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From: "xinliangli at gmail dot com" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug middle-end/35363] New: Missing bit field coalscing optimization Date: Mon, 25 Feb 2008 05:39:00 -0000 [thread overview] Message-ID: <bug-35363-9436@http.gcc.gnu.org/bugzilla/> (raw) // David Li struct A{ int b1: 3; int b2: 3; int b3: 2; int b4: 17; }a; void foo() { a.b1 = 2; a.b2 = 3; a.b4 = 8; } This requires one LOAD + one OR + one STORE, but the generate code looks like: foo: .LFB2: movzbl a(%rip), %eax andl $-64, %eax orl $26, %eax movb %al, a(%rip) movl a(%rip), %eax andl $-33554177, %eax orb $8, %ah movl %eax, a(%rip) ret -- Summary: Missing bit field coalscing optimization Product: gcc Version: unknown Status: UNCONFIRMED Severity: normal Priority: P3 Component: middle-end AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: xinliangli at gmail dot com http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35363
next reply other threads:[~2008-02-25 5:39 UTC|newest] Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top 2008-02-25 5:39 xinliangli at gmail dot com [this message] 2008-02-25 11:37 ` [Bug middle-end/35363] " rguenth at gcc dot gnu dot org 2008-02-25 18:39 ` [Bug target/35363] " pinskia at gcc dot gnu dot org 2008-02-25 18:45 ` [Bug target/35363] Missing bit field coalescing optimization rguenth at gcc dot gnu dot org 2008-02-25 18:50 ` rguenth at gcc dot gnu dot org 2008-02-25 18:52 ` rguenth at gcc dot gnu dot org 2008-02-25 18:54 ` rguenth at gcc dot gnu dot org
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