cpu: add a condition-code register class

Add a third register class for condition codes,
in parallel with the integer and FP classes.
No ISAs use the CC class at this point though.

4 files changed, 18 insertions, 1 deletions

diff --git a/src/arch/power/insts/static_inst.cc b/src/arch/power/insts/static_inst.cc
index 09b662453..087e1f740 100644
--- a/src/arch/power/insts/static_inst.cc
+++ b/src/arch/power/insts/static_inst.cc
@@ -55,6 +55,8 @@ PowerStaticInst::printReg(std::ostream &os, int reg) const
           default: ccprintf(os, "unknown_reg");
             break;
         }
+      case CCRegClass:
+        panic("printReg: POWER does not implement CCRegClass\n");
     }
 }
 
diff --git a/src/arch/power/isa.hh b/src/arch/power/isa.hh
index 33439c48c..7b59b2ad1 100644
--- a/src/arch/power/isa.hh
+++ b/src/arch/power/isa.hh
@@ -98,6 +98,13 @@ class ISA : public SimObject
         return reg;
     }
 
+    // dummy
+    int
+    flattenCCIndex(int reg)
+    {
+        return reg;
+    }
+
     void startup(ThreadContext *tc) {}
 
     /// Explicitly import the otherwise hidden startup
diff --git a/src/arch/power/registers.hh b/src/arch/power/registers.hh
index 89de3719c..abee516fc 100644
--- a/src/arch/power/registers.hh
+++ b/src/arch/power/registers.hh
@@ -52,6 +52,9 @@ typedef uint64_t FloatRegBits;
 typedef double FloatReg;
 typedef uint64_t MiscReg;
 
+// dummy typedef since we don't have CC regs
+typedef uint8_t CCReg;
+
 // Constants Related to the number of registers
 const int NumIntArchRegs = 32;
 
@@ -64,6 +67,7 @@ const int NumInternalProcRegs = 0;
 
 const int NumIntRegs = NumIntArchRegs + NumIntSpecialRegs;
 const int NumFloatRegs = NumFloatArchRegs + NumFloatSpecialRegs;
+const int NumCCRegs = 0;
 const int NumMiscRegs = NUM_MISCREGS;
 
 // Semantically meaningful register indices
@@ -85,7 +89,8 @@ const int SyscallSuccessReg = 3;
 
 // These help enumerate all the registers for dependence tracking.
 const int FP_Reg_Base = NumIntRegs;
-const int Misc_Reg_Base = FP_Reg_Base + NumFloatRegs;
+const int CC_Reg_Base = FP_Reg_Base + NumFloatRegs;
+const int Misc_Reg_Base = CC_Reg_Base + NumCCRegs; // NumCCRegs == 0
 const int Max_Reg_Index = Misc_Reg_Base + NumMiscRegs;
 
 typedef union {
diff --git a/src/arch/power/utility.cc b/src/arch/power/utility.cc
index e3fa246fc..7be195b8d 100644
--- a/src/arch/power/utility.cc
+++ b/src/arch/power/utility.cc
@@ -48,6 +48,9 @@ copyRegs(ThreadContext *src, ThreadContext *dest)
     for (int i = 0; i < NumFloatRegs; ++i)
         dest->setFloatRegBits(i, src->readFloatRegBits(i));
 
+    // Would need to add condition-code regs if implemented
+    assert(NumCCRegs == 0);
+
     // Copy misc. registers
     copyMiscRegs(src, dest);