diff options
| -rw-r--r-- | cleave/cleave.cc | 244 | ||||
| -rw-r--r-- | cleave/makefile | 7 | ||||
| -rw-r--r-- | makefile | 43 |
3 files changed, 287 insertions, 7 deletions
diff --git a/cleave/cleave.cc b/cleave/cleave.cc new file mode 100644 index 00000000..ee83bbf2 --- /dev/null +++ b/cleave/cleave.cc @@ -0,0 +1,244 @@ +// Read a single-file C++ program having a very specific structure, and split +// it up into multiple separate compilation units to reduce the work needed to +// rebuild after a small change. Write each compilation unit only if it has +// changed from what was on disk before. +// +// This tool is tightly coupled with the build system for this project. The +// makefile already auto-generates various things; we only do here what +// standard unix tools can't easily do. +// +// Usage: +// cleave [input C++ file] [existing output directory] +// +// The input C++ file has the following structure: +// [#includes] +// [type definitions] +// // Globals +// [global variable definitions] +// // End Globals +// [function definitions] +// +// Afterwards, the output directory contains: +// header -- everything before the '// Globals' delimiter +// global_definitions_list -- everything between '// Globals' and '// End Globals' delimiters +// [.cc files partitioning function definitions] +// +// Each output function definition file contains: +// #include "header" +// #include "global_declarations_list" +// [function definitions] +// +// We'll chunk the files at boundaries where we encounter a '#line ' directive +// between functions. +// +// One exception: the first file emitted #includes "global_definitions_list" instead +// of "global_declarations_list" + +// Tune this parameter to balance time for initial vs incremental build. +// +// Larger numbers -> larger/fewer compilation units -> faster initial build +// Smaller numbers -> smaller compilation units -> faster incremental build +int Compilation_unit_size = 200; + +#include<assert.h> +#include<cstdlib> +#include<cstring> + +#include<vector> +using std::vector; +#include<list> +using std::list; +#include<utility> +using std::pair; + +#include<string> +using std::string; + +#include<iostream> +using std::istream; +using std::ostream; +using std::cin; +using std::cout; +using std::cerr; + +#include<sstream> +using std::istringstream; +using std::ostringstream; + +#include<fstream> +using std::ifstream; +using std::ofstream; + +#include <locale> +using std::isspace; // unicode-aware + +string trim(const string& s) { + string::const_iterator first = s.begin(); + while (first != s.end() && isspace(*first)) + ++first; + if (first == s.end()) return ""; + + string::const_iterator last = --s.end(); + while (last != s.begin() && isspace(*last)) + --last; + ++last; + return string(first, last); +} + +bool starts_with(const string& s, const string& pat) { + return s.substr(0, pat.size()) == pat; +} + +bool has_data(istream& in) { + return in && !in.eof(); +} + +void slurp(const string/*copy*/ filename, vector<string>& lines) { + lines.clear(); + ifstream in(filename.c_str()); + while (has_data(in)) { + string curr_line; + getline(in, curr_line); + lines.push_back(curr_line); + } +} + +size_t slurp_some_functions(const vector<string>& in, size_t start, vector<string>& out, bool first) { + out.clear(); + if (start >= in.size()) return start; + out.push_back("#include \"header\""); + if (first) + out.push_back("#include \"global_definitions_list\""); + else + out.push_back("#include \"global_declarations_list\""); + out.push_back(""); + size_t curr = start; + for (int i = 0; i < Compilation_unit_size; ++i) { + while (curr < in.size()) { + // read functions -- lines until unindented '}' + while (curr < in.size()) { + const string& line = in.at(curr); +//? cerr << curr << ": adding to function: " << line << '\n'; + out.push_back(line); ++curr; + if (!line.empty() && line.at(0) == '}') break; + } + // now look for a '#line' directive before the next non-comment non-empty + // line + while (curr < in.size()) { + const string& line = in.at(curr); + if (starts_with(line, "#line ")) goto try_return; + out.push_back(line); ++curr; + if (trim(line).empty()) continue; + if (starts_with(trim(line), "//")) continue; + break; + } + } + try_return:; + } + + // Idea: Increase the number of functions to include in the next call to + // slurp_some_functions. + // Early functions are more likely to be larger because later layers added + // to them. +//? Compilation_unit_size *= 1.5; + return curr; +} + +// compare contents of a file with a list of lines, ignoring #line directives +// on both sides +bool no_change(const vector<string>& lines, const string& output_filename) { + vector<string> old_lines; + slurp(output_filename, old_lines); + size_t l=0, o=0; + while (true) { + while (l < lines.size() && + (lines.at(l).empty() || starts_with(lines.at(l), "#line "))) { + ++l; + } + while (o < old_lines.size() && + (old_lines.at(o).empty() || starts_with(old_lines.at(o), "#line "))) { + ++o; + } + if (l >= lines.size() && o >= old_lines.size()) return true; // no change + if (l >= lines.size() || o >= old_lines.size()) return false; // contents changed +//? cerr << "comparing\n"; +//? cerr << o << ": " << old_lines.at(o) << '\n'; +//? cerr << l << ": " << lines.at(l) << '\n'; + if (lines.at(l) != old_lines.at(o)) return false; // contents changed + ++l; ++o; + } + assert(false); +} + +string next_output_filename(const string& output_directory) { + static int file_count = 0; + ostringstream out; + out << output_directory << "/mu_" << file_count << ".cc"; + file_count++; + return out.str(); +} + +void emit_file(const vector<string>& lines, const string& output_filename) { + if (no_change(lines, output_filename)) return; + cerr << " updating " << output_filename << '\n'; + ofstream out(output_filename.c_str()); + for (size_t i = 0; i < lines.size(); ++i) + out << lines.at(i) << '\n'; +} + +void emit_compilation_unit(const vector<string>& lines, const string& output_directory) { + string output_filename = next_output_filename(output_directory); + emit_file(lines, output_filename); +} + +int main(int argc, const char* argv[]) { + if (argc != 3) { + cerr << "usage: cleave [input .cc file] [output directory]\n"; + exit(0); + } + + vector<string> lines; + + // read input + slurp(argv[1], lines); + + string output_directory = argv[2]; + + // write header until but excluding '// Global' delimiter + size_t line_num = 0; + { + vector<string> out; + while (line_num < lines.size()) { + const string& line = lines.at(line_num); + if (trim(line) == "// Globals") break; // todo: #line directive for delimiters + out.push_back(line); + ++line_num; + } + emit_file(out, output_directory+"/header"); + } + + // write global_definitions_list (including delimiters) + { + vector<string> out; + while (line_num < lines.size()) { + const string& line = lines.at(line_num); + out.push_back(line); + ++line_num; + if (trim(line) == "// End Globals") break; + } + emit_file(out, output_directory+"/global_definitions_list"); + } + + // segment functions + // first one is special + if (line_num < lines.size()) { + vector<string> function; + line_num = slurp_some_functions(lines, line_num, function, true); + emit_compilation_unit(function, output_directory); + } + while (line_num < lines.size()) { + vector<string> function; + line_num = slurp_some_functions(lines, line_num, function, false); + emit_compilation_unit(function, output_directory); + } +} diff --git a/cleave/makefile b/cleave/makefile new file mode 100644 index 00000000..33665b5c --- /dev/null +++ b/cleave/makefile @@ -0,0 +1,7 @@ +cleave: cleave.cc makefile + c++ -O3 -Wall -Wextra -fno-strict-aliasing cleave.cc -o cleave + +.PHONY: clean + +clean: + -rm cleave diff --git a/makefile b/makefile index a4c97916..3938cbb2 100644 --- a/makefile +++ b/makefile @@ -1,27 +1,51 @@ +# [0-9]*.cc -> mu.cc -> .build/*.cc -> .build/*.o -> .build/mu_bin +# (layers) | | | | +# tangle cleave $CXX $CXX +# +# [0-9]*.mu -> core.mu + all: mu_bin core.mu CXX ?= c++ CXXFLAGS ?= -g -O3 -# reduce memory usage for small servers -CXXFLAGS := ${CXXFLAGS} --param ggc-min-expand=1 --param ggc-min-heapsize=32768 +CXXFLAGS := ${CXXFLAGS} -Wall -Wextra -ftrapv -fno-strict-aliasing + +core.mu: [0-9]*.mu mu.cc makefile + cat $$(./enumerate/enumerate --until zzz |grep '.mu$$') > core.mu + +mu_bin: mu.cc makefile function_list test_list cleave/cleave + @mkdir -p .build + @cp function_list test_list .build + @mkdir -p .build/termbox + @cp termbox/termbox.h .build/termbox + ./cleave/cleave mu.cc .build + @# recursive (potentially parallel) make to pick up BUILD_SRC after cleave + @make .build/mu_bin + cp .build/mu_bin . + +BUILD_SRC=$(wildcard .build/*.cc) +.build/mu_bin: $(BUILD_SRC:.cc=.o) termbox/libtermbox.a + ${CXX} .build/*.o termbox/libtermbox.a -o .build/mu_bin -mu_bin: makefile mu.cc termbox/libtermbox.a function_list test_list - ${CXX} ${CXXFLAGS} -Wall -Wextra -ftrapv -fno-strict-aliasing mu.cc termbox/libtermbox.a -o mu_bin +.build/%.o: .build/%.cc .build/header .build/global_declarations_list + @# explicitly state default rule since we added dependencies + ${CXX} ${CXXFLAGS} -c $< -o $@ # To see what the program looks like after all layers have been applied, read # mu.cc mu.cc: [0-9]*.cc enumerate/enumerate tangle/tangle ./tangle/tangle $$(./enumerate/enumerate --until zzz |grep -v '.mu$$') > mu.cc -core.mu: [0-9]*.mu mu.cc - cat $$(./enumerate/enumerate --until zzz |grep '.mu$$') > core.mu - enumerate/enumerate: cd enumerate && make tangle/tangle: cd tangle && make && ./tangle test +cleave/cleave: cleave/cleave.cc + cd cleave && make + rm -rf .build + termbox/libtermbox.a: termbox/*.c termbox/*.h termbox/*.inl cd termbox && make @@ -43,12 +67,17 @@ test_list: mu.cc @grep -h "^\s*void test_" mu.cc |perl -pwe 's/^\s*void (.*)\(\) \{.*/$$1,/' > test_list @grep -h "^\s*TEST(" mu.cc |perl -pwe 's/^\s*TEST\((.*)\)$$/test_$$1,/' >> test_list +.build/global_declarations_list: .build/global_definitions_list + grep ';' .build/global_definitions_list |perl -pwe 's/[=(].*/;/' |perl -pwe 's/^[^\/# ]/extern $$&/' |perl -pwe 's/^extern extern /extern /' > .build/global_declarations_list + .PHONY: all clean clena clena: clean clean: cd enumerate && make clean cd tangle && make clean + cd cleave && make clean cd termbox && make clean -rm mu.cc core.mu mu_bin *_list -rm -rf mu_bin.* + -rm -rf .build |