arm: Fixes based on UBSan and static analysis

Another churn to clean up undefined behaviour, mostly ARM, but some
parts also touching the generic part of the code base.

Most of the fixes are simply ensuring that proper intialisation. One
of the more subtle changes is the return type of the sign-extension,
which is changed to uint64_t. This is to avoid shifting negative
values (undefined behaviour) in the ISA code.

4 files changed, 7 insertions, 5 deletions

diff --git a/src/cpu/o3/lsq_unit.hh b/src/cpu/o3/lsq_unit.hh
index f90f72ced..6fe832bf6 100644
--- a/src/cpu/o3/lsq_unit.hh
+++ b/src/cpu/o3/lsq_unit.hh
@@ -280,8 +280,9 @@ class LSQUnit {
       public:
         /** Default constructor. */
         LSQSenderState()
-            : mainPkt(NULL), pendingPacket(NULL), outstanding(1),
-              noWB(false), isSplit(false), pktToSend(false), cacheBlocked(false)
+            : mainPkt(NULL), pendingPacket(NULL), idx(0), outstanding(1),
+              isLoad(false), noWB(false), isSplit(false),
+              pktToSend(false), cacheBlocked(false)
           { }
 
         /** Instruction who initiated the access to memory. */
diff --git a/src/cpu/o3/rename_map.cc b/src/cpu/o3/rename_map.cc
index d816bf1fd..25289825c 100644
--- a/src/cpu/o3/rename_map.cc
+++ b/src/cpu/o3/rename_map.cc
@@ -39,7 +39,7 @@ using namespace std;
 /**** SimpleRenameMap methods ****/
 
 SimpleRenameMap::SimpleRenameMap()
-    : freeList(NULL)
+    : freeList(NULL), zeroReg(0)
 {
 }
 
diff --git a/src/cpu/o3/rename_map.hh b/src/cpu/o3/rename_map.hh
index 751c39f52..1aa3bc702 100644
--- a/src/cpu/o3/rename_map.hh
+++ b/src/cpu/o3/rename_map.hh
@@ -172,7 +172,7 @@ class UnifiedRenameMap
     typedef SimpleRenameMap::RenameInfo RenameInfo;
 
     /** Default constructor.  init() must be called prior to use. */
-    UnifiedRenameMap() {};
+    UnifiedRenameMap() : regFile(nullptr) {};
 
     /** Destructor. */
     ~UnifiedRenameMap() {};
diff --git a/src/cpu/o3/thread_state.hh b/src/cpu/o3/thread_state.hh
index 406c798f0..eea7a3d16 100644
--- a/src/cpu/o3/thread_state.hh
+++ b/src/cpu/o3/thread_state.hh
@@ -90,7 +90,8 @@ struct O3ThreadState : public ThreadState {
 
     O3ThreadState(O3CPU *_cpu, int _thread_num, Process *_process)
         : ThreadState(_cpu, _thread_num, _process),
-          cpu(_cpu), noSquashFromTC(false), trapPending(false)
+          cpu(_cpu), noSquashFromTC(false), trapPending(false),
+          tc(nullptr)
     {
         if (!FullSystem)
             return;