linux, dump_syms: Filter module entries outside specified ranges

Partitioned libraries generated with lld and llvm-objcopy currently
contain a superset of debug information, beyond what applies to the
library itself. This is because objcopy cannot split up debug
information by partition - instead, it places a copy of all debug
information into each partition.

In lieu of potential future support for lld or objcopy becoming able to
split up debug information, let dump_syms do the next best thing:

- Find the address ranges of all PT_LOAD segments in the lib.
- Supply these to the Module being generated.
- Filter additions to the Module based on these ranges.

Bug: 990190
Change-Id: Ib5f279f42e3f6ea79eed9665efbcc23c3c5d25dc
Reviewed-on: https://chromium-review.googlesource.com/c/breakpad/breakpad/+/1884699
Reviewed-by: Joshua Peraza <jperaza@chromium.org>

src/common/module.h

@@ -205,6 +205,14 @@ class Module {
   // Write is used.
   void SetLoadAddress(Address load_address);
 
+  // Sets address filtering on elements added to the module.  This allows
+  // libraries with extraneous debug symbols to generate symbol files containing
+  // only relevant symbols.  For example, an LLD-generated partition library may
+  // contain debug information pertaining to all partitions derived from a
+  // single "combined" library.  Filtering applies only to elements added after
+  // this method is called.
+  void SetAddressRanges(const vector<Range>& ranges);
+
   // Add FUNCTION to the module. FUNCTION's name must not be empty.
   // This module owns all Function objects added with this function:
   // destroying the module destroys them as well.
@@ -302,6 +310,10 @@ class Module {
   // if an error occurs, return false, and leave errno set.
   static bool WriteRuleMap(const RuleMap &rule_map, std::ostream &stream);
 
+  // Returns true of the specified address resides with an specified address
+  // range, or if no ranges have been specified.
+  bool AddressIsInModule(Address address) const;
+
   // Module header entries.
   string name_, os_, architecture_, id_, code_id_;
 
@@ -310,6 +322,10 @@ class Module {
   // address.
   Address load_address_;
 
+  // The set of valid address ranges of the module.  If specified, attempts to
+  // add elements residing outside these ranges will be silently filtered.
+  vector<Range> address_ranges_;
+
   // Relation for maps whose keys are strings shared with some other
   // structure.
   struct CompareStringPtrs {