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Re: How long should -O1 compiles take?
- To: lucier at math dot purdue dot edu, law at cygnus dot com
- Subject: Re: How long should -O1 compiles take?
- From: Brad Lucier <lucier at math dot purdue dot edu>
- Date: Mon, 4 Oct 1999 21:18:03 -0500 (EST)
- Cc: gcc at gcc dot gnu dot org, hosking at cs dot purdue dot edu, feeley at iro dot umontreal dot ca
I said:
> Is the global register allocation that much better in gcc-2.96 that it
> should take 89 seconds now instead of 2.45 seconds as in egcs-1.1.2?
> Or is flow analysis/control so much better that gcc should be spending
> 353 seconds on it rather than 38 seconds? (I tried -fno-thread-jumps in
> gcc-2.95.1 to try to reduce the compile time, but instead it increased
> to 478.56u.)
Sorry, I worded that very poorly. What I should have said is: Do the
gcc developers want a global register allocator that takes 89 seconds
in gcc -O1, whether or not it is significantly better than the old one
that took 2.45 seconds? And the same question for other passes in
the compiler. Is there a specific design trade-off in compilation
speed/generated code speed for -O1 that decides things like this?
Brad