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From: "vmakarov at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/66334] cleanup block fails to initialize EBX
Date: Fri, 03 Jul 2015 17:25:00 -0000 [thread overview]
Message-ID: <bug-66334-4-PatlK38Y1i@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-66334-4@http.gcc.gnu.org/bugzilla/>
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66334
Vladimir Makarov <vmakarov at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |vmakarov at gcc dot gnu.org
--- Comment #7 from Vladimir Makarov <vmakarov at gcc dot gnu.org> ---
(In reply to H.J. Lu from comment #2)
> After IRA,
>
> (insn 34 33 35 5 (set (reg:SI 3 bx)
> (reg:SI 87)) 86 {*movsi_internal}
> (expr_list:REG_DEAD (reg:SI 87)
> (nil)))
> (call_insn 35 34 36 5 (call (mem:QI (symbol_ref:SI ("_Unwind_Resume") [flags
> 0x41] <function_decl 0x7f1f9f3005e8 __builtin_unwind_resume>) [0
> __builtin_unwind_resume S1 A8])
> (const_int 16 [0x10])) 649 {*call}
> (expr_list:REG_DEAD (reg:SI 3 bx)
> (expr_list:REG_CALL_DECL (symbol_ref:SI ("_Unwind_Resume") [flags
> 0x41] <function_decl 0x7f1f9f3005e8 __builtin_unwind_resume>)
> (expr_list:REG_ARGS_SIZE (const_int 16 [0x10])
> (expr_list:REG_NORETURN (const_int 0 [0])
> (nil)))))
> (expr_list (use (reg:SI 3 bx))
> (nil)))
>
> LRA removed:
>
> (insn 34 33 35 5 (set (reg:SI 3 bx)
> (reg:SI 87)) 86 {*movsi_internal}
> (expr_list:REG_DEAD (reg:SI 87)
> (nil)))
>
> LRA should recognize that BUILT_IN_UNWIND_RESUME and initialize EBX.
I've looked at this. Insn 34 is transformed into
ebx=ebx
as pseudo 87 gets ebx. At the very end. LRA removes the useless insn.
Therefore there is no insn setting ebx.
H.J., is it really a problem?
next prev parent reply other threads:[~2015-07-03 17:25 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-05-29 2:50 [Bug middle-end/66334] New: " hjl.tools at gmail dot com
2015-05-29 2:56 ` [Bug middle-end/66334] " hjl.tools at gmail dot com
2015-05-29 20:37 ` hjl.tools at gmail dot com
2015-05-29 21:54 ` hjl.tools at gmail dot com
2015-05-29 21:55 ` hjl.tools at gmail dot com
2015-05-31 13:16 ` hjl.tools at gmail dot com
2015-06-01 14:21 ` hjl.tools at gmail dot com
2015-07-03 17:25 ` vmakarov at gcc dot gnu.org [this message]
2015-07-03 18:42 ` hjl.tools at gmail dot com
2015-07-03 21:04 ` vmakarov at gcc dot gnu.org
2015-07-04 13:57 ` hjl.tools at gmail dot com
2015-07-07 19:35 ` vmakarov at gcc dot gnu.org
2015-07-08 15:05 ` vmakarov at gcc dot gnu.org
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