If the size is larger than the index width, truncate it instead
of asserting.
Longer-term we should consider rejecting types larger than the
index size in the verifier, though this is probably tricky in
practice (it's address space dependent, and types are owned by
the context, not the module).
Fixes https://github.com/llvm/llvm-project/issues/116960.
This replaces some of the most frequent offenders of using a DenseMap that
cause a malloc, where the typical element-count is small enough to fit in
an initial stack allocation.
Most of these are fairly obvious, one to highlight is the collectOffset
method of GEP instructions: if there's a GEP, of course it's going to have
at least one offset, but every time we've called collectOffset we end up
calling malloc as well for the DenseMap in the MapVector.
This implements the `nusw` and `nuw` flags for `getelementptr` as
proposed at
https://discourse.llvm.org/t/rfc-add-nusw-and-nuw-flags-for-getelementptr/78672.
The three possible flags are encapsulated in the new `GEPNoWrapFlags`
class. Currently this class has a ctor from bool, interpreted as the
InBounds flag. This ctor should be removed in the future, as code gets
migrated to handle all flags.
There are a few places annotated with `TODO(gep_nowrap)`, where I've had
to touch code but opted to not infer or precisely preserve the new
flags, so as to keep this as NFC as possible and make sure any changes
of that kind get test coverage when they are made.
Rename has/dropPoisonGeneratingFlagsOrMetadata to
has/dropPoisonGeneratingAnnotations and make it also handle
nonnull, align and range return attributes on calls, similar
to the existing handling for !nonnull, !align and !range metadata.
As noted when #82404 was pushed (canonicalizing `sitofp` -> `uitofp`),
different signedness on fp casts can have dramatic performance
implications on different backends.
So, it makes to create a reliable means for the backend to pick its
cast signedness if either are correct.
Further, this allows us to start canonicalizing `sitofp`- > `uitofp`
which may easy middle end analysis.
Closes#86141
As part of the migration to ptradd
(https://discourse.llvm.org/t/rfc-replacing-getelementptr-with-ptradd/68699),
we need to change the representation of the `inrange` attribute, which
is used for vtable splitting.
Currently, inrange is specified as follows:
```
getelementptr inbounds ({ [4 x ptr], [4 x ptr] }, ptr @vt, i64 0, inrange i32 1, i64 2)
```
The `inrange` is placed on a GEP index, and all accesses must be "in
range" of that index. The new representation is as follows:
```
getelementptr inbounds inrange(-16, 16) ({ [4 x ptr], [4 x ptr] }, ptr @vt, i64 0, i32 1, i64 2)
```
This specifies which offsets are "in range" of the GEP result. The new
representation will continue working when canonicalizing to ptradd
representation:
```
getelementptr inbounds inrange(-16, 16) (i8, ptr @vt, i64 48)
```
The inrange offsets are relative to the return value of the GEP. An
alternative design could make them relative to the source pointer
instead. The result-relative format was chosen on the off-chance that we
want to extend support to non-constant GEPs in the future, in which case
this variant is more expressive.
This implementation "upgrades" the old inrange representation in bitcode
by simply dropping it. This is a very niche feature, and I don't think
trying to upgrade it is worthwhile. Let me know if you disagree.
For getelementptr i8 (aka ptradd) we can skip the whole logic and
directly use the offset. As we're now canonicalizing to this form,
it's pretty common and worth having a fast-path for.
Vectors are always bit-packed and don't respect the elements' alignment
requirements. This is different from arrays. This means offsets of
vector GEPs need to be computed differently than offsets of array GEPs.
This PR fixes many places that rely on an incorrect pattern
that always relies on `DL.getTypeAllocSize(GTI.getIndexedType())`.
We replace these by usages of `GTI.getSequentialElementStride(DL)`,
which is a new helper function added in this PR.
This changes behavior for GEPs into vectors with element types for which
the (bit) size and alloc size is different. This includes two cases:
* Types with a bit size that is not a multiple of a byte, e.g. i1.
GEPs into such vectors are questionable to begin with, as some elements
are not even addressable.
* Overaligned types, e.g. i16 with 32-bit alignment.
Existing tests are unaffected, but a miscompilation of a new test is fixed.
---------
Co-authored-by: Nikita Popov <github@npopov.com>
Add an nneg flag to the zext instruction, which specifies that the
argument is non-negative. Otherwise, the result is a poison value.
The primary use-case for the flag is to preserve information when sext
gets replaced with zext due to range-based canonicalization. The nneg
flag allows us to convert the zext back into an sext later. This is
useful for some optimizations (e.g. a signed icmp can fold with sext but
not zext), as well as some targets (e.g. RISCV prefers sext over zext).
Discourse thread: https://discourse.llvm.org/t/rfc-add-zext-nneg-flag/73914
This patch is based on https://reviews.llvm.org/D156444 by
@Panagiotis156, with some implementation simplifications and additional
tests.
---------
Co-authored-by: Panagiotis K <karouzakispan@gmail.com>
In canCreateUndefOrPoison(), take not only poison-generating flags,
but also poison-generating metadata into account. The helpers are
written generically, but I believe the only case that can actually
matter is !range on calls -- !nonnull and !align are only valid on
loads, and those can create undef/poison anyway.
Unfortunately, this negatively impacts logical to bitwise and/or
conversion: For ctpop/ctlz/cttz we always attach !range metadata,
which will now block the transform, because it might introduce
poison. It would be possible to recover this regression by supporting
a ConsiderFlagsAndMetadata=false mode in impliesPoison() and clearing
flags/metadata on visited instructions.
Fixes https://github.com/llvm/llvm-project/issues/59888.
Differential Revision: https://reviews.llvm.org/D142115
This patch mechanically replaces None with std::nullopt where the
compiler would warn if None were deprecated. The intent is to reduce
the amount of manual work required in migrating from Optional to
std::optional.
This is part of an effort to migrate from llvm::Optional to
std::optional:
https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716
Based on the output of include-what-you-use.
This is a big chunk of changes. It is very likely to break downstream code
unless they took a lot of care in avoiding hidden ehader dependencies, something
the LLVM codebase doesn't do that well :-/
I've tried to summarize the biggest change below:
- llvm/include/llvm-c/Core.h: no longer includes llvm-c/ErrorHandling.h
- llvm/IR/DIBuilder.h no longer includes llvm/IR/DebugInfo.h
- llvm/IR/IRBuilder.h no longer includes llvm/IR/IntrinsicInst.h
- llvm/IR/LLVMRemarkStreamer.h no longer includes llvm/Support/ToolOutputFile.h
- llvm/IR/LegacyPassManager.h no longer include llvm/Pass.h
- llvm/IR/Type.h no longer includes llvm/ADT/SmallPtrSet.h
- llvm/IR/PassManager.h no longer includes llvm/Pass.h nor llvm/Support/Debug.h
And the usual count of preprocessed lines:
$ clang++ -E -Iinclude -I../llvm/include ../llvm/lib/IR/*.cpp -std=c++14 -fno-rtti -fno-exceptions | wc -l
before: 6400831
after: 6189948
200k lines less to process is no that bad ;-)
Discourse thread on the topic: https://llvm.discourse.group/t/include-what-you-use-include-cleanup
Differential Revision: https://reviews.llvm.org/D118652
These flags are documented as generating poison values for particular input values. As such, we should really be consistent about their handling with how we handle nsw/nuw/exact/inbounds.
Differential Revision: https://reviews.llvm.org/D115460
In-loop vector reductions which use the llvm.fmuladd intrinsic involve
the creation of two recipes; a VPReductionRecipe for the fadd and a
VPInstruction for the fmul. If the call to llvm.fmuladd has fast-math flags
these should be propagated through to the fmul instruction, so an
interface setFastMathFlags has been added to the VPInstruction class to
enable this.
Differential Revision: https://reviews.llvm.org/D113125
This method parallels the dropPoisonGeneratingFlags on Instruction, but is hoisted to operator to handle constant expressions as well.
This is mostly code movement, but I did go ahead and add the inrange constexpr gep case. This had been discussed previously, but apparently never followed up o.
Fixes an issue where GEP salvaging did not properly account for GEP
instructions which stepped over array elements of width 0 (effectively a
no-op). This unnecessarily produced long expressions by appending
`... + (x * 0)` and potentially extended the number of SSA values used
in the dbg.value. This also erroneously triggered an assert in the
salvage function that the element width would be strictly positive.
These issues are resolved by simply ignoring these useless operands.
Reviewed By: aprantl
Differential Revision: https://reviews.llvm.org/D111809
This is a partial reapply of the original commit and the followup commit
that were previously reverted; this reapply also includes a small fix
for a potential source of non-determinism, but also has a small change
to turn off variadic debug value salvaging, to ensure that any future
revert/reapply steps to disable and renable this feature do not risk
causing conflicts.
Differential Revision: https://reviews.llvm.org/D91722
This reverts commit 386b66b2fc297cda121a3cc8a36887a6ecbcfc68.
> This reapplies c0f3dfb9, which was reverted following the discovery of
> crashes on linux kernel and chromium builds - these issues have since
> been fixed, allowing this patch to re-land.
This reverts commit 36ec97f76ac0d8be76fb16ac521f55126766267d.
The change caused non-determinism in the compiler, see comments on the code
review at https://reviews.llvm.org/D91722.
Reverting to unbreak people's builds until that can be addressed.
This also reverts the follow-up "[DebugInfo] Limit the number of values
that may be referenced by a dbg.value" in
a0bd6105d80698c53ceaa64bbe6e3b7e7bbf99ee.
This reapplies c0f3dfb9, which was reverted following the discovery of
crashes on linux kernel and chromium builds - these issues have since
been fixed, allowing this patch to re-land.
This reverts commit 4397b7095d640f9b9426c4d0135e999c5a1de1c5.
Previous build failures were caused by an error in bitcode reading and
writing for DIArgList metadata, which has been fixed in e5d844b587.
There were also some unnecessary asserts that were being triggered on
certain builds, which have been removed.
This reverts commit dad5caa59e6b2bde8d6cf5b64a972c393c526c82.
The causes of the previous build errors have been fixed in revisions
aa3e78a59fdf3b211be72f1b3221af831665e67d, and
140757bfaaa00110a92d2247a910c847e6e3bcc8
This reverts commit f40976bd01032f4905dde361e709166704581077.
This patch improves salvageDebugInfoImpl by allowing it to salvage arithmetic
operations with two or more non-const operands; this includes the GetElementPtr
instruction, and most Binary Operator instructions. These salvages produce
DIArgList locations and are only valid for dbg.values, as currently variadic
DIExpressions must use DW_OP_stack_value. This functionality is also only added
for salvageDebugInfoForDbgValues; other functions that directly call
salvageDebugInfoImpl (such as in ISel or Coroutine frame building) can be
updated in a later patch.
Differential Revision: https://reviews.llvm.org/D91722
SROA does not correctly account for offsets in TBAA/TBAA struct metadata.
This patch creates functionality for generating new MD with the corresponding
offset and updates SROA to use this functionality.
Differential Revision: https://reviews.llvm.org/D95826
Summary:
this reduces significantly the number of assumes generated without aftecting too much
the information that is preserved. this improves the compile-time cost
of enable-knowledge-retention significantly.
Reviewers: jdoerfert, sstefan1
Reviewed By: jdoerfert
Subscribers: hiraditya, asbirlea, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D79650
Summary:
this reduces significantly the number of assumes generated without aftecting too much
the information that is preserved. this improves the compile-time cost
of enable-knowledge-retention significantly.
Reviewers: jdoerfert, sstefan1
Reviewed By: jdoerfert
Subscribers: hiraditya, asbirlea, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D79650
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
Making a width of GEP Index, which is used for address calculation, to be one of the pointer properties in the Data Layout.
p[address space]:size:memory_size:alignment:pref_alignment:index_size_in_bits.
The index size parameter is optional, if not specified, it is equal to the pointer size.
Till now, the InstCombiner normalized GEPs and extended the Index operand to the pointer width.
It works fine if you can convert pointer to integer for address calculation and all registered targets do this.
But some ISAs have very restricted instruction set for the pointer calculation. During discussions were desided to retrieve information for GEP index from the Data Layout.
http://lists.llvm.org/pipermail/llvm-dev/2018-January/120416.html
I added an interface to the Data Layout and I changed the InstCombiner and some other passes to take the Index width into account.
This change does not affect any in-tree target. I added tests to cover data layouts with explicitly specified index size.
Differential Revision: https://reviews.llvm.org/D42123
llvm-svn: 325102
Instead, expose whether the current type is an array or a struct, if an array
what the upper bound is, and if a struct the struct type itself. This is
in preparation for a later change which will make PointerType derive from
Type rather than SequentialType.
Differential Revision: https://reviews.llvm.org/D26594
llvm-svn: 288458
Summary:
GEPOperator: provide getResultElementType alongside getSourceElementType.
This is made possible by adding a result element type field to GetElementPtrConstantExpr, which GetElementPtrInst already has.
GEP: replace get(Pointer)ElementType uses with get{Source,Result}ElementType.
Reviewers: mjacob, dblaikie
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D16275
llvm-svn: 258145
