From 2d9dae01fbfe04a12a8deff85ffb617d9d0b6638 Mon Sep 17 00:00:00 2001
From: Gabe Black <gabeblack@google.com>
Date: Wed, 3 Dec 2014 03:27:19 -0800
Subject: [PATCH] sim: Make it possible to override the breakpoint length
 check.

The check which makes sure the length of the breakpoint being written is the
same as a MachInst is only correct on fixed instruction width ISAs. Instead of
incorrectly applying that check to all ISAs, this change makes that the
default check and lets ISA specific GDB classes override it.
---
 src/base/remote_gdb.cc | 14 ++++++++++----
 src/base/remote_gdb.hh |  2 ++
 2 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/src/base/remote_gdb.cc b/src/base/remote_gdb.cc
index ead8db9ae..42b94b5f9 100644
--- a/src/base/remote_gdb.cc
+++ b/src/base/remote_gdb.cc
@@ -520,6 +520,12 @@ PCEventQueue *BaseRemoteGDB::getPcEventQueue()
     return &system->pcEventQueue;
 }
 
+bool
+BaseRemoteGDB::checkBpLen(size_t len)
+{
+    return len == sizeof(MachInst);
+}
+
 BaseRemoteGDB::HardBreakpoint::HardBreakpoint(BaseRemoteGDB *_gdb, Addr pc)
     : PCEvent(_gdb->getPcEventQueue(), "HardBreakpoint Event", pc),
       gdb(_gdb), refcount(0)
@@ -539,7 +545,7 @@ BaseRemoteGDB::HardBreakpoint::process(ThreadContext *tc)
 bool
 BaseRemoteGDB::insertSoftBreak(Addr addr, size_t len)
 {
-    if (len != sizeof(TheISA::MachInst))
+    if (!checkBpLen(len))
         panic("invalid length\n");
 
     return insertHardBreak(addr, len);
@@ -548,7 +554,7 @@ BaseRemoteGDB::insertSoftBreak(Addr addr, size_t len)
 bool
 BaseRemoteGDB::removeSoftBreak(Addr addr, size_t len)
 {
-    if (len != sizeof(MachInst))
+    if (!checkBpLen(len))
         panic("invalid length\n");
 
     return removeHardBreak(addr, len);
@@ -557,7 +563,7 @@ BaseRemoteGDB::removeSoftBreak(Addr addr, size_t len)
 bool
 BaseRemoteGDB::insertHardBreak(Addr addr, size_t len)
 {
-    if (len != sizeof(MachInst))
+    if (!checkBpLen(len))
         panic("invalid length\n");
 
     DPRINTF(GDBMisc, "inserting hardware breakpoint at %#x\n", addr);
@@ -574,7 +580,7 @@ BaseRemoteGDB::insertHardBreak(Addr addr, size_t len)
 bool
 BaseRemoteGDB::removeHardBreak(Addr addr, size_t len)
 {
-    if (len != sizeof(MachInst))
+    if (!checkBpLen(len))
         panic("invalid length\n");
 
     DPRINTF(GDBMisc, "removing hardware breakpoint at %#x\n", addr);
diff --git a/src/base/remote_gdb.hh b/src/base/remote_gdb.hh
index babf61049..8fab556f3 100644
--- a/src/base/remote_gdb.hh
+++ b/src/base/remote_gdb.hh
@@ -192,6 +192,8 @@ class BaseRemoteGDB
     PCEventQueue *getPcEventQueue();
 
   protected:
+    virtual bool checkBpLen(size_t len);
+
     class HardBreakpoint : public PCEvent
     {
       private:
-- 
2.30.2