New file (interfaces to dg.exp).

gas/testsuite/lib/.Sanitize

@@ -27,6 +27,7 @@ Do-first:
 Things-to-keep:
 
 gas-defs.exp
+gas-dg.exp
 doboth
 doobjcmp
 dostriptest

gas/testsuite/lib/gas-dg.exp

@@ -0,0 +1,43 @@
+# Define gas callbacks for dg.exp.
+
+load_lib dg.exp
+
+# The use of this function is still in a bit of flux.
+# It should be theoretically possible to assemble, link, and run a file
+# but we currently don't support that.  Assembler testcases aren't usually
+# that elaborate anyway.  :-)
+
+proc gas-dg-test { prog do_what tool_flags default_tool_flags libs } {
+    switch $do_what {
+	"preprocess" {
+	}
+	"assemble" {
+	}
+	"link" {
+	}
+	"run" {
+	}
+    }
+
+    # gas_start prepends $srcdir/$subdir so we must remove it from PROG
+    # if present.  First remove extraneous //'s.
+    global srcdir subdir
+    set dir "$srcdir/$subdir"
+    regsub -all "//" $dir "/" dir
+    regsub -all "//" $prog "/" prog
+    if [string match "$dir/*" $prog] {
+	regsub "$dir" $prog "" prog
+    }
+
+    # FIXME: This should be gas_start but it doesn't set comp_output.
+    gas_run $prog $tool_flags ""
+}
+
+proc gas-dg-prune { system text } {
+    #send_user "Before:$text\n"
+    regsub -all "(^|\n)\[^\n\]*: Assembler messages:\[^\n\]*" $text "" text
+    regsub -all "(^|\n)\[^\n\]*: End of file not at end\[^\n\]*Newline inserted." $text "" text
+    #send_user "After:$text\n"
+
+    return $text
+}