hurd: unwinding support over signal trampolines

[thirdparty/binutils-gdb.git] / gdb / arch-utils.c

diff --git a/gdb/arch-utils.c b/gdb/arch-utils.c
index 2129c3b2c388670b6f52e85ba62a1370b9a1dad0..04955ea847b2eb93602b2bf82d2741284cd0912e 100644 (file)
--- a/gdb/arch-utils.c
+++ b/gdb/arch-utils.c
@@ -1,6 +1,6 @@
 /* Dynamic architecture support for GDB, the GNU debugger.
 
-   Copyright (C) 1998-2019 Free Software Foundation, Inc.
+   Copyright (C) 1998-2020 Free Software Foundation, Inc.
 
    This file is part of GDB.
 
@@ -858,7 +858,7 @@ default_return_in_first_hidden_param_p (struct gdbarch *gdbarch,
   /* Usually, the return value's address is stored the in the "first hidden"
      parameter if the return value should be passed by reference, as
      specified in ABI.  */
-  return language_pass_by_reference (type);
+  return !(language_pass_by_reference (type).trivially_copyable);
 }
 
 int default_insn_is_call (struct gdbarch *gdbarch, CORE_ADDR addr)
@@ -876,6 +876,38 @@ int default_insn_is_jump (struct gdbarch *gdbarch, CORE_ADDR addr)
   return 0;
 }
 
+/*  See arch-utils.h.  */
+
+bool
+default_program_breakpoint_here_p (struct gdbarch *gdbarch,
+                                  CORE_ADDR address)
+{
+  int len;
+  const gdb_byte *bpoint = gdbarch_breakpoint_from_pc (gdbarch, &address, &len);
+
+  /* Software breakpoints unsupported?  */
+  if (bpoint == nullptr)
+    return false;
+
+  gdb_byte *target_mem = (gdb_byte *) alloca (len);
+
+  /* Enable the automatic memory restoration from breakpoints while
+     we read the memory.  Otherwise we may find temporary breakpoints, ones
+     inserted by GDB, and flag them as permanent breakpoints.  */
+  scoped_restore restore_memory
+    = make_scoped_restore_show_memory_breakpoints (0);
+
+  if (target_read_memory (address, target_mem, len) == 0)
+    {
+      /* Check if this is a breakpoint instruction for this architecture,
+        including ones used by GDB.  */
+      if (memcmp (target_mem, bpoint, len) == 0)
+       return true;
+    }
+
+  return false;
+}
+
 void
 default_skip_permanent_breakpoint (struct regcache *regcache)
 {
@@ -1004,8 +1036,9 @@ default_get_pc_address_flags (frame_info *frame, CORE_ADDR pc)
   return "";
 }
 
+void _initialize_gdbarch_utils ();
 void
-_initialize_gdbarch_utils (void)
+_initialize_gdbarch_utils ()
 {
   add_setshow_enum_cmd ("endian", class_support,
                        endian_enum, &set_endian_string,