From: Richard Biener <rguenther@suse.de>
Date: Tue, 24 Sep 2024 12:23:40 +0000 (+0200)
Subject: Simplify range-op shift mask generation
X-Git-Tag: basepoints/gcc-16~5720
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2114243c23ec5168cd54633cd4995ab123d92573;p=thirdparty%2Fgcc.git

Simplify range-op shift mask generation

The following reduces the number of wide_ints built which show up
in the profile for PR114855 as the largest remaining bit at -O1.

	* range-op.cc (operator_rshift::op1_range): Use wi::mask instead
	of shift and not.
---

diff --git a/gcc/range-op.cc b/gcc/range-op.cc
index c576f688221..3f5cf083440 100644
--- a/gcc/range-op.cc
+++ b/gcc/range-op.cc
@@ -2863,7 +2863,7 @@ operator_rshift::op1_range (irange &r,
       // OP1 is anything from 0011 1000 to 0011 1111.  That is, a
       // range from LHS<<3 plus a mask of the 3 bits we shifted on the
       // right hand side (0x07).
-      wide_int mask = wi::bit_not (wi::lshift (wi::minus_one (prec), shift));
+      wide_int mask = wi::mask (shift.to_uhwi (), false, prec);
       int_range_max mask_range (type,
 				wi::zero (TYPE_PRECISION (type)),
 				mask);