git: 068f2402d28b - stable/13 - amd64: add a note about simd to libc memset, memmove and memcmp

[Mateusz Guzik]

The branch stable/13 has been updated by mjg:

URL: https://cgit.FreeBSD.org/src/commit/?id=068f2402d28bf2ddee884c83be1dff3a7631569b

commit 068f2402d28bf2ddee884c83be1dff3a7631569b
Author:     Mateusz Guzik <mjg at FreeBSD.org>
AuthorDate: 2021-01-31 15:50:34 +0000
Commit:     Mateusz Guzik <mjg at FreeBSD.org>
CommitDate: 2021-02-04 17:59:05 +0000

    amd64: add a note about simd to libc memset, memmove and memcmp
    
    (cherry picked from commit 0db6aef407f30c138982b8cde43189aad098b337)
---
 lib/libc/amd64/string/memcmp.S  | 6 ++++++
 lib/libc/amd64/string/memmove.S | 6 ++++++
 lib/libc/amd64/string/memset.S  | 6 ++++++
 3 files changed, 18 insertions(+)

diff --git a/lib/libc/amd64/string/memcmp.S b/lib/libc/amd64/string/memcmp.S
index 231ab2175804..67c7df280679 100644
--- a/lib/libc/amd64/string/memcmp.S
+++ b/lib/libc/amd64/string/memcmp.S
@@ -31,6 +31,12 @@
 #include <machine/asm.h>
 __FBSDID("$FreeBSD$");
 
+/*
+ * Note: this routine was written with kernel use in mind (read: no simd),
+ * it is only present in userspace as a temporary measure until something
+ * better gets imported.
+ */
+
 #define ALIGN_TEXT      .p2align 4,0x90 /* 16-byte alignment, nop filled */
 
 ENTRY(memcmp)
diff --git a/lib/libc/amd64/string/memmove.S b/lib/libc/amd64/string/memmove.S
index 4797140a1c16..3d75ff45c798 100644
--- a/lib/libc/amd64/string/memmove.S
+++ b/lib/libc/amd64/string/memmove.S
@@ -29,6 +29,12 @@
 #include <machine/asm.h>
 __FBSDID("$FreeBSD$");
 
+/*
+ * Note: this routine was written with kernel use in mind (read: no simd),
+ * it is only present in userspace as a temporary measure until something
+ * better gets imported.
+ */
+
 #define	ALIGN_TEXT	.p2align 4,0x90 /* 16-byte alignment, nop filled */
 
 /*
diff --git a/lib/libc/amd64/string/memset.S b/lib/libc/amd64/string/memset.S
index 0639573a4a3e..050711302354 100644
--- a/lib/libc/amd64/string/memset.S
+++ b/lib/libc/amd64/string/memset.S
@@ -31,6 +31,12 @@
 #include <machine/asm.h>
 __FBSDID("$FreeBSD$");
 
+/*
+ * Note: this routine was written with kernel use in mind (read: no simd),
+ * it is only present in userspace as a temporary measure until something
+ * better gets imported.
+ */
+
 #define ALIGN_TEXT      .p2align 4,0x90 /* 16-byte alignment, nop filled */
 
 .macro MEMSET erms