Commit Graph

225 Commits

Author SHA1 Message Date
Jay Foad 1b758925ad [IR] Merge createReplacementInstr into ConstantExpr::getAsInstruction
createReplacementInstr was a trivial wrapper around
ConstantExpr::getAsInstruction, which also inserted the new instruction
into a basic block. Implement this directly in getAsInstruction by
adding an InsertBefore parameter and change all callers to use it. NFC.

A follow-up patch will remove createReplacementInstr.

Differential Revision: https://reviews.llvm.org/D112791
2021-10-29 15:02:58 +01:00
Kazu Hirata d14d7068b6 [llvm] Use StringRef::contains (NFC) 2021-10-23 08:45:27 -07:00
Erik Desjardins 11c8efd4db [Inline] Introduce Constant::hasOneLiveUse, use it instead of hasOneUse in inline cost model (PR51667)
Otherwise, inlining costs may be pessimized by dead constants.

Fixes https://bugs.llvm.org/show_bug.cgi?id=51667.

Reviewed By: mtrofin, aeubanks

Differential Revision: https://reviews.llvm.org/D109294
2021-10-07 08:33:25 -07:00
Jay Foad 566690b067 [APFloat] Remove BitWidth argument from getAllOnesValue
There's no need to pass this in explicitly because it is
trivially available from the semantics.
2021-10-04 11:32:16 +01:00
Jay Foad a9bceb2b05 [APInt] Stop using soft-deprecated constructors and methods in llvm. NFC.
Stop using APInt constructors and methods that were soft-deprecated in
D109483. This fixes all the uses I found in llvm, except for the APInt
unit tests which should still test the deprecated methods.

Differential Revision: https://reviews.llvm.org/D110807
2021-10-04 08:57:44 +01:00
Nikita Popov af382b9383 [IR] Handle constant expressions in containsUndefinedElement()
If the constant is a constant expression, then getAggregateElement()
will return null. Guard against this before calling HasFn().
2021-09-09 22:04:12 +02:00
Chris Lattner 735f46715d [APInt] Normalize naming on keep constructors / predicate methods.
This renames the primary methods for creating a zero value to `getZero`
instead of `getNullValue` and renames predicates like `isAllOnesValue`
to simply `isAllOnes`.  This achieves two things:

1) This starts standardizing predicates across the LLVM codebase,
   following (in this case) ConstantInt.  The word "Value" doesn't
   convey anything of merit, and is missing in some of the other things.

2) Calling an integer "null" doesn't make any sense.  The original sin
   here is mine and I've regretted it for years.  This moves us to calling
   it "zero" instead, which is correct!

APInt is widely used and I don't think anyone is keen to take massive source
breakage on anything so core, at least not all in one go.  As such, this
doesn't actually delete any entrypoints, it "soft deprecates" them with a
comment.

Included in this patch are changes to a bunch of the codebase, but there are
more.  We should normalize SelectionDAG and other APIs as well, which would
make the API change more mechanical.

Differential Revision: https://reviews.llvm.org/D109483
2021-09-09 09:50:24 -07:00
Kazu Hirata 72bbd1559e [IR] Remove getWithOperandReplaced (NFC)
The function hasn't been used for at least 10 years.
2021-08-27 08:42:57 -07:00
David Sherwood 8439415333 [IR] Let ConstantVector::getSplat use poison instead of undef
This patch updates ConstantVector::getSplat to use poison instead
of undef when using insertelement/shufflevector to splat.

This follows on from D93793.

Differential Revision: https://reviews.llvm.org/D107751
2021-08-10 08:27:43 +01:00
Nikita Popov 7e21ded88d [IR] Don't accept null type in ConstantExpr::getGetElementPtr()
This is the same change as D105653, but for the constant expression
version of the API.
2021-07-17 15:59:31 +02:00
Paul Walker 287d39dd5a [NFC] Fix a few whitespace issues and typos. 2021-07-04 11:49:58 +01:00
Alex Richardson c142c06c19 Place the BlockAddress type in the address space of the containing function
While this should not matter for most architectures (where the program
address space is 0), it is important for CHERI (and therefore Arm Morello).
We use address space 200 for all of our code pointers and without this
change we assert in the SelectionDAG handling of BlockAddress nodes.

It is also useful for AVR: previously programs targeting
AVR that attempt to read their own machine code
via a pointer to a label would instead read from RAM
using a pointer relative to the the start of program flash.

Reviewed By: dylanmckay, theraven
Differential Revision: https://reviews.llvm.org/D48803
2021-07-02 12:17:55 +01:00
Nikita Popov f086ef3e83 [Constants] Handle addrspacecast with opaque pointer type
This is the same change as D104668, but for constant expression
addrspacecasts.
2021-06-23 20:58:08 +02:00
Nikita Popov d9fe96fe26 [OpaquePtr] Support opaque constant expression GEP
Adjust assertions to use isOpaqueOrPointeeTypeMatches() and make
it return an opaque pointer result for an opaque base pointer. We
also need to enumerate the element type, as it is no longer
implicitly enumerated through the pointer type.

Differential Revision: https://reviews.llvm.org/D104655
2021-06-21 20:06:25 +02:00
Fraser Cormack fd3b556958 [Constants] Extend support for scalable-vector splats
This patch extends the various "isXXX" functions of the `Constant` class
to include scalable-vector splats.

In several "isXXX" functions, code that was separately inspecting
`ConstantVector` and `ConstantDataVector` was unified to use
`getSplatValue`, which already includes support for said splats.

In the varous "isNotXXX" functions, code was added to check whether the
scalar splat value -- if any -- satisfies the predicate.

An extra fix for `isNotMinSignedValue` was included, as it previously
crashed when passed a scalable-vector type because it unconditionally
cast to `FixedVectorType`

These changes address numerous missed optimizations, a compiler crash
mentioned above and -- perhaps most egregiously -- an infinite loop in
InstCombine due to the compiler breaking canonical form when it failed
to pick up on a splat in a select instruction.

Test cases have been added to cover as many of these functions as
possible, though existing coverage is slim; it doesn't appear that there
are any in-tree uses of `Constant::isNegativeZeroValue`, for example.

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D103421
2021-06-07 14:37:56 +01:00
Jinsong Ji cd9e1a020c [Constants][PowerPC] Check exactlyValue for ppc_fp128 in isNullValue
PPC_FP128 determines isZero/isNan/isInf using high-order double value
 only. Checking isZero/isNegative might return the isNullValue unexpectedly.
 eg:
   0xM0000000000000000FFFFFFFFFFFFFFFFF

isZero, but it is not NullValue.

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D103634
2021-06-03 20:31:01 +00:00
Nick Desaulniers 8c72749bd9 [LowerConstantIntrinsics] reuse isManifestLogic from ConstantFolding
GlobalVariables are Constants, yet should not unconditionally be
considered true for __builtin_constant_p.

Via the LangRef
https://llvm.org/docs/LangRef.html#llvm-is-constant-intrinsic:

    This intrinsic generates no code. If its argument is known to be a
    manifest compile-time constant value, then the intrinsic will be
    converted to a constant true value. Otherwise, it will be converted
    to a constant false value.

    In particular, note that if the argument is a constant expression
    which refers to a global (the address of which _is_ a constant, but
    not manifest during the compile), then the intrinsic evaluates to
    false.

Move isManifestConstant from ConstantFolding to be a method of
Constant so that we can reuse the same logic in
LowerConstantIntrinsics.

pr/41459

Reviewed By: rsmith, george.burgess.iv

Differential Revision: https://reviews.llvm.org/D102367
2021-05-14 15:35:21 -07:00
Fraser Cormack 3212a08a8c [Constant] Allow ConstantAggregateZero a scalable element count
A ConstantAggregateZero may be created from a scalable vector type.
However, it still assumed fixed number of elements when queried for
them. This patch changes ConstantAggregateZero to correctly report its
element count.

This change fixes a couple of issues. Firstly, it fixes a crash in
Constant::getUniqueValue when called on a scalable-vector
zeroinitializer constant.

Secondly, it fixes a latent bug in GlobalISel's IRTranslator in which
translating a scalable-vector zeroinitializer would hit the assertion in
ConstantAggregateZero::getNumElements when casting to a FixedVectorType,
rather than reporting an error more gracefully. This is currently
hypothetical as the IRTranslator has deeper issues preventing the use of
scalable vector types.

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D102082
2021-05-10 13:51:53 +01:00
Juneyoung Lee 648544f998 [Constant] ConstantStruct/Array should not lower poison to undef
This is a (late) follow-up patch of 8871a4b4ca and
c95f39891a to make ConstantStruct::get/ConstantArray::getImpl
correctly return PoisonValue if all elements are poison.
This was found while discussing about the elements of a vector-typed UndefValue (D99853)
2021-04-08 15:23:12 +09:00
Nikita Popov 9f864d2025 Reapply [ConstantFold] Handle vectors in ConstantFoldLoadThroughBitcast()
There seems to be an impedance mismatch between what the type
system considers an aggregate (structs and arrays) and what
constants consider an aggregate (structs, arrays and vectors).

Adjust the type check to consider vectors as well. The previous
version of the patch dropped the type check entirely, but it
turns out that getAggregateElement() does require the constant
to be an aggregate in some edge cases: For Poison/Undef the
getNumElements() API is called, without checking in advance that
we're dealing with an aggregate. Possibly the implementation should
avoid doing that, but for now I'm adding an assert so the next
person doesn't fall into this trap.
2021-03-21 17:48:21 +01:00
Leonard Chan cf371573b0 [llvm] Change DSOLocalEquivalent type if the underlying global value type changes
We encountered an issue where LTO running on IR that used the DSOLocalEquivalent
constant would result in bad codegen. The underlying issue was ValueMapper wasn't
properly handling DSOLocalEquivalent, so this just adds the machinery for handling
it. This code path is triggered by a fix to DSOLocalEquivalent::handleOperandChangeImpl
where DSOLocalEquivalent could potentially not have the same type as its underlying GV.

This updates DSOLocalEquivalent::handleOperandChangeImpl to change the type if
the GV type changes and handles this constant in ValueMapper.

Differential Revision: https://reviews.llvm.org/D97978
2021-03-09 15:09:48 -08:00
gbtozers e5d958c456 [DebugInfo] Support DIArgList in DbgVariableIntrinsic
This patch updates DbgVariableIntrinsics to support use of a DIArgList for the
location operand, resulting in a significant change to its interface. This patch
does not update all IR passes to support multiple location operands in a
dbg.value; the only change is to update the DbgVariableIntrinsic interface and
its uses. All code outside of the intrinsic classes assumes that an intrinsic
will always have exactly one location operand; they will still support
DIArgLists, but only if they contain exactly one Value.

Among other changes, the setOperand and setArgOperand functions in
DbgVariableIntrinsic have been made private. This is to prevent code from
setting the operands of these intrinsics directly, which could easily result in
incorrect/invalid operands being set. This does not prevent these functions from
being called on a debug intrinsic at all, as they can still be called on any
CallInst pointer; it is assumed that any code directly setting the operands on a
generic call instruction is doing so safely. The intention for making these
functions private is to prevent DIArgLists from being overwritten by code that's
naively trying to replace one of the Values it points to, and also to fail fast
if a DbgVariableIntrinsic is updated to use a DIArgList without a valid
corresponding DIExpression.
2021-03-08 14:36:13 +00:00
Leonard Chan c77659e549 [llvm][IR] Do not place constants with static relocations in a mergeable section
This patch provides two major changes:

1. Add getRelocationInfo to check if a constant will have static, dynamic, or
   no relocations. (Also rename the original needsRelocation to needsDynamicRelocation.)
2. Only allow a constant with no relocations (static or dynamic) to be placed
   in a mergeable section.

This will allow unused symbols that contain static relocations and happen to
fit in mergeable constant sections (.rodata.cstN) to instead be placed in
unique-named sections if -fdata-sections is used and subsequently garbage collected
by --gc-sections.

See https://lists.llvm.org/pipermail/llvm-dev/2021-February/148281.html.

Differential Revision: https://reviews.llvm.org/D95960
2021-02-18 15:39:00 -08:00
Kazu Hirata cfeecdf7b6 [llvm] Use llvm::all_of (NFC) 2021-01-06 18:27:36 -08:00
Juneyoung Lee 8871a4b4ca [Constant] Update ConstantVector::get to return poison if all input elems are poison
The diff was reviewed at D93994
2021-01-07 09:26:07 +09:00
Juneyoung Lee 29f8628d1f [Constant] Add containsPoisonElement
This patch

- Adds containsPoisonElement that checks existence of poison in constant vector elements,
- Renames containsUndefElement to containsUndefOrPoisonElement to clarify its behavior & updates its uses properly

With this patch, isGuaranteedNotToBeUndefOrPoison's tests w.r.t constant vectors are added because its analysis is improved.

Thanks!

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D94053
2021-01-06 12:10:33 +09:00
Simon Pilgrim 313d982df6 [IR] Add ConstantInt::getBool helpers to wrap getTrue/getFalse. 2021-01-05 11:01:10 +00:00
Kazu Hirata 848e8f938f [llvm] Construct SmallVector with iterator ranges (NFC) 2021-01-04 11:42:44 -08:00
Leonard Chan 19bdc8e5a3 [llvm] Fix for failing test from fdbd84c6c8
When handling a DSOLocalEquivalent operand change:

- Remove assertion checking that the `To` type and current type are the
  same type. This is not always a requirement.
- Add a missing bitcast from an old DSOLocalEquivalent to the type of
  the new one.
2020-12-01 15:47:55 -08:00
Leonard Chan 4d7f3d68f1 [llvm] Fix for failing test from cf8ff75bad
Handle null values when handling operand changes for DSOLocalEquivalent.
2020-11-30 17:22:28 -08:00
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
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
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
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
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
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
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
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
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
David Sherwood f4257c5832 [SVE] Make ElementCount members private
This patch changes ElementCount so that the Min and Scalable
members are now private and can only be accessed via the get
functions getKnownMinValue() and isScalable(). In addition I've
added some other member functions for more commonly used operations.
Hopefully this makes the class more useful and will reduce the
need for calling getKnownMinValue().

Differential Revision: https://reviews.llvm.org/D86065
2020-08-28 14:43:53 +01:00
Christopher Tetreault 5a55e2781c [SVE] Remove calls to VectorType::getNumElements from IR
Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D81500
2020-08-27 11:16:10 -07:00
Florian Hahn bc72a3ab94 [Constants] Handle FNeg in getWithOperands.
Currently ConstantExpr::getWithOperands does not handle FNeg and
subsequently treats FNeg as binary operator, leading to an assertion
failure or segmentation fault if built without assertions.

Originally I reproduced this with llvm-dis on a bitcode file, which I
unfortunately cannot share and also cannot really reduce.

But PR45426 describes the same issue and has a reproducer with Clang, so
I'll go with that.

Reviewed By: aprantl

Differential Revision: https://reviews.llvm.org/D86274
2020-08-21 16:50:56 +01:00
Mehdi Amini a407ec9b6d Revert "Revert "[NFC][llvm] Make the contructors of `ElementCount` private.""
Was reverted because MLIR/Flang builds were broken, these APIs have been
fixed in the meantime.
2020-08-19 17:26:36 +00:00
Mehdi Amini 4fc56d70aa Revert "[NFC][llvm] Make the contructors of `ElementCount` private."
This reverts commit 264afb9e6a.
(and dependent 6b742cc48 and fc53bd610f)

MLIR/Flang are broken.
2020-08-19 17:21:37 +00:00
Francesco Petrogalli 264afb9e6a [NFC][llvm] Make the contructors of `ElementCount` private.
Differential Revision: https://reviews.llvm.org/D86120
2020-08-19 16:26:44 +00:00
Christopher Tetreault 021d56abb9 [SVE] Make Constant::getSplatValue work for scalable vector splats
Summary:
Make Constant::getSplatValue recognize scalable vector splats of the
form created by ConstantVector::getSplat. Add unit test to verify that
C == ConstantVector::getSplat(C)->getSplatValue() for fixed width and
scalable vector splats

Reviewers: efriedma, spatel, fpetrogalli, c-rhodes

Reviewed By: efriedma

Subscribers: sdesmalen, tschuett, hiraditya, rkruppe, psnobl, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D82416
2020-07-07 13:45:51 -07:00
Eli Friedman 15440191b5 [IR] Delete llvm::Constants using the correct type.
In most cases, this doesn't have much impact: the destructors just call
the base class destructor anyway.  A few subclasses of ConstantExpr
actually store non-trivial data, though. Make sure we clean up
appropriately.

This is sort of ugly, but I don't see a good alternative given the
constraints.

Issue found by asan buildbots running the testcase for D80330.

Differential Revision: https://reviews.llvm.org/D82509
2020-06-30 12:37:53 -07:00