mirror of
https://github.com/ivoszbg/uniLoader.git
synced 2024-11-24 13:10:09 +00:00
lib: unic: Optimize memcpy and memset for aarch64
Move onto using asmdefs macros in assembly files. Implement an assembly-based memcpy for aarch64 and a C-optimized memset, while also making place for replacing functions with more optimized ones in the future. Signed-off-by: Ivaylo Ivanov <ivo.ivanov.ivanov1@gmail.com>
This commit is contained in:
Ivaylo Ivanov
parent
81d26edaa3
commit
784bfd609a
8
Makefile
8
Makefile
@ -344,6 +344,10 @@ all: arch/$(ARCH)/linker.lds uniLoader
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main-y := arch/$(ARCH)/start.o \
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main/main.o
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ifeq ($(ARCH), aarch64)
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arch-libs-y := arch/$(ARCH)/memcpy.o
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endif
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# Object directories
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objs-y := main
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objs-y += arch
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@ -354,8 +358,6 @@ libs-y += board
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libs-y += lib
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libs-y += drivers
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# Include these in the build process as we
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uniLoader-dirs := $(objs-y) $(libs-y)
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uniLoader-objs := $(patsubst %,%/built-in.o, $(objs-y))
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uniLoader-libs := $(patsubst %,%/lib.a, $(libs-y))
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@ -367,7 +369,7 @@ uniLoader-all := $(uniLoader-objs) $(uniLoader-libs)
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# Do modpost on a prelinked vmlinux. The finally linked vmlinux has
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# relevant sections renamed as per the linker script.
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quiet_cmd_uniLoader = LD $@.o
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cmd_uniLoader = $(LD) $(main-y) $(uniLoader-libs) -o $@.o --script=arch/$(ARCH)/linker.lds
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cmd_uniLoader = $(LD) $(main-y) $(arch-libs-y) $(uniLoader-libs) -o $@.o --script=arch/$(ARCH)/linker.lds
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arch/$(ARCH)/linker.lds: arch/$(ARCH)/linker.lds.S $(KERNEL_PATH)
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$(CPP) $< -DTEXT_BASE=$(TEXT_BASE) -DKERNEL_PATH=$(KERNEL_PATH) -DDTB_PATH=$(DT_PATH) -P -o $@
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@ -1 +1,4 @@
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obj-y += $(ARCH)/start.o
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# libs
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obj-y += $(ARCH)/memcpy.o
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106
arch/aarch64/asmdefs.h
Normal file
106
arch/aarch64/asmdefs.h
Normal file
@ -0,0 +1,106 @@
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/*
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* Macros for asm code. AArch64 version.
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*
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* Copyright (c) 2019-2023, Arm Limited.
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* SPDX-License-Identifier: MIT OR Apache-2.0 WITH LLVM-exception
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*/
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#ifndef _ASMDEFS_H
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#define _ASMDEFS_H
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/* Branch Target Identitication support. */
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#define BTI_C hint 34
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#define BTI_J hint 36
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/* Return address signing support (pac-ret). */
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#define PACIASP hint 25; .cfi_window_save
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#define AUTIASP hint 29; .cfi_window_save
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/* GNU_PROPERTY_AARCH64_* macros from elf.h. */
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#define FEATURE_1_AND 0xc0000000
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#define FEATURE_1_BTI 1
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#define FEATURE_1_PAC 2
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/* Add a NT_GNU_PROPERTY_TYPE_0 note. */
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#ifdef __ILP32__
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#define GNU_PROPERTY(type, value) \
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.section .note.gnu.property, "a"; \
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.p2align 2; \
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.word 4; \
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.word 12; \
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.word 5; \
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.asciz "GNU"; \
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.word type; \
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.word 4; \
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.word value; \
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.text
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#else
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#define GNU_PROPERTY(type, value) \
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.section .note.gnu.property, "a"; \
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.p2align 3; \
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.word 4; \
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.word 16; \
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.word 5; \
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.asciz "GNU"; \
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.word type; \
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.word 4; \
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.word value; \
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.word 0; \
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.text
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#endif
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/* If set then the GNU Property Note section will be added to
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mark objects to support BTI and PAC-RET. */
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#ifndef WANT_GNU_PROPERTY
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#define WANT_GNU_PROPERTY 1
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#endif
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#if WANT_GNU_PROPERTY
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/* Add property note with supported features to all asm files. */
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GNU_PROPERTY (FEATURE_1_AND, FEATURE_1_BTI|FEATURE_1_PAC)
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#endif
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#define ENTRY_ALIGN(name, alignment) \
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.global name; \
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.type name,%function; \
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.align alignment; \
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name: \
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.cfi_startproc; \
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BTI_C;
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#define ENTRY(name) ENTRY_ALIGN(name, 6)
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#define ENTRY_ALIAS(name) \
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.global name; \
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.type name,%function; \
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name:
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#define END(name) \
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.cfi_endproc; \
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.size name, .-name;
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#define L(l) .L ## l
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#ifdef __ILP32__
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/* Sanitize padding bits of pointer arguments as per aapcs64 */
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#define PTR_ARG(n) mov w##n, w##n
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#else
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#define PTR_ARG(n)
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#endif
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#ifdef __ILP32__
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/* Sanitize padding bits of size arguments as per aapcs64 */
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#define SIZE_ARG(n) mov w##n, w##n
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#else
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#define SIZE_ARG(n)
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#endif
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/* Compiler supports SVE instructions */
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#ifndef HAVE_SVE
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# if __aarch64__ && (__GNUC__ >= 8 || __clang_major__ >= 5)
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# define HAVE_SVE 1
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# else
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# define HAVE_SVE 0
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# endif
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#endif
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#endif
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242
arch/aarch64/memcpy.S
Normal file
242
arch/aarch64/memcpy.S
Normal file
@ -0,0 +1,242 @@
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/*
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* memcpy - copy memory area
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*
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* Copyright (c) 2012-2022, Arm Limited.
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* SPDX-License-Identifier: MIT OR Apache-2.0 WITH LLVM-exception
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*/
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/* Assumptions:
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*
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* ARMv8-a, AArch64, unaligned accesses.
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*
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*/
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#include "asmdefs.h"
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#define dstin x0
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#define src x1
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#define count x2
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#define dst x3
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#define srcend x4
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#define dstend x5
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#define A_l x6
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#define A_lw w6
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#define A_h x7
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#define B_l x8
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#define B_lw w8
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#define B_h x9
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#define C_l x10
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#define C_lw w10
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#define C_h x11
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#define D_l x12
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#define D_h x13
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#define E_l x14
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#define E_h x15
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#define F_l x16
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#define F_h x17
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#define G_l count
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#define G_h dst
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#define H_l src
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#define H_h srcend
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#define tmp1 x14
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/* This implementation handles overlaps and supports both memcpy and memmove
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from a single entry point. It uses unaligned accesses and branchless
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sequences to keep the code small, simple and improve performance.
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Copies are split into 3 main cases: small copies of up to 32 bytes, medium
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copies of up to 128 bytes, and large copies. The overhead of the overlap
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check is negligible since it is only required for large copies.
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Large copies use a software pipelined loop processing 64 bytes per iteration.
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The destination pointer is 16-byte aligned to minimize unaligned accesses.
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The loop tail is handled by always copying 64 bytes from the end.
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*/
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ENTRY_ALIAS (memmove)
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ENTRY (memcpy)
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PTR_ARG (0)
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PTR_ARG (1)
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SIZE_ARG (2)
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add srcend, src, count
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add dstend, dstin, count
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cmp count, 128
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b.hi L(copy_long)
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cmp count, 32
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b.hi L(copy32_128)
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/* Small copies: 0..32 bytes. */
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cmp count, 16
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b.lo L(copy16)
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ldp A_l, A_h, [src]
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ldp D_l, D_h, [srcend, -16]
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stp A_l, A_h, [dstin]
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stp D_l, D_h, [dstend, -16]
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ret
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/* Copy 8-15 bytes. */
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L(copy16):
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tbz count, 3, L(copy8)
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ldr A_l, [src]
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ldr A_h, [srcend, -8]
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str A_l, [dstin]
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str A_h, [dstend, -8]
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ret
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.p2align 3
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/* Copy 4-7 bytes. */
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L(copy8):
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tbz count, 2, L(copy4)
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ldr A_lw, [src]
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ldr B_lw, [srcend, -4]
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str A_lw, [dstin]
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str B_lw, [dstend, -4]
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ret
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/* Copy 0..3 bytes using a branchless sequence. */
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L(copy4):
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cbz count, L(copy0)
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lsr tmp1, count, 1
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ldrb A_lw, [src]
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ldrb C_lw, [srcend, -1]
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ldrb B_lw, [src, tmp1]
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strb A_lw, [dstin]
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strb B_lw, [dstin, tmp1]
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strb C_lw, [dstend, -1]
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L(copy0):
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ret
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.p2align 4
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/* Medium copies: 33..128 bytes. */
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L(copy32_128):
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ldp A_l, A_h, [src]
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ldp B_l, B_h, [src, 16]
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ldp C_l, C_h, [srcend, -32]
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ldp D_l, D_h, [srcend, -16]
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cmp count, 64
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b.hi L(copy128)
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stp A_l, A_h, [dstin]
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stp B_l, B_h, [dstin, 16]
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stp C_l, C_h, [dstend, -32]
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stp D_l, D_h, [dstend, -16]
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ret
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.p2align 4
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/* Copy 65..128 bytes. */
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L(copy128):
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ldp E_l, E_h, [src, 32]
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ldp F_l, F_h, [src, 48]
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cmp count, 96
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b.ls L(copy96)
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ldp G_l, G_h, [srcend, -64]
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ldp H_l, H_h, [srcend, -48]
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stp G_l, G_h, [dstend, -64]
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stp H_l, H_h, [dstend, -48]
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L(copy96):
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stp A_l, A_h, [dstin]
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stp B_l, B_h, [dstin, 16]
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stp E_l, E_h, [dstin, 32]
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stp F_l, F_h, [dstin, 48]
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stp C_l, C_h, [dstend, -32]
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stp D_l, D_h, [dstend, -16]
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ret
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.p2align 4
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/* Copy more than 128 bytes. */
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L(copy_long):
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/* Use backwards copy if there is an overlap. */
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sub tmp1, dstin, src
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cbz tmp1, L(copy0)
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cmp tmp1, count
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b.lo L(copy_long_backwards)
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/* Copy 16 bytes and then align dst to 16-byte alignment. */
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ldp D_l, D_h, [src]
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and tmp1, dstin, 15
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bic dst, dstin, 15
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sub src, src, tmp1
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add count, count, tmp1 /* Count is now 16 too large. */
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ldp A_l, A_h, [src, 16]
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stp D_l, D_h, [dstin]
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ldp B_l, B_h, [src, 32]
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ldp C_l, C_h, [src, 48]
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ldp D_l, D_h, [src, 64]!
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subs count, count, 128 + 16 /* Test and readjust count. */
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b.ls L(copy64_from_end)
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L(loop64):
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stp A_l, A_h, [dst, 16]
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ldp A_l, A_h, [src, 16]
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stp B_l, B_h, [dst, 32]
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ldp B_l, B_h, [src, 32]
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stp C_l, C_h, [dst, 48]
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ldp C_l, C_h, [src, 48]
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stp D_l, D_h, [dst, 64]!
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ldp D_l, D_h, [src, 64]!
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subs count, count, 64
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b.hi L(loop64)
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/* Write the last iteration and copy 64 bytes from the end. */
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L(copy64_from_end):
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ldp E_l, E_h, [srcend, -64]
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stp A_l, A_h, [dst, 16]
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ldp A_l, A_h, [srcend, -48]
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stp B_l, B_h, [dst, 32]
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ldp B_l, B_h, [srcend, -32]
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stp C_l, C_h, [dst, 48]
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ldp C_l, C_h, [srcend, -16]
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stp D_l, D_h, [dst, 64]
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stp E_l, E_h, [dstend, -64]
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stp A_l, A_h, [dstend, -48]
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stp B_l, B_h, [dstend, -32]
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stp C_l, C_h, [dstend, -16]
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ret
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.p2align 4
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/* Large backwards copy for overlapping copies.
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Copy 16 bytes and then align dst to 16-byte alignment. */
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L(copy_long_backwards):
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ldp D_l, D_h, [srcend, -16]
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and tmp1, dstend, 15
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sub srcend, srcend, tmp1
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sub count, count, tmp1
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ldp A_l, A_h, [srcend, -16]
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stp D_l, D_h, [dstend, -16]
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ldp B_l, B_h, [srcend, -32]
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ldp C_l, C_h, [srcend, -48]
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ldp D_l, D_h, [srcend, -64]!
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sub dstend, dstend, tmp1
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subs count, count, 128
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b.ls L(copy64_from_start)
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L(loop64_backwards):
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stp A_l, A_h, [dstend, -16]
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ldp A_l, A_h, [srcend, -16]
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stp B_l, B_h, [dstend, -32]
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ldp B_l, B_h, [srcend, -32]
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stp C_l, C_h, [dstend, -48]
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ldp C_l, C_h, [srcend, -48]
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stp D_l, D_h, [dstend, -64]!
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ldp D_l, D_h, [srcend, -64]!
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subs count, count, 64
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b.hi L(loop64_backwards)
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/* Write the last iteration and copy 64 bytes from the start. */
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L(copy64_from_start):
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ldp G_l, G_h, [src, 48]
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stp A_l, A_h, [dstend, -16]
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ldp A_l, A_h, [src, 32]
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stp B_l, B_h, [dstend, -32]
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ldp B_l, B_h, [src, 16]
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stp C_l, C_h, [dstend, -48]
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ldp C_l, C_h, [src]
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stp D_l, D_h, [dstend, -64]
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stp G_l, G_h, [dstin, 48]
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stp A_l, A_h, [dstin, 32]
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stp B_l, B_h, [dstin, 16]
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stp C_l, C_h, [dstin]
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ret
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END (memcpy)
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@ -2,10 +2,10 @@
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/*
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* Copyright (c) 2022, Ivaylo Ivanov <ivo.ivanov.ivanov1@gmail.com>
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*/
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.include "arch/aarch64/macros.h"
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#include "asmdefs.h"
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.section .text
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ENTRY _start
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ENTRY(_start)
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/* Set up the base address for the stack */
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adrp x0, _stack_end /* Load page of the _stack_end symbol */
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add x0, x0, #:lo12:_stack_end /* Add the offset within the page */
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@ -20,8 +20,8 @@ ENTRY _start
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add x1, x1, #:lo12:kernel /* Add offset within the page */
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bl main
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ENDPROC _start
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END(_start)
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ENTRY load_kernel
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ENTRY(load_kernel)
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br x4
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ENDPROC load_kernel
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END(load_kernel)
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@ -6,37 +6,54 @@
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#include "stdbool.h"
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#include "string.h"
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void *memcpy(void *s1, const void *s2, size_t n)
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void *memset (void *m, int c, size_t n)
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{
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char *dest = (char *)s1;
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const char *src = (const char *)s2;
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char *s = (char *) m;
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while (n--) {
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*dest++ = *src++;
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unsigned int i;
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unsigned long buffer;
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unsigned long *aligned_addr;
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unsigned int d = c & 0xff;
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while (UNALIGNED (s)) {
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if (n--)
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*s++ = (char) c;
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else
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return m;
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}
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return s1;
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}
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if (!TOO_SMALL (n)) {
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/* If we get this far, we know that n is large and s is word-aligned. */
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aligned_addr = (unsigned long *) s;
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void *memmove(void *s1, const void *s2, size_t n)
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{
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char *dest = (char *)s1;
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const char *src = (const char *)s2;
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/*
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* Store D into each char sized location in BUFFER so that
|
||||
* we can set large blocks quickly.
|
||||
*/
|
||||
buffer = (d << 8) | d;
|
||||
buffer |= (buffer << 16);
|
||||
for (i = 32; i < LBLOCKSIZE * 8; i <<= 1)
|
||||
buffer = (buffer << i) | buffer;
|
||||
|
||||
if (dest <= src) {
|
||||
while (n--) {
|
||||
*dest++ = *src++;
|
||||
/* Unroll the loop. */
|
||||
while (n >= LBLOCKSIZE*4) {
|
||||
*aligned_addr++ = buffer;
|
||||
*aligned_addr++ = buffer;
|
||||
*aligned_addr++ = buffer;
|
||||
*aligned_addr++ = buffer;
|
||||
n -= 4*LBLOCKSIZE;
|
||||
}
|
||||
} else {
|
||||
src += n;
|
||||
dest += n;
|
||||
|
||||
while (n--) {
|
||||
*--dest = *--src;
|
||||
while (n >= LBLOCKSIZE) {
|
||||
*aligned_addr++ = buffer;
|
||||
n -= LBLOCKSIZE;
|
||||
}
|
||||
|
||||
/* Pick up the remainder with a bytewise loop. */
|
||||
s = (char*)aligned_addr;
|
||||
}
|
||||
|
||||
return s1;
|
||||
return m;
|
||||
}
|
||||
|
||||
int memcmp(const void *s1, const void *s2, size_t n)
|
||||
@ -56,17 +73,6 @@ int memcmp(const void *s1, const void *s2, size_t n)
|
||||
return 0;
|
||||
}
|
||||
|
||||
void *memset(void *s, int c, size_t n)
|
||||
{
|
||||
unsigned char *p = (unsigned char *)s;
|
||||
|
||||
while (n--) {
|
||||
*p++ = (unsigned char)c;
|
||||
}
|
||||
|
||||
return s;
|
||||
}
|
||||
|
||||
void *memchr(const void *s, int c, size_t n)
|
||||
{
|
||||
const unsigned char *p = (const unsigned char *)s;
|
||||
|
||||
@ -8,23 +8,69 @@
|
||||
|
||||
#include "stddef.h"
|
||||
|
||||
void *memcpy(void *s1, const void *s2, size_t n);
|
||||
void *memmove(void *s1, const void *s2, size_t n);
|
||||
int memcmp(const void *s1, const void *s2, size_t n);
|
||||
void *memset(void *s, int c, size_t n);
|
||||
void *memchr(const void *s, int c, size_t n);
|
||||
char *strcpy(char *s1, const char *s2);
|
||||
char *strncpy(char *s1, const char *s2, size_t n);
|
||||
int strcmp(const char *s1, const char *s2);
|
||||
int strncmp(const char *s1, const char *s2, size_t n);
|
||||
size_t strlen(const char *s);
|
||||
size_t strnlen(const char *s, size_t n);
|
||||
char *strchr(const char *s, int c);
|
||||
char *strrchr(const char *s, int c);
|
||||
long atol(const char *s);
|
||||
void writel(unsigned int value, void* address);
|
||||
#define LBLOCKSIZE (sizeof(long))
|
||||
#define UNALIGNED(X) ((long)X & (LBLOCKSIZE - 1))
|
||||
#define TOO_SMALL(LEN) ((LEN) < LBLOCKSIZE)
|
||||
|
||||
static inline int tolower(int c)
|
||||
// C-driven unoptimized functions
|
||||
int memcmp (const void *s1, const void *s2, size_t n);
|
||||
void *memchr (const void *s, int c, size_t n);
|
||||
char *strcpy (char *s1, const char *s2);
|
||||
char *strncpy (char *s1, const char *s2, size_t n);
|
||||
int strcmp (const char *s1, const char *s2);
|
||||
int strncmp (const char *s1, const char *s2, size_t n);
|
||||
size_t strlen (const char *s);
|
||||
size_t strnlen (const char *s, size_t n);
|
||||
char *strchr (const char *s, int c);
|
||||
char *strrchr (const char *s, int c);
|
||||
long atol (const char *s);
|
||||
void writel (unsigned int value, void* address);
|
||||
|
||||
// C-driven optimized functions
|
||||
void *memset (void *m, int c, size_t n);
|
||||
|
||||
// Assembly-driven functions
|
||||
#ifdef __aarch64__
|
||||
void *memcpy (void *__restrict, const void *__restrict, size_t);
|
||||
void *memmove (void *, const void *, size_t);
|
||||
#endif
|
||||
|
||||
#ifdef __arm__
|
||||
void *memcpy (void *s1, const void *s2, size_t n)
|
||||
{
|
||||
char *dest = (char *)s1;
|
||||
const char *src = (const char *)s2;
|
||||
|
||||
while (n--) {
|
||||
*dest++ = *src++;
|
||||
}
|
||||
|
||||
return s1;
|
||||
}
|
||||
|
||||
void *memmove (void *s1, const void *s2, size_t n)
|
||||
{
|
||||
char *dest = (char *)s1;
|
||||
const char *src = (const char *)s2;
|
||||
|
||||
if (dest <= src) {
|
||||
while (n--) {
|
||||
*dest++ = *src++;
|
||||
}
|
||||
} else {
|
||||
src += n;
|
||||
dest += n;
|
||||
|
||||
while (n--) {
|
||||
*--dest = *--src;
|
||||
}
|
||||
}
|
||||
|
||||
return s1;
|
||||
}
|
||||
#endif
|
||||
|
||||
static inline int tolower (int c)
|
||||
{
|
||||
if (c >= 'A' && c <= 'Z')
|
||||
return c - 'A' + 'a';
|
||||
@ -32,7 +78,7 @@ static inline int tolower(int c)
|
||||
return c;
|
||||
}
|
||||
|
||||
static inline int toupper(int c)
|
||||
static inline int toupper (int c)
|
||||
{
|
||||
if (c >= 'a' && c <= 'z')
|
||||
return c - 'a' + 'A';
|
||||
|
||||
Loading…
Reference in New Issue
Block a user