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1 See ../README.
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2
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3 The frontend is written in C++. It can only be used in conjunction
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4 with a full compiler backend. Currently the backend interface has
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5 been implemented with GCC (known as gccgo) and with LLVM (known as
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6 GoLLVM).
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7
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8 The frontend lexes and parses the input into an IR specific to this
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9 frontend known as gogo. It then runs a series of passes over the
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10 code.
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11
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12 Finally it converts gogo to the backend IR. This is done via the
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13 interface described in backend.h. The backend must implement that
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14 interface. When used with GCC, the interface is implemented in
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15 gcc/go/go-gcc.cc.
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16
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17 Source locations are represented using the interface described in
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18 go-linemap.h. The backend is expected to provide a header file
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19 go-location.h that defines a Location type.
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20
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21 The frontend does not start by itself. It expects something to call
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22 go_create_gogo passing in a Backend and a Linemap, as well as other
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23 options. Then it expects something to call go_parse_input_files
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24 passing in the input files. Finally, a call to go_write_globals will
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25 cause all global definitions to be written out via the Backend
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26 interface.
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27
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28 The backend is expected to provide the functions defined at the
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29 bottom of go-diagnostics.h: go_be_error_at, etc. These will be used
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30 for error messages.
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31
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32 This compiler works, but the code is a work in progress. The frontend
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33 pays little attention to its memory usage and rarely frees any memory.
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34 The code could use a general cleanup which we have not had time to do.
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35
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36 Contributing
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37 =============
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38
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39 To contribute patches to the files in this directory, please see
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40 https://golang.org/doc/gccgo_contribute.html .
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41
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42 The master copy of these files is hosted at
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43 https://go.googlesource.com/gofrontend . There is a mirror at
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44 https://github.com/golang/gofrontend . Changes to these files require
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45 signing a Google contributor license agreement. If you are the
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46 copyright holder, you will need to agree to the individual contributor
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47 https://cla.developers.google.com/about/google-individual . This
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48 agreement can be completed online.
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49
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50 If your organization is the copyright holder, the organization will
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51 need to agree to the corporate contributor license agreement at
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52 https://cla.developers.google.com/about/google-corporate .
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53
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54 If the copyright holder for your code has already completed the
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55 agreement in connection with another Google open source project, it
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56 does not need to be completed again.
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