| // Copyright (c) 2006-2007 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: Gabe Black |
| // Steve Reinhardt |
| |
| //////////////////////////////////////////////////////////////////// |
| // |
| // Branch instructions |
| // |
| |
| output header {{ |
| /** |
| * Base class for branch operations. |
| */ |
| class Branch : public SparcStaticInst |
| { |
| protected: |
| // Constructor |
| Branch(const char *mnem, ExtMachInst _machInst, OpClass __opClass) : |
| SparcStaticInst(mnem, _machInst, __opClass) |
| { |
| } |
| |
| std::string generateDisassembly(Addr pc, |
| const SymbolTable *symtab) const; |
| }; |
| |
| /** |
| * Base class for branch operations with an immediate displacement. |
| */ |
| class BranchDisp : public Branch |
| { |
| protected: |
| // Constructor |
| BranchDisp(const char *mnem, ExtMachInst _machInst, |
| OpClass __opClass) : |
| Branch(mnem, _machInst, __opClass) |
| { |
| } |
| |
| std::string generateDisassembly(Addr pc, |
| const SymbolTable *symtab) const; |
| |
| int32_t disp; |
| }; |
| |
| /** |
| * Base class for branches with n bit displacements. |
| */ |
| template<int bits> |
| class BranchNBits : public BranchDisp |
| { |
| protected: |
| // Constructor |
| BranchNBits(const char *mnem, ExtMachInst _machInst, |
| OpClass __opClass) : |
| BranchDisp(mnem, _machInst, __opClass) |
| { |
| disp = sext<bits + 2>((_machInst & mask(bits)) << 2); |
| } |
| }; |
| |
| /** |
| * Base class for 16bit split displacements. |
| */ |
| class BranchSplit : public BranchDisp |
| { |
| protected: |
| // Constructor |
| BranchSplit(const char *mnem, ExtMachInst _machInst, |
| OpClass __opClass) : |
| BranchDisp(mnem, _machInst, __opClass) |
| { |
| disp = sext<18>((D16HI << 16) | (D16LO << 2)); |
| } |
| }; |
| |
| /** |
| * Base class for branches that use an immediate and a register to |
| * compute their displacements. |
| */ |
| class BranchImm13 : public Branch |
| { |
| protected: |
| // Constructor |
| BranchImm13(const char *mnem, ExtMachInst _machInst, OpClass __opClass) : |
| Branch(mnem, _machInst, __opClass), imm(sext<13>(SIMM13)) |
| { |
| } |
| |
| std::string generateDisassembly(Addr pc, |
| const SymbolTable *symtab) const; |
| |
| int32_t imm; |
| }; |
| }}; |
| |
| output decoder {{ |
| |
| template class BranchNBits<19>; |
| |
| template class BranchNBits<22>; |
| |
| template class BranchNBits<30>; |
| |
| std::string |
| Branch::generateDisassembly(Addr pc, const SymbolTable *symtab) const |
| { |
| std::stringstream response; |
| |
| printMnemonic(response, mnemonic); |
| printRegArray(response, _srcRegIdx, _numSrcRegs); |
| if (_numDestRegs && _numSrcRegs) |
| response << ", "; |
| printDestReg(response, 0); |
| |
| return response.str(); |
| } |
| |
| std::string |
| BranchImm13::generateDisassembly(Addr pc, |
| const SymbolTable *symtab) const |
| { |
| std::stringstream response; |
| |
| printMnemonic(response, mnemonic); |
| printRegArray(response, _srcRegIdx, _numSrcRegs); |
| if (_numSrcRegs > 0) |
| response << ", "; |
| ccprintf(response, "0x%x", imm); |
| if (_numDestRegs > 0) |
| response << ", "; |
| printDestReg(response, 0); |
| |
| return response.str(); |
| } |
| |
| std::string |
| BranchDisp::generateDisassembly(Addr pc, |
| const SymbolTable *symtab) const |
| { |
| std::stringstream response; |
| std::string symbol; |
| Addr symbolAddr; |
| |
| Addr target = disp + pc; |
| |
| printMnemonic(response, mnemonic); |
| ccprintf(response, "0x%x", target); |
| |
| if (symtab && |
| symtab->findNearestSymbol(target, symbol, symbolAddr)) { |
| ccprintf(response, " <%s", symbol); |
| if (symbolAddr != target) |
| ccprintf(response, "+%d>", target - symbolAddr); |
| else |
| ccprintf(response, ">"); |
| } |
| |
| return response.str(); |
| } |
| }}; |
| |
| def template JumpExecute {{ |
| Fault %(class_name)s::execute(ExecContext *xc, |
| Trace::InstRecord *traceData) const |
| { |
| // Attempt to execute the instruction |
| Fault fault = NoFault; |
| |
| %(op_decl)s; |
| %(op_rd)s; |
| |
| %(code)s; |
| |
| if (fault == NoFault) { |
| // Write the resulting state to the execution context |
| %(op_wb)s; |
| } |
| |
| return fault; |
| } |
| }}; |
| |
| def template BranchExecute {{ |
| Fault |
| %(class_name)s::execute(ExecContext *xc, |
| Trace::InstRecord *traceData) const |
| { |
| // Attempt to execute the instruction |
| Fault fault = NoFault; |
| |
| %(op_decl)s; |
| %(op_rd)s; |
| |
| if (%(cond)s) { |
| %(code)s; |
| } else { |
| %(fail)s; |
| } |
| |
| if (fault == NoFault) { |
| // Write the resulting state to the execution context |
| %(op_wb)s; |
| } |
| |
| return fault; |
| } |
| }}; |
| |
| def template BranchDecode {{ |
| if (A) |
| return new %(class_name)sAnnul("%(mnemonic)s,a", machInst); |
| else |
| return new %(class_name)s("%(mnemonic)s", machInst); |
| }}; |
| |
| // Primary format for branch instructions: |
| def format Branch(code, *opt_flags) {{ |
| code = 'NNPC = NNPC;\n' + code |
| (usesImm, code, immCode, |
| rString, iString) = splitOutImm(code) |
| iop = InstObjParams(name, Name, 'Branch', code, opt_flags) |
| header_output = BasicDeclare.subst(iop) |
| decoder_output = BasicConstructor.subst(iop) |
| exec_output = JumpExecute.subst(iop) |
| if usesImm: |
| imm_iop = InstObjParams(name, Name + 'Imm', 'BranchImm' + iString, |
| immCode, opt_flags) |
| header_output += BasicDeclare.subst(imm_iop) |
| decoder_output += BasicConstructor.subst(imm_iop) |
| exec_output += JumpExecute.subst(imm_iop) |
| decode_block = ROrImmDecode.subst(iop) |
| else: |
| decode_block = BasicDecode.subst(iop) |
| }}; |
| |
| let {{ |
| def doBranch(name, Name, base, cond, |
| code, annul_code, fail, annul_fail, opt_flags): |
| #@todo: add flags and branchTarget() for DirectCntrl branches |
| # the o3 model can take advantage of this annotation if |
| # done correctly |
| |
| iop = InstObjParams(name, Name, base, |
| {"code": code, |
| "fail": fail, |
| "cond": cond |
| }, |
| opt_flags) |
| header_output = BasicDeclareWithMnemonic.subst(iop) |
| decoder_output = BasicConstructorWithMnemonic.subst(iop) |
| exec_output = BranchExecute.subst(iop) |
| if annul_code == "None": |
| decode_block = BasicDecodeWithMnemonic.subst(iop) |
| else: |
| decode_block = BranchDecode.subst(iop) |
| |
| if annul_code != "None": |
| iop = InstObjParams(name + ',a', Name + 'Annul', base, |
| {"code": annul_code, |
| "fail": annul_fail, |
| "cond": cond |
| }, |
| opt_flags) |
| header_output += BasicDeclareWithMnemonic.subst(iop) |
| decoder_output += BasicConstructorWithMnemonic.subst(iop) |
| exec_output += BranchExecute.subst(iop) |
| return (header_output, decoder_output, exec_output, decode_block) |
| |
| def doCondBranch(name, Name, base, cond, code, opt_flags): |
| opt_flags += ('IsCondControl', ) |
| return doBranch(name, Name, base, cond, code, code, |
| 'NNPC = NNPC; NPC = NPC;\n', |
| 'NNPC = NPC + 8; NPC = NPC + 4;\n', |
| opt_flags) |
| |
| def doUncondBranch(name, Name, base, code, annul_code, opt_flags): |
| opt_flags += ('IsUncondControl', ) |
| return doBranch(name, Name, base, "true", code, annul_code, |
| ";", ";", opt_flags) |
| |
| default_branch_code = 'NNPC = PC + disp;\n' |
| }}; |
| |
| // Format for branch instructions with n bit displacements: |
| def format BranchN(bits, code=default_branch_code, |
| test=None, annul_code=None, *opt_flags) {{ |
| if code == "default_branch_code": |
| code = default_branch_code |
| if test != "None": |
| (header_output, |
| decoder_output, |
| exec_output, |
| decode_block) = doCondBranch(name, Name, |
| "BranchNBits<%d>" % bits, test, code, opt_flags) |
| else: |
| (header_output, |
| decoder_output, |
| exec_output, |
| decode_block) = doUncondBranch(name, Name, |
| "BranchNBits<%d>" % bits, code, annul_code, opt_flags) |
| }}; |
| |
| // Format for branch instructions with split displacements: |
| def format BranchSplit(code=default_branch_code, |
| test=None, annul_code=None, *opt_flags) {{ |
| if code == "default_branch_code": |
| code = default_branch_code |
| if test != "None": |
| (header_output, |
| decoder_output, |
| exec_output, |
| decode_block) = doCondBranch(name, Name, |
| "BranchSplit", test, code, opt_flags) |
| else: |
| (header_output, |
| decoder_output, |
| exec_output, |
| decode_block) = doUncondBranch(name, Name, |
| "BranchSplit", code, annul_code, opt_flags) |
| }}; |
| |
