Summary:
This is the second attempt of r333500 (Update NRVO logic to support early return).
The previous one was reverted for a miscompilation for an incorrect NRVO set up on templates such as:
```
struct Foo {};
template <typename T>
T bar() {
T t;
if (false)
return T();
return t;
}
```
Where, `t` is marked as non-NRVO variable before its instantiation. However, while its instantiation, it's left an NRVO candidate, turned into an NRVO variable later.
Reviewers: rsmith
Reviewed By: rsmith
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D47586
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@335019 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@333500 91177308-0d34-0410-b5e6-96231b3b80d8
The fixit is actively harmful, as it encourages developers to ignore the
warning and to write unsafe code.
It is almost impossible to write safe code while capturing autoreleasing
variables in the block, as in order to check that the block is never
called in the autoreleasing pool the developer has to check the
transitive closure of all potential callers of the block.
Differential Revision: https://reviews.llvm.org/D46778
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@332288 91177308-0d34-0410-b5e6-96231b3b80d8
For 'x::template y', consistently give a "no member named 'y' in 'x'"
diagnostic if there is no such member, and give a 'template keyword not
followed by a template' name error if there is such a member but it's not a
template. In the latter case, add a note pointing at the non-template.
Don't suggest inserting a 'template' keyword in 'X::Y<' if X is dependent
if the lookup of X::Y was actually not a dependent lookup and found only
non-templates.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@332076 91177308-0d34-0410-b5e6-96231b3b80d8
Added string literal helper function to obtain the type
attributed by a constant address space.
Also fixed predefind __func__ expr to use the helper
to constract the string literal correctly.
Differential Revision: https://reviews.llvm.org/D46049
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@331877 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@331834 91177308-0d34-0410-b5e6-96231b3b80d8
This patch addresses some mostly trivial post-commit review comments received
on r331677.
Additionally, this patch fixes an assertion in `getNarrowingKind` caused by
the use of an uninitialized value from `checkThreeWayNarrowingConversion`.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@331707 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This patch tackles long hanging fruit for the builtin operator<=> expressions. It is currently needs some cleanup before landing, but I want to get some initial feedback.
The main changes are:
* Lookup, build, and store the required standard library types and expressions in `ASTContext`. By storing them in ASTContext we don't need to store (and duplicate) the required expressions in the BinaryOperator AST nodes.
* Implement [expr.spaceship] checking, including diagnosing narrowing conversions.
* Implement `ExprConstant` for builtin spaceship operators.
* Implement builitin operator<=> support in `CodeGenAgg`. Initially I emitted the required comparisons using `ScalarExprEmitter::VisitBinaryOperator`, but this caused the operand expressions to be emitted once for every required cmp.
* Implement [builtin.over] with modifications to support the intent of P0946R0. See the note on `BuiltinOperatorOverloadBuilder::addThreeWayArithmeticOverloads` for more information about the workaround.
Reviewers: rsmith, aaron.ballman, majnemer, rnk, compnerd, rjmccall
Reviewed By: rjmccall
Subscribers: rjmccall, rsmith, aaron.ballman, junbuml, mgorny, cfe-commits
Differential Revision: https://reviews.llvm.org/D45476
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@331677 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@331244 91177308-0d34-0410-b5e6-96231b3b80d8
template arguments.
This fixes some cases where we'd incorrectly accept "A::template B" when B is a
kind of template that requires template arguments (in particular, a variable
template or a concept).
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@331013 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
It seems there isn't much enthusiasm for `-wtest` D45685.
This is more conservative version, which i had in the very first
revision of D44883, but that 'erroneously' got removed because of the review.
**Based on some [irc] discussions, it must really be documented that
we want all the new diagnostics to have their own flags, to ease
rollouts, transitions, etc.**
Please do note that i'm only adding `-Wno-self-assign-overloaded`,
but not `-Wno-self-assign-field-overloaded`, because i'm honestly
not aware of any false-positives from the `-field` variant,
but i can just as easily add it if wanted.
https://reviews.llvm.org/D44883#1068561
Reviewers: dblaikie, aaron.ballman, thakis, rjmccall, rsmith
Reviewed By: dblaikie
Subscribers: Quuxplusone, chandlerc, cfe-commits
Differential Revision: https://reviews.llvm.org/D45766
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@330651 91177308-0d34-0410-b5e6-96231b3b80d8
The current support of the feature produces only 2 lines in report:
-Some general Code Generation Time;
-Total time of Backend Consumer actions.
This patch extends Clang time report with new lines related to Preprocessor, Include Filea Search, Parsing, etc.
Differential Revision: https://reviews.llvm.org/D43578
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@329684 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This has just bit me, so i though it would be nice to avoid that next time :)
Motivational case:
https://godbolt.org/g/cq9UNk
Basically, it's likely to happen if you don't like shadowing issues,
and use `-Wshadow` and friends. And it won't be diagnosed by clang.
The reason is, these self-assign diagnostics only work for builtin assignment
operators. Which makes sense, one could have a very special operator=,
that does something unusual in case of self-assignment,
so it may make sense to not warn on that.
But while it may be intentional in some cases, it may be a bug in other cases,
so it would be really great to have some diagnostic about it...
Reviewers: aaron.ballman, rsmith, rtrieu, nikola, rjmccall, dblaikie
Reviewed By: rjmccall
Subscribers: EricWF, lebedev.ri, thakis, Quuxplusone, cfe-commits
Differential Revision: https://reviews.llvm.org/D44883
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@329493 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@329399 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts r328795 which introduced an issue with referencing __global__
function templates. More details in the original review D44747.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@329099 91177308-0d34-0410-b5e6-96231b3b80d8
Deprecation replacement can be any text but if it looks like a name of
ObjC method and has the same number of arguments as original method,
replace all slot names so after applying a fix-it you have valid code.
rdar://problem/36660853
Reviewers: aaron.ballman, erik.pilkington, rsmith
Reviewed By: erik.pilkington
Subscribers: cfe-commits, jkorous-apple
Differential Revision: https://reviews.llvm.org/D44589
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@328807 91177308-0d34-0410-b5e6-96231b3b80d8
The diagnostic system for Clang can already handle many AST nodes. Instead
of converting them to strings first, just hand the AST node directly to
the diagnostic system and let it handle the output. Minor changes in some
diagnostic output.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@328688 91177308-0d34-0410-b5e6-96231b3b80d8
This relands r326965.
There was a null dereference in typo correction that was triggered in
Sema/diagnose_if.c. We are not always in a function scope when doing
typo correction. The fix is to add a null check.
LLVM's optimizer made it hard to find this bug. I wrote it up in a
not-very-well-editted blog post here:
http://qinsb.blogspot.com/2018/03/ub-will-delete-your-null-checks.html
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@327334 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts r326965. It seems to have caused repeating test failures in
clang/test/Sema/diagnose_if.c on some buildbots.
I cannot reproduce the problem, and it's not immediately obvious what
the problem is, so let's revert to green.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@326974 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Before this patch, Sema pre-allocated a FunctionScopeInfo and kept it in
the first, always present element of the FunctionScopes stack. This
meant that Sema::getCurFunction would return a pointer to this
pre-allocated object when parsing code outside a function body. This is
pretty much always a bug, so this patch moves the pre-allocated object
into a separate unique_ptr. This should make bugs like PR36536 a lot
more obvious.
As you can see from this patch, there were a number of places that
unconditionally assumed they were always called inside a function.
However, there are also many places that null checked the result of
getCurFunction(), so I think this is a reasonable direction.
Reviewers: rsmith
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D44039
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@326965 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This provides no measurable build speedup, but it reinstates an
optimization from r112038 that was lost in r179618. It requires moving
CapturedScopeInfo::Capture out to clang::sema, which might be too
general since we have plenty of other Capture records in BlockDecl and
other AST nodes.
Reviewers: rjmccall
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D44221
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@326957 91177308-0d34-0410-b5e6-96231b3b80d8
This makes it easier to debug crashes and hangs in block functions since
users can easily find out where the block is called from. The option
doesn't disable tail-calls from non-escaping blocks since non-escaping
blocks are not as hard to debug as escaping blocks.
rdar://problem/35758207
Differential Revision: https://reviews.llvm.org/D43841
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@326530 91177308-0d34-0410-b5e6-96231b3b80d8
ARC mode.
Declaring __strong pointer fields in structs was not allowed in
Objective-C ARC until now because that would make the struct non-trivial
to default-initialize, copy/move, and destroy, which is not something C
was designed to do. This patch lifts that restriction.
Special functions for non-trivial C structs are synthesized that are
needed to default-initialize, copy/move, and destroy the structs and
manage the ownership of the objects the __strong pointer fields point
to. Non-trivial structs passed to functions are destructed in the callee
function.
rdar://problem/33599681
Differential Revision: https://reviews.llvm.org/D41228
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@326307 91177308-0d34-0410-b5e6-96231b3b80d8
We should only ban this if long double is a double double. x86's 80 bit
long double is fine and supported by the backend.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@322779 91177308-0d34-0410-b5e6-96231b3b80d8
When parsing C++ type construction expressions with list initialization,
forward the locations of the braces to Sema.
Without these locations, the code coverage pass crashes on the given test
case, because the pass relies on getLocEnd() returning a valid location.
Here is what this patch does in more detail:
- Forwards init-list brace locations to Sema (ParseExprCXX),
- Builds an InitializationKind with these locations (SemaExprCXX), and
- Uses these locations for constructor initialization (SemaInit).
The remaining changes fall out of introducing a new overload for
creating direct-list InitializationKinds.
Testing: check-clang, and a stage2 coverage-enabled build of clang with
asserts enabled.
Differential Revision: https://reviews.llvm.org/D41921
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@322729 91177308-0d34-0410-b5e6-96231b3b80d8
This is not quite NFC: we don't perform the usual arithmetic conversions unless
we have an operand of arithmetic or enumeration type any more. This matches the
standard rule, but actually has no effect other than to marginally improve our
diagnostics for the non-arithmetic, non-enumeration cases (by not performing
integral promotions on one operand if the other is a pointer).
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@322024 91177308-0d34-0410-b5e6-96231b3b80d8
Check whether we are comparing the same entity, not merely the same
declaration, and don't assume that weak declarations resolve to distinct
entities.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@321976 91177308-0d34-0410-b5e6-96231b3b80d8
Adding the new enumerator forced a bunch more changes into this patch than I
would have liked. The -Wtautological-compare warning was extended to properly
check the new comparison operator, clang-format needed updating because it uses
precedence levels as weights for determining where to break lines (and several
operators increased their precedence levels with this change), thread-safety
analysis needed changes to build its own IL properly for the new operator.
All "real" semantic checking for this operator has been deferred to a future
patch. For now, we use the relational comparison rules and arbitrarily give
the builtin form of the operator a return type of 'void'.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@320707 91177308-0d34-0410-b5e6-96231b3b80d8
This commit fixes a bug in IRGen where it generates completely broken
code for __fp16 vectors on X86. For example when the following code is
compiled:
half4 hv0, hv1, hv2; // these are vectors of __fp16.
void foo221() {
hv0 = hv1 + hv2;
}
clang generates the following IR, in which two i16 vectors are added:
@hv1 = common global <4 x i16> zeroinitializer, align 8
@hv2 = common global <4 x i16> zeroinitializer, align 8
@hv0 = common global <4 x i16> zeroinitializer, align 8
define void @foo221() {
%0 = load <4 x i16>, <4 x i16>* @hv1, align 8
%1 = load <4 x i16>, <4 x i16>* @hv2, align 8
%add = add <4 x i16> %0, %1
store <4 x i16> %add, <4 x i16>* @hv0, align 8
ret void
}
To fix the bug, this commit uses the code committed in r314056, which
modified clang to promote and truncate __fp16 vectors to and from float
vectors in the AST. It also fixes another IRGen bug where a short value
is assigned to an __fp16 variable without any integer-to-floating-point
conversion, as shown in the following example:
__fp16 a;
short b;
void foo1() {
a = b;
}
@b = common global i16 0, align 2
@a = common global i16 0, align 2
define void @foo1() #0 {
%0 = load i16, i16* @b, align 2
store i16 %0, i16* @a, align 2
ret void
}
rdar://problem/20625184
Differential Revision: https://reviews.llvm.org/D40112
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@320215 91177308-0d34-0410-b5e6-96231b3b80d8
Also remove unnecessary initialization of out-parameters with this value, so
that MSan is able to catch errors appropriately.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@320212 91177308-0d34-0410-b5e6-96231b3b80d8
Private variables are completely redefined in the outlined regions, so
we don't need to capture them. Patch adds this behavior to the
target-based regions.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@320078 91177308-0d34-0410-b5e6-96231b3b80d8
While here, split the "point of instantiation changed" notification out from
it; these two really are orthogonal changes.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@319727 91177308-0d34-0410-b5e6-96231b3b80d8
Taiju Tsuiki