From 10c2e37f604280fb89d800839cc965204d096c59 Mon Sep 17 00:00:00 2001
From: Gabe Black <gblack@eecs.umich.edu>
Date: Mon, 19 Sep 2011 02:46:48 -0700
Subject: [PATCH] Syscall: Make the syscall function available in both SE and
 FS modes.

In FS mode the syscall function will panic, but the interface will be
consistent and code which calls syscall can be compiled in. This will allow,
for instance, instructions that use syscall to be built unconditionally but
then not returned by the decoder.
---
 src/cpu/inorder/inorder_dyn_inst.cc |  8 ++++++--
 src/cpu/inorder/inorder_dyn_inst.hh |  4 ++--
 src/cpu/o3/dyn_inst.hh              |  6 +++---
 src/cpu/o3/dyn_inst_impl.hh         |  8 ++++++--
 src/cpu/simple/base.hh              | 10 +++++++++-
 5 files changed, 26 insertions(+), 10 deletions(-)

diff --git a/src/cpu/inorder/inorder_dyn_inst.cc b/src/cpu/inorder/inorder_dyn_inst.cc
index f65d2ea9f..ff178f6d3 100644
--- a/src/cpu/inorder/inorder_dyn_inst.cc
+++ b/src/cpu/inorder/inorder_dyn_inst.cc
@@ -311,14 +311,18 @@ InOrderDynInst::simPalCheck(int palFunc)
 #endif
     return this->cpu->simPalCheck(palFunc, this->threadNumber);
 }
-#else
+#endif
+
 void
 InOrderDynInst::syscall(int64_t callnum)
 {
+#if FULL_SYSTEM
+    panic("Syscall emulation isn't available in FS mode.\n");
+#else
     syscallNum = callnum;
     cpu->syscallContext(NoFault, this->threadNumber, this);
-}
 #endif
+}
 
 void
 InOrderDynInst::setSquashInfo(unsigned stage_num)
diff --git a/src/cpu/inorder/inorder_dyn_inst.hh b/src/cpu/inorder/inorder_dyn_inst.hh
index 3427af86b..f49476ec5 100644
--- a/src/cpu/inorder/inorder_dyn_inst.hh
+++ b/src/cpu/inorder/inorder_dyn_inst.hh
@@ -525,10 +525,10 @@ class InOrderDynInst : public FastAlloc, public RefCounted
     bool simPalCheck(int palFunc);
 #else
     short syscallNum;
+#endif
 
-    /** Calls a syscall. */
+    /** Emulates a syscall. */
     void syscall(int64_t callnum);
-#endif
 
     ////////////////////////////////////////////////////////////
     //
diff --git a/src/cpu/o3/dyn_inst.hh b/src/cpu/o3/dyn_inst.hh
index 399240d69..e58eb99c5 100644
--- a/src/cpu/o3/dyn_inst.hh
+++ b/src/cpu/o3/dyn_inst.hh
@@ -205,11 +205,11 @@ class BaseO3DynInst : public BaseDynInst<Impl>
     /** Traps to handle specified fault. */
     void trap(Fault fault);
     bool simPalCheck(int palFunc);
-#else
-    /** Calls a syscall. */
-    void syscall(int64_t callnum);
 #endif
 
+    /** Emulates a syscall. */
+    void syscall(int64_t callnum);
+
   public:
 
     // The register accessor methods provide the index of the
diff --git a/src/cpu/o3/dyn_inst_impl.hh b/src/cpu/o3/dyn_inst_impl.hh
index eceb0b49f..500d63de8 100644
--- a/src/cpu/o3/dyn_inst_impl.hh
+++ b/src/cpu/o3/dyn_inst_impl.hh
@@ -188,11 +188,15 @@ BaseO3DynInst<Impl>::simPalCheck(int palFunc)
 #endif
     return this->cpu->simPalCheck(palFunc, this->threadNumber);
 }
-#else
+#endif
+
 template <class Impl>
 void
 BaseO3DynInst<Impl>::syscall(int64_t callnum)
 {
+#if FULL_SYSTEM
+    panic("Syscall emulation isn't available in FS mode.\n");
+#else
     // HACK: check CPU's nextPC before and after syscall. If it
     // changes, update this instruction's nextPC because the syscall
     // must have changed the nextPC.
@@ -202,6 +206,6 @@ BaseO3DynInst<Impl>::syscall(int64_t callnum)
     if (!(curPC == newPC)) {
         this->pcState(newPC);
     }
-}
 #endif
+}
 
diff --git a/src/cpu/simple/base.hh b/src/cpu/simple/base.hh
index b27ebf998..ad281aa2b 100644
--- a/src/cpu/simple/base.hh
+++ b/src/cpu/simple/base.hh
@@ -402,9 +402,17 @@ class BaseSimpleCPU : public BaseCPU
 #if FULL_SYSTEM
     Fault hwrei() { return thread->hwrei(); }
     bool simPalCheck(int palFunc) { return thread->simPalCheck(palFunc); }
+#endif
+
+    void
+    syscall(int64_t callnum)
+    {
+#if FULL_SYSTEM
+        panic("Syscall emulation isn't available in FS mode.\n");
 #else
-    void syscall(int64_t callnum) { thread->syscall(callnum); }
+        thread->syscall(callnum);
 #endif
+    }
 
     bool misspeculating() { return thread->misspeculating(); }
     ThreadContext *tcBase() { return tc; }
-- 
2.30.2