From af1a266670d040d2f4083ff309d732d648afba2a Mon Sep 17 00:00:00 2001 From: Angelos Mouzakitis Date: Tue, 10 Oct 2023 14:33:42 +0000 Subject: Add submodule dependency files Change-Id: Iaf8d18082d3991dec7c0ebbea540f092188eb4ec --- .../Library/BaseMemoryLibOptDxe/Arm/CopyMem.S | 170 +++++++++++++++++++++ 1 file changed, 170 insertions(+) create mode 100644 roms/edk2/MdePkg/Library/BaseMemoryLibOptDxe/Arm/CopyMem.S (limited to 'roms/edk2/MdePkg/Library/BaseMemoryLibOptDxe/Arm/CopyMem.S') diff --git a/roms/edk2/MdePkg/Library/BaseMemoryLibOptDxe/Arm/CopyMem.S b/roms/edk2/MdePkg/Library/BaseMemoryLibOptDxe/Arm/CopyMem.S new file mode 100644 index 000000000..c36af196a --- /dev/null +++ b/roms/edk2/MdePkg/Library/BaseMemoryLibOptDxe/Arm/CopyMem.S @@ -0,0 +1,170 @@ +#------------------------------------------------------------------------------ +# +# 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.
+# Copyright (c) 2016, Linaro Ltd. All rights reserved.
+# SPDX-License-Identifier: BSD-2-Clause-Patent +# +#------------------------------------------------------------------------------ + + .text + .thumb + .syntax unified + +/** + Copy Length bytes from Source to Destination. Overlap is OK. + + This implementation + + @param Destination Target of copy + @param Source Place to copy from + @param Length Number of bytes to copy + + @return Destination + + +VOID * +EFIAPI +InternalMemCopyMem ( + OUT VOID *DestinationBuffer, + IN CONST VOID *SourceBuffer, + IN UINTN Length + ) +**/ + .type ASM_PFX(InternalMemCopyMem), %function +ASM_GLOBAL ASM_PFX(InternalMemCopyMem) +ASM_PFX(InternalMemCopyMem): + push {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 + + 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 + it ne + movne.n r0, #0 + bne memcopy_default + tst r1, #0xF + it ne + movne.n r3, #0 + it eq + moveq.n r3, #1 + cmp r2, #31 + it ls + movls.n r0, #0 + bls memcopy_default + and 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 + it ls + movls.n r0, #0 + it hi + movhi.n r0, #1 + tst r10, #0xF + it ne + movne.n r0, #0 + tst r14, #0xF + it ne + movne.n 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 + it ls + movls.n 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 + it ls + movls.n 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 + pop {r4-r11, pc} -- cgit 1.2.3-korg