compiler: add src information to AST dumps (part 1 of 2).

    
    When emitting AST dumps, tag the end of selected statements with with
    source file and line number information where available. Example:
    
      tmp.76832448 = 0 // p.go:6
    
    Requires a corresponding change in gcc/go as well as this change to
    gofrontend.
    
    Reviewed-on: https://go-review.googlesource.com/29856

	* go-linemap.cc (Gcc_linemap::to_string): New method.

From-SVN: r240558

1 files changed, 28 insertions, 0 deletions

diff --git a/gcc/go/go-linemap.cc b/gcc/go/go-linemap.cc
index b41559e..b58a54b 100644
--- a/gcc/go/go-linemap.cc
+++ b/gcc/go/go-linemap.cc
@@ -29,6 +29,9 @@ class Gcc_linemap : public Linemap
   void
   stop();
 
+  std::string
+  to_string(Location);
+
  protected:
   Location
   get_predeclared_location();
@@ -60,6 +63,31 @@ Gcc_linemap::start_file(const char *file_name, unsigned line_begin)
   this->in_file_ = true;
 }
 
+// Stringify a location
+
+std::string
+Gcc_linemap::to_string(Location location)
+{
+  const line_map_ordinary *lmo;
+  source_location resolved_location;
+
+  // Screen out unknown and predeclared locations; produce output
+  // only for simple file:line locations.
+  resolved_location =
+      linemap_resolve_location (line_table, location.gcc_location(),
+                                LRK_SPELLING_LOCATION, &lmo);
+  if (lmo == NULL || resolved_location < RESERVED_LOCATION_COUNT)
+    return "";
+  const char *path = LINEMAP_FILE (lmo);
+  if (!path)
+    return "";
+
+  // Strip the source file down to the base file, to reduce clutter.
+  std::stringstream ss;
+  ss << lbasename(path) << ":" << SOURCE_LINE (lmo, location.gcc_location());
+  return ss.str();
+}
+
 // Stop getting locations.
 
 void