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Re: GCC beaten by ICC in stupid trig test!
- From: Roger Sayle <roger at eyesopen dot com>
- To: Bradley Lucier <lucier at math dot purdue dot edu>, Toon Moene <toon at moene dot indiv dot nluug dot nl>, Scott Robert Ladd <coyote at coyotegulch dot com>
- Cc: gcc at gcc dot gnu dot org, <gcc-patches at gcc dot gnu dot org>
- Date: Wed, 24 Mar 2004 14:00:08 -0700 (MST)
- Subject: Re: GCC beaten by ICC in stupid trig test!
May I remind everyone that the subject title "GCC beaten by ICC in
stupid trig test!" refers to a posting by Scott Robert Ladd in which
Intel's icc compiler generates floating point code 64x faster than
gcc 3.3.3 (http://gcc.gnu.org/ml/gcc/2004-03/msg00634.html).
Would anyone like to hazard a guess at how many floating point additions
Intel icc v7 generates for the following function? Even with icc's
default arguments, i.e. "icc foo.c"?
int foo(double a, double b, double c)
return (a+b)+c == a+(b+c);
It might surprise some people that even with -funsafe-math-optimizations
and/or -ffast-math GCC can't generate code with that performance/accuracy