Commit Graph

4578 Commits

Author SHA1 Message Date
Jay Foad e20efa3dd5 [LegacyPM] Simplify PMTopLevelManager::collectLastUses. NFC. 2020-11-30 10:36:19 +00:00
Nikita Popov 891170e863 [DL] Optimize address space zero lookup (NFC)
Information for pointer size/alignment/etc is queried a lot, but
the binary search based implementation makes this fairly slow.

Add an explicit check for address space zero and skip the search
in that case -- we need to specially handle the zero address space
anyway, as it serves as the fallback for all address spaces that
were not explicitly defined.

I initially wanted to simply replace the binary search with a
linear search, which would handle both address space zero and the
general case efficiently, but I was not sure whether there are
any degenerate targets that use more than a handful of declared
address spaces (in-tree, even AMDGPU only declares six).
2020-11-29 22:49:55 +01:00
Sanjay Patel ce134da4b1 [IR] simplify code in removePredecessor(); NFCI
As suggested in D92247 (and independent of whatever we decide to do there),
this code is confusing as-is. Hopefully, this is at least mildly better.

We might be able to do better still, but we have a function called
"removePredecessor" with this behavior:
"Note that this function does not actually remove the predecessor." (!)
2020-11-29 09:55:04 -05:00
Sanjay Patel 2cebad702c [IR] remove redundant code comments; NFC
As noted in D92247 (and independent of that patch):

http://llvm.org/docs/CodingStandards.html#doxygen-use-in-documentation-comments

"Don’t duplicate the documentation comment in the header file and in the
implementation file. Put the documentation comments for public APIs into
the header file."
2020-11-29 09:29:59 -05:00
Juneyoung Lee 53040a968d [ConstantFold] Fold more operations to poison
This patch folds more operations to poison.

Alive2 proof: https://alive2.llvm.org/ce/z/mxcb9G (it does not contain tests about div/rem because they fold to poison when raising UB)

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D92270
2020-11-29 21:19:48 +09:00
Juneyoung Lee c6b62efb91 [ConstantFold] Fold operations to poison if possible
This patch updates ConstantFold, so operations are folded into poison if possible.

<alive2 proofs>
casts: https://alive2.llvm.org/ce/z/WSj7rw
binary operations (arithmetic): https://alive2.llvm.org/ce/z/_7dEyJ
binary operations (bitwise): https://alive2.llvm.org/ce/z/cezjVN
vector/aggregate operations: https://alive2.llvm.org/ce/z/BQ7hWz
unary ops: https://alive2.llvm.org/ce/z/yBRs4q
other ops: https://alive2.llvm.org/ce/z/iXbcFD

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D92203
2020-11-29 02:28:40 +09:00
Francesco Petrogalli 8e0148dff7 [AllocaInst] Update `getAllocationSizeInBits` to return `TypeSize`.
Reviewed By: peterwaller-arm, sdesmalen

Differential Revision: https://reviews.llvm.org/D92020
2020-11-27 16:39:10 +00:00
Jay Foad 68ed644785 [LegacyPM] Avoid a redundant map lookup in setLastUser. NFC.
As a bonus this makes it (IMO) obvious that the iterator is not
invalidated, so remove the comment explaining that.
2020-11-27 10:42:01 +00:00
Jay Foad 0d9166ff79 [LegacyPM] Remove unused undocumented parameter. NFC.
The Direction parameter to AnalysisResolver::getAnalysisIfAvailable has
never been documented or used for anything.
2020-11-27 10:41:38 +00:00
Zhengyang Liu 345fcccb33 Fix use-of-uninitialized-value in rG75f50e15bf8f
Differential Revision: https://reviews.llvm.org/D71126
2020-11-26 01:39:22 -07:00
Zhengyang Liu 75f50e15bf Adding PoisonValue for representing poison value explicitly in IR
Define ConstantData::PoisonValue.
Add support for poison value to LLLexer/LLParser/BitcodeReader/BitcodeWriter.
Add support for poison value to llvm-c interface.
Add support for poison value to OCaml binding.
Add m_Poison in PatternMatch.

Differential Revision: https://reviews.llvm.org/D71126
2020-11-25 17:33:51 -07:00
Arthur Eubanks 3d1149c6fe Make CallInst::updateProfWeight emit i32 weights instead of i64
Typically branch_weights are i32, not i64.
This fixes entry_counts_cold.ll under NPM.

Reviewed By: asbirlea

Differential Revision: https://reviews.llvm.org/D90539
2020-11-24 18:13:59 -08:00
Simon Pilgrim 49e463ff80 [IR] Constant::getAggregateElement - early-out for ScalableVectorType
We can't call getNumElements() for ScalableVectorType types - just bail for now, although ConstantAggregateZero/UndefValue could return a reasonable value.

Fixes crash shown in OSS-Fuzz #25272 https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=25272
2020-11-24 12:03:27 +00:00
Matt Arsenault 650fbd569a Verifier: Fix assert when verifying non-pointer byval or preallocated
This would fail on a cast<PointerType> when verifying the attribute if
these attributes were incorrectly used with a non-pointer type.
2020-11-20 20:08:43 -05:00
Hongtao Yu f3c445697d [CSSPGO] IR intrinsic for pseudo-probe block instrumentation
This change introduces a new IR intrinsic named `llvm.pseudoprobe` for pseudo-probe block instrumentation. Please refer to https://reviews.llvm.org/D86193 for the whole story.

A pseudo probe is used to collect the execution count of the block where the probe is instrumented. This requires a pseudo probe to be persisting. The LLVM PGO instrumentation also instruments in similar places by placing a counter in the form of atomic read/write operations or runtime helper calls. While these operations are very persisting or optimization-resilient, in theory we can borrow the atomic read/write implementation from PGO counters and cut it off at the end of compilation with all the atomics converted into binary data. This was our initial design and we’ve seen promising sample correlation quality with it. However, the atomics approach has a couple issues:

1. IR Optimizations are blocked unexpectedly. Those atomic instructions are not going to be physically present in the binary code, but since they are on the IR till very end of compilation, they can still prevent certain IR optimizations and result in lower code quality.
2. The counter atomics may not be fully cleaned up from the code stream eventually.
3. Extra work is needed for re-targeting.

We choose to implement pseudo probes based on a special LLVM intrinsic, which is expected to have most of the semantics that comes with an atomic operation but does not block desired optimizations as much as possible. More specifically the semantics associated with the new intrinsic enforces a pseudo probe to be virtually executed exactly the same number of times before and after an IR optimization. The intrinsic also comes with certain flags that are carefully chosen so that the places they are probing are not going to be messed up by the optimizer while most of the IR optimizations still work. The core flags given to the special intrinsic is `IntrInaccessibleMemOnly`, which means the intrinsic accesses memory and does have a side effect so that it is not removable, but is does not access memory locations that are accessible by any original instructions. This way the intrinsic does not alias with any original instruction and thus it does not block optimizations as much as an atomic operation does. We also assign a function GUID and a block index to an intrinsic so that they are uniquely identified and not merged in order to achieve good correlation quality.

Let's now look at an example. Given the following LLVM IR:

```
define internal void @foo2(i32 %x, void (i32)* %f) !dbg !4 {
bb0:
  %cmp = icmp eq i32 %x, 0
   br i1 %cmp, label %bb1, label %bb2
bb1:
   br label %bb3
bb2:
   br label %bb3
bb3:
   ret void
}
```

The instrumented IR will look like below. Note that each `llvm.pseudoprobe` intrinsic call represents a pseudo probe at a block, of which the first parameter is the GUID of the probe’s owner function and the second parameter is the probe’s ID.

```
define internal void @foo2(i32 %x, void (i32)* %f) !dbg !4 {
bb0:
   %cmp = icmp eq i32 %x, 0
   call void @llvm.pseudoprobe(i64 837061429793323041, i64 1)
   br i1 %cmp, label %bb1, label %bb2
bb1:
   call void @llvm.pseudoprobe(i64 837061429793323041, i64 2)
   br label %bb3
bb2:
   call void @llvm.pseudoprobe(i64 837061429793323041, i64 3)
   br label %bb3
bb3:
   call void @llvm.pseudoprobe(i64 837061429793323041, i64 4)
   ret void
}

```

Reviewed By: wmi

Differential Revision: https://reviews.llvm.org/D86490
2020-11-20 10:39:24 -08:00
Alex Richardson 51e09e1d5a [AMDGPU] Set the default globals address space to 1
This will ensure that passes that add new global variables will create them
in address space 1 once the passes have been updated to no longer default
to the implicit address space zero.
This also changes AutoUpgrade.cpp to add -G1 to the DataLayout if it wasn't
already to present to ensure bitcode backwards compatibility.

Reviewed by: arsenm

Differential Revision: https://reviews.llvm.org/D84345
2020-11-20 15:46:53 +00:00
Alex Richardson 3bc4157556 Add a default address space for globals to DataLayout
This is similar to the existing alloca and program address spaces (D37052)
and should be used when creating/accessing global variables.
We need this in our CHERI fork of LLVM to place all globals in address space 200.
This ensures that values are accessed using CHERI load/store instructions
instead of the normal MIPS/RISC-V ones.

The problem this is trying to fix is that most of the time the type of
globals is created using a simple PointerType::getUnqual() (or ::get() with
the default address-space value of 0). This does not work for us and we get
assertion/compilation/instruction selection failures whenever a new call
is added that uses the default value of zero.

In our fork we have removed the default parameter value of zero for most
address space arguments and use DL.getProgramAddressSpace() or
DL.getGlobalsAddressSpace() whenever possible. If this change is accepted,
I will upstream follow-up patches to use DL.getGlobalsAddressSpace() instead
of relying on the default value of 0 for PointerType::get(), etc.

This patch and the follow-up changes will not have any functional changes
for existing backends with the default globals address space of zero.
A follow-up commit will change the default globals address space for
AMDGPU to 1.

Reviewed By: dylanmckay

Differential Revision: https://reviews.llvm.org/D70947
2020-11-20 15:46:52 +00:00
Leonard Chan a97f62837f [llvm][IR] Add dso_local_equivalent Constant
The `dso_local_equivalent` constant is a wrapper for functions that represents a
value which is functionally equivalent to the global passed to this. That is, if
this accepts a function, calling this constant should have the same effects as
calling the function directly. This could be a direct reference to the function,
the `@plt` modifier on X86/AArch64, a thunk, or anything that's equivalent to the
resolved function as a call target.

When lowered, the returned address must have a constant offset at link time from
some other symbol defined within the same binary. The address of this value is
also insignificant. The name is leveraged from `dso_local` where use of a function
or variable is resolved to a symbol in the same linkage unit.

In this patch:
- Addition of `dso_local_equivalent` and handling it
- Update Constant::needsRelocation() to strip constant inbound GEPs and take
  advantage of `dso_local_equivalent` for relative references

This is useful for the [Relative VTables C++ ABI](https://reviews.llvm.org/D72959)
which makes vtables readonly. This works by replacing the dynamic relocations for
function pointers in them with static relocations that represent the offset between
the vtable and virtual functions. If a function is externally defined,
`dso_local_equivalent` can be used as a generic wrapper for the function to still
allow for this static offset calculation to be done.

See [RFC](http://lists.llvm.org/pipermail/llvm-dev/2020-August/144469.html) for more details.

Differential Revision: https://reviews.llvm.org/D77248
2020-11-19 10:26:17 -08:00
Nick Desaulniers f4c6080ab8 Revert "[IR] add fn attr for no_stack_protector; prevent inlining on mismatch"
This reverts commit b7926ce6d7.

Going with a simpler approach.
2020-11-17 17:27:14 -08:00
Christopher Tetreault 792f8e1114 [SVE] Take constant fold fast path for splatted vscale vectors
This should be a perfectly reasonable operation for scalable vectors.
Currently, it only works for zeroinitializer values of
ScalableVectorType, but the fundamental operation is sound and it should
be possible to make it work for other splats

Reviewed By: david-arm

Differential Revision: https://reviews.llvm.org/D77442
2020-11-17 12:45:31 -08:00
Simon Pilgrim 7e30989dab [IR] ShuffleVectorInst::isIdentityWithPadding - bail on non-fixed-type vector shuffles.
Fixes https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=27416
2020-11-17 16:16:51 +00:00
Arthur Eubanks 7de6dcd246 [Debugify] Skip debugifying on special/immutable passes
With a function pass manager, it would insert debuginfo metadata before
getting to function passes while processing the pass manager, causing
debugify to skip while running the function passes.

Skip special passes + verifier + printing passes. Compared to the legacy
implementation of -debugify-each, this additionally skips verifier
passes. Probably no need to update the legacy version since it will be
obsolete soon.

This fixes 2 instcombine tests using -debugify-each under NPM.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D91558
2020-11-16 20:39:46 -08:00
Florian Hahn ca2e7e5999 [IRGen] Add !annotation metadata for auto-init stores.
This patch updates Clang's IRGen to add !annotation nodes with an
"auto-init" annotation to all stores for auto-initialization.

As discussed in 'RFC: Combining Annotation Metadata and Remarks'
(http://lists.llvm.org/pipermail/llvm-dev/2020-November/146393.html)
this allows using optimization remarks to track down where auto-init
code was inserted (and not removed by optimizations).

There are a few cases in the tests where !annotation gets dropped by
optimizations. Those optimizations will be updated in subsequent
patches.

This patch is based on a patch by Francis Visoiu Mistrih.

Reviewed By: thegameg, paquette

Differential Revision: https://reviews.llvm.org/D91417
2020-11-16 10:37:02 +00:00
Simon Moll 0007d8ed2c [VP][NFC] Rename to HANDLE_VP_TO_OPC
Use the less surprising shorthand OPC instead of OC.
2020-11-16 10:24:18 +01:00
Kazu Hirata aa06951377 [IR] Use llvm::is_contained in BasicBlock::removePredecessor (NFC) 2020-11-15 21:15:31 -08:00
Roman Lebedev 6861d938e5
Revert "clang-misexpect: Profile Guided Validation of Performance Annotations in LLVM"
See discussion in https://bugs.llvm.org/show_bug.cgi?id=45073 / https://reviews.llvm.org/D66324#2334485
the implementation is known-broken for certain inputs,
the bugreport was up for a significant amount of timer,
and there has been no activity to address it.
Therefore, just completely rip out all of misexpect handling.

I suspect, fixing it requires redesigning the internals of MD_misexpect.
Should anyone commit to fixing the implementation problem,
starting from clean slate may be better anyways.

This reverts commit 7bdad08429,
and some of it's follow-ups, that don't stand on their own.
2020-11-14 13:12:38 +03:00
Yuanfang Chen a223354161 [CGProfile] allows bitcast in metadata node storing function pointers
For example,  during RAUW in IRMover, the `Function` ValueAsMetadata in "CG Profile" could become bitcast.

Reviewed By: tejohnson

Differential Revision: https://reviews.llvm.org/D88433
2020-11-13 09:28:21 -08:00
Florian Hahn 8bb6347939
Add !annotation metadata and remarks pass.
This patch adds a new !annotation metadata kind which can be used to
attach annotation strings to instructions.

It also adds a new pass that emits summary remarks per function with the
counts for each annotation kind.

The intended uses cases for this new metadata is annotating
'interesting' instructions and the remarks should provide additional
insight into transformations applied to a program.

To motivate this, consider these specific questions we would like to get answered:

* How many stores added for automatic variable initialization remain after optimizations? Where are they?
* How many runtime checks inserted by a frontend could be eliminated? Where are the ones that did not get eliminated?

Discussed on llvm-dev as part of 'RFC: Combining Annotation Metadata and Remarks'
(http://lists.llvm.org/pipermail/llvm-dev/2020-November/146393.html)

Reviewed By: thegameg, jdoerfert

Differential Revision: https://reviews.llvm.org/D91188
2020-11-13 13:24:10 +00:00
serge-sans-paille 9218ff50f9 llvmbuildectomy - replace llvm-build by plain cmake
No longer rely on an external tool to build the llvm component layout.

Instead, leverage the existing `add_llvm_componentlibrary` cmake function and
introduce `add_llvm_component_group` to accurately describe component behavior.

These function store extra properties in the created targets. These properties
are processed once all components are defined to resolve library dependencies
and produce the header expected by llvm-config.

Differential Revision: https://reviews.llvm.org/D90848
2020-11-13 10:35:24 +01:00
Kazushi (Jam) Marukawa 410626c9b5 [VE] Support vld intrinsics
Add intrinsics for vector load instructions.  Add a regression test also.

Reviewed By: simoll

Differential Revision: https://reviews.llvm.org/D91332
2020-11-13 07:34:42 +09:00
Sebastian Neubauer a022b1ccd8 [AMDGPU] Add amdgpu_gfx calling convention
Add a calling convention called amdgpu_gfx for real function calls
within graphics shaders. For the moment, this uses the same calling
convention as other calls in amdgpu, with registers excluded for return
address, stack pointer and stack buffer descriptor.

Differential Revision: https://reviews.llvm.org/D88540
2020-11-09 16:51:44 +01:00
Roman Lebedev 8d0fdd36a3
[IR] CmpInst: Add getFlippedSignednessPredicate()
And refactor a few places to use it
2020-11-06 11:31:09 +03:00
Roman Lebedev c7c702a272
[IR] CmpInst: add isEquality(Pred)
Currently there is only a member version of isEquality(),
which requires an actual [IF]CmpInst to be avaliable,
which isn't always possible, and is inconsistent with
the general pattern here.

I wanted to use it in a new patch, but it wasn't there..
2020-11-06 11:31:09 +03:00
Roman Lebedev a5ae3edaa3
[IR] CmpInst: add getUnsignedPredicate()
There's already getSignedPredicate(), it is not symmetrical to not have
it's opposite. I wanted to use it in new code, but it wasn't there..
2020-11-06 11:31:08 +03:00
David Green 90131e3ecb [CostModel] Make target intrinsics cheap by default
This patch changes the intrinsics cost model to assume that by default
target intrinsics are cheap. This didn't seem to be the case for all
intrinsics, and is potentially an MVE problem due to our scalarization
overheads. Cheap seems to be a good default in general though.

Differential Revision: https://reviews.llvm.org/D90597
2020-11-03 09:58:28 +00:00
Arthur Eubanks 5c31b8b94f Revert "Use uint64_t for branch weights instead of uint32_t"
This reverts commit 10f2a0d662.

More uint64_t overflows.
2020-10-31 00:25:32 -07:00
Arthur Eubanks 10f2a0d662 Use uint64_t for branch weights instead of uint32_t
CallInst::updateProfWeight() creates branch_weights with i64 instead of i32.
To be more consistent everywhere and remove lots of casts from uint64_t
to uint32_t, use i64 for branch_weights.

Reviewed By: davidxl

Differential Revision: https://reviews.llvm.org/D88609
2020-10-30 10:03:46 -07:00
Craig Disselkoen c3783847ae C API: support scalable vectors
This adds support for scalable vector types in the C API and in
llvm-c-test, and also adds a test to ensure that llvm-c-test can properly
roundtrip operations involving scalable vectors.

While creating this diff, I discovered that the C API cannot properly roundtrip
_constant expressions_ involving shufflevector / scalable vectors, but that
seems to be a separate enough issue that I plan to address it in a future diff
(unless reviewers feel it should be addressed here).

Differential Revision: https://reviews.llvm.org/D89816
2020-10-28 18:19:34 -04:00
Adrian Prantl 0b2b50a5d2 [DebugInfo] Expose Fortran array debug info attributes through DIBuilder.
The support of a few debug info attributes specifically for Fortran
arrays have been added to LLVM recently, but there's no way to take
advantage of them through DIBuilder. This patch extends
DIBuilder::createArrayType to enable the settings of those attributes.

Patch by Chih-Ping Chen!

Differential Review: https://reviews.llvm.org/D90323
2020-10-28 13:13:35 -07:00
Alok Kumar Sharma a6dd01afa3 [DebugInfo] Support for DW_TAG_generic_subrange
This is needed to support fortran assumed rank arrays which
have runtime rank.

  Summary:
Fortran assumed rank arrays have dynamic rank. DWARF TAG
DW_TAG_generic_subrange is needed to support that.

  Testing:
unit test cases added (hand-written)
check llvm
check debug-info

Reviewed By: aprantl

Differential Revision: https://reviews.llvm.org/D89218
2020-10-29 01:34:15 +05:30
Mitch Phillips ae76729a01 Revert "[DebugInfo] Expose Fortran array debug info attributes through DIBuilder."
This reverts commit 5b3bf8b453.

This caused a regression in the ASan buildbot. See comments at
https://reviews.llvm.org/D89817 for more information.
2020-10-27 20:50:51 -07:00
Nicolai Hähnle e025d09b21 Revert multiple patches based on "Introduce CfgTraits abstraction"
These logically belong together since it's a base commit plus
followup fixes to less common build configurations.

The patches are:

Revert "CfgInterface: rename interface() to getInterface()"

This reverts commit a74fc48158.

Revert "Wrap CfgTraitsFor in namespace llvm to please GCC 5"

This reverts commit f2a06875b6.

Revert "Try to make GCC5 happy about the CfgTraits thing"

This reverts commit 03a5f7ce12.

Revert "Introduce CfgTraits abstraction"

This reverts commit c0cdd22c72.
2020-10-27 20:33:30 +01:00
Nico Weber 2a4e704c92 Revert "Use uint64_t for branch weights instead of uint32_t"
This reverts commit e5766f25c6.
Makes clang assert when building Chromium, see https://crbug.com/1142813
for a repro.
2020-10-27 09:26:21 -04:00
Arthur Eubanks e5766f25c6 Use uint64_t for branch weights instead of uint32_t
CallInst::updateProfWeight() creates branch_weights with i64 instead of i32.
To be more consistent everywhere and remove lots of casts from uint64_t
to uint32_t, use i64 for branch_weights.

Reviewed By: davidxl

Differential Revision: https://reviews.llvm.org/D88609
2020-10-26 20:24:04 -07:00
Duncan P. N. Exon Smith ebb4ea1d53 IR: Simplify two loops walking ConstantDataSequential, NFC
Follow-up to b2b7cf39d5.

Differential Revision: https://reviews.llvm.org/D90198
2020-10-26 21:55:48 -04:00
Duncan P. N. Exon Smith 52821f6a71 IR: Add a comment at missing std::make_unique calls from b2b7cf39d5, NFC 2020-10-26 21:18:34 -04:00
Adrian Prantl 5b3bf8b453 [DebugInfo] Expose Fortran array debug info attributes through DIBuilder.
The support of a few debug info attributes specifically for Fortran
arrays have been added to LLVM recently, but there's no way to take
advantage of them through DIBuilder. This patch extends
DIBuilder::createArrayType to enable the settings of those attributes.

Patch by Chih-Ping Chen!

Differential Revision: https://reviews.llvm.org/D89817
2020-10-26 16:23:36 -07:00
Duncan P. N. Exon Smith b2b7cf39d5 IR: Clarify ownership of ConstantDataSequentials, NFC
Change `ConstantDataSequential::Next` to a
`unique_ptr<ConstantDataSequential>` and update `CDSConstants` to a
`StringMap<unique_ptr<ConstantDataSequential>>`, making the ownership
more obvious.

Differential Revision: https://reviews.llvm.org/D90083
2020-10-26 18:47:25 -04:00
Duncan P. N. Exon Smith d4c667c9af Avoid unnecessary uses of `MDNode::getTemporary`, NFC
This is a long-delayed follow-up to
5e5b85098d.

`TempMDNode` includes a bunch of machinery for RAUW, and should only be
used when necessary. RAUW wasn't being used in any of these cases... it
was just a placeholder for a self-reference.

Where the real node was using `MDNode::getDistinct`, just replace the
temporary argument with `nullptr`.

Where the real node was using `MDNode::get`, the `replaceOperandWith`
call was "promoting" the node to a distinct one implicitly due to
self-reference detection in `MDNode::handleChangedOperand`. The
`TempMDNode` was serving a purpose by delaying uniquing, but it's way
simpler to just call `MDNode::getDistinct` in the first place.

Note that using a self-reference at all in these places is a hold-over
from before `distinct` metadata existed. It was an old trick to create
distinct nodes. It would be intrusive to change, including bitcode
upgrades, etc., and it's harmless so I'm not sure there's much value in
removing it from existing schemas. After this commit it still has a tiny
memory cost (in the extra metadata operand) but no more overhead in
construction.

Differential Revision: https://reviews.llvm.org/D90079
2020-10-26 17:03:25 -04:00
Nick Desaulniers b7926ce6d7 [IR] add fn attr for no_stack_protector; prevent inlining on mismatch
It's currently ambiguous in IR whether the source language explicitly
did not want a stack a stack protector (in C, via function attribute
no_stack_protector) or doesn't care for any given function.

It's common for code that manipulates the stack via inline assembly or
that has to set up its own stack canary (such as the Linux kernel) would
like to avoid stack protectors in certain functions. In this case, we've
been bitten by numerous bugs where a callee with a stack protector is
inlined into an __attribute__((__no_stack_protector__)) caller, which
generally breaks the caller's assumptions about not having a stack
protector. LTO exacerbates the issue.

While developers can avoid this by putting all no_stack_protector
functions in one translation unit together and compiling those with
-fno-stack-protector, it's generally not very ergonomic or as
ergonomic as a function attribute, and still doesn't work for LTO. See also:
https://lore.kernel.org/linux-pm/20200915172658.1432732-1-rkir@google.com/
https://lore.kernel.org/lkml/20200918201436.2932360-30-samitolvanen@google.com/T/#u

Typically, when inlining a callee into a caller, the caller will be
upgraded in its level of stack protection (see adjustCallerSSPLevel()).
By adding an explicit attribute in the IR when the function attribute is
used in the source language, we can now identify such cases and prevent
inlining.  Block inlining when the callee and caller differ in the case that one
contains `nossp` when the other has `ssp`, `sspstrong`, or `sspreq`.

Fixes pr/47479.

Reviewed By: void

Differential Revision: https://reviews.llvm.org/D87956
2020-10-23 11:55:39 -07:00
Serge Pavlov 7975b8c38d [IR] Merge metadata manipulation code into Value
Now there are two main classes in Value hierarchy, which support metadata,
these are Instruction and GlobalObject. They implement different APIs for
metadata manipulation, which however overlap. This change moves metadata
manipulation code into Value, so descendant classes can use this code for
their operations on metadata.

No functional changes intended.

Differential Revision: https://reviews.llvm.org/D67626
2020-10-23 11:08:26 +07:00
Nikita Popov c0e8c94373 [DomTree] Make assert more precise
Per asbirlea's comment, assert that only instructions, constants
and arguments are passed to this API. Simplify returning true
would not be correct for special Value subclasses like MemoryAccess.
2020-10-22 22:40:06 +02:00
Nikita Popov 32b6e9a450 [DomTree] Accept Value as Def (NFC)
Non-instruction defs like arguments, constants or global values
always dominate all instructions/uses inside the function. This
case currently needs to be treated separately by the caller, see
https://reviews.llvm.org/D89623#inline-832818 for an example.

This patch makes the dominator tree APIs accept a Value instead of
an Instruction and always returns true for the non-Instruction case.

A complication here is that BasicBlocks are also Values. For that
reason we can't support the dominates(Value *, BasicBlock *)
variant, as it would conflict with dominates(BasicBlock *, BasicBlock *),
which has different semantics. For the other two APIs we assert
that the passed value is not a BasicBlock.

Differential Revision: https://reviews.llvm.org/D89632
2020-10-22 18:32:03 +02:00
Artur Pilipenko e8cce5ad89 [RS4GC] NFC. Preparatory refactoring to make GC parseable memcpy
For GC parseable element atomic memcpy/memmove we'll need to
shuffle statepoint arguments. Make it possible by storing the
arguments as Value *, not Use *.
2020-10-21 12:38:20 -07:00
Kazu Hirata 96f372c1e7 [AsmWriter] Construct SlotTracker with the function
This patch teaches BasicBlock::print to construct an instance of
SlotTracker with the containing function.

Without this patch, we dump:

*** IR Dump After LoopInstSimplifyPass ***
; Preheader:
  br label %1

; Loop:
<badref>:                                         ; preds = %1, %0
  br label %1

Note "<badref>" above.  This happens because BasicBlock::print calls:

  SlotTracker SlotTable(this->getModule());

Note that this constructor does not add the contents of functions to
the slot table.  That is, basic blocks are left unnumbered.

This patch fixes the problem by switching to:

  SlotTracker SlotTable(this->getParent());

which does add the contents of the Module and the function,
this->getParent(), to the slot table.

Differential Revision: https://reviews.llvm.org/D89567
2020-10-20 15:01:40 -07:00
Shimin Cui 95bda510fb [ConstantFold] Fold the comparison of bitcasted global values
This is to simplify icmp instructions in the form like:

%cmp = icmp eq i32 (i8*, i8*)* bitcast (i32 (i32**, i32**)* @f32 to i32
%(i8*, i8*)), bitcast (i32 (i64**, i64**) @f64 to i32 (i8*, i8*)*)

Here @f32 and @f64 are two functions.

Differential Revision: https://reviews.llvm.org/D87850
2020-10-20 12:41:49 -07:00
David Stenberg 0c0fcea557 Handle value uses wrapped in metadata for the use-list order
When generating the use-list order, also consider value uses that are
operands which are wrapped in metadata; e.g. llvm.dbg.value operands.

This fixes PR36778. The test case is based on the reproducer from that
report.

Reviewed By: dexonsmith

Differential Revision: https://reviews.llvm.org/D53758
2020-10-20 20:05:59 +02:00
Nicolai Hähnle c0cdd22c72 Introduce CfgTraits abstraction
The CfgTraits abstraction simplfies writing algorithms that are
generic over the type of CFG, and enables writing such algorithms
as regular non-template code that operates on opaque references
to CFG blocks and values.

Implementations of CfgTraits provide operations on the concrete
CFG types, e.g. `IrCfgTraits::BlockRef` is `BasicBlock *`.

CfgInterface is an abstract base class which provides operations
on opaque types CfgBlockRef and CfgValueRef. Those opaque types
encapsulate a `void *`, but the meaning depends on the concrete
CFG type. For example, MachineCfgTraits -- for use with MachineIR
in SSA form -- encodes a Register inside CfgValueRef. Converting
between concrete references and opaque/generic ones is done by
CfgTraits::{fromGeneric,toGeneric}. Convenience methods
CfgTraits::{un}wrap{Iterator,Range} are available as well.

Writing algorithms in terms of CfgInterface adds some overhead
(virtual method calls, plus in same cases it removes the
opportunity to inline iterators), but can be much more convenient
since generic algorithms can be written as non-templates.

This patch adds implementations of CfgTraits for all CFGs on
which dominator trees are calculated, so that the dominator
tree can be ported to this machinery. Only IrCfgTraits (LLVM IR)
and MachineCfgTraits (Machine IR in SSA form) are complete, the
other implementations are limited to the absolute minimum
required to make the upcoming dominator tree changes work.

v5:
- fix MachineCfgTraits::blockdef_iterator and allow it to iterate over
  the instructions in a bundle
- use MachineBasicBlock::printName

v6:
- implement predecessors/successors for all CfgTraits implementations
- fix error in unwrapRange
- rename toGeneric/fromGeneric into wrapRef/unwrapRef to have naming
  that is consistent with {wrap,unwrap}{Iterator,Range}
- use getVRegDef instead of getUniqueVRegDef

v7:
- std::forward fix in wrapping_iterator
- fix typos

v8:
- cleanup operators on CfgOpaqueType
- address other review comments

Change-Id: Ia75f4f268fded33fca11218a7d578c9aec1f3f4d

Differential Revision: https://reviews.llvm.org/D83088
2020-10-20 13:50:52 +02:00
Atmn Patel 595c615606 [IR] Adds mustprogress as a LLVM IR attribute
This adds the LLVM IR attribute `mustprogress` as defined in LangRef through D86233. This attribute will be applied to functions with in languages like C++ where forward progress is guaranteed. Functions without this attribute are not required to make progress.

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D85393
2020-10-20 03:09:57 -04:00
Alok Kumar Sharma 0538353b3b [DebugInfo] Support for DWARF operator DW_OP_over
LLVM rejects DWARF operator DW_OP_over. This DWARF operator is needed
for Flang to support assumed rank array.

  Summary:
Currently LLVM rejects DWARF operator DW_OP_over. Below error is
produced when llvm finds this operator.
[..]
invalid expression
!DIExpression(151, 20, 16, 48, 30, 35, 80, 34, 6)
warning: ignoring invalid debug info in over.ll
[..]
There were some parts missing in support of this operator, which are
now completed.

  Testing
-added a unit testcase
-check-debuginfo
-check-llvm

Reviewed By: aprantl

Differential Revision: https://reviews.llvm.org/D89208
2020-10-17 08:42:28 +05:30
Matt Arsenault 0a7cd99a70 Reapply "OpaquePtr: Add type to sret attribute"
This reverts commit eb9f7c28e5.

Previously this was incorrectly handling linking of the contained
type, so this merges the fixes from D88973.
2020-10-16 11:05:02 -04:00
Jameson Nash 122d92dfc3 fix symbol printing on windows
Similar to MCSymbol::print in 3d6c8ebb58
(llvm-svn: 81682, PR4966), these symbols may need to be quoted to be handled by
the linker correctly.

Reviewed By: compnerd

Differential Revision: https://reviews.llvm.org/D87099
2020-10-15 17:14:55 -04:00
Matt Arsenault 6da31fa4a6 InstCombine: Fix infinite loop in copy-constant-to-alloca transform
This was broken by 16295d521e, when
instructions started being handled and not just constant
expressions. This was re-inserting an equivalent bitcast to the
original memcpy operand, which made a non-functional IR change on
every iteration.

This also fixes a secondary problem where it was inserting
addrspacecasts which may not have been legal (i.e. it changed the
source address space). Start visiting all pointer users and fail out
if we can't process them. Also start handling the relevant memory
intrinsic users. These cases can be dealt with by running
InferAddressSpaces separately.
2020-10-14 12:55:25 -04:00
Ahsan Saghir f3202b30b8 [PowerPC] Add assemble disassemble intrinsics for MMA
This patch adds support for assemble disassemble intrinsics
for MMA.

Reviewed By: bsaleil, #powerpc

Differential Revision: https://reviews.llvm.org/D88739
2020-10-13 13:21:58 -05:00
Simon Pilgrim 9c3138bd6d [InstCombine] visitTrunc - pass through undefs for trunc(shift(trunc/ext(x),c)) patterns
Based on the recent patches D88475 and D88429 where we are losing undef values due to extension/comparisons.

I've added a Constant::mergeUndefsWith method that merges the undef scalar/elements from another Constant into a specific Constant.

Differential Revision: https://reviews.llvm.org/D88687
2020-10-13 14:35:18 +01:00
Simon Pilgrim b752daa26b [InstCombine] Replace getLogBase2 internal helper with ConstantExpr::getExactLogBase2. NFCI.
This exposes the helper for other power-of-2 instcombine folds that I'm intending to add vector support to.

The helper only operated on power-of-2 constants so getExactLogBase2 is a more accurate name.
2020-10-11 10:31:17 +01:00
Alok Kumar Sharma 96bd4d34a2 [DebugInfo] Support for DWARF attribute DW_AT_rank
This patch adds support for DWARF attribute DW_AT_rank.

  Summary:
Fortran assumed rank arrays have dynamic rank. DWARF attribute
DW_AT_rank is needed to support that.

  Testing:
unit test cases added (hand-written)
check llvm
check debug-info

Reviewed By: aprantl

Differential Revision: https://reviews.llvm.org/D89141
2020-10-10 17:51:12 +05:30
Bevin Hansson 14a217534b [IR] Add Type::getFloatingPointTy.
It is possible to get a fltSemantics of a particular Type,
but there is no way to produce a Type based on a
fltSemantics.

This adds the function Type::getFloatingPointTy, which
will return the appropriate floating point Type for a given
fltSemantics.

ConstantFP is modified to use this function instead of
implementing it itself. Also some minor refactors to use
Type::getFltSemantics instead of a hand-rolled version.

Differential Revision: https://reviews.llvm.org/D87512
2020-10-09 10:27:41 +02:00
Philip Reames ef8b4e4fcd Add validity assert on entry to CastInst::isNoopCast [NFC]
This required some minor code reorganization to have a version of castIsValid which worked purely in terms of types.
2020-10-07 14:05:45 -07:00
Amara Emerson 322d0afd87 [llvm][mlir] Promote the experimental reduction intrinsics to be first class intrinsics.
This change renames the intrinsics to not have "experimental" in the name.

The autoupgrader will handle legacy intrinsics.

Relevant ML thread: http://lists.llvm.org/pipermail/llvm-dev/2020-April/140729.html

Differential Revision: https://reviews.llvm.org/D88787
2020-10-07 10:36:44 -07:00
Johannes Doerfert ef48436e62 [AttributeFuncs] Consider `noundef` in `typeIncompatible`
Drop `noundef` for return values that are replaced by void and make it
illegal to put `noundef` on a void value.

Reviewed By: fhahn

Differential Revision: https://reviews.llvm.org/D87306
2020-10-05 23:23:06 -05:00
Johannes Doerfert 2a078c3072 [AttributeFuncs] Consider `align` in `typeIncompatible`
Alignment attributes need to be dropped for non-pointer values.
This also introduces a check into the verifier to ensure you don't use
`align` on anything but a pointer. Test needed to be adjusted
accordingly.

Reviewed By: fhahn

Differential Revision: https://reviews.llvm.org/D87304
2020-10-05 23:23:05 -05:00
Sanjay Patel 149f5b573c [APFloat] convert SNaN to QNaN in convert() and raise Invalid signal
This is an alternate fix (see D87835) for a bug where a NaN constant
gets wrongly transformed into Infinity via truncation.
In this patch, we uniformly convert any SNaN to QNaN while raising
'invalid op'.
But we don't have a way to directly specify a 32-bit SNaN value in LLVM IR,
so those are always encoded/decoded by calling convert from/to 64-bit hex.

See D88664 for a clang fix needed to allow this change.

Differential Revision: https://reviews.llvm.org/D88238
2020-10-01 14:37:38 -04:00
Jamie Schmeiser 71124a9dbd Reland No.3: Add new hidden option -print-changed which only reports changes to IR
A new hidden option -print-changed is added along with code to support
printing the IR as it passes through the opt pipeline in the new pass
manager. Only those passes that change the IR are reported, with others
only having the banner reported, indicating that they did not change the
IR, were filtered out or ignored. Filtering of output via the
-filter-print-funcs is supported and a new supporting hidden option
-filter-passes is added. The latter takes a comma separated list of pass
names and filters the output to only show those passes in the list that
change the IR. The output can also be modified via the -print-module-scope
function.

The code introduces an abstract template base class that generalizes the
comparison of IRs that takes an IR representation as template parameter.
Derived classes provide overrides that provide an event based API
for generalized reporting of IRs as they are changed in the opt pipeline
through the new pass manager.

The first of several instantiations is provided that prints the IR
in a form similar to that produced by -print-after-all with the above
mentioned filtering capabilities. This version, and the others to
follow will be introduced at the upcoming developer's conference.

Reviewed By: aeubanks (Arthur Eubanks), yrouban (Yevgeny Rouban), ychen (Yuanfang Chen), MaskRay (Fangrui Song)

Differential Revision: https://reviews.llvm.org/D86360
2020-10-01 17:39:13 +00:00
Xiang1 Zhang 413577a879 [X86] Support Intel Key Locker
Key Locker provides a mechanism to encrypt and decrypt data with an AES key without having access
to the raw key value by converting AES keys into “handles”. These handles can be used to perform the
same encryption and decryption operations as the original AES keys, but they only work on the current
system and only until they are revoked. If software revokes Key Locker handles (e.g., on a reboot),
then any previous handles can no longer be used.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D88398
2020-09-30 18:08:45 +08:00
Simon Pilgrim 14ff38e235 [InstCombine] visitTrunc - trunc (lshr (sext A), C) --> (ashr A, C) non-uniform support
This came from @lebedev.ri's suggestion to use m_SpecificInt_ICMP for D88429 - since I was going to change the m_APInt to m_Constant for that patch I thought I would do it for the only other user of the APInt first.

I've added a ConstantExpr::getUMin helper - its trivial to add UMAX/SMIN/SMAX but thought I'd wait until we have use cases.

Differential Revision: https://reviews.llvm.org/D88475
2020-09-29 15:01:16 +01:00
Tres Popp eb9f7c28e5 Revert "OpaquePtr: Add type to sret attribute"
This reverts commit 55c4ff91bd.

Issues were introduced as discussed in https://reviews.llvm.org/D88241
where this change made previous bugs in the linker and BitCodeWriter
visible.
2020-09-29 10:31:04 +02:00
Robert Widmann 55f727306e [LLVM-C] Turn a ShuffleVector Constant Into a Getter.
It is not a good idea to expose raw constants in the LLVM C API. Replace this with an explicit getter.

Differential Revision: https://reviews.llvm.org/D88367
2020-09-26 17:32:57 -06:00
Craig Disselkoen 51cad041e0 C API: functions to get mask of a ShuffleVector
This commit fixes a regression (from LLVM 10 to LLVM 11 RC3) in the LLVM
C API.

Previously, commit 1ee6ec2bf removed the mask operand from the
ShuffleVector instruction, storing the mask data separately in the
instruction instead; this reduced the number of operands of
ShuffleVector from 3 to 2. AFAICT, this change unintentionally caused
a regression in the LLVM C API. Specifically, it is no longer possible
to get the mask of a ShuffleVector instruction through the C API. This
patch introduces new functions which together allow a C API user to get
the mask of a ShuffleVector instruction, restoring the functionality
which was previously available through LLVMGetOperand().

This patch also adds tests for this change to the llvm-c-test
executable, which involved adding support for InsertElement,
ExtractElement, and ShuffleVector itself (as well as constant vectors)
to echo.cpp. Previously, vector operations weren't tested at all in
echo.ll.

I also fixed some typos in comments and help-text nearby these changes,
which I happened to spot while developing this patch. Since the typo
fixes are technically unrelated other than being in the same files, I'm
happy to take them out if you'd rather they not be included in the patch.

Differential Revision: https://reviews.llvm.org/D88190
2020-09-25 16:01:05 -07:00
Adrian Prantl 137597d4f4 Add a verifier check that rejects non-distinct DISubprogram function
attachments. They would crash the backend, which expects all
DISubprograms that are not part of the type system to have a unit field.

Clang right before https://reviews.llvm.org/D79967 would generate this
kind of broken IR.

rdar://problem/69534688

Thanks to Fangrui for fixing an assembler test I had missed!

https://reviews.llvm.org/D88270
2020-09-25 12:04:46 -07:00
Matt Arsenault 55c4ff91bd OpaquePtr: Add type to sret attribute
Make the corresponding change that was made for byval in
b7141207a4. Like byval, this requires a
bulk update of the test IR tests to include the type before this can
be mandatory.
2020-09-25 14:07:30 -04:00
Adrian Prantl 8055ae31f4 Revert "Add a verifier check that rejects non-distinct DISubprogram function"
This reverts commit e17f52d623.

while investigating bot breakage.
2020-09-25 10:52:19 -07:00
Adrian Prantl e17f52d623 Add a verifier check that rejects non-distinct DISubprogram function
attachments. They would crash the backend, which expects all
DISubprograms that are not part of the type system to have a unit field.

Clang right before https://reviews.llvm.org/D79967 would generate this
kind of broken IR.

rdar://problem/69534688
2020-09-25 08:15:16 -07:00
Vedant Kumar dfc5a9eb57 [Instruction] Add dropLocation and updateLocationAfterHoist helpers
Introduce a helper which can be used to update the debug location of an
Instruction after the instruction is hoisted. This can be used to safely
drop a source location as recommended by the docs.

For more context, see the discussion in https://reviews.llvm.org/D60913.

Differential Revision: https://reviews.llvm.org/D85670
2020-09-24 15:00:04 -07:00
Matt Arsenault dc08185ca7 IR: Have byref imply dereferenceable
The langref already states it does, but this wasn't implemented. Also
covers inalloca and preallocated. Also helps fix a dependence on
pointer element types.
2020-09-24 09:57:28 -04:00
Matt Arsenault d65a7003c4 OpaquePtr: Add helpers for sret to mirror byval
Sret should really have a type parameter like byval does.
2020-09-24 09:57:28 -04:00
Roman Lebedev 7465da2077
[ConstantRange] Introduce getMinSignedBits() method
Similar to the ConstantRange::getActiveBits(), and to similarly-named
methods in APInt, returns the bitwidth needed to represent
the given signed constant range
2020-09-22 21:37:30 +03:00
Roman Lebedev 2ed9c4c70b
[ConstantRange] Introduce getActiveBits() method
Much like APInt::getActiveBits(), computes how many bits are needed
to be able to represent every value in this constant range,
treating the values as unsigned.
2020-09-22 21:37:29 +03:00
Roman Lebedev b38d897e80
[ConstantRange] binaryXor(): special-case binary complement case - the result is precise
Use the fact that `~X` is equivalent to `-1 - X`, which gives us
fully-precise answer, and we only need to special-handle the wrapped case.

This fires ~16k times for vanilla llvm test-suite + RawSpeed.
2020-09-22 21:37:29 +03:00
Simon Pilgrim 53f1748c13 ProfileSummary.cpp - use auto const& iterator in for-range loop to avoid copies. NFCI. 2020-09-21 16:54:26 +01:00
Matt Arsenault 751a6c5760 IR: Move denormal mode parsing from MachineFunction to Function
This was just inspecting the IR to begin with, and is useful to check
in some places in the IR.
2020-09-18 09:55:47 -04:00
Douglas Yung b03c2b8395 Revert "Re-land: Add new hidden option -print-changed which only reports changes to IR"
The test added in this commit is failing on Windows bots:

http://lab.llvm.org:8011/builders/llvm-clang-win-x-armv7l/builds/1269

This reverts commit f9e6d1edc0 and follow-up commit 6859d95ea2.
2020-09-17 01:32:29 -07:00
Jamie Schmeiser f9e6d1edc0 Re-land: Add new hidden option -print-changed which only reports changes to IR
A new hidden option -print-changed is added along with code to support
printing the IR as it passes through the opt pipeline in the new pass
manager. Only those passes that change the IR are reported, with others
only having the banner reported, indicating that they did not change the
IR, were filtered out or ignored. Filtering of output via the
-filter-print-funcs is supported and a new supporting hidden option
-filter-passes is added. The latter takes a comma separated list of pass
names and filters the output to only show those passes in the list that
change the IR. The output can also be modified via the -print-module-scope
function.

The code introduces a template base class that generalizes the comparison
of IRs that takes an IR representation as template parameter. The
constructor takes a series of lambdas that provide an event based API
for generalized reporting of IRs as they are changed in the opt pipeline
through the new pass manager.

The first of several instantiations is provided that prints the IR
in a form similar to that produced by -print-after-all with the above
mentioned filtering capabilities. This version, and the others to
follow will be introduced at the upcoming developer's conference.

Reviewed By: aeubanks (Arthur Eubanks), yrouban (Yevgeny Rouban), ychen (Yuanfang Chen)

Differential Revision: https://reviews.llvm.org/D86360
2020-09-16 17:25:18 +00:00
Francesco Petrogalli 15e9a6c211 [llvm][CodeGen] Do not scalarize `llvm.masked.[gather|scatter]` operating on scalable vectors.
This patch prevents the `llvm.masked.gather` and `llvm.masked.scatter` intrinsics to be scalarized when invoked on scalable vectors.

The change in `Function.cpp` is needed to prevent the warning that is raised when `getNumElements` is used in place of `getElementCount` on `VectorType` instances. The tests guards for regressions on this change.

The tests makes sure that calls to `llvm.masked.[gather|scatter]` are still scalarized when:

  # the intrinsics are operating on fixed size vectors, and
  # the compiler is not targeting fixed length SVE code generation.

Reviewed By: efriedma, sdesmalen

Differential Revision: https://reviews.llvm.org/D86249
2020-09-16 16:00:28 +00:00
Alok Kumar Sharma 159abe09d2 [DebugInfo][flang] DISubrange support for fortran assumed size array
This is needed to support assumed size array of fortran which can have missing upperBound/count
, contrary to current DISubrange support.
Example:
subroutine sub (array1, array2)
  integer :: array1 (*)
  integer :: array2 (4:9, 10:*)

  array1(7:8) = 9
  array2(5, 10) = 10
end subroutine
Now the validation check is relaxed for fortran.

Reviewed By: aprantl

Differential Revision: https://reviews.llvm.org/D87500
2020-09-16 14:15:53 +05:30
Simon Pilgrim 9eab73fa17 [X86] Update SSE/AVX integer MINMAX intrinsics to emit llvm.smax.* etc. (PR46851)
We're now getting close to having the necessary analysis/combines etc. for the new generic llvm smax/smin/umax/umin intrinsics.

This patch updates the SSE/AVX integer MINMAX intrinsics to emit the generic equivalents instead of the icmp+select code pattern.

Differential Revision: https://reviews.llvm.org/D87603
2020-09-15 11:19:08 +01:00
David Sherwood 69cccb3189 [SVE] Fix isLoadInvariantInLoop for scalable vectors
I've amended the isLoadInvariantInLoop function to bail out for
scalable vectors for now since the invariant.start intrinsic is only
ever generated by the clang frontend for thread locals or struct
and class constructors, neither of which support sizeless types.
In addition, the intrinsic itself does not currently support the
concept of a scaled size, which makes it impossible to compare
the sizes of different scalable objects, e.g. <vscale x 32 x i8>
and <vscale x 16 x i8>.

Added new tests here:

  Transforms/LICM/AArch64/sve-load-hoist.ll
  Transforms/LICM/hoisting.ll

Differential Revision: https://reviews.llvm.org/D87227
2020-09-15 08:30:19 +01:00
Tyker 78de7297ab Reland [AssumeBundles] Use operand bundles to encode alignment assumptions
NOTE: There is a mailing list discussion on this: http://lists.llvm.org/pipermail/llvm-dev/2019-December/137632.html

Complemantary to the assumption outliner prototype in D71692, this patch
shows how we could simplify the code emitted for an alignemnt
assumption. The generated code is smaller, less fragile, and it makes it
easier to recognize the additional use as a "assumption use".

As mentioned in D71692 and on the mailing list, we could adopt this
scheme, and similar schemes for other patterns, without adopting the
assumption outlining.
2020-09-12 15:36:06 +02:00
Eli Friedman d751f86189 [ConstantFold] Make areGlobalsPotentiallyEqual less aggressive.
In particular, we shouldn't make assumptions about globals which are
unnamed_addr: we can fold them together with other globals.

Also while I'm here, use isInterposable() instead of trying to
explicitly name all the different kinds of weak linkage.

Fixes https://bugs.llvm.org/show_bug.cgi?id=47090

Differential Revision: https://reviews.llvm.org/D87123
2020-09-11 17:23:08 -07:00
Eli Friedman 37f2776d1a [ConstantFold] Fold binary arithmetic on scalable vector splats.
It's a nice simplification, and it confuses instcombine if we don't do
it.

Differential Revision: https://reviews.llvm.org/D87422
2020-09-11 16:41:58 -07:00