This is to support some analyses, like -Wunreachable-code, that
will need to recover the original unprunned CFG edges in order
to suppress issues that aren't really bugs in practice.
There are two important changes here:
- AdjacentBlock replaces CFGBlock* for CFG successors/predecessors.
This has the size of 2 pointers, instead of 1. This is unlikely
to have a significant memory impact on Sema since a single
CFG usually exists at one time, but could impact the memory
usage of the static analyzer. This could possibly be optimized
down to a single pointer with some cleverness.
- Predecessors can now contain null predecessors, which means
some analyses doing a reverse traversal will need to take into
account. This already exists for successors, which contain
successor slots for specific branch kinds (e.g., 'if') that
expect a fixed number of successors, even if a branch is
not reachable.
llvm-svn: 202325
In an expression like "new (a, b) Foo(x, y)", two things happen:
- Memory is allocated by calling a function named 'operator new'.
- The memory is initialized using the constructor for 'Foo'.
Currently the analyzer only models the second event, though it has special
cases for both the default and placement forms of operator new. This patch
is the first step towards properly modeling both events: it changes the CFG
so that the above expression now generates the following elements.
1. a
2. b
3. (CFGNewAllocator)
4. x
5. y
6. Foo::Foo
The analyzer currently ignores the CFGNewAllocator element, but the next
step is to treat that as a call like any other.
The CFGNewAllocator element is not added to the CFG for analysis-based
warnings, since none of them take advantage of it yet.
llvm-svn: 199123
Summary:
If a noreturn destructor is executed while returning a value from a function,
the resulting CFG has had two edges to the exit block. This crashed the analyzer,
because it expects that blocks with no terminators have only one outgoing edge.
I added code to avoid creating the second edge in this case.
PS: The crashes did not manifest themselves always, as usually the
NoReturnFunctionChecker would stop program evaluation before the analyzer hit
the assertion, but in the case of lifetime extended temporaries, the checker
failed to do that (which is a separate bug in itself).
Reviewers: jordan_rose
CC: cfe-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D1513
llvm-svn: 190125
This paves the way for adding support for modeling the destructor of a
region before it is deleted. The statement "delete <expr>" now generates
this series of CFG elements:
1. <expr>
2. [B1.1]->~Foo() (Implicit destructor)
3. delete [B1.1]
Patch by Karthik Bhat!
llvm-svn: 189828
This is an improved version of r186498. It enables ExprEngine to reason about
temporary object destructors. However, these destructor calls are never
inlined, since this feature is still broken. Still, this is sufficient to
properly handle noreturn temporary destructors.
Now, the analyzer correctly handles expressions like "a || A()", and executes the
destructor of "A" only on the paths where "a" evaluted to false.
Temporary destructor processing is still off by default and one has to
explicitly request it by setting cfg-temporary-dtors=true.
Reviewers: jordan_rose
CC: cfe-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D1259
llvm-svn: 189746
This builtin does not actually evaluate its arguments for side effects,
so we shouldn't include them in the CFG. In the analyzer, rely on the
constant expression evaluator to get the proper semantics, at least for
now. (In the future, we could get ambitious and try to provide path-
sensitive size values.)
In theory, this does pose a problem for liveness analysis: a variable can
be used within the __builtin_object_size argument expression but not show
up as live. However, it is very unlikely that such a value would be used
to compute the object size and not used to access the object in some way.
<rdar://problem/14760817>
llvm-svn: 188679
Add the back edge info by creating a basic block, marked as loop target. This is
consistent with how other loops are processed, but was omitted from
VisitObjCForCollectionStmt.
llvm-svn: 184617
Previously our edges were completely broken here; now, the final result
is a very simple set of edges in most cases: one up to the "for" keyword
for context, and one into the body of the loop. This matches the behavior
for ObjC for-in loops.
In the AST, however, CXXForRangeStmts are handled very differently from
ObjCForCollectionStmts. Since they are specified in terms of equivalent
statements in the C++ standard, we actually have implicit AST nodes for
all of the semantic statements. This makes evaluation very easy, but
diagnostic locations a bit trickier. Fortunately, the problem can be
generally defined away by marking all of the implicit statements as
part of the top-level for-range statement.
One of the implicit statements in a for-range statement is the declaration
of implicit iterators __begin and __end. The CFG synthesizes two
separate DeclStmts to match each of these decls, but until now these
synthetic DeclStmts weren't in the function's ParentMap. Now, the CFG
keeps track of its synthetic statements, and the AnalysisDeclContext will
make sure to add them to the ParentMap.
<rdar://problem/14038483>
llvm-svn: 183449
Consider the case where a SwitchStmt satisfied isAllEnumCasesCovered()
as well as having no cases at all (i.e. the enum it covers has no
enumerators).
In this case, we should add a successor to repair the CFG.
This fixes PR16212.
llvm-svn: 183237
Neither the compiler nor the analyzer are doing anything with non-VarDecl
decls in the CFG, and having them there creates extra nodes in the
analyzer's path diagnostics. Simplify the CFG (and the path edges) by
simply leaving them out. We can always add interesting decls back in when
they become relevant.
Note that this only affects decls declared in a DeclStmt, and then only
those that appear within a function body.
llvm-svn: 183157
This class is a StmtVisitor that distinguishes between block-level and
non-block-level statements in a CFG. However, it does so using a hard-coded
idea of which statements might be block-level, which probably isn't accurate
anymore. The only implementer of the CFGStmtVisitor hierarchy was the
analyzer's DeadStoresChecker, and the analyzer creates a linearized CFG
anyway (every non-trivial statement is a block-level statement).
This also allows us to remove the block-expr map ("BlkExprMap"), which
mapped statements to positions in the CFG. Apart from having a helper type
that really should have just been Optional<unsigned>, it was only being
used to ask /if/ a particular expression was block-level, for traversal
purposes in CFGStmtVisitor.
llvm-svn: 181945
The most common (non-buggy) case are where such objects are used as
return expressions in bool-returning functions or as boolean function
arguments. In those cases I've used (& added if necessary) a named
function to provide the equivalent (or sometimes negative, depending on
convenient wording) test.
DiagnosticBuilder kept its implicit conversion operator owing to the
prevalent use of it in return statements.
One bug was found in ExprConstant.cpp involving a comparison of two
PointerUnions (PointerUnion did not previously have an operator==, so
instead both operands were converted to bool & then compared). A test
is included in test/SemaCXX/constant-expression-cxx1y.cpp for the fix
(adding operator== to PointerUnion in LLVM).
llvm-svn: 181869
Add a CXXDefaultInitExpr, analogous to CXXDefaultArgExpr, and use it both in
CXXCtorInitializers and in InitListExprs to represent a default initializer.
There's an additional complication here: because the default initializer can
refer to the initialized object via its 'this' pointer, we need to make sure
that 'this' points to the right thing within the evaluation.
llvm-svn: 179958
This is an optional variant of the CFG. This allows analyses to model whether
or not a static initializer has run, e.g.:
static Foo x = bar();
For basic dataflow analysis in Sema we will just assume that the initializer
always runs. For the static analyzer we can use this branch to accurately
track whether or not initializers are on.
This patch just adds the (opt-in) functionality to the CFG. The
static analyzer still needs to be modified to adopt this feature.
llvm-svn: 178263
Use Optional<CFG*> where invalid states were needed previously. In the one case
where that's not possible (beginAutomaticObjDtorsInsert) just use a dummy
CFGAutomaticObjDtor.
Thanks for the help from Jordan Rose & discussion/feedback from Ted Kremenek
and Doug Gregor.
Post commit code review feedback on r175796 by Ted Kremenek.
llvm-svn: 175938
This is a more natural order of evaluation, and it is very important
for visualization in the static analyzer. Within Xcode, the arrows
will not jump from right to left, which looks very visually jarring.
It also provides a more natural location for dataflow-based diagnostics.
Along the way, we found a case in the analyzer diagnostics where we
needed to indicate that a variable was "captured" by a block.
-fsyntax-only timings on sqlite3.c show no visible performance change,
although this is just one test case.
Fixes <rdar://problem/13016513>
llvm-svn: 174447
it apart from [[gnu::noreturn]] / __attribute__((noreturn)), since their
semantics are not equivalent (for instance, we treat [[gnu::noreturn]] as
affecting the function type, whereas [[noreturn]] does not).
llvm-svn: 172691
First check only wrapped with i==8, second wrapped at i==2,8,18,28,...
This fix restores the intended behavior: i==8,18,28,...
Found with -fsanitize=integer.
llvm-svn: 171718
This code assigned the last created CFGBlock* to the variable 'Block',
which is a scratch variable which is null'ed out after a block is
completed. By assigning the last created block to 'Block', we start
editing a completed block, inserting CFGStmts that should be in
another block. This was the case with 'try'. The test case that
showed this had a while loop inside a 'try', and the logic before
the while loop was being included as part of the "condition block"
for the loop. This showed up as a bogus dead store, but could
have lots of implications.
Turns out this bug was replicated a few times within CFG.cpp, so
I went and fixed up those as well.
llvm-svn: 167788
While destructors will continue to not be inlined (unless the analyzer
config option 'c++-inlining' is set to 'destructors'), leaving them out
of the CFG is an incomplete model of the behavior of an object, and
can cause false positive warnings (like PR13751, now working).
Destructors for temporaries are still not on by default, since
(a) we haven't actually checked this code to be sure it's fully correct
(in particular, we probably need to be very careful with regard to
lifetime-extension when a temporary is bound to a reference,
C++11 [class.temporary]p5), and
(b) ExprEngine doesn't actually do anything when it sees a temporary
destructor in the CFG -- not even invalidate the object region.
To enable temporary destructors, set the 'cfg-temporary-dtors' analyzer
config option to '1'. The old -cfg-add-implicit-dtors cc1 option, which
controlled all implicit destructors, has been removed.
llvm-svn: 163264
A CXXDefaultArgExpr wraps an Expr owned by a ParmVarDecl belonging to the
called function. In general, ExprEngine and Environment ought to treat this
like a ParenExpr or other transparent wrapper expression, with the inside
expression evaluated first.
However, if we call the same function twice, we'd produce a CFG that contains
the same wrapped expression twice, and we're not set up to handle that. I've
added a FIXME to the CFG builder to come back to that, but meanwhile we can
at least handle expressions that don't need to be explicitly evaluated:
literals. This probably handles many common uses of default parameters:
true/false, null, etc.
Part of PR13385 / <rdar://problem/12156507>
llvm-svn: 162453
Also rename 'getCurrentBlockCounter()' to 'blockCount()'.
This ripples a bunch of code simplifications; mostly aesthetic,
but makes the code a bit tighter.
llvm-svn: 162349
a defaulted special member function until the exception specification is needed
(using the same criteria used for the delayed instantiation of exception
specifications for function temploids).
EST_Delayed is now EST_Unevaluated (using 1330's terminology), and, like
EST_Uninstantiated, carries a pointer to the FunctionDecl which will be used to
resolve the exception specification.
This is enabled for all C++ modes: it's a little faster in the case where the
exception specification isn't used, allows our C++11-in-C++98 extensions to
work, and is still correct for C++98, since in that mode the computation of the
exception specification can't fail.
The diagnostics here aren't great (in particular, we should include implicit
evaluation of exception specifications for defaulted special members in the
template instantiation backtraces), but they're not much worse than before.
Our approach to the problem of cycles between in-class initializers and the
exception specification for a defaulted default constructor is modified a
little by this change -- we now reject any odr-use of a defaulted default
constructor if that constructor uses an in-class initializer and the use is in
an in-class initialzer which is declared lexically earlier. This is a closer
approximation to the current draft solution in core issue 1351, but isn't an
exact match (but the current draft wording isn't reasonable, so that's to be
expected).
llvm-svn: 160847
short-circuiting when building the CFG. Also be sure to skip parens before
checking for the && / || special cases. Finally, fix some crashes in CFG
printing in the presence of calls to destructors for array of array of class
type.
llvm-svn: 160691
The CFG creates dummy DeclStmts with one Decl per statement, and it has
to do so from last to first in order to build the graph correctly.
llvm-svn: 160560
instead push the terminator for the branch down into the basic blocks of the subexpressions of '&&' and '||'
respectively. This eliminates some artifical control-flow from the CFG and results in a more
compact CFG.
Note that this patch only alters the branches 'while', 'if' and 'for'. This was complex enough for
one patch. The remaining branches (e.g., do...while) can be handled in a separate patch, but they
weren't immediately tackled because they were less important.
It is possible that this patch introduces some subtle bugs, particularly w.r.t. to destructor placement.
I've tried to audit these changes, but it is also known that the destructor logic needs some refinement
in the area of '||' and '&&' regardless (i.e., their are known bugs).
llvm-svn: 160218
This required moving the ctors for IntegerLiteral and FloatingLiteral out of
line which shouldn't change anything as they are usually called through Create
methods that are already out of line.
ASTContext::Deallocate has been a nop for a long time, drop it from ASTVector
and make it independent from ASTContext.h
Pass the StorageAllocator directly to AccessedEntity so it doesn't need to
have a definition of ASTContext around.
llvm-svn: 159718
In addition, I've made the pointer and reference typedef 'void' rather than T*
just so they can't get misused. I would've omitted them entirely but
std::distance likes them to be there even if it doesn't use them.
This rolls back r155808 and r155869.
Review by Doug Gregor incorporating feedback from Chandler Carruth.
llvm-svn: 158104
cases in switch statements. Also add a [[clang::fallthrough]] attribute, which
can be used to suppress the warning in the case of intentional fallthrough.
Patch by Alexander Kornienko!
The handling of C++11 attribute namespaces in this patch is temporary, and will
be replaced with a cleaner mechanism in a subsequent patch.
llvm-svn: 156086
filter_decl_iterator had a weird mismatch where both op* and op-> returned T*
making it difficult to generalize this filtering behavior into a reusable
library of any kind.
This change errs on the side of value, making op-> return T* and op* return
T&.
(reviewed by Richard Smith)
llvm-svn: 155808
We have a new flavor of exception specification, EST_Uninstantiated. A function
type with this exception specification carries a pointer to a FunctionDecl, and
the exception specification for that FunctionDecl is instantiated (if needed)
and used in the place of the function type's exception specification.
When a function template declaration with a non-trivial exception specification
is instantiated, the specialization's exception specification is set to this
new 'uninstantiated' kind rather than being instantiated immediately.
Expr::CanThrow has migrated onto Sema, so it can instantiate exception specs
on-demand. Also, any odr-use of a function triggers the instantiation of its
exception specification (the exception specification could be needed by IRGen).
In passing, fix two places where a DeclRefExpr was created but the corresponding
function was not actually marked odr-used. We used to get away with this, but
don't any more.
Also fix a bug where instantiating an exception specification which refers to
function parameters resulted in a crash. We still have the same bug in default
arguments, which I'll be looking into next.
This, plus a tiny patch to fix libstdc++'s common_type, is enough for clang to
parse (and, in very limited testing, support) all of libstdc++4.7's standard
headers.
llvm-svn: 154886
attached. Since we do not support any attributes which appertain to a statement
(yet), testing of this is necessarily quite minimal.
Patch by Alexander Kornienko!
llvm-svn: 154723
during construction of branches for chained logical operators.
This makes -fsyntax-only for test/Sema/many-logical-ops.c about 32x times faster.
With measuring SemaExpr.cpp I see differences below the noise level.
llvm-svn: 153297
as aborted, but didn't treat such cases as sinks in the ExplodedGraph.
Along the way, add basic support for CXXCatchStmt, expanding the set of code we actually analyze (hopefully correctly).
Fixes: <rdar://problem/10892489>
llvm-svn: 152468
analysis to make the AST representation testable. They are represented by a
new UserDefinedLiteral AST node, which is a sugared CallExpr. All semantic
properties, including full CodeGen support, are achieved for free by this
representation.
UserDefinedLiterals can never be dependent, so no custom instantiation
behavior is required. They are mangled as if they were direct calls to the
underlying literal operator. This matches g++'s apparent behavior (but not its
actual mangling, which is broken for literal-operator-ids).
User-defined *string* literals are now fully-operational, but the semantic
analysis is quite hacky and needs more work. No other forms of user-defined
literal are created yet, but the AST support for them is present.
This patch committed after midnight because we had already hit the quota for
new kinds of literal yesterday.
llvm-svn: 152211
block-level expr. Currently CXXConstructExpr is always added as a block-level
expr. This caused two problems for the analyzer (and potentially for the
CFG-based codegen).
1. We have no way to know whether a ctor call is base or complete.
2. We have no way to know the destination object being contructed.
llvm-svn: 147306
lifetimes have been extended via reference binding. The type of the
reference and the type of the temporary are not necessarily the same,
which could cause a crash. Fixes <rdar://problem/10398199>.
llvm-svn: 144646
property references to use a new PseudoObjectExpr
expression which pairs a syntactic form of the expression
with a set of semantic expressions implementing it.
This should significantly reduce the complexity required
elsewhere in the compiler to deal with these kinds of
expressions (e.g. IR generation's special l-value kind,
the static analyzer's Message abstraction), at the lower
cost of specifically dealing with the odd AST structure
of these expressions. It should also greatly simplify
efforts to implement similar language features in the
future, most notably Managed C++'s properties and indexed
properties.
Most of the effort here is in dealing with the various
clients of the AST. I've gone ahead and simplified the
ObjC rewriter's use of properties; other clients, like
IR-gen and the static analyzer, have all the old
complexity *and* all the new complexity, at least
temporarily. Many thanks to Ted for writing and advising
on the necessary changes to the static analyzer.
I've xfailed a small diagnostics regression in the static
analyzer at Ted's request.
llvm-svn: 143867
implicitly perform an lvalue-to-rvalue conversion if used on an lvalue
expression. Also improve the documentation of Expr::Evaluate* to indicate which
of them will accept expressions with side-effects.
llvm-svn: 143263
temporary objects and local variables. When detected, these split the
block, marking the new one as having only the exit block as a successor.
This prevents a large number of false positives in warnings sensitive to
no-return constructs such as -Wreturn-type, and fixes the remainder of
PR10063 along with several variations of this bug that had not been
reported. The test cases are extended across the board to cover these
patterns.
This also checks in a stress test for these types of CFGs. The stress
test declares some 32k variables, a mixture of no-return and normal
destructors. Previously, this resulted in roughly 2500 CFG blocks, but
didn't model any of the no-return destructors. With this patch, it
results in over 33k blocks, many of them now unreachable.
The nice thing about how the analyzer is set up? This causes *no*
regression in performance of building the CFG. It actually in some cases
makes it faster, as best I can benchmark. The analysis for -Wreturn-type
(and any other that cares about no-return code paths) is technically
slower now as it has to look at many more candidate blocks, but it
computes the correct answer. I have more test cases to follow, I think
they all work now. Also I have further work that should dramatically
simplify analyses in the presence of no-return.
llvm-svn: 139586
and case statements. Use this to make the logic in the CFG builder more
robust at finding the actual statements within a compound statement,
even when there are many layers of labels obscuring it.
Also extend the test cases for a large chunk of PR10063. Still more work
to do here though.
llvm-svn: 139437
incorrectly in the CFG, and also the static analyzer. This patch regresses the analyzer a bit, but
that needs to be followed up with a better solution.
Fixes <rdar://problem/10008112>.
llvm-svn: 138372
MaterializeTemporaryExpr captures a reference binding to a temporary
value, making explicit that the temporary value (a prvalue) needs to
be materialized into memory so that its address can be used. The
intended AST invariant here is that a reference will always bind to a
glvalue, and MaterializeTemporaryExpr will be used to convert prvalues
into glvalues for that binding to happen. For example, given
const int& r = 1.0;
The initializer of "r" will be a MaterializeTemporaryExpr whose
subexpression is an implicit conversion from the double literal "1.0"
to an integer value.
IR generation benefits most from this new node, since it was
previously guessing (badly) when to materialize temporaries for the
purposes of reference binding. There are likely more refactoring and
cleanups we could perform there, but the introduction of
MaterializeTemporaryExpr fixes PR9565, a case where IR generation
would effectively bind a const reference directly to a bitfield in a
struct. Addresses <rdar://problem/9552231>.
llvm-svn: 133521
Also, have Environment stop looking through NoOp casts; it didn't match the behavior of LiveVariables. And once that's gone, the whole cast block of that switch is unnecessary.
llvm-svn: 132840
This introduces a generic base class for the expression evaluator
classes, which handles a few common expression types which were
previously handled separately in each class. Also, the expression
evaluator now uses ConstStmtVisitor.
llvm-svn: 131281
1) Change the CFG to include the DeclStmt for conditional variables, instead of using the condition itself as a faux DeclStmt.
2) Update ExprEngine (the static analyzer) to understand (1), so not to regress.
3) Update UninitializedValues.cpp to initialize all tracked variables to Uninitialized at the start of the function/method.
4) Only use the SelfReferenceChecker (SemaDecl.cpp) on global variables, leaving the dataflow analysis to handle other cases.
The combination of (1) and (3) allows the dataflow-based -Wuninitialized to find self-init problems when the initializer
contained control-flow.
llvm-svn: 128858
Change the interface to expose the new information and deal with the enormous fallout.
Introduce the new ExceptionSpecificationType value EST_DynamicNone to more easily deal with empty throw specifications.
Update the tests for noexcept and fix the various bugs uncovered, such as lack of tentative parsing support.
llvm-svn: 127537
Instead, create a small set of Stmt* -> CFGBlock* mappings during CFG construction for only the statements we care about
relating to the diagnostics we want to check for reachability.
llvm-svn: 127396
Moreover, change AnalysisContext to use an OwningPtr for created analysis objects instead
of directly managing them.
Finally, add a 'forcedBlkExprs' entry to CFG::BuildOptions that will be used by the
CFGBuilder to force specific expressions to be block-level expressions.
llvm-svn: 127385
This fixes a crash reported in PR9287, and also fixes a false positive involving the value of such ternary
expressions not properly getting propagated.
llvm-svn: 126362
class and to bind the shared value using OpaqueValueExpr. This fixes an
unnoticed problem with deserialization of these expressions where the
deserialized form would lose the vital pointer-equality trait; or rather,
it fixes it because this patch also does the right thing for deserializing
OVEs.
Change OVEs to not be a "temporary object" in the sense that copy elision is
permitted.
This new representation is not totally unawkward to work with, but I think
that's really part and parcel with the semantics we're modelling here. In
particular, it's much easier to fix things like the copy elision bug and to
make the CFG look right.
I've tried to update the analyzer to deal with this in at least some
obvious cases, and I think we get a much better CFG out, but the printing
of OpaqueValueExprs probably needs some work.
llvm-svn: 125744
LabelDecl and LabelStmt. There is a 1-1 correspondence between the
two, but this simplifies a bunch of code by itself. This is because
labels are the only place where we previously had references to random
other statements, causing grief for AST serialization and other stuff.
This does cause one regression (attr(unused) doesn't silence unused
label warnings) which I'll address next.
This does fix some minor bugs:
1. "The only valid attribute " diagnostic was capitalized.
2. Various diagnostics printed as ''labelname'' instead of 'labelname'
3. This reduces duplication of label checking between functions and blocks.
Review appreciated, particularly for the cindex and template bits.
llvm-svn: 125733
implicit lvalue-to-rvalue casts that John McCall
recently introduced. This causes a whole bunch
of logic in the analyzer for handling lvalues
to vanish. It does, however, raise a few issues
in the analyzer w.r.t to modeling various constructs
(e.g., field accesses to compound literals).
The .c/.m analysis test cases that fail are
due to a missing lvalue-to-rvalue cast that
will get introduced into the AST. The .cpp
failures were more than I could investigate in
one go, and the patch was already getting huge.
I have XFAILED some of these tests, and they
should obviously be further investigated.
Some highlights of this patch include:
- CFG no longer requires an lvalue bit for
CFGElements
- StackFrameContext doesn't need an 'asLValue'
flag
- The "VisitLValue" path from GRExprEngine has
been eliminated.
Besides the test case failures (XFAILed), there
are surely other bugs that are fallout from
this change.
llvm-svn: 121960
struct X {
X() : au_i1(123) {}
union {
int au_i1;
float au_f1;
};
};
clang will now deal with au_i1 explicitly as an IndirectFieldDecl.
llvm-svn: 120900
not actually frequently used, because ImpCastExprToType only creates a node
if the types differ. So explicitly create an ICE in the lvalue-to-rvalue
conversion code in DefaultFunctionArrayLvalueConversion() as well as several
other new places, and consistently deal with the consequences throughout the
compiler.
In addition, introduce a new cast kind for loading an ObjCProperty l-value,
and make sure we emit those nodes whenever an ObjCProperty l-value appears
that's not on the LHS of an assignment operator.
This breaks a couple of rewriter tests, which I've x-failed until future
development occurs on the rewriter.
Ted Kremenek kindly contributed the analyzer workarounds in this patch.
llvm-svn: 120890
1. "no 'else' after 'return'" -- this is for conformance with the
coding standards.
2. move 'else' to the line of the previous '}' -- this is for consistency.
Reviewed by kremenek.
llvm-svn: 119983
it is possible for the confluence block to only have a single predecessor due to calls to 'noreturn'
functions. Fixes assertion failure reported in PR 8619.
llvm-svn: 119284
Elidable CXXConstructExpr should inhibit calling destructor for temporary
that is copied, not the one created. This is because eliding copy constructor
means that the object that was to be copied will be constructed directly in
memory the copy would be constructed in.
llvm-svn: 119044
1. For statement: const C& c = C(0) ?: C(1) destructors generated for condition will not differ from those generated for case without prolonged lifetime of temporary,
2. There will be no destructor for constant reference member bound to temporary at the exit from constructor.
llvm-svn: 118158
containing a DoStmt, and the LHS doesn't create a new block, then we should
return RBlock. Otherwise we'll incorrectly return NULL.
Also relax an assertion in VisitWhileStmt(). Reset 'Block' when it is finished.
llvm-svn: 117436
- Adding LocalScope for CompoundStmt,
- Adding CFGAutomaticObjDtors for end of scope, return, goto, break, continue,
- Regression tests for above cases.
llvm-svn: 115252
- post-increament, distance and bool conversion methods to LocalScope::const_iterator,
- adding VarDecl to LocalScope.
Fixed some misspells in comments.
llvm-svn: 115227
- LocalScope class with iterator used to pointing into it,
- fat doxygen comment for LocalScope indended usage,
- BlockScopePosPair class used for storing jump targets/sources (for: goto, break, continue), that replaces raw CFGBlock pointer used earlier for this purpose.
llvm-svn: 114790
- definitions of interfaces for CFGInitializer and CFGAutomaticObjDtor,
- support for above classes to print_elem function (renamed print_stmt),
- support for VarDecls in StmtPrinterHelper.
llvm-svn: 114403
to selectively walk successors/predecessors based on commonly used filters. For starters, add
a filter to ignore 'default:' cases for SwitchStmts when all enum values are covered by CaseStmts.
llvm-svn: 113449
This introduces FunctionType::ExtInfo to hold the calling convention and the
noreturn attribute. The next patch will extend it to include the regparm
attribute and fix the bug.
llvm-svn: 99920
After discussion with Zhongxing, don't force the initializer of DeclStmts to be
block-level expressions.
This led to some interesting fallout:
[UninitializedValues]
Always visit the initializer of DeclStmts (do not assume they are block-level expressions).
[BasicStore]
With initializers of DeclStmts no longer block-level expressions, this causes self-referencing initializers (e.g. 'int x = x') to no longer cause the initialized variable to be live before the DeclStmt. While this is correct, it caused BasicStore::RemoveDeadBindings() to prune off the values of these variables from the initial store (where they are set to uninitialized). The fix is to back-port some (and only some) of the lazy-binding logic from RegionStore to
BasicStore. Now the default values of local variables are determined lazily as opposed
to explicitly initialized.
llvm-svn: 97591
CallExprs as those edges help cause a n^2 explosion in the number of
destructor calls. Other consumers, such as static analysis, that
would like to have more a more complete CFG can select the inclusion
of those edges as CFG build time.
This also fixes up the two compilation users of CFGs to be tolerant of
having or not having those edges. All catch code is assumed be to
live if we didn't generate the exceptional edges for CallExprs.
llvm-svn: 94074