Add symbol, line, and location to DAP disassemble result

The DAP spec allows a number of attributes on the resulting
instructions that gdb currently does not emit.  A user requested some
of these, so this patch adds the 'symbol', 'line', and 'location'
attributes.  While the spec lets the implementation omit 'location' in
some cases, it was simpler in the code to just always emit it, as then
no extra tracking was needed.

2 files changed, 157 insertions, 0 deletions

diff --git a/gdb/testsuite/gdb.dap/disassem.c b/gdb/testsuite/gdb.dap/disassem.c
new file mode 100644
index 0000000..c0f5128
--- /dev/null
+++ b/gdb/testsuite/gdb.dap/disassem.c
@@ -0,0 +1,52 @@
+/* Copyright 2024 Free Software Foundation, Inc.
+
+   This file is part of GDB.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+__attribute__((__noinline__)) static int
+callee (int x)
+{
+  return x * 2;
+}
+
+static inline int __attribute__((__always_inline__))
+compute (int x)
+{
+  return callee (x);
+}
+
+static int
+return_value (int x)
+{
+  int accum = 0;
+
+  for (int i = 0; i < x; ++i)
+    {
+      int value = compute (i);
+      if (value < 0)
+	goto out_label;
+    }
+
+ out_label:
+
+  return accum;
+}
+
+int
+main ()
+{
+  int value = return_value (23);
+  return value > 0 ? 0 : 1;
+}
diff --git a/gdb/testsuite/gdb.dap/disassem.exp b/gdb/testsuite/gdb.dap/disassem.exp
new file mode 100644
index 0000000..87fb516
--- /dev/null
+++ b/gdb/testsuite/gdb.dap/disassem.exp
@@ -0,0 +1,105 @@
+# Copyright 2024 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# Test DAP disassembly.
+
+require allow_dap_tests
+
+load_lib dap-support.exp
+
+standard_testfile
+
+if {[build_executable ${testfile}.exp $testfile] == -1} {
+    return
+}
+
+if {[dap_initialize] == ""} {
+    return
+}
+
+set obj [dap_check_request_and_response "set breakpoint" \
+	     setFunctionBreakpoints \
+	     {o breakpoints [a [o name [s main]]]}]
+set fn_bpno [dap_get_breakpoint_number $obj]
+
+dap_check_request_and_response "configurationDone" configurationDone
+
+if {[dap_launch $testfile] == ""} {
+    return
+}
+dap_wait_for_event_and_check "inferior started" thread "body reason" started
+
+dap_wait_for_event_and_check "stopped at line breakpoint" stopped \
+    "body reason" breakpoint \
+    "body hitBreakpointIds" $fn_bpno
+
+# Find out how many lines of disassembly we should request.  This is
+# kind of lame but DAP doesn't really provide tools to do this, and
+# gdb's DAP implementation doesn't try to figure out what memory might
+# not really be part of a function.
+set obj [dap_check_request_and_response "disassemble using CLI" \
+	     evaluate {o expression [s {disassemble &return_value}] \
+			   context [s repl]}]
+set output [dict get [lindex $obj 0] body result]
+# The result will have literal "\" "n" sequences, turn these into
+# newlines.
+set with_nl [string map [list "\\n" "\n"] $output]
+# The value we want is the number of lines starting with an address.
+set insn_count 0
+foreach line [split $with_nl "\n"] {
+    if {[regexp "^ *0x" $line]} {
+	incr insn_count
+    }
+}
+
+set obj [dap_check_request_and_response "find function address" \
+	     evaluate {o expression [s "&return_value"]}]
+set pc [dict get [lindex $obj 0] body memoryReference]
+
+set obj [dap_check_request_and_response "disassemble the function" \
+	     disassemble \
+	     [format {o memoryReference [s %s] instructionCount [i %d]} \
+		  $pc $insn_count]]
+set response [lindex $obj 0]
+
+set seen_labels(_) _
+set insn_no 1
+foreach insn [dict get $response body instructions] {
+    with_test_prefix $insn_no {
+	gdb_assert {[dict exists $insn line]} \
+	    "line in disassemble output"
+	gdb_assert {[dict exists $insn location]} \
+	    "location in disassemble output"
+	if {[dict exists $insn symbol]} {
+	    set seen_labels([dict get $insn symbol]) 1
+	}
+    }
+    incr insn_no
+}
+
+proc require_label {name} {
+    global seen_labels
+    if {[info exists seen_labels($name)]} {
+	pass "saw label $name"
+    } else {
+	fail "saw label $name"
+    }
+}
+
+require_label return_value
+require_label compute
+require_label out_label
+
+dap_shutdown