1 files changed, 278 insertions, 0 deletions
diff --git a/sim/common/sim-break.c b/sim/common/sim-break.c
new file mode 100644
index 00000000000..3b89560aeb1
--- /dev/null
+++ b/sim/common/sim-break.c
@@ -0,0 +1,278 @@
+/* Simulator breakpoint support.
+   Copyright (C) 1997 Free Software Foundation, Inc.
+   Contributed by Cygnus Support.
+
+This file is part of GDB, the GNU debugger.
+
+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 2, 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, write to the Free Software Foundation, Inc.,
+59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
+
+#include <stdio.h>
+
+#include "sim-main.h"
+#include "sim-assert.h"
+#include "sim-break.h"
+
+#ifndef SIM_BREAKPOINT
+#define SIM_BREAKPOINT {0x00}
+#define SIM_BREAKPOINT_SIZE (1)
+#endif
+
+struct
+sim_breakpoint
+{
+  struct sim_breakpoint *next;
+  SIM_ADDR addr;		/* Address of this breakpoint */
+  int flags;
+  unsigned char loc_contents[SIM_BREAKPOINT_SIZE]; /* Contents of addr while
+						      BP is enabled */
+};
+
+#define SIM_BREAK_INSERTED 0x1	/* Breakpoint has been inserted */
+#define SIM_BREAK_DISABLED 0x2	/* Breakpoint is disabled */
+
+static unsigned char sim_breakpoint [] = SIM_BREAKPOINT;
+
+static void insert_breakpoint PARAMS ((SIM_DESC sd,
+				       struct sim_breakpoint *bp));
+static void remove_breakpoint PARAMS ((SIM_DESC sd,
+				       struct sim_breakpoint *bp));
+static SIM_RC resume_handler PARAMS ((SIM_DESC sd));
+static SIM_RC suspend_handler PARAMS ((SIM_DESC sd));
+
+
+/* Do the actual work of inserting a breakpoint into the instruction
+   stream. */
+
+static void
+insert_breakpoint (sd, bp)
+     SIM_DESC sd;
+     struct sim_breakpoint *bp;
+{
+  if (bp->flags & (SIM_BREAK_INSERTED | SIM_BREAK_DISABLED))
+    return;
+
+  sim_core_read_buffer (sd, NULL, exec_map, bp->loc_contents,
+			bp->addr, SIM_BREAKPOINT_SIZE);
+  sim_core_write_buffer (sd, NULL, exec_map, sim_breakpoint,
+			 bp->addr, SIM_BREAKPOINT_SIZE);
+  bp->flags |= SIM_BREAK_INSERTED;
+}
+
+/* Do the actual work of removing a breakpoint. */
+
+static void
+remove_breakpoint (sd, bp)
+     SIM_DESC sd;
+     struct sim_breakpoint *bp;
+{
+  if (!(bp->flags & SIM_BREAK_INSERTED))
+    return;
+
+  sim_core_write_buffer (sd, NULL, exec_map, bp->loc_contents,
+			 bp->addr, SIM_BREAKPOINT_SIZE);
+  bp->flags &= ~SIM_BREAK_INSERTED;
+}
+
+/* Come here when a breakpoint insn is hit.  If it's really a breakpoint, we
+   halt things, and never return.  If it's a false hit, we return to let the
+   caller handle things.  */
+
+void
+sim_handle_breakpoint (sd, cpu, cia)
+     SIM_DESC sd;
+     sim_cpu *cpu;
+     sim_cia cia;
+{
+  struct sim_breakpoint *bp;
+
+  for (bp = STATE_BREAKPOINTS (sd); bp; bp = bp->next)
+    if (bp->addr == CIA_ADDR (cia))
+      break;
+
+  if (!bp || !(bp->flags & SIM_BREAK_INSERTED))
+    return;
+
+  sim_engine_halt (sd, STATE_CPU (sd, 0), NULL, cia, sim_stopped, SIM_SIGTRAP);
+}
+
+/* Handler functions for simulator resume and suspend events. */
+
+static SIM_RC
+resume_handler (sd)
+     SIM_DESC sd;
+{
+  struct sim_breakpoint *bp;
+
+  for (bp = STATE_BREAKPOINTS (sd); bp; bp = bp->next)
+    insert_breakpoint (sd, bp);
+
+  return SIM_RC_OK;
+}
+
+static SIM_RC
+suspend_handler (sd)
+     SIM_DESC sd;
+{
+  struct sim_breakpoint *bp;
+
+  for (bp = STATE_BREAKPOINTS (sd); bp; bp = bp->next)
+    remove_breakpoint (sd, bp);
+
+  return SIM_RC_OK;
+}
+
+/* Called from simulator module initialization.  */
+
+SIM_RC
+sim_break_install (sd)
+     SIM_DESC sd;
+{
+  sim_module_add_resume_fn (sd, resume_handler);
+  sim_module_add_suspend_fn (sd, suspend_handler);
+
+  return SIM_RC_OK;
+}
+
+/* Install a breakpoint.  This is a user-function.  The breakpoint isn't
+   actually installed here.  We just record it.  Resume_handler does the
+   actual work.
+*/
+
+SIM_RC
+sim_set_breakpoint (sd, addr)
+     SIM_DESC sd;
+     SIM_ADDR addr;
+{
+  struct sim_breakpoint *bp;
+
+  for (bp = STATE_BREAKPOINTS (sd); bp; bp = bp->next)
+    if (bp->addr == addr)
+      return SIM_RC_DUPLICATE_BREAKPOINT; /* Already there */
+    else
+      break; /* FIXME: why not scan all bp's? */
+
+  bp = ZALLOC (struct sim_breakpoint);
+
+  bp->addr = addr;
+  bp->next = STATE_BREAKPOINTS (sd);
+  bp->flags = 0;
+  STATE_BREAKPOINTS (sd) = bp;
+
+  return SIM_RC_OK;
+}
+
+/* Delete a breakpoint.  All knowlege of the breakpoint is removed from the
+   simulator.
+*/
+
+SIM_RC
+sim_clear_breakpoint (sd, addr)
+     SIM_DESC sd;
+     SIM_ADDR addr;
+{
+  struct sim_breakpoint *bp, *bpprev;
+
+  for (bp = STATE_BREAKPOINTS (sd), bpprev = NULL;
+       bp;
+       bpprev = bp, bp = bp->next)
+    if (bp->addr == addr)
+      break;
+
+  if (!bp)
+    return SIM_RC_UNKNOWN_BREAKPOINT;
+
+  remove_breakpoint (sd, bp);
+
+  if (bpprev)
+    bpprev->next = bp->next;
+  else
+    STATE_BREAKPOINTS (sd) = NULL;
+
+  zfree (bp);
+
+  return SIM_RC_OK;
+}
+
+SIM_RC
+sim_clear_all_breakpoints (sd)
+     SIM_DESC sd;
+{
+  while (STATE_BREAKPOINTS (sd))
+    sim_clear_breakpoint (sd, STATE_BREAKPOINTS (sd)->addr);
+
+  return SIM_RC_OK;
+}
+
+SIM_RC
+sim_enable_breakpoint (sd, addr)
+     SIM_DESC sd;
+     SIM_ADDR addr;
+{
+  struct sim_breakpoint *bp;
+
+  for (bp = STATE_BREAKPOINTS (sd); bp; bp = bp->next)
+    if (bp->addr == addr)
+      break;
+
+  if (!bp)
+    return SIM_RC_UNKNOWN_BREAKPOINT;
+
+  bp->flags &= ~SIM_BREAK_DISABLED;
+
+  return SIM_RC_OK;
+}
+
+SIM_RC
+sim_disable_breakpoint (sd, addr)
+     SIM_DESC sd;
+     SIM_ADDR addr;
+{
+  struct sim_breakpoint *bp;
+
+  for (bp = STATE_BREAKPOINTS (sd); bp; bp = bp->next)
+    if (bp->addr == addr)
+      break;
+
+  if (!bp)
+    return SIM_RC_UNKNOWN_BREAKPOINT;
+
+  bp->flags |= SIM_BREAK_DISABLED;
+
+  return SIM_RC_OK;
+}
+
+SIM_RC
+sim_enable_all_breakpoints (sd)
+     SIM_DESC sd;
+{
+  struct sim_breakpoint *bp;
+
+  for (bp = STATE_BREAKPOINTS (sd); bp; bp = bp->next)
+    bp->flags &= ~SIM_BREAK_DISABLED;
+
+  return SIM_RC_OK;
+}
+
+SIM_RC
+sim_disable_all_breakpoints (sd)
+     SIM_DESC sd;
+{
+  struct sim_breakpoint *bp;
+
+  for (bp = STATE_BREAKPOINTS (sd); bp; bp = bp->next)
+    bp->flags |= SIM_BREAK_DISABLED;
+
+  return SIM_RC_OK;
+}