Summary:
The previous implementation misses an opportunity to apply NRVO (Named Return Value
Optimization) below. That discourages user to write early return code.
```
struct Foo {};
Foo f(bool b) {
if (b)
return Foo();
Foo oo;
return oo;
}
```
That is, we can/should apply RVO for a local variable if:
* It's directly returned by at least one return statement.
* And, all reachable return statements in its scope returns the variable directly.
While, the previous implementation disables the RVO in a scope if there are multiple return
statements that refers different variables.
On the new algorithm, local variables are in NRVO_Candidate state at first, and a return
statement changes it to NRVO_Disabled for all visible variables but the return statement refers.
Then, at the end of the function AST traversal, NRVO is enabled for variables in NRVO_Candidate
state and refers from at least one return statement.
Reviewers: rsmith
Reviewed By: rsmith
Subscribers: xbolva00, Quuxplusone, arthur.j.odwyer, cfe-commits
Differential Revision: https://reviews.llvm.org/D47067
llvm-svn: 333500
Summary: The blob data is unaligned, so we also should read it as such. Should fix the random failures with the sanitizer builds.
Reviewers: rsmith, v.g.vassilev
Reviewed By: v.g.vassilev
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D47247
llvm-svn: 333069
Provide some free functions to reduce verbosity of endian-writing
a single value, and replace the endianness template parameter with
a field.
Part of PR37466.
Differential Revision: https://reviews.llvm.org/D47032
llvm-svn: 332757
For example, given:
void fn() {
struct T *p0;
struct T { int i; } *p1;
}
-ast-print produced:
void fn() {
struct T { int i; } *p0;
struct T { int i; } *p1;
}
Compiling that fails with a redefinition error.
Given:
void fn() {
struct T *p0;
struct __attribute__((deprecated)) T *p1;
}
-ast-print dropped the attribute.
Details:
For a tag specifier (that is, struct/union/class/enum used as a type
specifier in a declaration) that was also a tag declaration (that is,
first occurrence of the tag) or tag redeclaration (that is, later
occurrence that specifies attributes or a member list), clang printed
the tag specifier as either (1) the full tag definition if one
existed, or (2) the first tag declaration otherwise. Redefinition
errors were sometimes introduced, as in the first example above. Even
when that was impossible because no member list was ever specified,
attributes were sometimes lost, thus changing semantics and
diagnostics, as in the second example above.
This patch fixes a major culprit for these problems. It does so by
creating an ElaboratedType with a new OwnedDecl member wherever an
occurrence of a tag type is a (re)declaration of that tag type.
PrintingPolicy's IncludeTagDefinition used to trigger printing of the
member list, attributes, etc. for a tag specifier by using a tag
(re)declaration selected as described above. Now, it triggers the
same thing except it uses the tag (re)declaration stored in the
OwnedDecl. Of course, other tooling can now make use of the new
OwnedDecl as well.
Also, to be more faithful to the original source, this patch
suppresses printing of attributes inherited from previous
declarations.
Reviewed by: rsmith, aaron.ballman
Differential Revision: https://reviews.llvm.org/D45463
llvm-svn: 332281
This is similar to the LLVM change https://reviews.llvm.org/D46290.
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.
Patch produced by
for i in $(git grep -l '\@brief'); do perl -pi -e 's/\@brief //g' $i & done
for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done
Differential Revision: https://reviews.llvm.org/D46320
llvm-svn: 331834
FunctionProtoType.
We previously re-evaluated the expression each time we wanted to know whether
the type is noexcept or not. We now evaluate the expression exactly once.
This is not quite "no functional change": it fixes a crasher bug during AST
deserialization where we would try to evaluate the noexcept specification in a
situation where we have not deserialized sufficient portions of the AST to
permit such evaluation.
llvm-svn: 331428
This is not yet part of any C++ working draft, and so is controlled by the flag
-fchar8_t rather than a -std= flag. (The GCC implementation is controlled by a
flag with the same name.)
This implementation is experimental, and will be removed or revised
substantially to match the proposal as it makes its way through the C++
committee.
llvm-svn: 331244
Support for ObjC/C ODR-like semantics with structural equivalence
checking was added back in r306918. There enums are handled and also
checked for structural equivalence. However, at use time of
EnumConstantDecl, support was missing for preventing ambiguous
name lookup.
Add the missing bits for properly merging EnumConstantDecl.
rdar://problem/38374569
llvm-svn: 331232
When a '>>' token is split into two '>' tokens (in C++11 onwards), or (as an
extension) when we do the same for other tokens starting with a '>', we can't
just use a location pointing to the first '>' as the location of the split
token, because that would result in our miscomputing the length and spelling
for the token. As a consequence, for example, a refactoring replacing 'A<X>'
with something else would sometimes replace one character too many, and
similarly diagnostics highlighting a template-id source range would highlight
one character too many.
Fix this by creating an expansion range covering the first character of the
'>>' token, whose spelling is '>'. For this to work, we generalize the
expansion range of a macro FileID to be either a token range (the common case)
or a character range (used in this new case).
llvm-svn: 331155
During deserialization clang is currently missing the merging of
protocols into the canonical interface for the class extension.
This merging only currently happens during parsing and should also
be considered during deserialization.
rdar://problem/38724303
llvm-svn: 331063
This patch is a tweak of changyu's patch: https://reviews.llvm.org/D40381. It differs in that the recognition of the 'concept' token is moved into the machinery that recognizes declaration-specifiers - this allows us to leverage the attribute handling machinery more seamlessly.
See the test file to get a sense of the basic parsing that this patch supports.
There is much more work to be done before concepts are usable...
Thanks Changyu!
llvm-svn: 330794
Right now we only use this information in one place, immediately after
we calculate it, but it's still nice information to have. The Swift
project is going to use this to tidy up its "API notes" feature (see
past discussion on cfe-dev that never quite converged).
Reviewed by Bruno Cardoso Lopes.
llvm-svn: 330452
framework module SomeKitCore {
...
export_as SomeKit
}
Given the module above, while generting autolink information during
codegen, clang should to emit '-framework SomeKitCore' only if SomeKit
was not imported in the relevant TU, otherwise it should use '-framework
SomeKit' instead.
rdar://problem/38269782
llvm-svn: 330152
Summary:
Clean carriage returns from lib/ and include/. NFC.
(I have to make this change locally in order for `git diff` to show sane output after I edit a file, so I might as well ask for it to be committed. I don't have commit privs myself.)
(Without this patch, `git rebase`ing any change involving SemaDeclCXX.cpp is a real nightmare. :( So while I have no right to ask for this to be committed, geez would it make my workflow easier if it were.)
Here's the command I used to reformat things. (Requires bash and OSX/FreeBSD sed.)
git grep -l $'\r' lib include | xargs sed -i -e $'s/\r//'
find lib include -name '*-e' -delete
Reviewers: malcolm.parsons
Reviewed By: malcolm.parsons
Subscribers: emaste, krytarowski, cfe-commits
Differential Revision: https://reviews.llvm.org/D45591
Patch by Arthur O'Dwyer.
llvm-svn: 330112
registers.
This patch fixes a bug in r328731 that caused structs transitively
containing __weak fields to be passed in registers. The patch replaces
the flag RecordDecl::CanPassInRegisters with a 2-bit enum that indicates
whether the struct or structs containing the struct are forced to be
passed indirectly.
This reapplies r329617. r329617 didn't specify the underlying type for
enum ArgPassingKind, which caused regression tests to fail on a windows
bot.
rdar://problem/39194693
Differential Revision: https://reviews.llvm.org/D45384
llvm-svn: 329635
registers.
This patch fixes a bug in r328731 that caused structs transitively
containing __weak fields to be passed in registers. The patch replaces
the flag RecordDecl::CanPassInRegisters with a 2-bit enum that indicates
whether the struct or structs containing the struct are forced to be
passed indirectly.
rdar://problem/39194693
llvm-svn: 329617
Found via codespell -q 3 -I ../clang-whitelist.txt
Where whitelist consists of:
archtype
cas
classs
checkk
compres
definit
frome
iff
inteval
ith
lod
methode
nd
optin
ot
pres
statics
te
thru
Patch by luzpaz! (This is a subset of D44188 that applies cleanly with a few
files that have dubious fixes reverted.)
Differential revision: https://reviews.llvm.org/D44188
llvm-svn: 329399
layout" rules.
The new rules say that a standard-layout struct has its first non-static
data member and all base classes at offset 0, and consider a class to
not be standard-layout if that would result in multiple subobjects of a
single type having the same address.
We track "is C++11 standard-layout class" separately from "is
standard-layout class" so that the ABIs that need this information can
still use it.
Differential Revision: https://reviews.llvm.org/D45176
llvm-svn: 329332
The AST for the fragment
```
@interface I
@end
template <typename>
void decode(I *p) {
for (I *k in p) {}
}
void decode(I *p) {
decode<int>(p);
}
```
differs heavily when templatized and non-templatized:
```
|-FunctionTemplateDecl 0x7fbfe0863940 <line:4:1, line:7:1> line:5:6 decode
| |-TemplateTypeParmDecl 0x7fbfe0863690 <line:4:11> col:11 typename depth 0 index 0
| |-FunctionDecl 0x7fbfe08638a0 <line:5:1, line:7:1> line:5:6 decode 'void (I *__strong)'
| | |-ParmVarDecl 0x7fbfe08637a0 <col:13, col:16> col:16 referenced p 'I *__strong'
| | `-CompoundStmt 0x7fbfe0863b88 <col:19, line:7:1>
| | `-ObjCForCollectionStmt 0x7fbfe0863b50 <line:6:3, col:20>
| | |-DeclStmt 0x7fbfe0863a50 <col:8, col:13>
| | | `-VarDecl 0x7fbfe08639f0 <col:8, col:11> col:11 k 'I *const __strong'
| | |-ImplicitCastExpr 0x7fbfe0863a90 <col:16> 'I *' <LValueToRValue>
| | | `-DeclRefExpr 0x7fbfe0863a68 <col:16> 'I *__strong' lvalue ParmVar 0x7fbfe08637a0 'p' 'I *__strong'
| | `-CompoundStmt 0x7fbfe0863b78 <col:19, col:20>
| `-FunctionDecl 0x7fbfe0863f80 <line:5:1, line:7:1> line:5:6 used decode 'void (I *__strong)'
| |-TemplateArgument type 'int'
| |-ParmVarDecl 0x7fbfe0863ef8 <col:13, col:16> col:16 used p 'I *__strong'
| `-CompoundStmt 0x7fbfe0890cf0 <col:19, line:7:1>
| `-ObjCForCollectionStmt 0x7fbfe0890cc8 <line:6:3, col:20>
| |-DeclStmt 0x7fbfe0890c70 <col:8, col:13>
| | `-VarDecl 0x7fbfe0890c00 <col:8, col:11> col:11 k 'I *__strong' callinit
| | `-ImplicitValueInitExpr 0x7fbfe0890c60 <<invalid sloc>> 'I *__strong'
| |-ImplicitCastExpr 0x7fbfe0890cb0 <col:16> 'I *' <LValueToRValue>
| | `-DeclRefExpr 0x7fbfe0890c88 <col:16> 'I *__strong' lvalue ParmVar 0x7fbfe0863ef8 'p' 'I *__strong'
| `-CompoundStmt 0x7fbfe0863b78 <col:19, col:20>
```
Note how in the instantiated version ImplicitValueInitExpr unexpectedly appears.
While objects are auto-initialized under ARC, it does not make sense to
have an initializer for a for-loop variable, and it makes even less
sense to have such a different AST for instantiated and non-instantiated
version.
Digging deeper, I have found that there are two separate Sema* files for
dealing with templates and for dealing with non-templatized code.
In a non-templatized version, an initialization was performed only for
variables which are not loop variables for an Objective-C loop and not
variables for a C++ for-in loop:
```
if (FRI && (Tok.is(tok::colon) || isTokIdentifier_in())) {
bool IsForRangeLoop = false;
if (TryConsumeToken(tok::colon, FRI->ColonLoc)) {
IsForRangeLoop = true;
if (Tok.is(tok::l_brace))
FRI->RangeExpr = ParseBraceInitializer();
else
FRI->RangeExpr = ParseExpression();
}
Decl *ThisDecl = Actions.ActOnDeclarator(getCurScope(), D);
if (IsForRangeLoop)
Actions.ActOnCXXForRangeDecl(ThisDecl);
Actions.FinalizeDeclaration(ThisDecl);
D.complete(ThisDecl);
return Actions.FinalizeDeclaratorGroup(getCurScope(), DS, ThisDecl);
}
SmallVector<Decl *, 8> DeclsInGroup;
Decl *FirstDecl = ParseDeclarationAfterDeclaratorAndAttributes(
D, ParsedTemplateInfo(), FRI);
```
However the code in SemaTemplateInstantiateDecl was inconsistent,
guarding only against C++ for-in loops.
rdar://38391075
Differential Revision: https://reviews.llvm.org/D44989
llvm-svn: 328749
ObjC and ObjC++ pass non-trivial structs in a way that is incompatible
with each other. For example:
typedef struct {
id f0;
__weak id f1;
} S;
// this code is compiled in c++.
extern "C" {
void foo(S s);
}
void caller() {
// the caller passes the parameter indirectly and destructs it.
foo(S());
}
// this function is compiled in c.
// 'a' is passed directly and is destructed in the callee.
void foo(S a) {
}
This patch fixes the incompatibility by passing and returning structs
with __strong or weak fields using the C ABI in C++ mode. __strong and
__weak fields in a struct do not cause the struct to be destructed in
the caller and __strong fields do not cause the struct to be passed
indirectly.
Also, this patch fixes the microsoft ABI bug mentioned here:
https://reviews.llvm.org/D41039?id=128767#inline-364710
rdar://problem/38887866
Differential Revision: https://reviews.llvm.org/D44908
llvm-svn: 328731
r327219 added wrappers to std::sort which randomly shuffle the container before
sorting. This will help in uncovering non-determinism caused due to undefined
sorting order of objects having the same key.
To make use of that infrastructure we need to invoke llvm::sort instead of
std::sort.
llvm-svn: 328636
During reading C++ definition data for lambda we can access
CXXRecordDecl representing lambda before we finished reading the
definition data. This can happen by reading a captured variable which is
VarDecl, then reading its decl context which is CXXMethodDecl `operator()`,
then trying to merge redeclarable methods and accessing
enclosing CXXRecordDecl. The call stack looks roughly like
VisitCXXRecordDecl
ReadCXXRecordDefinition
VisitVarDecl
VisitCXXMethodDecl
mergeRedeclarable
getPrimaryContextForMerging
If we add fake definition data at this point, later we'll hit the assertion
Assertion failed: (!DD.IsLambda && !MergeDD.IsLambda && "faked up lambda definition?"), function MergeDefinitionData, file clang/lib/Serialization/ASTReaderDecl.cpp, line 1675.
The fix is to assign definition data before reading it. Fixes PR32556.
rdar://problem/37461072
Reviewers: rsmith, bruno
Reviewed By: rsmith
Subscribers: cfe-commits, jkorous-apple, aprantl
Differential Revision: https://reviews.llvm.org/D43494
llvm-svn: 328153
source expressions when iterating over a PseudoObjectExpr's semantic
subexpression list.
Previously the loop in emitPseudoObjectExpr would emit the IR for each
OpaqueValueExpr that was in a PseudoObjectExpr's semantic-form
expression list and use the result when the OpaqueValueExpr later
appeared in other expressions. This caused an assertion failure when
AggExprEmitter tried to copy the result of an OpaqueValueExpr and the
copied type didn't have trivial copy/move constructors or assignment
operators.
This patch adds flag IsUnique to OpaqueValueExpr which indicates it is a
unique reference to its source expression (it is not used in multiple
places). The loop in emitPseudoObjectExpr ignores OpaqueValueExprs that
are unique and CodeGen visitors simply traverse the source expressions
of such OpaqueValueExprs.
rdar://problem/34363596
Differential Revision: https://reviews.llvm.org/D39562
llvm-svn: 327939
This patch uses the infrastructure added in r326307 for enabling
non-trivial fields to be declared in C structs to allow __weak fields in
C structs in ARC.
This recommits r327206, which was reverted because it caused
module-enabled builders to fail. I discovered that the
CXXRecordDecl::CanPassInRegisters flag wasn't being set correctly in
some cases after I moved it to RecordDecl.
Thanks to Eric Liu for helping me investigate the bug.
rdar://problem/33599681
https://reviews.llvm.org/D44095
llvm-svn: 327870
The patch adds nocf_check target independent attribute for disabling checks that were enabled by cf-protection flag.
The attribute can be appertained to functions and function pointers.
Attribute name follows GCC's similar attribute name.
Differential Revision: https://reviews.llvm.org/D41880
llvm-svn: 327768
This patch uses the infrastructure added in r326307 for enabling
non-trivial fields to be declared in C structs to allow __weak fields in
C structs in ARC.
rdar://problem/33599681
Differential Revision: https://reviews.llvm.org/D44095
llvm-svn: 327206
When parsing comments, for example, for -Wdocumentation, slightly different
behaviour occurs when -fparse-all-comments is specified. However, these
differences are subtle:
1. All comments are saved during parsing, regardless of whether they are doc
comments or not.
2. "Maybe-doc" comments, like <, !, etc, are saved as such, instead of marking
them as ordinary comments. The maybe-doc type of comment is never saved
otherwise. (Warning on these is the impetus of -Wdocumentation.)
3. All comments are treated as doc comments in ASTContext, even if they are ordinary.
This change moves the logic for checking CommentOptions.ParseAllComments closer
to where it has an effect. The overall logic is unchanged, but checks of the
ParseAllComments flag are now done where the effect will be clearer.
Subscribers: cfe-commits
llvm-svn: 326512
Original change:
[NFC] Move CommentOpts checks to the call sites that depend on it.
When parsing comments, for example, for -Wdocumentation, slightly different
behaviour occurs when -fparse-all-comments is specified. However, these
differences are subtle:
1. All comments are saved during parsing, regardless of whether they are doc comments or not.
2. "Maybe-doc" comments, like //<, //!, etc, are saved as such, instead of marking them as ordinary comments. The maybe-doc type of comment is never saved otherwise. (Warning on these is the impetus of -Wdocumentation.)
3. All comments are treated as doc comments in ASTContext, even if they are ordinary.
This change moves the logic for checking CommentOptions.ParseAllComments closer
to where it has an effect. The overall logic is unchanged, but checks of the
ParseAllComments flag are now done where the effect will be clearer.
llvm-svn: 326508
When parsing comments, for example, for -Wdocumentation, slightly different
behaviour occurs when -fparse-all-comments is specified. However, these
differences are subtle:
1. All comments are saved during parsing, regardless of whether they are doc
comments or not.
2. "Maybe-doc" comments, like //<, //!, etc, are saved as such, instead of
marking them as ordinary comments. The maybe-doc type of comment is never
saved otherwise. (Warning on these is the impetus of -Wdocumentation.)
3. All comments are treated as doc comments in ASTContext, even if they are
ordinary.
This change moves the logic for checking CommentOptions.ParseAllComments closer
to where it has an effect. The overall logic is unchanged, but checks of the
ParseAllComments flag are now done where the effect will be clearer.
Reviewers: rsmith
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D43663
llvm-svn: 326501
So I wrote a clang-tidy check to lint out redundant `isa`, `cast`, and
`dyn_cast`s for fun. This is a portion of what it found for clang; I
plan to do similar cleanups in LLVM and other subprojects when I find
time.
Because of the volume of changes, I explicitly avoided making any change
that wasn't highly local and obviously correct to me (e.g. we still have
a number of foo(cast<Bar>(baz)) that I didn't touch, since overloading
is a thing and the cast<Bar> did actually change the type -- just up the
class hierarchy).
I also tried to leave the types we were cast<>ing to somewhere nearby,
in cases where it wasn't locally obvious what we were dealing with
before.
llvm-svn: 326416
This patch removes the HashString function from StringExtraces and
replaces its uses with calls to djbHash from DJB.h.
This change is *almost* NFC. While the algorithm is identical, the
djbHash implementation in StringExtras used 0 as its default seed while
the implementation in DJB uses 5381. The latter has been shown to result
in less collisions and improved avalanching and is used by the DWARF
accelerator tables.
Because some test were implicitly relying on the hash order, I've
reverted to using zero as a seed for the following two files:
lld/include/lld/Core/SymbolTable.h
llvm/lib/Support/StringMap.cpp
Differential revision: https://reviews.llvm.org/D43615
llvm-svn: 326091
It looks like some of our tests depend on the ordering of hashed values.
I'm reverting my changes while I try to reproduce and fix this locally.
Failing builds:
lab.llvm.org:8011/builders/lld-x86_64-darwin13/builds/18388
lab.llvm.org:8011/builders/clang-cmake-x86_64-sde-avx512-linux/builds/6743
lab.llvm.org:8011/builders/llvm-clang-lld-x86_64-scei-ps4-windows10pro-fast/builds/15607
llvm-svn: 326082
This removes the HashString function from StringExtraces and replaces
its uses with calls to djbHash from DJB.h
This is *almost* NFC. While the algorithm is identical, the djbHash
implementation in StringExtras used 0 as its seed while the
implementation in DJB uses 5381. The latter has been shown to result in
less collisions and improved avalanching.
https://reviews.llvm.org/D43615
(cherry picked from commit 77f7f965bc9499a9ae768a296ca5a1f7347d1d2c)
llvm-svn: 326081
diagnostic settings using _Pragma within a macro.
The AST writer had previously been assuming that all diagnostic state
transitions would occur within a FileID corresponding to a file. When a
diagnostic state change occured within a macro, it was unable to form a
location for that state change and would instead corrupt the diagnostic state
of the "root" node (and thus that of the main compilation).
Also introduce a "#pragma clang __debug diag_mapping" debugging utility
that I added to track this issue down.
llvm-svn: 324695
The 'trivial_abi' attribute can be applied to a C++ class, struct, or
union. It makes special functions of the annotated class (the destructor
and copy/move constructors) to be trivial for the purpose of calls and,
as a result, enables the annotated class or containing classes to be
passed or returned using the C ABI for the underlying type.
When a type that is considered trivial for the purpose of calls despite
having a non-trivial destructor (which happens only when the class type
or one of its subobjects is a 'trivial_abi' class) is passed to a
function, the callee is responsible for destroying the object.
For more background, see the discussions that took place on the mailing
list:
http://lists.llvm.org/pipermail/cfe-dev/2017-November/055955.htmlhttp://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20180101/thread.html#214043
rdar://problem/35204524
Differential Revision: https://reviews.llvm.org/D41039
llvm-svn: 324269
TemplateTemplateParmDecls of alias templates ended-up serialized as 'file-level decls' which was causing a crash while trying to index a PCH/module file that contained them.
Commit makes sure TemplateTemplateParmDecls are not recorded as such kind of decls.
Fixes crash of rdar://36608297
Differential Revision: https://reviews.llvm.org/D42588
llvm-svn: 323549
The skipped preprocessor ranges are now serialized in the AST PCH file. This fixes, for example, libclang's clang_getSkippedRanges() returning zero ranges after reparsing a translation unit.
Differential Revision: https://reviews.llvm.org/D20124
llvm-svn: 322503
