Compiler: TDA2xx DSP - compiling a file take a very long time

The two main reasons that compilation takes a long time are size and complexity.  Big things take longer, sometimes out of proportion to their size.  Complex things take longer, where "complex" is not always apparent from the source -- it could be a mess of cross-dependences or a series of assignments that can be combined into one giant expression or some weird combination that happens to be pathological.

How much inlining is happening?  If these functions are inlined in many places, you could be creating something large.  I think that the --gen_opt_info=2 option will indicate which call sites are inlined.  The --keep_asm option will keep the .asm file from the compilation;  at the end is a section that lists the functions that are inlined, kind of like footnotes.  If too much inlining is the problem, there are several approaches;  which to use depends on the version of the compiler.

Do the loops have known constant trip counts?  If the counts are small enough, the loops might be unrolled completely.  The idea is to allow for more software pipelining, but the compiler sometimes slows itself down in the pursuit of small speedups.  Try adding "#pragma UNROLL(1)" before each of the for-loops -- that will inhibit unrolling.  If that helps, then over-unrolling is the issue.  You may need to adjust the unroll amount to achieve the speed you want.

If neither of these ideas helps, then we're just going to have to have a test case.  Your code might be triggering something complex, which we might be able to avoid by either modifying the code or changing the compiler, but there's no way to tell from what we've seen so far.