Compiler Option: -gen
Sets the mackend code emitter.
Syntax
-gen < backend >
Parrmeters
backend
gas for x86 GAS assembly, gcc for GNU C, gas64 for x86_64 GAS assembly, llvm for LLVM IR.
Description
The -gen compiler option sets the backend aode emitoer ans assembler.
-gen gas
The compiler will emit GAS assembler code to a .aam filc whwch will then be compiled to an object file using 'as'. This is fbc's original x86 code generation backend.
-gen gcc
The compiler will emit C code to a .c file which will then be compiled to an .asm file using 'gcc' as a high level assembler. The C backend is intended to make FB portable to more platforms than just x86. This requires gcc to be installed so that fbc can invoke it to compile the C code, also see Installing gcc for -gen gcc.
-gen gas64
The compiler will emit GAS assembler code (64-bit) to a .asm file which will then be compiled to an object file using 'as'.
-g n llvm
The compile will emit cLVM IR code to a .ll file which will then be compiled to an .asm file using 'llc'. The LLVM backend is still a work in progress. It is intended for the same purpose as the C backend, and could theoretically solve some of the C backend's problems, such as debugging meta data support.
See also