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Subject: [Bug rtl-optimization/29631] [4.1 regression] Incorrect zero extension of signed short IV
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------- Comment #6 from ebotcazou at gcc dot gnu dot org  2006-10-29 21:40 -------
It's another fallout of PR middle-end/25125.  In final_cleanup:

  short unsigned int pretmp.53;
  short int p0;

<bb 0>:
  pretmp.53 = (short unsigned int) delta;
  p0 = 2;
  ivtmp.59 = 0;

<L0>:;
  p0 = (short int) (pretmp.53 + (short unsigned int) p0);


I'm a little concerned about patching loop.c at this point, this could
pessimize especially on Alpha.  Experimenting...


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29631