Commit Graph

317 Commits

Author SHA1 Message Date
David Blaikie aa347f9392 Removing a bunch of dead returns/breaks after llvm_unreachables.
llvm-svn: 140407
2011-09-23 20:26:49 +00:00
David Blaikie 83d382b1ca Switch assert(0/false) llvm_unreachable.
llvm-svn: 140367
2011-09-23 05:06:16 +00:00
Douglas Gregor e8bbc12152 Extend the ASTContext constructor to delay the initialization of
builtin types (When requested). This is another step toward making
ASTUnit build the ASTContext as needed when loading an AST file,
rather than doing so after the fact. No actual functionality change (yet).

llvm-svn: 138985
2011-09-02 00:18:52 +00:00
Eli Friedman f5dfb31df0 Revert bad change. (It may look equivalent, but it isn't.)
llvm-svn: 137132
2011-08-09 18:16:09 +00:00
Eli Friedman f481ccafd8 Cleanup; no functionality change.
llvm-svn: 137126
2011-08-09 17:38:12 +00:00
Chris Lattner 0e62c1cc0b remove unneeded llvm:: namespace qualifiers on some core types now that LLVM.h imports
them into the clang namespace.

llvm-svn: 135852
2011-07-23 10:55:15 +00:00
Chris Lattner 2192fe50da de-constify llvm::Type, patch by David Blaikie!
llvm-svn: 135370
2011-07-18 04:24:23 +00:00
Chris Lattner 8806e32f16 Rename CGT::VerifyFuncTypeComplete to isFuncTypeConvertible since
it is a predicate, not an action.  Change the return type to be a bool,
not the incomplete member.  Enhace it to detect the recursive compilation
case, allowing us to compile Eli's testcase on llvmdev:

struct T {
 struct T (*p)(void);
} t;

into:

%struct.T = type { {}* }

@t = common global %struct.T zeroinitializer, align 8

llvm-svn: 134853
2011-07-10 00:18:59 +00:00
Jay Foad 83be361b8a Replace the existing forms of ConstantArray::get() with a single form
that takes an ArrayRef.

llvm-svn: 133615
2011-06-22 09:24:39 +00:00
Anders Carlsson d6f1518cc9 Fix another regression from the "skip vtable pointer initialization"
optimization. Make sure to require a vtable when trying to get the address
of a VTT, otherwise we would never end up emitting the VTT.

llvm-svn: 131400
2011-05-16 04:08:36 +00:00
Eli Friedman 49a94b1c7c Add an implementation of thunks for varargs methods. The implementation is a bit messy, but it is correct as long as the method in question doesn't use indirect gotos. A couple of possible alternative implementations are outlined in FIXME's in this patch. rdar://problem/8077308 .
llvm-svn: 130993
2011-05-06 17:27:27 +00:00
Eli Friedman 43dca6a8d2 Simplify code a bit by using CallArgList::add. No intended functionality change.
llvm-svn: 130699
2011-05-02 17:57:46 +00:00
Anders Carlsson e5ec21c977 Change CollectPrimaryBases to collect the bases in the right order. Fixes one half of PR9660.
llvm-svn: 129252
2011-04-10 18:00:32 +00:00
Anders Carlsson 68aad14dd3 Make -fdump-vtable-layouts also dump vtable indices for all virtual member functions in the class.
llvm-svn: 129250
2011-04-10 17:42:45 +00:00
Ken Dyck bb4e977218 [Reapply r128776, modified so that it does not break debug info.]
Change the return type of CodeGenVTables::getVirtualBaseOffsetOffset() to
CharUnits. No change in functionality intended.

llvm-svn: 129072
2011-04-07 12:37:09 +00:00
Ken Dyck 3a09bc5ab0 [Reapply r128773. This is not the source of the issues Devang was seeing
with debug info.]

Use CharUnits for the offsets in the VirtualBaseClassOffsetOffsetsMapTy. No
change in functionality intended.

llvm-svn: 129048
2011-04-07 01:22:42 +00:00
Ken Dyck 25c82240e9 [Reapply r128771. It wasn't the source of the issues Devang saw with debug
info.]

Use CharUnits for the offset type in the ClassNamesAndOffsets map in
dumpLayout(). No change in functionality intended.

llvm-svn: 129046
2011-04-07 00:59:42 +00:00
Ken Dyck 42a9d29c2c Reapply r128770. It's not the cause of the issues Devang saw with debug info.
Use CharUnits for the offsets in the VBaseOffsetOffsetsMapTy types. No
change in functionality intended.

llvm-svn: 129043
2011-04-07 00:55:01 +00:00
Devang Patel 84852bbb42 Revert r128770, r128771, r128773 and r128776 for now. It breaks debug info.
llvm-svn: 128842
2011-04-04 20:36:06 +00:00
Ken Dyck 1473c9a7c4 Change the return type of CodeGenVTables::getVirtualBaseOffsetOffset() to
CharUnits. No change in functionality intended.

llvm-svn: 128776
2011-04-02 17:52:22 +00:00
Ken Dyck 1b23db93df Use CharUnits for the offsets in the VirtualBaseClassOffsetOffsetsMapTy. No
change in functionality intended.

llvm-svn: 128773
2011-04-02 17:13:02 +00:00
Ken Dyck cf4ef5314f Use CharUnits for the offset type in the ClassNamesAndOffsets map in
dumpLayout(). No change in functionality intended.

llvm-svn: 128771
2011-04-02 17:03:24 +00:00
Ken Dyck 1eac9f1546 Use CharUnits for the offsets in the VBaseOffsetOffsetsMapTy types. No
change in functionality intended.

llvm-svn: 128770
2011-04-02 16:57:20 +00:00
Ken Dyck 6b20919317 Convert BaseOffset::NonVirtualOffset to CharUnits. No change in
functionality intended.

llvm-svn: 128756
2011-04-02 01:32:03 +00:00
Ken Dyck 872d74a591 Convert offset parameters and return values of VTableComponent methods to
CharUnits. No change in functionality intended.

llvm-svn: 128754
2011-04-02 01:14:48 +00:00
Ken Dyck 496906629b Convert the offsets in VCallOffsetMap to CharUnits. No change in
functionality intended.

llvm-svn: 128753
2011-04-02 00:51:15 +00:00
Ken Dyck eff7fe645b Convert offset parameters of VTableBuilder::IsOverriderUsed() to CharUnits.
No change in functionality intended.

llvm-svn: 128752
2011-04-02 00:44:58 +00:00
Ken Dyck 4680e9219a Convert the return value of
VCallAndVBaseOffsetBuilder::getCurrentOffsetOffset() to CharUnits. No change
in functionality intended.

llvm-svn: 128603
2011-03-31 01:08:46 +00:00
Ken Dyck 47e1e54343 Convert the OffsetInLayoutClass parameter of
VCallAndVBaseOffsetBuilder::AddVBaseOffsets() to CharUnits. No change in
functionality intended.

llvm-svn: 128600
2011-03-31 00:56:47 +00:00
Ken Dyck 1a93b3b080 Convert the OffsetInLayoutClass of the VCallAndVBaseOffsetBuilder
constructor to CharUnits. No change in functionality intended.

llvm-svn: 128598
2011-03-31 00:48:04 +00:00
Ken Dyck 9b32ee1611 Convert the RealBaseOffset parameter of
VCallAndVBaseOffsetBuilder::AddVCallAndVBaseOffsets() to
CharUnits. No change in functionality intended.

llvm-svn: 128596
2011-03-31 00:37:24 +00:00
Jay Foad 20c0f02cc5 Remove PHINode::reserveOperandSpace(). Instead, add a parameter to
PHINode::Create() giving the (known or expected) number of operands.

llvm-svn: 128538
2011-03-30 11:28:58 +00:00
Ken Dyck b3ba775523 Convert the offset parameter of
VCallAndVBaseOffsetBuilder::AddVCallOffsets() to CharUnits. No change in
functionality intended.

llvm-svn: 128531
2011-03-30 10:11:40 +00:00
Ken Dyck 075de167f8 Convert local offset variable to CharUnits in AddVCallOffsets. No change in
functionality intended.

llvm-svn: 128522
2011-03-30 01:21:33 +00:00
Ken Dyck 078f3e6905 Convert a local offset variable to CharUnits. No change in functionality
intended.

llvm-svn: 128521
2011-03-30 01:14:22 +00:00
Ken Dyck 032a903982 Convert the OffsetInLayoutClass parameter of DeterminePrimaryVirtualBases()
to CharUnits. No change in functionality intended.

llvm-svn: 128520
2011-03-30 01:10:23 +00:00
Ken Dyck 45956a467e Convert the OffsetInLayoutClass parameter of LayoutSecondaryVTables to
CharUnits. No change in functionality intended.

llvm-svn: 128516
2011-03-30 00:50:28 +00:00
Ken Dyck f9742cca31 Convert offset parameter in LayoutPrimaryAndSecondaryVTables() to CharUnits.
No change in functionality intended.

llvm-svn: 128393
2011-03-27 20:33:38 +00:00
Ken Dyck 9a7e532dd8 Convert VTableBuilder::MostDerivedClassOffset to CharUnits. No change in
functionality intended.

llvm-svn: 128392
2011-03-27 20:20:28 +00:00
Ken Dyck 0d5804a622 Convert FinalOverriders::MostDerivedClassOffset to CharUnits. No change in
functionality intended.

llvm-svn: 128391
2011-03-27 20:10:29 +00:00
Ken Dyck 5f3601d35a Remove a fixed FIXME comment (the base offset has already been converted to
CharUnits).

llvm-svn: 128386
2011-03-27 19:19:52 +00:00
Ken Dyck f4be03ae04 Convert the offset parameters of AddMethods() to CharUnits. No change in
functionality intended.

llvm-svn: 128385
2011-03-27 19:15:11 +00:00
Ken Dyck f736d9cb75 Convert the BaseOffsetInLayoutClass parameter of ComputeThisAdjustment() to
CharUnits. No change in functionality intended.

llvm-svn: 128384
2011-03-27 19:03:44 +00:00
Ken Dyck 7d876f3649 Convert offset members in MethodInfo to CharUnits. No change in
functionality intended.

llvm-svn: 128383
2011-03-27 18:57:53 +00:00
John McCall 358d056c14 We were emitting construction v-tables with internal linkage all the time.
Emit them instead with the linkage of the VTT.

I'm actually really ambivalent about this;  it's what GCC does, but outside
of improving code size (if the linkage is coalescing), I'm not sure it's
at all relevant.  Construction vtables are naturally referenced only by the
VTT, which is itself only referenced by complete-object constructors and
destructors;  giving the construction vtables possibly-external linkage is
important if you have an optimization that drills through the VTT to a
reference to a particular construction vtable which it cannot just emit
itself.

llvm-svn: 128374
2011-03-27 09:00:25 +00:00
Douglas Gregor 1baf38f5a6 On Mac OS X, the presence of an 'availability' attribute for that
platform implies default visibility. To achieve these, refactor our
lookup of explicit visibility so that we search for both an explicit
VisibilityAttr and an appropriate AvailabilityAttr, favoring the
VisibilityAttr if it is present.

llvm-svn: 128336
2011-03-26 12:10:19 +00:00
Ken Dyck 58863dc46a Convert the OffsetInLayoutClass parameter of
FinalOverriders::ComputeBaseOffsets() to CharUnits. No change in
functionality intended.

llvm-svn: 128323
2011-03-26 01:36:26 +00:00
Ken Dyck 785cbdb6da Convert FinalOverriders::Offset to CharUnits. No change in functionality
intended.

llvm-svn: 128321
2011-03-26 01:29:16 +00:00
Ken Dyck 808457cfd6 Convert offset in MethodBaseOffsetPairTy to CharUnits. No change in
functionality intended.

llvm-svn: 128318
2011-03-26 01:18:17 +00:00
Ken Dyck 70b47e08dc Convert the offsets in SubobjectOffsetMapTy to CharUnits. No change in
functionality intended.

llvm-svn: 128317
2011-03-26 01:09:13 +00:00
Ken Dyck ce81203d9b Convert several local variables to CharUnits. No change in functionality
intended.

llvm-svn: 128315
2011-03-26 00:51:24 +00:00
Ken Dyck 16ffcac1a2 Convert the BaseOffset member of BaseSubobject to CharUnits from bits. No
change in functionality intended.

llvm-svn: 128190
2011-03-24 01:21:01 +00:00
John McCall 32ea969415 Use a slightly more semantic interface for emitting call arguments.
llvm-svn: 127494
2011-03-11 20:59:21 +00:00
John McCall 5fe009660d Tame this assert, hopefully fixing self-host.
llvm-svn: 127319
2011-03-09 07:12:35 +00:00
John McCall a738c25f5e Use the "undergoes default argument promotion" bit on parameters to
simplify the logic of initializing function parameters so that we don't need
both a variable declaration and a type in FunctionArgList.  This also means
that we need to propagate the CGFunctionInfo down in a lot of places rather
than recalculating it from the FAL.  There's more we can do to eliminate
redundancy here, and I've left FIXMEs behind to do it.

llvm-svn: 127314
2011-03-09 04:27:21 +00:00
Tilmann Scheller 99cc30c371 Revert "Add CC_Win64ThisCall and set it in the necessary places."
This reverts commit 126863.

llvm-svn: 126886
2011-03-02 21:36:49 +00:00
Tilmann Scheller e60baf731b Revert "Add preliminary support for MSVC-style vtables."
This reverts commit 126865.

llvm-svn: 126876
2011-03-02 20:40:50 +00:00
Tilmann Scheller a6c995dbb2 Add preliminary support for MSVC-style vtables.
llvm-svn: 126865
2011-03-02 19:38:28 +00:00
Tilmann Scheller 454464b491 Add CC_Win64ThisCall and set it in the necessary places.
llvm-svn: 126863
2011-03-02 19:36:23 +00:00
Rafael Espindola 3968cd0f7b For consistency, use llvm::raw_ostream in the rest of the mangle api.
llvm-svn: 125360
2011-02-11 02:52:17 +00:00
John McCall ad7c5c1657 Reorganize CodeGen{Function,Module} to eliminate the unfortunate
Block{Function,Module} base class.  Minor other refactorings.

Fixed a few address-space bugs while I was there.

llvm-svn: 125085
2011-02-08 08:22:06 +00:00
Anders Carlsson e866d44417 Fix self-host; if a thunk already exists and has available_externally linkage, we should change its linkage instead of asserting.
llvm-svn: 124986
2011-02-06 20:09:44 +00:00
Anders Carlsson 8b02183ff3 When building with optimizations, emit thunks with available_externally linkage so devirtualized function calls can also be de-thunked.
llvm-svn: 124984
2011-02-06 18:31:40 +00:00
Anders Carlsson fe8a9939f9 Simplify thunks code.
llvm-svn: 124983
2011-02-06 17:15:43 +00:00
Anders Carlsson 73f97534b0 Pass a 'ForVTable' flag to GetAddrOfThunk and pass it along to GetOrCreateLLVMFunction so that we
won't assert when building a thunk for an implicit virtual member function that is not marked used.

llvm-svn: 124967
2011-02-05 18:48:55 +00:00
Anders Carlsson 3c23948481 Re-land r124768, with a fix for PR9130.
We now emit everything except unused implicit virtual member functions when building the vtable.

llvm-svn: 124935
2011-02-05 04:35:53 +00:00
Rafael Espindola af5b92e8f7 Revert 124768.
This reopens PR99114, but that one at least can be avoided with an #include.
PR9130 cannot.

llvm-svn: 124780
2011-02-03 06:30:58 +00:00
Anders Carlsson bac84bef65 Don't try to mark virtual members referenced for classes where the key function
is not defined in the current translation unit. Doing so lead to compile errors
such as PR9114.

Instead, when CodeGen is building the vtable, don't try to emit a definition
for functions that aren't marked used in the current translation unit.
Fixes PR9114.

llvm-svn: 124768
2011-02-03 02:08:44 +00:00
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