From 4c9b023a7afec8ba3a89736a01f445fc3e6adb05 Mon Sep 17 00:00:00 2001 From: Gabe Black Date: Tue, 7 Dec 2010 23:08:05 -0800 Subject: ISA: Get the parser to support pc state components more elegantly. --- src/arch/isa_parser.py | 113 +++++++++++++++++++++++++++++++++---------------- 1 file changed, 77 insertions(+), 36 deletions(-) (limited to 'src') diff --git a/src/arch/isa_parser.py b/src/arch/isa_parser.py index 4c23529f0..2a03f1968 100755 --- a/src/arch/isa_parser.py +++ b/src/arch/isa_parser.py @@ -171,6 +171,8 @@ class Template(object): operands = SubOperandList(self.parser, compositeCode, d.operands) myDict['op_decl'] = operands.concatAttrStrings('op_decl') + if operands.readPC or operands.setPC: + myDict['op_decl'] += 'TheISA::PCState __parserAutoPCState;\n' is_src = lambda op: op.is_src is_dest = lambda op: op.is_dest @@ -181,7 +183,25 @@ class Template(object): operands.concatSomeAttrStrings(is_dest, 'op_dest_decl') myDict['op_rd'] = operands.concatAttrStrings('op_rd') - myDict['op_wb'] = operands.concatAttrStrings('op_wb') + if operands.readPC: + myDict['op_rd'] = '__parserAutoPCState = xc->pcState();\n' + \ + myDict['op_rd'] + + # Compose the op_wb string. If we're going to write back the + # PC state because we changed some of its elements, we'll need to + # do that as early as possible. That allows later uncoordinated + # modifications to the PC to layer appropriately. + reordered = list(operands.items) + reordered.reverse() + op_wb_str = '' + pcWbStr = 'xc->pcState(__parserAutoPCState);\n' + for op_desc in reordered: + if op_desc.isPCPart() and op_desc.is_dest: + op_wb_str = op_desc.op_wb + pcWbStr + op_wb_str + pcWbStr = '' + else: + op_wb_str = op_desc.op_wb + op_wb_str + myDict['op_wb'] = op_wb_str if d.operands.memOperand: myDict['mem_acc_size'] = d.operands.memOperand.mem_acc_size @@ -433,11 +453,12 @@ class Operand(object): # extension, if one was explicitly provided, or the default. if ext: self.eff_ext = ext - else: + elif hasattr(self, 'dflt_ext'): self.eff_ext = self.dflt_ext - self.size, self.ctype, self.is_signed = \ - parser.operandTypeMap[self.eff_ext] + if hasattr(self, 'eff_ext'): + self.size, self.ctype, self.is_signed = \ + parser.operandTypeMap[self.eff_ext] # note that mem_acc_size is undefined for non-mem operands... # template must be careful not to use it if it doesn't apply. @@ -486,6 +507,12 @@ class Operand(object): def isControlReg(self): return 0 + def isPCState(self): + return 0 + + def isPCPart(self): + return self.isPCState() and self.reg_spec + def getFlags(self): # note the empty slice '[:]' gives us a copy of self.flags[0] # instead of a reference to it @@ -686,38 +713,31 @@ class PCStateOperand(Operand): return '' def makeRead(self): - return '%s = xc->pcState();\n' % self.base_name + if self.reg_spec: + # A component of the PC state. + return '%s = __parserAutoPCState.%s();\n' % \ + (self.base_name, self.reg_spec) + else: + # The whole PC state itself. + return '%s = xc->pcState();\n' % self.base_name def makeWrite(self): - return 'xc->pcState(%s);\n' % self.base_name + if self.reg_spec: + # A component of the PC state. + return '__parserAutoPCState.%s(%s);\n' % \ + (self.reg_spec, self.base_name) + else: + # The whole PC state itself. + return 'xc->pcState(%s);\n' % self.base_name def makeDecl(self): - return 'TheISA::PCState ' + self.base_name + ' M5_VAR_USED;\n'; - -class PCOperand(Operand): - def makeConstructor(self): - return '' - - def makeRead(self): - return '%s = xc->instAddr();\n' % self.base_name - -class UPCOperand(Operand): - def makeConstructor(self): - return '' - - def makeRead(self): - if self.read_code != None: - return self.buildReadCode('microPC') - return '%s = xc->microPC();\n' % self.base_name - -class NPCOperand(Operand): - def makeConstructor(self): - return '' + ctype = 'TheISA::PCState' + if self.isPCPart(): + ctype = self.ctype + return "%s %s;\n" % (ctype, self.base_name) - def makeRead(self): - if self.read_code != None: - return self.buildReadCode('nextInstAddr') - return '%s = xc->nextInstAddr();\n' % self.base_name + def isPCState(self): + return 1 class OperandList(object): '''Find all the operands in the given code block. Returns an operand @@ -868,7 +888,25 @@ class SubOperandList(OperandList): next_pos = match.end() self.sort() self.memOperand = None + # Whether the whole PC needs to be read so parts of it can be accessed + self.readPC = False + # Whether the whole PC needs to be written after parts of it were + # changed + self.setPC = False + # Whether this instruction manipulates the whole PC or parts of it. + # Mixing the two is a bad idea and flagged as an error. + self.pcPart = None for op_desc in self.items: + if op_desc.isPCPart(): + self.readPC = True + if op_desc.is_dest: + self.setPC = True + if op_desc.isPCState(): + if self.pcPart is not None: + if self.pcPart and not op_desc.isPCPart() or \ + not self.pcPart and op_desc.isPCPart(): + error("Mixed whole and partial PC state operands.") + self.pcPart = op_desc.isPCPart() if op_desc.isMem(): if self.memOperand: error("Code block has more than one memory operand.") @@ -1847,8 +1885,6 @@ StaticInstPtr 'error: too many attributes for operand "%s"' % base_cls_name) - (dflt_size, dflt_ctype, dflt_is_signed) = \ - self.operandTypeMap[dflt_ext] # Canonical flag structure is a triple of lists, where each list # indicates the set of flags implied by this operand always, when # used as a source, and when used as a dest, respectively. @@ -1871,9 +1907,14 @@ StaticInstPtr makeList(src_flags), makeList(dest_flags)) # Accumulate attributes of new operand class in tmp_dict tmp_dict = {} - for attr in ('dflt_ext', 'reg_spec', 'flags', 'sort_pri', - 'dflt_size', 'dflt_ctype', 'dflt_is_signed', - 'read_code', 'write_code'): + attrList = ['reg_spec', 'flags', 'sort_pri', + 'read_code', 'write_code'] + if dflt_ext: + (dflt_size, dflt_ctype, dflt_is_signed) = \ + self.operandTypeMap[dflt_ext] + attrList.extend(['dflt_size', 'dflt_ctype', + 'dflt_is_signed', 'dflt_ext']) + for attr in attrList: tmp_dict[attr] = eval(attr) tmp_dict['base_name'] = op_name # New class name will be e.g. "IntReg_Ra" -- cgit v1.2.3