[analyzer] Add new PreImplicitCall and PostImplicitCall ProgramPoints.

These are currently unused, but are intended to be used in lieu of PreStmt
and PostStmt when the call is implicit (e.g. an automatic object destructor).

This also modifies the Data1 field of ProgramPoints to allow storing any
pointer-sized value, as opposed to only aligned pointers. This is necessary
to store SourceLocations.

There is currently no BugReporter support for these; they should be skipped
over in any diagnostic output.

This commit also tags checkers that currently rely on function calls only
occurring at StmtPoints.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@160019 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/StaticAnalyzer/Checkers/MallocChecker.cpp b/lib/StaticAnalyzer/Checkers/MallocChecker.cpp
index 41cd80e..8c2e529 100644
--- a/lib/StaticAnalyzer/Checkers/MallocChecker.cpp
+++ b/lib/StaticAnalyzer/Checkers/MallocChecker.cpp
@@ -1535,6 +1535,9 @@
   if (!S)
     return 0;
 
+  // FIXME: We will eventually need to handle non-statement-based events
+  // (__attribute__((cleanup))).
+
   // Find out if this is an interesting point and what is the kind.
   if (Mode == Normal) {
     if (isAllocated(RS, RSPrev, S)) {