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authorAndi Shyti <andi.shyti@linux.intel.com>2026-08-22 14:19:12 +0200
committerAndi Shyti <andi.shyti@linux.intel.com>2026-08-22 14:19:34 +0200
commitd576a9561a1c80ae593539fb0ce0743d66825ac2 (patch)
tree68f6de7e06b350afa42edeea2f7f33f086014597 /arch/alpha/lib/strlen.S
downloadlinux-stable-d576a9561a1c80ae593539fb0ce0743d66825ac2.tar.gz
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Merge tag 'rust-i2c-for-7.3' into i2c/i2cgrafted
i2c: rust: mark I2cAdapter methods as inline A single cleanup for the Rust I2C abstractions, targeting 7.3. `I2cAdapter::get`, `inc_ref`, and `dec_ref` are trivial wrappers around `i2c_get_adapter`/`i2c_put_adapter` and were showing up as their own symbols in the build. Mark them `#[inline]` so they get folded into their callers instead. Signed-off-by: Igor Korotin <igor.korotin@linux.dev> * tag 'rust-i2c-for-7.3': i2c: rust: mark I2cAdapter methods as inline
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diff --git a/arch/alpha/lib/strlen.S b/arch/alpha/lib/strlen.S
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+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * strlen.S (c) 1995 David Mosberger (davidm@cs.arizona.edu)
+ *
+ * Finds length of a 0-terminated string. Optimized for the
+ * Alpha architecture:
+ *
+ * - memory accessed as aligned quadwords only
+ * - uses bcmpge to compare 8 bytes in parallel
+ * - does binary search to find 0 byte in last
+ * quadword (HAKMEM needed 12 instructions to
+ * do this instead of the 9 instructions that
+ * binary search needs).
+ */
+#include <linux/export.h>
+ .set noreorder
+ .set noat
+
+ .align 3
+
+ .globl strlen
+ .ent strlen
+
+strlen:
+ ldq_u $1, 0($16) # load first quadword ($16 may be misaligned)
+ lda $2, -1($31)
+ insqh $2, $16, $2
+ andnot $16, 7, $0
+ or $2, $1, $1
+ cmpbge $31, $1, $2 # $2 <- bitmask: bit i == 1 <==> i-th byte == 0
+ bne $2, found
+
+loop: ldq $1, 8($0)
+ addq $0, 8, $0 # addr += 8
+ nop # helps dual issue last two insns
+ cmpbge $31, $1, $2
+ beq $2, loop
+
+found: blbs $2, done # make aligned case fast
+ negq $2, $3
+ and $2, $3, $2
+
+ and $2, 0x0f, $1
+ addq $0, 4, $3
+ cmoveq $1, $3, $0
+
+ and $2, 0x33, $1
+ addq $0, 2, $3
+ cmoveq $1, $3, $0
+
+ and $2, 0x55, $1
+ addq $0, 1, $3
+ cmoveq $1, $3, $0
+
+done: subq $0, $16, $0
+ ret $31, ($26)
+
+ .end strlen
+ EXPORT_SYMBOL(strlen)