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310
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1
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2 Utilities
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3 =========
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4
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5 Hexfile manipulation
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6 --------------------
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7
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8
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9 .. autoclass:: utils.HexFile
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10
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11
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12 >>> from utils import HexFile
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13 >>> h = HexFile()
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14 >>> h.dump()
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15 Hexfile containing 0 bytes
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16 >>> h.addRegion(0, bytes([1,2,3]))
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17 >>> h
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18 Hexfile containing 3 bytes
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19
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20
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319
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21 Yacc
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22 ----
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23
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24 .. automodule:: yacc
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25
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26
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27 Burg
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28 ----
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29
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30 .. automodule:: pyburg
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31
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381
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32
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33 Machine descriptions
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34 --------------------
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35
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36 There are some attempts made already to describe machines in a Domain
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37 Specific Language (DSL). Examples of these are:
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38 - Tablegen (llvm)
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39 - cgen (gnu)
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40 - LISA (Aachen)
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41 - nML (Berlin)
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42 - SLED (Specifying representations of machine instructions (norman ramsey and Mary F. Fernandez))
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43
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44
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45 The goal of a machine description file is to describe a file and generate
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46 tools like assemblers, disassemblers, linkers, debuggers and simulators.
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47
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48 Advantage of using this approach is that porting these tools is a semi automated
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49 process. Rewriting all of these tools from scratch is tedious and errorprone.
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50
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51 Concepts to use in this language:
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52 - Single stream of instructions
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53 - State stored in memory
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54 - Pipelining
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55 - Instruction semantics
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56
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57 Each instruction has the following properties:
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58 - Bit representation
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59 - Assembly language representation
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60 - Semantic action
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61
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62 Optionally a description in terms of compiler code generation can be attached
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63 to this. But perhaps this clutters the description too much and we need to put
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64 it elsewhere.
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65
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66
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67 The description language can help to expand these descriptions by expanding
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68 the permutations.
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69
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70
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71
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