Merge branch '2021-09-24-arm64-optimized-str-funcs' into next

- Bring in, but disable by default, asm optimized string functions for
  arm64.

1 files changed, 98 insertions, 0 deletions

diff --git a/arch/arm/lib/asmdefs.h b/arch/arm/lib/asmdefs.h
new file mode 100644
index 0000000000..d307a3a8a2
--- /dev/null
+++ b/arch/arm/lib/asmdefs.h
@@ -0,0 +1,98 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Macros for asm code.
+ *
+ * Copyright (c) 2019, Arm Limited.
+ */
+
+#ifndef _ASMDEFS_H
+#define _ASMDEFS_H
+
+#if defined(__aarch64__)
+
+/* Branch Target Identitication support.  */
+#define BTI_C		hint	34
+#define BTI_J		hint	36
+/* Return address signing support (pac-ret).  */
+#define PACIASP		hint	25; .cfi_window_save
+#define AUTIASP		hint	29; .cfi_window_save
+
+/* GNU_PROPERTY_AARCH64_* macros from elf.h.  */
+#define FEATURE_1_AND 0xc0000000
+#define FEATURE_1_BTI 1
+#define FEATURE_1_PAC 2
+
+/* Add a NT_GNU_PROPERTY_TYPE_0 note.  */
+#define GNU_PROPERTY(type, value)	\
+  .section .note.gnu.property, "a";	\
+  .p2align 3;				\
+  .word 4;				\
+  .word 16;				\
+  .word 5;				\
+  .asciz "GNU";				\
+  .word type;				\
+  .word 4;				\
+  .word value;				\
+  .word 0;				\
+  .text
+
+/* If set then the GNU Property Note section will be added to
+   mark objects to support BTI and PAC-RET.  */
+#ifndef WANT_GNU_PROPERTY
+#define WANT_GNU_PROPERTY 1
+#endif
+
+#if WANT_GNU_PROPERTY
+/* Add property note with supported features to all asm files.  */
+GNU_PROPERTY (FEATURE_1_AND, FEATURE_1_BTI|FEATURE_1_PAC)
+#endif
+
+#define ENTRY_ALIGN(name, alignment)	\
+  .global name;		\
+  .type name,%function;	\
+  .align alignment;		\
+  name:			\
+  .cfi_startproc;	\
+  BTI_C;
+
+#else
+
+#define END_FILE
+
+#define ENTRY_ALIGN(name, alignment)	\
+  .global name;		\
+  .type name,%function;	\
+  .align alignment;		\
+  name:			\
+  .cfi_startproc;
+
+#endif
+
+#define ENTRY(name)	ENTRY_ALIGN(name, 6)
+
+#define ENTRY_ALIAS(name)	\
+  .global name;		\
+  .type name,%function;	\
+  name:
+
+#define END(name)	\
+  .cfi_endproc;		\
+  .size name, .-name;
+
+#define L(l) .L ## l
+
+#ifdef __ILP32__
+  /* Sanitize padding bits of pointer arguments as per aapcs64 */
+#define PTR_ARG(n)  mov w##n, w##n
+#else
+#define PTR_ARG(n)
+#endif
+
+#ifdef __ILP32__
+  /* Sanitize padding bits of size arguments as per aapcs64 */
+#define SIZE_ARG(n)  mov w##n, w##n
+#else
+#define SIZE_ARG(n)
+#endif
+
+#endif