O3CPU: Undo Gabe's changes to remove hwrei and simpalcheck from O3 CPU. Removing hwrei causes

the instruction after the hwrei to be fetched before the ITB/DTB_CM register is updated in a call pal
call sys and thus the translation fails because the user is attempting to access a super page address.

Minimally, it seems as though some sort of fetch stall or refetch after a hwrei is required. I think
this works currently because the hwrei uses the exec context interface, and the o3 stalls when that occurs.

Additionally, these changes don't update the LOCK register and probably break ll/sc. Both o3 changes were
removed since a great deal of manual patching would be required to only remove the hwrei change.

3 files changed, 52 insertions, 35 deletions

diff --git a/src/arch/alpha/ev5.cc b/src/arch/alpha/ev5.cc
index c11b3632e..7dc02a611 100644
--- a/src/arch/alpha/ev5.cc
+++ b/src/arch/alpha/ev5.cc
@@ -547,3 +547,53 @@ copyIprs(ThreadContext *src, ThreadContext *dest)
 }
 
 } // namespace AlphaISA
+
+#if FULL_SYSTEM
+
+using namespace AlphaISA;
+
+Fault
+SimpleThread::hwrei()
+{
+    if (!(readPC() & 0x3))
+        return new UnimplementedOpcodeFault;
+
+    setNextPC(readMiscRegNoEffect(IPR_EXC_ADDR));
+
+    if (!misspeculating()) {
+        if (kernelStats)
+            kernelStats->hwrei();
+    }
+
+    // FIXME: XXX check for interrupts? XXX
+    return NoFault;
+}
+
+/**
+ * Check for special simulator handling of specific PAL calls.
+ * If return value is false, actual PAL call will be suppressed.
+ */
+bool
+SimpleThread::simPalCheck(int palFunc)
+{
+    if (kernelStats)
+        kernelStats->callpal(palFunc, tc);
+
+    switch (palFunc) {
+      case PAL::halt:
+        halt();
+        if (--System::numSystemsRunning == 0)
+            exitSimLoop("all cpus halted");
+        break;
+
+      case PAL::bpt:
+      case PAL::bugchk:
+        if (system->breakpoint())
+            return false;
+        break;
+    }
+
+    return true;
+}
+
+#endif // FULL_SYSTEM
diff --git a/src/arch/alpha/isa/decoder.isa b/src/arch/alpha/isa/decoder.isa
index 06676ae87..270940df2 100644
--- a/src/arch/alpha/isa/decoder.isa
+++ b/src/arch/alpha/isa/decoder.isa
@@ -698,28 +698,7 @@ decode OPCODE default Unknown::unknown() {
         else {
             // check to see if simulator wants to do something special
             // on this PAL call (including maybe suppress it)
-            
-            bool dopal = true;
-
-            ThreadContext * tc = xc->tcBase();
-            AlphaISA::Kernel::Statistics * kernelStats = tc->getKernelStats();
-            System * system = tc->getSystemPtr();
-            if (kernelStats)
-                kernelStats->callpal(palFunc, tc);
-
-            switch (palFunc) {
-              case PAL::halt:
-                tc->halt();
-                if (--System::numSystemsRunning == 0)
-                    exitSimLoop("all cpus halted");
-                break;
-
-              case PAL::bpt:
-              case PAL::bugchk:
-                if (system->breakpoint())
-                    dopal = false;
-                break;
-            }
+            bool dopal = xc->simPalCheck(palFunc);
 
             if (dopal) {
                 xc->setMiscReg(IPR_EXC_ADDR, NPC);
@@ -807,16 +786,7 @@ decode OPCODE default Unknown::unknown() {
     format BasicOperate {
         0x1e: decode PALMODE {
             0: OpcdecFault::hw_rei();
-            1: hw_rei({{
-                NPC = ExcAddr;
-                ThreadContext * tc = xc->tcBase();
-                if (!tc->misspeculating()) {
-                    AlphaISA::Kernel::Statistics * kernelStats =
-                        tc->getKernelStats();
-                    if (kernelStats)
-                        kernelStats->hwrei();
-                }
-            }}, IsSerializing, IsSerializeBefore);
+            1:hw_rei({{ xc->hwrei(); }}, IsSerializing, IsSerializeBefore);
         }
 
         // M5 special opcodes use the reserved 0x01 opcode space
diff --git a/src/arch/alpha/isa/main.isa b/src/arch/alpha/isa/main.isa
index 0f7f74359..5231712c8 100644
--- a/src/arch/alpha/isa/main.isa
+++ b/src/arch/alpha/isa/main.isa
@@ -69,8 +69,6 @@ output exec {{
 #include <math.h>
 
 #if FULL_SYSTEM
-#include "arch/alpha/kernel_stats.hh"
-#include "arch/alpha/osfpal.hh"
 #include "sim/pseudo_inst.hh"
 #endif
 #include "arch/alpha/ipr.hh"
@@ -189,7 +187,6 @@ def operands {{
     'Runiq': ('ControlReg', 'uq', 'MISCREG_UNIQ', None, 1),
     'FPCR':  ('ControlReg', 'uq', 'MISCREG_FPCR', None, 1),
     'IntrFlag': ('ControlReg', 'uq', 'MISCREG_INTR', None, 1),
-    'ExcAddr': ('ControlReg', 'uq', 'IPR_EXC_ADDR', None, 1),
     # The next two are hacks for non-full-system call-pal emulation
     'R0':  ('IntReg', 'uq', '0', None, 1),
     'R16': ('IntReg', 'uq', '16', None, 1),