From: Aldy Hernandez <aldyh@redhat.com>
Date: Tue, 4 Aug 2020 04:41:03 +0000 (+0200)
Subject: Remove ad-hoc range canonicalization from determine_block_size.
X-Git-Tag: upstream/12.2.0~14427
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=f21757eb8fa74ad8a6f64cd7f9137b07f4714e11;p=platform%2Fupstream%2Fgcc.git

Remove ad-hoc range canonicalization from determine_block_size.

Anti ranges of ~[MIN,X] are automatically canonicalized to [X+1,MAX],
at creation time.  There is no need to handle them specially.

Tested by adding a gcc_unreachable and bootstrapping/testing.

gcc/ChangeLog:

	* builtins.c (determine_block_size): Remove ad-hoc range canonicalization.
---

diff --git a/gcc/builtins.c b/gcc/builtins.c
index 228db78..beb56e0 100644
--- a/gcc/builtins.c
+++ b/gcc/builtins.c
@@ -3287,12 +3287,6 @@ determine_block_size (tree len, rtx len_rtx,
 	}
       else if (range_type == VR_ANTI_RANGE)
 	{
-	  /* Anti range 0...N lets us to determine minimal size to N+1.  */
-	  if (min == 0)
-	    {
-	      if (wi::fits_uhwi_p (max) && max.to_uhwi () + 1 != 0)
-		*min_size = max.to_uhwi () + 1;
-	    }
 	  /* Code like
 
 	     int n;
@@ -3302,7 +3296,7 @@ determine_block_size (tree len, rtx len_rtx,
 	     Produce anti range allowing negative values of N.  We still
 	     can use the information and make a guess that N is not negative.
 	     */
-	  else if (!wi::leu_p (max, 1 << 30) && wi::fits_uhwi_p (min))
+	  if (!wi::leu_p (max, 1 << 30) && wi::fits_uhwi_p (min))
 	    *probable_max_size = min.to_uhwi () - 1;
 	}
     }