which for instance makes alias analysis return NoAlias even when
it shouldn't.
There are no tests as this was done as a follow-up to the bugfix for the case
where this was discovered (r318824). This handles more similar cases.
Review: Björn Petterson
https://reviews.llvm.org/D40339
LLVM Coding Standards:
Function names should be verb phrases (as they represent actions), and
command-like function should be imperative. The name should be camel
case, and start with a lower case letter (e.g. openFile() or isFoo()).
Peter Smith [Tue, 28 Nov 2017 12:34:05 +0000 (12:34 +0000)]
[ARM][AArch64] Workaround ARM/AArch64 peculiarity in clearing icache.
Certain ARM implementations treat icache clear instruction as a memory read,
and CPU segfaults on trying to clear cache on !PROT_READ page.
We workaround this in Memory::protectMappedMemory by adding
PROT_READ to affected pages, clearing the cache, and then setting
desired protection.
This fixes "AllocationTests/MappedMemoryTest.***/3" unit-tests on
affected hardware.
Chandler Carruth [Tue, 28 Nov 2017 11:32:31 +0000 (11:32 +0000)]
Add a new pass to speculate around PHI nodes with constant (integer) operands when profitable.
The core idea is to (re-)introduce some redundancies where their cost is
hidden by the cost of materializing immediates for constant operands of
PHI nodes. When the cost of the redundancies is covered by this,
avoiding materializing the immediate has numerous benefits:
1) Less register pressure
2) Potential for further folding / combining
3) Potential for more efficient instructions due to immediate operand
As a motivating example, consider the remarkably different cost on x86
of a SHL instruction with an immediate operand versus a register
operand.
This pattern turns up surprisingly frequently, but is somewhat rarely
obvious as a significant performance problem.
The pass is entirely target independent, but it does rely on the target
cost model in TTI to decide when to speculate things around the PHI
node. I've included x86-focused tests, but any target that sets up its
immediate cost model should benefit from this pass.
There is probably more that can be done in this space, but the pass
as-is is enough to get some important performance on our internal
benchmarks, and should be generally performance neutral, but help with
more extensive benchmarking is always welcome.
One awkward part is that this pass has to be scheduled after
*everything* that can eliminate these kinds of redundancies. This
includes SimplifyCFG, GVN, etc. I'm open to suggestions about better
places to put this. We could in theory make it part of the codegen pass
pipeline, but there doesn't really seem to be a good reason for that --
it isn't "lowering" in any sense and only relies on pretty standard cost
model based TTI queries, so it seems to fit well with the "optimization"
pipeline model. Still, further thoughts on the pipeline position are
welcome.
I've also only implemented this in the new pass manager. If folks are
very interested, I can try to add it to the old PM as well, but I didn't
really see much point (my use case is already switched over to the new
PM).
I've tested this pretty heavily without issue. A wide range of
benchmarks internally show no change outside the noise, and I don't see
any significant changes in SPEC either. However, the size class
computation in tcmalloc is substantially improved by this, which turns
into a 2% to 4% win on the hottest path through tcmalloc for us, so
there are definitely important cases where this is going to make
a substantial difference.
Florian Hahn [Tue, 28 Nov 2017 09:32:25 +0000 (09:32 +0000)]
[TailRecursionElimination] Skip debug intrinsics.
Summary:
I think we do not need to analyze debug intrinsics here, as they should
not impact codegen. This has 2 benefits: 1) slightly less work to do and
2) avoiding generating optimization remarks for converting calls to
debug intrinsics to tail calls, which are not really helpful for users.
Nicolai Haehnle [Tue, 28 Nov 2017 08:42:46 +0000 (08:42 +0000)]
AMDGPU: Re-organize the outer loop of SILoadStoreOptimizer
Summary:
The entire algorithm operates per basic-block, so for cache locality
it should be better to re-optimize a basic-block immediately rather than
in a separate loop.
Nicolai Haehnle [Tue, 28 Nov 2017 08:41:50 +0000 (08:41 +0000)]
AMDGPU: Consistently check for immediates in SIInstrInfo::FoldImmediate
Summary:
The PeepholeOptimizer pass calls this function solely based on checking
DefMI->isMoveImmediate(), which only checks the MoveImm bit of the
instruction description. So it's up to FoldImmediate itself to properly
check that DefMI *actually* moves from an immediate.
I don't have a separate test case for this, but the next patch introduces
a test case which happens to crash without this change.
This error is caught by the assertion in MachineOperand::getImm().
Max Kazantsev [Tue, 28 Nov 2017 08:26:43 +0000 (08:26 +0000)]
[SCEV][NFC] More efficient caching in CompareValueComplexity
Currently, we use a set of pairs to cache responces like `CompareValueComplexity(X, Y) == 0`. If we had
proved that `CompareValueComplexity(S1, S2) == 0` and `CompareValueComplexity(S2, S3) == 0`,
this cache does not allow us to prove that `CompareValueComplexity(S1, S3)` is also `0`.
This patch replaces this set with `EquivalenceClasses` that merges Values into equivalence sets so that
any two values from the same set are equal from point of `CompareValueComplexity`. This, in particular,
allows us to prove the fact from example above.
Max Kazantsev [Tue, 28 Nov 2017 07:48:12 +0000 (07:48 +0000)]
[SCEV][NFC] More efficient caching in CompareSCEVComplexity
Currently, we use a set of pairs to cache responces like `CompareSCEVComplexity(X, Y) == 0`. If we had
proved that `CompareSCEVComplexity(S1, S2) == 0` and `CompareSCEVComplexity(S2, S3) == 0`,
this cache does not allow us to prove that `CompareSCEVComplexity(S1, S3)` is also `0`.
This patch replaces this set with `EquivalenceClasses` any two values from the same set are equal from
point of `CompareSCEVComplexity`. This, in particular, allows us to prove the fact from example above.
Max Kazantsev [Tue, 28 Nov 2017 07:07:55 +0000 (07:07 +0000)]
[GVN] Prevent ScalarPRE from hoisting across instructions that don't pass control flow to successors
This is to address a problem similar to those in D37460 for Scalar PRE. We should not
PRE across an instruction that may not pass execution to its successor unless it is safe
to speculatively execute it.
Simon Dardis [Tue, 28 Nov 2017 04:07:59 +0000 (04:07 +0000)]
[DAGCombine] Disable finding better chains for stores at O0
Unoptimized IR can have linear sequences of stores to an array, where the
initial GEP for the first store is formed from the pointer to the array, and the
GEP for each store after the first is formed from the previous GEP with some
offset in an inductive fashion.
The (large) resulting DAG when analyzed by DAGCombine undergoes an excessive
number of combines as each store node is examined every time its' offset node
is combined with any child of the offset. One of the transformations is
findBetterNeighborChains which assists MergeConsecutiveStores. The former
relies on repeated chain walking to do its' work, however MergeConsecutiveStores
is disabled at O0 which makes the transformation redundant.
Any optimization level other than O0 would invoke InstCombine which would
resolve the chain of GEPs into flat base + offset GEP for each store which
does not exhibit the repeated examination of each store to the array.
Disabling this optimization fixes an excessive compile time issue (30~ minutes
for the test case provided) at O0.
Matthias Braun [Tue, 28 Nov 2017 03:54:20 +0000 (03:54 +0000)]
MachineVerifier: Improve register operand checks
This fixes cases where we wouldn't perform various register operand
checks just because we didn't happen to have a definition in the
MCInstrDesc. This changes the code to only skip the tests that actually
depend on the MCInstrDesc definition.
This makes the machine verifier spot the problem from
https://llvm.org/PR33071 after the pass that actually caused it.
Matthias Braun [Tue, 28 Nov 2017 03:54:19 +0000 (03:54 +0000)]
MachineVerifier: Improve PHI operand checking
Additional checks for phi operands:
- first operand should be a virtual register def. It should not be
tied, implicit, internalread, earlyclobber or a read.
- The other operands should be register/mbb operands next to each other
- The register operands should not be implicit, internalread,
earlyclobber, debug or tied.
- We can perform most of the PHI checks even for unreachable blocks.
Reland r319090, "COFF: Do not create SectionChunks for discarded comdat sections." with a fix for debug sections.
If /debug was not specified, readSection will return a null
pointer for debug sections. If the debug section is associative with
another section, we need to make sure that the section returned from
readSection is not a null pointer before adding it as an associative
section.
Dan Gohman [Tue, 28 Nov 2017 01:13:40 +0000 (01:13 +0000)]
[WebAssembly] Fix trapping behavior in fptosi/fptoui.
This adds code to protect WebAssembly's `trunc_s` family of opcodes
from values outside their domain. Even though such conversions have
full undefined behavior in C/C++, LLVM IR's `fptosi` and `fptoui` do
not, and only return undef.
This also implements the proposed non-trapping float-to-int conversion
feature and uses that instead when available.
Craig Topper [Mon, 27 Nov 2017 22:56:10 +0000 (22:56 +0000)]
[X86] Teach getSetCCResultType to handle more than just SimpleVTs when looking at larger than 512-bit vectors.
Which VTs are considered simple is determined by the superset of the legal types of all targets in LLVM. If we're looking at VTs that are going to be split down to 512-bits we should allow any VT not just simple ones since the simple list changes over time as new targets are added.
Petr Hosek [Mon, 27 Nov 2017 22:31:11 +0000 (22:31 +0000)]
[CMake][runtimes] Support monorepo layout with runtimes build
We introduce a new variable LLVM_ENABLE_RUNTIMES which works
similarly to LLVM_ENABLE_PROJECTS and allows specifying runtimes
that will be enabled in the runtimes build.
Michal Gorny [Mon, 27 Nov 2017 22:23:09 +0000 (22:23 +0000)]
[cmake] Pass -Wl,-z,nodelete on Linux to prevent unloading
Prevent unloading shared libraries on Linux when dlclose() is called.
This is necessary since command-line option parsing API relies on
registering the global option instances in the option parser instance
which can be loaded in a different shared library.
Given that we can't reliably remove those options when a library is
unloaded, the parser ends up containing dangling references. Since glibc
has relatively complex library unloading rules, some of the LLVM
libraries can be unloaded while others (including the Support library)
stay loaded causing quite a mayhem. To reliably prevent that, just
forbid unloading all libraries -- it's a very bad idea anyway.
While the issue arguably happens only with BUILD_SHARED_LIBS, it may
affect any library reusing llvm::cl interface.
Based on patch provided Ross Hayward on https://bugs.gentoo.org/617154.
Previously hit by Fedora back in Feb 2016:
https://lists.freedesktop.org/archives/mesa-dev/2016-February/107242.html
Greg Clayton [Mon, 27 Nov 2017 22:12:44 +0000 (22:12 +0000)]
Fixed the ability to recursively get an attribute value from a DWARFDie.
The previous implementation would only look 1 DW_AT_specification or DW_AT_abstract_origin deep. This means DWARFDie::getName() would fail in certain cases. I ran into such a case while creating a tool that used the LLVM DWARF parser to generate a symbolication format so I have seen this in the wild.
Craig Topper [Mon, 27 Nov 2017 22:01:17 +0000 (22:01 +0000)]
[X86] Remove lines that set v8f32 FP_ROUND/FP_EXTEND to Legal under AVX512. NFCI
We don't do this for narrow vectors under AVX or SSE features. We also don't set them to Expand like we do for many vectors op. Nor does TargetLoweringBase.cpp. This leads me to believe these default to Legal.
Davide Italiano [Mon, 27 Nov 2017 21:25:13 +0000 (21:25 +0000)]
[SROA] Propagate !range metadata when moving loads.
This tries to propagate !range metadata to a pre-existing load
when a load is optimized out. This is done instead of adding an
assume because converting loads to and from assumes creates a
lot of IR.
COFF: Do not create SectionChunks for discarded comdat sections.
With this change, instead of creating a SectionChunk for each section
in the object file, we only create them when we encounter a prevailing
comdat section.
Also change how symbol resolution occurs between comdat symbols. Now
only the comdat leader participates in comdat resolution, and not any
other external associated symbols. This is more in line with how COFF
semantics are defined, and should allow for a more straightforward
implementation of non-ANY comdat types.
On my machine, this change reduces our runtime linking a release
build of chrome_child.dll with /nopdb from 5.65s to 4.54s (median of
50 runs).
Petr Hosek [Mon, 27 Nov 2017 20:41:53 +0000 (20:41 +0000)]
Use LIST_SEPARATOR rather than escaping in ExternalProject_Add
Escaping ; in list arguments passed to ExternalProject_Add doesn't seem
to be working in newer versions of CMake (see
https://public.kitware.com/Bug/view.php?id=16137 for more details). Use
a custom LIST_SEPARATOR instead which is the officially supported way.
Zaara Syeda [Mon, 27 Nov 2017 20:26:36 +0000 (20:26 +0000)]
[PowerPC] Remove redundant TOC saves
This patch adds a peep hole optimization to remove any redundant toc save
instructions added as part of the call sequence for indirect calls. It removes
any toc saves within a function that are dominated by another toc save.
David Blaikie [Mon, 27 Nov 2017 19:43:58 +0000 (19:43 +0000)]
Rename CommandFlags.h -> CommandFlags.def
Since this isn't a real header - it includes static functions and had
external linkage variables (though this change makes them static, since
that's what they should be) so can't be included more than once in a
program.
Jake Ehrlich [Mon, 27 Nov 2017 18:56:01 +0000 (18:56 +0000)]
[llvm-objcopy] Add --strip-all-gnu and change --strip-all
GNU's --strip-all doesn't strip as aggressively as it could in general.
Currently llvm-objcopy copies the exact behavoir of GNU's --strip-all.
eu-strip is used as a drop in replacement for GNU strip/objcopy in many many
places without issue. eu-strip removes non-allocated sections and keeps
.gnu.warning* sections. Because --strip-all will likely be the most widely
used stripping option we should make --strip-all as aggressive as it can safely
be. Since we have evidence from eu-strip that this is a safe option we should
allow it. For those that might still have an issue afterwards I've added
--strip-all-gnu as an exact drop in replacement for GNU's --strip-all as well.
Zachary Turner [Mon, 27 Nov 2017 18:48:37 +0000 (18:48 +0000)]
[BinaryStream] Support growable streams.
The existing library assumed that a stream's length would never
change. This makes some things simpler, but it's not flexible
enough for what we need, especially for writable streams where
what you really want is for each call to write to actually append.
Michal Gorny [Mon, 27 Nov 2017 18:34:52 +0000 (18:34 +0000)]
[cmake] Pass -Wl,-z,nodelete on Linux to prevent unloading
Prevent unloading shared libraries on Linux when dlclose() is called.
This is necessary since command-line option parsing API relies on
registering the global option instances in the option parser instance
which can be loaded in a different shared library.
Given that we can't reliably remove those options when a library is
unloaded, the parser ends up containing dangling references. Since glibc
has relatively complex library unloading rules, some of the LLVM
libraries can be unloaded while others (including the Support library)
stay loaded causing quite a mayhem. To reliably prevent that, just
forbid unloading all libraries -- it's a very bad idea anyway.
While the issue arguably happens only with BUILD_SHARED_LIBS, it may
affect any library reusing llvm::cl interface.
Based on patch provided Ross Hayward on https://bugs.gentoo.org/617154.
Previously hit by Fedora back in Feb 2016:
https://lists.freedesktop.org/archives/mesa-dev/2016-February/107242.html
Craig Topper [Mon, 27 Nov 2017 18:15:14 +0000 (18:15 +0000)]
[X86] Teach combineX86ShuffleChain that AllowIntDomain requires at least SSE2.
I don't have a good test case for this at the moment. I was playing around with a change in legalizing and triggered this code to produce a PSHUFD with sse1 only.
Craig Topper [Mon, 27 Nov 2017 17:51:55 +0000 (17:51 +0000)]
[X86] Make getSetCCResultType return vXi1 for any vXi32/vXi64 vector over 512 bits long when AVX512 is enabled.
Similar for vXi16/vXi8 with BWI.
Any vector larger than 512 bits will be split to 512 bits during legalization. But without this we will fold sexts with them before that making it difficult to recover leading to scalarization.
Zaara Syeda [Mon, 27 Nov 2017 17:11:03 +0000 (17:11 +0000)]
[Power9] Improvements to vector extract with variable index exploitation
This patch extends on to rL307174 to not use the power9 vector extract with
variable index instructions when extracting word element 1. For such cases,
the existing selection of MFVSRWZ provides a better sequence.
[llvm-dwarfdump] Display DW_AT_high_pc as absolute value
DWARF4 relative DW_AT_high_pc values are now displayed as absolute
addresses. The relative value is only shown when explicitly dumping the
forms, i.e. in show-form or verbose mode.
Nirav Dave [Mon, 27 Nov 2017 15:28:15 +0000 (15:28 +0000)]
[DAG] Do MergeConsecutiveStores again before Instruction Selection
Summary:
Now that store-merge is only generates type-safe stores, do a second
pass just before instruction selection to allow lowered intrinsics to
be merged as well.
Petar Jovanovic [Mon, 27 Nov 2017 14:25:36 +0000 (14:25 +0000)]
[mips] fix asmstring of Ext and Ins instructions and mips16 JALRC/JRC
Make the print format consistent with other assembler instructions.
Adding a tab character instead of space in asmstring of Ext and Ins
instructions.
Removing space around the tab character for JALRC and replacing space with
tab in JRC.
Vedran Miletic [Mon, 27 Nov 2017 13:26:38 +0000 (13:26 +0000)]
[AMDGPU] Add custom lowering for llvm.log{,10}.{f16,f32} intrinsics
AMDGPU backend errors with "unsupported call to function" upon
encountering a call to llvm.log{,10}.{f16,f32} intrinsics. This patch
adds custom lowering to avoid that error on both R600 and SI.
John Brawn [Mon, 27 Nov 2017 11:29:15 +0000 (11:29 +0000)]
[CGP] Fix handling of null pointer values in optimizeMemoryInst
The current way that trivial addressing modes are detected incorrectly thinks
that null pointers are non-trivial, leading to an infinite loop where we keep
duplicating the same select. Fix this by aware of null when deciding if an
addressing mode is trivial.