Syntax:
asm [volatile] goto ( AssemblerTemplate
:
: InputOperands
: Clobbers
: GotoLabels)
https://gcc.gnu.org/onlinedocs/gcc/Extended-Asm.html
New llvm IR is "callbr" for inline asm goto instead "call" for inline asm
For:
asm goto("testl %0, %0; jne %l1;" :: "r"(cond)::label_true, loop);
IR:
callbr void asm sideeffect "testl $0, $0; jne ${1:l};", "r,X,X,~{dirflag},~{fpsr},~{flags}"(i32 %0, i8* blockaddress(@foo, %label_true), i8* blockaddress(@foo, %loop)) #1
to label %asm.fallthrough [label %label_true, label %loop], !srcloc !3
asm.fallthrough:
Compiler need to generate:
1> a dummy constarint 'X' for each label.
2> an unique fallthrough label for each asm goto stmt " asm.fallthrough%number".
Diagnostic
1> duplicate asm operand name are used in output, input and label.
2> goto out of scope.
llvm-svn: 362045
Summary:
The following changes were required to fix these tests:
1) Change LLVM_ENABLE_PLUGINS to an option and move it to
llvm/CMakeLists.txt with an appropriate default -- which matches
the original default behavior.
2) Move the plugins directory from clang/test/Analysis
clang/lib/Analysis. It's not enough to add an exclude to the
lit.local.cfg file because add_lit_testsuites recurses the tree and
automatically adds the appropriate `check-` targets, which don't
make sense for the plugins because they aren't tests and don't
have `RUN` statements.
Here's a list of the `clang-check-anlysis*` targets with this
change:
```
$ ninja -t targets all| sed -n "s/.*\/\(check[^:]*\):.*/\1/p" | sort -u | grep clang-analysis
check-clang-analysis
check-clang-analysis-checkers
check-clang-analysis-copypaste
check-clang-analysis-diagnostics
check-clang-analysis-engine
check-clang-analysis-exploration_order
check-clang-analysis-html_diagnostics
check-clang-analysis-html_diagnostics-relevant_lines
check-clang-analysis-inlining
check-clang-analysis-objc
check-clang-analysis-unified-sources
check-clang-analysis-z3
```
3) Simplify the logic and only include the subdirectories under
clang/lib/Analysis/plugins if LLVM_ENABLE_PLUGINS is set.
Reviewed By: NoQ
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D62445
llvm-svn: 361790
This patch adds the run-time CFG branch that would skip initialization of
virtual base classes depending on whether the constructor is called from a
superclass constructor or not. Previously the Static Analyzer was already
skipping virtual base-class initializers in such constructors, but it wasn't
skipping their arguments and their potential side effects, which was causing
pr41300 (and was generally incorrect). The previous skipping behavior is
now replaced with a hard assertion that we're not even getting there due
to how our CFG works.
The new CFG element is under a CFG build option so that not to break other
consumers of the CFG by this change. Static Analyzer support for this change
is implemented.
Differential Revision: https://reviews.llvm.org/D61816
llvm-svn: 361681
Turn it into a variant class instead. This conversion does indeed save some code
but there's a plan to add support for more kinds of terminators that aren't
necessarily based on statements, and with those in mind it becomes more and more
confusing to have CFGTerminators implicitly convertible to a Stmt *.
Differential Revision: https://reviews.llvm.org/D61814
llvm-svn: 361586
new expression.
This was voted into C++20 as a defect report resolution, so we
retroactively apply it to all prior language modes (though it can never
actually be used before C++11 mode).
llvm-svn: 360006
Currently we always inline functions that have no branches, i.e. have exactly
three CFG blocks: ENTRY, some code, EXIT. This makes sense because when there
are no branches, it means that there's no exponential complexity introduced
by inlining such function. Such functions also don't trigger various fundamental
problems with our inlining mechanism, such as the problem of inlined
defensive checks.
Sometimes the CFG may contain more blocks, but in practice it still has
linear structure because all directions (except, at most, one) of all branches
turned out to be unreachable. When this happens, still treat the function
as "small". This is useful, in particular, for dealing with C++17 if constexpr.
Differential Revision: https://reviews.llvm.org/D61051
llvm-svn: 359531
In the OSObject universe there appears to be another slightly popular contract,
apart from "create" and "get", which is "matching". It optionally consumes
a "table" parameter and if a table is passed, it fills in the table and
returns it at +0; otherwise, it creates a new table, fills it in and
returns it at +1.
For now suppress false positives by doing a conservative escape on all functions
that end with "Matching", which is the naming convention that seems to be
followed by all such methods.
Differential Revision: https://reviews.llvm.org/D61161
llvm-svn: 359264
When growing a body on a body farm, it's essential to use the same redeclaration
of the function that's going to be used during analysis. Otherwise our
ParmVarDecls won't match the ones that are used to identify argument regions.
This boils down to trusting the reasoning in AnalysisDeclContext. We shouldn't
canonicalize the declaration before farming the body because it makes us not
obey the sophisticated decision-making process of AnalysisDeclContext.
Differential Revision: https://reviews.llvm.org/D60899
llvm-svn: 358946
Summary:
SExprBuilder::translateDeclRefExpr was only looking at FunctionDecl and not also looking at ObjCMethodDecl. It should consider both because the attributes can be used on Objective-C as well.
<rdar://problem/48941331>
Reviewers: dexonsmith, erik.pilkington
Subscribers: jkorous, jdoerfert, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D59523
llvm-svn: 356940
When searching for construction contexts, i.e. figuring out which statements
define the object that is constructed by each construct-expression, ignore
transparent init-list expressions because they don't add anything to the
context. This allows the Static Analyzer to model construction, destruction,
materialization, lifetime extension correctly in more cases. Also fixes
a crash caused by incorrectly evaluating initial values of variables
initialized with such expressions.
Differential Revision: https://reviews.llvm.org/D59573
llvm-svn: 356634
Summary:
Similar to D56967, we add the existing diag::note_locked_here to tell
the user where we saw the locking that isn't matched correctly.
Reviewers: aaron.ballman, delesley
Reviewed By: aaron.ballman
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D59455
llvm-svn: 356427
Don't crash when a function has a name that starts with "CF" and ends with
"Retain" but takes 0 arguments. In particular, don't try to treat it as if
it returns its first argument.
These problems are inevitable because the checker is naming-convention-based,
but at least we shouldn't crash.
Differential Revision: https://reviews.llvm.org/D59123
llvm-svn: 356223
We should track mutation of a variable within a comma operator expression.
Current code in ExprMutationAnalyzer does not handle it.
This will handle cases like:
(a, b) ++ < == b is modified
(a, b) = c < == b is modifed
Patch by Djordje Todorovic.
Differential Revision: https://reviews.llvm.org/D58894
llvm-svn: 355605
Summary:
The idea is that the code here isn't written, so doesn't indicate a bug.
Similar to code expanded from macros.
This means the warning no longer fires on this code:
for (auto C : collection) {
process(C);
return;
}
handleEmptyCollection();
Unclear whether this is more often a bug or not in practice, I think it's a
reasonable idiom in some cases.
Either way, if we want to warn on "loop that doesn't loop", I think it should be
a separate warning, and catch `while(1) break;`
Reviewers: ilya-biryukov, ioeric
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D58134
llvm-svn: 354102
The description of what the various Expr::Ignore* do has drifted from the
actual implementation.
Inspection reveals that IgnoreParenImpCasts() is not equivalent to doing
IgnoreParens() + IgnoreImpCasts() until reaching a fixed point, but
IgnoreParenCasts() is equivalent to doing IgnoreParens() + IgnoreCasts()
until reaching a fixed point. There is also a fair amount of duplication
in the various Expr::Ignore* functions which increase the chance of further
future inconsistencies. In preparation for the next patch which will factor
out the implementation of the various Expr::Ignore*, do the following cleanups:
Remove Stmt::IgnoreImplicit, in favor of Expr::IgnoreImplicit. IgnoreImplicit
is the only function among all of the Expr::Ignore* which is available in Stmt.
There are only a few users of Stmt::IgnoreImplicit. They can just use instead
Expr::IgnoreImplicit like they have to do for the other Ignore*.
Move Expr::IgnoreImpCasts() from Expr.h to Expr.cpp. This made no difference
in the run-time with my usual benchmark (-fsyntax-only on all of Boost).
While we are at it, make IgnoreParenNoopCasts take a const reference to the
ASTContext for const correctness.
Update the comments to match what the Expr::Ignore* are actually doing.
I am not sure that listing exactly what each Expr::Ignore* do is optimal,
but it certainly looks better than the current state which is in my opinion
between misleading and just plain wrong.
The whole patch is NFC (if you count removing Stmt::IgnoreImplicit as NFC).
Differential Revision: https://reviews.llvm.org/D57266
Reviewed By: aaron.ballman
llvm-svn: 353006
This builtin has the same UI as __builtin_object_size, but has the
potential to be evaluated dynamically. It is meant to be used as a
drop-in replacement for libraries that use __builtin_object_size when
a dynamic checking mode is enabled. For instance,
__builtin_object_size fails to provide any extra checking in the
following function:
void f(size_t alloc) {
char* p = malloc(alloc);
strcpy(p, "foobar"); // expands to __builtin___strcpy_chk(p, "foobar", __builtin_object_size(p, 0))
}
This is an overflow if alloc < 7, but because LLVM can't fold the
object size intrinsic statically, it folds __builtin_object_size to
-1. With __builtin_dynamic_object_size, alloc is passed through to
__builtin___strcpy_chk.
rdar://32212419
Differential revision: https://reviews.llvm.org/D56760
llvm-svn: 352665
Summary:
We use the existing diag::note_locked_here to tell the user where we saw
the first locking.
Reviewers: aaron.ballman, delesley
Reviewed By: aaron.ballman
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D56967
llvm-svn: 352549
Track them for ISL/OS objects by default, and for NS/CF under a flag.
rdar://47536377
Differential Revision: https://reviews.llvm.org/D57356
llvm-svn: 352534
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
If a property is defined with a custom getter, we should not behave as if
the getter simply returns an instance variable. We don't support setters,
so they aren't affected.
On top of being the right thing to do, this also fixes a crash on
the newly added test - in which a property and its getter are defined
in two separate categories.
rdar://problem/47051544
Differential Revision: https://reviews.llvm.org/D56823
llvm-svn: 351609
Summary:
https://reviews.llvm.org/D54862 removed the usages of `ASTContext&` from
within the `CXXMethodDecl::getThisType` method. Remove the parameter
altogether, as well as all usages of it. This does not result in any
functional change because the parameter was unused since
https://reviews.llvm.org/D54862.
Test Plan: check-clang
Reviewers: akyrtzi, mikael
Reviewed By: mikael
Subscribers: mehdi_amini, dexonsmith, cfe-commits
Differential Revision: https://reviews.llvm.org/D56509
llvm-svn: 350914
Since CallExpr::setNumArgs has been removed, it is now possible to store the
callee expression and the argument expressions of CallExpr in a trailing array.
This saves one pointer per CallExpr, CXXOperatorCallExpr, CXXMemberCallExpr,
CUDAKernelCallExpr and UserDefinedLiteral.
Given that CallExpr is used as a base of the above classes we cannot use
llvm::TrailingObjects. Instead we store the offset in bytes from the this pointer
to the start of the trailing objects and manually do the casts + arithmetic.
Some notes:
1.) I did not try to fit the number of arguments in the bit-fields of Stmt.
This leaves some space for future additions and avoid the discussion about
whether x bits are sufficient to hold the number of arguments.
2.) It would be perfectly possible to recompute the offset to the trailing
objects before accessing the trailing objects. However the trailing objects
are frequently accessed and benchmarks show that it is slightly faster to
just load the offset from the bit-fields. Additionally, because of 1),
we have plenty of space in the bit-fields of Stmt.
Differential Revision: https://reviews.llvm.org/D55771
Reviewed By: rjmccall
llvm-svn: 349910
All of the other constructors already take a reference to the AST context.
This avoids calling Decl::getASTContext in most cases. Additionally move
the definition of the constructor from Expr.h to Expr.cpp since it is calling
DeclRefExpr::computeDependence. NFC.
llvm-svn: 349901
StaticAnalyzer uses the CFG-based RelaxedLiveVariables analysis in order to,
in particular, figure out values of which expressions are still needed.
When the expression becomes "dead", it is garbage-collected during
the dead binding scan.
Expressions that constitute branches/bodies of control flow statements,
eg. `E1' in `if (C1) E1;' but not `E2' in `if (C2) { E2; }', were kept alive
for too long. This caused false positives in MoveChecker because it relies
on cleaning up loop-local variables when they go out of scope, but some of those
live-for-too-long expressions were keeping a reference to those variables.
Fix liveness analysis to correctly mark these expressions as dead.
Add a debug checker, debug.DumpLiveStmts, in order to test expressions liveness.
Differential Revision: https://reviews.llvm.org/D55566
llvm-svn: 349320
Summary:
The pattern is problematic with C++ exceptions, and not as widespread as
scoped locks, but it's still used by some, for example Chromium.
We are a bit stricter here at join points, patterns that are allowed for
scoped locks aren't allowed here. That could still be changed in the
future, but I'd argue we should only relax this if people ask for it.
Fixes PR36162.
Reviewers: aaron.ballman, delesley, pwnall
Reviewed By: delesley, pwnall
Subscribers: pwnall, cfe-commits
Differential Revision: https://reviews.llvm.org/D52578
llvm-svn: 349300
CallGraph previously would just show the normal name of a function,
which gets really confusing when using it on large C++ projects. This
patch switches the printName call to a printQualifiedName, so that the
namespaces are included.
Change-Id: Ie086d863f6b2251be92109ea1b0946825b28b49a
llvm-svn: 348950
It seems the two failing tests can be simply fixed after r348037
Fix 3 cases in Analysis/builtin-functions.cpp
Delete the bad CodeGen/builtin-constant-p.c for now
llvm-svn: 348053
Kept the "indirect_builtin_constant_p" test case in test/SemaCXX/constant-expression-cxx1y.cpp
while we are investigating why the following snippet fails:
extern char extern_var;
struct { int a; } a = {__builtin_constant_p(extern_var)};
llvm-svn: 348039
This was reverted in r347656 due to me thinking it caused a miscompile of
Chromium. Turns out it was the Chromium code that was broken.
llvm-svn: 347756
This caused a miscompile in Chrome (see crbug.com/908372) that's
illustrated by this small reduction:
static bool f(int *a, int *b) {
return !__builtin_constant_p(b - a) || (!(b - a));
}
int arr[] = {1,2,3};
bool g() {
return f(arr, arr + 3);
}
$ clang -O2 -S -emit-llvm a.cc -o -
g() should return true, but after r347417 it became false for some reason.
This also reverts the follow-up commits.
r347417:
> Re-Reinstate 347294 with a fix for the failures.
>
> Don't try to emit a scalar expression for a non-scalar argument to
> __builtin_constant_p().
>
> Third time's a charm!
r347446:
> The result of is.constant() is unsigned.
r347480:
> A __builtin_constant_p() returns 0 with a function type.
r347512:
> isEvaluatable() implies a constant context.
>
> Assume that we're in a constant context if we're asking if the expression can
> be compiled into a constant initializer. This fixes the issue where a
> __builtin_constant_p() in a compound literal was diagnosed as not being
> constant, even though it's always possible to convert the builtin into a
> constant.
r347531:
> A "constexpr" is evaluated in a constant context. Make sure this is reflected
> if a __builtin_constant_p() is a part of a constexpr.
llvm-svn: 347656