[PATCH] Update source location for PRE inserted stmt

[Eric Botcazou]

> Those compiler generated statements do not have source origins, but
> they need to have debug location information attached so that
> information collected for them can be correlated with program
> constructs (such as CFG). One of the natural way is to use the source
> location associated with the program point where they are inserted.

No, there is nothing natural (and this can even be wrong).  The statements 
must have the source location corresponding to the source construct they are 
generated for, which may be totally different from that of the insertion 
point.  Yes, that can generate jumpiness in GDB, but this is far better that 
breaking the coverage info by giving the same source location to instructions 
that have different coverage status.

-- 
Eric Botcazou