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From: Andreas Schwab <schwab@suse.de>
To: caiyinyu <caiyinyu@loongson.cn>
Cc: Xi Ruoyao <xry111@xry111.site>,
	 libc-alpha@sourceware.org, adhemerval.zanella@linaro.org
Subject: Re: [PATCH] LoongArch: Add Syscall Assembly Implementation
Date: Thu, 23 Mar 2023 14:12:00 +0100	[thread overview]
Message-ID: <mvmjzz7wr1b.fsf@suse.de> (raw)
In-Reply-To: <8a4e2e72-9daf-d264-f49d-719daa2407b5@loongson.cn> (caiyinyu@loongson.cn's message of "Thu, 23 Mar 2023 20:01:18 +0800")

On Mär 23 2023, caiyinyu wrote:

> Without this patch(objdump -d libc.so...):
>
> 00000000000dd45c <syscall>:
>    dd45c:       02fec063        addi.d          $sp, $sp, -80(0xfb0)
>    dd460:       02c0606c        addi.d          $t0, $sp, 24(0x18)
>    dd464:       29c06065        st.d            $a1, $sp, 24(0x18)
>    dd468:       29c08066        st.d            $a2, $sp, 32(0x20)
>    dd46c:       29c0a067        st.d            $a3, $sp, 40(0x28)
>    dd470:       29c0c068        st.d            $a4, $sp, 48(0x30)
>    dd474:       29c0e069        st.d            $a5, $sp, 56(0x38)
>    dd478:       29c1206b        st.d            $a7, $sp, 72(0x48)
>    dd47c:       29c1006a        st.d            $a6, $sp, 64(0x40)

If the argument registers are call-clobbbered, why does the compiler
need to save them?

-- 
Andreas Schwab, SUSE Labs, schwab@suse.de
GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE  1748 E4D4 88E3 0EEA B9D7
"And now for something completely different."

  reply	other threads:[~2023-03-23 13:12 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-03-23  8:40 caiyinyu
2023-03-23  9:25 ` Xi Ruoyao
2023-03-23 12:01   ` caiyinyu
2023-03-23 13:12     ` Andreas Schwab [this message]
2023-03-23 13:34       ` Xi Ruoyao
2023-03-23 13:43         ` Xi Ruoyao
2023-03-23 17:34           ` Xi Ruoyao
2023-03-23 18:26             ` Xi Ruoyao
2023-03-23 18:40               ` Adhemerval Zanella Netto
2023-03-23 19:08                 ` Xi Ruoyao
2023-03-23 13:12     ` Xi Ruoyao
2023-03-23 12:00 caiyinyu

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