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From: "socketpair at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug regression/107767] GCC has some problems in optimizer of trivial case
Date: Sun, 20 Nov 2022 13:02:32 +0000 [thread overview]
Message-ID: <bug-107767-4-O3vhi4wnRO@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-107767-4@http.gcc.gnu.org/bugzilla/>
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107767
--- Comment #1 from Коренберг Марк <socketpair at gmail dot com> ---
See assembler output for firewall2(). It's not -Os optimized (compare to
firewall(), which is ok)
```
firewall:
movw 64(%rdi), %ax
cmpb $17, (%rdi)
sete %cl
leal -15(%rax), %edx
testw $-9, %dx
movb $1, %dl
sete %sil
cmpw $47, %ax
ja .L2
movabsq $-180319906955279, %rdx
btq %rax, %rdx
setc %dl
.L2:
movl %edx, %eax
xorl $1, %eax
orl %esi, %eax
andl %ecx, %eax
movzbl %al, %eax
ret
firewall2:
movw 64(%rdi), %ax
xorl %edx, %edx
decl %eax
cmpw $46, %ax
ja .L5
movzwl %ax, %eax
movsbl CSWTCH.2(%rax), %edx
.L5:
movl %edx, %eax
ret
CSWTCH.2:
.byte 1
.byte 1
.byte 1
.byte 0
.byte 0
.byte 0
.byte 0
.byte 0
.byte 0
.byte 0
.byte 0
.byte 0
.byte 0
.byte 0
.byte 1
.byte 0
.byte 0
.byte 0
.byte 0
.byte 0
.byte 0
.byte 0
.byte 1
.byte 0
.byte 0
.byte 0
.byte 0
.byte 0
.byte 0
.byte 0
.byte 0
.byte 0
.byte 0
.byte 0
.byte 0
.byte 0
.byte 0
.byte 0
.byte 0
.byte 0
.byte 0
.byte 1
.byte 0
.byte 0
.byte 1
.byte 0
.byte 1
```
next prev parent reply other threads:[~2022-11-20 13:02 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-11-20 13:00 [Bug regression/107767] New: " socketpair at gmail dot com
2022-11-20 13:02 ` socketpair at gmail dot com [this message]
2022-11-21 8:46 ` [Bug regression/107767] " marxin at gcc dot gnu.org
2022-11-21 10:33 ` socketpair at gmail dot com
2022-11-21 15:57 ` [Bug tree-optimization/107767] [13 Regression] " pinskia at gcc dot gnu.org
2022-12-02 14:27 ` [Bug tree-optimization/107767] [13 Regression] switch to table conversion happening even though using btq is better marxin at gcc dot gnu.org
2022-12-02 14:54 ` socketpair at gmail dot com
2022-12-02 15:00 ` marxin at gcc dot gnu.org
2022-12-02 15:07 ` marxin at gcc dot gnu.org
2022-12-02 15:15 ` socketpair at gmail dot com
2022-12-02 15:17 ` jakub at gcc dot gnu.org
2022-12-02 15:27 ` rguenth at gcc dot gnu.org
2022-12-02 15:31 ` jakub at gcc dot gnu.org
2022-12-02 15:44 ` jakub at gcc dot gnu.org
2022-12-05 14:49 ` marxin at gcc dot gnu.org
2022-12-21 9:46 ` rguenth at gcc dot gnu.org
2022-12-23 14:05 ` marxin at gcc dot gnu.org
2023-01-04 14:26 ` jakub at gcc dot gnu.org
2023-01-06 12:36 ` marxin at gcc dot gnu.org
2023-01-09 10:02 ` rguenth at gcc dot gnu.org
2023-01-11 12:14 ` cvs-commit at gcc dot gnu.org
2023-01-11 12:14 ` rguenth at gcc dot gnu.org
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