too "conservative").

Several revisions to UninitializedValues checker after testing.  We
now appear to be working correctly (probably some bugs still, but main
functionality appears to be there).  Implemented careful emitting of
warnings so that we wouldn't get a cascade of warnings for simply not
defining a single variable and using it everywhere.  This way the
warnings point closer to the root cause rather than "symptoms" from
using values derived from uninitialized variables.

llvm-svn: 42067

llvm-svn: 42056

globals and function parameters.

llvm-svn: 42055

for reporting errors and running the checker.

llvm-svn: 42046

llvm-svn: 42041

mechanism can be implemented simply by affixing the Observer to an
analysis meta data, so it doesn't need to be a required type.  This
also permits analyses not to implement an Observer if it doesn't make
sense.

Changed "DataflowValues::MetaDataTy" to
"DataflowValues::AnalysisDataTy" to reflect that the type
enscapsulated the data associated with analyzing a given CFG.

Changed CFGStmtVisitor::BlockStmt_VisitImplicitControlFlowStmt(Stmt*)
to ...VisitImplicitControlFlowExpr(Expr*).  The type narrowing is more
precise and more useful to clients.

Added CFGStmtVisitor::BlockStmt_VisitExpr to reflect the visitation of
expressions at the block statement level.  This captures all implicit
control-flow statements as well as other expressions that are hoisted
to the block level (such as conditions for terminators and function
calls).  This is especially useful for dataflow analysis.

llvm-svn: 42034

Preliminary implementation of UninitializedValues, which is based on
new solver (doesn't work yet, but compiles).

llvm-svn: 41970