arch: Use const StaticInstPtr references where possible

This patch optimises the passing of StaticInstPtr by avoiding copying
the reference-counting pointer. This avoids first incrementing and
then decrementing the reference-counting pointer.

4 files changed, 11 insertions, 9 deletions

diff --git a/src/cpu/o3/cpu.cc b/src/cpu/o3/cpu.cc
index 7ed3944cf..925b3d2d8 100644
--- a/src/cpu/o3/cpu.cc
+++ b/src/cpu/o3/cpu.cc
@@ -946,12 +946,13 @@ FullO3CPU<Impl>::processInterrupts(const Fault &interrupt)
     this->interrupts->updateIntrInfo(this->threadContexts[0]);
 
     DPRINTF(O3CPU, "Interrupt %s being handled\n", interrupt->name());
-    this->trap(interrupt, 0, NULL);
+    this->trap(interrupt, 0, nullptr);
 }
 
 template <class Impl>
 void
-FullO3CPU<Impl>::trap(const Fault &fault, ThreadID tid, StaticInstPtr inst)
+FullO3CPU<Impl>::trap(const Fault &fault, ThreadID tid,
+                      const StaticInstPtr &inst)
 {
     // Pass the thread's TC into the invoke method.
     fault->invoke(this->threadContexts[tid], inst);
diff --git a/src/cpu/o3/cpu.hh b/src/cpu/o3/cpu.hh
index c263790ce..96cd071e4 100644
--- a/src/cpu/o3/cpu.hh
+++ b/src/cpu/o3/cpu.hh
@@ -376,7 +376,7 @@ class FullO3CPU : public BaseO3CPU
     { return globalSeqNum++; }
 
     /** Traps to handle given fault. */
-    void trap(const Fault &fault, ThreadID tid, StaticInstPtr inst);
+    void trap(const Fault &fault, ThreadID tid, const StaticInstPtr &inst);
 
     /** HW return from error interrupt. */
     Fault hwrei(ThreadID tid);
diff --git a/src/cpu/o3/dyn_inst.hh b/src/cpu/o3/dyn_inst.hh
index ea961092d..80d502f0e 100644
--- a/src/cpu/o3/dyn_inst.hh
+++ b/src/cpu/o3/dyn_inst.hh
@@ -83,12 +83,13 @@ class BaseO3DynInst : public BaseDynInst<Impl>
 
   public:
     /** BaseDynInst constructor given a binary instruction. */
-    BaseO3DynInst(StaticInstPtr staticInst, StaticInstPtr macroop,
+    BaseO3DynInst(const StaticInstPtr &staticInst, const StaticInstPtr &macroop,
                   TheISA::PCState pc, TheISA::PCState predPC,
                   InstSeqNum seq_num, O3CPU *cpu);
 
     /** BaseDynInst constructor given a static inst pointer. */
-    BaseO3DynInst(StaticInstPtr _staticInst, StaticInstPtr _macroop);
+    BaseO3DynInst(const StaticInstPtr &_staticInst,
+                  const StaticInstPtr &_macroop);
 
     ~BaseO3DynInst();
 
diff --git a/src/cpu/o3/dyn_inst_impl.hh b/src/cpu/o3/dyn_inst_impl.hh
index e51054f8d..fa3ce28fa 100644
--- a/src/cpu/o3/dyn_inst_impl.hh
+++ b/src/cpu/o3/dyn_inst_impl.hh
@@ -49,8 +49,8 @@
 #include "debug/O3PipeView.hh"
 
 template <class Impl>
-BaseO3DynInst<Impl>::BaseO3DynInst(StaticInstPtr staticInst,
-                                   StaticInstPtr macroop,
+BaseO3DynInst<Impl>::BaseO3DynInst(const StaticInstPtr &staticInst,
+                                   const StaticInstPtr &macroop,
                                    TheISA::PCState pc, TheISA::PCState predPC,
                                    InstSeqNum seq_num, O3CPU *cpu)
     : BaseDynInst<Impl>(staticInst, macroop, pc, predPC, seq_num, cpu)
@@ -59,8 +59,8 @@ BaseO3DynInst<Impl>::BaseO3DynInst(StaticInstPtr staticInst,
 }
 
 template <class Impl>
-BaseO3DynInst<Impl>::BaseO3DynInst(StaticInstPtr _staticInst,
-                                   StaticInstPtr _macroop)
+BaseO3DynInst<Impl>::BaseO3DynInst(const StaticInstPtr &_staticInst,
+                                   const StaticInstPtr &_macroop)
     : BaseDynInst<Impl>(_staticInst, _macroop)
 {
     initVars();