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From:   Chen Zhongjin <chenzhongjin@huawei.com>
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Subject: [PATCH v5 26/33] arm64: crypto: Remove unnecessary stackframe
Date:   Wed, 22 Jun 2022 23:49:13 +0800
Message-ID: <20220622154920.95075-27-chenzhongjin@huawei.com>
In-Reply-To: <20220622154920.95075-1-chenzhongjin@huawei.com>
References: <20220622154920.95075-1-chenzhongjin@huawei.com>
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The way sha256_block_neon restore the stackframe confuses objtool.
But it turns out this function is a leaf function and does not use
FP nor LR as scratch register.

Do not create a stackframe in this function as it is not necessary.

Signed-off-by: Julien Thierry <jthierry@redhat.com>
Signed-off-by: Chen Zhongjin <chenzhongjin@huawei.com>
---
 arch/arm64/crypto/sha512-armv8.pl | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/arch/arm64/crypto/sha512-armv8.pl b/arch/arm64/crypto/sha512-armv8.pl
index 1882c4110026..6e2a96e05c5a 100644
--- a/arch/arm64/crypto/sha512-armv8.pl
+++ b/arch/arm64/crypto/sha512-armv8.pl
@@ -648,8 +648,6 @@ $code.=<<___;
 .align	4
 sha256_block_neon:
 .Lneon_entry:
-	stp	x29, x30, [sp, #-16]!
-	mov	x29, sp
 	sub	sp,sp,#16*4
 
 	adr	$Ktbl,K256
@@ -736,8 +734,7 @@ $code.=<<___;
 	 mov	$Xfer,sp
 	b.ne	.L_00_48
 
-	ldr	x29,[x29]
-	add	sp,sp,#16*4+16
+	add	sp,sp,#16*4
 	ret
 .size	sha256_block_neon,.-sha256_block_neon
 ___
-- 
2.17.1