Re: Suppressing code motion of constant values...

Re: Suppressing code motion of constant values...

[Joern Rennecke]

> There was a code snippet and discussion of the idea of
> suppressing hoisting constants outside of loops at
> lower optimization levels.
> 
> I thought at the time that this wasn't a winner for me, but in
> looking at some generated code for the SHARC DSP chip, it
> appears that this is causing me to use more registers than
> I need.
> 
> Can someone resend that code fragment?  It was a patch to loop.c
> if I remember correctly.

----- Forwarded message from Joern Rennecke -----

Re: Suppressing code motion of constant values...

[Jim Wilson]

It was a suggestion for the -Os (optimize for space) option, not one of
the speed optimization options.

The message was posted 03/30 by Joern Rennecke, with subject line
"New size optimization".

Jim

Re: Suppressing code motion of constant values...

[Jeffrey A Law]

  In message < l03130300b1665719a9bd@[209.61.104.176] >you write:
  > 
  > There was a code snippet and discussion of the idea of
  > suppressing hoisting constants outside of loops at
  > lower optimization levels.
  > 
  > I thought at the time that this wasn't a winner for me, but in
  > looking at some generated code for the SHARC DSP chip, it
  > appears that this is causing me to use more registers than
  > I need.
  > 
  > Can someone resend that code fragment?  It was a patch to loop.c
  > if I remember correctly.
It was a patch to loop and you should be able to find it in the
archives.  Probably the best way would be to use the by

Suppressing code motion of constant values...

[Alan Lehotsky]

There was a code snippet and discussion of the idea of
suppressing hoisting constants outside of loops at
lower optimization levels.

I thought at the time that this wasn't a winner for me, but in
looking at some generated code for the SHARC DSP chip, it
appears that this is causing me to use more registers than
I need.

Can someone resend that code fragment?  It was a patch to loop.c
if I remember correctly.

-- Al Lehotsky



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