In the review of D111085 it was pointed out that these functions don't
conform to the naming scheme in use in LLVM. With this commit we should
be good for all of FPEnv.h.
To better reflect the meaning of the now-disambiguated {GlobalValue,
GlobalAlias}::getBaseObject after breaking off GlobalIFunc::getResolverFunction
(D109792), the function is renamed to getAliaseeObject.
Currently the max alignment representable is 1GB, see D108661.
Setting the align of an object to 4GB is desirable in some cases to make sure the lower 32 bits are clear which can be used for some optimizations, e.g. https://crbug.com/1016945.
This uses an extra bit in instructions that carry an alignment. We can store 15 bits of "free" information, and with this change some instructions (e.g. AtomicCmpXchgInst) use 14 bits.
We can increase the max alignment representable above 4GB (up to 2^62) since we're only using 33 of the 64 values, but I've just limited it to 4GB for now.
The one place we have to update the bitcode format is for the alloca instruction. It stores its alignment into 5 bits of a 32 bit bitfield. I've added another field which is 8 bits and should be future proof for a while. For backward compatibility, we check if the old field has a value and use that, otherwise use the new field.
Updating clang's max allowed alignment will come in a future patch.
Reviewed By: hans
Differential Revision: https://reviews.llvm.org/D110451
Currently the max alignment representable is 1GB, see D108661.
Setting the align of an object to 4GB is desirable in some cases to make sure the lower 32 bits are clear which can be used for some optimizations, e.g. https://crbug.com/1016945.
This uses an extra bit in instructions that carry an alignment. We can store 15 bits of "free" information, and with this change some instructions (e.g. AtomicCmpXchgInst) use 14 bits.
We can increase the max alignment representable above 4GB (up to 2^62) since we're only using 33 of the 64 values, but I've just limited it to 4GB for now.
The one place we have to update the bitcode format is for the alloca instruction. It stores its alignment into 5 bits of a 32 bit bitfield. I've added another field which is 8 bits and should be future proof for a while. For backward compatibility, we check if the old field has a value and use that, otherwise use the new field.
Updating clang's max allowed alignment will come in a future patch.
Reviewed By: hans
Differential Revision: https://reviews.llvm.org/D110451
Currently the max alignment representable is 1GB, see D108661.
Setting the align of an object to 4GB is desirable in some cases to make sure the lower 32 bits are clear which can be used for some optimizations, e.g. https://crbug.com/1016945.
This uses an extra bit in instructions that carry an alignment. We can store 15 bits of "free" information, and with this change some instructions (e.g. AtomicCmpXchgInst) use 14 bits.
We can increase the max alignment representable above 4GB (up to 2^62) since we're only using 33 of the 64 values, but I've just limited it to 4GB for now.
The one place we have to update the bitcode format is for the alloca instruction. It stores its alignment into 5 bits of a 32 bit bitfield. I've added another field which is 8 bits and should be future proof for a while. For backward compatibility, we check if the old field has a value and use that, otherwise use the new field.
Updating clang's max allowed alignment will come in a future patch.
Reviewed By: hans
Differential Revision: https://reviews.llvm.org/D110451
As described on D111049, we're trying to remove the <string> dependency from error handling and replace uses of report_fatal_error(const std::string&) with the Twine() variant which can be forward declared.
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
This is basically the same change as 42cc7f3c52
but for integer attributes. Rather than treating each attribute
individually, handle them all the same way. The only thing that
needs to be done per attribute is specify how get/add convert
from/to the raw representation.
This patch adds the functionalities to print MDNode in tree shape. For
example, instead of printing a MDNode like this:
```
<0x5643e1166888> = !DILocalVariable(name: "foo", arg: 2, scope: <0x5643e11c9740>, file: <0x5643e11c6ec0>, line: 8, type: <0x5643e11ca8e0>, flags: DIFlagPublic | DIFlagFwdDecl, align: 8)
```
The printTree/dumpTree functions can give you:
```
<0x5643e1166888> = !DILocalVariable(name: "foo", arg: 2, scope: <0x5643e11c9740>, file: <0x5643e11c6ec0>, line: 8, type: <0x5643e11ca8e0>, flags: DIFlagPublic | DIFlagFwdDecl, align: 8)
<0x5643e11c9740> = distinct !DISubprogram(scope: null, spFlags: 0)
<0x5643e11c6ec0> = distinct !DIFile(filename: "file.c", directory: "/path/to/dir")
<0x5643e11ca8e0> = distinct !DIDerivedType(tag: DW_TAG_pointer_type, baseType: <0x5643e11668d8>, size: 1, align: 2)
<0x5643e11668d8> = !DIBasicType(tag: DW_TAG_unspecified_type, name: "basictype")
```
Which is useful when using it in debugger. Where sometimes printing the
whole module to see all MDNodes is too expensive.
Differential Revision: https://reviews.llvm.org/D110113
AsmWriterContext is a simple compound that stores TypePrinting,
SlotTracker (i.e. "Machine" in AsmWriter), and Module instances -- three
of the most commonly used objects in the AsmWriter infrastructure.
Previously these three objects are passed as separate function arguments
to most of the printer functions in this file. Tidying them up can bring
easier code refactoring on printer functions in the future (e.g. when we
want to pass additional objects to all printer functions).
NOTE: Theoritically, this patch should be NFC.
Differential Revision: https://reviews.llvm.org/D110112
ParameterABIAttributes functions work with unsigned integers as the index, so having the getter be signed makes no sense. Additionally, for this reason, the loop vars that were signed were changed to unsigned too.
Reviewed By: jeroen.dobbelaere
Differential Revision: https://reviews.llvm.org/D110344
We expose the fact that we rely on unsigned wrapping to iterate through
all indexes. This can be confusing. Rather, keeping it as an
implementation detail through an iterator is less confusing and is less
code.
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D110885
`__stdcall`, `__fastcall` and `__vectorcall` return large values via a
hidden pointer argument. However, the size of that argument should not
be included in the argument list byte count suffix added to the
function's decorated name.
This patch fixes that issue so that LLVM generates the same decorated
name as MSVC does.
MSVC example: https://godbolt.org/z/nc35MKPhr
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D110719
To avoid using the AST when emitting diagnostics, split the "dontcall"
attribute into "dontcall-warn" and "dontcall-error", and also add the
frontend attribute value as the LLVM attribute value. This gives us all
the information to report diagnostics we need from within the IR (aside
from access to the original source).
One downside is we directly use LLVM's demangler rather than using the
existing Clang diagnostic pretty printing of symbols.
Previous revisions didn't properly declare the new dependencies.
Reviewed By: nickdesaulniers
Differential Revision: https://reviews.llvm.org/D110364
To avoid using the AST when emitting diagnostics, split the "dontcall"
attribute into "dontcall-warn" and "dontcall-error", and also add the
frontend attribute value as the LLVM attribute value. This gives us all
the information to report diagnostics we need from within the IR (aside
from access to the original source).
One downside is we directly use LLVM's demangler rather than using the
existing Clang diagnostic pretty printing of symbols.
Reviewed By: nickdesaulniers
Differential Revision: https://reviews.llvm.org/D110364
This patch is for fixing potential insertElement-related bugs like D93818.
```
V = UndefValue::get(VecTy);
for(...)
V = Builder.CreateInsertElementy(V, Elt, Idx);
=>
V = PoisonValue::get(VecTy);
for(...)
V = Builder.CreateInsertElementy(V, Elt, Idx);
```
Like above, this patch changes the placeholder V to poison.
The patch will be separated into several commits.
Reviewed By: aqjune
Differential Revision: https://reviews.llvm.org/D110311
This patch emits DW_TAG_namelist and DW_TAG_namelist_item for fortran
namelist variables. DICompositeType is extended to support this fortran
feature.
Reviewed By: aprantl
Differential Revision: https://reviews.llvm.org/D108553
Thinlink provides an opportunity to propagate function attributes across modules, enabling additional propagation opportunities.
This change propagates (currently default off, turn on with `disable-thinlto-funcattrs=1`) noRecurse and noUnwind based off of function summaries of the prevailing functions in bottom-up call-graph order. Testing on clang self-build:
1. There's a 35-40% increase in noUnwind functions due to the additional propagation opportunities.
2. Throughput is measured at 10-15% increase in thinlink time which itself is 1.5% of E2E link time.
Implementation-wise this adds the following summary function attributes:
1. noUnwind: function is noUnwind
2. mayThrow: function contains a non-call instruction that `Instruction::mayThrow` returns true on (e.g. windows SEH instructions)
3. hasUnknownCall: function contains calls that don't make it into the summary call-graph thus should not be propagated from (e.g. indirect for now, could add no-opt functions as well)
Testing:
Clang self-build passes and 2nd stage build passes check-all
ninja check-all with newly added tests passing
Reviewed By: tejohnson
Differential Revision: https://reviews.llvm.org/D36850
This is a fix for the issue reported at
https://reviews.llvm.org/D110043#3019942:
The ElementSize is a uint64_t and as such may be larger than the
index space, or be negative in the index space. This is UB, but
shouldn't cause assertion failures.
We address this by detecting whether the size is too large and
use a zero index in that case (which is always conservatively
correct).
Differential Revision: https://reviews.llvm.org/D110437
In ThinLTO for locals we normally compute the GUID from the name after
prepending the source path to get a unique global id. SamplePGO indirect
call profiles contain the target GUID without this uniquification,
however (unless compiling with -funique-internal-linkage-names).
In order to correctly handle the call edges added to the combined index
for these indirect calls, during importing and bitcode writing we
consult a map of original to full GUID to identify the actual callee.
However, for a large application this was consuming a lot of compile
time as we need to do this repeatedly (especially during importing where
we may traverse call edges multiple times).
To fix this implement a suggestion in one of the FIXME comments, and
actually modify the call edges during a single traversal after the index
is built to perform the fixups once. I combined this fixup with the dead
code analysis performed on the index in order to avoid adding an
additional walk of the index. The dead code analysis is the first
analysis performed on the index.
This reduced the time required for a large thin link with SamplePGO by
about 20%.
No new test added, but I confirmed that there are existing tests that
will fail when no fixup is performed.
Differential Revision: https://reviews.llvm.org/D110374
- This patch adds in the GOFF mangling support to the LLVM data layout string. A corresponding additional line has been added into the data layout section in the language reference documentation.
- Furthermore, this patch also sets the right data layout string for the z/OS target in the SystemZ backend.
Reviewed By: uweigand, Kai, abhina.sreeskantharajan, MaskRay
Differential Revision: https://reviews.llvm.org/D109362
While both GlobalAlias and GlobalIFunc are GlobalIndirectSymbol, their
`getIndirectSymbol()` usage is quite different (GlobalIFunc's resolver
is an entity different from GlobalIFunc itself).
As discussed on https://lists.llvm.org/pipermail/llvm-dev/2020-September/144904.html
("[IR] Modelling of GlobalIFunc"), the name `getBaseObject` is confusing when
used with GlobalIFunc.
To resolve the confusion:
* Move GloalIndirectSymol::getBaseObject to GlobalAlias:: (GlobalIFunc should use `getResolver` instead)
* Change GlobalValue::getBaseObject not to inspect GlobalIFunc. Note: the function has 7 references.
* Add GlobalIFunc::getResolverFunction to peel off potential ConstantExpr indirection
(`strlen` in `test/LTO/Resolution/X86/ifunc.ll`)
Note: GlobalIFunc::getResolver (like GlobalAlias::getAliasee which does not peel
off ConstantExpr indirection) is kept to be used by ValueEnumerator.
Reviewed By: ibookstein
Differential Revision: https://reviews.llvm.org/D109792
And always print it.
This makes some LLVM diagnostics match up better with Clang's diagnostics.
Updated some AMDGPU uses of DiagnosticInfoResourceLimit and now we print
better diagnostics for those.
Reviewed By: dblaikie
Differential Revision: https://reviews.llvm.org/D110204
A logic incompleteness may lead MemorySSA to be too conservative
in its results. Specifically, when dealing with a call of kind
`call i32 bitcast (i1 (i1)* @test to i32 (i32)*)(i32 %1)`, where
the function `test` is declared with readonly attribute, the
bitcast is not looked through, obscuring function attributes. Hence,
some methods of CallBase (e.g., doesNotReadMemory) could provide
suboptimal results.
Differential Revision: https://reviews.llvm.org/D109888
This patch allows sinking an instruction which can have multiple uses in a
single user. We were previously over-restrictive by looking for exactly one use,
rather than one user.
Also added an API for retrieving a unique undroppable user.
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D109700
One of the two inputs of the Shufflevector is often a placeholder.
Previously, there were cases where the placeholder was undef, and there were cases where it was poison.
I added these constructors to create a placeholder consistently.
Changing to use the newly added constructor will be written in a separate patch.
Reviewed By: spatel
Differential Revision: https://reviews.llvm.org/D110146
We implement logic to convert a byte offset into a sequence of GEP
indices for that offset in a number of places. This patch adds a
DataLayout::getGEPIndicesForOffset() method, which implements the
core logic. I've updated SROA, ConstantFolding and InstCombine to
use it, and there's a few more places where it looks relevant.
Differential Revision: https://reviews.llvm.org/D110043
Some buildbots fail with:
> C:\a\llvm-clang-x86_64-expensive-checks-win\llvm-project\llvm\lib\IR\Verifier.cpp(4352): error C2678: binary '==': no operator found which takes a left-hand operand of type 'const llvm::MDOperand' (or there is no acceptable conversion)
Possibly the explicit MDOperand to Metadata* conversion will help?
New field `elements` is added to '!DIImportedEntity', representing
list of aliased entities.
This is needed to dump optimized debugging information where all names
in a module are imported, but a few names are imported with overriding
aliases.
Reviewed By: dblaikie
Differential Revision: https://reviews.llvm.org/D109343
This reverts commit 4ac4e52189.
There are couple of test failures, which needs update of the test cases.
Doing a clean revert and will recommit the change along with fixed
testcases.
The API was removed in 4ac4e52189 in favor of
getUniqueUndroppableUser.
However, this caused a buildbot failure in AbstractCallSiteTest.cpp,
which uses the API and the AbstractCallSite class requires a "use"
rather than a user.
Retain the API so that the unittest compiles and passes.
This patch allows sinking an instruction which can have multiple uses in a
single user. We were previously over-restrictive by looking for exactly one use,
rather than one user.
Also, the API for retrieving undroppable user has been updated accordingly since
in both usecases (Attributor and InstCombine), we seem to care about the user,
rather than the use.
Reviewed-By: nikic
Differential Revision: https://reviews.llvm.org/D109700
This patch adds functionality to check assumption attributes on call
sites as well.
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D109376
Currently, opaque pointers are supported in two forms: The
-force-opaque-pointers mode, where all pointers are opaque and
typed pointers do not exist. And as a simple ptr type that can
coexist with typed pointers.
This patch removes support for the mixed mode. You either get
typed pointers, or you get opaque pointers, but not both. In the
(current) default mode, using ptr is forbidden. In -opaque-pointers
mode, all pointers are opaque.
The motivation here is that the mixed mode introduces additional
issues that don't exist in fully opaque mode. D105155 is an example
of a design problem. Looking at D109259, it would probably need
additional work to support mixed mode (e.g. to generate GEPs for
typed base but opaque result). Mixed mode will also end up
inserting many casts between i8* and ptr, which would require
significant additional work to consistently avoid.
I don't think the mixed mode is particularly valuable, as it
doesn't align with our end goal. The only thing I've found it to
be moderately useful for is adding some opaque pointer tests in
between typed pointer tests, but I think we can live without that.
Differential Revision: https://reviews.llvm.org/D109290
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
integer 0/1 for the operand of bundle "clang.arc.attachedcall"
https://reviews.llvm.org/D102996 changes the operand of bundle
"clang.arc.attachedcall". This patch makes changes to llvm that are
needed to handle the new IR.
This should make it easier to understand what the IR is doing and also
simplify some of the passes as they no longer have to translate the
integer values to the runtime functions.
Differential Revision: https://reviews.llvm.org/D103000
Index is 0 when the return value has the returned attribute. But the
return value cannot have the returned attribute, so the check is
pointless.
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D109334
llvm.vp.select extends the regular select instruction with an explicit
vector length (%evl).
All lanes with indexes at and above %evl are
undefined. Lanes below %evl are taken from the first input where the
mask is true and from the second input otherwise.
Reviewed By: rogfer01
Differential Revision: https://reviews.llvm.org/D105351
Added opt option -print-pipeline-passes to print a -passes compatible
string describing the built pass pipeline.
As an example:
$ opt -enable-new-pm=1 -adce -licm -simplifycfg -o /dev/null /dev/null -print-pipeline-passes
verify,function(adce),function(loop-mssa(licm)),function(simplifycfg<bonus-inst-threshold=1;no-forward-switch-cond;no-switch-to-lookup;keep-loops;no-hoist-common-insts;no-sink-common-insts>),verify,BitcodeWriterPass
At the moment this is best-effort only and there are some known
limitations:
- Not all passes accepting parameters will print their parameters
(currently only implemented for simplifycfg).
- Some ClassName to pass-name mappings are not unique.
- Some ClassName to pass-name mappings are missing (e.g.
BitcodeWriterPass).
Differential Revision: https://reviews.llvm.org/D108298
Added opt option -print-pipeline-passes to print a -passes compatible
string describing the built pass pipeline.
As an example:
$ opt -enable-new-pm=1 -adce -licm -simplifycfg -o /dev/null /dev/null -print-pipeline-passes
verify,function(adce),function(loop-mssa(licm)),function(simplifycfg<bonus-inst-threshold=1;no-forward-switch-cond;no-switch-to-lookup;keep-loops;no-hoist-common-insts;no-sink-common-insts>),verify,BitcodeWriterPass
At the moment this is best-effort only and there are some known
limitations:
- Not all passes accepting parameters will print their parameters
(currently only implemented for simplifycfg).
- Some ClassName to pass-name mappings are not unique.
- Some ClassName to pass-name mappings are missing (e.g.
BitcodeWriterPass).
This is part one of a couple of patches to fully rename these methods.
I've made the mistake of assuming that these indexes are for parameters
multiple times, but actually they're based off of a weird indexing
scheme AttributeList::AttrIndex where 0 is the return value and ~0 is
the function. Hopefully renaming these methods will make this clearer.
Ideally users should use more specific methods like
AttributeList::getFnAttr().
This patch simply adds the name that we want in the end. This is so the
removal of the methods with the original names happens in a separate
change to make it easier for downstream users.
This touches all relevant methods in AttributeList, CallBase, and Function.
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D108788
We have a large compile showing occasional non-deterministic behavior
that is due to DIArgList not being properly uniqued in some cases. I
tracked this down to handleChangedOperands, for which there is a custom
implementation for DIArgList, that does not take care of re-uniquing
after updating the DIArgList Args, unlike the default version of
handleChangedOperands for MDNode.
Since the Args in the DIArgList form the key for the store, this seems
to be occasionally breaking the lookup in that DenseSet. Specifically,
when invoking DIArgList::get() from replaceVariableLocationOp, very
occasionally it returns a new DIArgList object, when one already exists
having the same exact Args pointers. This in turn causes a subsequent
call to Instruction::isIdenticalToWhenDefined on those two otherwise
identical DIArgList objects during a later pass to return false, leading
to different IR in those rare cases.
I modified DIArgList::handleChangedOperands to perform similar
re-uniquing as the MDNode version used by other metadata node types.
This also necessitated a change to the context destructor, since in some
cases we end up with DIArgList as distinct nodes: DIArgList is the only
metadata node type to have a custom dropAllReferences, so we need to
invoke that version on DIArgList in the DistinctMDNodes store to clean
it up properly.
Differential Revision: https://reviews.llvm.org/D108968
In D87099, the mangler learned to quote export directives that contain
special characters. Only alhpanumerical characters as well as
'_', '$', '.' and '@' were exmpt from this quoting. However, at least
binutils considers an unquoted '.' to be syntax and object files
containing such symbols will cause errors during linking. Fix that
by removing '.' from the list of allowed exemptions.
Differential Revision: https://reviews.llvm.org/D100359
It looks like this array was missed in 4276d4a8d0
Fixed tests that expected `elements` to be empty or depeneded on the order of the empty DINode.
Reviewed By: aprantl
Differential Revision: https://reviews.llvm.org/D107024
This patch emits DW_TAG_namelist and DW_TAG_namelist_item for fortran
namelist variables. DICompositeType is extended to support this fortran
feature.
Reviewed By: aprantl
Differential Revision: https://reviews.llvm.org/D108553
Generate btf_tag annotations for function parameters.
A field "annotations" is introduced to DILocalVariable, and
annotations are represented as an DINodeArray, similar to
DIComposite elements. The following example illustrates how
annotations are encoded in IR:
distinct !DILocalVariable(name: "info",, arg: 1, ..., annotations: !10)
!10 = !{!11, !12}
!11 = !{!"btf_tag", !"a"}
!12 = !{!"btf_tag", !"b"}
Differential Revision: https://reviews.llvm.org/D106620
Generate btf_tag annotations for DIGlobalVariable.
A field "annotations" is introduced to DIGlobalVariable, and
annotations are represented as an DINodeArray, similar to
DIComposite elements. The following example illustrates how
annotations are encoded in IR:
distinct !DIGlobalVariable(..., annotations: !10)
!10 = !{!11, !12}
!11 = !{!"btf_tag", !"a"}
!12 = !{!"btf_tag", !"b"}
Differential Revision: https://reviews.llvm.org/D106619
Generate btf_tag annotations for DISubprogram types.
A field "annotations" is introduced to DISubprogram, and
annotations are represented as an DINodeArray, similar to
DIComposite elements. The following example illustrates how
annotations are encoded in IR:
distinct !DISubprogram(..., annotations: !10)
!10 = !{!11, !12}
!11 = !{!"btf_tag", !"a"}
!12 = !{!"btf_tag", !"b"}
Differential Revision: https://reviews.llvm.org/D106618
Add support for the GNU C style __attribute__((error(""))) and
__attribute__((warning(""))). These attributes are meant to be put on
declarations of functions whom should not be called.
They are frequently used to provide compile time diagnostics similar to
_Static_assert, but which may rely on non-ICE conditions (ie. relying on
compiler optimizations). This is also similar to diagnose_if function
attribute, but can diagnose after optimizations have been run.
While users may instead simply call undefined functions in such cases to
get a linkage failure from the linker, these provide a much more
ergonomic and actionable diagnostic to users and do so at compile time
rather than at link time. Users instead may be able use inline asm .err
directives.
These are used throughout the Linux kernel in its implementation of
BUILD_BUG and BUILD_BUG_ON macros. These macros generally cannot be
converted to use _Static_assert because many of the parameters are not
ICEs. The Linux kernel still needs to be modified to make use of these
when building with Clang; I have a patch that does so I will send once
this feature is landed.
To do so, we create a new IR level Function attribute, "dontcall" (both
error and warning boil down to one IR Fn Attr). Then, similar to calls
to inline asm, we attach a !srcloc Metadata node to call sites of such
attributed callees.
The backend diagnoses these during instruction selection, while we still
know that a call is a call (vs say a JMP that's a tail call) in an arch
agnostic manner.
The frontend then reconstructs the SourceLocation from that Metadata,
and determines whether to emit an error or warning based on the callee's
attribute.
Link: https://bugs.llvm.org/show_bug.cgi?id=16428
Link: https://github.com/ClangBuiltLinux/linux/issues/1173
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D106030
Generate btf_tag annotations for DIDrived types. More specifically,
clang frontend generates the btf_tag annotations for record
fields. The annotations are represented as an DINodeArray
in DebugInfo. The following example illustrate how
annotations are encoded in IR:
distinct !DIDerivedType(tag: DW_TAG_member, ..., annotations: !10)
!10 = !{!11, !12}
!11 = !{!"btf_tag", !"a"}
!12 = !{!"btf_tag", !"b"}
Differential Revision: https://reviews.llvm.org/D106616
Clang patch D106614 added attribute btf_tag support. This patch
generates btf_tag annotations for DIComposite types.
A field "annotations" is introduced to DIComposite, and the
annotations are represented as an DINodeArray, similar to
DIComposite elements. The following example illustrates
how annotations are encoded in IR:
distinct !DICompositeType(..., annotations: !10)
!10 = !{!11, !12}
!11 = !{!"btf_tag", !"a"}
!12 = !{!"btf_tag", !"b"}
Each btf_tag annotation is represented as a 2D array of
meta strings. Each record may have more than one
btf_tag annotations, as in the above example.
Reland with additional fixes for llvm/unittests/IR/DebugTypeODRUniquingTest.cpp.
Differential Revision: https://reviews.llvm.org/D106615
The COFF specific `DataReferencedByCode` complexity (D103372 D103717) is due to
a link.exe limitation: an external symbol in IMAGE_COMDAT_SELECT_ASSOCIATIVE is
not really dropped, so it can cause duplicate definition error.
Clang patch D106614 added attribute btf_tag support. This patch
generates btf_tag annotations for DIComposite types.
A field "annotations" is introduced to DIComposite, and the
annotations are represented as an DINodeArray, similar to
DIComposite elements. The following example illustrates
how annotations are encoded in IR:
distinct !DICompositeType(..., annotations: !10)
!10 = !{!11, !12}
!11 = !{!"btf_tag", !"a"}
!12 = !{!"btf_tag", !"b"}
Each btf_tag annotation is represented as a 2D array of
meta strings. Each record may have more than one
btf_tag annotations, as in the above example.
Differential Revision: https://reviews.llvm.org/D106615
This patch adds vector-predicated ("VP") reduction intrinsics corresponding to
each of the existing unpredicated `llvm.vector.reduce.*` versions. Unlike the
unpredicated reductions, all VP reductions have a start value. This start value
is returned when the no vector element is active.
Support for expansion on targets without native vector-predication support is
included.
This patch is based on the ["reduction
slice"](https://reviews.llvm.org/D57504#1732277) of the LLVM-VP reference patch
(https://reviews.llvm.org/D57504).
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D104308
SwitchInst should have a void result type.
Add a check to the verifier to catch this error.
Reviewed By: samparker
Differential Revision: https://reviews.llvm.org/D108084
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
When LLVM is used in other projects, it may happen that global cons-
tructors will execute before the call to ParseCommandLineOptions.
Since OptBisect is initialized via a constructor, and has no ability
to be updated at a later time, passing "-opt-bisect-limit" to the
parse function may have no effect.
To avoid this problem use a cl::cb (callback) to set the bisection
limit when the option is actually processed.
Differential Revision: https://reviews.llvm.org/D104551
It's entirely possible (because it actually happened) for a bool
variable to end up with a 256-bit DW_AT_const_value. This came about
when a local bool variable was initialized from a bitfield in a
32-byte struct of bitfields, and after inlining and constant
propagation, the variable did have a constant value. The sequence of
optimizations had it carrying "i256" values around, but once the
constant made it into the llvm.dbg.value, no further IR changes could
affect it.
Technically the llvm.dbg.value did have a DIExpression to reduce it
back down to 8 bits, but the compiler is in no way ready to emit an
oversized constant *and* a DWARF expression to manipulate it.
Depending on the circumstances, we had either just the very fat bool
value, or an expression with no starting value.
The sequence of optimizations that led to this state did seem pretty
reasonable, so the solution I came up with was to invent a DWARF
constant expression folder. Currently it only does convert ops, but
there's no reason it couldn't do other ops if that became useful.
This broke three tests that depended on having convert ops survive
into the DWARF, so I added an operator that would abort the folder to
each of those tests.
Differential Revision: https://reviews.llvm.org/D106915
Constant::getSplatValue has O(N) time complexity in the worst case,
where N is the # of elements in a vector. So we call
Constant::getAggregateElement first and return earlier if possible to
avoid unnecessary getSplatValue calls.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D107252
This patch adds an initial ShuffleVectorInst::isInsertSubvectorMask helper to recognize 2-op shuffles where the lowest elements of one of the sources are being inserted into the "in-place" other operand, this includes "concat_vectors" patterns as can be seen in the Arm shuffle cost changes. This also helped fix a x86 issue with irregular/length-changing SK_InsertSubvector costs - I'm hoping this will help with D107188
This doesn't currently attempt to work with 1-op shuffles that could either be a "widening" shuffle or a self-insertion.
The self-insertion case is tricky, but we currently always match this with the existing SK_PermuteSingleSrc logic.
The widening case will be addressed in a follow up patch that treats the cost as 0.
Masks with a high number of undef elts will still struggle to match optimal subvector widths - its currently bounded by minimum-width possible insertion, whilst some cases would benefit from wider (pow2?) subvectors.
Differential Revision: https://reviews.llvm.org/D107228
We might want to use info from GC strategy in middle end analysis.
The motivation for this is provided in D99135: we may want to ask
a GC if it's going to work with a given pointer (currently this code
makes naive check by the method name).
Differetial Revision: https://reviews.llvm.org/D100559
Reviewed By: reames
Currently, the default alignment is much larger than the actual size of
the vector in memory. Fix this to use a sane default.
For SVE, temporarily remove lowering of load/store operations for
predicates with less than 16 elements. The layout the backend was
assuming for SVE predicates with less than 16 elements doesn't agree
with the frontend. More work probably needs to be done here.
This change is, strictly speaking, not backwards-compatible at the
bitcode level. But probably nobody is actually depending on that; i1
vectors in memory are rare, and the code that does use them probably
ends up forcing the alignment to something sane anyway. If we think
this is a concern, I can restrict this to scalable vectors for now
(where it's actually causing issues for me at the moment).
Differential Revision: https://reviews.llvm.org/D88994
Target-dependent constant folding will fold these down to simple
constants (or at least, expressions that don't involve a GEP). We don't
need heroics to try to optimize the form of the expression before that
happens.
Fixes https://bugs.llvm.org/show_bug.cgi?id=51232 .
Differential Revision: https://reviews.llvm.org/D107116
This is a second attempt to fix the EXPENSIVE_CHECKS issue that was mentioned In D91661#2875179 by @jroelofs.
(The first attempt was in D105983)
D91661 more or less completely reverted D49126 and by doing so also removed the cleanup logic of the created declarations and calls.
This patch is a replacement for D91661 (which must itself be reverted first). It replaces the custom declaration creation with the
generic version and shows the test impact. It also tracks the number of NamedValues to detect if a new prototype was added instead
of looking at the available users of a prototype.
Reviewed By: jroelofs
Differential Revision: https://reviews.llvm.org/D106147
When hoisting/moving calls to locations, we strip unknown metadata. Such calls are usually marked `speculatable`, i.e. they are guaranteed to not cause undefined behaviour when run anywhere. So, we should strip attributes that can cause immediate undefined behaviour if those attributes are not valid in the context where the call is moved to.
This patch introduces such an API and uses it in relevant passes. See
updated tests.
Fix for PR50744.
Reviewed By: nikic, jdoerfert, lebedev.ri
Differential Revision: https://reviews.llvm.org/D104641
This fixes an assert firing when compiling code which involves 128 bit
integrals.
This would trigger runtime checks similar to this:
```
Assertion failed: getMinSignedBits() <= 64 && "Too many bits for int64_t", file llvm/include/llvm/ADT/APInt.h, line 1646
```
To get around this, we just saturate those big values.
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D105320
DIEnumerator stores an APInt as of April 2020, so now we don't need to
truncate the enumerator value to 64 bits. Fixes assertions during IRGen.
Split from D105320, thanks to Matheus Izvekov for the test case and
report.
Differential Revision: https://reviews.llvm.org/D106585
Proposed alternative to D105338.
This is ugly, but short-term I think it's the best way forward: first,
let's formalize the hacks into a coherent model. Then we can consider
extensions of that model (we could have different flavors of volatile
with different rules).
Differential Revision: https://reviews.llvm.org/D106309
This adjusts mayHaveSideEffect() to return true for !willReturn()
instructions. Just like other side-effects, non-willreturn calls
(aka "divergence") cannot be removed and cannot be reordered relative
to other side effects. This fixes a number of bugs where
non-willreturn calls are either incorrectly dropped or moved. In
particular, it also fixes the last open problem in
https://bugs.llvm.org/show_bug.cgi?id=50511.
I performed a cursory review of all current mayHaveSideEffect()
uses, which convinced me that these are indeed the desired default
semantics. Places that do not want to consider non-willreturn as a
sideeffect generally do not want mayHaveSideEffect() semantics at
all. I identified two such cases, which are addressed by D106591
and D106742. Finally, there is a use in SCEV for which we don't
really have an appropriate API right now -- what it wants is
basically "would this be considered forward progress". I've just
spelled out the previous semantics there.
Differential Revision: https://reviews.llvm.org/D106749
Rather than adding methods for dropping these attributes in
various places, add a function that returns an AttrBuilder with
these attributes, which can then be used with existing methods
for dropping attributes. This is with an eye on D104641, which
also needs to drop them from returns, not just parameters.
Also be more explicit about the semantics of the method in the
documentation. Refer to UB rather than Undef, which is what this
is actually about.
From LangRef:
> if the parameter or return pointer is null, poison value is
> returned or passed instead. The nonnull attribute should be
> combined with the noundef attribute to ensure a pointer is not
> null or otherwise the behavior is undefined.
Dropping noundef is sufficient to prevent UB. Including nonnull
in this method just muddies the semantics.
This was previously combining indices even though they operate on
different types. For non-opaque pointers, the condition is
automatically satisfied based on the pointer types being equal.
This is part of a patch series working towards the ability to make
SourceLocation into a 64-bit type to handle larger translation units.
!srcloc is generated in clang codegen, and pulled back out by llvm
functions like AsmPrinter::emitInlineAsm that need to report errors in
the inline asm. From there it goes to LLVMContext::emitError, is
stored in DiagnosticInfoInlineAsm, and ends up back in clang, at
BackendConsumer::InlineAsmDiagHandler(), which reconstitutes a true
clang::SourceLocation from the integer cookie.
Throughout this code path, it's now 64-bit rather than 32, which means
that if SourceLocation is expanded to a 64-bit type, this error report
won't lose half of the data.
The compiler will tolerate both of i32 and i64 !srcloc metadata in
input IR without faulting. Test added in llvm/MC. (The semantic
accuracy of the metadata is another matter, but I don't know of any
situation where that matters: if you're reading an IR file written by
a previous run of clang, you don't have the SourceManager that can
relate those source locations back to the original source files.)
Original version of the patch by Mikhail Maltsev.
Reviewed By: dexonsmith
Differential Revision: https://reviews.llvm.org/D105491
Remove the assert in AssemblyWriter::printBasicBlock() and
in BasicBlock::isEntryBlock() that require blocks to have parents.
Instead, have BasicBlock::isEntryBlock() return false for unattached
blocks. This allows us to call these functions for blocks that are
not yet added to a module which is a useful debugging capability.
Committing for xiaoqing_wu
https://reviews.llvm.org/D106127k
In the textual format, `noduplicates` means no COMDAT/section group
deduplication is performed. Therefore, if both sets of sections are retained, and
they happen to define strong external symbols with the same names,
there will be a duplicate definition linker error.
In PE/COFF, the selection kind lowers to `IMAGE_COMDAT_SELECT_NODUPLICATES`.
The name describes the corollary instead of the immediate semantics. The name
can cause confusion to other binary formats (ELF, wasm) which have implemented/
want to implement the "no deduplication" selection kind. Rename it to be clearer.
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D106319
For musttail calls, ABI attributes between the function and the
musttail call must match. The current check discards the type of
type attributes like byval, which means that it will consider
byval(i32) and byval(i64) (or similar) as compatible.
I assume this is a leftover from before these attributes had a
type argument. Ran into this while trying to tighten an assertion
in AttrBuilder.
Differential Revision: https://reviews.llvm.org/D105841
Use the elementtype attribute introduced in D105407 for the
llvm.preserve.array/struct.index intrinsics. It carries the
element type of the GEP these intrinsics effectively encode.
This patch:
* Adds a verifier check that the attribute is required.
* Adds it in the IRBuilder methods for these intrinsics.
* Autoupgrades old bitcode without the attribute.
* Updates the lowering code to use the attribute rather than
the pointer element type.
* Updates lots of tests to specify the attribute.
* Adds -force-opaque-pointers to the intrinsic-array.ll test
to demonstrate they work now.
https://reviews.llvm.org/D106184
As suggested on D105733, this adds a verifier rule that calls to
intrinsics must match the signature of the intrinsic.
Without opaque pointers this is automatically enforced for all
calls, because the pointer types need to match. If the signatures
don't match, a pointer bitcast has to be inserted. For intrinsics
in particular, such bitcasts are not legal, because the address of
intrinsics cannot be taken.
With opaque pointers, there are no more pointer bitcasts, so it's
generally possible for the call and the callee signature to differ.
However, for intrinsics we still want to enforce that the signatures
must match, the same as was done before through the address taken
check.
We can't enforce this more generally for non-intrinsics, because
calls with mismatched signatures at the very least can legally
occur in unreachable code, and might also be valid in some other
cases, depending on how exactly the signatures differ.
Differential Revision: https://reviews.llvm.org/D106013
Intrinsics can only be called directly, taking their address is not
legal. This is currently only enforced for intrinsics that have an
ID, rather than all intrinsics. Adjust the check to cover all
intrinsics.
This came up in D106013.
Differential Revision: https://reviews.llvm.org/D106095
This implements the elementtype attribute specified in D105407. It
just adds the attribute and the specified verifier rules, but
doesn't yet make use of it anywhere.
Differential Revision: https://reviews.llvm.org/D106008
With the current deref semantics, this is redundant - since we assume that anything which is dereferenceable (ever) can't be freed - but it becomes neccessary for the deref-at-point semantics.
Testing wise, this is covered by test/CodeGen/X86/hoist-invariant-load.ll when -use-dereferenceable-at-point-semantics is active. I didn't bother duplicating the command line since a) it's an in-development mode, and b) the change is pretty obvious.
While it is nice to have separate methods in the public AttributeSet
API, we can fetch the type from the internal AttributeSetNode
using a generic API for all type attribute kinds.
A couple of attributes had explicit checks for incompatibility
with pointer types. However, this is already handled generically
by the typeIncompatible() check. We can drop these after adding
SwiftError to typeIncompatible().
However, the previous implementation of the check prints out all
attributes that are incompatible with a given type, even though
those attributes aren't actually used. This has the annoying
result that the error message changes every time a new attribute
is added to the list. Improve this by explicitly finding which
attribute isn't compatible and printing just that.
Add tests for D105088, as well as an option to disable the
(generally) unsound inttoptr of ptrtoint optimization.
Differential Revision: https://reviews.llvm.org/D105771
It is possible that the remangled name for an intrinsic already exists with a different (and wrong) prototype within the module.
As the bitcode reader keeps both versions of all remangled intrinsics around for a longer time, this can result in a
crash, as can be seen in https://bugs.llvm.org/show_bug.cgi?id=50923
This patch makes 'remangleIntrinsicFunction' aware of this situation. When it is detected, it moves the version with the wrong prototype to a different name. That version will be removed anyway once the module is completely loaded.
With thanks to @asbirlea for reporting this issue when trying out an lto build with the full restrict patches, and @efriedma for suggesting a sane resolution mechanism.
Reviewed By: apilipenko
Differential Revision: https://reviews.llvm.org/D105118
Continuing from D105763, this allows placing certain properties
about attributes in the TableGen definition. In particular, we
store whether an attribute applies to fn/param/ret (or a combination
thereof). This information is used by the Verifier, as well as the
ForceFunctionAttrs pass. I also plan to use this in LLParser,
which also duplicates info on which attributes are valid where.
This keeps metadata about attributes in one place, and makes it
more likely that it stays in sync, rather than in various
functions spread across the codebase.
Differential Revision: https://reviews.llvm.org/D105780
This is now the same as isIntAttrKind(), so use that instead, as
it does not require manual maintenance. The naming is also more
accurate in that both int and type attributes have an argument,
but this method was only targeting int attributes.
I initially wanted to tighten the AttrBuilder assertion, but we
have some in-tree uses that would violate it.
Assert that enum/int/type attributes go through the constructor
they are supposed to use.
To make sure this can't happen via invalid bitcode, explicitly
verify that the attribute kind if correct there.
Followup to D105658 to make AttrBuilder automatically work with
new type attributes. TableGen is tweaked to emit First/LastTypeAttr
markers, based on which we can handle type attributes
programmatically.
Differential Revision: https://reviews.llvm.org/D105763
In the spirit of TRegions [0], this patch analyzes a kernel and tracks
if it can be executed in SPMD-mode. If so, we flip the arguments of
the __kmpc_target_init and deinit call to enable the mode. We also
update the `<kernel>_exec_mode` flag to indicate to the runtime we
changed the mode to SPMD.
The code analysis is done interprocedurally by extending the
AAKernelInfo abstract attribute to track SPMD compatibility as well.
[0] https://link.springer.com/chapter/10.1007/978-3-030-28596-8_11
Differential Revision: https://reviews.llvm.org/D102307
Broke check-clang, see https://reviews.llvm.org/D102307#2869065
Ran `git revert -n ebbe149a6f08535ede848a531a601ae6591cfbc5..269416d41908bb670f67af689155d5ab8eea689a`
In the spirit of TRegions [0], this patch analyzes a kernel and tracks
if it can be executed in SPMD-mode. If so, we flip the arguments of
the __kmpc_target_init and deinit call to enable the mode. We also
update the `<kernel>_exec_mode` flag to indicate to the runtime we
changed the mode to SPMD.
The code analysis is done interprocedurally by extending the
AAKernelInfo abstract attribute to track SPMD compatibility as well.
[0] https://link.springer.com/chapter/10.1007/978-3-030-28596-8_11
Differential Revision: https://reviews.llvm.org/D102307
While working on the elementtype attribute, I felt that the type
attribute handling in AttrBuilder is overly repetitive. This patch
converts the separate Type* members into an std::array<Type*>, so
that all type attribute kinds can be handled generically.
There's more room for improvement here (especially when it comes to
converting the AttrBuilder to an Attribute), but this seems like a
good starting point.
Differential Revision: https://reviews.llvm.org/D105658
To support options like -print-before=<pass> and -print-after=<pass>
the PassBuilder will register PassInstrumentation callbacks as well
as a mapping between internal pass class names and the pass names
used in those options (and other cmd line interfaces). But for
some reason all the passes that takes options where missing in those
maps, so for example "-print-after=loop-vectorize" didn't work.
This patch will add the missing entries by also taking care of
function and loop passes with params when setting up the class to
pass name maps.
One might notice that even with this patch it might be tricky to
know what pass name to use in options such as -print-after. This
because there only is a single mapping from class name to pass name,
while the PassRegistry currently is a bit messy as it sometimes
reuses the same class for different pass names (without using the
"pass with params" scheme, or the pass-name<variant> syntax).
It gets extra messy in some situations. For example the
MemorySanitizerPass can run like this (with debug and print-after)
opt -passes='kmsan' -print-after=msan-module -debug-only=msan
The 'kmsan' alias for 'msan<kernel>' is just confusing as one might
think that 'kmsan' is a separate pass (but the DEBUG_TYPE is still
just 'msan'). And since the module pass version of the pass adds
a mapping from 'MemorySanitizerPass' to 'msan-module' one need to
use 'msan-module' in the print-before and print-after options.
Reviewed By: ychen
Differential Revision: https://reviews.llvm.org/D105006
C++23 will make these conversions ambiguous - so fix them to make the
codebase forward-compatible with C++23 (& a follow-up change I've made
will make this ambiguous/invalid even in <C++23 so we don't regress
this & it generally improves the code anyway)
Several subclasses of User override operator new without also overriding
operator delete. This means that delete expressions fall back to using
operator delete of the base class, which would be User. However, this is
only allowed if the base class has a virtual destructor which is not the
case for User, so this is UB.
See also [expr.delete] (3) for the exact wording.
This is actually detected in some cases by GCC 11's
-Wmismatched-new-delete now which is how I found this error.
Differential Revision: https://reviews.llvm.org/D103143
Avoid enumerating all attributes here and instead use
getNameFromAttrKind(), which is based on the tablegen data.
This only leaves us with custom handling for int attributes,
which don't have uniform printing.
Same as other CreateLoad-style APIs, these need an explicit type
argument to support opaque pointers.
Differential Revision: https://reviews.llvm.org/D105395
Specifically the CreateMaskedStore and CreateMaskedScatter APIs.
The CreateMaskedLoad and CreateMaskedGather APIs will need an
additional type argument.
This reverts commit 8cd35ad854.
It breaks `TestMembersAndLocalsWithSameName.py` on GreenDragon and
Mikael Holmén points out in D104827 that bitcode files created with the
patch cannot be parsed with binaries built before it.
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
This adds support for opaque pointers in intrinsic type checks
of IIT kind Pointer and PtrToElt.
This is less straight-forward than it might initially seem, because
we should only accept opaque pointers here in --force-opaque-pointers
mode. Otherwise, there would be more than one valid type signature
for a given intrinsic name.
Differential Revision: https://reviews.llvm.org/D105155
This patch adds intrinsic definitions and SDNodes for predicated
load/store/gather/scatter, based on the work done in D57504.
Reviewed By: simoll, craig.topper
Differential Revision: https://reviews.llvm.org/D99355
Currently UREM & SREM on constant ranges produces overly pessimistic
results for single element constant ranges.
Delegate to APInt's implementation if both operands are single element
constant ranges. We already do something similar for other binary
operators, like binary AND.
Fixes PR49731.
Reviewed By: lebedev.ri
Differential Revision: https://reviews.llvm.org/D105115
Currently, LLParser will create a Function/GlobalVariable forward
reference based on the desired pointer type and then modify it when
it is declared. With opaque pointers, we generally do not know the
correct type to use until we see the declaration.
Solve this by creating the forward reference with a dummy type, and
then performing a RAUW with the correct Function/GlobalVariable when
it is declared. The approach is adopted from
b5b55963f6.
This results in a change to the use list order, which is why we see
test changes on some module passes that are not stable under use list
reordering.
Differential Revision: https://reviews.llvm.org/D104950
There can be a use after free in the Value::replaceUsesWithIf()
if two uses point to the same constant. Patch defers handling
of the constants past the iterator scan.
Another potential issue is that handleOperandChange updates all
the uses in a given Constant, not just the one passed to
ShouldReplace. Added a FIXME comment.
Both issues are not currently exploitable as the only use of
this call with constants avoids it.
Differential Revision: https://reviews.llvm.org/D105061
Add UNIQUED and DISTINCT properties in Metadata.def and use them to
implement restrictions on the `distinct` property of MDNodes:
* DIExpression can currently be parsed from IR or read from bitcode
as `distinct`, but this property is silently dropped when printing
to IR. This causes accepted IR to fail to round-trip. As DIExpression
appears inline at each use in the canonical form of IR, it cannot
actually be `distinct` anyway, as there is no syntax to describe it.
* Similarly, DIArgList is conceptually always uniqued. It is currently
restricted to only appearing in contexts where there is no syntax for
`distinct`, but for consistency it is treated equivalently to
DIExpression in this patch.
* DICompileUnit is already restricted to always being `distinct`, but
along with adding general support for the inverse restriction I went
ahead and described this in Metadata.def and updated the parser to be
general. Future nodes which have this restriction can share this
support.
The new UNIQUED property applies to DIExpression and DIArgList, and
forbids them to be `distinct`. It also implies they are canonically
printed inline at each use, rather than via MDNode ID.
The new DISTINCT property applies to DICompileUnit, and requires it to
be `distinct`.
A potential alternative change is to forbid the non-inline syntax for
DIExpression entirely, as is done with DIArgList implicitly by requiring
it appear in the context of a function. For example, we would forbid:
!named = !{!0}
!0 = !DIExpression()
Instead we would only accept the equivalent inlined version:
!named = !{!DIExpression()}
This essentially removes the ability to create a `distinct` DIExpression
by construction, as there is no syntax for `distinct` inline. If this
patch is accepted as-is, the result would be that the non-canonical
version is accepted, but the following would be an error and produce a diagnostic:
!named = !{!0}
; error: 'distinct' not allowed for !DIExpression()
!0 = distinct !DIExpression()
Also update some documentation to consistently use the inline syntax for
DIExpression, and to describe the restrictions on `distinct` for nodes
where applicable.
Reviewed By: StephenTozer, t-tye
Differential Revision: https://reviews.llvm.org/D104827
Currently, AsmWriter will stick uselistorder directives for global
values inside individual functions. This doesn't make a lot of sense,
and interacts badly with D104950, as use list order adjustments will
be performed while still working on a forward reference.
This patch instead always prints uselistorder directives for globals
at the module level. This isn't really compatible with the previously
used implementation approach. Rather than walking through all values
again, use the OrderMap (after stabilizing its order) to go through
all values and compute the use list shuffles for them. Classify them
per-function, or nullptr for globals.
Even independently of D104950, this seems to fix a few
verify-uselistorder failures. Conveniently, there is even a
pre-existing failing test that this fixes.
Differential Revision: https://reviews.llvm.org/D104976
I added an assertion in D91816 (documenting behavior added in D93422)
that callers and callees with mismatched fn attr's related to stack
protectors should not occur unless the callee was attributed
always_inline.
This falls apart when a call, invoke, or callbr (any instruction
inheriting from CallBase) itself has an always_inline attribute. Clang
will emit such attributes on Instructions when __attribute__((flatten))
is used to recursively force inlining from a caller.
Since these assertions only had the caller and callee Functions, and not
the call site (CallBase derived classes), we would have to search the
caller for such instructions to reconstruct the call site information.
But at that point, inlining has already occurred; the call site has
already been removed from the caller.
Remove the assertions, add a unit test for always_inline call sites, and
update the LangRef.
Another curiosity is that the always_inline Attribute on Instructions is
only expanded by the inline pass, not the always_inline pass.
Thanks to @pcc on this report when building Android's RunTime (ART)
interpreter.
Reviewed By: pcc, MaskRay
Differential Revision: https://reviews.llvm.org/D104944
Fix the use-list-order for br instructions by setting the operands in
order of their index to match the use-list-order prediction. The case
where this matters is when there is a condition but the if-true and
if-false branches are identical.
Bug was found when reviewing failures pointed at by
https://reviews.llvm.org/D104950. Fix is similar to
3cf415c6c3.
Differential Revision: https://reviews.llvm.org/D104959
the call's return type is void
Instead of trying hard to prevent global optimization passes such as
deadargelim from changing the return type to void, just ignore the
bundle if the return type is void. clang currently emits calls to
@llvm.objc.clang.arc.noop.use, which consumes the function call result,
immediately after the function call to prevent changes to the return
type, but optimization passes can delete the call to
@llvm.objc.clang.arc.noop.use if the function call doesn't return, which
enables deadargelim to change the return type.
rdar://76671438
Differential Revision: https://reviews.llvm.org/D103062
Do this by making opaque pointers a valid pointer element type,
for which we implicitly create an opaque pointer (moving the logic
from getPointerTo into PointerType::get).
We'll never create something like a "pointer to opaque pointer",
but accept it in the API, because a lot of code reasonably assumes
that you can create a pointer to pointer type.
Differential Revision: https://reviews.llvm.org/D104902
We don't want to start updating tests to use opaque pointers until we're
close to the opaque pointer transition. However, before the transition
we want to run tests as if pointers are opaque pointers to see if there
are any crashes.
At some point when we have a flag to only create opaque pointers in the
bitcode and textual IR readers, and when we have fixed all places that
try to read a pointee type, this flag will be useless. However, until
then, this can help us find issues more easily.
Since the cl::opt is read into LLVMContext, we need to make sure
LLVMContext is created after cl::ParseCommandLineOptions().
Previously ValueEnumerator would visit the value types of global values
via the pointer type, but with opaque pointers we have to manually visit
the value type.
Reviewed By: nikic, dexonsmith
Differential Revision: https://reviews.llvm.org/D103503
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 386b66b2fc.
Fix the use-list-order for call and invoke instructions by setting the
operands in order of their index. This matches the use-list-order
prediction. Note that the verifier precludes sharing operands in callbr
(so there was no bug to fix), but that code was updated for consistency.
Bug was found during review of https://reviews.llvm.org/D104740.
Differential Revision: https://reviews.llvm.org/D104805
Add support for call of opaque pointer, currently only possible for
indirect calls.
This requires a bit of special casing in LLParser, as calls do not
specify the callee operand type explicitly.
Differential Revision: https://reviews.llvm.org/D104740
With regards to overrunning, the langref (llvm/docs/LangRef.rst)
specifies:
(llvm.experimental.vector.insert)
Elements ``idx`` through (``idx`` + num_elements(``subvec``) - 1)
must be valid ``vec`` indices. If this condition cannot be determined
statically but is false at runtime, then the result vector is
undefined.
(llvm.experimental.vector.extract)
Elements ``idx`` through (``idx`` + num_elements(result_type) - 1)
must be valid vector indices. If this condition cannot be determined
statically but is false at runtime, then the result vector is
undefined.
For the non-mixed cases (e.g. inserting/extracting a scalable into/from
another scalable, or inserting/extracting a fixed into/from another
fixed), it is possible to statically check whether or not the above
conditions are met. This was previously missing from the verifier, and
if the conditions were found to be false, the result of the
insertion/extraction would be replaced with an undef.
With regards to invalid indices, the langref (llvm/docs/LangRef.rst)
specifies:
(llvm.experimental.vector.insert)
``idx`` represents the starting element number at which ``subvec``
will be inserted. ``idx`` must be a constant multiple of
``subvec``'s known minimum vector length.
(llvm.experimental.vector.extract)
The ``idx`` specifies the starting element number within ``vec``
from which a subvector is extracted. ``idx`` must be a constant
multiple of the known-minimum vector length of the result type.
Similarly, these conditions were not previously enforced in the
verifier. In some circumstances, invalid indices were permitted
silently, and in other circumstances, an undef was spawned where a
verifier error would have been preferred.
This commit adds verifier checks to enforce the constraints above.
Differential Revision: https://reviews.llvm.org/D104468
NFCI, although the test change shows that ConstantExpr::getAsInstruction
is better than the old implementation of createReplacementInstr because
it propagates things like the sdiv "exact" flag.
Differential Revision: https://reviews.llvm.org/D104124
When the load type is changed to ptr, we need the load pointer type
to also be ptr, because it's not allowed to create a pointer to an
opaque pointer. This is achieved by adjusting the getPointerTo() API
to return an opaque pointer for an opaque pointer base type.
Differential Revision: https://reviews.llvm.org/D104718
This adds support for addrspace casts involving opaque pointers to
InstCombine, as well as the isEliminableCastPair() helper
(otherwise the assertion failure would just move there).
Add PointerType::hasSameElementTypeAs() to hide the element type
details.
Differential Revision: https://reviews.llvm.org/D104668
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
- Distinct metadata needs generating in the codegen to attach correct
AAInfo on the loads/stores after lowering, merging, and other relevant
transformations.
- This patch adds 'MachhineModuleSlotTracker' to help assign slot
numbers to these newly generated unnamed metadata nodes.
- To help 'MachhineModuleSlotTracker' track machine metadata, the
original 'SlotTracker' is rebased from 'AbstractSlotTrackerStorage',
which provides basic interfaces to create/retrive metadata slots. In
addition, once LLVM IR is processsed, additional hooks are also
introduced to help collect machine metadata and assign them slot
numbers.
- Finally, if there is any such machine metadata, 'MIRPrinter' outputs
an additional 'machineMetadataNodes' field containing all the
definition of those nodes.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D103205
As a follow-up to https://reviews.llvm.org/D104129, I'm cleaning up the danling probe related code in both the compiler and llvm-profgen.
I'm seeing a 5% size win for the pseudo_probe section for SPEC2017 and 10% for Ciner. Certain benchmark such as 602.gcc has a 20% size win. No obvious difference seen on build time for SPEC2017 and Cinder.
Reviewed By: wenlei
Differential Revision: https://reviews.llvm.org/D104477
When LLVM is used in other projects, it may happen that global cons-
tructors will execute before the call to ParseCommandLineOptions.
Since OptBisect is initialized via a constructor, and has no ability
to be updated at a later time, passing "-opt-bisect-limit" to the
parse function may have no effect.
To avoid this problem use a cl::cb (callback) to set the bisection
limit when the option is actually processed.
Differential Revision: https://reviews.llvm.org/D104551
Reapply the commit which previously caused build failures due to the
mismatched template arguments between the return type and the returned
SmallVector.
This reverts commit e8991caea8.
This patch fixes an issue where builds of programs with multiple dbg.values
with DIArgList locations could have non-deterministic output. This issue
was caused by ReplaceableMetadataImpl::getAllArgListUsers, which
returned DIArgList pointers in a random order; the output of this
function would later be used to insert dbg.values, causing the order of
insertion to be non-deterministic. This patch changes getAllArgListUsers
to return pointers in a fixed order.
Differential Revision: https://reviews.llvm.org/D104105
Recently added convertConstantExprsToInstructions() does not handle
a case when a same ConstantExpr used multiple times in the same
instruction. A first use is replaced and the rest of the uses in the
instruction are replaced as well with the replaceUsesOfWith(). Then
function attempts to replace a constant already destroyed.
So far this interface is only used by the AMDGPU BE.
Differential Revision: https://reviews.llvm.org/D104425
Verifying opaque pointer as function parameter when using with `byval`, `byref`,
`inalloca`, `preallocated`.
Differential Revision: https://reviews.llvm.org/D104309
Ensure that we provide a `Module` when checking if a rename of an intrinsic is necessary.
This fixes the issue that was detected by https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=32288
(as mentioned by @fhahn), after committing D91250.
Note that the `LLVMIntrinsicCopyOverloadedName` is being deprecated in favor of `LLVMIntrinsicCopyOverloadedName2`.
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D99173
I don't like landing this change, but it's an acknowledgement of a practical reality. Despite not having well specified semantics for inttoptr and ptrtoint involving non-integral pointer types, they are used in practice. Here's a quick summary of the current pragmatic reality:
* I happen to know that the main external user of non-integral pointers has effectively disabled the verifier rules.
* RS4GC (the lowering pass for abstract GC machine model which is the key motivation for non-integral pointers), even supports them. We just have all the tests using an integral pointer space to let the verifier run.
* Certain idioms (such as alignment checks for alignment N, where any relocation is guaranteed to be N byte aligned) are fine in practice.
* As implemented, inttoptr/ptrtoint are CSEd and are not control dependent. This means that any code which is intending to check a particular bit pattern at site of use must be wrapped in an intrinsic or external function call.
This change allows them in the Verifier, and updates the LangRef to specific them as implementation dependent. This allows us to acknowledge current reality while still leaving ourselves room to punt on figuring out "good" semantics until the future.
Value::SubclassID cannot be directly compared to Instruction enums, such as
Instruction::{Call,Invoke,CallBr}. We have to first subtract InstructionVal
from the SubclassID to get the OpCode, similar to Instruction::getOpCode().
Reviewed By: nickdesaulniers
Differential Revision: https://reviews.llvm.org/D104043
-Wframe-larger-than= is an interesting warning; we can't know the frame
size until PrologueEpilogueInsertion (PEI); very late in the compilation
pipeline.
-Wframe-larger-than= was propagated through CC1 as an -mllvm flag, then
was a cl::opt in LLVM's PEI pass; this meant it was dropped during LTO
and needed to be re-specified via -plugin-opt.
Instead, make it part of the IR proper as a module level attribute,
similar to D103048. Introduce -fwarn-stack-size CC1 option.
Reviewed By: rsmith, qcolombet
Differential Revision: https://reviews.llvm.org/D103928
This patch allows that scalable vector can fold extractelement and constant splat
only when the lane index is lower than the minimum number of elements of the vector.
Differential Revision: https://reviews.llvm.org/D103180
> 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 36ec97f76a.
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
a0bd6105d8.
`VPIntrinsic::getDeclarationForParams` creates a vp intrinsic
declaration for parameters you want to call it with. This is in
preparation of a new builder class that makes emitting vp intrinsic code
nearly as convenient as using a plain ir builder (aka `VectorBuilder`,
to be used by D99750).
Reviewed By: frasercrmck, craig.topper, vkmr
Differential Revision: https://reviews.llvm.org/D102686
In the situation where we need to replace a constant operand C from a constant expression CE
by an instruction NI, it not possible without converting CE itself into an instruction. This
utility helps to convert the given set of constant expression operands from an instruction I
into a corresponding set of instructions.
The current use-case for this utility is from the patches - https://reviews.llvm.org/D103225
and https://reviews.llvm.org/D103655.
Reviewed By: rampitec
Differential Revision: https://reviews.llvm.org/D103661
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
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
InstCombine didn't perform the transformations when fmul's operands were
the same instruction because it required to have one use for each of them
which is false in the case. This patch fixes this + adds tests for them
and introduces a new function isOnlyUserOfAnyOperand to check these cases
in a single place.
This patch is a result of discussion in D102574.
Differential Revision: https://reviews.llvm.org/D102698
Parameter positions seem like they should be unsigned.
While there, make function names lowercase per coding standards.
Reviewed By: frasercrmck
Differential Revision: https://reviews.llvm.org/D103224
TypeFinder did not find types under DIArgList. This resulted in a case
of invalid IR after GlobalOpt removed a global that was the only
non-DIArgList use of a struct type.
error: use of undefined type named 'struct.S'
call void @llvm.dbg.value(
metadata !DIArgList([1 x %struct.S]* undef, i64 %idxprom),
metadata !24, metadata !DIExpression([...]))
Reviewed By: jmorse
Differential Revision: https://reviews.llvm.org/D103306
SwiftTailCC has a different set of requirements than the C calling convention
for a tail call. The exact argument sequence doesn't have to match, but fewer
ABI-affecting attributes are allowed.
Also make sure the musttail diagnostic triggers if a musttail call isn't
actually a tail call.
in stripDebugInfo(). This patch fixes an oversight in
https://reviews.llvm.org/D96181 and also takes into account loop
metadata pointing to other MDNodes that point into the debug info.
rdar://78487175
Differential Revision: https://reviews.llvm.org/D103220
`non-global-value-max-name-size` is used by `Value` to cap the length of local value name. However, this flag is not considered by `LLParser`, which leads to unexpected `use of undefined value error`. The fix is to move the responsibility of capping the length to `ValueSymbolTable`.
The test is the one provided by [[ https://bugs.llvm.org/show_bug.cgi?id=45899 | Mikael in the bug report ]].
Reviewed By: mehdi_amini
Differential Revision: https://reviews.llvm.org/D102707
There can be a need for some optimizations to get (base, offset)
for any GC pointer. The base can be calculated by generating
needed instructions as it is done by the
RewriteStatepointsForGC::findBasePointer() function. The offset
can be calculated in the same way. Though to not expose the base
calculation and to make the offset calculation as simple as
ptrtoint(derived_ptr) - ptrtoint(base_ptr), which is illegal
outside RS4GC, this patch introduces 2 intrinsics:
@llvm.experimental.gc.get.pointer.base(%derived_ptr)
@llvm.experimental.gc.get.pointer.offset(%derived_ptr)
These intrinsics are inlined by RS4GC along with generation of
statepoint sequences.
With these new intrinsics the GC parseable lowering for atomic
memcpy intrinsics (6ec2c5e402)
could be implemented as a separate pass.
Reviewed By: reames
Differential Revision: https://reviews.llvm.org/D100445
FullTy is only necessary when we need to figure out what type an
instruction works with given a pointer's pointee type. However, we just
end up using the value operand's type, so FullTy isn't necessary.
Reviewed By: dblaikie
Differential Revision: https://reviews.llvm.org/D102788
We really ought to support no_sanitize("coverage") in line with other
sanitizers. This came up again in discussions on the Linux-kernel
mailing lists, because we currently do workarounds using objtool to
remove coverage instrumentation. Since that support is only on x86, to
continue support coverage instrumentation on other architectures, we
must support selectively disabling coverage instrumentation via function
attributes.
Unfortunately, for SanitizeCoverage, it has not been implemented as a
sanitizer via fsanitize= and associated options in Sanitizers.def, but
rolls its own option fsanitize-coverage. This meant that we never got
"automatic" no_sanitize attribute support.
Implement no_sanitize attribute support by special-casing the string
"coverage" in the NoSanitizeAttr implementation. To keep the feature as
unintrusive to existing IR generation as possible, define a new negative
function attribute NoSanitizeCoverage to propagate the information
through to the instrumentation pass.
Fixes: https://bugs.llvm.org/show_bug.cgi?id=49035
Reviewed By: vitalybuka, morehouse
Differential Revision: https://reviews.llvm.org/D102772
The change is currently NFC, but exploited by the depending D102954.
Code to handle constants is borrowed from the general implementation
of Value::doRAUW().
Differential Revision: https://reviews.llvm.org/D103051
When removing an AttrBuilder from an AttributeSet, first check
whether there is any overlap. If nothing is being removed, we can
directly return the original set.
D88631 added initial support for:
- -mstack-protector-guard=
- -mstack-protector-guard-reg=
- -mstack-protector-guard-offset=
flags, and D100919 extended these to AArch64. Unfortunately, these flags
aren't retained for LTO. Make them module attributes rather than
TargetOptions.
Link: https://github.com/ClangBuiltLinux/linux/issues/1378
Reviewed By: tejohnson
Differential Revision: https://reviews.llvm.org/D102742
These checks already exist as asserts when creating the corresponding
instruction. Anybody creating these instructions already need to take
care to not break these checks.
Move the checks for success/failure ordering in cmpxchg from the
verifier to the LLParser and BitcodeReader plus an assert.
Add some tests for cmpxchg ordering. The .bc files are created from the
.ll files with an llvm-as with these checks disabled.
Reviewed By: dblaikie
Differential Revision: https://reviews.llvm.org/D102803
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 4397b7095d.
In the WebAssembly target, we would like to allow alloca in two address
spaces. The alloca instruction already has an address space argument,
but the verifier asserts that the address space of an alloca is the
default alloca address space from the datalayout. This patch removes
this restriction. Targets that would like to impose additional
restrictions should do so via target-specific verification passes.
Differential Revision: https://reviews.llvm.org/D101045
Previously APFloat::convertToDouble may be called only for APFloats that
were built using double semantics. Other semantics like single precision
were not allowed although corresponding numbers could be converted to
double without loss of precision. The similar restriction applied to
APFloat::convertToFloat.
With this change any APFloat that can be precisely represented by double
can be handled with convertToDouble. Behavior of convertToFloat was
updated similarly. It make the conversion operations more convenient and
adds support for formats like half and bfloat.
Differential Revision: https://reviews.llvm.org/D102671
EarlyCSE cannot distinguish between floating point instructions and
constrained floating point intrinsics that are marked as running in the
default FP environment. Said intrinsics are supposed to behave exactly the
same as the regular FP instructions. Teach EarlyCSE to handle them in that
case.
Differential Revision: https://reviews.llvm.org/D99962
This is a follow-up of D102201. After some discussion, it is a better idea
to upgrade all invalid uses of alignment attributes on function return
values and parameters, not just limited to void function return types.
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D102726
FullTy is only necessary when we need to figure out what type an
instruction works with given a pointer's pointee type. However, we just
end up using the value operand's type, so FullTy isn't necessary.
Reviewed By: dblaikie
Differential Revision: https://reviews.llvm.org/D102788
Summary:
Currently, only `OptimizationRemarks` can be emitted using a Function.
Add constructors to allow this for `OptimizationRemarksAnalysis` and
`OptimizationRemarkMissed` as well.
Reviewed By: jdoerfert thegameg
Differential Revision: https://reviews.llvm.org/D102784
The operation of some VP intrinsics do/will not map to regular
instruction opcodes. Returning 'None' seems more intuitive here than
'Instruction::Call'.
Reviewed By: frasercrmck
Differential Revision: https://reviews.llvm.org/D102778
This patch implements first part of Flow Sensitive SampleFDO (FSAFDO).
It has the following changes:
(1) disable current discriminator encoding scheme,
(2) new hierarchical discriminator for FSAFDO.
For this patch, option "-enable-fs-discriminator=true" turns on the new
functionality. Option "-enable-fs-discriminator=false" (the default)
keeps the current SampleFDO behavior. When the fs-discriminator is
enabled, we insert a flag variable, namely, llvm_fs_discriminator, to
the object. This symbol will checked by create_llvm_prof tool, and used
to generate a profile with FS-AFDO discriminators enabled. If this
happens, for an extbinary format profile, create_llvm_prof tool
will add a flag to profile summary section.
Differential Revision: https://reviews.llvm.org/D102246
Don't check that types match when the pointer operand is an opaque
pointer.
I would separate the Assembler and Verifier changes, but
verify-uselistorder in the Assembler test ends up running the verifier.
Reviewed By: dblaikie
Differential Revision: https://reviews.llvm.org/D102450
This patch is the Part-1 (FE Clang) implementation of HW Exception handling.
This new feature adds the support of Hardware Exception for Microsoft Windows
SEH (Structured Exception Handling).
This is the first step of this project; only X86_64 target is enabled in this patch.
Compiler options:
For clang-cl.exe, the option is -EHa, the same as MSVC.
For clang.exe, the extra option is -fasync-exceptions,
plus -triple x86_64-windows -fexceptions and -fcxx-exceptions as usual.
NOTE:: Without the -EHa or -fasync-exceptions, this patch is a NO-DIFF change.
The rules for C code:
For C-code, one way (MSVC approach) to achieve SEH -EHa semantic is to follow
three rules:
* First, no exception can move in or out of _try region., i.e., no "potential
faulty instruction can be moved across _try boundary.
* Second, the order of exceptions for instructions 'directly' under a _try
must be preserved (not applied to those in callees).
* Finally, global states (local/global/heap variables) that can be read
outside of _try region must be updated in memory (not just in register)
before the subsequent exception occurs.
The impact to C++ code:
Although SEH is a feature for C code, -EHa does have a profound effect on C++
side. When a C++ function (in the same compilation unit with option -EHa ) is
called by a SEH C function, a hardware exception occurs in C++ code can also
be handled properly by an upstream SEH _try-handler or a C++ catch(...).
As such, when that happens in the middle of an object's life scope, the dtor
must be invoked the same way as C++ Synchronous Exception during unwinding
process.
Design:
A natural way to achieve the rules above in LLVM today is to allow an EH edge
added on memory/computation instruction (previous iload/istore idea) so that
exception path is modeled in Flow graph preciously. However, tracking every
single memory instruction and potential faulty instruction can create many
Invokes, complicate flow graph and possibly result in negative performance
impact for downstream optimization and code generation. Making all
optimizations be aware of the new semantic is also substantial.
This design does not intend to model exception path at instruction level.
Instead, the proposed design tracks and reports EH state at BLOCK-level to
reduce the complexity of flow graph and minimize the performance-impact on CPP
code under -EHa option.
One key element of this design is the ability to compute State number at
block-level. Our algorithm is based on the following rationales:
A _try scope is always a SEME (Single Entry Multiple Exits) region as jumping
into a _try is not allowed. The single entry must start with a seh_try_begin()
invoke with a correct State number that is the initial state of the SEME.
Through control-flow, state number is propagated into all blocks. Side exits
marked by seh_try_end() will unwind to parent state based on existing
SEHUnwindMap[].
Note side exits can ONLY jump into parent scopes (lower state number).
Thus, when a block succeeds various states from its predecessors, the lowest
State triumphs others. If some exits flow to unreachable, propagation on those
paths terminate, not affecting remaining blocks.
For CPP code, object lifetime region is usually a SEME as SEH _try.
However there is one rare exception: jumping into a lifetime that has Dtor but
has no Ctor is warned, but allowed:
Warning: jump bypasses variable with a non-trivial destructor
In that case, the region is actually a MEME (multiple entry multiple exits).
Our solution is to inject a eha_scope_begin() invoke in the side entry block to
ensure a correct State.
Implementation:
Part-1: Clang implementation described below.
Two intrinsic are created to track CPP object scopes; eha_scope_begin() and eha_scope_end().
_scope_begin() is immediately added after ctor() is called and EHStack is pushed.
So it must be an invoke, not a call. With that it's also guaranteed an
EH-cleanup-pad is created regardless whether there exists a call in this scope.
_scope_end is added before dtor(). These two intrinsics make the computation of
Block-State possible in downstream code gen pass, even in the presence of
ctor/dtor inlining.
Two intrinsic, seh_try_begin() and seh_try_end(), are added for C-code to mark
_try boundary and to prevent from exceptions being moved across _try boundary.
All memory instructions inside a _try are considered as 'volatile' to assure
2nd and 3rd rules for C-code above. This is a little sub-optimized. But it's
acceptable as the amount of code directly under _try is very small.
Part-2 (will be in Part-2 patch): LLVM implementation described below.
For both C++ & C-code, the state of each block is computed at the same place in
BE (WinEHPreparing pass) where all other EH tables/maps are calculated.
In addition to _scope_begin & _scope_end, the computation of block state also
rely on the existing State tracking code (UnwindMap and InvokeStateMap).
For both C++ & C-code, the state of each block with potential trap instruction
is marked and reported in DAG Instruction Selection pass, the same place where
the state for -EHsc (synchronous exceptions) is done.
If the first instruction in a reported block scope can trap, a Nop is injected
before this instruction. This nop is needed to accommodate LLVM Windows EH
implementation, in which the address in IPToState table is offset by +1.
(note the purpose of that is to ensure the return address of a call is in the
same scope as the call address.
The handler for catch(...) for -EHa must handle HW exception. So it is
'adjective' flag is reset (it cannot be IsStdDotDot (0x40) that only catches
C++ exceptions).
Suppress push/popTerminate() scope (from noexcept/noTHrow) so that HW
exceptions can be passed through.
Original llvm-dev [RFC] discussions can be found in these two threads below:
https://lists.llvm.org/pipermail/llvm-dev/2020-March/140541.htmlhttps://lists.llvm.org/pipermail/llvm-dev/2020-April/141338.html
Differential Revision: https://reviews.llvm.org/D80344/new/
Adding lowering support for bitreverse.
Previously, lowering bitreverse would expand it into a series of other instructions. This patch makes it so this produces a single rbit instruction instead.
Reviewed By: dmgreen
Differential Revision: https://reviews.llvm.org/D102397
Swift's new concurrency features are going to require guaranteed tail calls so
that they don't consume excessive amounts of stack space. This would normally
mean "tailcc", but there are also Swift-specific ABI desires that don't
naturally go along with "tailcc" so this adds another calling convention that's
the combination of "swiftcc" and "tailcc".
Support is added for AArch64 and X86 for now.
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
This extends any frame record created in the function to include that
parameter, passed in X22.
The new record looks like [X22, FP, LR] in memory, and FP is stored with 0b0001
in bits 63:60 (CodeGen assumes they are 0b0000 in normal operation). The effect
of this is that tools walking the stack should expect to see one of three
values there:
* 0b0000 => a normal, non-extended record with just [FP, LR]
* 0b0001 => the extended record [X22, FP, LR]
* 0b1111 => kernel space, and a non-extended record.
All other values are currently reserved.
If compiling for arm64e this context pointer is address-discriminated with the
discriminator 0xc31a and the DB (process-specific) key.
There is also an "i8** @llvm.swift.async.context.addr()" intrinsic providing
front-ends access to this slot (and forcing its creation initialized to nullptr
if necessary).
The opaque pointer type is essentially just a normal pointer type with a
null pointee type.
This also adds support for the opaque pointer type to the bitcode
reader/writer, as well as to textual IR.
To avoid confusion with existing pointer types, we disallow creating a
pointer to an opaque pointer.
Opaque pointer types should not be widely used at this point since many
parts of LLVM still do not support them. The next steps are to add some
very simple use cases of opaque pointers to make sure they work, then
start pretending that all pointers are opaque pointers and see what
breaks.
https://lists.llvm.org/pipermail/llvm-dev/2021-May/150359.html
Reviewed By: dblaikie, dexonsmith, pcc
Differential Revision: https://reviews.llvm.org/D101704
I've taken the following steps to add unwinding support from inline assembly:
1) Add a new `unwind` "attribute" (like `sideeffect`) to the asm syntax:
```
invoke void asm sideeffect unwind "call thrower", "~{dirflag},~{fpsr},~{flags}"()
to label %exit unwind label %uexit
```
2.) Add Bitcode writing/reading support + LLVM-IR parsing.
3.) Emit EHLabels around inline assembly lowering (SelectionDAGBuilder + GlobalISel) when `InlineAsm::canThrow` is enabled.
4.) Tweak InstCombineCalls/InlineFunction pass to not mark inline assembly "calls" as nounwind.
5.) Add clang support by introducing a new clobber: "unwind", which lower to the `canThrow` being enabled.
6.) Don't allow unwinding callbr.
Reviewed By: Amanieu
Differential Revision: https://reviews.llvm.org/D95745
This was reverted to mitigate mitigate miscompiles caused by
the logical and/or to bitwise and/or fold. Reapply it now that
the underlying issue has been fixed by D101191.
-----
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
We want it to be available in analyzes so that we could use the
CodeGen notion in middle-end passes (for example, to check if
a GC may free some particular pointer).
This is a preparatory patch that simply moves the files around.
Note: if this causes some build issues, this patch must just be reverted.
Differential Revision: https://reviews.llvm.org/D100557
Reviewed By: reames
Since D87304, `align` become an invalid attribute on none pointer types and
verifier will reject bitcode that has invalid `align` attribute.
The problem is before the change, DeadArgumentElimination can easily
turn a pointer return type into a void return type without removing
`align` attribute. Teach Autograde to remove invalid `align` attribute
from return types to maintain bitcode compatibility.
rdar://77022993
Reviewed By: dexonsmith
Differential Revision: https://reviews.llvm.org/D102201
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
Follow up on 431e3138a and complete the other possible combinations.
Besides enforcing the new behavior, it also mitigates TSAN false positives when
combining orders that used to be stronger.
Adds support for scalable vectorization of loops containing first-order recurrences, e.g:
```
for(int i = 0; i < n; i++)
b[i] = a[i] + a[i - 1]
```
This patch changes fixFirstOrderRecurrence for scalable vectors to take vscale into
account when inserting into and extracting from the last lane of a vector.
CreateVectorSplice has been added to construct a vector for the recurrence, which
returns a splice intrinsic for scalable types. For fixed-width the behaviour
remains unchanged as CreateVectorSplice will return a shufflevector instead.
The tests included here are the same as test/Transform/LoopVectorize/first-order-recurrence.ll
Reviewed By: david-arm, fhahn
Differential Revision: https://reviews.llvm.org/D101076
When auto-upgrade was replacing a call to a masked intrinsic, it would
not copy the metadata from the original call.
If an intrinsic had metadata, but did not need any updates, the metadata
would stay, but if an update was needed, the would end up being removed.
A similar effect could be observed with masked_expandload and
masked_compressstore, which at the moment are not handled by auto-upgrade:
the metadata remained untouched.
Differential Revision: https://reviews.llvm.org/D101201
This reverts the revert 02c5ba8679
Fix:
Pass was registered as DUMMY_FUNCTION_PASS causing the newpm-pass
functions to be doubly defined. Triggered in -DLLVM_ENABLE_MODULE=1
builds.
Original commit:
This patch implements expansion of llvm.vp.* intrinsics
(https://llvm.org/docs/LangRef.html#vector-predication-intrinsics).
VP expansion is required for targets that do not implement VP code
generation. Since expansion is controllable with TTI, targets can switch
on the VP intrinsics they do support in their backend offering a smooth
transition strategy for VP code generation (VE, RISC-V V, ARM SVE,
AVX512, ..).
Reviewed By: rogfer01
Differential Revision: https://reviews.llvm.org/D78203
As opposed to going through the Aliasee type.
For opaque pointers, we're trying to remove uses of PointerType::getElementType().
Reviewed By: dblaikie
Differential Revision: https://reviews.llvm.org/D101715
This patch implements expansion of llvm.vp.* intrinsics
(https://llvm.org/docs/LangRef.html#vector-predication-intrinsics).
VP expansion is required for targets that do not implement VP code
generation. Since expansion is controllable with TTI, targets can switch
on the VP intrinsics they do support in their backend offering a smooth
transition strategy for VP code generation (VE, RISC-V V, ARM SVE,
AVX512, ..).
Reviewed By: rogfer01
Differential Revision: https://reviews.llvm.org/D78203
Value only used by metadata can be removed from .addrsig table.
This solves the undefined symbol error when enabling addrsig table on COFF LTO.
Differential Revision: https://reviews.llvm.org/D101512
verifyFunctionAttrs has a comment that the value V is printed in error messages. The recently added errors for attributes didn't print V. Make them print V.
Change the stringification of AttributeList. Firstly they started with 'PAL[' which stood for ParamAttrsList. Change that to 'AttributeList[' matching its current name AttributeList. Print out semantic meaning of the index instead of the raw index value (i.e. 'return', 'function' or 'arg(n)').
Differential revision: https://reviews.llvm.org/D101484
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 dad5caa59e.
The Linux kernel objtool diagnostic `call without frame pointer save/setup`
arise in multiple instrumentation passes (asan/tsan/gcov). With the mechanism
introduced in D100251, it's trivial to respect the command line
-m[no-]omit-leaf-frame-pointer/-f[no-]omit-frame-pointer, so let's do it.
Fix: https://github.com/ClangBuiltLinux/linux/issues/1236 (tsan)
Fix: https://github.com/ClangBuiltLinux/linux/issues/1238 (asan)
Also document the function attribute "frame-pointer" which is long overdue.
Differential Revision: https://reviews.llvm.org/D101016
In quite a few cases in LoopVectorize.cpp we call createStepForVF
with a step value of 0, which leads to unnecessary generation of
llvm.vscale intrinsic calls. I've optimised IRBuilder::CreateVScale
and createStepForVF to return 0 when attempting to multiply
vscale by 0.
Differential Revision: https://reviews.llvm.org/D100763
On ELF targets, if a function has uwtable or personality, or does not have
nounwind (`needsUnwindTableEntry`), it marks that `.eh_frame` is needed in the module.
Then, a function gets `.eh_frame` if `needsUnwindTableEntry` or `-g[123]` is specified.
(i.e. If -g[123], every function gets `.eh_frame`.
This behavior is strange but that is the status quo on GCC and Clang.)
Let's take asan as an example. Other sanitizers are similar.
`asan.module_[cd]tor` has no attribute. `needsUnwindTableEntry` returns true,
so every function gets `.eh_frame` if `-g[123]` is specified.
This is the root cause that
`-fno-exceptions -fno-asynchronous-unwind-tables -g` produces .debug_frame
while
`-fno-exceptions -fno-asynchronous-unwind-tables -g -fsanitize=address` produces .eh_frame.
This patch
* sets the nounwind attribute on sanitizer module ctor/dtor.
* let Clang emit a module flag metadata "uwtable" for -fasynchronous-unwind-tables. If "uwtable" is set, sanitizer module ctor/dtor additionally get the uwtable attribute.
The "uwtable" mechanism is generic: synthesized functions not cloned/specialized
from existing ones should consider `Function::createWithDefaultAttr` instead of
`Function::create` if they want to get some default attributes which
have more of module semantics.
Other candidates: "frame-pointer" (https://github.com/ClangBuiltLinux/linux/issues/955https://github.com/ClangBuiltLinux/linux/issues/1238), dso_local, etc.
Differential Revision: https://reviews.llvm.org/D100251
This patch is related to https://reviews.llvm.org/D100032 which define
some illegal types or operations for x86_amx. There are no arguments,
arrays, pointers, vectors or constants of x86_amx.
Reviewed By: pengfei
Differential Revision: https://reviews.llvm.org/D100472
Value::replaceUsesOutsideBlock doesn't replace debug uses which leads to an
unnecessary reduction in variable location coverage. Fix this, add a unittest for
it, and add a regression test demonstrating the change through instcombine's
replacedSelectWithOperand.
Reviewed By: djtodoro
Differential Revision: https://reviews.llvm.org/D99169
Move the findDbg* functions into lib/IR/DebugInfo.cpp from
lib/Transforms/Utils/Local.cpp.
D99169 adds a call to a function (findDbgUsers) that lives in
lib/Transforms/Utils/Local.cpp (LLVMTransformUtils) from lib/IR/Value.cpp
(LLVMCore). The Core lib doesn't include TransformUtils. The builtbots caught
this here: https://lab.llvm.org/buildbot/#/builders/109/builds/12664. This patch
moves the function, and the 3 similar ones for consistency, into DebugInfo.cpp
which is part of LLVMCore.
Reviewed By: dblaikie, rnk
Differential Revision: https://reviews.llvm.org/D100632
Such attributes can either be unset, or set to "true" or "false" (as string).
throughout the codebase, this led to inelegant checks ranging from
if (Fn->getFnAttribute("no-jump-tables").getValueAsString() == "true")
to
if (Fn->hasAttribute("no-jump-tables") && Fn->getFnAttribute("no-jump-tables").getValueAsString() == "true")
Introduce a getValueAsBool that normalize the check, with the following
behavior:
no attributes or attribute set to "false" => return false
attribute set to "true" => return true
Differential Revision: https://reviews.llvm.org/D99299
This patch clarifies the semantics of the nofree function attribute to make clear that it provides an "as if" semantic. That is, a nofree function is guaranteed not to free memory which existed before the call, but might allocate and then deallocate that same memory within the lifetime of the callee.
This is the result of the discussion on llvm-dev under the thread "Ambiguity in the nofree function attribute".
The most important part of this change is the LangRef wording. The rest is minor comment changes to emphasize the new semantics where code was accidentally consistent, and fix one place which wasn't consistent. That one place is currently narrowly used as it is primarily part of the ongoing (and not yet enabled) deref-at-point semantics work.
Differential Revision: https://reviews.llvm.org/D100141
Attributes don't know their parent Context, adding this would make Attribute larger. Instead, we add hasParentContext that answers whether this Attribute belongs to a particular LLVMContext by checking for itself inside the context's FoldingSet. Same with AttributeSet and AttributeList. The Verifier checks them with the Module context.
Differential Revision: https://reviews.llvm.org/D99362
When we pass a AArch64 Homogeneous Floating-Point
Aggregate (HFA) argument with increased alignment
requirements, for example
struct S {
__attribute__ ((__aligned__(16))) double v[4];
};
Clang uses `[4 x double]` for the parameter, which is passed
on the stack at alignment 8, whereas it should be at
alignment 16, following Rule C.4 in
AAPCS (https://github.com/ARM-software/abi-aa/blob/master/aapcs64/aapcs64.rst#642parameter-passing-rules)
Currently we don't have a way to express in LLVM IR the
alignment requirements of the function arguments. The align
attribute is applicable to pointers only, and only for some
special ways of passing arguments (e..g byval). When
implementing AAPCS32/AAPCS64, clang resorts to dubious hacks
of coercing to types, which naturally have the needed
alignment. We don't have enough types to cover all the
cases, though.
This patch introduces a new use of the stackalign attribute
to control stack slot alignment, when and if an argument is
passed in memory.
The attribute align is left as an optimizer hint - it still
applies to pointer types only and pertains to the content of
the pointer, whereas the alignment of the pointer itself is
determined by the stackalign attribute.
For byval arguments, the stackalign attribute assumes the
role, previously perfomed by align, falling back to align if
stackalign` is absent.
On the clang side, when passing arguments using the "direct"
style (cf. `ABIArgInfo::Kind`), now we can optionally
specify an alignment, which is emitted as the new
`stackalign` attribute.
Patch by Momchil Velikov and Lucas Prates.
Differential Revision: https://reviews.llvm.org/D98794
Value::replaceUsesOutsideBlock doesn't replace debug uses which leads to an
unnecessary reduction in variable location coverage. Fix this, add a unittest for
it, and add a regression test demonstrating the change through instcombine's
replacedSelectWithOperand.
Reviewed By: djtodoro
Differential Revision: https://reviews.llvm.org/D99169
"Does the predicate hold between two ranges?"
Not very surprisingly, some places were already doing this check,
without explicitly naming the algorithm, cleanup them all.
"Does the predicate hold between two ranges?"
Not very surprisingly, some places were already doing this check,
without explicitly naming the algorithm, cleanup them all.
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)
Follow up to a6d2a8d6f5. These were found by simply grepping for "::assume", and are the subset of that result which looked cleaner to me using the isa/dyn_cast patterns.
Problem:
On SystemZ we need to open text files in text mode. On Windows, files opened in text mode adds a CRLF '\r\n' which may not be desirable.
Solution:
This patch adds two new flags
- OF_CRLF which indicates that CRLF translation is used.
- OF_TextWithCRLF = OF_Text | OF_CRLF indicates that the file is text and uses CRLF translation.
Developers should now use either the OF_Text or OF_TextWithCRLF for text files and OF_None for binary files. If the developer doesn't want carriage returns on Windows, they should use OF_Text, if they do want carriage returns on Windows, they should use OF_TextWithCRLF.
So this is the behaviour per platform with my patch:
z/OS:
OF_None: open in binary mode
OF_Text : open in text mode
OF_TextWithCRLF: open in text mode
Windows:
OF_None: open file with no carriage return
OF_Text: open file with no carriage return
OF_TextWithCRLF: open file with carriage return
The Major change is in llvm/lib/Support/Windows/Path.inc to only set text mode if the OF_CRLF is set.
```
if (Flags & OF_CRLF)
CrtOpenFlags |= _O_TEXT;
```
These following files are the ones that still use OF_Text which I left unchanged. I modified all these except raw_ostream.cpp in recent patches so I know these were previously in Binary mode on Windows.
./llvm/lib/Support/raw_ostream.cpp
./llvm/lib/TableGen/Main.cpp
./llvm/tools/dsymutil/DwarfLinkerForBinary.cpp
./llvm/unittests/Support/Path.cpp
./clang/lib/StaticAnalyzer/Core/HTMLDiagnostics.cpp
./clang/lib/Frontend/CompilerInstance.cpp
./clang/lib/Driver/Driver.cpp
./clang/lib/Driver/ToolChains/Clang.cpp
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D99426
This patch enhances hasAddressTaken() to ignore bitcasts as a
callee in callbase instruction. Such bitcast usage doesn't really take
the address in a useful meaningful way.
Reviewed By: rampitec
Differential Revision: https://reviews.llvm.org/D98884
When we are able to SROA an alloca, we know all uses of it, meaning we
don't have to preserve the invariant group intrinsics and metadata.
It's possible that we could lose information regarding redundant
loads/stores, but that's unlikely to have any real impact since right
now the only user is Clang and vtables.
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D99760
We have this logic duplicated in several cases, none of which were exhaustive. Consolidate it in one place.
I don't believe this actually impacts behavior of the callers. I think they all filter their inputs such that their partial implementations were correct. If not, this might be fixing a cornercase bug.
Support deriving dereferenceability facts from allocation sites with known object sizes while correctly accounting for any possibly frees between allocation and use site. (At the moment, we're conservative and only allowing it in functions where we know we can't free.)
This is part of the work on deref-at-point semantics. I'm making the change unconditional as the miscompile in this case is way too easy to trip by accident, and the optimization was only recently added (by me).
There will be a follow up patch wiring through TLI since that should now be doable without introducing widespread miscompiles.
Differential Revision: https://reviews.llvm.org/D95815
MemberOffsets are stored at the end of StructLayout. The class
contains a single entry array to mark the start of the member
offsets. getStructLayout calculates the additional space needed
for additional elements before allocating memory.
This patch converts this to use TrailingObjects. This simplifies
the size computation in getStructLayout and gets rid of the
single entry array.
This is prep work, but to use TypeSize instead of uint64_t for
D98169. The single entry array doesn't work with TypeSize because
TypeSize doesn't have a default constructor. We thought this
change was an improvement by itself so we've separated it out.
Reviewed By: mehdi_amini
Differential Revision: https://reviews.llvm.org/D99608
Negative numbers are represented using DW_OP_consts along with signed representation
of the number as the argument.
Test case IR is generated using Fortran front-end.
Reviewed By: aprantl
Differential Revision: https://reviews.llvm.org/D99273
Currently prof metadata with branch counts is added only for BranchInst and SwitchInst, but not for IndirectBrInst. As a result, BPI/BFI make incorrect inferences for indirect branches, which can be very hot.
This diff adds metadata for IndirectBrInst, in addition to BranchInst and SwitchInst.
Reviewed By: wmi, wenlei
Differential Revision: https://reviews.llvm.org/D99550
This is needed for Fortran assumed shape arrays whose dimensions are
defined as,
- 'count' is taken from array descriptor passed as parameter by
caller, access from descriptor is defined by type DIExpression.
- 'lowerBound' is defined by callee.
The current alternate way represents using upperBound in place of
count, where upperBound is calculated in callee in a temp variable
using lowerBound and count
Representation with count (DIExpression) is not only clearer as
compared to upperBound (DIVariable) but it has another advantage that
variable count is accessed by being parameter has better chance of
survival at higher optimization level than upperBound being local
variable.
Reviewed By: aprantl
Differential Revision: https://reviews.llvm.org/D99335
This commit adds debugging support for set types defined in languages
such as Pascal and Modula-2.
Patch by Peter McKinna!
Differential Revision: https://reviews.llvm.org/D76115
during profile update.
When we inline a function and update the profile, the value profiles of the
indirect call in the inliner and inlinee will be scaled. In
https://reviews.llvm.org/D96806 and https://reviews.llvm.org/D97350, we start
using the magic number NOMORE_ICP_MAGICNUM (-1) to mark targets which have
been promoted. The magic number shouldn't be scaled during the profile update.
Although the problem has been suppressed by https://reviews.llvm.org/D98187
for SampleFDO, which stops profile update for inlining in sampleFDO, the patch
is still wanted since it will be more consistent to handle the magic number
properly in profile update.
Differential Revision: https://reviews.llvm.org/D99394
I think byval/sret and the others are close to being able to rip out
the code to support the missing type case. A lot of this code is
shared with inalloca, so catch this up to the others so that can
happen.
In DeadArgumentElimination pass, if a function's argument is never used, corresponding caller's parameter can be changed to undef. If the param/arg has attribute noundef or other related attributes, LLVM LangRef(https://llvm.org/docs/LangRef.html#parameter-attributes) says its behavior is undefined. SimplifyCFG(D97244) takes advantage of this behavior and does bad transformation on valid code.
To avoid this undefined behavior when change caller's parameter to undef, this patch removes noundef attribute and other attributes imply noundef on param/arg.
Differential Revision: https://reviews.llvm.org/D98899
All of these are scoped allocations which remain dereferenceable during the lifetime of the callee.
Differential Revision: https://reviews.llvm.org/D99310
Rather than special-casing assume in BasicAA getModRefBehavior(),
do this one level higher, in the attribute handling of CallBase.
For assumes with operand bundles, the inaccessiblememonly attribute
applies regardless of operand bundles.
This implements a subset of the initial set of inference rules proposed in the llvm-dev thread "RFC: Decomposing deref(N) into deref(N) + nofree". The nolias one got moved to a separate review as there was some concerns raised which require further discussion.
Differential Revision: https://reviews.llvm.org/D99135
This patch adds a new llvm.experimental.stepvector intrinsic,
which takes no arguments and returns a linear integer sequence of
values of the form <0, 1, ...>. It is primarily intended for
scalable vectors, although it will work for fixed width vectors
too. It is intended that later patches will make use of this
new intrinsic when vectorising induction variables, currently only
supported for fixed width. I've added a new CreateStepVector
method to the IRBuilder, which will generate a call to this
intrinsic for scalable vectors and fall back on creating a
ConstantVector for fixed width.
For scalable vectors this intrinsic is lowered to a new ISD node
called STEP_VECTOR, which takes a single constant integer argument
as the step. During lowering this argument is set to a value of 1.
The reason for this additional argument at the codegen level is
because in future patches we will introduce various generic DAG
combines such as
mul step_vector(1), 2 -> step_vector(2)
add step_vector(1), step_vector(1) -> step_vector(2)
shl step_vector(1), 1 -> step_vector(2)
etc.
that encourage a canonical format for all targets. This hopefully
means all other targets supporting scalable vectors can benefit
from this too.
I've added cost model tests for both fixed width and scalable
vectors:
llvm/test/Analysis/CostModel/AArch64/neon-stepvector.ll
llvm/test/Analysis/CostModel/AArch64/sve-stepvector.ll
as well as codegen lowering tests for fixed width and scalable
vectors:
llvm/test/CodeGen/AArch64/neon-stepvector.ll
llvm/test/CodeGen/AArch64/sve-stepvector.ll
See this thread for discussion of the intrinsic:
https://lists.llvm.org/pipermail/llvm-dev/2021-January/147943.html
This attribute represents the minimum and maximum values vscale can
take. For now this attribute is not hooked up to anything during
codegen, this will be added in the future when such codegen is
considered stable.
Additionally hook up the -msve-vector-bits=<x> clang option to emit this
attribute.
Differential Revision: https://reviews.llvm.org/D98030
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.
This patch is plumbing to support work towards the goal outlined in the recent llvm-dev post "[llvm-dev] RFC: Decomposing deref(N) into deref(N) + nofree".
The point of this change is purely to simplify iteration on other pieces on way to making the switch. Rebuilding with a change to Value.h is slow and painful, so I want to get the API change landed. Once that's done, I plan to more closely audit each caller, add the inference rules in their own patch, then post a patch with the langref changes and test diffs. The value of the command line flag is that we can exercise the inference logic in standalone patches without needing the whole switch ready to go just yet.
Differential Revision: https://reviews.llvm.org/D98908
This patch adds support for intrinsic overloading on unnamed types.
This fixes PR38117 and PR48340 and will also be needed for the Full Restrict Patches (D68484).
The main problem is that the intrinsic overloading name mangling is using 's_s' for unnamed types.
This can result in identical intrinsic mangled names for different function prototypes.
This patch changes this by adding a '.XXXXX' to the intrinsic mangled name when at least one of the types is based on an unnamed type, ensuring that we get a unique name.
Implementation details:
- The mapping is created on demand and kept in Module.
- It also checks for existing clashes and recycles potentially existing prototypes and declarations.
- Because of extra data in Module, Intrinsic::getName needs an extra Module* argument and, for speed, an optional FunctionType* argument.
- I still kept the original two-argument 'Intrinsic::getName' around which keeps the original behavior (providing the base name).
-- Main reason is that I did not want to change the LLVMIntrinsicGetName version, as I don't know how acceptable such a change is
-- The current situation already has a limitation. So that should not get worse with this patch.
- Intrinsic::getDeclaration and the verifier are now using the new version.
Other notes:
- As far as I see, this should not suffer from stability issues. The count is only added for prototypes depending on at least one anonymous struct
- The initial count starts from 0 for each intrinsic mangled name.
- In case of name clashes, existing prototypes are remembered and reused when that makes sense.
Reviewed By: fhahn
Differential Revision: https://reviews.llvm.org/D91250
Fixed section of code that iterated through a SmallDenseMap and added
instructions in each iteration, causing non-deterministic code; replaced
SmallDenseMap with MapVector to prevent non-determinism.
This reverts commit 01ac6d1587.
This caused non-deterministic compiler output; see comment on the
code review.
> This patch updates the various IR passes to correctly handle dbg.values with a
> DIArgList location. This patch does not actually allow DIArgLists to be produced
> by salvageDebugInfo, and it does not affect any pass after codegen-prepare.
> Other than that, it should cover every IR pass.
>
> Most of the changes simply extend code that operated on a single debug value to
> operate on the list of debug values in the style of any_of, all_of, for_each,
> etc. Instances of setOperand(0, ...) have been replaced with with
> replaceVariableLocationOp, which takes the value that is being replaced as an
> additional argument. In places where this value isn't readily available, we have
> to track the old value through to the point where it gets replaced.
>
> Differential Revision: https://reviews.llvm.org/D88232
This reverts commit df69c69427.
Previously NEON used a target specific intrinsic for frintn, given that
the FROUNDEVEN ISD node now exists, move over to that instead and add
codegen support for that node for both NEON and fixed length SVE.
Differential Revision: https://reviews.llvm.org/D98487
This avoids a few unnecessary conversion from StringRef to std::string, and a
bunch of extra allocation thanks to the SmallString.
Differential Revision: https://reviews.llvm.org/D98190
This patch adds support for reverse loop vectorization.
It is possible to vectorize the following loop:
```
for (int i = n-1; i >= 0; --i)
a[i] = b[i] + 1.0;
```
with fixed or scalable vector.
The loop-vectorizer will use 'reverse' on the loads/stores to make
sure the lanes themselves are also handled in the right order.
This patch adds support for scalable vector on IRBuilder interface to
create a reverse vector. The IR function
CreateVectorReverse lowers to experimental.vector.reverse for scalable vector
and keedp the original behavior for fixed vector using shuffle reverse.
Differential Revision: https://reviews.llvm.org/D95363
The load/store instruction will be transformed to amx intrinsics
in the pass of AMX type lowering. Prohibiting the pointer cast
make that pass happy.
Differential Revision: https://reviews.llvm.org/D98247
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
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
The LiveDebugValues and LiveDebugVariables implementations for handling
DBG_VALUE_LIST instructions can be simplified significantly if they do not have
to deal with any duplicated operands, such as a DBG_VALUE_LIST that uses the
same register multiple times in its expression. This patch adds a function,
replaceArg, that can be used to simplify a DIExpression in the case of
duplicated operands.
Differential Revision: https://reviews.llvm.org/D83896
This patch updates the various IR passes to correctly handle dbg.values with a
DIArgList location. This patch does not actually allow DIArgLists to be produced
by salvageDebugInfo, and it does not affect any pass after codegen-prepare.
Other than that, it should cover every IR pass.
Most of the changes simply extend code that operated on a single debug value to
operate on the list of debug values in the style of any_of, all_of, for_each,
etc. Instances of setOperand(0, ...) have been replaced with with
replaceVariableLocationOp, which takes the value that is being replaced as an
additional argument. In places where this value isn't readily available, we have
to track the old value through to the point where it gets replaced.
Differential Revision: https://reviews.llvm.org/D88232
The code used for propagating equalities (e.g. assume facts) was conservative in two ways - one of which this patch fixes. Specifically, it shifts the code reasoning about whether a use is dominated by the end of the assume block to consider phi uses to exist on the predecessor edge. This matches the dominator tree handling for dominates(Edge, Use), and simply extends it to dominates(BB, Use).
Note that the decision to use the end of the block is itself a conservative choice. The more precise option would be to use the later of the assume and the value, and replace all uses after that. GVN handles that case separately (with the replace operand mechanism) because it used to be expensive to ask dominator questions within blocks. With the new instruction ordering support, we should probably rewrite this code at some point to simplify.
Differential Revision: https://reviews.llvm.org/D98082
Return UGT rather than NE for icmp @g, null, which is slightly
stronger. This is consistent with what we do for more complex
folds. It is somewhat silly that @g ugt null does not get folded
while (gep @g) ugt null does.
While @g ugt null is always true (ignoring weak symbols),
@g sgt null is not necessarily the case -- that would imply that
it is forbidden to place globals in the high half of the address
space.
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.
I noticed that we were not folding expressions like this:
icmp ult (constexpr), null
in https://llvm.org/PR49355, so we end up with extremely large
icmp instructions as the constant expressions pile up on each other.
There is no potential to mis-fold an unsigned boundary condition
with a zero/null, so this is just falling through a crack in the
pattern matching.
The more general case of comparisons of non-zero constants and
constexpr are more tricky and may require the datalayout to know
how to cast to different types, etc. Negative tests verify that
we are only changing a subset of potential patterns.
Differential Revision: https://reviews.llvm.org/D98150
This patch adds a new metadata node, DIArgList, which contains a list of SSA
values. This node is in many ways similar in function to the existing
ValueAsMetadata node, with the difference being that it tracks a list instead of
a single value. Internally, it uses ValueAsMetadata to track the individual
values, but there is also a reasonable amount of DIArgList-specific
value-tracking logic on top of that. Similar to ValueAsMetadata, it is a special
case in parsing and printing due to the fact that it requires a function state
(as it may reference function-local values).
This patch should not result in any immediate functional change; it allows for
DIArgLists to be parsed and printed, but debug variable intrinsics do not yet
recognize them as a valid argument (outside of parsing).
Differential Revision: https://reviews.llvm.org/D88175
Rewrites test to use correct architecture triple; fixes incorrect
reference in SourceLevelDebugging doc; simplifies `spillReg` behaviour
so as to not be dependent on changes elsewhere in the patch stack.
This reverts commit d2000b45d0.
This is included from IR files, and IR doesn't/can't depend on Analysis
(because Analysis depends on IR).
Also fix the implementation - don't use non-member static in headers, as
it leads to ODR violations, inaccurate "unused function" warnings, etc.
And fix the header protection macro name (we don't generally include
"LIB" in the names, so far as I can tell).
explicitly emitting retainRV or claimRV calls in the IR
This reapplies ed4718eccb, which was reverted
because it was causing a miscompile. The bug that was causing the miscompile
has been fixed in 75805dce5f.
Original commit message:
Background:
This fixes a longstanding problem where llvm breaks ARC's autorelease
optimization (see the link below) by separating calls from the marker
instructions or retainRV/claimRV calls. The backend changes are in
https://reviews.llvm.org/D92569.
https://clang.llvm.org/docs/AutomaticReferenceCounting.html#arc-runtime-objc-autoreleasereturnvalue
What this patch does to fix the problem:
- The front-end adds operand bundle "clang.arc.attachedcall" to calls,
which indicates the call is implicitly followed by a marker
instruction and an implicit retainRV/claimRV call that consumes the
call result. In addition, it emits a call to
@llvm.objc.clang.arc.noop.use, which consumes the call result, to
prevent the middle-end passes from changing the return type of the
called function. This is currently done only when the target is arm64
and the optimization level is higher than -O0.
- ARC optimizer temporarily emits retainRV/claimRV calls after the calls
with the operand bundle in the IR and removes the inserted calls after
processing the function.
- ARC contract pass emits retainRV/claimRV calls after the call with the
operand bundle. It doesn't remove the operand bundle on the call since
the backend needs it to emit the marker instruction. The retainRV and
claimRV calls are emitted late in the pipeline to prevent optimization
passes from transforming the IR in a way that makes it harder for the
ARC middle-end passes to figure out the def-use relationship between
the call and the retainRV/claimRV calls (which is the cause of
PR31925).
- The function inliner removes an autoreleaseRV call in the callee if
nothing in the callee prevents it from being paired up with the
retainRV/claimRV call in the caller. It then inserts a release call if
claimRV is attached to the call since autoreleaseRV+claimRV is
equivalent to a release. If it cannot find an autoreleaseRV call, it
tries to transfer the operand bundle to a function call in the callee.
This is important since the ARC optimizer can remove the autoreleaseRV
returning the callee result, which makes it impossible to pair it up
with the retainRV/claimRV call in the caller. If that fails, it simply
emits a retain call in the IR if retainRV is attached to the call and
does nothing if claimRV is attached to it.
- SCCP refrains from replacing the return value of a call with a
constant value if the call has the operand bundle. This ensures the
call always has at least one user (the call to
@llvm.objc.clang.arc.noop.use).
- This patch also fixes a bug in replaceUsesOfNonProtoConstant where
multiple operand bundles of the same kind were being added to a call.
Future work:
- Use the operand bundle on x86-64.
- Fix the auto upgrader to convert call+retainRV/claimRV pairs into
calls with the operand bundles.
rdar://71443534
Differential Revision: https://reviews.llvm.org/D92808
This patch adds a new instruction that can represent variadic debug values,
DBG_VALUE_VAR. This patch alone covers the addition of the instruction and a set
of basic code changes in MachineInstr and a few adjacent areas, but does not
correctly handle variadic debug values outside of these areas, nor does it
generate them at any point.
The new instruction is similar to the existing DBG_VALUE instruction, with the
following differences: the operands are in a different order, any number of
values may be used in the instruction following the Variable and Expression
operands (these are referred to in code as “debug operands”) and are indexed
from 0 so that getDebugOperand(X) == getOperand(X+2), and the Expression in a
DBG_VALUE_VAR must use the DW_OP_LLVM_arg operator to pass arguments into the
expression.
The new DW_OP_LLVM_arg operator is only valid in expressions appearing in a
DBG_VALUE_VAR; it takes a single argument and pushes the debug operand at the
index given by the argument onto the Expression stack. For example the
sub-expression `DW_OP_LLVM_arg, 0` has the meaning “Push the debug operand at
index 0 onto the expression stack.”
Differential Revision: https://reviews.llvm.org/D82363
Same dangling probes are redundant since they all have the same semantic that is to rely on the counts inference tool to get reasonable count for the same original block. Therefore, there's no need to keep multiple copies of them. I've seen jump threading created tons of redundant dangling probes that slowed down the compiler dramatically. Other optimization passes can also result in redundant probes though without an observed impact so far.
This change removes block-wise redundant dangling probes specifically introduced by jump threading. To support removing redundant dangling probes caused by all other passes, a final function-wise deduplication is also added.
An 18% size win of the .pseudo_probe section was seen for SPEC2017. No performance difference was observed.
Differential Revision: https://reviews.llvm.org/D97482
This change fixes a couple places where the pseudo probe intrinsic blocks optimizations because they are not naturally removable. To unblock those optimizations, the blocking pseudo probes are moved out of the original blocks and tagged dangling, instead of allowing pseudo probes to be literally removed. The reason is that when the original block is removed, we won't be able to sample it. Instead of assigning it a zero weight, moving all its pseudo probes into another block and marking them dangling should allow the counts inference a chance to assign them a more reasonable weight. We have not seen counts quality degradation from our experiments.
The optimizations being unblocked are:
1. Removing conditional probes for if-converted branches. Conditional probes are tagged dangling when their homing branch arms are folded so that they will not be over-counted.
2. Unblocking jump threading from removing empty blocks. Pseudo probe prevents jump threading from removing logically empty blocks that only has one unconditional jump instructions.
3. Unblocking SimplifyCFG and MIR tail duplicate to thread empty blocks and blocks with redundant branch checks.
Since dangling probes are logically deleted, they should not consume any samples in LTO postLink. This can be achieved by setting their distribution factors to zero when dangled.
Reviewed By: wmi
Differential Revision: https://reviews.llvm.org/D97481
This caused miscompiles of Chromium tests for iOS due clobbering of live
registers. See discussion on the code review for details.
> Background:
>
> This fixes a longstanding problem where llvm breaks ARC's autorelease
> optimization (see the link below) by separating calls from the marker
> instructions or retainRV/claimRV calls. The backend changes are in
> https://reviews.llvm.org/D92569.
>
> https://clang.llvm.org/docs/AutomaticReferenceCounting.html#arc-runtime-objc-autoreleasereturnvalue
>
> What this patch does to fix the problem:
>
> - The front-end adds operand bundle "clang.arc.attachedcall" to calls,
> which indicates the call is implicitly followed by a marker
> instruction and an implicit retainRV/claimRV call that consumes the
> call result. In addition, it emits a call to
> @llvm.objc.clang.arc.noop.use, which consumes the call result, to
> prevent the middle-end passes from changing the return type of the
> called function. This is currently done only when the target is arm64
> and the optimization level is higher than -O0.
>
> - ARC optimizer temporarily emits retainRV/claimRV calls after the calls
> with the operand bundle in the IR and removes the inserted calls after
> processing the function.
>
> - ARC contract pass emits retainRV/claimRV calls after the call with the
> operand bundle. It doesn't remove the operand bundle on the call since
> the backend needs it to emit the marker instruction. The retainRV and
> claimRV calls are emitted late in the pipeline to prevent optimization
> passes from transforming the IR in a way that makes it harder for the
> ARC middle-end passes to figure out the def-use relationship between
> the call and the retainRV/claimRV calls (which is the cause of
> PR31925).
>
> - The function inliner removes an autoreleaseRV call in the callee if
> nothing in the callee prevents it from being paired up with the
> retainRV/claimRV call in the caller. It then inserts a release call if
> claimRV is attached to the call since autoreleaseRV+claimRV is
> equivalent to a release. If it cannot find an autoreleaseRV call, it
> tries to transfer the operand bundle to a function call in the callee.
> This is important since the ARC optimizer can remove the autoreleaseRV
> returning the callee result, which makes it impossible to pair it up
> with the retainRV/claimRV call in the caller. If that fails, it simply
> emits a retain call in the IR if retainRV is attached to the call and
> does nothing if claimRV is attached to it.
>
> - SCCP refrains from replacing the return value of a call with a
> constant value if the call has the operand bundle. This ensures the
> call always has at least one user (the call to
> @llvm.objc.clang.arc.noop.use).
>
> - This patch also fixes a bug in replaceUsesOfNonProtoConstant where
> multiple operand bundles of the same kind were being added to a call.
>
> Future work:
>
> - Use the operand bundle on x86-64.
>
> - Fix the auto upgrader to convert call+retainRV/claimRV pairs into
> calls with the operand bundles.
>
> rdar://71443534
>
> Differential Revision: https://reviews.llvm.org/D92808
This reverts commit ed4718eccb.