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Re: Building current



On Sun, Apr 07, 2013 at 10:18:12AM -0400, Mouse wrote:
> which disassembles to
> 
>     ashq    -04(fp),$00000000ffffffff,-0c(fp)

I thought it would be emited by the vax_output_int_move() function in
src/gnu/dist/gcc4/gcc/config/vax/vax.c line 1051ff:

          /* Here we see if we are trying to see if the 64bit value is really
             a 6bit shifted some arbitrary amount.  If so, we can use ashq to
             shift it to the correct value saving 7 bytes (1 addr-mode-byte +
             8 bytes - 1 shift byte - 1 short literal byte.  */

which has a special case for 0:

              /*  If n is 0, then ashq is not the best way to emit this.  */ 

but that would suggest it should not use ashq here, so something else must
be going on.

This code path has not changed in years, or so it seems.

Martin


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