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+// -*- 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 general Alpha memory-format instructions.
+ */
+ class Memory : public AlphaStaticInst
+ {
+ protected:
+
+ /// Memory request flags. See mem_req_base.hh.
+ unsigned memAccessFlags;
+ /// Pointer to EAComp object.
+ const StaticInstPtr eaCompPtr;
+ /// Pointer to MemAcc object.
+ const StaticInstPtr memAccPtr;
+
+ /// Constructor
+ Memory(const char *mnem, ExtMachInst _machInst, OpClass __opClass,
+ StaticInstPtr _eaCompPtr = nullStaticInstPtr,
+ StaticInstPtr _memAccPtr = nullStaticInstPtr)
+ : AlphaStaticInst(mnem, _machInst, __opClass),
+ memAccessFlags(0), eaCompPtr(_eaCompPtr), memAccPtr(_memAccPtr)
+ {
+ }
+
+ std::string
+ generateDisassembly(Addr pc, const SymbolTable *symtab) const;
+
+ public:
+
+ const StaticInstPtr &eaCompInst() const { return eaCompPtr; }
+ const StaticInstPtr &memAccInst() const { return memAccPtr; }
+ };
+
+ /**
+ * Base class for memory-format instructions using a 32-bit
+ * displacement (i.e. most of them).
+ */
+ class MemoryDisp32 : public Memory
+ {
+ protected:
+ /// Displacement for EA calculation (signed).
+ int32_t disp;
+
+ /// Constructor.
+ MemoryDisp32(const char *mnem, ExtMachInst _machInst, OpClass __opClass,
+ StaticInstPtr _eaCompPtr = nullStaticInstPtr,
+ StaticInstPtr _memAccPtr = nullStaticInstPtr)
+ : Memory(mnem, _machInst, __opClass, _eaCompPtr, _memAccPtr),
+ disp(MEMDISP)
+ {
+ }
+ };
+
+
+ /**
+ * Base class for a few miscellaneous memory-format insts
+ * that don't interpret the disp field: wh64, fetch, fetch_m, ecb.
+ * None of these instructions has a destination register either.
+ */
+ class MemoryNoDisp : public Memory
+ {
+ protected:
+ /// Constructor
+ MemoryNoDisp(const char *mnem, ExtMachInst _machInst, OpClass __opClass,
+ StaticInstPtr _eaCompPtr = nullStaticInstPtr,
+ StaticInstPtr _memAccPtr = nullStaticInstPtr)
+ : Memory(mnem, _machInst, __opClass, _eaCompPtr, _memAccPtr)
+ {
+ }
+
+ std::string
+ generateDisassembly(Addr pc, const SymbolTable *symtab) const;
+ };
+}};
+
+
+output decoder {{
+ std::string
+ Memory::generateDisassembly(Addr pc, const SymbolTable *symtab) const
+ {
+ return csprintf("%-10s %c%d,%d(r%d)", mnemonic,
+ flags[IsFloating] ? 'f' : 'r', RA, MEMDISP, RB);
+ }
+
+ std::string
+ MemoryNoDisp::generateDisassembly(Addr pc, const SymbolTable *symtab) const
+ {
+ return csprintf("%-10s (r%d)", mnemonic, RB);
+ }
+}};
+
+def format LoadAddress(code) {{
+ iop = InstObjParams(name, Name, 'MemoryDisp32', CodeBlock(code))
+ header_output = BasicDeclare.subst(iop)
+ decoder_output = BasicConstructor.subst(iop)
+ decode_block = BasicDecode.subst(iop)
+ exec_output = BasicExecute.subst(iop)
+}};
+
+
+def template LoadStoreDeclare {{
+ /**
+ * Static instruction class for "%(mnemonic)s".
+ */
+ class %(class_name)s : public %(base_class)s
+ {
+ protected:
+
+ /**
+ * "Fake" effective address computation class for "%(mnemonic)s".
+ */
+ class EAComp : public %(base_class)s
+ {
+ public:
+ /// Constructor
+ EAComp(ExtMachInst machInst);
+
+ %(BasicExecDeclare)s
+ };
+
+ /**
+ * "Fake" memory access instruction class for "%(mnemonic)s".
+ */
+ class MemAcc : public %(base_class)s
+ {
+ public:
+ /// Constructor
+ MemAcc(ExtMachInst machInst);
+
+ %(BasicExecDeclare)s
+ };
+
+ public:
+
+ /// Constructor.
+ %(class_name)s(ExtMachInst machInst);
+
+ %(BasicExecDeclare)s
+
+ %(InitiateAccDeclare)s
+
+ %(CompleteAccDeclare)s
+ };
+}};
+
+
+def template InitiateAccDeclare {{
+ Fault initiateAcc(%(CPU_exec_context)s *, Trace::InstRecord *) const;
+}};
+
+
+def template CompleteAccDeclare {{
+ Fault completeAcc(Packet *, %(CPU_exec_context)s *,
+ Trace::InstRecord *) const;
+}};
+
+
+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(ExtMachInst machInst)
+ : %(base_class)s("%(mnemonic)s (EAComp)", machInst, IntAluOp)
+ {
+ %(ea_constructor)s;
+ }
+
+ 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(ExtMachInst machInst)
+ : %(base_class)s("%(mnemonic)s", machInst, %(op_class)s,
+ new EAComp(machInst), new MemAcc(machInst))
+ {
+ %(constructor)s;
+ }
+}};
+
+
+def template EACompExecute {{
+ Fault
+ %(class_name)s::EAComp::execute(%(CPU_exec_context)s *xc,
+ Trace::InstRecord *traceData) const
+ {
+ Addr EA;
+ Fault fault = NoFault;
+
+ %(fp_enable_check)s;
+ %(op_decl)s;
+ %(op_rd)s;
+ %(code)s;
+
+ if (fault == NoFault) {
+ %(op_wb)s;
+ xc->setEA(EA);
+ }
+
+ return fault;
+ }
+}};
+
+def template LoadMemAccExecute {{
+ Fault
+ %(class_name)s::MemAcc::execute(%(CPU_exec_context)s *xc,
+ Trace::InstRecord *traceData) const
+ {
+ Addr EA;
+ Fault fault = NoFault;
+
+ %(fp_enable_check)s;
+ %(op_decl)s;
+ %(op_rd)s;
+ EA = xc->getEA();
+
+ if (fault == NoFault) {
+ fault = xc->read(EA, (uint%(mem_acc_size)d_t&)Mem, memAccessFlags);
+ %(code)s;
+ }
+
+ if (fault == NoFault) {
+ %(op_wb)s;
+ }
+
+ return fault;
+ }
+}};
+
+
+def template LoadExecute {{
+ Fault %(class_name)s::execute(%(CPU_exec_context)s *xc,
+ Trace::InstRecord *traceData) const
+ {
+ Addr EA;
+ Fault fault = NoFault;
+
+ %(fp_enable_check)s;
+ %(op_decl)s;
+ %(op_rd)s;
+ %(ea_code)s;
+
+ if (fault == NoFault) {
+ fault = xc->read(EA, (uint%(mem_acc_size)d_t&)Mem, memAccessFlags);
+ %(memacc_code)s;
+ }
+
+ if (fault == NoFault) {
+ %(op_wb)s;
+ }
+
+ return fault;
+ }
+}};
+
+
+def template LoadInitiateAcc {{
+ Fault %(class_name)s::initiateAcc(%(CPU_exec_context)s *xc,
+ Trace::InstRecord *traceData) const
+ {
+ Addr EA;
+ Fault fault = NoFault;
+
+ %(fp_enable_check)s;
+ %(op_src_decl)s;
+ %(op_rd)s;
+ %(ea_code)s;
+
+ if (fault == NoFault) {
+ fault = xc->read(EA, (uint%(mem_acc_size)d_t &)Mem, memAccessFlags);
+ }
+
+ return fault;
+ }
+}};
+
+
+def template LoadCompleteAcc {{
+ Fault %(class_name)s::completeAcc(Packet *pkt,
+ %(CPU_exec_context)s *xc,
+ Trace::InstRecord *traceData) const
+ {
+ Fault fault = NoFault;
+
+ %(fp_enable_check)s;
+ %(op_decl)s;
+
+ Mem = pkt->get<typeof(Mem)>();
+
+ if (fault == NoFault) {
+ %(memacc_code)s;
+ }
+
+ if (fault == NoFault) {
+ %(op_wb)s;
+ }
+
+ return fault;
+ }
+}};
+
+
+def template StoreMemAccExecute {{
+ Fault
+ %(class_name)s::MemAcc::execute(%(CPU_exec_context)s *xc,
+ Trace::InstRecord *traceData) const
+ {
+ Addr EA;
+ Fault fault = NoFault;
+ uint64_t write_result = 0;
+
+ %(fp_enable_check)s;
+ %(op_decl)s;
+ %(op_rd)s;
+ EA = xc->getEA();
+
+ if (fault == NoFault) {
+ %(code)s;
+ }
+
+ if (fault == NoFault) {
+ fault = xc->write((uint%(mem_acc_size)d_t&)Mem, EA,
+ memAccessFlags, &write_result);
+ if (traceData) { traceData->setData(Mem); }
+ }
+
+ if (fault == NoFault) {
+ %(postacc_code)s;
+ }
+
+ if (fault == NoFault) {
+ %(op_wb)s;
+ }
+
+ return fault;
+ }
+}};
+
+
+def template StoreExecute {{
+ Fault %(class_name)s::execute(%(CPU_exec_context)s *xc,
+ Trace::InstRecord *traceData) const
+ {
+ Addr EA;
+ Fault fault = NoFault;
+ uint64_t write_result = 0;
+
+ %(fp_enable_check)s;
+ %(op_decl)s;
+ %(op_rd)s;
+ %(ea_code)s;
+
+ if (fault == NoFault) {
+ %(memacc_code)s;
+ }
+
+ if (fault == NoFault) {
+ fault = xc->write((uint%(mem_acc_size)d_t&)Mem, EA,
+ memAccessFlags, &write_result);
+ if (traceData) { traceData->setData(Mem); }
+ }
+
+ if (fault == NoFault) {
+ %(postacc_code)s;
+ }
+
+ if (fault == NoFault) {
+ %(op_wb)s;
+ }
+
+ return fault;
+ }
+}};
+
+def template StoreInitiateAcc {{
+ Fault %(class_name)s::initiateAcc(%(CPU_exec_context)s *xc,
+ Trace::InstRecord *traceData) const
+ {
+ Addr EA;
+ Fault fault = NoFault;
+
+ %(fp_enable_check)s;
+ %(op_decl)s;
+ %(op_rd)s;
+ %(ea_code)s;
+
+ if (fault == NoFault) {
+ %(memacc_code)s;
+ }
+
+ if (fault == NoFault) {
+ fault = xc->write((uint%(mem_acc_size)d_t&)Mem, EA,
+ memAccessFlags, NULL);
+ if (traceData) { traceData->setData(Mem); }
+ }
+
+ return fault;
+ }
+}};
+
+
+def template StoreCompleteAcc {{
+ Fault %(class_name)s::completeAcc(Packet *pkt,
+ %(CPU_exec_context)s *xc,
+ Trace::InstRecord *traceData) const
+ {
+ Fault fault = NoFault;
+
+ %(fp_enable_check)s;
+ %(op_dest_decl)s;
+
+ if (fault == NoFault) {
+ %(postacc_code)s;
+ }
+
+ if (fault == NoFault) {
+ %(op_wb)s;
+ }
+
+ return fault;
+ }
+}};
+
+
+def template StoreCondCompleteAcc {{
+ Fault %(class_name)s::completeAcc(Packet *pkt,
+ %(CPU_exec_context)s *xc,
+ Trace::InstRecord *traceData) const
+ {
+ Fault fault = NoFault;
+
+ %(fp_enable_check)s;
+ %(op_dest_decl)s;
+
+ uint64_t write_result = pkt->req->getScResult();
+
+ if (fault == NoFault) {
+ %(postacc_code)s;
+ }
+
+ if (fault == NoFault) {
+ %(op_wb)s;
+ }
+
+ return fault;
+ }
+}};
+
+
+def template MiscMemAccExecute {{
+ Fault %(class_name)s::MemAcc::execute(%(CPU_exec_context)s *xc,
+ Trace::InstRecord *traceData) const
+ {
+ Addr EA;
+ Fault fault = NoFault;
+
+ %(fp_enable_check)s;
+ %(op_decl)s;
+ %(op_rd)s;
+ EA = xc->getEA();
+
+ if (fault == NoFault) {
+ %(code)s;
+ }
+
+ return NoFault;
+ }
+}};
+
+def template MiscExecute {{
+ Fault %(class_name)s::execute(%(CPU_exec_context)s *xc,
+ Trace::InstRecord *traceData) const
+ {
+ Addr EA;
+ Fault fault = NoFault;
+
+ %(fp_enable_check)s;
+ %(op_decl)s;
+ %(op_rd)s;
+ %(ea_code)s;
+
+ if (fault == NoFault) {
+ %(memacc_code)s;
+ }
+
+ return NoFault;
+ }
+}};
+
+def template MiscInitiateAcc {{
+ Fault %(class_name)s::initiateAcc(%(CPU_exec_context)s *xc,
+ Trace::InstRecord *traceData) const
+ {
+ panic("Misc instruction does not support split access method!");
+ return NoFault;
+ }
+}};
+
+
+def template MiscCompleteAcc {{
+ Fault %(class_name)s::completeAcc(Packet *pkt,
+ %(CPU_exec_context)s *xc,
+ Trace::InstRecord *traceData) const
+ {
+ panic("Misc instruction does not support split access method!");
+
+ return NoFault;
+ }
+}};
+
+// load instructions use Ra as dest, so check for
+// Ra == 31 to detect nops
+def template LoadNopCheckDecode {{
+ {
+ AlphaStaticInst *i = new %(class_name)s(machInst);
+ if (RA == 31) {
+ i = makeNop(i);
+ }
+ return i;
+ }
+}};
+
+
+// for some load instructions, Ra == 31 indicates a prefetch (not a nop)
+def template LoadPrefetchCheckDecode {{
+ {
+ if (RA != 31) {
+ return new %(class_name)s(machInst);
+ }
+ else {
+ return new %(class_name)sPrefetch(machInst);
+ }
+ }
+}};
+
+
+let {{
+def LoadStoreBase(name, Name, ea_code, memacc_code, mem_flags, inst_flags,
+ postacc_code = '', base_class = 'MemoryDisp32',
+ decode_template = BasicDecode, exec_template_base = ''):
+ # Make sure flags are in lists (convert to lists if not).
+ mem_flags = makeList(mem_flags)
+ inst_flags = makeList(inst_flags)
+
+ # add hook to get effective addresses into execution trace output.
+ ea_code += '\nif (traceData) { traceData->setAddr(EA); }\n'
+
+ # generate code block objects
+ ea_cblk = CodeBlock(ea_code)
+ memacc_cblk = CodeBlock(memacc_code)
+ postacc_cblk = CodeBlock(postacc_code)
+
+ # Some CPU models execute the memory operation as an atomic unit,
+ # while others want to separate them into an effective address
+ # computation and a memory access operation. As a result, we need
+ # to generate three StaticInst objects. Note that the latter two
+ # are nested inside the larger "atomic" one.
+
+ # generate InstObjParams for EAComp object
+ ea_iop = InstObjParams(name, Name, base_class, ea_cblk, inst_flags)
+
+ # generate InstObjParams for MemAcc object
+ memacc_iop = InstObjParams(name, Name, base_class, memacc_cblk, inst_flags)
+ # in the split execution model, the MemAcc portion is responsible
+ # for the post-access code.
+ memacc_iop.postacc_code = postacc_cblk.code
+
+ # generate InstObjParams for InitiateAcc, CompleteAcc object
+ # The code used depends on the template being used
+ if (exec_template_base == 'Load'):
+ initiateacc_cblk = CodeBlock(ea_code + memacc_code)
+ completeacc_cblk = CodeBlock(memacc_code + postacc_code)
+ elif (exec_template_base.startswith('Store')):
+ initiateacc_cblk = CodeBlock(ea_code + memacc_code)
+ completeacc_cblk = CodeBlock(postacc_code)
+ else:
+ initiateacc_cblk = ''
+ completeacc_cblk = ''
+
+ initiateacc_iop = InstObjParams(name, Name, base_class, initiateacc_cblk,
+ inst_flags)
+
+ completeacc_iop = InstObjParams(name, Name, base_class, completeacc_cblk,
+ inst_flags)
+
+ if (exec_template_base == 'Load'):
+ initiateacc_iop.ea_code = ea_cblk.code
+ initiateacc_iop.memacc_code = memacc_cblk.code
+ completeacc_iop.memacc_code = memacc_cblk.code
+ completeacc_iop.postacc_code = postacc_cblk.code
+ elif (exec_template_base.startswith('Store')):
+ initiateacc_iop.ea_code = ea_cblk.code
+ initiateacc_iop.memacc_code = memacc_cblk.code
+ completeacc_iop.postacc_code = postacc_cblk.code
+
+ # generate InstObjParams for unified execution
+ cblk = CodeBlock(ea_code + memacc_code + postacc_code)
+ iop = InstObjParams(name, Name, base_class, cblk, inst_flags)
+
+ iop.ea_constructor = ea_cblk.constructor
+ iop.ea_code = ea_cblk.code
+ iop.memacc_constructor = memacc_cblk.constructor
+ iop.memacc_code = memacc_cblk.code
+ iop.postacc_code = postacc_cblk.code
+
+ if mem_flags:
+ s = '\n\tmemAccessFlags = ' + string.join(mem_flags, '|') + ';'
+ iop.constructor += s
+ memacc_iop.constructor += s
+
+ # select templates
+
+ # define aliases... most StoreCond templates are the same as the
+ # corresponding Store templates (only CompleteAcc is different).
+ StoreCondMemAccExecute = StoreMemAccExecute
+ StoreCondExecute = StoreExecute
+ StoreCondInitiateAcc = StoreInitiateAcc
+
+ memAccExecTemplate = eval(exec_template_base + 'MemAccExecute')
+ fullExecTemplate = eval(exec_template_base + 'Execute')
+ initiateAccTemplate = eval(exec_template_base + 'InitiateAcc')
+ completeAccTemplate = eval(exec_template_base + 'CompleteAcc')
+
+ # (header_output, decoder_output, decode_block, exec_output)
+ return (LoadStoreDeclare.subst(iop), LoadStoreConstructor.subst(iop),
+ decode_template.subst(iop),
+ EACompExecute.subst(ea_iop)
+ + memAccExecTemplate.subst(memacc_iop)
+ + fullExecTemplate.subst(iop)
+ + initiateAccTemplate.subst(initiateacc_iop)
+ + completeAccTemplate.subst(completeacc_iop))
+}};
+
+
+def format LoadOrNop(memacc_code, ea_code = {{ EA = Rb + disp; }},
+ mem_flags = [], inst_flags = []) {{
+ (header_output, decoder_output, decode_block, exec_output) = \
+ LoadStoreBase(name, Name, ea_code, memacc_code, mem_flags, inst_flags,
+ decode_template = LoadNopCheckDecode,
+ exec_template_base = 'Load')
+}};
+
+
+// Note that the flags passed in apply only to the prefetch version
+def format LoadOrPrefetch(memacc_code, ea_code = {{ EA = Rb + disp; }},
+ mem_flags = [], pf_flags = [], inst_flags = []) {{
+ # declare the load instruction object and generate the decode block
+ (header_output, decoder_output, decode_block, exec_output) = \
+ LoadStoreBase(name, Name, ea_code, memacc_code, mem_flags, inst_flags,
+ decode_template = LoadPrefetchCheckDecode,
+ exec_template_base = 'Load')
+
+ # Declare the prefetch instruction object.
+
+ # Make sure flag args are lists so we can mess with them.
+ mem_flags = makeList(mem_flags)
+ pf_flags = makeList(pf_flags)
+ inst_flags = makeList(inst_flags)
+
+ pf_mem_flags = mem_flags + pf_flags + ['NO_FAULT']
+ pf_inst_flags = inst_flags + ['IsMemRef', 'IsLoad',
+ 'IsDataPrefetch', 'MemReadOp']
+
+ (pf_header_output, pf_decoder_output, _, pf_exec_output) = \
+ LoadStoreBase(name, Name + 'Prefetch', ea_code,
+ 'xc->prefetch(EA, memAccessFlags);',
+ pf_mem_flags, pf_inst_flags, exec_template_base = 'Misc')
+
+ header_output += pf_header_output
+ decoder_output += pf_decoder_output
+ exec_output += pf_exec_output
+}};
+
+
+def format Store(memacc_code, ea_code = {{ EA = Rb + disp; }},
+ mem_flags = [], inst_flags = []) {{
+ (header_output, decoder_output, decode_block, exec_output) = \
+ LoadStoreBase(name, Name, ea_code, memacc_code, mem_flags, inst_flags,
+ exec_template_base = 'Store')
+}};
+
+
+def format StoreCond(memacc_code, postacc_code,
+ ea_code = {{ EA = Rb + disp; }},
+ mem_flags = [], inst_flags = []) {{
+ (header_output, decoder_output, decode_block, exec_output) = \
+ LoadStoreBase(name, Name, ea_code, memacc_code, mem_flags, inst_flags,
+ postacc_code, exec_template_base = 'StoreCond')
+}};
+
+
+// Use 'MemoryNoDisp' as base: for wh64, fetch, ecb
+def format MiscPrefetch(ea_code, memacc_code,
+ mem_flags = [], inst_flags = []) {{
+ (header_output, decoder_output, decode_block, exec_output) = \
+ LoadStoreBase(name, Name, ea_code, memacc_code, mem_flags, inst_flags,
+ base_class = 'MemoryNoDisp', exec_template_base = 'Misc')
+}};
+
+
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