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From:   Nam Cao <namcaov@gmail.com>
To:     Paul Walmsley <paul.walmsley@sifive.com>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Albert Ou <aou@eecs.berkeley.edu>,
        linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org
Cc:     Nam Cao <namcaov@gmail.com>
Subject: [PATCH] riscv: remove redundant mv instructions
Date:   Tue, 25 Jul 2023 07:38:35 +0200
Message-Id: <20230725053835.138910-1-namcaov@gmail.com>
MIME-Version: 1.0
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Some mv instructions were useful when first introduced to preserve a0 and
a1 before function calls. However the code has changed and they are now
redundant. Remove them.

Signed-off-by: Nam Cao <namcaov@gmail.com>
---
 arch/riscv/kernel/head.S | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
index 11c3b94c4534..3710ea5d160f 100644
--- a/arch/riscv/kernel/head.S
+++ b/arch/riscv/kernel/head.S
@@ -289,10 +289,6 @@ clear_bss:
 	blt a3, a4, clear_bss
 clear_bss_done:
 #endif
-	/* Save hart ID and DTB physical address */
-	mv s0, a0
-	mv s1, a1
-
 	la a2, boot_cpu_hartid
 	XIP_FIXUP_OFFSET a2
 	REG_S a0, (a2)
@@ -306,7 +302,7 @@ clear_bss_done:
 	la a0, __dtb_start
 	XIP_FIXUP_OFFSET a0
 #else
-	mv a0, s1
+	mv a0, a1
 #endif /* CONFIG_BUILTIN_DTB */
 	call setup_vm
 #ifdef CONFIG_MMU
-- 
2.34.1