David L. Jones [Thu, 4 Apr 2019 02:27:57 +0000 (02:27 +0000)]
Revert r357452 - 'SimplifyCFG SinkCommonCodeFromPredecessors: Also sink function calls without used results (PR41259)'
This revision causes tests to fail under ASAN. Since the cause of the failures
is not clear (could be ASAN, could be a Clang bug, could be a bug in this
revision), the safest course of action seems to be to revert while investigating.
Revert "[analyzer] Toning down invalidation a bit".
This reverts commit r352473.
The overall idea is great, but it seems to cause unintented consequences
when not only Region Store invalidation but also pointer escape mechanism
was accidentally affected.
Based on discussions in https://reviews.llvm.org/D58121#1452483
and https://reviews.llvm.org/D57230#1434161
[clang-format] Do not emit replacements while regrouping if Cpp includes are OK
Summary:
Currently clang-format would always emit a replacement for multi-block #include
sections if `IBS_Regroup`, even if the sections are correct:
```
% cat ~/test.h
#include <a.h>
Add a new attribute documentation category for declarations.
This moves documentation for some attributes into new categories that are hopefully a bit more clear. In general, "Type" documentation should be for attributes that appertain to types while "Declaration" documentation should be for attributes that appertain to declarations other than functions or variables.
[LibTooling] Add Transformer, a library for source-to-source transformations.
Summary: Adds a basic version of Transformer, a library supporting the concise specification of clang-based source-to-source transformations. A full discussion of the end goal can be found on the cfe-dev list with subject "[RFC] Easier source-to-source transformations with clang tooling".
Eric Liu [Wed, 3 Apr 2019 09:25:16 +0000 (09:25 +0000)]
[clang-format] Regroup #includes into blocks for Google style
Summary:
Regrouping #includes in blocks separated by blank lines when sorting C++ #include
headers was implemented recently, and it has been preferred in Google's C++ style guide:
https://google.github.io/styleguide/cppguide.html#Names_and_Order_of_Includes
Summary:
This commit adds a chapter 'CLion integration' to ClangFormat.rst.
The official announcement of clang-format support in CLion 2019.1: https://blog.jetbrains.com/clion/2019/03/clion-2019-1-embedded-dev-clangformat-memory-view/
check-all invokes check-clang-python which prints the annoying message:
LIBCLANG TOOLING ERROR: fixed-compilation-database: Error while opening fixed database: No such file or directory
json-compilation-database: Error while opening JSON database: No such file or directory
[analyzer] When failing to evaluate a __builtin_constant_p, presume it's false.
__builtin_constant_p(x) is a compiler builtin that evaluates to 1 when
its argument x is a compile-time constant and to 0 otherwise. In CodeGen
it is simply lowered to the respective LLVM intrinsic. In the Analyzer
we've been trying to delegate modeling to Expr::EvaluateAsInt, which is
allowed to sometimes fail for no apparent reason.
When it fails, let's conservatively return false. Modeling it as false
is pretty much never wrong, and it is only required to return true
on a best-effort basis, which every user should expect.
Fixes VLAChecker false positives on code that tries to emulate
static asserts in C by constructing a VLA of dynamic size -1 under the
assumption that this dynamic size is actually a constant
in the sense of __builtin_constant_p.
[WebAssembly] Add Emscripten OS definition + small_printf
The Emscripten OS provides a definition of __EMSCRIPTEN__, and also that it
supports iprintf optimizations.
Also define small_printf optimizations, which is a printf with float support
but not long double (which in wasm can be useful since long doubles are 128
bit and force linking of float128 emulation code). This part is based on
sunfish's https://reviews.llvm.org/D57620 (which can't land yet since
the WASI integration isn't ready yet).
Erik Pilkington [Tue, 2 Apr 2019 19:48:11 +0000 (19:48 +0000)]
[Sema] Fix a use-after-deallocate of a ParsedAttr
moveAttrFromListToList only makes sense when moving an attribute to a list with
a pool that's either equivalent, or has a shorter lifetime. Therefore, using it
to move a ParsedAttr from a declarator to a declaration specifier doesn't make
sense, since the declaration specifier's pool outlives the declarator's. The
patch adds a new function, ParsedAttributes::takeOneFrom, which transfers the
attribute from one pool to another, fixing the use-after-deallocate.
Simon Atanasyan [Tue, 2 Apr 2019 18:03:31 +0000 (18:03 +0000)]
[driver][mips] Check both `gnuabi64` and `gnu` suffixes in `getMultiarchTriple`
In case of N64 ABI toolchain paths migth have `mips-linux-gnuabi64`
or `mips-linux-gnu` directory regardless of selected environment.
Check both variants while detecting a multiarch triple.
Fix for the bug https://bugs.llvm.org/show_bug.cgi?id=41204
Allow the optimizer to remove unnecessary EH cleanups surrounding calls
to os_log_helper, to save some code size.
As a follow-up, it might be worthwhile to add a BasicNoexcept exception
spec to os_log_helper, and to then teach CGCall to emit direct calls for
callees which can't throw. This could save some compile-time.
Hans Wennborg [Tue, 2 Apr 2019 08:01:38 +0000 (08:01 +0000)]
SimplifyCFG SinkCommonCodeFromPredecessors: Also sink function calls without used results (PR41259)
The code was previously checking that candidates for sinking had exactly
one use or were a store instruction (which can't have uses). This meant
we could sink call instructions only if they had a use.
That limitation seemed a bit arbitrary, so this patch changes it to
"instruction has zero or one use" which seems more natural and removes
the need to special-case stores.
Michael Kruse [Mon, 1 Apr 2019 17:47:41 +0000 (17:47 +0000)]
[CodeGen] Generate follow-up metadata for loops with more than one transformation.
Before this patch, CGLoop would dump all transformations for a loop into
a single LoopID without encoding any order in which to apply them.
rL348944 added the possibility to encode a transformation order using
followup-attributes.
When a loop has more than one transformation, use the follow-up
attribute define the order in which they are applied. The emitted order
is the defacto order as defined by the current LLVM pass pipeline,
which is:
This patch should therefore not change the assembly output, assuming
that all explicit transformations can be applied, and no implicit
transformations in-between. In the former case,
WarnMissedTransformationsPass should emit a warning (except for
MachinePipeliner which is not implemented yet). The latter could be
avoided by adding 'llvm.loop.disable_nonforced' attributes.
Because LoopUnrollAndJamPass processes a loop nest, generation of the
MDNode is delayed to after the inner loop metadata have been processed.
A temporary LoopID is therefore used to annotate instructions and
RAUW'ed by the actual LoopID later.
[OPENMP]Allocate clause allocator in target region.
According to OpenMP 5.0, 2.11.4 allocate Clause, Restrictions, allocate
clauses that appear on a target construct or on constructs in a target
region must specify an allocator expression unless a requires directive
with the dynamic_allocators clause is present in the same compilation
unit. Patch adds a check for this restriction.
Summary:
ASTStructuralEquivalence uses a flag to indicate whether ODR diagnostics
should be considered errors or warnings as module Sema is more strict than
ASTMerge. The implementation of ASTImporter should allso follow
along the same lines.
[ASTImporter] Make ODR error handling configurable
Summary:
ODR errors are not necessarily true errors during the import of ASTs.
ASTMerge and CrossTU should use the warning equivalent of every CTU error,
while Sema should emit errors as before.
[OPENMP] Check that allocated variables are used in private clauses.
According to OpenMP 5.0 standard, 2.11.4 allocate Clause, Restrictions,
For any list item that is specified in the allocate clause on a
directive, a data-sharing attribute clause that may create a private
copy of that list item must be specified on the same directive. Patch
adds the checks for this restriction.
Sanjay Patel [Sun, 31 Mar 2019 15:01:30 +0000 (15:01 +0000)]
[InstCombine] canonicalize select shuffles by commuting
In PR41304:
https://bugs.llvm.org/show_bug.cgi?id=41304
...we have a case where we want to fold a binop of select-shuffle (blended) values.
Rather than try to match commuted variants of the pattern, we can canonicalize the
shuffles and check for mask equality with commuted operands.
We don't produce arbitrary shuffle masks in instcombine, but select-shuffles are a
special case that the backend is required to handle because we already canonicalize
vector select to this shuffle form.
So there should be no codegen difference from this change. It's possible that this
improves CSE in IR though.
David Chisnall [Sun, 31 Mar 2019 11:22:33 +0000 (11:22 +0000)]
[gnustep-objc] Make the GNUstep v2 ABI work for Windows DLLs.
Summary:
Based on a patch by Dustin Howett, modified to not change the ABI for
ELF platforms.
Use more Windows-like section names.
This also makes things more readable by PE/COFF debug tools that assume
sections fit in the first header.
With these changes in, it is now possible to build a working WinObjC
with clang and the WinObjC version of GNUstep libobjc (upstream GNUstep
libobjc + a work around for incremental linking, which can be removed
once LINK.EXE gains a feature to opt sections out of receiving extra
padding during an incremental link).
This patch aims to add support for the following rules from the JUCE coding standards:
- Always put a space before an open parenthesis that contains text - e.g. foo (123);
- Never put a space before an empty pair of open/close parenthesis - e.g. foo();
Anton Afanasyev [Sat, 30 Mar 2019 08:42:48 +0000 (08:42 +0000)]
Adds `-ftime-trace` option to clang that produces Chrome `chrome://tracing` compatible JSON profiling output dumps.
This change adds hierarchical "time trace" profiling blocks that can be visualized in Chrome, in a "flame chart" style. Each profiling block can have a "detail" string that for example indicates the file being processed, template name being instantiated, function being optimized etc.
This is taken from GitHub PR: https://github.com/aras-p/llvm-project-20170507/pull/2
Hubert Tong [Fri, 29 Mar 2019 23:33:04 +0000 (23:33 +0000)]
[lit] Set shlibpath_var on AIX
Summary:
When building the `check-all` target on AIX, lit produces
```
warning: unable to inject shared library path on 'AIX'
```
This patch addresses this. `LIBPATH` is the environment variable of
interest on AIX. Newer versions of AIX may consider `LD_LIBRARY_PATH`,
but only when `LIBPATH` is unset.
Artem Dergachev [Fri, 29 Mar 2019 22:57:49 +0000 (22:57 +0000)]
[analyzer] PR41239: Fix a crash on invalid source location in NoStoreFuncVisitor.
It turns out that SourceManager::isInSystemHeader() crashes when an invalid
source location is passed into it. Invalid source locations are relatively
common: not only they come from body farms, but also, say, any function in C
that didn't come with a forward declaration would have an implicit
forward declaration with invalid source locations.
There's a more comfy API for us to use in the Static Analyzer:
CallEvent::isInSystemHeader(), so just use that.
Artem Dergachev [Fri, 29 Mar 2019 22:49:30 +0000 (22:49 +0000)]
[analyzer] Move taint API from ProgramState to a separate header. NFC.
It is now an inter-checker communication API, similar to the one that
connects MallocChecker/CStringChecker/InnerPointerChecker: simply a set of
setters and getters for a state trait.
Artem Dergachev [Fri, 29 Mar 2019 22:43:34 +0000 (22:43 +0000)]
[analyzer] PR37501: Disable assertion for logical op short circuit evaluation.
The transfer function for the CFG element that represents a logical operation
computes the value of the operation and does nothing else. The element
appears after all the short circuit decisions were made, so they don't need
to be made again at this point.
Because our expression evaluation is imprecise, it is often hard to
discriminate between:
(1) we don't know the value of the RHS because we failed to evaluate it
and
(2) we don't know the value of the RHS because it didn't need to be evaluated.
This is hard because it depends on our knowledge about the value of the LHS
(eg., if LHS is true, then RHS in (LHS || RHS) doesn't need to be computed)
but LHS itself may have been evaluated imprecisely and we don't know whether
it is true or not. Additionally, the Analyzer wouldn't necessarily even remember
what the value of the LHS was because theoretically it's not really necessary
to know it for any future evaluations.
In order to work around these issues, the transfer function for logical
operations consists in looking at the ExplodedGraph we've constructed so far
in order to figure out from which CFG direction did we arrive here.
Such post-factum backtracking that doesn't involve looking up LHS and RHS values
is usually possible. However sometimes it fails because when we deduplicate
exploded nodes with the same program point and the same program state we may end
up in a situation when we reached the same program point from two or more
different directions.
By removing the assertion, we admit that the procedure indeed sometimes fails to
work. When it fails, we also admit that we don't know the value of the logical
operator.
Artem Dergachev [Fri, 29 Mar 2019 22:21:00 +0000 (22:21 +0000)]
[analyzer] Introduce a simplified API for adding custom path notes.
Almost all path-sensitive checkers need to tell the user when something specific
to that checker happens along the execution path but does not constitute a bug
on its own. For instance, a call to operator delete in C++ has consequences
that are specific to a use-after-free bug. Deleting an object is not a bug
on its own, but when the Analyzer finds an execution path on which a deleted
object is used, it'll have to explain to the user when exactly during that path
did the deallocation take place.
Historically such custom notes were added by implementing "bug report visitors".
These visitors were post-processing bug reports by visiting every ExplodedNode
along the path and emitting path notes whenever they noticed that a change that
is relevant to a bug report occurs within the program state. For example,
it emits a "memory is deallocated" note when it notices that a pointer changes
its state from "allocated" to "deleted".
The "visitor" approach is powerful and efficient but hard to use because
such preprocessing implies that the developer first models the effects
of the event (say, changes the pointer's state from "allocated" to "deleted"
as part of operator delete()'s transfer function) and then forgets what happened
and later tries to reverse-engineer itself and figure out what did it do
by looking at the report.
The proposed approach tries to avoid discarding the information that was
available when the transfer function was evaluated. Instead, it allows the
developer to capture all the necessary information into a closure that
will be automatically invoked later in order to produce the actual note.
This should reduce boilerplate and avoid very painful logic duplication.
On the technical side, the closure is a lambda that's put into a special kind of
a program point tag, and a special bug report visitor visits all nodes in the
report and invokes all note-producing closures it finds along the path.
For now it is up to the lambda to make sure that the note is actually relevant
to the report. For instance, a memory deallocation note would be irrelevant when
we're reporting a division by zero bug or if we're reporting a use-after-free
of a different, unrelated chunk of memory. The lambda can figure these thing out
by looking at the bug report object that's passed into it.
A single checker is refactored to make use of the new functionality: MIGChecker.
Its program state is trivial, making it an easy testing ground for the first
version of the API.
Thomas Lively [Fri, 29 Mar 2019 22:00:18 +0000 (22:00 +0000)]
[WebAssembly] Add mutable globals feature
Summary:
This feature is not actually used for anything in the WebAssembly
backend, but adding it allows users to get it into the target features
sections of their objects, which makes these objects
future-compatible.
Volodymyr Sapsai [Fri, 29 Mar 2019 18:47:07 +0000 (18:47 +0000)]
[Sema] Fix assertion when `auto` parameter in lambda has an attribute.
Fixes the assertion
> no Attr* for AttributedType*
> UNREACHABLE executed at llvm-project/clang/lib/Sema/SemaType.cpp:298!
In `TypeProcessingState::getAttributedType` we put into `AttrsForTypes`
types with `auto` but later in
`TypeProcessingState::takeAttrForAttributedType` we use transformed
types and that's why cannot find `Attr` corresponding to
`AttributedType`.
Fix by keeping `AttrsForTypes` up to date after replacing `AutoType`.
Various fixes and additions to creduce-clang-crash.py
Some more additions to the script - mainly reducing the clang args after
the creduce run by removing them one by one and seeing if the crash
reproduces. Other things:
- remove the --crash flag when "fatal error" occurs
- fixed to read stack trace functions from the top
- run creduce on a copy of the original file
Kang Zhang [Fri, 29 Mar 2019 09:11:52 +0000 (09:11 +0000)]
[PowerPC] Add the support for __builtin_setrnd() in clang
Summary:
PowerPC64/PowerPC64le supports the builtin function __builtin_setrnd to set the floating point rounding mode. This function will use the least significant two bits of integer argument to set the floating point rounding mode.
double __builtin_setrnd(int mode);
The effective values for mode are:
0 - round to nearest
1 - round to zero
2 - round to +infinity
3 - round to -infinity
Note that the mode argument will modulo 4, so if the int argument is greater than 3, it will only use the least significant two bits of the mode. Namely, builtin_setrnd(102)) is equal to builtin_setrnd(2).
Michael Liao [Fri, 29 Mar 2019 03:55:52 +0000 (03:55 +0000)]
[Sema] Fix a crash when nonnull checking
Summary:
- If a parameter is used, nonnull checking needs function prototype to
retrieve the corresponding parameter's attributes. However, at the
prototype substitution phase when a template is being instantiated,
expression may be created and checked without a fully specialized
prototype. Under such a scenario, skip nonnull checking on that
argument.
Akira Hatanaka [Fri, 29 Mar 2019 00:23:20 +0000 (00:23 +0000)]
[CodeGen][ObjC] Adjust the addresses passed to calls to synthesized
copy/move constructor/assignment operator functions for non-trivial C
structs.
This commit fixes a bug where the offset of struct fields weren't being
taken into account when computing the addresses passed to calls to the
special functions.
For example, the copy constructor for S1 (__copy_constructor_8_8_s0_s8)
would pass the start addresses of the destination and source structs to
the call to S0's copy constructor (_copy_constructor_8_8_s0) without
adding the offset of field f1 to the addresses.
Alexey Bataev [Thu, 28 Mar 2019 19:15:36 +0000 (19:15 +0000)]
[OPENMP]Add check for undefined behavior with thread allocators on
target and task-based directives.
According to OpenMP 5.0, 2.11.4 allocate Clause, Restrictions, For task,
taskloop or target directives, allocation requests to memory allocators
with the trait access set to thread result in unspecified behavior.
Patch introduces a check for omp_thread_mem_alloc predefined allocator
on target- and trask-based directives.
Shoaib Meenai [Thu, 28 Mar 2019 17:01:20 +0000 (17:01 +0000)]
[CodeGen] Add additional mangling for struct members of non trivial structs
In https://bugs.llvm.org/show_bug.cgi?id=41206 we observe bad codegen
when embedding a non-trivial C struct within a C struct. This is due to
the fact that name mangling for non-trivial structs marks the two
structs as identical. This diff contains a fix for this issue.
Adam Balogh [Thu, 28 Mar 2019 13:05:59 +0000 (13:05 +0000)]
[Analyzer] Constraint Manager - Calculate Effective Range for Differences
Since rL335814, if the constraint manager cannot find a range set for `A - B`
(where `A` and `B` are symbols) it looks for a range for `B - A` and returns
it negated if it exists. However, if a range set for both `A - B` and `B - A`
is stored then it only returns the first one. If we both use `A - B` and
`B - A`, these expressions behave as two totally unrelated symbols. This way
we miss some useful deductions which may lead to false negatives or false
positives.
This tiny patch changes this behavior: if the symbolic expression the
constraint manager is looking for is a difference `A - B`, it tries to
retrieve the range for both `A - B` and `B - A` and if both exists it returns
the intersection of range `A - B` and the negated range of `B - A`. This way
every time a checker applies new constraints to the symbolic difference or to
its negated it always affects both the original difference and its negated.
Fangrui Song [Thu, 28 Mar 2019 08:24:00 +0000 (08:24 +0000)]
[Driver] Allow -gsplit-dwarf on ELF OSes other than Linux and Fuchsia
In gcc, -gsplit-dwarf is handled in gcc/gcc.c as a spec
(ASM_FINAL_SPEC): objcopy --extract-dwo + objcopy --strip-dwo. In
gcc/opts.c, -gsplit_dwarf has the same semantic of a -g. Except for the
availability of the external command 'objcopy', nothing precludes the
feature working on other ELF OSes. llvm doesn't use objcopy, so it doesn't
have to exclude other OSes.
Shafik Yaghmour [Wed, 27 Mar 2019 17:47:36 +0000 (17:47 +0000)]
[ASTImporter] Fix IsStructuralMatch specialization for EnumDecl to prevent re-importing an EnumDecl while trying to complete it
Summary:
We may try and re-import an EnumDecl while trying to complete it in IsStructuralMatch(...) specialization for EnumDecl. This change mirrors a similar fix for the specialization for RecordDecl.
Erik Pilkington [Tue, 26 Mar 2019 23:21:19 +0000 (23:21 +0000)]
[Sema] Fix an assert when a block captures a constexpr local
MarkVarDeclODRUsed indirectly calls captureInBlock, which creates a copy
expression. The copy expression is insulated in it's own
ExpressionEvaluationContext, so it saves, mutates, and restores MaybeODRUseExprs
as CleanupVarDeclMarking is iterating through it, leading to a crash. Fix this
by iterating through a local copy of MaybeODRUseExprs.
Basic: Return a reference from FileManager::getVirtualFileSystem, NFC
FileManager constructs a VFS in its constructor if it isn't passed one,
and there's no way to reset it. Make that contract clear by returning a
reference from its accessor.
Remove CompilerInstance::VirtualFileSystem and
CompilerInstance::setVirtualFileSystem, instead relying on the VFS in
the FileManager. CompilerInstance and its clients already went to some
trouble to make these match. Now they are guaranteed to match.
As part of this, I added a VFS parameter (defaults to nullptr) to
CompilerInstance::createFileManager, to avoid repeating construction
logic in clients that just wanted to customize the VFS.
Shoaib Meenai [Tue, 26 Mar 2019 22:16:53 +0000 (22:16 +0000)]
[cmake] Reset variable before using it
A bunch of macros use the same variable name, and since CMake macros
don't get their own scope, the value persists across macro invocations,
and we can end up exporting targets which shouldn't be exported. Clear
the variable before each use to avoid this.
Converting these macros to functions would also help, since it would
avoid the variable leaking into its parent scope, and that's something I
plan to follow up with. It won't fully address the problem, however,
since functions still inherit variables from their parent scopes, so if
someone in the parent scope just happened to use the same variable name
we'd still have the same issue.
Jessica Paquette [Tue, 26 Mar 2019 21:22:42 +0000 (21:22 +0000)]
Make -mno-outline pass -enable-machine-outliner=never to ld in LTO
Since AArch64 has default outlining behaviour, we need to make sure that
-mno-outline is actually passed along to the linker in this case. Otherwise,
it will run by default on minsize functions even when -mno-outline is specified.
Also fix the darwin-ld test for this, which wasn't actually doing anything.
Artem Dergachev [Tue, 26 Mar 2019 00:36:53 +0000 (00:36 +0000)]
[CFG] [analyzer] pr41142: C++17: Skip transparent InitListExprs in ExprEngine.
r356634 didn't fix all the problems caused by r356222 - even though simple
constructors involving transparent init-list expressions are now evaluated
precisely, many more complicated constructors aren't, for other reasons.
The attached test case is an example of a constructor that will never be
evaluated precisely - simply because there isn't a constructor there (instead,
the program invokes run-time undefined behavior by returning without a return
statement that should have constructed the return value).
Fix another part of the problem for such situations: evaluate transparent
init-list expressions transparently, so that to avoid creating ill-formed
"transparent" nonloc::CompoundVals.
Reid Kleckner [Mon, 25 Mar 2019 23:20:18 +0000 (23:20 +0000)]
[MS] Add frontend support for __declspec(allocator)
The intention is to add metadata to direct call sites of functions
marked with __declspec(allocator), which will ultimately result in some
S_HEAPALLOCSITE debug info records when emitting codeview.
Bruno Ricci [Mon, 25 Mar 2019 21:37:10 +0000 (21:37 +0000)]
[Sema] Don't check for array bounds when the types in the base expression are dependent
Bail-out of CheckArrayAccess when the types of the base expression before
and after eventual casts are dependent. We will get another chance to check
for array bounds during instantiation. Fixes PR41087.
projects / clang / log