Commit Graph

199 Commits

Author SHA1 Message Date
Anders Carlsson a03f3a85cb When building with optimizations, emit vtables where the key is not in the
current translation unit as available_externally. 

This helps devirtualize the second example in PR3100, comment 18:

struct S { S() {}; virtual void xyzzy(); };
inline void foo(S *s) { s->xyzzy(); }
void bar() { S s; foo(&s); }

This involved four major changes:

1. In DefineUsedVTables, always mark virtual member functions as referenced for
   non-template classes and class template specializations.
2. In CodeGenVTables::ShouldEmitVTableInThisTU return true if optimizations are
   enabled, even if the key function is not implemented in this translation 
   unit. We don't ever do this for code compiled with -fapple-kext, because we
   don't ever want to devirtualize virtual member function calls in that case.
3. Give the correct linkage for vtables where the key function is not defined.
4. Update the linkage for RTTI structures when necessary.

llvm-svn: 124565
2011-01-30 20:45:54 +00:00
Anders Carlsson 265aa7c070 Change CodeGenModule::setTypeVisibility to take a TypeVisibilityKind enum instead of an "IsForRTTI" flag.
llvm-svn: 124546
2011-01-29 20:24:48 +00:00
Anders Carlsson c6a47895f7 Get rid of an unneeded parameter from setGlobalVisibility.
llvm-svn: 124541
2011-01-29 19:39:23 +00:00
Anders Carlsson 883fc72c3c Make emitting a VTT a two-step process, much like emitting a VTable. You first get the address of the VTT, and then pass it to EmitVTTDefinition.
llvm-svn: 124539
2011-01-29 19:16:51 +00:00
Anders Carlsson 93be9a90cc Use CGM.CreateOrReplaceCXXRuntimeVariable in CGVTables.cpp
llvm-svn: 124538
2011-01-29 18:25:07 +00:00
Anders Carlsson fd4834061c Remove IsDefinition from CodeGenModule::setTypeVisibility; it is always true.
llvm-svn: 124529
2011-01-29 05:26:32 +00:00
Fariborz Jahanian 9f9438b314 More work to support -fapple-kext regarding
indirect vf calls and addition of extra entry
at bottom of vtbls.

llvm-svn: 124507
2011-01-28 23:42:29 +00:00
Rafael Espindola facb7d0ade Also set unnamed_addr on declarations.
llvm-svn: 123531
2011-01-15 08:23:14 +00:00
Rafael Espindola d09776b945 Only add unnamed_addr to definitions.
llvm-svn: 123354
2011-01-13 01:12:55 +00:00
Rafael Espindola 5674c644cf Add unnamed_addr to vtables.
llvm-svn: 123272
2011-01-11 21:10:26 +00:00
Anders Carlsson 7f95cd1817 Rename RecordLayout::getPrimaryBaseWasVirtual to isPrimaryBaseVirtual.
llvm-svn: 120133
2010-11-24 23:12:57 +00:00
Anders Carlsson cadbc463e2 Move code off the primary base info iterator. No functionality change.
llvm-svn: 120132
2010-11-24 23:04:03 +00:00
John McCall 478382521e When re-using a vtable slot for the nearest overridden method, just because
there's no return adjustment from the overridden to the overrider doesn't
mean there isn't a return adjustment from the overrider to the final
overrider.  This matters if we're emitting a virtual this-adjustment thunk
because the overrider virtually inherits from the class providing the
nearest overridden method.  Do the appropriate return adjustment in this case.

Fixes PR7611.

llvm-svn: 118466
2010-11-09 01:18:05 +00:00
Anders Carlsson fd88a6160d Rename getBaseClassOffset to getBaseClassOffsetInBits and introduce a getBaseClassOffset which returns the offset in CharUnits. Do the same thing for getVBaseClassOffset.
llvm-svn: 117881
2010-10-31 23:22:37 +00:00
John McCall c273f24196 Better solution: calculate the visibility of functions and variables
independently of whether they're definitions, then teach IR generation to
ignore non-explicit visibility when emitting declarations.  Use this to
make sure that RTTI, vtables, and VTTs get the right visibility.

More of rdar://problem/8613093

llvm-svn: 117781
2010-10-30 11:50:40 +00:00
Argyrios Kyrtzidis 0c34b138df Make sure the VTables for template instantiations are emitted even if the key function doesn't have a body.
llvm-svn: 116186
2010-10-11 03:25:57 +00:00
John McCall 5d865c3292 Teach IR generation to return 'this' from constructors and destructors
under the ARM ABI.

llvm-svn: 112588
2010-08-31 07:33:07 +00:00
John McCall b3732bb3b7 Just disable the hidden-visibility optimization for now by hiding it behind
a -cc1 option.  The Darwin linker complains about mixed visibility when linking
gcc-built objects with clang-built objects, and the optimization isn't really
that valuable.  Platforms with less ornery linkers can feel free to enable this.

llvm-svn: 110979
2010-08-12 23:36:15 +00:00
John McCall 5513fce96b It turns out that linkers (at least, the Darwin linker) don't necessarily
do the right thing with mixed-visibility symbols, so disable the visibility
optimization where that's possible, i.e. with template classes (since it's
possible that an arbitrary template might be subject to an explicit
instantiation elsewhere).  447.dealII actually does this.

I've put the code under an option that's currently not hooked up to anything.

llvm-svn: 110374
2010-08-05 20:39:18 +00:00
John McCall c8bd9c277b Extend the visibility-hidden optimization to linkonce_odr thunks for
functions with in-line definitions, since such thunks will be emitted at any
use of the function.

Completes the feature work for rdar://problem/7523229.

llvm-svn: 110285
2010-08-04 23:46:35 +00:00
John McCall e16adc2b1e Emit standard-library RTTI with external linkage, not weak_odr.
Apply hidden visibility to most RTTI;  libstdc++ does not rely on exact
pointer equality for the type info (just the type info names).  Apply
the same optimization to RTTI that we do to vtables.

Fixes PR5962.

llvm-svn: 110192
2010-08-04 08:34:44 +00:00
John McCall 8a705c15d9 Extend the hidden-visibility vtables optimization to template classes that
haven't been explicitly instantiated.

llvm-svn: 110189
2010-08-04 06:38:15 +00:00
John McCall 5696d6d316 Emit weak vtables of non-template classes with hidden visibility.
llvm-svn: 110107
2010-08-03 07:24:12 +00:00
Douglas Gregor b412e174db Remove the vast majority of the Destroy methods from the AST library,
since we aren't going to be calling them ever.

llvm-svn: 109377
2010-07-25 18:17:45 +00:00
Douglas Gregor 4f6e8deec4 Make sure to set the visible on a vtable; VTTs and typeinfo already
handle visibility properly. Fixes <rdar://problem/8091955>. 

llvm-svn: 105977
2010-06-14 23:41:45 +00:00
Anders Carlsson fd788405ac Remove now unused code.
llvm-svn: 105448
2010-06-04 00:59:37 +00:00
Anders Carlsson 27860db29e Use CXXRecordDecl::getFinalOverriders to get final overriders. This speeds up vtable layout by moving away from the old final overrider computation code that had O(N^2) complexity in some cases.
llvm-svn: 105447
2010-06-04 00:54:04 +00:00
John McCall 6a7f9f5c8f Don't try to emit the vtable for a class just because we're emitting a
virtual function from it.

Fixes PR7241.

llvm-svn: 105345
2010-06-02 21:22:02 +00:00
Anders Carlsson 04e51cca94 More cleanup.
llvm-svn: 105301
2010-06-01 23:52:26 +00:00
Anders Carlsson 042ce2d8f1 More cleanup.
llvm-svn: 105299
2010-06-01 23:47:05 +00:00
Anders Carlsson 79547c3fbd Cleanup.
llvm-svn: 105296
2010-06-01 23:17:37 +00:00
Anders Carlsson 107b4e096c Remove unused parameter to FinalOverriders::PropagateOverrider.
llvm-svn: 105171
2010-05-30 18:23:41 +00:00
John McCall 23f6626262 Correctly pass aggregates by reference when emitting thunks.
llvm-svn: 104778
2010-05-26 22:34:26 +00:00
John McCall 7cb0220e53 If a function definition has any sort of weak linkage, its static local
variables should have that linkage.  Otherwise, its static local
variables should have internal linkage.  To avoid computing this excessively,
set a function's linkage before we emit code for it.

Previously we were assigning weak linkage to the static variables of
static inline functions in C++, with predictably terrible results.  This
fixes that and also gives better linkage than 'weak' when merging is required.

llvm-svn: 104581
2010-05-25 04:30:21 +00:00
Douglas Gregor c5871f07f0 When generating the call arguments in a thunk to call the thunkee, do
not make copies non-POD arguments or arguments passed by reference:
just copy the pointers directly. This eliminates another source of the
dreaded memcpy-of-non-PODs. Fixes PR7188.

llvm-svn: 104327
2010-05-21 17:55:12 +00:00
Douglas Gregor aa2ac80eaa When creating a this-adjustment thunk where the return value is of C++
class type (that uses a return slot), pass the return slot to the
callee directly rather than allocating new storage and trying to copy
the object. This appears to have been the cause of the remaining two
Boost.Interprocess failures.

llvm-svn: 104215
2010-05-20 05:54:35 +00:00
Douglas Gregor 88d292ccb8 Rework when and how vtables are emitted, by tracking where vtables are
"used" (e.g., we will refer to the vtable in the generated code) and
when they are defined (i.e., because we've seen the key function
definition). Previously, we were effectively tracking "potential
definitions" rather than uses, so we were a bit too eager about emitting
vtables for classes without key functions. 

The new scheme:
  - For every use of a vtable, Sema calls MarkVTableUsed() to indicate
  the use. For example, this occurs when calling a virtual member
  function of the class, defining a constructor of that class type,
  dynamic_cast'ing from that type to a derived class, casting
  to/through a virtual base class, etc.
  - For every definition of a vtable, Sema calls MarkVTableUsed() to
  indicate the definition. This happens at the end of the translation
  unit for classes whose key function has been defined (so we can
  delay computation of the key function; see PR6564), and will also
  occur with explicit template instantiation definitions.
 - For every vtable defined/used, we mark all of the virtual member
 functions of that vtable as defined/used, unless we know that the key
 function is in another translation unit. This instantiates virtual
 member functions when needed.
  - At the end of the translation unit, Sema tells CodeGen (via the
  ASTConsumer) which vtables must be defined (CodeGen will define
  them) and which may be used (for which CodeGen will define the
  vtables lazily). 

From a language perspective, both the old and the new schemes are
permissible: we're allowed to instantiate virtual member functions
whenever we want per the standard. However, all other C++ compilers
were more lazy than we were, and our eagerness was both a performance
issue (we instantiated too much) and a portability problem (we broke
Boost test cases, which now pass).

Notes:
  (1) There's a ton of churn in the tests, because the order in which
  vtables get emitted to IR has changed. I've tried to isolate some of
  the larger tests from these issues.
  (2) Some diagnostics related to
  implicitly-instantiated/implicitly-defined virtual member functions
  have moved to the point of first use/definition. It's better this
  way.
  (3) I could use a review of the places where we MarkVTableUsed, to
  see if I missed any place where the language effectively requires a
  vtable.

Fixes PR7114 and PR6564.

llvm-svn: 103718
2010-05-13 16:44:06 +00:00
Douglas Gregor 1411bb8f76 Fix typo in comment; 80 col violation
llvm-svn: 103204
2010-05-06 22:33:50 +00:00
Chris Lattner 3baada6fd7 Pass the globaldecl into GetOrCreateLLVMFunction so that llvm
function attributes like byval get applied to the function 
definition. This fixes PR7058 and makes i386 llvm/clang bootstrap 
pass all the same tests as x86-64 bootstrap for me (the llvmc 
tests still fail in both).

llvm-svn: 103131
2010-05-05 22:55:13 +00:00
Anders Carlsson 11e5140db9 Vtable -> VTable renames across the board.
llvm-svn: 101666
2010-04-17 20:15:18 +00:00
Anders Carlsson c6db5ab8b2 Fix a bug where we would sometimes incorrectly mark an vtable function as unused.
llvm-svn: 101643
2010-04-17 17:24:33 +00:00
Anders Carlsson 3383e2ad74 Fix another bug where we wouldn't generate secondary vtables for construction vtables in some cases.
llvm-svn: 100998
2010-04-11 22:20:36 +00:00
Anders Carlsson d78b224e91 More renames.
llvm-svn: 100991
2010-04-11 22:07:06 +00:00
Anders Carlsson b41c633a34 Rename a function parameter.
llvm-svn: 100990
2010-04-11 22:03:57 +00:00
Anders Carlsson 343a26b56d Fix a bug where we were adding too many vcall offsets in some cases.
llvm-svn: 100985
2010-04-11 20:04:11 +00:00
Anders Carlsson 0b5522114e Enable an assert and remove a now unnecessary assert.
llvm-svn: 100953
2010-04-10 21:50:08 +00:00
Anders Carlsson 88cf34f2b4 Fix a bug where we would add the same function twice in a vtable.
llvm-svn: 100949
2010-04-10 20:39:29 +00:00
Anders Carlsson be1b9cbc63 Rename VtableComponent and VtableBuilder.
llvm-svn: 100945
2010-04-10 19:13:06 +00:00
Anders Carlsson af2a317e05 Rename CGVtable files to CGVTables.
llvm-svn: 100778
2010-04-08 16:30:25 +00:00