a37f660599
This adds ARM support to BaseMemoryLibOptDxe, partially based on the cortex-strings library (ScanMem) and the existing CopyMem() implementation from BaseMemoryLibStm in ArmPkg. All string routines are accelerated except ScanMem16, ScanMem32, ScanMem64 and IsZeroBuffer, which can wait for another day. (Very few occurrences exist in the codebase) Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Liming Gao <liming.gao@intel.com>
148 lines
3.7 KiB
NASM
148 lines
3.7 KiB
NASM
;------------------------------------------------------------------------------
|
|
;
|
|
; CopyMem() worker for ARM
|
|
;
|
|
; This file started out as C code that did 64 bit moves if the buffer was
|
|
; 32-bit aligned, else it does a byte copy. It also does a byte copy for
|
|
; any trailing bytes. It was updated to do 32-byte copies using stm/ldm.
|
|
;
|
|
; Copyright (c) 2008 - 2010, Apple Inc. All rights reserved.<BR>
|
|
; Copyright (c) 2016, Linaro Ltd. All rights reserved.<BR>
|
|
; This program and the accompanying materials
|
|
; are licensed and made available under the terms and conditions of the BSD License
|
|
; which accompanies this distribution. The full text of the license may be found at
|
|
; http://opensource.org/licenses/bsd-license.php
|
|
;
|
|
; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
|
|
; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
|
|
;
|
|
;------------------------------------------------------------------------------
|
|
|
|
EXPORT InternalMemCopyMem
|
|
AREA SetMem, CODE, READONLY
|
|
THUMB
|
|
|
|
InternalMemCopyMem
|
|
stmfd sp!, {r4-r11, lr}
|
|
// Save the input parameters in extra registers (r11 = destination, r14 = source, r12 = length)
|
|
mov r11, r0
|
|
mov r10, r0
|
|
mov r12, r2
|
|
mov r14, r1
|
|
|
|
memcopy_check_overlapped
|
|
cmp r11, r1
|
|
// If (dest < source)
|
|
bcc memcopy_check_optim_default
|
|
|
|
// If (source + length < dest)
|
|
rsb r3, r1, r11
|
|
cmp r12, r3
|
|
bcc memcopy_check_optim_default
|
|
b memcopy_check_optim_overlap
|
|
|
|
memcopy_check_optim_default
|
|
// Check if we can use an optimized path ((length >= 32) && destination word-aligned && source word-aligned) for the memcopy (optimized path if r0 == 1)
|
|
tst r0, #0xF
|
|
movne r0, #0
|
|
bne memcopy_default
|
|
tst r1, #0xF
|
|
movne r3, #0
|
|
moveq r3, #1
|
|
cmp r2, #31
|
|
movls r0, #0
|
|
andhi r0, r3, #1
|
|
b memcopy_default
|
|
|
|
memcopy_check_optim_overlap
|
|
// r10 = dest_end, r14 = source_end
|
|
add r10, r11, r12
|
|
add r14, r12, r1
|
|
|
|
// Are we in the optimized case ((length >= 32) && dest_end word-aligned && source_end word-aligned)
|
|
cmp r2, #31
|
|
movls r0, #0
|
|
movhi r0, #1
|
|
tst r10, #0xF
|
|
movne r0, #0
|
|
tst r14, #0xF
|
|
movne r0, #0
|
|
b memcopy_overlapped
|
|
|
|
memcopy_overlapped_non_optim
|
|
// We read 1 byte from the end of the source buffer
|
|
sub r3, r14, #1
|
|
sub r12, r12, #1
|
|
ldrb r3, [r3, #0]
|
|
sub r2, r10, #1
|
|
cmp r12, #0
|
|
// We write 1 byte at the end of the dest buffer
|
|
sub r10, r10, #1
|
|
sub r14, r14, #1
|
|
strb r3, [r2, #0]
|
|
bne memcopy_overlapped_non_optim
|
|
b memcopy_end
|
|
|
|
// r10 = dest_end, r14 = source_end
|
|
memcopy_overlapped
|
|
// Are we in the optimized case ?
|
|
cmp r0, #0
|
|
beq memcopy_overlapped_non_optim
|
|
|
|
// Optimized Overlapped - Read 32 bytes
|
|
sub r14, r14, #32
|
|
sub r12, r12, #32
|
|
cmp r12, #31
|
|
ldmia r14, {r2-r9}
|
|
|
|
// If length is less than 32 then disable optim
|
|
movls r0, #0
|
|
|
|
cmp r12, #0
|
|
|
|
// Optimized Overlapped - Write 32 bytes
|
|
sub r10, r10, #32
|
|
stmia r10, {r2-r9}
|
|
|
|
// while (length != 0)
|
|
bne memcopy_overlapped
|
|
b memcopy_end
|
|
|
|
memcopy_default_non_optim
|
|
// Byte copy
|
|
ldrb r3, [r14], #1
|
|
sub r12, r12, #1
|
|
strb r3, [r10], #1
|
|
|
|
memcopy_default
|
|
cmp r12, #0
|
|
beq memcopy_end
|
|
|
|
// r10 = dest, r14 = source
|
|
memcopy_default_loop
|
|
cmp r0, #0
|
|
beq memcopy_default_non_optim
|
|
|
|
// Optimized memcopy - Read 32 Bytes
|
|
sub r12, r12, #32
|
|
cmp r12, #31
|
|
ldmia r14!, {r2-r9}
|
|
|
|
// If length is less than 32 then disable optim
|
|
movls r0, #0
|
|
|
|
cmp r12, #0
|
|
|
|
// Optimized memcopy - Write 32 Bytes
|
|
stmia r10!, {r2-r9}
|
|
|
|
// while (length != 0)
|
|
bne memcopy_default_loop
|
|
|
|
memcopy_end
|
|
mov r0, r11
|
|
ldmfd sp!, {r4-r11, pc}
|
|
|
|
END
|
|
|