src/cpu/TimingExpr.py

   1 # Copyright (c) 2013-2014 ARM Limited
   2 # All rights reserved.
   3 #
   4 # The license below extends only to copyright in the software and shall
   5 # not be construed as granting a license to any other intellectual
   6 # property including but not limited to intellectual property relating
   7 # to a hardware implementation of the functionality of the software
   8 # licensed hereunder.  You may use the software subject to the license
   9 # terms below provided that you ensure that this notice is replicated
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  11 # modified or unmodified, in source code or in binary form.
  12 #
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  14 # modification, are permitted provided that the following conditions are
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  35
  36 from m5.params import *
  37 from m5.SimObject import SimObject
  38
  39 # These classes define an expression language over uint64_t with only
  40 # a few operators.  This can be used to form expressions for the extra
  41 # delay required in variable execution time instructions.
  42 #
  43 # Expressions, in evaluation, will have access to the ThreadContext and
  44 # a StaticInst
  45
  46 class TimingExpr(SimObject):
  47     type = 'TimingExpr'
  48     cxx_header = 'cpu/timing_expr.hh'
  49     abstract = True;
  50
  51 class TimingExprLiteral(TimingExpr):
  52     """Literal 64 bit unsigned value"""
  53     type = 'TimingExprLiteral'
  54     cxx_header = 'cpu/timing_expr.hh'
  55
  56     value = Param.UInt64("literal value")
  57
  58     def set_params(self, value):
  59         self.value = value
  60         return self
  61
  62 class TimingExpr0(TimingExprLiteral):
  63     """Convenient 0"""
  64     value = 0
  65
  66 class TimingExprSrcReg(TimingExpr):
  67     """Find the source register number from the current inst"""
  68     type = 'TimingExprSrcReg'
  69     cxx_header = 'cpu/timing_expr.hh'
  70
  71     # index = Param.Unsigned("index into inst src regs")
  72     index = Param.Unsigned("index into inst src regs")
  73
  74     def set_params(self, index):
  75         self.index = index
  76         return self
  77
  78 class TimingExprReadIntReg(TimingExpr):
  79     """Read an architectural register"""
  80     type = 'TimingExprReadIntReg'
  81     cxx_header = 'cpu/timing_expr.hh'
  82
  83     reg = Param.TimingExpr("register raw index to read")
  84
  85     def set_params(self, reg):
  86         self.reg = reg
  87         return self
  88
  89 class TimingExprLet(TimingExpr):
  90     """Block of declarations"""
  91     type = 'TimingExprLet'
  92     cxx_header = 'cpu/timing_expr.hh'
  93
  94     defns = VectorParam.TimingExpr("expressions for bindings")
  95     expr = Param.TimingExpr("body expression")
  96
  97     def set_params(self, defns, expr):
  98         self.defns = defns
  99         self.expr = expr
 100         return self
 101
 102 class TimingExprRef(TimingExpr):
 103     """Value of a bound sub-expression"""
 104     type = 'TimingExprRef'
 105     cxx_header = 'cpu/timing_expr.hh'
 106
 107     index = Param.Unsigned("expression index")
 108
 109     def set_params(self, index):
 110         self.index = index
 111         return self
 112
 113 class TimingExprOp(Enum):
 114     vals = [
 115         'timingExprAdd', 'timingExprSub',
 116         'timingExprUMul', 'timingExprUDiv',
 117         'timingExprSMul', 'timingExprSDiv',
 118         'timingExprUCeilDiv', # Unsigned divide rounding up
 119         'timingExprEqual', 'timingExprNotEqual',
 120         'timingExprULessThan',
 121         'timingExprUGreaterThan',
 122         'timingExprSLessThan',
 123         'timingExprSGreaterThan',
 124         'timingExprInvert',
 125         'timingExprNot',
 126         'timingExprAnd',
 127         'timingExprOr',
 128         'timingExprSizeInBits',
 129         'timingExprSignExtend32To64',
 130         'timingExprAbs'
 131         ]
 132
 133 class TimingExprUn(TimingExpr):
 134     """Unary operator"""
 135     type = 'TimingExprUn'
 136     cxx_header = 'cpu/timing_expr.hh'
 137
 138     op = Param.TimingExprOp("operator")
 139     arg = Param.TimingExpr("expression")
 140
 141     def set_params(self, op, arg):
 142         self.op = op
 143         self.arg = arg
 144         return self
 145
 146 class TimingExprBin(TimingExpr):
 147     """Binary operator"""
 148     type = 'TimingExprBin'
 149     cxx_header = 'cpu/timing_expr.hh'
 150
 151     op = Param.TimingExprOp("operator")
 152     left = Param.TimingExpr("LHS expression")
 153     right = Param.TimingExpr("RHS expression")
 154
 155     def set_params(self, op, left, right):
 156         self.op = op
 157         self.left = left
 158         self.right = right
 159         return self
 160
 161 class TimingExprIf(TimingExpr):
 162     """If-then-else operator"""
 163     type = 'TimingExprIf'
 164     cxx_header = 'cpu/timing_expr.hh'
 165
 166     cond = Param.TimingExpr("condition expression")
 167     trueExpr = Param.TimingExpr("true expression")
 168     falseExpr = Param.TimingExpr("false expression")
 169
 170     def set_params(self, cond, trueExpr, falseExpr):
 171         self.cond = cond
 172         self.trueExpr = trueExpr
 173         self.falseExpr = falseExpr
 174         return self