Support for returning unimplemented instruction in the decoder, lifted from Alpha

--HG--
extra : convert_revision : 7e26053696b23fbc0b8cd5827a5072dcf2526e2b

1 files changed, 147 insertions, 0 deletions

diff --git a/src/arch/sparc/isa/formats/unimp.isa b/src/arch/sparc/isa/formats/unimp.isa
new file mode 100644
index 000000000..a623507a1
--- /dev/null
+++ b/src/arch/sparc/isa/formats/unimp.isa
@@ -0,0 +1,147 @@
+// -*- 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.
+//
+// Authors: Steve Reinhardt
+
+////////////////////////////////////////////////////////////////////
+//
+// Unimplemented instructions
+//
+
+output header {{
+    /**
+     * Static instruction class for unimplemented instructions that
+     * cause simulator termination.  Note that these are recognized
+     * (legal) instructions that the simulator does not support; the
+     * 'Unknown' class is used for unrecognized/illegal instructions.
+     * This is a leaf class.
+     */
+    class FailUnimplemented : public SparcStaticInst
+    {
+      public:
+        /// Constructor
+        FailUnimplemented(const char *_mnemonic, ExtMachInst _machInst)
+            : SparcStaticInst(_mnemonic, _machInst, No_OpClass)
+        {
+            // don't call execute() (which panics) if we're on a
+            // speculative path
+            flags[IsNonSpeculative] = true;
+        }
+
+        %(BasicExecDeclare)s
+
+        std::string
+        generateDisassembly(Addr pc, const SymbolTable *symtab) const;
+    };
+
+    /**
+     * Base class for unimplemented instructions that cause a warning
+     * to be printed (but do not terminate simulation).  This
+     * implementation is a little screwy in that it will print a
+     * warning for each instance of a particular unimplemented machine
+     * instruction, not just for each unimplemented opcode.  Should
+     * probably make the 'warned' flag a static member of the derived
+     * class.
+     */
+    class WarnUnimplemented : public SparcStaticInst
+    {
+      private:
+        /// Have we warned on this instruction yet?
+        mutable bool warned;
+
+      public:
+        /// Constructor
+        WarnUnimplemented(const char *_mnemonic, ExtMachInst _machInst)
+            : SparcStaticInst(_mnemonic, _machInst, No_OpClass), warned(false)
+        {
+            // don't call execute() (which panics) if we're on a
+            // speculative path
+            flags[IsNonSpeculative] = true;
+        }
+
+        %(BasicExecDeclare)s
+
+        std::string
+        generateDisassembly(Addr pc, const SymbolTable *symtab) const;
+    };
+}};
+
+output decoder {{
+    std::string
+    FailUnimplemented::generateDisassembly(Addr pc,
+                                           const SymbolTable *symtab) const
+    {
+        return csprintf("%-10s (unimplemented)", mnemonic);
+    }
+
+    std::string
+    WarnUnimplemented::generateDisassembly(Addr pc,
+                                           const SymbolTable *symtab) const
+    {
+#ifdef SS_COMPATIBLE_DISASSEMBLY
+        return csprintf("%-10s", mnemonic);
+#else
+        return csprintf("%-10s (unimplemented)", mnemonic);
+#endif
+    }
+}};
+
+output exec {{
+    Fault
+    FailUnimplemented::execute(%(CPU_exec_context)s *xc,
+                               Trace::InstRecord *traceData) const
+    {
+        panic("attempt to execute unimplemented instruction '%s' "
+              "(inst 0x%08x)", mnemonic, machInst);
+        return NoFault;
+    }
+
+    Fault
+    WarnUnimplemented::execute(%(CPU_exec_context)s *xc,
+                               Trace::InstRecord *traceData) const
+    {
+        if (!warned) {
+            warn("instruction '%s' unimplemented\n", mnemonic);
+            warned = true;
+        }
+
+        return NoFault;
+    }
+}};
+
+
+def format FailUnimpl() {{
+    iop = InstObjParams(name, 'FailUnimplemented')
+    decode_block = BasicDecodeWithMnemonic.subst(iop)
+}};
+
+def format WarnUnimpl() {{
+    iop = InstObjParams(name, 'WarnUnimplemented')
+    decode_block = BasicDecodeWithMnemonic.subst(iop)
+}};
+