Commit Graph

258 Commits

Author SHA1 Message Date
Xiuli Pan 97f9428a0d [OpenCL] Pipe type support
Summary:
Support for OpenCL 2.0 pipe type.
This is a bug-fix version for bader's patch reviews.llvm.org/D14441


Reviewers: pekka.jaaskelainen, Anastasia

Subscribers: bader, Anastasia, cfe-commits

Differential Revision: http://reviews.llvm.org/D15603

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@257254 91177308-0d34-0410-b5e6-96231b3b80d8
2016-01-09 12:53:17 +00:00
Benjamin Kramer 9f3e8630d7 Replace llvm::utostr calls in Twine context with Twines. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@256377 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-24 10:07:37 +00:00
James Y Knight ba55d246b9 [TrailingObjects] Convert ASTTemplateKWAndArgsInfo and ASTTemplateArgumentListInfo.
Doing so required separating them so that the former doesn't inherit
from the latter anymore. Investigating that, it became clear that the
inheritance wasn't actually providing real value in any case.

So also:
- Remove a bunch of redundant functions (getExplicitTemplateArgs,
  getOptionalExplicitTemplateArgs) on various Expr subclasses which
  depended on the inheritance relationship.
- Switched external callers to use pre-existing accessors that return the
  data they're actually interested in (getTemplateArgs,
  getNumTemplateArgs, etc).
- Switched internal callers to use pre-existing getTemplateKWAndArgsInfo.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@256359 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-24 02:59:37 +00:00
George Burgess IV 7727f3dca1 Add the `pass_object_size` attribute to clang.
`pass_object_size` is our way of enabling `__builtin_object_size` to
produce high quality results without requiring inlining to happen
everywhere.

A link to the design doc for this attribute is available at the
Differential review link below.

Differential Revision: http://reviews.llvm.org/D13263


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@254554 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-02 21:58:08 +00:00
Alexey Bataev 0a368f60e7 [MSVC] 'property' with an empty array in array subscript expression.
MSVC supports 'property' attribute and allows to apply it to the declaration of an empty array in a class or structure definition.
For example:
```
__declspec(property(get=GetX, put=PutX)) int x[];
```
The above statement indicates that x[] can be used with one or more array indices. In this case, i=p->x[a][b] will be turned into i=p->GetX(a, b), and p->x[a][b] = i will be turned into p->PutX(a, b, i);
Differential Revision: http://reviews.llvm.org/D13336


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@254067 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-25 12:01:00 +00:00
Richard Smith ea21696b87 Add support for GCC's '__auto_type' extension, per the GCC manual:
https://gcc.gnu.org/onlinedocs/gcc/Typeof.html

Differences from the GCC extension:
 * __auto_type is also permitted in C++ (but only in places where
   it could appear in C), allowing its use in headers that might
   be shared across C and C++, or used from C++98
 * __auto_type can be combined with a declarator, as with C++ auto
   (for instance, "__auto_type *p")
 * multiple variables can be declared in a single __auto_type
   declaration, with the C++ semantics (the deduced type must be
   the same in each case)

This patch also adds a missing restriction on applying typeof to
a bit-field, which GCC has historically rejected in C (due to
lack of clarity as to whether the operand should be promoted).
The same restriction also applies to __auto_type in C (in both
GCC and Clang).

This also fixes PR25449.

Patch by Nicholas Allegra!


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@252690 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-11 02:02:15 +00:00
Richard Smith 708f13bd1a [coroutines] Creation of promise object, lookup of operator co_await, building
of await_* calls, and AST representation for same.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@251387 91177308-0d34-0410-b5e6-96231b3b80d8
2015-10-27 06:02:45 +00:00
Richard Smith 79ba8b3864 [coroutines] Add overloaded unary 'operator co_await'.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@250991 91177308-0d34-0410-b5e6-96231b3b80d8
2015-10-22 05:12:22 +00:00
Richard Smith 1878f91a0a PR14858: Initial support for proper sizeof... handling within alias templates.
This doesn't quite get alias template equivalence right yet, but handles the
egregious cases where we would silently give the wrong answers.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@248431 91177308-0d34-0410-b5e6-96231b3b80d8
2015-09-23 21:41:42 +00:00
Alexey Bader cf5dc434bd Run clang-format to unify the switch statement style as suggest here: http://reviews.llvm.org/D12855#246073.
NFC.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@247678 91177308-0d34-0410-b5e6-96231b3b80d8
2015-09-15 12:18:29 +00:00
Alexey Bader a3e40c774f [OpenCL] Add new types for OpenCL 2.0.
Patch by Pedro Ferreira.
Reviewers: pekka.jaaskelainen
Differential Revision: http://reviews.llvm.org/D12855

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@247676 91177308-0d34-0410-b5e6-96231b3b80d8
2015-09-15 11:18:52 +00:00
Peter Collingbourne f29b6351df CFI: Introduce -fsanitize=cfi-icall flag.
This flag causes the compiler to emit bit set entries for functions as well
as runtime bitset checks at indirect call sites. Depends on the new function
bitset mechanism.

Differential Revision: http://reviews.llvm.org/D11857

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@247238 91177308-0d34-0410-b5e6-96231b3b80d8
2015-09-10 02:17:40 +00:00
Alexey Bataev 4de8211781 [OPENMP 4.0] Initial support for array sections.
Adds parsing/sema analysis/serialization/deserialization for array sections in OpenMP constructs (introduced in OpenMP 4.0).
Currently it is allowed to use array sections only in OpenMP clauses that accepts list of expressions.
Differential Revision: http://reviews.llvm.org/D10732


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@245937 91177308-0d34-0410-b5e6-96231b3b80d8
2015-08-25 14:24:04 +00:00
Yaron Keren f49d6b8491 Remove and forbid raw_svector_ostream::flush() calls.
After r244870 flush() will only compare two null pointers and return,
doing nothing but wasting run time. The call is not required any more
as the stream and its SmallString are always in sync.

Thanks to David Blaikie for reviewing.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@244928 91177308-0d34-0410-b5e6-96231b3b80d8
2015-08-13 18:12:56 +00:00
Peter Collingbourne 36d9fb5902 AST: Implement mangling support for function types without a prototype.
Function types without prototypes can arise when mangling a function type
within an overloadable function in C. We mangle these as the absence of
any parameter types (not even an empty parameter list).

Differential Revision: http://reviews.llvm.org/D11848

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@244374 91177308-0d34-0410-b5e6-96231b3b80d8
2015-08-07 23:25:47 +00:00
Benjamin Kramer 6bcb1609b9 [AST] Really allocate a SmallVector to the right size.
set_size only resets the end pointer and asserts if it is used to grow
the buffer. This would crash when mangling a float with more than 80 bits,
add a test with a ppc double double (128 bits).

Found by inspection.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@243979 91177308-0d34-0410-b5e6-96231b3b80d8
2015-08-04 13:34:50 +00:00
Douglas Gregor ffad82b290 Implement the Objective-C __kindof type qualifier.
The __kindof type qualifier can be applied to Objective-C object
(pointer) types to indicate id-like behavior, which includes implicit
"downcasting" of __kindof types to subclasses and id-like message-send
behavior. __kindof types provide better type bounds for substitutions
into unspecified generic types, which preserves more type information.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@241548 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-07 03:58:42 +00:00
Alexey Bataev 76af433873 [OPENMP] Introduced type trait "__builtin_omp_required_simd_align" for default simd alignment.
Adds type trait "__builtin_omp_required_simd_align" after discussions here http://reviews.llvm.org/D9894
Differential Revision: http://reviews.llvm.org/D10597


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@241237 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-02 03:40:19 +00:00
Alexander Kornienko 8ca7705aa3 Revert r240270 ("Fixed/added namespace ending comments using clang-tidy").
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@240353 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-22 23:07:51 +00:00
Alexander Kornienko ac58acc7f2 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.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@240270 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-22 09:47:44 +00:00
Peter Collingbourne 4655bf2be1 CFI: Implement bitset emission for the Microsoft ABI.
Clang's control flow integrity implementation works by conceptually attaching
"tags" (in the form of bitset entries) to each virtual table, identifying
the names of the classes that the virtual table is compatible with. Under
the Itanium ABI, it is simple to assign tags to virtual tables; they are
simply the address points, which are available via VTableLayout. Because any
overridden methods receive an entry in the derived class's virtual table,
a check for an overridden method call can always be done by checking the
tag of whichever derived class overrode the method call.

The Microsoft ABI is a little different, as it does not directly use address
points, and overrides in a derived class do not cause new virtual table entries
to be added to the derived class; instead, the slot in the base class is
reused, and the compiler needs to adjust the this pointer at the call site
to (generally) the base class that initially defined the method. After the
this pointer has been adjusted, we cannot check for the derived class's tag,
as the virtual table may not be compatible with the derived class. So we
need to determine which base class we have been adjusted to.

Specifically, at each call site, we use ASTRecordLayout to identify the most
derived class whose virtual table is laid out at the "this" pointer offset
we are using to make the call, and check the virtual table for that tag.

Because address point information is unavailable, we "reconstruct" it as
follows: any virtual tables we create for a non-derived class receive a tag
for that class, and virtual tables for a base class inside a derived class
receive a tag for the base class, together with tags for any derived classes
which are laid out at the same position as the derived class (and therefore
have compatible virtual tables).

Differential Revision: http://reviews.llvm.org/D10520

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@240117 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-19 02:30:43 +00:00
Yunzhong Gao e43fe24e60 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



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@239446 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-10 00:27:52 +00:00
David Majnemer 02193ce76c [ItaniumMangle] Mangle long double as __float128 for some Power targets
GCC mangles long double like __float128 in order to support
compatibility with ABI variants which had a different interpretation of
long double.

This fixes PR23791.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@239421 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-09 18:05:33 +00:00
Justin Bogner a9e31d6e08 Modernize some doc comments. NFC
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@238006 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-22 06:48:13 +00:00
David Majnemer 24a219dcf3 [ItaniumMangle] Fix a typo.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@238002 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-22 05:54:24 +00:00
Douglas Gregor f6b91e6f16 Itanium mangler: don't trip an assertion when unresolved members have implicit bases.
When we find a member of the current instantation, the base of the
unresolved member expression is implicit; use nullptr for such
bases. This is not a change in behavior: the AST already contains null
in such cases, so non-asserts builds do the right thing already. Fixes
rdar://problem/21020559.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@237929 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-21 18:28:18 +00:00
Kevin Qin d13c501b4c [AArch64 ACLE] Allow to define poly64_t as 'unsigned long long' on LLP64 system.
This fixes PR23414 as well.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@237348 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-14 08:18:05 +00:00
Reid Kleckner eec5f41a53 Reland r234613 (and follow-ups 234614, 234616, 234618)
The frameescape intrinsic cannot be inlined, so I fixed the inliner in
r234937. This should address PR23216.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@234942 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-14 20:59:00 +00:00
Nico Weber 804f40bf60 Revert r234613 (and follow-ups 234614, 234616, 234618), it caused PR23216.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@234789 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-13 20:04:22 +00:00
Nico Weber a5b191aa79 Revert r234786, it contained a bunch of stuff I did not mean to commit.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@234787 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-13 20:03:03 +00:00
Nico Weber 5aaa165ebe Revert r234613 (and follow-ups 234614, 234616, 234618), it caused PR23216.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@234786 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-13 20:01:20 +00:00
Reid Kleckner 48d7c1dcf4 [SEH] Re-land r234532, but use internal linkage for all SEH helpers
Even though these symbols are in a comdat group, the Microsoft linker
really wants them to have internal linkage.

I'm planning to tweak the mangling in a follow-up change. This is a
straight revert with a 1-line fix.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@234613 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-10 17:34:52 +00:00
Nico Weber 5e087128f8 Revert r234532 for a bit, it very likely caused http://crbug.com/475768
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@234563 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-10 04:33:03 +00:00
Reid Kleckner 1a48caef66 [SEH] Outline finally blocks using the new variable capture support
WinEHPrepare was going to have to pattern match the control flow merge
and split that the old lowering used, and that wasn't really feasible.

Now we can teach WinEHPrepare to pattern match this, which is much
simpler:
  %fp = call i8* @llvm.frameaddress(i32 0)
  call void @func(iN [01], i8* %fp)

This prototype happens to match the prototype used by the Win64 SEH
personality function, so this is really simple.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@234532 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-09 20:37:24 +00:00
David Majnemer 889c281d5b MS ABI: Implement copy-ctor closures, finish implementing throw
This adds support for copy-constructor closures.  These are generated
when the C++ runtime has to call a copy-constructor with a particular
calling convention or with default arguments substituted in to the call.

Because the runtime has no mechanism to call the function with a
different calling convention or know-how to evaluate the default
arguments at run-time, we create a thunk which will do all the
appropriate work and package it in a way the runtime can use.

Differential Revision: http://reviews.llvm.org/D8225

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@231952 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-11 18:36:39 +00:00
Richard Smith 4714fcc86a For PR22870: produce an error rather than asserting if a designated initializer appears in a signature.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@231892 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-11 00:12:17 +00:00
Yaron Keren 1acd90385d Teach raw_ostream to accept SmallString.
Saves adding .str() call to any raw_ostream << SmallString usage
and a small step towards making .str() consistent in the ADTs by
removing one of the SmallString::str() use cases, discussion at

http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20141013/240026.html

I'll update the Phabricator patch http://reviews.llvm.org/D6372
for review of the Twine SmallString support, it's more complex
than this one.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@231763 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-10 07:33:23 +00:00
Peter Collingbourne f9d64b33eb Implement Control Flow Integrity for virtual calls.
This patch introduces the -fsanitize=cfi-vptr flag, which enables a control
flow integrity scheme that checks that virtual calls take place using a vptr of
the correct dynamic type. More details in the new docs/ControlFlowIntegrity.rst
file.

It also introduces the -fsanitize=cfi flag, which is currently a synonym for
-fsanitize=cfi-vptr, but will eventually cover all CFI checks implemented
in Clang.

Differential Revision: http://reviews.llvm.org/D7424

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@230055 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-20 20:30:56 +00:00
David Majnemer 95a3256ad0 Itanium ABI: Pack expansions change the arity of expressions to unknown
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@229918 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-19 21:41:48 +00:00
NAKAMURA Takumi f23ade4bd4 CXXNameMangler::mangleUnresolvedPrefix(): Prune an obsolete \param, according to r229809. [-Wdocumentation]
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@229823 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-19 07:14:26 +00:00
David Majnemer 2438ec3689 Itanium ABI: Don't pass nullptr to a bool argument
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@229822 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-19 05:51:14 +00:00
David Majnemer 7f61fcc7a0 Itanium ABI: Properly qualify the destructor-name
We didn't have enough qualificaiton before the scope specifier and we
had too much qualification in the destructor name itself.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@229809 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-19 02:16:16 +00:00
David Majnemer ea5dfab021 Itanium ABI: Write a character instead of a string literal
No functional change intended.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@229726 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-18 19:08:14 +00:00
David Majnemer 16806a15ec Itanium ABI: Properly mangle extern "C" template arguments
extern "C" declarations should be considered like global declarations
for mangling purposes.

Differential Revision: http://reviews.llvm.org/D7718

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@229724 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-18 19:08:11 +00:00
David Majnemer 906d41ab2e Itanium ABI: Mangle <mangled-name> according to the ABI
We attempted to be compatible with GCC's buggy mangling for templates
with a declaration for a template argument.

However, we weren't completely successful in copying their bug in cases
like:
  char foo;
  template <char &C> decltype(C) f() { return foo; };
  template char &f<foo>();

Instead, just follow the ABI specification.  This fixes PR22621.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@229644 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-18 07:47:09 +00:00
David Majnemer d2ec4c03b3 Itanium ABI: Improve our mangling of <destructor-name>
Our mangling of <destructor-name> wasn't quite right: we'd introduce
mangling substitutions where one shouldn't be possible.  We also didn't
correctly handle the case where the destroyed type was not dependent but
still a TemplateSpecializationType.

N.B. There isn't a mangling for a template-template parameter showing up
as the destroyed type.  We do the 'obvious' thing and mangle the index
of the parameter.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@229615 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-18 02:28:01 +00:00
David Majnemer 201a5fe8c9 ItaniumMangle: Correctly mangle <base-unresolved-name>
We had two bugs:
- We were missing the "on" prefix for unresolved operators.
- We didn't handle the mangling of destructors at all.

This fixes PR22584.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@229255 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-14 13:23:54 +00:00
Richard Smith 7cb6bf2c0c PR22465: when performing list-initialization for a class type C, if we see an
initializer of the form {x}, where x is of type C or a type derived from C,
perform *non-list* initialization of the entity from x, but create a
CXXConstructExpr that knows that we used list-initialization syntax.

Plus some fixes to ensure we mangle correctly in this and related cases.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@228276 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-05 07:02:11 +00:00
Richard Smith 789175b49a Various fixes to mangling of list-initialization.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@228274 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-05 06:15:50 +00:00
Reid Kleckner 4702b3a507 Initial support for Win64 SEH IR emission
The lowering looks a lot like normal EH lowering, with the exception
that the exceptions are caught by executing filter expression code
instead of matching typeinfo globals. The filter expressions are
outlined into functions which are used in landingpad clauses where
typeinfo would normally go.

Major aspects that still need work:
- Non-call exceptions in __try bodies won't work yet. The plan is to
  outline the __try block in the frontend to keep things simple.
- Filter expressions cannot use local variables until capturing is
  implemented.
- __finally blocks will not run after exceptions. Fixing this requires
  work in the LLVM SEH preparation pass.

The IR lowering looks like this:

// C code:
bool safe_div(int n, int d, int *r) {
  __try {
    *r = normal_div(n, d);
  } __except(_exception_code() == EXCEPTION_INT_DIVIDE_BY_ZERO) {
    return false;
  }
  return true;
}

; LLVM IR:
define i32 @filter(i8* %e, i8* %fp) {
  %ehptrs = bitcast i8* %e to i32**
  %ehrec = load i32** %ehptrs
  %code = load i32* %ehrec
  %matches = icmp eq i32 %code, i32 u0xC0000094
  %matches.i32 = zext i1 %matches to i32
  ret i32 %matches.i32
}

define i1 zeroext @safe_div(i32 %n, i32 %d, i32* %r) {
  %rr = invoke i32 @normal_div(i32 %n, i32 %d)
      to label %normal unwind to label %lpad

normal:
  store i32 %rr, i32* %r
  ret i1 1

lpad:
  %ehvals = landingpad {i8*, i32} personality i32 (...)* @__C_specific_handler
      catch i8* bitcast (i32 (i8*, i8*)* @filter to i8*)
  %ehptr = extractvalue {i8*, i32} %ehvals, i32 0
  %sel = extractvalue {i8*, i32} %ehvals, i32 1
  %filter_sel = call i32 @llvm.eh.seh.typeid.for(i8* bitcast (i32 (i8*, i8*)* @filter to i8*))
  %matches = icmp eq i32 %sel, %filter_sel
  br i1 %matches, label %eh.except, label %eh.resume

eh.except:
  ret i1 false

eh.resume:
  resume
}

Reviewers: rjmccall, rsmith, majnemer

Differential Revision: http://reviews.llvm.org/D5607

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@226760 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-22 01:36:17 +00:00