diff options
Diffstat (limited to 'src/arch/mips/isa/formats/branch.isa')
-rw-r--r-- | src/arch/mips/isa/formats/branch.isa | 160 |
1 files changed, 43 insertions, 117 deletions
diff --git a/src/arch/mips/isa/formats/branch.isa b/src/arch/mips/isa/formats/branch.isa index 8cfa37a20..e8843da03 100644 --- a/src/arch/mips/isa/formats/branch.isa +++ b/src/arch/mips/isa/formats/branch.isa @@ -68,29 +68,6 @@ output header {{ }; /** - * Base class for branch likely branches (PC-relative control transfers), - */ - class BranchLikely : public PCDependentDisassembly - { - protected: - /// target address (signed) Displacement . - int32_t disp; - - /// Constructor. - BranchLikely(const char *mnem, MachInst _machInst, OpClass __opClass) - : PCDependentDisassembly(mnem, _machInst, __opClass), - disp(OFFSET << 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 Mips ISA, these are always unconditional. */ @@ -111,7 +88,7 @@ output header {{ { } - Addr branchTarget(ExecContext *xc) const; + Addr branchTarget(ThreadContext *tc) const; std::string generateDisassembly(Addr pc, const SymbolTable *symtab) const; @@ -126,16 +103,10 @@ output decoder {{ } Addr - BranchLikely::branchTarget(Addr branchPC) const + Jump::branchTarget(ThreadContext *tc) const { - return branchPC + 4 + disp; - } - - Addr - Jump::branchTarget(ExecContext *xc) const - { - Addr NPC = xc->readPC() + 4; - uint64_t Rb = xc->readIntReg(_srcRegIdx[0]); + Addr NPC = tc->readPC() + 4; + uint64_t Rb = tc->readIntReg(_srcRegIdx[0]); return (Rb & ~3) | (NPC & 1); } @@ -171,49 +142,12 @@ output decoder {{ // unconditional branches) if (_numSrcRegs == 1) { printReg(ss, _srcRegIdx[0]); - ss << ","; + ss << ", "; } else if(_numSrcRegs == 2) { printReg(ss, _srcRegIdx[0]); - ss << ","; + ss << ", "; printReg(ss, _srcRegIdx[1]); - ss << ","; - } - - Addr target = pc + 4 + disp; - - std::string str; - if (symtab && symtab->findSymbol(target, str)) - ss << str; - else - ccprintf(ss, "0x%x", target); - - string inst_name = mnemonic; - - if (inst_name.substr(inst_name.length()-2,inst_name.length()) == "al"){ - ccprintf(ss, " (r31=0x%x)",pc+8); - } - - return ss.str(); - } - - std::string - BranchLikely::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 << ","; + ss << ", "; } Addr target = pc + 4 + disp; @@ -247,72 +181,64 @@ output decoder {{ printReg(ss, _srcRegIdx[0]); } else if(_numSrcRegs == 2) { printReg(ss, _srcRegIdx[0]); - ss << ","; + ss << ", "; printReg(ss, _srcRegIdx[1]); - } else { - panic(">= 3 Source Registers!!!"); } return ss.str(); } }}; -def format Branch(code,*flags) {{ - #Add Link Code if Link instruction - strlen = len(name) - if name[strlen-2:] == 'al': - code += 'R31 = NNPC;\n' +def format Branch(code,*opt_flags) {{ + not_taken_code = ' NNPC = NNPC;\n' + not_taken_code += '} \n' + + #Build Instruction Flags + #Use Link & Likely Flags to Add Link/Condition Code + inst_flags = ('IsDirectControl', ) + for x in opt_flags: + if x == 'Link': + code += 'R31 = NNPC;\n' + elif x == 'Likely': + not_taken_code = ' NPC = NNPC;\n' + not_taken_code += ' NNPC = NNPC + 4;\n' + not_taken_code += '} \n' + inst_flags = ('IsCondDelaySlot', ) + else: + inst_flags += (x, ) + + if 'cond == 1' in code: + inst_flags += ('IsCondControl', ) + else: + inst_flags += ('IsUncondControl', ) #Condition code code = 'bool cond;\n' + code code += 'if (cond) {\n' code += ' NNPC = NPC + disp;\n' code += '} else {\n' - code += ' NNPC = NNPC;\n' - code += '} \n' - - iop = InstObjParams(name, Name, 'Branch', CodeBlock(code), - ('IsDirectControl', 'IsCondControl')) + code += not_taken_code + iop = InstObjParams(name, Name, 'Branch', CodeBlock(code), inst_flags) header_output = BasicDeclare.subst(iop) decoder_output = BasicConstructor.subst(iop) decode_block = BasicDecode.subst(iop) exec_output = BasicExecute.subst(iop) }}; - -def format BranchLikely(code,*flags) {{ - #Add Link Code if Link instruction - strlen = len(name) - if name[strlen-3:] == 'all': - code += 'R31 = NNPC;\n' - - #Condition code - code = 'bool cond;\n' + code - code += 'if (cond) {' - code += 'NNPC = NPC + disp;\n' - code += '} \n' - - - iop = InstObjParams(name, Name, 'Branch', CodeBlock(code), - ('IsDirectControl', 'IsCondControl','IsCondDelaySlot')) - - header_output = BasicDeclare.subst(iop) - decoder_output = BasicConstructor.subst(iop) - decode_block = BasicDecode.subst(iop) - exec_output = BasicExecute.subst(iop) -}}; - -def format Jump(code,*flags) {{ - #Add Link Code if Link instruction - strlen = len(name) - if strlen > 1 and name[1:] == 'al': +def format Jump(code, *opt_flags) {{ + #Build Instruction Flags + #Use Link Flag to Add Link Code + inst_flags = ('IsIndirectControl', 'IsUncondControl') + for x in opt_flags: + if x == 'Link': code = 'R31 = NNPC;\n' + code + elif x == 'ClearHazards': + code += '/* Code Needed to Clear Execute & Inst Hazards */\n' + else: + inst_flags += (x, ) - - iop = InstObjParams(name, Name, 'Jump', CodeBlock(code),\ - ('IsIndirectControl', 'IsUncondControl')) - + iop = InstObjParams(name, Name, 'Jump', CodeBlock(code), inst_flags) header_output = BasicDeclare.subst(iop) decoder_output = BasicConstructor.subst(iop) decode_block = BasicDecode.subst(iop) |