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diff --git a/contrib/llvm/tools/llvmc/doc/LLVMC-Reference.rst b/contrib/llvm/tools/llvmc/doc/LLVMC-Reference.rst deleted file mode 100644 index d160e75..0000000 --- a/contrib/llvm/tools/llvmc/doc/LLVMC-Reference.rst +++ /dev/null @@ -1,839 +0,0 @@ -=================================== -Customizing LLVMC: Reference Manual -=================================== -.. - This file was automatically generated by rst2html. - Please do not edit directly! - The ReST source lives in the directory 'tools/llvmc/doc'. - -.. contents:: - -.. raw:: html - - <div class="doc_author"> - <p>Written by <a href="mailto:foldr@codedgers.com">Mikhail Glushenkov</a></p> - </div> - -Introduction -============ - -LLVMC is a generic compiler driver, designed to be customizable and -extensible. It plays the same role for LLVM as the ``gcc`` program -does for GCC - LLVMC's job is essentially to transform a set of input -files into a set of targets depending on configuration rules and user -options. What makes LLVMC different is that these transformation rules -are completely customizable - in fact, LLVMC knows nothing about the -specifics of transformation (even the command-line options are mostly -not hard-coded) and regards the transformation structure as an -abstract graph. The structure of this graph is completely determined -by plugins, which can be either statically or dynamically linked. This -makes it possible to easily adapt LLVMC for other purposes - for -example, as a build tool for game resources. - -Because LLVMC employs TableGen_ as its configuration language, you -need to be familiar with it to customize LLVMC. - -.. _TableGen: http://llvm.org/docs/TableGenFundamentals.html - - -Compiling with LLVMC -==================== - -LLVMC tries hard to be as compatible with ``gcc`` as possible, -although there are some small differences. Most of the time, however, -you shouldn't be able to notice them:: - - $ # This works as expected: - $ llvmc -O3 -Wall hello.cpp - $ ./a.out - hello - -One nice feature of LLVMC is that one doesn't have to distinguish between -different compilers for different languages (think ``g++`` vs. ``gcc``) - the -right toolchain is chosen automatically based on input language names (which -are, in turn, determined from file extensions). If you want to force files -ending with ".c" to compile as C++, use the ``-x`` option, just like you would -do it with ``gcc``:: - - $ # hello.c is really a C++ file - $ llvmc -x c++ hello.c - $ ./a.out - hello - -On the other hand, when using LLVMC as a linker to combine several C++ -object files you should provide the ``--linker`` option since it's -impossible for LLVMC to choose the right linker in that case:: - - $ llvmc -c hello.cpp - $ llvmc hello.o - [A lot of link-time errors skipped] - $ llvmc --linker=c++ hello.o - $ ./a.out - hello - -By default, LLVMC uses ``llvm-gcc`` to compile the source code. It is also -possible to choose the ``clang`` compiler with the ``-clang`` option. - - -Predefined options -================== - -LLVMC has some built-in options that can't be overridden in the -configuration libraries: - -* ``-o FILE`` - Output file name. - -* ``-x LANGUAGE`` - Specify the language of the following input files - until the next -x option. - -* ``-load PLUGIN_NAME`` - Load the specified plugin DLL. Example: - ``-load $LLVM_DIR/Release/lib/LLVMCSimple.so``. - -* ``-v`` - Enable verbose mode, i.e. print out all executed commands. - -* ``--save-temps`` - Write temporary files to the current directory and do not - delete them on exit. This option can also take an argument: the - ``--save-temps=obj`` switch will write files into the directory specified with - the ``-o`` option. The ``--save-temps=cwd`` and ``--save-temps`` switches are - both synonyms for the default behaviour. - -* ``--temp-dir DIRECTORY`` - Store temporary files in the given directory. This - directory is deleted on exit unless ``--save-temps`` is specified. If - ``--save-temps=obj`` is also specified, ``--temp-dir`` is given the - precedence. - -* ``--check-graph`` - Check the compilation for common errors like mismatched - output/input language names, multiple default edges and cycles. Because of - plugins, these checks can't be performed at compile-time. Exit with code zero - if no errors were found, and return the number of found errors - otherwise. Hidden option, useful for debugging LLVMC plugins. - -* ``--view-graph`` - Show a graphical representation of the compilation graph - and exit. Requires that you have ``dot`` and ``gv`` programs installed. Hidden - option, useful for debugging LLVMC plugins. - -* ``--write-graph`` - Write a ``compilation-graph.dot`` file in the current - directory with the compilation graph description in Graphviz format (identical - to the file used by the ``--view-graph`` option). The ``-o`` option can be - used to set the output file name. Hidden option, useful for debugging LLVMC - plugins. - -* ``--help``, ``--help-hidden``, ``--version`` - These options have - their standard meaning. - -Compiling LLVMC plugins -======================= - -It's easiest to start working on your own LLVMC plugin by copying the -skeleton project which lives under ``$LLVMC_DIR/plugins/Simple``:: - - $ cd $LLVMC_DIR/plugins - $ cp -r Simple MyPlugin - $ cd MyPlugin - $ ls - Makefile PluginMain.cpp Simple.td - -As you can see, our basic plugin consists of only two files (not -counting the build script). ``Simple.td`` contains TableGen -description of the compilation graph; its format is documented in the -following sections. ``PluginMain.cpp`` is just a helper file used to -compile the auto-generated C++ code produced from TableGen source. It -can also contain hook definitions (see `below`__). - -__ hooks_ - -The first thing that you should do is to change the ``LLVMC_PLUGIN`` -variable in the ``Makefile`` to avoid conflicts (since this variable -is used to name the resulting library):: - - LLVMC_PLUGIN=MyPlugin - -It is also a good idea to rename ``Simple.td`` to something less -generic:: - - $ mv Simple.td MyPlugin.td - -To build your plugin as a dynamic library, just ``cd`` to its source -directory and run ``make``. The resulting file will be called -``plugin_llvmc_$(LLVMC_PLUGIN).$(DLL_EXTENSION)`` (in our case, -``plugin_llvmc_MyPlugin.so``). This library can be then loaded in with the -``-load`` option. Example:: - - $ cd $LLVMC_DIR/plugins/Simple - $ make - $ llvmc -load $LLVM_DIR/Release/lib/plugin_llvmc_Simple.so - -Compiling standalone LLVMC-based drivers -======================================== - -By default, the ``llvmc`` executable consists of a driver core plus several -statically linked plugins (``Base`` and ``Clang`` at the moment). You can -produce a standalone LLVMC-based driver executable by linking the core with your -own plugins. The recommended way to do this is by starting with the provided -``Skeleton`` example (``$LLVMC_DIR/example/Skeleton``):: - - $ cd $LLVMC_DIR/example/ - $ cp -r Skeleton mydriver - $ cd mydriver - $ vim Makefile - [...] - $ make - -If you're compiling LLVM with different source and object directories, then you -must perform the following additional steps before running ``make``:: - - # LLVMC_SRC_DIR = $LLVM_SRC_DIR/tools/llvmc/ - # LLVMC_OBJ_DIR = $LLVM_OBJ_DIR/tools/llvmc/ - $ cp $LLVMC_SRC_DIR/example/mydriver/Makefile \ - $LLVMC_OBJ_DIR/example/mydriver/ - $ cd $LLVMC_OBJ_DIR/example/mydriver - $ make - -Another way to do the same thing is by using the following command:: - - $ cd $LLVMC_DIR - $ make LLVMC_BUILTIN_PLUGINS=MyPlugin LLVMC_BASED_DRIVER_NAME=mydriver - -This works with both srcdir == objdir and srcdir != objdir, but assumes that the -plugin source directory was placed under ``$LLVMC_DIR/plugins``. - -Sometimes, you will want a 'bare-bones' version of LLVMC that has no -built-in plugins. It can be compiled with the following command:: - - $ cd $LLVMC_DIR - $ make LLVMC_BUILTIN_PLUGINS="" - - -Customizing LLVMC: the compilation graph -======================================== - -Each TableGen configuration file should include the common -definitions:: - - include "llvm/CompilerDriver/Common.td" - -Internally, LLVMC stores information about possible source -transformations in form of a graph. Nodes in this graph represent -tools, and edges between two nodes represent a transformation path. A -special "root" node is used to mark entry points for the -transformations. LLVMC also assigns a weight to each edge (more on -this later) to choose between several alternative edges. - -The definition of the compilation graph (see file -``plugins/Base/Base.td`` for an example) is just a list of edges:: - - def CompilationGraph : CompilationGraph<[ - Edge<"root", "llvm_gcc_c">, - Edge<"root", "llvm_gcc_assembler">, - ... - - Edge<"llvm_gcc_c", "llc">, - Edge<"llvm_gcc_cpp", "llc">, - ... - - OptionalEdge<"llvm_gcc_c", "opt", (case (switch_on "opt"), - (inc_weight))>, - OptionalEdge<"llvm_gcc_cpp", "opt", (case (switch_on "opt"), - (inc_weight))>, - ... - - OptionalEdge<"llvm_gcc_assembler", "llvm_gcc_cpp_linker", - (case (input_languages_contain "c++"), (inc_weight), - (or (parameter_equals "linker", "g++"), - (parameter_equals "linker", "c++")), (inc_weight))>, - ... - - ]>; - -As you can see, the edges can be either default or optional, where -optional edges are differentiated by an additional ``case`` expression -used to calculate the weight of this edge. Notice also that we refer -to tools via their names (as strings). This makes it possible to add -edges to an existing compilation graph in plugins without having to -know about all tool definitions used in the graph. - -The default edges are assigned a weight of 1, and optional edges get a -weight of 0 + 2*N where N is the number of tests that evaluated to -true in the ``case`` expression. It is also possible to provide an -integer parameter to ``inc_weight`` and ``dec_weight`` - in this case, -the weight is increased (or decreased) by the provided value instead -of the default 2. It is also possible to change the default weight of -an optional edge by using the ``default`` clause of the ``case`` -construct. - -When passing an input file through the graph, LLVMC picks the edge -with the maximum weight. To avoid ambiguity, there should be only one -default edge between two nodes (with the exception of the root node, -which gets a special treatment - there you are allowed to specify one -default edge *per language*). - -When multiple plugins are loaded, their compilation graphs are merged -together. Since multiple edges that have the same end nodes are not -allowed (i.e. the graph is not a multigraph), an edge defined in -several plugins will be replaced by the definition from the plugin -that was loaded last. Plugin load order can be controlled by using the -plugin priority feature described above. - -To get a visual representation of the compilation graph (useful for -debugging), run ``llvmc --view-graph``. You will need ``dot`` and -``gsview`` installed for this to work properly. - -Describing options -================== - -Command-line options that the plugin supports are defined by using an -``OptionList``:: - - def Options : OptionList<[ - (switch_option "E", (help "Help string")), - (alias_option "quiet", "q") - ... - ]>; - -As you can see, the option list is just a list of DAGs, where each DAG -is an option description consisting of the option name and some -properties. A plugin can define more than one option list (they are -all merged together in the end), which can be handy if one wants to -separate option groups syntactically. - -* Possible option types: - - - ``switch_option`` - a simple boolean switch without arguments, for example - ``-O2`` or ``-time``. At most one occurrence is allowed by default. - - - ``parameter_option`` - option that takes one argument, for example - ``-std=c99``. It is also allowed to use spaces instead of the equality - sign: ``-std c99``. At most one occurrence is allowed. - - - ``parameter_list_option`` - same as the above, but more than one option - occurence is allowed. - - - ``prefix_option`` - same as the parameter_option, but the option name and - argument do not have to be separated. Example: ``-ofile``. This can be also - specified as ``-o file``; however, ``-o=file`` will be parsed incorrectly - (``=file`` will be interpreted as option value). At most one occurrence is - allowed. - - - ``prefix_list_option`` - same as the above, but more than one occurence of - the option is allowed; example: ``-lm -lpthread``. - - - ``alias_option`` - a special option type for creating aliases. Unlike other - option types, aliases are not allowed to have any properties besides the - aliased option name. Usage example: ``(alias_option "preprocess", "E")`` - - - ``switch_list_option`` - like ``switch_option`` with the ``zero_or_more`` - property, but remembers how many times the switch was turned on. Useful - mostly for forwarding. Example: when ``-foo`` is a switch option (with the - ``zero_or_more`` property), the command ``driver -foo -foo`` is forwarded - as ``some-tool -foo``, but when ``-foo`` is a switch list, the same command - is forwarded as ``some-tool -foo -foo``. - - -* Possible option properties: - - - ``help`` - help string associated with this option. Used for ``--help`` - output. - - - ``required`` - this option must be specified exactly once (or, in case of - the list options without the ``multi_val`` property, at least - once). Incompatible with ``optional`` and ``one_or_more``. - - - ``optional`` - the option can be specified either zero times or exactly - once. The default for switch options. Useful only for list options in - conjunction with ``multi_val``. Incompatible with ``required``, - ``zero_or_more`` and ``one_or_more``. - - - ``one_or_more`` - the option must be specified at least once. Can be useful - to allow switch options be both obligatory and be specified multiple - times. For list options is useful only in conjunction with ``multi_val``; - for ordinary it is synonymous with ``required``. Incompatible with - ``required``, ``optional`` and ``zero_or_more``. - - - ``zero_or_more`` - the option can be specified zero or more times. Useful - to allow a single switch option to be specified more than - once. Incompatible with ``required``, ``optional`` and ``one_or_more``. - - - ``hidden`` - the description of this option will not appear in - the ``--help`` output (but will appear in the ``--help-hidden`` - output). - - - ``really_hidden`` - the option will not be mentioned in any help - output. - - - ``comma_separated`` - Indicates that any commas specified for an option's - value should be used to split the value up into multiple values for the - option. This property is valid only for list options. In conjunction with - ``forward_value`` can be used to implement option forwarding in style of - gcc's ``-Wa,``. - - - ``multi_val n`` - this option takes *n* arguments (can be useful in some - special cases). Usage example: ``(parameter_list_option "foo", (multi_val - 3))``; the command-line syntax is '-foo a b c'. Only list options can have - this attribute; you can, however, use the ``one_or_more``, ``optional`` - and ``required`` properties. - - - ``init`` - this option has a default value, either a string (if it is a - parameter), or a boolean (if it is a switch; as in C++, boolean constants - are called ``true`` and ``false``). List options can't have ``init`` - attribute. - Usage examples: ``(switch_option "foo", (init true))``; ``(prefix_option - "bar", (init "baz"))``. - - - ``extern`` - this option is defined in some other plugin, see `below`__. - - __ extern_ - -.. _extern: - -External options ----------------- - -Sometimes, when linking several plugins together, one plugin needs to -access options defined in some other plugin. Because of the way -options are implemented, such options must be marked as -``extern``. This is what the ``extern`` option property is -for. Example:: - - ... - (switch_option "E", (extern)) - ... - -If an external option has additional attributes besides 'extern', they are -ignored. See also the section on plugin `priorities`__. - -__ priorities_ - -.. _case: - -Conditional evaluation -====================== - -The 'case' construct is the main means by which programmability is -achieved in LLVMC. It can be used to calculate edge weights, program -actions and modify the shell commands to be executed. The 'case' -expression is designed after the similarly-named construct in -functional languages and takes the form ``(case (test_1), statement_1, -(test_2), statement_2, ... (test_N), statement_N)``. The statements -are evaluated only if the corresponding tests evaluate to true. - -Examples:: - - // Edge weight calculation - - // Increases edge weight by 5 if "-A" is provided on the - // command-line, and by 5 more if "-B" is also provided. - (case - (switch_on "A"), (inc_weight 5), - (switch_on "B"), (inc_weight 5)) - - - // Tool command line specification - - // Evaluates to "cmdline1" if the option "-A" is provided on the - // command line; to "cmdline2" if "-B" is provided; - // otherwise to "cmdline3". - - (case - (switch_on "A"), "cmdline1", - (switch_on "B"), "cmdline2", - (default), "cmdline3") - -Note the slight difference in 'case' expression handling in contexts -of edge weights and command line specification - in the second example -the value of the ``"B"`` switch is never checked when switch ``"A"`` is -enabled, and the whole expression always evaluates to ``"cmdline1"`` in -that case. - -Case expressions can also be nested, i.e. the following is legal:: - - (case (switch_on "E"), (case (switch_on "o"), ..., (default), ...) - (default), ...) - -You should, however, try to avoid doing that because it hurts -readability. It is usually better to split tool descriptions and/or -use TableGen inheritance instead. - -* Possible tests are: - - - ``switch_on`` - Returns true if a given command-line switch is provided by - the user. Can be given a list as argument, in that case ``(switch_on ["foo", - "bar", "baz"])`` is equivalent to ``(and (switch_on "foo"), (switch_on - "bar"), (switch_on "baz"))``. - Example: ``(switch_on "opt")``. - - - ``any_switch_on`` - Given a list of switch options, returns true if any of - the switches is turned on. - Example: ``(any_switch_on ["foo", "bar", "baz"])`` is equivalent to ``(or - (switch_on "foo"), (switch_on "bar"), (switch_on "baz"))``. - - - ``parameter_equals`` - Returns true if a command-line parameter equals - a given value. - Example: ``(parameter_equals "W", "all")``. - - - ``element_in_list`` - Returns true if a command-line parameter - list contains a given value. - Example: ``(element_in_list "l", "pthread")``. - - - ``input_languages_contain`` - Returns true if a given language - belongs to the current input language set. - Example: ``(input_languages_contain "c++")``. - - - ``in_language`` - Evaluates to true if the input file language is equal to - the argument. At the moment works only with ``cmd_line`` and ``actions`` (on - non-join nodes). - Example: ``(in_language "c++")``. - - - ``not_empty`` - Returns true if a given option (which should be either a - parameter or a parameter list) is set by the user. Like ``switch_on``, can - be also given a list as argument. - Example: ``(not_empty "o")``. - - - ``any_not_empty`` - Returns true if ``not_empty`` returns true for any of - the options in the list. - Example: ``(any_not_empty ["foo", "bar", "baz"])`` is equivalent to ``(or - (not_empty "foo"), (not_empty "bar"), (not_empty "baz"))``. - - - ``empty`` - The opposite of ``not_empty``. Equivalent to ``(not (not_empty - X))``. Provided for convenience. Can be given a list as argument. - - - ``any_not_empty`` - Returns true if ``not_empty`` returns true for any of - the options in the list. - Example: ``(any_empty ["foo", "bar", "baz"])`` is equivalent to ``(not (and - (not_empty "foo"), (not_empty "bar"), (not_empty "baz")))``. - - - ``single_input_file`` - Returns true if there was only one input file - provided on the command-line. Used without arguments: - ``(single_input_file)``. - - - ``multiple_input_files`` - Equivalent to ``(not (single_input_file))`` (the - case of zero input files is considered an error). - - - ``default`` - Always evaluates to true. Should always be the last - test in the ``case`` expression. - - - ``and`` - A standard binary logical combinator that returns true iff all of - its arguments return true. Used like this: ``(and (test1), (test2), - ... (testN))``. Nesting of ``and`` and ``or`` is allowed, but not - encouraged. - - - ``or`` - A binary logical combinator that returns true iff any of its - arguments returns true. Example: ``(or (test1), (test2), ... (testN))``. - - - ``not`` - Standard unary logical combinator that negates its - argument. Example: ``(not (or (test1), (test2), ... (testN)))``. - - - -Writing a tool description -========================== - -As was said earlier, nodes in the compilation graph represent tools, -which are described separately. A tool definition looks like this -(taken from the ``include/llvm/CompilerDriver/Tools.td`` file):: - - def llvm_gcc_cpp : Tool<[ - (in_language "c++"), - (out_language "llvm-assembler"), - (output_suffix "bc"), - (cmd_line "llvm-g++ -c $INFILE -o $OUTFILE -emit-llvm"), - (sink) - ]>; - -This defines a new tool called ``llvm_gcc_cpp``, which is an alias for -``llvm-g++``. As you can see, a tool definition is just a list of -properties; most of them should be self-explanatory. The ``sink`` -property means that this tool should be passed all command-line -options that aren't mentioned in the option list. - -The complete list of all currently implemented tool properties follows. - -* Possible tool properties: - - - ``in_language`` - input language name. Can be either a string or a - list, in case the tool supports multiple input languages. - - - ``out_language`` - output language name. Multiple output languages are not - allowed. - - - ``output_suffix`` - output file suffix. Can also be changed - dynamically, see documentation on actions. - - - ``cmd_line`` - the actual command used to run the tool. You can - use ``$INFILE`` and ``$OUTFILE`` variables, output redirection - with ``>``, hook invocations (``$CALL``), environment variables - (via ``$ENV``) and the ``case`` construct. - - - ``join`` - this tool is a "join node" in the graph, i.e. it gets a - list of input files and joins them together. Used for linkers. - - - ``sink`` - all command-line options that are not handled by other - tools are passed to this tool. - - - ``actions`` - A single big ``case`` expression that specifies how - this tool reacts on command-line options (described in more detail - `below`__). - -__ actions_ - -.. _actions: - -Actions -------- - -A tool often needs to react to command-line options, and this is -precisely what the ``actions`` property is for. The next example -illustrates this feature:: - - def llvm_gcc_linker : Tool<[ - (in_language "object-code"), - (out_language "executable"), - (output_suffix "out"), - (cmd_line "llvm-gcc $INFILE -o $OUTFILE"), - (join), - (actions (case (not_empty "L"), (forward "L"), - (not_empty "l"), (forward "l"), - (not_empty "dummy"), - [(append_cmd "-dummy1"), (append_cmd "-dummy2")]) - ]>; - -The ``actions`` tool property is implemented on top of the omnipresent -``case`` expression. It associates one or more different *actions* -with given conditions - in the example, the actions are ``forward``, -which forwards a given option unchanged, and ``append_cmd``, which -appends a given string to the tool execution command. Multiple actions -can be associated with a single condition by using a list of actions -(used in the example to append some dummy options). The same ``case`` -construct can also be used in the ``cmd_line`` property to modify the -tool command line. - -The "join" property used in the example means that this tool behaves -like a linker. - -The list of all possible actions follows. - -* Possible actions: - - - ``append_cmd`` - Append a string to the tool invocation command. - Example: ``(case (switch_on "pthread"), (append_cmd "-lpthread"))``. - - - ``error`` - Exit with error. - Example: ``(error "Mixing -c and -S is not allowed!")``. - - - ``warning`` - Print a warning. - Example: ``(warning "Specifying both -O1 and -O2 is meaningless!")``. - - - ``forward`` - Forward the option unchanged. - Example: ``(forward "Wall")``. - - - ``forward_as`` - Change the option's name, but forward the argument - unchanged. - Example: ``(forward_as "O0", "--disable-optimization")``. - - - ``forward_value`` - Forward only option's value. Cannot be used with switch - options (since they don't have values), but works fine with lists. - Example: ``(forward_value "Wa,")``. - - - ``forward_transformed_value`` - As above, but applies a hook to the - option's value before forwarding (see `below`__). When - ``forward_transformed_value`` is applied to a list - option, the hook must have signature - ``std::string hooks::HookName (const std::vector<std::string>&)``. - Example: ``(forward_transformed_value "m", "ConvertToMAttr")``. - - __ hooks_ - - - ``output_suffix`` - Modify the output suffix of this tool. - Example: ``(output_suffix "i")``. - - - ``stop_compilation`` - Stop compilation after this tool processes its - input. Used without arguments. - Example: ``(stop_compilation)``. - - -Language map -============ - -If you are adding support for a new language to LLVMC, you'll need to -modify the language map, which defines mappings from file extensions -to language names. It is used to choose the proper toolchain(s) for a -given input file set. Language map definition looks like this:: - - def LanguageMap : LanguageMap< - [LangToSuffixes<"c++", ["cc", "cp", "cxx", "cpp", "CPP", "c++", "C"]>, - LangToSuffixes<"c", ["c"]>, - ... - ]>; - -For example, without those definitions the following command wouldn't work:: - - $ llvmc hello.cpp - llvmc: Unknown suffix: cpp - -The language map entries are needed only for the tools that are linked from the -root node. Since a tool can't have multiple output languages, for inner nodes of -the graph the input and output languages should match. This is enforced at -compile-time. - -Option preprocessor -=================== - -It is sometimes useful to run error-checking code before processing the -compilation graph. For example, if optimization options "-O1" and "-O2" are -implemented as switches, we might want to output a warning if the user invokes -the driver with both of these options enabled. - -The ``OptionPreprocessor`` feature is reserved specially for these -occasions. Example (adapted from the built-in Base plugin):: - - - def Preprocess : OptionPreprocessor< - (case (not (any_switch_on ["O0", "O1", "O2", "O3"])), - (set_option "O2"), - (and (switch_on "O3"), (any_switch_on ["O0", "O1", "O2"])), - (unset_option ["O0", "O1", "O2"]), - (and (switch_on "O2"), (any_switch_on ["O0", "O1"])), - (unset_option ["O0", "O1"]), - (and (switch_on "O1"), (switch_on "O0")), - (unset_option "O0")) - >; - -Here, ``OptionPreprocessor`` is used to unset all spurious ``-O`` options so -that they are not forwarded to the compiler. If no optimization options are -specified, ``-O2`` is enabled. - -``OptionPreprocessor`` is basically a single big ``case`` expression, which is -evaluated only once right after the plugin is loaded. The only allowed actions -in ``OptionPreprocessor`` are ``error``, ``warning``, and two special actions: -``unset_option`` and ``set_option``. As their names suggest, they can be used to -set or unset a given option. To set an option with ``set_option``, use the -two-argument form: ``(set_option "parameter", VALUE)``. Here, ``VALUE`` can be -either a string, a string list, or a boolean constant. - -For convenience, ``set_option`` and ``unset_option`` also work on lists. That -is, instead of ``[(unset_option "A"), (unset_option "B")]`` you can use -``(unset_option ["A", "B"])``. Obviously, ``(set_option ["A", "B"])`` is valid -only if both ``A`` and ``B`` are switches. - - -More advanced topics -==================== - -.. _hooks: - -Hooks and environment variables -------------------------------- - -Normally, LLVMC executes programs from the system ``PATH``. Sometimes, -this is not sufficient: for example, we may want to specify tool paths -or names in the configuration file. This can be easily achieved via -the hooks mechanism. To write your own hooks, just add their -definitions to the ``PluginMain.cpp`` or drop a ``.cpp`` file into the -your plugin directory. Hooks should live in the ``hooks`` namespace -and have the signature ``std::string hooks::MyHookName ([const char* -Arg0 [ const char* Arg2 [, ...]]])``. They can be used from the -``cmd_line`` tool property:: - - (cmd_line "$CALL(MyHook)/path/to/file -o $CALL(AnotherHook)") - -To pass arguments to hooks, use the following syntax:: - - (cmd_line "$CALL(MyHook, 'Arg1', 'Arg2', 'Arg # 3')/path/to/file -o1 -o2") - -It is also possible to use environment variables in the same manner:: - - (cmd_line "$ENV(VAR1)/path/to/file -o $ENV(VAR2)") - -To change the command line string based on user-provided options use -the ``case`` expression (documented `above`__):: - - (cmd_line - (case - (switch_on "E"), - "llvm-g++ -E -x c $INFILE -o $OUTFILE", - (default), - "llvm-g++ -c -x c $INFILE -o $OUTFILE -emit-llvm")) - -__ case_ - -.. _priorities: - -How plugins are loaded ----------------------- - -It is possible for LLVMC plugins to depend on each other. For example, -one can create edges between nodes defined in some other plugin. To -make this work, however, that plugin should be loaded first. To -achieve this, the concept of plugin priority was introduced. By -default, every plugin has priority zero; to specify the priority -explicitly, put the following line in your plugin's TableGen file:: - - def Priority : PluginPriority<$PRIORITY_VALUE>; - # Where PRIORITY_VALUE is some integer > 0 - -Plugins are loaded in order of their (increasing) priority, starting -with 0. Therefore, the plugin with the highest priority value will be -loaded last. - -Debugging ---------- - -When writing LLVMC plugins, it can be useful to get a visual view of -the resulting compilation graph. This can be achieved via the command -line option ``--view-graph``. This command assumes that Graphviz_ and -Ghostview_ are installed. There is also a ``--write-graph`` option that -creates a Graphviz source file (``compilation-graph.dot``) in the -current directory. - -Another useful ``llvmc`` option is ``--check-graph``. It checks the -compilation graph for common errors like mismatched output/input -language names, multiple default edges and cycles. These checks can't -be performed at compile-time because the plugins can load code -dynamically. When invoked with ``--check-graph``, ``llvmc`` doesn't -perform any compilation tasks and returns the number of encountered -errors as its status code. - -.. _Graphviz: http://www.graphviz.org/ -.. _Ghostview: http://pages.cs.wisc.edu/~ghost/ - -Conditioning on the executable name ------------------------------------ - -For now, the executable name (the value passed to the driver in ``argv[0]``) is -accessible only in the C++ code (i.e. hooks). Use the following code:: - - namespace llvmc { - extern const char* ProgramName; - } - - namespace hooks { - - std::string MyHook() { - //... - if (strcmp(ProgramName, "mydriver") == 0) { - //... - - } - - } // end namespace hooks - -In general, you're encouraged not to make the behaviour dependent on the -executable file name, and use command-line switches instead. See for example how -the ``Base`` plugin behaves when it needs to choose the correct linker options -(think ``g++`` vs. ``gcc``). - -.. raw:: html - - <hr /> - <address> - <a href="http://jigsaw.w3.org/css-validator/check/referer"> - <img src="http://jigsaw.w3.org/css-validator/images/vcss-blue" - alt="Valid CSS" /></a> - <a href="http://validator.w3.org/check?uri=referer"> - <img src="http://www.w3.org/Icons/valid-xhtml10-blue" - alt="Valid XHTML 1.0 Transitional"/></a> - - <a href="mailto:foldr@codedgers.com">Mikhail Glushenkov</a><br /> - <a href="http://llvm.org">LLVM Compiler Infrastructure</a><br /> - - Last modified: $Date: 2008-12-11 11:34:48 -0600 (Thu, 11 Dec 2008) $ - </address> diff --git a/contrib/llvm/tools/llvmc/doc/LLVMC-Tutorial.rst b/contrib/llvm/tools/llvmc/doc/LLVMC-Tutorial.rst deleted file mode 100644 index e7e8f08..0000000 --- a/contrib/llvm/tools/llvmc/doc/LLVMC-Tutorial.rst +++ /dev/null @@ -1,129 +0,0 @@ -====================== -Tutorial - Using LLVMC -====================== -.. - This file was automatically generated by rst2html. - Please do not edit directly! - The ReST source lives in the directory 'tools/llvmc/doc'. - -.. contents:: - -.. raw:: html - - <div class="doc_author"> - <p>Written by <a href="mailto:foldr@codedgers.com">Mikhail Glushenkov</a></p> - </div> - -Introduction -============ - -LLVMC is a generic compiler driver, which plays the same role for LLVM -as the ``gcc`` program does for GCC - the difference being that LLVMC -is designed to be more adaptable and easier to customize. Most of -LLVMC functionality is implemented via plugins, which can be loaded -dynamically or compiled in. This tutorial describes the basic usage -and configuration of LLVMC. - - -Compiling with LLVMC -==================== - -In general, LLVMC tries to be command-line compatible with ``gcc`` as -much as possible, so most of the familiar options work:: - - $ llvmc -O3 -Wall hello.cpp - $ ./a.out - hello - -This will invoke ``llvm-g++`` under the hood (you can see which -commands are executed by using the ``-v`` option). For further help on -command-line LLVMC usage, refer to the ``llvmc --help`` output. - - -Using LLVMC to generate toolchain drivers -========================================= - -LLVMC plugins are written mostly using TableGen_, so you need to -be familiar with it to get anything done. - -.. _TableGen: http://llvm.org/docs/TableGenFundamentals.html - -Start by compiling ``example/Simple``, which is a primitive wrapper for -``gcc``:: - - $ cd $LLVM_DIR/tools/llvmc - $ cp -r example/Simple plugins/Simple - - # NB: A less verbose way to compile standalone LLVMC-based drivers is - # described in the reference manual. - - $ make LLVMC_BASED_DRIVER_NAME=mygcc LLVMC_BUILTIN_PLUGINS=Simple - $ cat > hello.c - [...] - $ mygcc hello.c - $ ./hello.out - Hello - -Here we link our plugin with the LLVMC core statically to form an executable -file called ``mygcc``. It is also possible to build our plugin as a dynamic -library to be loaded by the ``llvmc`` executable (or any other LLVMC-based -standalone driver); this is described in the reference manual. - -Contents of the file ``Simple.td`` look like this:: - - // Include common definitions - include "llvm/CompilerDriver/Common.td" - - // Tool descriptions - def gcc : Tool< - [(in_language "c"), - (out_language "executable"), - (output_suffix "out"), - (cmd_line "gcc $INFILE -o $OUTFILE"), - (sink) - ]>; - - // Language map - def LanguageMap : LanguageMap<[LangToSuffixes<"c", ["c"]>]>; - - // Compilation graph - def CompilationGraph : CompilationGraph<[Edge<"root", "gcc">]>; - -As you can see, this file consists of three parts: tool descriptions, -language map, and the compilation graph definition. - -At the heart of LLVMC is the idea of a compilation graph: vertices in -this graph are tools, and edges represent a transformation path -between two tools (for example, assembly source produced by the -compiler can be transformed into executable code by an assembler). The -compilation graph is basically a list of edges; a special node named -``root`` is used to mark graph entry points. - -Tool descriptions are represented as property lists: most properties -in the example above should be self-explanatory; the ``sink`` property -means that all options lacking an explicit description should be -forwarded to this tool. - -The ``LanguageMap`` associates a language name with a list of suffixes -and is used for deciding which toolchain corresponds to a given input -file. - -To learn more about LLVMC customization, refer to the reference -manual and plugin source code in the ``plugins`` directory. - -.. raw:: html - - <hr /> - <address> - <a href="http://jigsaw.w3.org/css-validator/check/referer"> - <img src="http://jigsaw.w3.org/css-validator/images/vcss-blue" - alt="Valid CSS" /></a> - <a href="http://validator.w3.org/check?uri=referer"> - <img src="http://www.w3.org/Icons/valid-xhtml10-blue" - alt="Valid XHTML 1.0 Transitional"/></a> - - <a href="mailto:foldr@codedgers.com">Mikhail Glushenkov</a><br /> - <a href="http://llvm.org">LLVM Compiler Infrastructure</a><br /> - - Last modified: $Date: 2008-12-11 11:34:48 -0600 (Thu, 11 Dec 2008) $ - </address> diff --git a/contrib/llvm/tools/llvmc/doc/Makefile b/contrib/llvm/tools/llvmc/doc/Makefile deleted file mode 100644 index ef98767..0000000 --- a/contrib/llvm/tools/llvmc/doc/Makefile +++ /dev/null @@ -1,33 +0,0 @@ -##===- tools/llvmc/doc/Makefile ----------------------------*- Makefile -*-===## -# -# The LLVM Compiler Infrastructure -# -# This file is distributed under the University of Illinois Open Source -# License. See LICENSE.TXT for details. -# -##===----------------------------------------------------------------------===## - -LEVEL=../../.. - -ifneq (,$(strip $(wildcard $(LEVEL)/Makefile.config))) -include $(LEVEL)/Makefile.config -else -CP=cp -RM=rm -endif - -DOC_DIR=../../../docs -RST2HTML=rst2html --stylesheet=llvm.css --link-stylesheet - -all : LLVMC-Reference.html LLVMC-Tutorial.html - $(CP) LLVMC-Reference.html $(DOC_DIR)/CompilerDriver.html - $(CP) LLVMC-Tutorial.html $(DOC_DIR)/CompilerDriverTutorial.html - -LLVMC-Tutorial.html : LLVMC-Tutorial.rst - $(RST2HTML) $< $@ - -LLVMC-Reference.html : LLVMC-Reference.rst - $(RST2HTML) $< $@ - -clean : - $(RM) LLVMC-Tutorial.html LLVMC-Reference.html diff --git a/contrib/llvm/tools/llvmc/doc/img/lines.gif b/contrib/llvm/tools/llvmc/doc/img/lines.gif Binary files differdeleted file mode 100644 index 88f491e..0000000 --- a/contrib/llvm/tools/llvmc/doc/img/lines.gif +++ /dev/null |
