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Mail Archives: djgpp/2000/04/16/04:27:12

Date: Sun, 16 Apr 2000 09:56:39 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
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To: "Alexei A. Frounze" <alex DOT fru AT mtu-net DOT ru>
cc: djgpp AT delorie DOT com
Subject: Re: inefficiency of GCC output code & -O problem
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On Sat, 15 Apr 2000, Alexei A. Frounze wrote:

> Hmm, how do we really know how many values are left by GCC on the FPU stack?

I think you can't, in general, not at compile time.

However, if you get to the point where you need such an intricate
knowledge about the code generated by GCC, perhaps some reality check
is in order.  IIRC, the original motivation for your inline assembly
was to avoid the cost of a call to the `ceil' library function.
Surely there must be an easier way of doing whatever you needed `ceil'
for without knowing which part of the FP stack is in use, right?

Suppose you describe the original problem(s) which led you to use the
inline assembly in the first place, in this particular case?  Chances
are, that problem has a much simpler solution.

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