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Date: Tue, 20 Apr 2004 01:38:00 -0000
From: "pinskia at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Message-ID: <20040420010538.15017.pinskia@gcc.gnu.org>
Reply-To: gcc-bugzilla@gcc.gnu.org
Subject: [Bug optimization/15017] New: [tree-ssa] compare (equal) with casts are not removed
X-Bugzilla-Reason: CC
X-SW-Source: 2004-04/txt/msg01635.txt.bz2
List-Id: <gcc-bugs.sourceware.org>

On most targets where _Bool is of size 1 (everywhere except PPC-darwin), the following
code contains sign/zero extends which is bad code:

static _Bool as, bs;
_Bool foo3 (void) {
if (as != bs) return 1;
else  return 0;
}

Likewise for this code also:
static signed char as, bs;
_Bool foo3 (void) {
int as1 = as;
int bs1 = bs;
if (as1 != bs1) return 1;
else  return 0;
}

-- 
           Summary: [tree-ssa] compare (equal) with casts are not removed
           Product: gcc
           Version: tree-ssa
            Status: UNCONFIRMED
          Keywords: pessimizes-code
          Severity: enhancement
          Priority: P2
         Component: optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: pinskia at gcc dot gnu dot org
                CC: gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15017