Commit Graph

644 Commits

Author SHA1 Message Date
Alexander Kornienko ab9db51042 Revert r240270 ("Fixed/added namespace ending comments using clang-tidy").
llvm-svn: 240353
2015-06-22 23:07:51 +00:00
Alexander Kornienko 3d9d929e42 Fixed/added namespace ending comments using clang-tidy. NFC
The patch is generated using this command:

  $ tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \
      -checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \
      work/llvm/tools/clang

To reduce churn, not touching namespaces spanning less than 10 lines.

llvm-svn: 240270
2015-06-22 09:47:44 +00:00
Yunzhong Gao cb77930d6b Implementing C99 partial re-initialization behavior (DR-253)
Based on previous discussion on the mailing list, clang currently lacks support
for C99 partial re-initialization behavior:
Reference: http://lists.cs.uiuc.edu/pipermail/cfe-dev/2013-April/029188.html
Reference: http://www.open-std.org/jtc1/sc22/wg14/www/docs/dr_253.htm

This patch attempts to fix this problem.

Given the following code snippet,

struct P1 { char x[6]; };
struct LP1 { struct P1 p1; };

struct LP1 l = { .p1 = { "foo" }, .p1.x[2] = 'x' };
// this example is adapted from the example for "struct fred x[]" in DR-253;
// currently clang produces in l: { "\0\0x" },
//   whereas gcc 4.8 produces { "fox" };
// with this fix, clang will also produce: { "fox" };


Differential Review: http://reviews.llvm.org/D5789

llvm-svn: 239446
2015-06-10 00:27:52 +00:00
Jonathan Roelofs 104cbf9c32 Fix PR21945: Crash in constant evaluator.
Patch by Косов Евгений!

llvm-svn: 238758
2015-06-01 16:23:08 +00:00
Richard Smith 419bd09415 PR23373: A defaulted union copy constructor that is not trivial must still be
emitted as a memcpy.

llvm-svn: 236142
2015-04-29 19:26:57 +00:00
Benjamin Kramer 8407df72a3 Make helper functions static. NFC.
Found by -Wmissing-prototypes.

llvm-svn: 231668
2015-03-09 16:47:52 +00:00
Petar Jovanovic d55ae6ba37 Add support for generating MIPS legacy NaN
Currently, the NaN values emitted for MIPS architectures do not cover
non-IEEE754-2008 compliant case. This change fixes the issue.

Patch by Vladimir Radosavljevic.

Differential Revision: http://reviews.llvm.org/D7882

llvm-svn: 230653
2015-02-26 18:19:22 +00:00
Aaron Ballman 673476684e Removing LLVM_EXPLICIT, as MSVC 2012 was the last reason for requiring the macro. NFC; Clang edition.
llvm-svn: 229336
2015-02-15 22:00:28 +00:00
Josh Magee 4d1a79b8c0 Catch more cases when diagnosing integer-constant-expression overflows.
When visiting AssignmentOps, keep evaluating after a failure (when possible) in
order to identify overflow in subexpressions.

Differential Revision: http://reviews.llvm.org/D1238

llvm-svn: 228202
2015-02-04 21:50:20 +00:00
Richard Smith 513955c487 Support constant evaluation for member calls on std::initializer_list
temporaries.

llvm-svn: 224449
2014-12-17 19:24:30 +00:00
Nick Lewycky f0202ca775 Improve handling of value dependent expressions in __attribute__((enable_if)), both in the condition expression and at the call site. Fixes PR20988!
llvm-svn: 224320
2014-12-16 06:12:01 +00:00
David Majnemer 8c92b87cd0 AST: Limit zero-sized constexpr behavior to array types
Restricting this "extension" to array types maximizes our standards
conformance while not miscompiling real-world programs.

llvm-svn: 224215
2014-12-14 08:40:47 +00:00
David Majnemer 27db35878d AST: Incomplete types might be zero sized
Comparing the address of an object with an incomplete type might return
true with a 'distinct' object if the former has a size of zero.
However, such an object should compare unequal with null.

llvm-svn: 224040
2014-12-11 19:36:24 +00:00
David Majnemer b511603281 AST: Don't assume two zero sized objects live at different addresses
Zero sized objects may overlap with each other or any other object.

This fixes PR21786.

llvm-svn: 223852
2014-12-09 23:32:34 +00:00
Anastasia Stulova 5d8ad8a7b8 [OpenCL] Implemented restrictions for pointer conversions specified in OpenCL v2.0.
OpenCL v2.0 s6.5.5 restricts conversion of pointers to different address spaces:
- the named address spaces (__global, __local, and __private) => __generic - implicitly converted;
- __generic => named - with an explicit cast;
- named <=> named - disallowed;
- __constant <=> any other - disallowed.

llvm-svn: 222834
2014-11-26 15:36:41 +00:00
Richard Smith be6dd818fb Fix bug where a trivial constexpr copy/move operation couldn't copy from an
empty non-constexpr object. Such a copy doesn't break any of the constexpr
rules.

llvm-svn: 222387
2014-11-19 21:27:17 +00:00
Richard Smith 98710fc4f5 Fix assert/crash on invalid with __builtin_constant_p conditionals in constant expressions.
llvm-svn: 221942
2014-11-13 23:03:19 +00:00
Richard Smith 0f0af19b05 [c++1z] N4295: fold-expressions.
This is a new form of expression of the form:

  (expr op ... op expr)

where one of the exprs is a parameter pack. It expands into

  (expr1 op (expr2onwards op ... op expr))

(and likewise if the pack is on the right). The non-pack operand can be
omitted; in that case, an empty pack gives a fallback value or an error,
depending on the operator.

llvm-svn: 221573
2014-11-08 05:07:16 +00:00
Kaelyn Takata e1f49d545d Add the initial TypoExpr AST node for delayed typo correction.
llvm-svn: 220692
2014-10-27 18:07:20 +00:00
Richard Smith d20f1e6dd3 PR21327 / C++ DR1652 / C++ DR73: comparing a past-the-end pointer for one
complete object to a pointer to the start of another complete object does
not evaluate to the constant 'false'. All other comparisons between the
addresses of subobjects of distinct complete objects still do.

llvm-svn: 220343
2014-10-21 23:01:04 +00:00
Chandler Carruth b29a743891 [complex] Teach the other two binary operators on complex numbers (==
and !=) to support mixed complex and real operand types.

This requires removing an assert from SemaChecking, and adding support
both to the constant evaluator and the code generator to synthesize the
imaginary part when needed. This seemed somewhat cleaner than having
just the comparison operators force real-to-complex conversions.

I've added test cases for these operations. I'm really terrified that
there were *no* tests in-tree which exercised this.

This turned up when trying to build R after my change to the complex
type lowering.

llvm-svn: 219570
2014-10-11 11:03:30 +00:00
Chandler Carruth a216cad0fc [complex] Teach Clang to preserve different-type operands to arithmetic
operators where one type is a C complex type, and to emit both the
efficient and correct implementation for complex arithmetic according to
C11 Annex G using this extra information.

For both multiply and divide the old code was writing a long-hand
reduced version of the math without any of the special handling of inf
and NaN recommended by the standard here. Instead of putting more
complexity here, this change does what GCC does which is to emit
a libcall for the fully general case.

However, the old code also failed to do the proper minimization of the
set of operations when there was a mixed complex and real operation. In
those cases, C provides a spec for much more minimal operations that are
valid. Clang now emits the exact suggested operations. This change isn't
*just* about performance though, without minimizing these operations, we
again lose the correct handling of infinities and NaNs. It is critical
that this happen in the frontend based on assymetric type operands to
complex math operations.

The performance implications of this change aren't trivial either. I've
run a set of benchmarks in Eigen, an open source mathematics library
that makes heavy use of complex. While a few have slowed down due to the
libcall being introduce, most sped up and some by a huge amount: up to
100% and 140%.

In order to make all of this work, also match the algorithm in the
constant evaluator to the one in the runtime library. Currently it is
a broken port of the simplifications from C's Annex G to the long-hand
formulation of the algorithm.

Splitting this patch up is very hard because none of this works without
the AST change to preserve non-complex operands. Sorry for the enormous
change.

Follow-up changes will include support for sinking the libcalls onto
cold paths in common cases and fastmath improvements to allow more
aggressive backend folding.

Differential Revision: http://reviews.llvm.org/D5698

llvm-svn: 219557
2014-10-11 00:57:18 +00:00
Alexey Bataev ec4747802a Fix for bug http://llvm.org/PR17427.
Assertion failed: "Computed __func__ length differs from type!"
Reworked PredefinedExpr representation with internal StringLiteral field for function declaration.
Differential Revision: http://reviews.llvm.org/D5365

llvm-svn: 219393
2014-10-09 08:45:04 +00:00
Hal Finkel 0dd05d4b59 constexpr evaluation for __builtin_assume_aligned
Richard noted in the review of r217349 that extra handling of
__builtin_assume_aligned inside of the expression evaluator was needed. He was
right, and this should address the concerns raised, namely:

 1. The offset argument to __builtin_assume_aligned can have side effects, and
    we need to make sure that all arguments are properly evaluated.

 2. If the alignment assumption does not hold, that introduces undefined
    behavior, and undefined behavior cannot appear inside a constexpr.

and hopefully the diagnostics produced are detailed enough to explain what is
going on.

llvm-svn: 218992
2014-10-03 17:18:37 +00:00
Hal Finkel 92b9b49f61 Revert useless part of r217349
Adding handling of __builtin_assume_aligned to IntExprEvaluator does not make
sense because __builtin_assume_aligned returns a pointer (not an integer).
Thanks to Richard for figuring out why this was not doing anything.

I'll add this back in a better place (PointerExprEvaluator perhaps).

llvm-svn: 218958
2014-10-03 04:46:46 +00:00
Fariborz Jahanian a3d8879be7 Fix evatuated value of __builtin_object_size according to its
'type'  argument when it cannot be determined which objects ptr 
points to at compile time. rdar://18334276

llvm-svn: 218258
2014-09-22 17:11:59 +00:00
Richard Smith b01fe40c07 Reject a slightly-sneaky way to perform a read of mutable state from within a
constexpr function. Part of this fix is a tentative fix for an as-yet-unfiled
core issue (we're missing a prohibition against reading mutable members from
unions via a trivial constructor/assignment, since that doesn't perform an
lvalue-to-rvalue conversion on the members).

llvm-svn: 217852
2014-09-16 01:24:02 +00:00
Hal Finkel bcc06085a8 Add __builtin_assume and __builtin_assume_aligned using @llvm.assume.
This makes use of the recently-added @llvm.assume intrinsic to implement a
__builtin_assume(bool) intrinsic (to provide additional information to the
optimizer). This hooks up __assume in MS-compatibility mode to mirror
__builtin_assume (the semantics have been intentionally kept compatible), and
implements GCC's __builtin_assume_aligned as assume((p - o) & mask == 0). LLVM
now contains special logic to deal with assumptions of this form.

llvm-svn: 217349
2014-09-07 22:58:14 +00:00
Craig Topper 5fc8fc2d31 Simplify creation of a bunch of ArrayRefs by using None, makeArrayRef or just letting them be implicitly created.
llvm-svn: 216528
2014-08-27 06:28:36 +00:00
Aaron Ballman dd69ef38db C++1y is now C++14!
Changes diagnostic options, language standard options, diagnostic identifiers, diagnostic wording to use c++14 instead of c++1y. It also modifies related test cases to use the updated diagnostic wording.

llvm-svn: 215982
2014-08-19 15:55:55 +00:00
Richard Smith 77be48ac47 PR18097: Support initializing an _Atomic(T) from an object of C++ class type T
or a class derived from T. We already supported this when initializing
_Atomic(T) from T for most (and maybe all) other reasonable values of T.

llvm-svn: 214390
2014-07-31 06:31:19 +00:00
Richard Smith 33b44ab2b7 Replace r213816's fix with a different one. It's not meaningful to call
isOnePastTheEnd on an invalid designator, so assert and push the check into the
one caller that wasn't already checking.

llvm-svn: 213820
2014-07-23 23:50:25 +00:00
Reid Kleckner 142dd46c2a Add a missing Invalid check to SubobjectDesignator::isOnePastEnd()
The class seems to have an invariant that Entries is non-empty if
Invalid is false.  It appears this method was previously private, and
all internal uses checked Invalid.  Now there is an external caller, so
check Invalid to avoid array OOB underflow.

Fixes PR20420.

llvm-svn: 213816
2014-07-23 23:24:25 +00:00
Hal Finkel a8443c36ae Handle __assume in the VoidExprEvaluator
This is a follow-up to an IRC conversation with Richard last night; __assume
does not evaluate its argument, and so the argument should not contribute to
whether (__assume(e), constant) can be used where a constant is required.

llvm-svn: 213267
2014-07-17 14:49:58 +00:00
Anders Carlsson 1a9fe3d4db Handle __builtin_clzs and __builtin_ctzs in the constant expression evaluator.
llvm-svn: 212464
2014-07-07 15:53:44 +00:00
Richard Smith 22a5d61b5d Add an explicit diagnostic for the case where an expression is not a constant
expression because it uses 'this'. Inspired by PR20219 comment#2.

llvm-svn: 212433
2014-07-07 06:00:13 +00:00
Craig Topper 00bbdcf9b3 Remove llvm:: from uses of ArrayRef.
llvm-svn: 211987
2014-06-28 23:22:23 +00:00
Hans Wennborg 82dd877e8a Don't allow dllimport variables in constant initializers
This is a follow-up to David's r211677. For the following code,
we would end up referring to 'foo' in the initializer for 'arr',
and then fail to link, because 'foo' is dllimport and needs to be
accessed through the __imp_?foo.

  __declspec(dllimport) extern const char foo[];
  const char* f() {
    static const char* const arr[] = { foo };
    return arr[0];
  }

Differential Revision: http://reviews.llvm.org/D4299

llvm-svn: 211736
2014-06-25 22:19:48 +00:00
David Majnemer 0c43d8077e AST: Initialization with dllimport functions in C
The C++ language requires that the address of a function be the same
across all translation units.  To make __declspec(dllimport) useful,
this means that a dllimported function must also obey this rule.  MSVC
implements this by dynamically querying the import address table located
in the linked executable.  This means that the address of such a
function in C++ is not constant (which violates other rules).

However, the C language has no notion of ODR nor does it permit dynamic
initialization whatsoever.  This requires implementations to _not_
dynamically query the import address table and instead utilize a wrapper
function that will be synthesized by the linker which will eventually
query the import address table.  The effect this has is, to say the
least, perplexing.

Consider the following C program:
__declspec(dllimport) void f(void);

typedef void (*fp)(void);

static const fp var = &f;

const fp fun() { return &f; }

int main() { return fun() == var; }

MSVC will statically initialize "var" with the address of the wrapper
function and "fun" returns the address of the actual imported function.
This means that "main" will return false!

Note that LLVM's optimizers are strong enough to figure out that "main"
should return true.  However, this result is dependent on having
optimizations enabled!

N.B.  This change also permits the usage of dllimport declarators inside
of template arguments; they are sufficiently constant for such a
purpose.  Add tests to make sure we don't regress here.

llvm-svn: 211677
2014-06-25 08:15:07 +00:00
David Majnemer 11a54c3465 AST: Address of dllimport functions isn't constant
The address of dllimport functions can be accessed one of two ways:
- Through the IAT which is symbolically referred to with a symbol
  starting with __imp_.
- Via the wrapper-function which ends up calling through the __imp_
  symbol.

The problem with using the wrapper-function is that it's address will
not compare as equal in all translation units.  Specifically, it will
compare unequally with the translation unit which defines the function.

This fixes PR19955.

llvm-svn: 211570
2014-06-24 06:40:51 +00:00
David Majnemer c28a964cba AST: Address of dllimport variables isn't constant
The address of dllimport variables isn't something that can be
meaningfully used in a constexpr context and isn't suitable for
evaluation at load-time.  They require loads from memory to properly
evaluate.

This fixes PR19955.

Differential Revision: http://reviews.llvm.org/D4250

llvm-svn: 211568
2014-06-24 05:59:13 +00:00
Richard Smith 3e79a57a6d Add missing "non-constant" diagnostic for a member call on a temporary of
non-literal class type.

llvm-svn: 210696
2014-06-11 19:53:12 +00:00
Richard Smith f6d7030f0f Related to PR19992: when the GNU alignof-expression extension is applied to an
expression of array-of-unknown-bound type, don't try to complete the array
bound, and return the alignment of the element type rather than 1.

llvm-svn: 210608
2014-06-10 23:34:28 +00:00
Craig Topper 36250ad632 [C++11] Use 'nullptr'. AST edition.
llvm-svn: 208517
2014-05-12 05:36:57 +00:00
Richard Smith 6c6bbfab19 PR19346: Adding 0 to a null pointer has defined behavior in C++. Allow it in constant expressions.
llvm-svn: 205757
2014-04-08 12:19:28 +00:00
Aaron Ballman c7e4e219b5 [C++11] Replacing CompoundStmt iterators body_begin() and body_end() with iterator_range body(). Updating all of the usages of the iterators with range-based for loops.
llvm-svn: 204040
2014-03-17 14:19:37 +00:00
James Dennett 0492ef0e0b Fix a crash (assertion failure) in EvaluateAsRValue.
Summary:
Gracefully fail to evaluate a constant expression if its type is
unknown, rather than failing an assertion trying to access the type.

Reviewers: klimek

Reviewed By: klimek

CC: chandlerc, cfe-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D3075

llvm-svn: 203950
2014-03-14 17:44:10 +00:00
Aaron Ballman 535bbcccb1 [C++11] Replacing DeclStmt iterators decl_begin() and decl_end() with iterator_range decls(). Updating all of the usages of the iterators with range-based for loops.
llvm-svn: 203947
2014-03-14 17:01:24 +00:00
Aaron Ballman 0ad78303de [C++11] Replacing CXXRecordDecl iterators init_begin() and init_end() with iterator_range inits(). Updating all of the usages of the iterators with range-based for loops.
llvm-svn: 203819
2014-03-13 17:34:31 +00:00
Aaron Ballman 62e47c423d Reverting llvm::distance changes to use std::distance with iterators instead, per post-commit review feedback.
Replacing llvm::copy changes with SmallVector range-based construction which is a considerably cleaner approach.

llvm-svn: 203461
2014-03-10 13:43:55 +00:00