Changes to support automatic renaming of the shadow registers at decode time. This requires using an ExtMachInst (uint64_t) instead of the normal MachInst; the ExtMachInst is packed with extra decode context information. In the case of Alpha, the PAL mode is included.

The shadow registers are folded into the normal integer registers to ease renaming indexing.

Include the removed Opcdec class of instructions for faulting when a pal mode only instruction is decoded in non-pal mode.

arch/alpha/ev5.cc:
    Changes to automatically map the shadow registers if the instruction is in PAL mode.
arch/alpha/isa/branch.isa:
arch/alpha/isa/decoder.isa:
arch/alpha/isa/fp.isa:
arch/alpha/isa/int.isa:
arch/alpha/isa/mem.isa:
arch/alpha/isa/pal.isa:
arch/alpha/isa/unimp.isa:
    Changes for automatically using the shadow registers.  Now instructions must decode based on an ExtMachInst, which is a MachInst with any decode context information concatenated onto the higher order bits.
arch/alpha/isa/main.isa:
    Changes for automatically using the shadow registers.  Now instructions must decode based on an ExtMachInst, which is a MachInst with any decode context information concatenated onto the higher order bits.

    The decoder (for Alpha) uses the 32nd bit in order to determine if the machine is in PAL mode.  If it is, then it refers to the reg_redir table to determine the true index of the register it is using.

    Also include the opcdec instruction definition.
arch/alpha/isa_traits.hh:
    Define ExtMachInst type that is used by the static inst in order to decode the instruction, given the context of being in pal mode or not.

    Redefine the number of Int registers, splitting it into NumIntArchRegs (32) and NumIntRegs (32 + 8 shadow registers).

    Change the dependence tags to reflect the integer registers include the 8 shadow registers.

    Define function to make an ExtMachInst.  Currently it is somewhat specific to Alpha; in the future it must be decided to make this more generic and possibly slower, or leave it specific to each architecture and ifdef it within the CPU.
arch/isa_parser.py:
    Have static insts decode on the ExtMachInst.
base/remote_gdb.cc:
    Support the automatic remapping of shadow registers.  Remote GDB must now look at the PC being read in order to tell if it should use the normal register indices or the shadow register indices.
cpu/o3/regfile.hh:
    Comment out the pal registers; they are now a part of the integer registers.
cpu/simple/cpu.cc:
    Create an ExtMachInst to decode on, based on the normal MachInst and the PC of the instructoin.
cpu/static_inst.hh:
    Change from MachInst to ExtMachInst to support shadow register renaming.

--HG--
extra : convert_revision : 1d23eabf735e297068e1917445a6348e9f8c88d5

16 files changed, 225 insertions, 128 deletions

diff --git a/arch/alpha/ev5.cc b/arch/alpha/ev5.cc
index 2bb005eb4..9193e40f0 100644
--- a/arch/alpha/ev5.cc
+++ b/arch/alpha/ev5.cc
@@ -46,35 +46,12 @@ using namespace EV5;
 
 ////////////////////////////////////////////////////////////////////////
 //
-//
-//
-void
-AlphaISA::swap_palshadow(RegFile *regs, bool use_shadow)
-{
-    if (regs->pal_shadow == use_shadow)
-        panic("swap_palshadow: wrong PAL shadow state");
-
-    regs->pal_shadow = use_shadow;
-
-    for (int i = 0; i < NumIntRegs; i++) {
-        if (reg_redir[i]) {
-            IntReg temp = regs->intRegFile[i];
-            regs->intRegFile[i] = regs->palregs[i];
-            regs->palregs[i] = temp;
-        }
-    }
-}
-
-////////////////////////////////////////////////////////////////////////
-//
 //  Machine dependent functions
 //
 void
 AlphaISA::initCPU(RegFile *regs, int cpuId)
 {
     initIPRs(&regs->miscRegs, cpuId);
-    // CPU comes up with PAL regs enabled
-    swap_palshadow(regs, true);
 
     regs->intRegFile[16] = cpuId;
     regs->intRegFile[0] = cpuId;
@@ -83,12 +60,6 @@ AlphaISA::initCPU(RegFile *regs, int cpuId)
     regs->npc = regs->pc + sizeof(MachInst);
 }
 
-const int AlphaISA::reg_redir[AlphaISA::NumIntRegs] = {
-    /*  0 */ 0, 0, 0, 0, 0, 0, 0, 0,
-    /*  8 */ 1, 1, 1, 1, 1, 1, 1, 0,
-    /* 16 */ 0, 0, 0, 0, 0, 0, 0, 0,
-    /* 24 */ 0, 1, 0, 0, 0, 0, 0, 0 };
-
 ////////////////////////////////////////////////////////////////////////
 //
 //
@@ -186,9 +157,6 @@ ExecContext::ev5_temp_trap(Fault fault)
                    readMiscReg(AlphaISA::IPR_EXC_ADDR) + 4);
     }
 
-    if (!inPalMode())
-        AlphaISA::swap_palshadow(&regs, true);
-
     regs.pc = readMiscReg(AlphaISA::IPR_PAL_BASE) +
         (dynamic_cast<AlphaFault *>(fault.get()))->vect();
     regs.npc = regs.pc + sizeof(MachInst);
@@ -233,9 +201,6 @@ ExecContext::hwrei()
     if (!misspeculating()) {
         kernelStats->hwrei();
 
-        if ((readMiscReg(AlphaISA::IPR_EXC_ADDR) & 1) == 0)
-            AlphaISA::swap_palshadow(&regs, false);
-
         cpu->checkInterrupts = true;
     }
 
diff --git a/arch/alpha/isa/branch.isa b/arch/alpha/isa/branch.isa
index 9a7fb9d79..b528df938 100644
--- a/arch/alpha/isa/branch.isa
+++ b/arch/alpha/isa/branch.isa
@@ -46,7 +46,7 @@ output header {{
         mutable const SymbolTable *cachedSymtab;
 
         /// Constructor
-        PCDependentDisassembly(const char *mnem, MachInst _machInst,
+        PCDependentDisassembly(const char *mnem, ExtMachInst _machInst,
                                OpClass __opClass)
             : AlphaStaticInst(mnem, _machInst, __opClass),
               cachedPC(0), cachedSymtab(0)
@@ -68,7 +68,7 @@ output header {{
         int32_t disp;
 
         /// Constructor.
-        Branch(const char *mnem, MachInst _machInst, OpClass __opClass)
+        Branch(const char *mnem, ExtMachInst _machInst, OpClass __opClass)
             : PCDependentDisassembly(mnem, _machInst, __opClass),
               disp(BRDISP << 2)
         {
@@ -93,7 +93,7 @@ output header {{
 
       public:
         /// Constructor
-        Jump(const char *mnem, MachInst _machInst, OpClass __opClass)
+        Jump(const char *mnem, ExtMachInst _machInst, OpClass __opClass)
             : PCDependentDisassembly(mnem, _machInst, __opClass),
               disp(BRDISP)
         {
diff --git a/arch/alpha/isa/decoder.isa b/arch/alpha/isa/decoder.isa
index ca38dca92..ea858dd7d 100644
--- a/arch/alpha/isa/decoder.isa
+++ b/arch/alpha/isa/decoder.isa
@@ -681,7 +681,6 @@ decode OPCODE default Unknown::unknown() {
             bool dopal = xc->simPalCheck(palFunc);
 
             if (dopal) {
-                AlphaISA::swap_palshadow(&xc->xcBase()->regs, true);
                 xc->setMiscRegWithEffect(AlphaISA::IPR_EXC_ADDR, NPC);
                 NPC = xc->readMiscRegWithEffect(AlphaISA::IPR_PAL_BASE, fault) + palOffset;
             }
@@ -705,50 +704,56 @@ decode OPCODE default Unknown::unknown() {
 #endif
 
 #if FULL_SYSTEM
-    format HwLoad {
-        0x1b: decode HW_LDST_QUAD {
-            0: hw_ld({{ EA = (Rb + disp) & ~3; }}, {{ Ra = Mem.ul; }}, L);
-            1: hw_ld({{ EA = (Rb + disp) & ~7; }}, {{ Ra = Mem.uq; }}, Q);
+    0x1b: decode PALMODE {
+        0: OpcdecFault::hw_st_quad();
+        1: decode HW_LDST_QUAD {
+            format HwLoad {
+                0: hw_ld({{ EA = (Rb + disp) & ~3; }}, {{ Ra = Mem.ul; }}, L);
+                1: hw_ld({{ EA = (Rb + disp) & ~7; }}, {{ Ra = Mem.uq; }}, Q);
+            }
         }
     }
 
-    format HwStore {
-        0x1f: decode HW_LDST_COND {
-            0: decode HW_LDST_QUAD {
-                0: hw_st({{ EA = (Rb + disp) & ~3; }},
-                         {{ Mem.ul = Ra<31:0>; }}, L);
-                1: hw_st({{ EA = (Rb + disp) & ~7; }},
-                         {{ Mem.uq = Ra.uq; }}, Q);
-            }
+    0x1f: decode PALMODE {
+        0: OpcdecFault::hw_st_cond();
+        format HwStore {
+            1: decode HW_LDST_COND {
+                0: decode HW_LDST_QUAD {
+                    0: hw_st({{ EA = (Rb + disp) & ~3; }},
+                {{ Mem.ul = Ra<31:0>; }}, L);
+                    1: hw_st({{ EA = (Rb + disp) & ~7; }},
+                {{ Mem.uq = Ra.uq; }}, Q);
+                }
 
-            1: FailUnimpl::hw_st_cond();
+                1: FailUnimpl::hw_st_cond();
+            }
         }
     }
 
-    format HwMoveIPR {
-        0x19: hw_mfpr({{
-            // this instruction is only valid in PAL mode
-            if (!xc->inPalMode()) {
-                fault = new UnimplementedOpcodeFault;
-            }
-            else {
+    0x19: decode PALMODE {
+        0: OpcdecFault::hw_mfpr();
+        format HwMoveIPR {
+            1: hw_mfpr({{
                 Ra = xc->readMiscRegWithEffect(ipr_index, fault);
-            }
-        }});
-        0x1d: hw_mtpr({{
-            // this instruction is only valid in PAL mode
-            if (!xc->inPalMode()) {
-                fault = new UnimplementedOpcodeFault;
-            }
-            else {
+            }});
+        }
+    }
+
+    0x1d: decode PALMODE {
+        0: OpcdecFault::hw_mtpr();
+        format HwMoveIPR {
+            1: hw_mtpr({{
                 xc->setMiscRegWithEffect(ipr_index, Ra);
                 if (traceData) { traceData->setData(Ra); }
-            }
-        }});
+            }});
+        }
     }
 
     format BasicOperate {
-        0x1e: hw_rei({{ xc->hwrei(); }}, IsSerializing);
+        0x1e: decode PALMODE {
+            0: OpcdecFault::hw_rei();
+            1:hw_rei({{ xc->hwrei(); }}, IsSerializing);
+        }
 
         // M5 special opcodes use the reserved 0x01 opcode space
         0x01: decode M5FUNC {
diff --git a/arch/alpha/isa/fp.isa b/arch/alpha/isa/fp.isa
index 13656359f..f34c13c42 100644
--- a/arch/alpha/isa/fp.isa
+++ b/arch/alpha/isa/fp.isa
@@ -106,7 +106,7 @@ output header {{
         mutable bool warnedOnTrapping;
 
         /// Constructor
-        AlphaFP(const char *mnem, MachInst _machInst, OpClass __opClass)
+        AlphaFP(const char *mnem, ExtMachInst _machInst, OpClass __opClass)
             : AlphaStaticInst(mnem, _machInst, __opClass),
               roundingMode((enum RoundingMode)FP_ROUNDMODE),
               trappingMode((enum TrappingMode)FP_TRAPMODE),
diff --git a/arch/alpha/isa/int.isa b/arch/alpha/isa/int.isa
index 049437f8c..17ecc1a51 100644
--- a/arch/alpha/isa/int.isa
+++ b/arch/alpha/isa/int.isa
@@ -37,7 +37,7 @@ output header {{
         uint8_t imm;
 
         /// Constructor
-        IntegerImm(const char *mnem, MachInst _machInst, OpClass __opClass)
+        IntegerImm(const char *mnem, ExtMachInst _machInst, OpClass __opClass)
             : AlphaStaticInst(mnem, _machInst, __opClass), imm(INTIMM)
         {
         }
diff --git a/arch/alpha/isa/main.isa b/arch/alpha/isa/main.isa
index ad9c2a55e..17c9989ab 100644
--- a/arch/alpha/isa/main.isa
+++ b/arch/alpha/isa/main.isa
@@ -79,6 +79,7 @@ namespace AlphaISA;
 //
 
 // Universal (format-independent) fields
+def bitfield PALMODE    <32:32>;
 def bitfield OPCODE	<31:26>;
 def bitfield RA		<25:21>;
 def bitfield RB		<20:16>;
@@ -153,9 +154,12 @@ def operands {{
     # Int regs default to unsigned, but code should not count on this.
     # For clarity, descriptions that depend on unsigned behavior should
     # explicitly specify '.uq'.
-    'Ra': ('IntReg', 'uq', 'RA', 'IsInteger', 1),
-    'Rb': ('IntReg', 'uq', 'RB', 'IsInteger', 2),
-    'Rc': ('IntReg', 'uq', 'RC', 'IsInteger', 3),
+    'Ra': ('IntReg', 'uq', 'PALMODE ? AlphaISA::reg_redir[RA] : RA',
+           'IsInteger', 1),
+    'Rb': ('IntReg', 'uq', 'PALMODE ? AlphaISA::reg_redir[RB] : RB',
+           'IsInteger', 2),
+    'Rc': ('IntReg', 'uq', 'PALMODE ? AlphaISA::reg_redir[RC] : RC',
+           'IsInteger', 3),
     'Fa': ('FloatReg', 'df', 'FA', 'IsFloating', 1),
     'Fb': ('FloatReg', 'df', 'FB', 'IsFloating', 2),
     'Fc': ('FloatReg', 'df', 'FC', 'IsFloating', 3),
@@ -200,7 +204,7 @@ output header {{
         };
 
         /// Constructor.
-        AlphaStaticInst(const char *mnem, MachInst _machInst,
+        AlphaStaticInst(const char *mnem, ExtMachInst _machInst,
                         OpClass __opClass)
             : StaticInst(mnem, _machInst, __opClass)
         {
@@ -272,7 +276,7 @@ def template BasicDeclare {{
     {
       public:
         /// Constructor.
-        %(class_name)s(MachInst machInst);
+        %(class_name)s(ExtMachInst machInst);
 
         %(BasicExecDeclare)s
     };
@@ -280,7 +284,7 @@ def template BasicDeclare {{
 
 // Basic instruction class constructor template.
 def template BasicConstructor {{
-    inline %(class_name)s::%(class_name)s(MachInst machInst)
+    inline %(class_name)s::%(class_name)s(ExtMachInst machInst)
          : %(base_class)s("%(mnemonic)s", machInst, %(op_class)s)
     {
         %(constructor)s;
@@ -344,7 +348,7 @@ output header {{
 
       public:
         /// Constructor
-        Nop(const std::string _originalDisassembly, MachInst _machInst)
+        Nop(const std::string _originalDisassembly, ExtMachInst _machInst)
             : AlphaStaticInst("nop", _machInst, No_OpClass),
               originalDisassembly(_originalDisassembly)
         {
@@ -428,6 +432,9 @@ def format BasicOperateWithNopCheck(code, *opt_args) {{
 // PAL instruction templates, formats, etc.
 ##include "m5/arch/alpha/isa/pal.isa"
 
+// Opcdec fault instruction templates, formats, etc.
+##include "m5/arch/alpha/isa/opcdec.isa"
+
 // Unimplemented instruction templates, formats, etc.
 ##include "m5/arch/alpha/isa/unimp.isa"
 
diff --git a/arch/alpha/isa/mem.isa b/arch/alpha/isa/mem.isa
index 61d6ea8fa..3c8b4f755 100644
--- a/arch/alpha/isa/mem.isa
+++ b/arch/alpha/isa/mem.isa
@@ -42,7 +42,7 @@ output header {{
         const StaticInstPtr memAccPtr;
 
         /// Constructor
-        Memory(const char *mnem, MachInst _machInst, OpClass __opClass,
+        Memory(const char *mnem, ExtMachInst _machInst, OpClass __opClass,
                StaticInstPtr _eaCompPtr = nullStaticInstPtr,
                StaticInstPtr _memAccPtr = nullStaticInstPtr)
             : AlphaStaticInst(mnem, _machInst, __opClass),
@@ -70,7 +70,7 @@ output header {{
         int32_t disp;
 
         /// Constructor.
-        MemoryDisp32(const char *mnem, MachInst _machInst, OpClass __opClass,
+        MemoryDisp32(const char *mnem, ExtMachInst _machInst, OpClass __opClass,
                      StaticInstPtr _eaCompPtr = nullStaticInstPtr,
                      StaticInstPtr _memAccPtr = nullStaticInstPtr)
             : Memory(mnem, _machInst, __opClass, _eaCompPtr, _memAccPtr),
@@ -89,7 +89,7 @@ output header {{
     {
       protected:
         /// Constructor
-        MemoryNoDisp(const char *mnem, MachInst _machInst, OpClass __opClass,
+        MemoryNoDisp(const char *mnem, ExtMachInst _machInst, OpClass __opClass,
                      StaticInstPtr _eaCompPtr = nullStaticInstPtr,
                      StaticInstPtr _memAccPtr = nullStaticInstPtr)
             : Memory(mnem, _machInst, __opClass, _eaCompPtr, _memAccPtr)
@@ -141,7 +141,7 @@ def template LoadStoreDeclare {{
         {
           public:
             /// Constructor
-            EAComp(MachInst machInst);
+            EAComp(ExtMachInst machInst);
 
             %(BasicExecDeclare)s
         };
@@ -153,7 +153,7 @@ def template LoadStoreDeclare {{
         {
           public:
             /// Constructor
-            MemAcc(MachInst machInst);
+            MemAcc(ExtMachInst machInst);
 
             %(BasicExecDeclare)s
         };
@@ -161,7 +161,7 @@ def template LoadStoreDeclare {{
       public:
 
         /// Constructor.
-        %(class_name)s(MachInst machInst);
+        %(class_name)s(ExtMachInst machInst);
 
         %(BasicExecDeclare)s
 
@@ -186,19 +186,19 @@ def template LoadStoreConstructor {{
     /** TODO: change op_class to AddrGenOp or something (requires
      * creating new member of OpClass enum in op_class.hh, updating
      * config files, etc.). */
-    inline %(class_name)s::EAComp::EAComp(MachInst machInst)
+    inline %(class_name)s::EAComp::EAComp(ExtMachInst machInst)
         : %(base_class)s("%(mnemonic)s (EAComp)", machInst, IntAluOp)
     {
         %(ea_constructor)s;
     }
 
-    inline %(class_name)s::MemAcc::MemAcc(MachInst machInst)
+    inline %(class_name)s::MemAcc::MemAcc(ExtMachInst machInst)
         : %(base_class)s("%(mnemonic)s (MemAcc)", machInst, %(op_class)s)
     {
         %(memacc_constructor)s;
     }
 
-    inline %(class_name)s::%(class_name)s(MachInst machInst)
+    inline %(class_name)s::%(class_name)s(ExtMachInst machInst)
          : %(base_class)s("%(mnemonic)s", machInst, %(op_class)s,
                           new EAComp(machInst), new MemAcc(machInst))
     {
diff --git a/arch/alpha/isa/opcdec.isa b/arch/alpha/isa/opcdec.isa
new file mode 100644
index 000000000..bb2f91e5c
--- /dev/null
+++ b/arch/alpha/isa/opcdec.isa
@@ -0,0 +1,72 @@
+// -*- mode:c++ -*-
+
+// Copyright (c) 2003-2005 The Regents of The University of Michigan
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met: redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer;
+// redistributions in binary form must reproduce the above copyright
+// notice, this list of conditions and the following disclaimer in the
+// documentation and/or other materials provided with the distribution;
+// neither the name of the copyright holders nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+output header {{
+    /**
+     * Static instruction class for instructions that cause an OPCDEC fault
+     * when executed.  This is currently only for PAL mode instructions
+     * executed in non-PAL mode.
+     */
+    class OpcdecFault : public AlphaStaticInst
+    {
+      public:
+        /// Constructor
+        OpcdecFault(ExtMachInst _machInst)
+            : AlphaStaticInst("opcdec fault", _machInst, No_OpClass)
+        {
+        }
+
+        %(BasicExecDeclare)s
+
+        std::string
+        generateDisassembly(Addr pc, const SymbolTable *symtab) const;
+    };
+}};
+
+output decoder {{
+    std::string
+    OpcdecFault::generateDisassembly(Addr pc, const SymbolTable *symtab) const
+    {
+        return csprintf("%-10s (inst 0x%x, opcode 0x%x)",
+                        " OPCDEC fault", machInst, OPCODE);
+    }
+}};
+
+output exec {{
+    Fault
+    OpcdecFault::execute(%(CPU_exec_context)s *xc,
+                     Trace::InstRecord *traceData) const
+    {
+        return new UnimplementedOpcodeFault;
+    }
+}};
+
+def format OpcdecFault() {{
+    decode_block = 'return new OpcdecFault(machInst);\n'
+}};
+
diff --git a/arch/alpha/isa/pal.isa b/arch/alpha/isa/pal.isa
index 49e5bff12..e07bea5a8 100644
--- a/arch/alpha/isa/pal.isa
+++ b/arch/alpha/isa/pal.isa
@@ -36,7 +36,7 @@ output header {{
       protected:
 
         /// Constructor.
-        EmulatedCallPal(const char *mnem, MachInst _machInst,
+        EmulatedCallPal(const char *mnem, ExtMachInst _machInst,
                         OpClass __opClass)
             : AlphaStaticInst(mnem, _machInst, __opClass)
         {
@@ -83,7 +83,7 @@ output header {{
         bool palPriv;	///< is this call privileged?
 
         /// Constructor.
-        CallPalBase(const char *mnem, MachInst _machInst,
+        CallPalBase(const char *mnem, ExtMachInst _machInst,
                     OpClass __opClass);
 
         std::string
@@ -93,7 +93,7 @@ output header {{
 
 output decoder {{
     inline
-    CallPalBase::CallPalBase(const char *mnem, MachInst _machInst,
+    CallPalBase::CallPalBase(const char *mnem, ExtMachInst _machInst,
                              OpClass __opClass)
         : AlphaStaticInst(mnem, _machInst, __opClass),
         palFunc(PALFUNC)
@@ -148,7 +148,7 @@ output header {{
         int16_t disp;
 
         /// Constructor
-        HwLoadStore(const char *mnem, MachInst _machInst, OpClass __opClass,
+        HwLoadStore(const char *mnem, ExtMachInst _machInst, OpClass __opClass,
                     StaticInstPtr _eaCompPtr = nullStaticInstPtr,
                     StaticInstPtr _memAccPtr = nullStaticInstPtr);
 
@@ -160,7 +160,7 @@ output header {{
 
 output decoder {{
     inline
-    HwLoadStore::HwLoadStore(const char *mnem, MachInst _machInst,
+    HwLoadStore::HwLoadStore(const char *mnem, ExtMachInst _machInst,
                              OpClass __opClass,
                              StaticInstPtr _eaCompPtr,
                              StaticInstPtr _memAccPtr)
@@ -231,7 +231,7 @@ output header {{
         int ipr_index;
 
         /// Constructor
-        HwMoveIPR(const char *mnem, MachInst _machInst, OpClass __opClass)
+        HwMoveIPR(const char *mnem, ExtMachInst _machInst, OpClass __opClass)
             : AlphaStaticInst(mnem, _machInst, __opClass),
               ipr_index(HW_IPR_IDX)
         {
diff --git a/arch/alpha/isa/unimp.isa b/arch/alpha/isa/unimp.isa
index 09df39706..392522801 100644
--- a/arch/alpha/isa/unimp.isa
+++ b/arch/alpha/isa/unimp.isa
@@ -38,7 +38,7 @@ output header {{
     {
       public:
         /// Constructor
-        FailUnimplemented(const char *_mnemonic, MachInst _machInst)
+        FailUnimplemented(const char *_mnemonic, ExtMachInst _machInst)
             : AlphaStaticInst(_mnemonic, _machInst, No_OpClass)
         {
             // don't call execute() (which panics) if we're on a
@@ -69,7 +69,7 @@ output header {{
 
       public:
         /// Constructor
-        WarnUnimplemented(const char *_mnemonic, MachInst _machInst)
+        WarnUnimplemented(const char *_mnemonic, ExtMachInst _machInst)
             : AlphaStaticInst(_mnemonic, _machInst, No_OpClass), warned(false)
         {
             // don't call execute() (which panics) if we're on a
@@ -148,7 +148,7 @@ output header {{
     {
       public:
         /// Constructor
-        Unknown(MachInst _machInst)
+        Unknown(ExtMachInst _machInst)
             : AlphaStaticInst("unknown", _machInst, No_OpClass)
         {
             // don't call execute() (which panics) if we're on a
diff --git a/arch/alpha/isa_traits.hh b/arch/alpha/isa_traits.hh
index 938ba696e..b1980b4b6 100644
--- a/arch/alpha/isa_traits.hh
+++ b/arch/alpha/isa_traits.hh
@@ -57,16 +57,18 @@ namespace AlphaISA
 {
 
     typedef uint32_t MachInst;
+    typedef uint64_t ExtMachInst;
 //    typedef uint64_t Addr;
     typedef uint8_t  RegIndex;
 
     enum {
         MemoryEnd = 0xffffffffffffffffULL,
 
-        NumIntRegs = 32,
-        NumFloatRegs = 32,
+        NumIntArchRegs = 32,
+        NumPALShadowRegs = 8,
+        NumFloatArchRegs = 32,
         // @todo: Figure out what this number really should be.
-        NumMiscRegs = 32,
+        NumMiscArchRegs = 32,
 
         MaxRegsOfAnyType = 32,
         // Static instruction parameters
@@ -100,17 +102,23 @@ namespace AlphaISA
         DepNA = 0,
     };
 
+    enum {
+        NumIntRegs = NumIntArchRegs + NumPALShadowRegs,
+        NumFloatRegs = NumFloatArchRegs,
+        NumMiscRegs = NumMiscArchRegs
+    };
+
     // These enumerate all the registers for dependence tracking.
     enum DependenceTags {
         // 0..31 are the integer regs 0..31
         // 32..63 are the FP regs 0..31, i.e. use (reg + FP_Base_DepTag)
-        FP_Base_DepTag = 32,
-        Ctrl_Base_DepTag = 64,
-        Fpcr_DepTag = 64,		// floating point control register
-        Uniq_DepTag = 65,
-        Lock_Flag_DepTag = 66,
-        Lock_Addr_DepTag = 67,
-        IPR_Base_DepTag = 68
+        FP_Base_DepTag = 40,
+        Ctrl_Base_DepTag = 72,
+        Fpcr_DepTag = 72,		// floating point control register
+        Uniq_DepTag = 73,
+        Lock_Flag_DepTag = 74,
+        Lock_Addr_DepTag = 75,
+        IPR_Base_DepTag = 76
     };
 
     typedef uint64_t IntReg;
@@ -132,6 +140,9 @@ extern const Addr PageBytes;
 extern const Addr PageMask;
 extern const Addr PageOffset;
 
+// redirected register map, really only used for the full system case.
+extern const int reg_redir[NumIntRegs];
+
 #if FULL_SYSTEM
 
     typedef uint64_t InternalProcReg;
@@ -199,9 +210,7 @@ extern const Addr PageOffset;
         Addr pc;			// program counter
         Addr npc;			// next-cycle program counter
 #if FULL_SYSTEM
-        IntReg palregs[NumIntRegs];	// PAL shadow registers
         int intrflag;			// interrupt flag
-        bool pal_shadow;		// using pal_shadow registers
         inline int instAsid()
         { return EV5::ITB_ASN_ASN(miscRegs.ipr[IPR_ITB_ASN]); }
         inline int dataAsid()
@@ -212,10 +221,12 @@ extern const Addr PageOffset;
         void unserialize(Checkpoint *cp, const std::string &section);
     };
 
-    StaticInstPtr decodeInst(MachInst);
+    static inline ExtMachInst makeExtMI(MachInst inst, const uint64_t &pc);
+
+    StaticInstPtr decodeInst(ExtMachInst);
 
     // return a no-op instruction... used for instruction fetch faults
-    extern const MachInst NoopMachInst;
+    extern const ExtMachInst NoopMachInst;
 
     enum annotes {
         ANNOTE_NONE = 0,
@@ -362,6 +373,18 @@ class SyscallReturn {
 
 #endif
 
+static inline AlphaISA::ExtMachInst
+AlphaISA::makeExtMI(AlphaISA::MachInst inst, const uint64_t &pc) {
+#if FULL_SYSTEM
+    AlphaISA::ExtMachInst ext_inst = inst;
+    if (pc && 0x1)
+        return ext_inst|=(static_cast<AlphaISA::ExtMachInst>(pc & 0x1) << 32);
+    else
+        return ext_inst;
+#else
+    return AlphaISA::ExtMachInst(inst);
+#endif
+}
 
 #if FULL_SYSTEM
 //typedef TheISA::InternalProcReg InternalProcReg;
diff --git a/arch/isa_parser.py b/arch/isa_parser.py
index 5185ed573..570110d84 100755
--- a/arch/isa_parser.py
+++ b/arch/isa_parser.py
@@ -225,7 +225,7 @@ def p_specification(t):
     # wrap the decode block as a function definition
     t[4].wrap_decode_block('''
 StaticInstPtr
-%(isa_name)s::decodeInst(%(isa_name)s::MachInst machInst)
+%(isa_name)s::decodeInst(%(isa_name)s::ExtMachInst machInst)
 {
     using namespace %(namespace)s;
 ''' % vars(), '}')
diff --git a/base/remote_gdb.cc b/base/remote_gdb.cc
index f56ddf7cf..57a179719 100644
--- a/base/remote_gdb.cc
+++ b/base/remote_gdb.cc
@@ -424,12 +424,25 @@ void
 RemoteGDB::getregs()
 {
     memset(gdbregs, 0, sizeof(gdbregs));
-    memcpy(&gdbregs[KGDB_REG_V0], context->regs.intRegFile, 32 * sizeof(uint64_t));
+
+    gdbregs[KGDB_REG_PC] = context->readPC();
+
+    // @todo: Currently this is very Alpha specific.
+    if (AlphaISA::PcPAL(gdbregs[KGDB_REG_PC])) {
+        for (int i = 0; i < TheISA::NumIntArchRegs; ++i) {
+            gdbregs[i] = context->readIntReg(AlphaISA::reg_redir[i]);
+        }
+    } else {
+        for (int i = 0; i < TheISA::NumIntArchRegs; ++i) {
+            gdbregs[i] = context->readIntReg(i);
+        }
+    }
+
 #ifdef KGDB_FP_REGS
-    memcpy(&gdbregs[KGDB_REG_F0], context->regs.floatRegFile.q,
-           32 * sizeof(uint64_t));
+    for (int i = 0; i < TheISA::NumFloatArchRegs; ++i) {
+        gdbregs[i + KGDB_REG_F0] = context->readFloatRegInt(i);
+    }
 #endif
-    gdbregs[KGDB_REG_PC] = context->regs.pc;
 }
 
 ///////////////////////////////////////////////////////////
@@ -441,11 +454,21 @@ RemoteGDB::getregs()
 void
 RemoteGDB::setregs()
 {
-    memcpy(context->regs.intRegFile, &gdbregs[KGDB_REG_V0],
-           32 * sizeof(uint64_t));
+    // @todo: Currently this is very Alpha specific.
+    if (AlphaISA::PcPAL(gdbregs[KGDB_REG_PC])) {
+        for (int i = 0; i < TheISA::NumIntArchRegs; ++i) {
+            context->setIntReg(AlphaISA::reg_redir[i], gdbregs[i]);
+        }
+    } else {
+        for (int i = 0; i < TheISA::NumIntArchRegs; ++i) {
+            context->setIntReg(i, gdbregs[i]);
+        }
+    }
+
 #ifdef KGDB_FP_REGS
-    memcpy(context->regs.floatRegFile.q, &gdbregs[KGDB_REG_F0],
-           32 * sizeof(uint64_t));
+    for (int i = 0; i < TheISA::NumFloatArchRegs; ++i) {
+        context->setFloatRegInt(i, gdbregs[i + KGDB_REG_F0]);
+    }
 #endif
     context->regs.pc = gdbregs[KGDB_REG_PC];
 }
diff --git a/cpu/o3/regfile.hh b/cpu/o3/regfile.hh
index 691a75382..03ad2da46 100644
--- a/cpu/o3/regfile.hh
+++ b/cpu/o3/regfile.hh
@@ -236,7 +236,7 @@ class PhysRegFile
 #if FULL_SYSTEM
   private:
     // This is ISA specifc stuff; remove it eventually once ISAImpl is used
-    IntReg palregs[NumIntRegs];	// PAL shadow registers
+//    IntReg palregs[NumIntRegs];	// PAL shadow registers
     InternalProcReg ipr[NumInternalProcRegs]; // internal processor regs
     int intrflag;			// interrupt flag
     bool pal_shadow;		// using pal_shadow registers
diff --git a/cpu/simple/cpu.cc b/cpu/simple/cpu.cc
index d826c589e..2006f4fe8 100644
--- a/cpu/simple/cpu.cc
+++ b/cpu/simple/cpu.cc
@@ -761,7 +761,7 @@ SimpleCPU::tick()
 
         // decode the instruction
         inst = gtoh(inst);
-        curStaticInst = StaticInst::decode(inst);
+        curStaticInst = StaticInst::decode(makeExtMI(inst, xc->readPC()));
 
         traceData = Trace::getInstRecord(curTick, xc, this, curStaticInst,
                                          xc->regs.pc);
diff --git a/cpu/static_inst.hh b/cpu/static_inst.hh
index 5566f2f6d..20116554e 100644
--- a/cpu/static_inst.hh
+++ b/cpu/static_inst.hh
@@ -231,6 +231,8 @@ class StaticInst : public StaticInstBase
 
     /// Binary machine instruction type.
     typedef TheISA::MachInst MachInst;
+    /// Binary extended machine instruction type.
+    typedef TheISA::ExtMachInst ExtMachInst;
     /// Logical register index type.
     typedef TheISA::RegIndex RegIndex;
 
@@ -272,7 +274,7 @@ class StaticInst : public StaticInstBase
     StaticInstPtr &memAccInst() const { return nullStaticInstPtr; }
 
     /// The binary machine instruction.
-    const MachInst machInst;
+    const ExtMachInst machInst;
 
   protected:
 
@@ -302,7 +304,7 @@ class StaticInst : public StaticInstBase
     generateDisassembly(Addr pc, const SymbolTable *symtab) const = 0;
 
     /// Constructor.
-    StaticInst(const char *_mnemonic, MachInst _machInst, OpClass __opClass)
+    StaticInst(const char *_mnemonic, ExtMachInst _machInst, OpClass __opClass)
         : StaticInstBase(__opClass),
           machInst(_machInst), mnemonic(_mnemonic), cachedDisassembly(0)
     {
@@ -372,7 +374,7 @@ class StaticInst : public StaticInstBase
     /// Decoded instruction cache type.
     /// For now we're using a generic hash_map; this seems to work
     /// pretty well.
-    typedef m5::hash_map<MachInst, StaticInstPtr> DecodeCache;
+    typedef m5::hash_map<ExtMachInst, StaticInstPtr> DecodeCache;
 
     /// A cache of decoded instruction objects.
     static DecodeCache decodeCache;
@@ -387,7 +389,7 @@ class StaticInst : public StaticInstBase
     /// @param mach_inst The binary instruction to decode.
     /// @retval A pointer to the corresponding StaticInst object.
     //This is defined as inline below.
-    static StaticInstPtr decode(MachInst mach_inst);
+    static StaticInstPtr decode(ExtMachInst mach_inst);
 };
 
 typedef RefCountingPtr<StaticInstBase> StaticInstBasePtr;
@@ -418,7 +420,7 @@ class StaticInstPtr : public RefCountingPtr<StaticInst>
 
     /// Construct directly from machine instruction.
     /// Calls StaticInst::decode().
-    StaticInstPtr(TheISA::MachInst mach_inst)
+    StaticInstPtr(TheISA::ExtMachInst mach_inst)
         : RefCountingPtr<StaticInst>(StaticInst::decode(mach_inst))
     {
     }
@@ -431,7 +433,7 @@ class StaticInstPtr : public RefCountingPtr<StaticInst>
 };
 
 inline StaticInstPtr
-StaticInst::decode(StaticInst::MachInst mach_inst)
+StaticInst::decode(StaticInst::ExtMachInst mach_inst)
 {
 #ifdef DECODE_CACHE_HASH_STATS
     // Simple stats on decode hash_map.  Turns out the default