with 'objc_arc_inert'
Those calls are no-ops, so they can be safely deleted.
rdar://problem/49839633
Differential Revision: https://reviews.llvm.org/D62433
llvm-svn: 363468
it keeps track of becomes too large
ARC optimizer does a top-down and a bottom-up traversal of the whole
function to pair up retain and release instructions and remove them.
This can be expensive if the number of instructions in the function and
pointer states it tracks are large since it has to look at each pointer
state and determine whether the instruction being visited can
potentially use the pointer.
This patch adds a command line option that sets a limit to the number of
pointers it tracks.
rdar://problem/49477063
Differential Revision: https://reviews.llvm.org/D61100
llvm-svn: 359226
DominatorTree::dominate.
ARC contract pass has an optimization that replaces the uses of the
argument of an ObjC runtime function call with the call result.
For example:
; Before optimization
%1 = tail call i8* @foo1()
%2 = tail call i8* @llvm.objc.retainAutoreleasedReturnValue(i8* %1)
store i8* %1, i8** @g0, align 8
; After optimization
%1 = tail call i8* @foo1()
%2 = tail call i8* @llvm.objc.retainAutoreleasedReturnValue(i8* %1)
store i8* %2, i8** @g0, align 8 // %1 is replaced with %2
Before replacing the argument use, DominatorTree::dominate is called to
determine whether the user instruction is dominated by the ObjC runtime
function call instruction. The call to DominatorTree::dominate can be
expensive if the two instructions belong to the same basic block and the
size of the basic block is large. This patch checks the basic block size
and just bails out if the size exceeds the limit set by command line
option "arc-contract-max-bb-size".
rdar://problem/49477063
Differential Revision: https://reviews.llvm.org/D60900
llvm-svn: 359027
metadata into a module flag in the auto-upgrader and make the ARC
contract pass read the marker as a module flag.
This is needed to fix a bug where ARC contract wasn't inserting the
retainRV marker when LTO was enabled, which caused objects returned
from a function to be auto-released.
rdar://problem/49464214
Differential Revision: https://reviews.llvm.org/D60303
llvm-svn: 358047
are annotated with notail.
r356705 annotated calls to objc_retainAutoreleasedReturnValue with
notail on x86-64. This commit teaches ARC optimizer to check the notail
marker on the call before turning it into a tail call.
rdar://problem/38675807
llvm-svn: 356707
This cleans up all CallInst creation in LLVM to explicitly pass a
function type rather than deriving it from the pointer's element-type.
Differential Revision: https://reviews.llvm.org/D57170
llvm-svn: 352909
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
minted `CallBase` class instead of the `CallSite` wrapper.
This moves the largest interwoven collection of APIs that traffic in
`CallSite`s. While a handful of these could have been migrated with
a minorly more shallow migration by converting from a `CallSite` to
a `CallBase`, it hardly seemed worth it. Most of the APIs needed to
migrate together because of the complex interplay of AA APIs and the
fact that converting from a `CallBase` to a `CallSite` isn't free in its
current implementation.
Out of tree users of these APIs can fairly reliably migrate with some
combination of `.getInstruction()` on the `CallSite` instance and
casting the resulting pointer. The most generic form will look like `CS`
-> `cast_or_null<CallBase>(CS.getInstruction())` but in most cases there
is a more elegant migration. Hopefully, this migrates enough APIs for
users to fully move from `CallSite` to the base class. All of the
in-tree users were easily migrated in that fashion.
Thanks for the review from Saleem!
Differential Revision: https://reviews.llvm.org/D55641
llvm-svn: 350503
OptimizeAutoreleaseRVCall skips optimizing llvm.objc.autoreleaseReturnValue if it
sees a user which is llvm.objc.retainAutoreleasedReturnValue, and if they have
equivalent arguments (either identical or equivalent PHIs). It then assumes that
ObjCARCOpt::OptimizeRetainRVCall will optimize the pair instead.
Trouble is, ObjCARCOpt::OptimizeRetainRVCall doesn't know about equivalent PHIs
so optimizes in a different way and we are left with an unoptimized llvm.objc.autoreleaseReturnValue.
This teaches ObjCARCOpt::OptimizeRetainRVCall to also understand PHI equivalence.
rdar://problem/47005143
Reviewed By: ahatanak
Differential Revision: https://reviews.llvm.org/D56235
llvm-svn: 350284
The caller to EraseInstruction had this conditional:
// ARC calls with null are no-ops. Delete them.
if (IsNullOrUndef(Arg))
but the assert inside EraseInstruction only allowed ConstantPointerNull and not
undef or bitcasts.
This adds support for both of these cases.
rdar://problem/47003805
llvm-svn: 350261
We're moving ARC optimisation and ARC emission in clang away from runtime methods
and towards intrinsics. This is the part which actually uses the intrinsics in the ARC
optimizer when both analyzing the existing calls and emitting new ones.
Differential Revision: https://reviews.llvm.org/D55348
Reviewers: ahatanak
llvm-svn: 349534
Summary:
Since the value stored in the cache might be deleted or replaced with
something else, we need to use tracking ValueHandlers instead of plain
Value pointers. It was discovered in one of internal builds, and
unfortunately there is no small reproducer for the issue.
The cache was introduced in rL327328.
Reviewers: ahatanak, pete
Subscribers: hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D48407
llvm-svn: 335201
Review feedback from r328165. Split out just the one function from the
file that's used by Analysis. (As chandlerc pointed out, the original
change only moved the header and not the implementation anyway - which
was fine for the one function that was used (since it's a
template/inlined in the header) but not in general)
llvm-svn: 333954
Summary:
- Add wasm personality function
- Re-categorize the existing `isFuncletEHPersonality()` function into
two different functions: `isFuncletEHPersonality()` and
`isScopedEHPersonality(). This becomes necessary as wasm EH uses scoped
EH instructions (catchswitch, catchpad/ret, and cleanuppad/ret) but not
outlined funclets.
- Changed some callsites of `isFuncletEHPersonality()` to
`isScopedEHPersonality()` if they are related to scoped EH IR-level
stuff.
Reviewers: majnemer, dschuff, rnk
Subscribers: jfb, sbc100, jgravelle-google, eraman, JDevlieghere, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D45559
llvm-svn: 332667
A catchswitch must be the only non-phi instruction in its basic block;
attempting to move a retain or release into a catchswitch basic block
will result in invalid IR. Explicitly mark a CFG hazard in this case to
prevent the code motion.
Differential Revision: https://reviews.llvm.org/D46482
llvm-svn: 332430
The DEBUG() macro is very generic so it might clash with other projects.
The renaming was done as follows:
- git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g'
- git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM
- Manual change to APInt
- Manually chage DOCS as regex doesn't match it.
In the transition period the DEBUG() macro is still present and aliased
to the LLVM_DEBUG() one.
Differential Revision: https://reviews.llvm.org/D43624
llvm-svn: 332240
A catchswitch is both a pad and a terminator, meaning it must be the
only non-phi instruction in its basic block. When we're inserting a
bitcast in the incoming basic block for a phi, if that incoming block is
a catchswitch, we should go up the dominator tree to find a valid
insertion point rather than attempting to insert before the catchswitch
(which would result in invalid IR).
Differential Revision: https://reviews.llvm.org/D46412
llvm-svn: 331548
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
Differential Revision: https://reviews.llvm.org/D46290
llvm-svn: 331272
When creating a call to storeStrong in ObjCARCContract, ensure the call
gets the correct funclet token, otherwise WinEHPrepare will turn the
call (and all subsequent instructions) into unreachable.
We already have logic to do this for the ARC autorelease elision marker;
factor that out into a common function that's used for both. These are
the only two places in this transform that create call instructions.
Differential Revision: https://reviews.llvm.org/D45857
llvm-svn: 330487
Remove #include of Transforms/Scalar.h from Transform/Utils to fix layering.
Transforms depends on Transforms/Utils, not the other way around. So
remove the header and the "createStripGCRelocatesPass" function
declaration (& definition) that is unused and motivated this dependency.
Move Transforms/Utils/Local.h into Analysis because it's used by
Analysis/MemoryBuiltins.cpp.
llvm-svn: 328165
The inline assembly generated for the ARC autorelease elision marker
must have a funclet token if it's emitted inside a funclet, otherwise
the inline assembly (and all subsequent code in the funclet) will be
marked unreachable by WinEHPrepare.
Note that this only applies for the non-O0 case, since at O0, clang
emits the autorelease elision marker itself rather than deferring to the
backend. The fix for clang is handled in a separate change.
Differential Revision: https://reviews.llvm.org/D44641
llvm-svn: 328042
In the case that the CallInst that is being moved has an associated
operand bundle which is a funclet, the move will construct an invalid
instruction. The new site will have a different token and needs to be
reassociated with the new instruction.
Unfortunately, there is no way to alter the bundle after the
construction of the instruction. Replace the call instruction cloning
with a custom helper to clone the instruction and reassociate the
funclet token.
llvm-svn: 327336
Summary:
ProvenanceAnalysis::related(A, B) currently memoizes its results, and on big
tests the cache grows too large, and we're spending most of the time
growing/looking through DenseMap.
This patch reduces the size of the cache by normalizing keys first: we do that
by calling GetUnderlyingObjCPtr on the input values. The results of
GetUnderlyingObjCPtr are also memoized in a separate cache.
The patch doesn't bring noticable changes to compile time on CTMark, however
significantly helps one of our internal tests.
Reviewers: gottesmm
Subscribers: hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D44270
llvm-svn: 327328
to @objc_autorelease if its operand is a PHI and the PHI has an
equivalent value that is used by a return instruction.
For example, ARC optimizer shouldn't replace the call in the following
example, as doing so breaks the AutoreleaseRV/RetainRV optimization:
%v1 = bitcast i32* %v0 to i8*
br label %bb3
bb2:
%v3 = bitcast i32* %v2 to i8*
br label %bb3
bb3:
%p = phi i8* [ %v1, %bb1 ], [ %v3, %bb2 ]
%retval = phi i32* [ %v0, %bb1 ], [ %v2, %bb2 ] ; equivalent to %p
%v4 = tail call i8* @objc_autoreleaseReturnValue(i8* %p)
ret i32* %retval
Also, make sure ObjCARCContract replaces @objc_autoreleaseReturnValue's
operand uses with its value so that the call gets tail-called.
rdar://problem/15894705
llvm-svn: 323009
Summary:
The aim is to make ModRefInfo checks and changes more intuitive
and less error prone using inline methods that abstract the bit operations.
Ideally ModRefInfo would become an enum class, but that change will require
a wider set of changes into FunctionModRefBehavior.
Reviewers: sanjoy, george.burgess.iv, dberlin, hfinkel
Subscribers: nlopes, llvm-commits
Differential Revision: https://reviews.llvm.org/D40749
llvm-svn: 319821
The `BasicBlock::getFirstInsertionPt` call may return `std::end` for the
BB. Dereferencing the end iterator results in an assertion failure
"(!NodePtr->isKnownSentinel()), function operator*". Ensure that the
returned iterator is valid before dereferencing it. If the end is
returned, move one position backward to get a valid insertion point.
llvm-svn: 316401
above PHI instructions.
ARC optimizer has an optimization that moves a call to an ObjC runtime
function above a phi instruction when the phi has a null operand and is
an argument passed to the function call. This optimization should not
kick in when the runtime function is an objc_release that releases an
object with precise lifetime semantics.
rdar://problem/34959669
llvm-svn: 315914
The BasicBlock passed to FindPredecessorRetainWithSafePath should be the
parent block of Autorelease. This fixes a crash that occurs in
FindDependencies when StartInst is not in StartBB.
rdar://problem/33866381
llvm-svn: 312266
I did this a long time ago with a janky python script, but now
clang-format has built-in support for this. I fed clang-format every
line with a #include and let it re-sort things according to the precise
LLVM rules for include ordering baked into clang-format these days.
I've reverted a number of files where the results of sorting includes
isn't healthy. Either places where we have legacy code relying on
particular include ordering (where possible, I'll fix these separately)
or where we have particular formatting around #include lines that
I didn't want to disturb in this patch.
This patch is *entirely* mechanical. If you get merge conflicts or
anything, just ignore the changes in this patch and run clang-format
over your #include lines in the files.
Sorry for any noise here, but it is important to keep these things
stable. I was seeing an increasing number of patches with irrelevant
re-ordering of #include lines because clang-format was used. This patch
at least isolates that churn, makes it easy to skip when resolving
conflicts, and gets us to a clean baseline (again).
llvm-svn: 304787
Summary:
Do three things to help with that:
- Add AttributeList::FirstArgIndex, which is an enumerator currently set
to 1. It allows us to change the indexing scheme with fewer changes.
- Add addParamAttr/removeParamAttr. This just shortens addAttribute call
sites that would otherwise need to spell out FirstArgIndex.
- Remove some attribute-specific getters and setters from Function that
take attribute list indices. Most of these were only used from
BuildLibCalls, and doesNotAlias was only used to test or set if the
return value is malloc-like.
I'm happy to split the patch, but I think they are probably easier to
review when taken together.
This patch should be NFC, but it sets the stage to change the indexing
scheme to this, which is more convenient when indexing into an array:
0: func attrs
1: retattrs
2...: arg attrs
Reviewers: chandlerc, pete, javed.absar
Subscribers: david2050, llvm-commits
Differential Revision: https://reviews.llvm.org/D32811
llvm-svn: 302060
retainAutoreleasedReturnValue that retains the returned value.
This commit fixes a bug in ARC optimizer where it moves a release
between a call and a retainAutoreleasedReturnValue, causing the returned
object to be released before the retainAutoreleasedReturnValue can
retain it.
This commit accomplishes that by doing a lookahead and checking whether
the call prevents the release from moving upwards. In the long term, we
should treat the region between the retainAutoreleasedReturnValue and
the call as a critical section and disallow moving anything there
(possibly using operand bundles).
rdar://problem/20449878
llvm-svn: 301724
We need to do this to prevent a miscompile which sinks an objc_retain
past an objc_release that releases the object objc_retain retains. This
happens because the top-down and bottom-up traversals each determines
the insert point for retain or release individually without knowing
where the other instruction is moved.
For example, when the following IR is fed to the ARC optimizer, the
top-down traversal decides to insert objc_retain right before
objc_release and the bottom-up traversal decides to insert objc_release
right after clang.arc.use.
(IR before ARC optimizer)
%11 = call i8* @objc_retain(i8* %10)
call void (...) @clang.arc.use(%0* %5)
call void @llvm.dbg.value(...)
call void @objc_release(i8* %6)
This reverses the order of objc_release and objc_retain, which causes
the object to be destructed prematurely.
(IR after ARC optimizer)
call void (...) @clang.arc.use(%0* %5)
call void @objc_release(i8* %6)
call void @llvm.dbg.value(...)
%11 = call i8* @objc_retain(i8* %10)
rdar://problem/30530580
llvm-svn: 301289
Fix a bug in ARC contract pass where an iterator that pointed to a
deleted instruction was dereferenced.
It appears that tryToContractReleaseIntoStoreStrong was incorrectly
assuming that a call to objc_retain would not immediately follow a call
to objc_release.
rdar://problem/25276306
llvm-svn: 299507
Summary:
This class is a list of AttributeSetNodes corresponding the function
prototype of a call or function declaration. This class used to be
called ParamAttrListPtr, then AttrListPtr, then AttributeSet. It is
typically accessed by parameter and return value index, so
"AttributeList" seems like a more intuitive name.
Rename AttributeSetImpl to AttributeListImpl to follow suit.
It's useful to rename this class so that we can rename AttributeSetNode
to AttributeSet later. AttributeSet is the set of attributes that apply
to a single function, argument, or return value.
Reviewers: sanjoy, javed.absar, chandlerc, pete
Reviewed By: pete
Subscribers: pete, jholewinski, arsenm, dschuff, mehdi_amini, jfb, nhaehnle, sbc100, void, llvm-commits
Differential Revision: https://reviews.llvm.org/D31102
llvm-svn: 298393
This patch updates a bunch of places where add_dependencies was being explicitly called to add dependencies on intrinsics_gen to instead use the DEPENDS named parameter. This cleanup is needed for a patch I'm working on to add a dependency debugging mode to the build system.
llvm-svn: 287206
instruction.
This avoids dereferencing null in the debug logging if the instruction
was not in fact a return instruction. This potential bug was found by
PVS-Studio.
This actually fixes the last of the "dereferenced a pointer before
checking it for null" reports in the recent PVS-Studio run. However,
there are quite a few reports of this nature that I did not do anything
to fix because they are pretty glaring false positives. They usually
took the form of quite clear correlated checks or a check made in
a separate function. I've even added asserts anywhere this correlation
wasn't pretty obvious and fundamental to the code.
llvm-svn: 285988
Stop looking at users of UndefValue and ConstantPointerNull in the
objective C ARC optimizers. The other users aren't actually
interesting, since they're not pointing at a particular object. I
imagine these calls could be optimized through -instcombine... maybe
they already are?
These early returns will be required at some point in the future, with a
WIP patch that asserts when someone accesses a use-list on ConstantData.
llvm-svn: 282338
ObjC library call with call return.
ARC contraction tries to replace uses of an argument passed to an
objective-c library call with the call return value. For example, in the
following IR, it replaces uses of argument %9 and uses of the values
discovered traversing the chain upwards (%7 and %8) with the call return
%10, if they are dominated by the call to @objc_autoreleaseReturnValue.
This transformation enables code-gen to tail-call the call to
@objc_autoreleaseReturnValue, which is necessary to enable auto release
return value optimization.
%7 = tail call i8* @objc_loadWeakRetained(i8** %6)
%8 = bitcast i8* %7 to %0*
%9 = bitcast %0* %8 to i8*
%10 = tail call i8* @objc_autoreleaseReturnValue(i8* %9)
ret %0* %8
Since r276727, llvm started removing redundant bitcasts and as a result
started feeding the following IR to ARC contraction:
%7 = tail call i8* @objc_loadWeakRetained(i8** %6)
%8 = bitcast i8* %7 to %0*
%9 = tail call i8* @objc_autoreleaseReturnValue(i8* %7)
ret %0* %8
ARC contraction no longer does the optimization described above since it
only traverses the chain upwards and fails to recognize that the
function return can be replaced by the call return. This commit changes
ARC contraction to traverse the chain downwards too and replace uses of
bitcasts with the call return.
rdar://problem/28011339
Differential Revision: https://reviews.llvm.org/D24523
llvm-svn: 281419
Akira Hatanaka