We have been using -switch-inst-prof-update-wrapper-strict
set to true by default for some time. It is time to remove
the safety stuff and make SwitchInstProfUpdateWrapper
intolerant to inconsistencies in !prof branch_weights
metadata of SwitchInst.
This patch gets rid of the Invalid state of
SwitchInstProfUpdateWrapper and the option
-switch-inst-prof-update-wrapper-strict. So there is only
two states: changed and unchanged.
Reviewers: davidx, nikic, eraman, reames, chandlerc
Reviewed By: davidx
Differential Revision: https://reviews.llvm.org/D67435
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@371707 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
There's an unspoken invariant of callbr that the list of BlockAddress
Constants in the "function args" list match the BasicBlocks in the
"other labels" list. (This invariant is being added to the LangRef in
https://reviews.llvm.org/D67196).
When modifying the any of the indirect destinations of a callbr
instruction (possible jump targets), we need to update the function
arguments if the argument is a BlockAddress whose BasicBlock refers to
the indirect destination BasicBlock being replaced. Otherwise, many
transforms that modify successors will end up violating that invariant.
A recent change to the arm64 Linux kernel exposed this bug, which
prevents the kernel from booting.
I considered maintaining a mapping from indirect destination BasicBlock
to argument operand BlockAddress, but this ends up being a one to
potentially many (though usually one) mapping. Also, the list of
arguments to a function (or more typically inline assembly) ends up
being less than 10. The implementation is significantly simpler to just
rescan the full list of arguments. Because of the one to potentially
many relationship, the full arg list must be scanned (we can't stop at
the first instance).
Thanks to the following folks that reported the issue and helped debug
it:
* Nathan Chancellor
* Will Deacon
* Andrew Murray
* Craig Topper
Link: https://bugs.llvm.org/show_bug.cgi?id=43222
Link: https://github.com/ClangBuiltLinux/linux/issues/649
Link: https://lists.infradead.org/pipermail/linux-arm-kernel/2019-September/678330.html
Reviewers: craig.topper, chandlerc
Reviewed By: craig.topper
Subscribers: void, javed.absar, kristof.beyls, hiraditya, llvm-commits, nathanchance, srhines
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67252
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@371262 91177308-0d34-0410-b5e6-96231b3b80d8
This patch turns on the prof branch_weights metadata consistency
check in SwitchInstProfUpdateWrapper.
If this patch causes a failure then please before reverting do report
the IR that hits the assertion and try identifying the pass that
introduces the inconsistency. We have to fix all such passes.
See also the upcoming change https://reviews.llvm.org/D61179
in the Verifier.
Reviewers: davidx, nikic, eraman, reames, chandlerc
Reviewed By: davidx
Differential Revision: https://reviews.llvm.org/D64061
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@368129 91177308-0d34-0410-b5e6-96231b3b80d8
This patch removes the test part that relates to the non-strict
behavior of SwitchInstProfUpdateWrapper and changes
the assertion to llvm_unreachable() to allow the check in
release builds.
This patch prepares SwitchInstProfUpdateWrapper to become
strict with one line change. That is need to revert it easily
if any failure will arise.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@365439 91177308-0d34-0410-b5e6-96231b3b80d8
While prof branch_weights inconsistencies are being fixed patch
by patch (pass by pass) we need SwitchInstProfUpdateWrapper to
be safe with respect to inconsistent metadata that can come from
passes that have not been fixed yet. See the bug found by @nikic
in https://reviews.llvm.org/D62126.
This patch introduces one more state (called Invalid) to the
wrapper class that allows users to work with the underlying
SwitchInst ignoring the prof metadata changes.
Created a unit test for the SwitchInstProfUpdateWrapper class.
Reviewers: davidx, nikic, eraman, reames, chandlerc
Reviewed By: davidx
Differential Revision: https://reviews.llvm.org/D62656
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@362473 91177308-0d34-0410-b5e6-96231b3b80d8
This patch introduces a wrapper class that re-implements
several mutator methods of SwitchInst to handle changes
of prof branch_weights metadata along with remove/add
switch case methods.
Subsequent patches will use this wrapper to implement
prof branch_weights metadata handling for SwitchInst.
Reviewers: davidx, eraman, reames, chandlerc
Reviewed By: davidx
Differential Revision: https://reviews.llvm.org/D62122
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@361596 91177308-0d34-0410-b5e6-96231b3b80d8
to CallInst.
The issue was raised here: https://reviews.llvm.org/D60903#1472783
The function Instruction::updateProfWeight is only used for CallInst in
profile update. From the current interface, it is very easy to think that
the function can also be used for branch instruction. However, Branch
instruction does't need the scaling the function provides for
branch_weights and VP (value profile), in addition, scaling may introduce
inaccuracy for branch probablity.
The patch moves the function updateProfWeight from Instruction class to
CallInst to remove the confusion. The patch also changes the scaling of
branch_weights from a loop to a block because we know that ProfileData
for branch_weights of CallInst will only have two operands at most.
Differential Revision: https://reviews.llvm.org/D60911
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@358900 91177308-0d34-0410-b5e6-96231b3b80d8
In PR41304:
https://bugs.llvm.org/show_bug.cgi?id=41304
...we have a case where we want to fold a binop of select-shuffle (blended) values.
Rather than try to match commuted variants of the pattern, we can canonicalize the
shuffles and check for mask equality with commuted operands.
We don't produce arbitrary shuffle masks in instcombine, but select-shuffles are a
special case that the backend is required to handle because we already canonicalize
vector select to this shuffle form.
So there should be no codegen difference from this change. It's possible that this
improves CSE in IR though.
Differential Revision: https://reviews.llvm.org/D60016
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@357366 91177308-0d34-0410-b5e6-96231b3b80d8
This patch accompanies the RFC posted here:
http://lists.llvm.org/pipermail/llvm-dev/2018-October/127239.html
This patch adds a new CallBr IR instruction to support asm-goto
inline assembly like gcc as used by the linux kernel. This
instruction is both a call instruction and a terminator
instruction with multiple successors. Only inline assembly
usage is supported today.
This also adds a new INLINEASM_BR opcode to SelectionDAG and
MachineIR to represent an INLINEASM block that is also
considered a terminator instruction.
There will likely be more bug fixes and optimizations to follow
this, but we felt it had reached a point where we would like to
switch to an incremental development model.
Patch by Craig Topper, Alexander Ivchenko, Mikhail Dvoretckii
Differential Revision: https://reviews.llvm.org/D53765
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@353563 91177308-0d34-0410-b5e6-96231b3b80d8
Recommit r352791 after tweaking DerivedTypes.h slightly, so that gcc
doesn't choke on it, hopefully.
Original Message:
The FunctionCallee type is effectively a {FunctionType*,Value*} pair,
and is a useful convenience to enable code to continue passing the
result of getOrInsertFunction() through to EmitCall, even once pointer
types lose their pointee-type.
Then:
- update the CallInst/InvokeInst instruction creation functions to
take a Callee,
- modify getOrInsertFunction to return FunctionCallee, and
- update all callers appropriately.
One area of particular note is the change to the sanitizer
code. Previously, they had been casting the result of
`getOrInsertFunction` to a `Function*` via
`checkSanitizerInterfaceFunction`, and storing that. That would report
an error if someone had already inserted a function declaraction with
a mismatching signature.
However, in general, LLVM allows for such mismatches, as
`getOrInsertFunction` will automatically insert a bitcast if
needed. As part of this cleanup, cause the sanitizer code to do the
same. (It will call its functions using the expected signature,
however they may have been declared.)
Finally, in a small number of locations, callers of
`getOrInsertFunction` actually were expecting/requiring that a brand
new function was being created. In such cases, I've switched them to
Function::Create instead.
Differential Revision: https://reviews.llvm.org/D57315
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@352827 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit f47d6b38c7a61d50db4566b02719de05492dcef1 (r352791).
Seems to run into compilation failures with GCC (but not clang, where
I tested it). Reverting while I investigate.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@352800 91177308-0d34-0410-b5e6-96231b3b80d8
The FunctionCallee type is effectively a {FunctionType*,Value*} pair,
and is a useful convenience to enable code to continue passing the
result of getOrInsertFunction() through to EmitCall, even once pointer
types lose their pointee-type.
Then:
- update the CallInst/InvokeInst instruction creation functions to
take a Callee,
- modify getOrInsertFunction to return FunctionCallee, and
- update all callers appropriately.
One area of particular note is the change to the sanitizer
code. Previously, they had been casting the result of
`getOrInsertFunction` to a `Function*` via
`checkSanitizerInterfaceFunction`, and storing that. That would report
an error if someone had already inserted a function declaraction with
a mismatching signature.
However, in general, LLVM allows for such mismatches, as
`getOrInsertFunction` will automatically insert a bitcast if
needed. As part of this cleanup, cause the sanitizer code to do the
same. (It will call its functions using the expected signature,
however they may have been declared.)
Finally, in a small number of locations, callers of
`getOrInsertFunction` actually were expecting/requiring that a brand
new function was being created. In such cases, I've switched them to
Function::Create instead.
Differential Revision: https://reviews.llvm.org/D57315
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@352791 91177308-0d34-0410-b5e6-96231b3b80d8
This broke the RISCV build, and even with that fixed, one of the RISCV
tests behaves surprisingly differently with asserts than without,
leaving there no clear test pattern to use. Generally it seems bad for
hte IR to differ substantially due to asserts (as in, an alloca is used
with asserts that isn't needed without!) and nothing I did simply would
fix it so I'm reverting back to green.
This also required reverting the RISCV build fix in r351782.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@351796 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@351636 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This will make migrating code easier and generally seems like a good collection
of API improvements.
Some of these APIs seem like more consistent / better naming of existing
ones. I've retained the old names for migration simplicit and am just
adding the new ones in this commit. I'll try to garbage collect these
once CallSite is gone.
Subscribers: sanjoy, mcrosier, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D55638
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@350109 91177308-0d34-0410-b5e6-96231b3b80d8
a normal base class that provides all common "call" functionality.
This merges two complex CRTP mixins for the common "call" logic and
common operand bundle logic into a single, normal base class of
`CallInst` and `InvokeInst`. Going forward, users can typically
`dyn_cast<CallBase>` and use the resulting API. No more need for the
`CallSite` wrapper. I'm planning to migrate current usage of the wrapper
to directly use the base class and then it can be removed, but those are
simpler and much more incremental steps. The big change is to introduce
this abstraction into the type system.
I've tried to do some basic simplifications of the APIs that I couldn't
really help but touch as part of this:
- I've tried to organize the attribute API and bundle API into groups to
make understanding the API of `CallBase` easier. Without this,
I wasn't able to navigate the API sanely for all of the ways I needed
to modify it.
- I've added what seem like more clear and consistent APIs for getting
at the called operand. These ended up being especially useful to
consolidate the *numerous* duplicated code paths trying to do this.
- I've largely reworked the organization and implementation of the APIs
for computing the argument operands as they needed to change to work
with the new subclass approach.
To minimize any cost associated with this abstraction, I've moved the
operand layout in memory to store the called operand last. This makes
its position relative to the end of the operand array the same,
regardless of the subclass. It should make it much cheaper to reference
from the `CallBase` abstraction, and this is likely one of the most
frequent things to query.
We do still pay one abstraction penalty here: we have to branch to
determine whether there are 0 or 2 extra operands when computing the end
of the argument operand sequence. However, that seems both rare and
should optimize well. I've implemented this in a way specifically
designed to allow it to optimize fairly well. If this shows up in
profiles, we can add overrides of the relevant methods to the subclasses
that bypass this penalty. It seems very unlikely that this will be an
issue as the code was *already* dealing with an ever present abstraction
of whether or not there are operand bundles, so this isn't the first
branch to go into the computation.
I've tried to remove as much of the obvious vestigial API surface of the
old CRTP implementation as I could, but I suspect there is further
cleanup that should now be possible, especially around the operand
bundle APIs. I'm leaving all of that for future work in this patch as
enough things are changing here as-is.
One thing that made this harder for me to reason about and debug was the
pervasive use of unsigned values in subtraction and other arithmetic
computations. I had to debug more than one unintentional wrap. I've
switched a few of these to use `int` which seems substantially simpler,
but I've held back from doing this more broadly to avoid creating
confusing divergence within a single class's API.
I also worked to remove all of the magic numbers used to index into
operands, putting them behind named constants or putting them into
a single method with a comment and strictly using the method elsewhere.
This was necessary to be able to re-layout the operands as discussed
above.
Thanks to Ben for reviewing this (somewhat large and awkward) patch!
Differential Revision: https://reviews.llvm.org/D54788
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@347452 91177308-0d34-0410-b5e6-96231b3b80d8
The IEEE-754 Standard makes it clear that fneg(x) and
fsub(-0.0, x) are two different operations. The former is a bitwise
operation, while the latter is an arithmetic operation. This patch
creates a dedicated FNeg IR Instruction to model that behavior.
Differential Revision: https://reviews.llvm.org/D53877
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346774 91177308-0d34-0410-b5e6-96231b3b80d8
As shown, this is used to eliminate redundant code in InstCombine,
and there are more cases where we should be using this pattern, but
we're currently unintentionally dropping flags.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346282 91177308-0d34-0410-b5e6-96231b3b80d8
We want to remove this fneg API because it would silently fail
if we add an actual fneg instruction to IR (as proposed in
D53877 ).
We have a newer 'match' API that makes checking for
these patterns simpler. It also works with vectors
that may include undef elements in constants.
If any out-of-tree users need updating, they can model
their code changes on this commit:
https://reviews.llvm.org/rL345295
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@345904 91177308-0d34-0410-b5e6-96231b3b80d8
The initial motivation is that we want to remove the
fneg API because that would silently fail if we add
an actual fneg instruction to IR. The same would be
true for the integer ops, so we might as well get rid
of these too.
We have a newer 'match' API that makes checking for
these patterns simpler. It also works with vectors
that may include undef elements in constants.
If any out-of-tree users need updating, they can model
their code changes on these commits:
rL345050
rL345043
rL345042
rL345041
rL345036
rL345030
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@345052 91177308-0d34-0410-b5e6-96231b3b80d8
This was one of the potential follow-ups suggested in D48236,
and these will be used to make matching the patterns in PR38691 cleaner:
https://bugs.llvm.org/show_bug.cgi?id=38691
About the vocabulary: in the DAG, these would be concat_vector with an
undef operand or extract_subvector. Alternate names are discussed in the
review, but I think these are familiar/good enough to proceed. Once we
have uses of them in code, we might adjust if there are better options.
https://reviews.llvm.org/D51392
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@341075 91177308-0d34-0410-b5e6-96231b3b80d8
The core get and set routines move to the `Instruction` class. These
routines are only valid to call on instructions which are terminators.
The iterator and *generic* range based access move to `CFG.h` where all
the other generic successor and predecessor access lives. While moving
the iterator here, simplify it using the iterator utilities LLVM
provides and updates coding style as much as reasonable. The APIs remain
pointer-heavy when they could better use references, and retain the odd
behavior of `operator*` and `operator->` that is common in LLVM
iterators. Adjusting this API, if desired, should be a follow-up step.
Non-generic range iteration is added for the two instructions where
there is an especially easy mechanism and where there was code
attempting to use the range accessor from a specific subclass:
`indirectbr` and `br`. In both cases, the successors are contiguous
operands and can be easily iterated via the operand list.
This is the first major patch in removing the `TerminatorInst` type from
the IR's instruction type hierarchy. This change was discussed in an RFC
here and was pretty clearly positive:
http://lists.llvm.org/pipermail/llvm-dev/2018-May/123407.html
There will be a series of much more mechanical changes following this
one to complete this move.
Differential Revision: https://reviews.llvm.org/D47467
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@340698 91177308-0d34-0410-b5e6-96231b3b80d8
LangRef for BitCast requires that
"The bit sizes of value and the destination type, ty2, must be identical".
Currently verifier allows BitCast of pointer to vector of pointers so that
the sizes are different.
This change fixes that.
Reviewers: arsenm
Reviewed By: arsenm
Subscribers: llvm-commits, wdng
Differential Revision: https://reviews.llvm.org/D50886
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@340249 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This is a follow-up to r334830 and r335031.
In the valueCoversEntireFragment check we now also handle
the situation when there is a variable length array (VLA)
involved, and the length of the array has been reduced to
a constant.
The ConvertDebugDeclareToDebugValue functions that are related
to PHI nodes and load instructions now avoid inserting dbg.value
intrinsics when the value does not, for certain, cover the
variable/fragment that should be described.
In r334830 we assumed that the value always covered the entire
var/fragment and we had assertions in the code to show that
assumption. However, those asserts failed when compiling code
with VLAs, so we removed the asserts in r335031. Now when we
know that the valueCoversEntireFragment check can fail also for
PHI/Load instructions we avoid to insert the faulty dbg.value
intrinsic in such situations. Compared to the Store instruction
scenario we simply drop the dbg.value here (as the variable does
not change its value due to PHI/Load, so an earlier dbg.value
describing the variable should still be valid).
Reviewers: aprantl, vsk, efriedma
Reviewed By: aprantl
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D48547
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@335580 91177308-0d34-0410-b5e6-96231b3b80d8
The optimizer is getting smarter (eg, D47986) about differentiating shuffles
based on its mask values, so we should make queries on the mask constant
operand generally available to avoid code duplication.
We'll probably use this soon in the vectorizers and instcombine (D48023 and
https://bugs.llvm.org/show_bug.cgi?id=37806).
We might clean up TTI a bit more once all of its current 'SK_*' options are
covered.
Differential Revision: https://reviews.llvm.org/D48236
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@335067 91177308-0d34-0410-b5e6-96231b3b80d8
This is a follow-up to r331272.
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.
Patch produced by
for i in $(git grep -l '\@brief'); do perl -pi -e 's/\@brief //g' $i & done
https://reviews.llvm.org/D46290
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@331275 91177308-0d34-0410-b5e6-96231b3b80d8
If we are only truncating bits from the extend we should be able to just use a smaller extend.
If we are truncating more than the extend we should be able to just use a fptrunc since the presense of the fpextend shouldn't affect rounding.
Differential Revision: https://reviews.llvm.org/D43970
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@326595 91177308-0d34-0410-b5e6-96231b3b80d8
NFC intended, syndicate common code to a parametric base class. Part of the original problem is that InvokeInst is a TerminatorInst, unlike CallInst. the problem is solved by introducing a parametrized class paramtertized by its base.
Differential Revision: https://reviews.llvm.org/D40727
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@325778 91177308-0d34-0410-b5e6-96231b3b80d8
Rename getLatchPredicateForGuard to more common name
getFlippedStrictnessPredicate and move it to ICmpInst class.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@324717 91177308-0d34-0410-b5e6-96231b3b80d8
