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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/84251] [11/12/13/14 Regression] Performance regression in gcc 8/9/10/11/12 when comparing floating point numbers
Date: Fri, 04 Aug 2023 00:50:59 +0000 [thread overview]
Message-ID: <bug-84251-4-eO6PGQ02BB@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-84251-4@http.gcc.gnu.org/bugzilla/>
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84251
--- Comment #20 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Hmm: we have:
```
(jump_insn 8 7 9 2 (set (pc)
(if_then_else (ordered (reg:CCFP 17 flags)
(const_int 0 [0]))
(label_ref 12)
(pc))) "/app/example.cpp":5:6 1055 {*jcc}
(expr_list:REG_DEAD (reg:CCFP 17 flags)
(int_list:REG_BR_PROB 1073741831 (nil)))
-> 12)
(note 9 8 10 3 [bb 3] NOTE_INSN_BASIC_BLOCK)
(call_insn 10 9 12 3 (call (mem:QI (symbol_ref:DI ("abort") [flags 0x41]
<function_decl 0x7f2aa863b500 __builtin_abort>) [0 __builtin_abort S1 A8])
(const_int 0 [0])) "/app/example.cpp":6:5 1062 {*call}
(expr_list:REG_CALL_DECL (symbol_ref:DI ("abort") [flags 0x41]
<function_decl 0x7f2aa863b500 __builtin_abort>)
(expr_list:REG_ARGS_SIZE (const_int 0 [0])
(expr_list:REG_NORETURN (const_int 0 [0])
(expr_list:REG_EH_REGION (const_int 0 [0])
(nil)))))
(nil))
(code_label 12 10 13 4 2 (nil) [1 uses])
(note 13 12 15 4 [bb 4] NOTE_INSN_BASIC_BLOCK)
(insn 15 13 16 4 (set (reg:QI 91)
(ordered:QI (reg:CCFP 17 flags)
(const_int 0 [0]))) "/app/example.cpp":7:12 1050 {*setcc_qi}
(expr_list:REG_DEAD (reg:CCFP 17 flags)
(nil)))
```
We know in insn 16 at this point (ordered:QI (reg:CCFP 17 flags) (const_int 0
[0])) is 1. Isn't there a pass which does that?
Or is it because the differences in the modes (VOIDmode vs QImode) causing that
not to happen?
prev parent reply other threads:[~2023-08-04 0:51 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <bug-84251-4@http.gcc.gnu.org/bugzilla/>
2021-05-14 9:49 ` [Bug target/84251] [9/10/11/12 " jakub at gcc dot gnu.org
2021-06-01 8:10 ` rguenth at gcc dot gnu.org
2022-05-27 9:38 ` [Bug target/84251] [10/11/12/13 " rguenth at gcc dot gnu.org
2022-06-28 10:34 ` jakub at gcc dot gnu.org
2023-05-30 7:33 ` [Bug target/84251] [10/11/12/13/14 " pinskia at gcc dot gnu.org
2023-07-07 10:33 ` [Bug target/84251] [11/12/13/14 " rguenth at gcc dot gnu.org
2023-08-04 0:50 ` pinskia at gcc dot gnu.org [this message]
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