Modified the notion of "Block-level expressions" in CFGs to include Stmt*. This
is because GNU-style Statement-expressions cause the last statement in the
statement-expression to act like an expression.
We now have two notions: block-level statements and block-level expressions.
The former are all Stmt* that appear in the list of statements in CFGBlocks. The
latter is the subset of the former; these block-level statements are used as
subexpressions somewhere in the AST. CFG::isBlockExpr() returns true for the
latter, not the former (previously isBlockExpr() always returned true for
non-Expr Stmt*).
Modified the LiveVariables analysis to also track liveness state for block-level
expressions (using the updated definition of block-level expressions).
Modified the dataflow solver so that when it records values for block-level
statements, it records the dataflow value *before* the transfer function for a
Stmt* is evaluated (not after). This is more in sync in what clients will want.
Modified CFGStmtVisitor to record the current block-level statement.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@46143
91177308-0d34-0410-b5e6-
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