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authorLinus Torvalds <torvalds@linux-foundation.org>2026-09-05 11:59:05 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-09-05 11:59:05 -0700
commit9f0346dcbea363787186c94ef94dd01aaa215afa (patch)
treeb81c168f4d0dbe4c7f4750f4598d48a6deb72094 /arch/alpha/lib/strchr.S
downloadlinux-stable-9f0346dcbea363787186c94ef94dd01aaa215afa.tar.gz
linux-stable-9f0346dcbea363787186c94ef94dd01aaa215afa.zip
Merge tag 'driver-core-7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-coregrafted
Pull driver core fixes from Danilo Krummrich: - Fix kernfs listxattr() not returning security xattr names (e.g. SELinux labels) when the kernfs node has no allocated kernfs_iattrs - Fix silent truncation of IRQ vector indices in the Rust PCI abstractions - Don't select OF from DRIVER_PE_KUNIT_TEST; skip the test when OF is disabled instead of silently enabling extra kernel functionality - Russ Weight is retiring from kernel development; update the Firmware Loader sysfs contact to the driver-core mailing list, add a CREDITS entry for Firmware Upload, and update MAINTAINERS accordingly * tag 'driver-core-7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: MAINTAINERS: Remove Russ Weight from Firmware Loader CREDITS: Add CREDITS entry for Firmware Upload firmware_loader: Change contact for sysfs nodes rust: pci: reject IRQ vector indices that do not fit in u32 kernfs: preserve security xattrs without allocating iattrs drivers: base: test: DRIVER_PE_KUNIT_TEST should not select OF
Diffstat (limited to 'arch/alpha/lib/strchr.S')
-rw-r--r--arch/alpha/lib/strchr.S72
1 files changed, 72 insertions, 0 deletions
diff --git a/arch/alpha/lib/strchr.S b/arch/alpha/lib/strchr.S
new file mode 100644
index 000000000..68c54ff50
--- /dev/null
+++ b/arch/alpha/lib/strchr.S
@@ -0,0 +1,72 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * arch/alpha/lib/strchr.S
+ * Contributed by Richard Henderson (rth@tamu.edu)
+ *
+ * Return the address of a given character within a null-terminated
+ * string, or null if it is not found.
+ */
+#include <linux/export.h>
+#include <asm/regdef.h>
+
+ .set noreorder
+ .set noat
+
+ .align 3
+ .globl strchr
+ .ent strchr
+strchr:
+ .frame sp, 0, ra
+ .prologue 0
+
+ zapnot a1, 1, a1 # e0 : zero extend the search character
+ ldq_u t0, 0(a0) # .. e1 : load first quadword
+ sll a1, 8, t5 # e0 : replicate the search character
+ andnot a0, 7, v0 # .. e1 : align our loop pointer
+ or t5, a1, a1 # e0 :
+ lda t4, -1 # .. e1 : build garbage mask
+ sll a1, 16, t5 # e0 :
+ cmpbge zero, t0, t2 # .. e1 : bits set iff byte == zero
+ mskqh t4, a0, t4 # e0 :
+ or t5, a1, a1 # .. e1 :
+ sll a1, 32, t5 # e0 :
+ cmpbge zero, t4, t4 # .. e1 : bits set iff byte is garbage
+ or t5, a1, a1 # e0 :
+ xor t0, a1, t1 # .. e1 : make bytes == c zero
+ cmpbge zero, t1, t3 # e0 : bits set iff byte == c
+ or t2, t3, t0 # e1 : bits set iff char match or zero match
+ andnot t0, t4, t0 # e0 : clear garbage bits
+ bne t0, $found # .. e1 (zdb)
+
+$loop: ldq t0, 8(v0) # e0 :
+ addq v0, 8, v0 # .. e1 :
+ nop # e0 :
+ xor t0, a1, t1 # .. e1 (ev5 data stall)
+ cmpbge zero, t0, t2 # e0 : bits set iff byte == 0
+ cmpbge zero, t1, t3 # .. e1 : bits set iff byte == c
+ or t2, t3, t0 # e0 :
+ beq t0, $loop # .. e1 (zdb)
+
+$found: negq t0, t1 # e0 : clear all but least set bit
+ and t0, t1, t0 # e1 (stall)
+
+ and t0, t3, t1 # e0 : bit set iff byte was the char
+ beq t1, $retnull # .. e1 (zdb)
+
+ and t0, 0xf0, t2 # e0 : binary search for that set bit
+ and t0, 0xcc, t3 # .. e1 :
+ and t0, 0xaa, t4 # e0 :
+ cmovne t2, 4, t2 # .. e1 :
+ cmovne t3, 2, t3 # e0 :
+ cmovne t4, 1, t4 # .. e1 :
+ addq t2, t3, t2 # e0 :
+ addq v0, t4, v0 # .. e1 :
+ addq v0, t2, v0 # e0 :
+ ret # .. e1 :
+
+$retnull:
+ mov zero, v0 # e0 :
+ ret # .. e1 :
+
+ .end strchr
+ EXPORT_SYMBOL(strchr)