Split Alpha ISA description into multiple files

(thanks to Gabe's include feature!).

arch/alpha/isa/main.isa:
    Split out into multiple .isa files.

--HG--
extra : convert_revision : 30d8edf74ea194d4a208febf1e66edc72a7dbd5d

1 files changed, 259 insertions, 0 deletions

diff --git a/arch/alpha/isa/branch.isa b/arch/alpha/isa/branch.isa
new file mode 100644
index 000000000..e9c790c53
--- /dev/null
+++ b/arch/alpha/isa/branch.isa
@@ -0,0 +1,259 @@
+// -*- 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 {{
+
+    /**
+     * Base class for instructions whose disassembly is not purely a
+     * function of the machine instruction (i.e., it depends on the
+     * PC).  This class overrides the disassemble() method to check
+     * the PC and symbol table values before re-using a cached
+     * disassembly string.  This is necessary for branches and jumps,
+     * where the disassembly string includes the target address (which
+     * may depend on the PC and/or symbol table).
+     */
+    class PCDependentDisassembly : public AlphaStaticInst
+    {
+      protected:
+        /// Cached program counter from last disassembly
+        mutable Addr cachedPC;
+        /// Cached symbol table pointer from last disassembly
+        mutable const SymbolTable *cachedSymtab;
+
+        /// Constructor
+        PCDependentDisassembly(const char *mnem, MachInst _machInst,
+                               OpClass __opClass)
+            : AlphaStaticInst(mnem, _machInst, __opClass),
+              cachedPC(0), cachedSymtab(0)
+        {
+        }
+
+        const std::string &
+        disassemble(Addr pc, const SymbolTable *symtab) const;
+    };
+
+    /**
+     * Base class for branches (PC-relative control transfers),
+     * conditional or unconditional.
+     */
+    class Branch : public PCDependentDisassembly
+    {
+      protected:
+        /// Displacement to target address (signed).
+        int32_t disp;
+
+        /// Constructor.
+        Branch(const char *mnem, MachInst _machInst, OpClass __opClass)
+            : PCDependentDisassembly(mnem, _machInst, __opClass),
+              disp(BRDISP << 2)
+        {
+        }
+
+        Addr branchTarget(Addr branchPC) const;
+
+        std::string
+        generateDisassembly(Addr pc, const SymbolTable *symtab) const;
+    };
+
+    /**
+     * Base class for jumps (register-indirect control transfers).  In
+     * the Alpha ISA, these are always unconditional.
+     */
+    class Jump : public PCDependentDisassembly
+    {
+      protected:
+
+        /// Displacement to target address (signed).
+        int32_t disp;
+
+      public:
+        /// Constructor
+        Jump(const char *mnem, MachInst _machInst, OpClass __opClass)
+            : PCDependentDisassembly(mnem, _machInst, __opClass),
+              disp(BRDISP)
+        {
+        }
+
+        Addr branchTarget(ExecContext *xc) const;
+
+        std::string
+        generateDisassembly(Addr pc, const SymbolTable *symtab) const;
+    };
+}};
+
+output decoder {{
+    Addr
+    Branch::branchTarget(Addr branchPC) const
+    {
+        return branchPC + 4 + disp;
+    }
+
+    Addr
+    Jump::branchTarget(ExecContext *xc) const
+    {
+        Addr NPC = xc->readPC() + 4;
+        uint64_t Rb = xc->readIntReg(_srcRegIdx[0]);
+        return (Rb & ~3) | (NPC & 1);
+    }
+
+    const std::string &
+    PCDependentDisassembly::disassemble(Addr pc,
+                                        const SymbolTable *symtab) const
+    {
+        if (!cachedDisassembly ||
+            pc != cachedPC || symtab != cachedSymtab)
+        {
+            if (cachedDisassembly)
+                delete cachedDisassembly;
+
+            cachedDisassembly =
+                new std::string(generateDisassembly(pc, symtab));
+            cachedPC = pc;
+            cachedSymtab = symtab;
+        }
+
+        return *cachedDisassembly;
+    }
+
+    std::string
+    Branch::generateDisassembly(Addr pc, const SymbolTable *symtab) const
+    {
+        std::stringstream ss;
+
+        ccprintf(ss, "%-10s ", mnemonic);
+
+        // There's only one register arg (RA), but it could be
+        // either a source (the condition for conditional
+        // branches) or a destination (the link reg for
+        // unconditional branches)
+        if (_numSrcRegs > 0) {
+            printReg(ss, _srcRegIdx[0]);
+            ss << ",";
+        }
+        else if (_numDestRegs > 0) {
+            printReg(ss, _destRegIdx[0]);
+            ss << ",";
+        }
+
+#ifdef SS_COMPATIBLE_DISASSEMBLY
+        if (_numSrcRegs == 0 && _numDestRegs == 0) {
+            printReg(ss, 31);
+            ss << ",";
+        }
+#endif
+
+        Addr target = pc + 4 + disp;
+
+        std::string str;
+        if (symtab && symtab->findSymbol(target, str))
+            ss << str;
+        else
+            ccprintf(ss, "0x%x", target);
+
+        return ss.str();
+    }
+
+    std::string
+    Jump::generateDisassembly(Addr pc, const SymbolTable *symtab) const
+    {
+        std::stringstream ss;
+
+        ccprintf(ss, "%-10s ", mnemonic);
+
+#ifdef SS_COMPATIBLE_DISASSEMBLY
+        if (_numDestRegs == 0) {
+            printReg(ss, 31);
+            ss << ",";
+        }
+#endif
+
+        if (_numDestRegs > 0) {
+            printReg(ss, _destRegIdx[0]);
+            ss << ",";
+        }
+
+        ccprintf(ss, "(r%d)", RB);
+
+        return ss.str();
+    }
+}};
+
+def template JumpOrBranchDecode {{
+    return (RA == 31)
+        ? (StaticInst<AlphaISA> *)new %(class_name)s(machInst)
+        : (StaticInst<AlphaISA> *)new %(class_name)sAndLink(machInst);
+}};
+
+def format CondBranch(code) {{
+    code = 'bool cond;\n' + code + '\nif (cond) NPC = NPC + disp;\n';
+    iop = InstObjParams(name, Name, 'Branch', CodeBlock(code),
+                        ('IsDirectControl', 'IsCondControl'))
+    header_output = BasicDeclare.subst(iop)
+    decoder_output = BasicConstructor.subst(iop)
+    decode_block = BasicDecode.subst(iop)
+    exec_output = BasicExecute.subst(iop)
+}};
+
+let {{
+def UncondCtrlBase(name, Name, base_class, npc_expr, flags):
+    # Declare basic control transfer w/o link (i.e. link reg is R31)
+    nolink_code = 'NPC = %s;\n' % npc_expr
+    nolink_iop = InstObjParams(name, Name, base_class,
+                               CodeBlock(nolink_code), flags)
+    header_output = BasicDeclare.subst(nolink_iop)
+    decoder_output = BasicConstructor.subst(nolink_iop)
+    exec_output = BasicExecute.subst(nolink_iop)
+
+    # Generate declaration of '*AndLink' version, append to decls
+    link_code = 'Ra = NPC & ~3;\n' + nolink_code
+    link_iop = InstObjParams(name, Name + 'AndLink', base_class,
+                             CodeBlock(link_code), flags)
+    header_output += BasicDeclare.subst(link_iop)
+    decoder_output += BasicConstructor.subst(link_iop)
+    exec_output += BasicExecute.subst(link_iop)
+
+    # need to use link_iop for the decode template since it is expecting
+    # the shorter version of class_name (w/o "AndLink")
+
+    return (header_output, decoder_output,
+            JumpOrBranchDecode.subst(nolink_iop), exec_output)
+}};
+
+def format UncondBranch(*flags) {{
+    flags += ('IsUncondControl', 'IsDirectControl')
+    (header_output, decoder_output, decode_block, exec_output) = \
+        UncondCtrlBase(name, Name, 'Branch', 'NPC + disp', flags)
+}};
+
+def format Jump(*flags) {{
+    flags += ('IsUncondControl', 'IsIndirectControl')
+    (header_output, decoder_output, decode_block, exec_output) = \
+        UncondCtrlBase(name, Name, 'Jump', '(Rb & ~3) | (NPC & 1)', flags)
+}};
+
+