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Diffstat (limited to 'README')
| -rw-r--r-- | README | 47 |
1 files changed, 39 insertions, 8 deletions
@@ -5,22 +5,20 @@ Features: -------- - SMALL! You can compile and execute C code everywhere, for example on - rescue disks. + rescue disks (25KB for x86 executable). - FAST! tcc generates optimized x86 code. No byte code overhead. - UNLIMITED! Any C dynamic library can be used directly. TCC is - heading torwards full ANSI C compliance. TCC can of course compile + heading torward full ANSI C compliance. TCC can of course compile itself. - Compile and execute C source directly. No linking or assembly necessary. Full C preprocessor included. - C script supported : just add '#!/usr/local/bin/tcc' at the first - line of your C source, and execute it directly from the command line ! - -- For adventurers, tcc is conceived to be able to generate code for - other targets. + line of your C source, and execute it directly from the command + line. Documentation: ------------- @@ -37,7 +35,7 @@ Type 'make install' to compile and install tcc in /usr/local and We assume here that you know ANSI C. Look at the example ex1.c to know what the programs look like. -The main limitations of tcc are that you cannot use floats. +The main limitation of tcc is that you cannot use floats. The include file <tcclib.h> can be used if you want a small basic libc include support (especially useful for floppy disks). Of course, you @@ -117,6 +115,39 @@ Supported C extensions: - 'inline' keyword is ignored. +Technical Description: +--------------------- + +This is not my first C compiler (see my 'fbcc' compiler) but it +contains the first C preprocessor I wrote. The project started as a +joke to make the smallest C compiler. Then I expanded it torward ANSI +compliance. This C compiler is particular because each feature was +added while trying to be as simple and compact as possible. For +example, no intermediate structure is used to store code or +expressions. + +The TCC code generator directly generates linked binary code. It is +rather unusual these days (see gcc for example which generates text +assembly), but it allows to be very fast and surprisingly not so +complicated. + +The TCC code generator is register based. It means that it could even +generate good code for RISC processors. On x86, three temporary +registers are used. When more registers are needed, one register is +flushed in a new local variable. + +Constant propagation is done for all operations. Multiplications and +divisions are optimized to shifts when appropriate. Logical operators +are optimized by maintaining a special cache for the processor +flags. &&, || and ! are optimized by maintaining a special 'jmp +target' value. No other jmp optimization is currently performed +because it would require to store the code in a more abstract fashion. + +The types and values descriptions are stored in a single 'int' +variable (see VT_xxx constants). It was choosen in the first stages of +development when tcc was much simpler. Now, it may not be the best +solution. + License: ------- @@ -126,4 +157,4 @@ file). I accept only patches where you give your copyright explictely to me to simplify licensing issues. -Fabrice Bellard - Nov 11, 2001.
\ No newline at end of file +Fabrice Bellard - Nov 11, 2001. |