consistent model for handling size expressions for VLAs.

The model is essentially as follows: VLA types own their associated
expression.  In some cases, we need to create multiple VLA types to 
represent a given VLA (for canonical types, or qualifiers on array types,
or type merging).  If we need to create multiple types based off of 
the same VLA declaration, we use the new refcounting functionality so they can 
all own the expression. The VLASizeMap in CodeGenFunction then uses the size
expression to identify the group of VLA types based off of the same original
declaration.

I'm not particularly attached to the VLA types owning the expression, 
but we're stuck with at least until someone comes up with a way 
to walk the VLA expressions for a declaration.

I did the parallel fix in ASTContext for DependentSizedArrayType, but I 
haven't really looked closely at it, so there might still be issues 
there.

I'll clean up the code duplication in ASTContext in a followup commit.

llvm-svn: 79071

llvm-svn: 79059

llvm-svn: 78946

WIP.

llvm-svn: 78841

llvm-svn: 78582

llvm-svn: 78536

llvm-svn: 78515

llvm-svn: 78489

copying non-virtual base classes which have non-trivial
constructor. Work in progress.

llvm-svn: 78436

llvm-svn: 78402

Work in progress.

llvm-svn: 78355

llvm-svn: 77722

been declared as needed.

llvm-svn: 77641

llvm-svn: 77638

llvm-svn: 77608

llvm-svn: 77514

  Type::getAsReferenceType() -> Type::getAs<ReferenceType>()
  Type::getAsRecordType() -> Type::getAs<RecordType>()
  Type::getAsPointerType() -> Type::getAs<PointerType>()
  Type::getAsBlockPointerType() -> Type::getAs<BlockPointerType>()
  Type::getAsLValueReferenceType() -> Type::getAs<LValueReferenceType>()
  Type::getAsRValueReferenceType() -> Type::getAs<RValueReferenceType>()
  Type::getAsMemberPointerType() -> Type::getAs<MemberPointerType>()
  Type::getAsReferenceType() -> Type::getAs<ReferenceType>()
  Type::getAsTagType() -> Type::getAs<TagType>()
  
And remove Type::getAsReferenceType(), etc.

This change is similar to one I made a couple weeks ago, but that was partly
reverted pending some additional design discussion. With Doug's pending smart
pointer changes for Types, it seemed natural to take this approach.

llvm-svn: 77510

llvm-svn: 77012

llvm-svn: 76862

llvm-svn: 76498

llvm-svn: 76493

llvm-svn: 76473

llvm-svn: 76365

 - Emit variable declarations as "simple", we want to avoid forcing the creation
   of a dummy basic block, but still need to make the variable available for
   later use.

 - With that, we can now skip IRgen for other unreachable statements (which
   don't define a label).

 - Anders, I added two fixmes on calls to EmitVLASize, can you check them?

llvm-svn: 76361

until Doug Gregor's Type smart pointer code lands (or more discussion occurs).
These methods just call the new Type::getAs<XXX> methods, so we still have
reduced implementation redundancy. Having explicit getAsXXXType() methods makes
it easier to set breakpoints in the debugger.

llvm-svn: 76193

Replaced Type::getAsLValueReferenceType(), Type::getAsRValueReferenceType(), Type::getAsMemberPointerType(), Type::getAsTagType(), and Type::getAsRecordType() with their Type::getAs<XXX> equivalents.

llvm-svn: 76139

This method is intended to eventually replace the individual
Type::getAsXXXType<> methods.

The motivation behind this change is twofold:

1) Reduce redundant implementations of Type::getAsXXXType() methods. Most of
them are basically copy-and-paste.

2) By centralizing the implementation of the getAs<Type> logic we can more
smoothly move over to Doug Gregor's proposed canonical type smart pointer
scheme.

Along with this patch:

a) Removed 'Type::getAsPointerType()'; now clients use getAs<PointerType>.
b) Removed 'Type::getAsBlockPointerTypE()'; now clients use getAs<BlockPointerType>.

llvm-svn: 76098

llvm-svn: 75705

llvm-svn: 75446

llvm-svn: 75041

Timings showed no significant difference before and after the commit.

llvm-svn: 74504

The implementations of these methods can Use Decl::getASTContext() to get the ASTContext.

This commit touches a lot of files since call sites for these methods are everywhere.
I used pre-tokenized "carbon.h" and "cocoa.h" headers to do some timings, and there was no real time difference between before the commit and after it.

llvm-svn: 74501

llvm-svn: 73702

When possible, don't emit the cleanup block. Instead, just move the instructions to the current block.

llvm-svn: 72654

actually necessary in some obscure cases.

llvm-svn: 72585

tried other things that might trip, but they all worked.

llvm-svn: 72584

llvm-svn: 72578

llvm-svn: 71937

llvm-svn: 70155

the type assigned by sema (and is visible with sizeof(__func__) for
example) has nothing to do with what codegen ends up producing.
We should eventually add a method on PredefinedExpr to handle this.
In the meantime, just set up some framework and add some fixme's.

llvm-svn: 69872