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Diffstat (limited to 'arch/metag/lib/memcpy.S')
| -rw-r--r-- | arch/metag/lib/memcpy.S | 186 |
1 files changed, 0 insertions, 186 deletions
diff --git a/arch/metag/lib/memcpy.S b/arch/metag/lib/memcpy.S deleted file mode 100644 index c2e8395..0000000 --- a/arch/metag/lib/memcpy.S +++ /dev/null @@ -1,186 +0,0 @@ -! SPDX-License-Identifier: GPL-2.0 -! Copyright (C) 2008-2012 Imagination Technologies Ltd. - - .text - .global _memcpy - .type _memcpy,function -! D1Ar1 dst -! D0Ar2 src -! D1Ar3 cnt -! D0Re0 dst -_memcpy: - CMP D1Ar3, #16 - MOV A1.2, D0Ar2 ! source pointer - MOV A0.2, D1Ar1 ! destination pointer - MOV A0.3, D1Ar1 ! for return value -! If there are less than 16 bytes to copy use the byte copy loop - BGE $Llong_copy - -$Lbyte_copy: -! Simply copy a byte at a time - SUBS TXRPT, D1Ar3, #1 - BLT $Lend -$Lloop_byte: - GETB D1Re0, [A1.2++] - SETB [A0.2++], D1Re0 - BR $Lloop_byte - -$Lend: -! Finally set return value and return - MOV D0Re0, A0.3 - MOV PC, D1RtP - -$Llong_copy: - ANDS D1Ar5, D1Ar1, #7 ! test destination alignment - BZ $Laligned_dst - -! The destination address is not 8 byte aligned. We will copy bytes from -! the source to the destination until the remaining data has an 8 byte -! destination address alignment (i.e we should never copy more than 7 -! bytes here). -$Lalign_dst: - GETB D0Re0, [A1.2++] - ADD D1Ar5, D1Ar5, #1 ! dest is aligned when D1Ar5 reaches #8 - SUB D1Ar3, D1Ar3, #1 ! decrement count of remaining bytes - SETB [A0.2++], D0Re0 - CMP D1Ar5, #8 - BNE $Lalign_dst - -! We have at least (16 - 7) = 9 bytes to copy - calculate the number of 8 byte -! blocks, then jump to the unaligned copy loop or fall through to the aligned -! copy loop as appropriate. -$Laligned_dst: - MOV D0Ar4, A1.2 - LSR D1Ar5, D1Ar3, #3 ! D1Ar5 = number of 8 byte blocks - ANDS D0Ar4, D0Ar4, #7 ! test source alignment - BNZ $Lunaligned_copy ! if unaligned, use unaligned copy loop - -! Both source and destination are 8 byte aligned - the easy case. -$Laligned_copy: - LSRS D1Ar5, D1Ar3, #5 ! D1Ar5 = number of 32 byte blocks - BZ $Lbyte_copy - SUB TXRPT, D1Ar5, #1 - -$Laligned_32: - GETL D0Re0, D1Re0, [A1.2++] - GETL D0Ar6, D1Ar5, [A1.2++] - SETL [A0.2++], D0Re0, D1Re0 - SETL [A0.2++], D0Ar6, D1Ar5 - GETL D0Re0, D1Re0, [A1.2++] - GETL D0Ar6, D1Ar5, [A1.2++] - SETL [A0.2++], D0Re0, D1Re0 - SETL [A0.2++], D0Ar6, D1Ar5 - BR $Laligned_32 - -! If there are any remaining bytes use the byte copy loop, otherwise we are done - ANDS D1Ar3, D1Ar3, #0x1f - BNZ $Lbyte_copy - B $Lend - -! The destination is 8 byte aligned but the source is not, and there are 8 -! or more bytes to be copied. -$Lunaligned_copy: -! Adjust the source pointer (A1.2) to the 8 byte boundary before its -! current value - MOV D0Ar4, A1.2 - MOV D0Ar6, A1.2 - ANDMB D0Ar4, D0Ar4, #0xfff8 - MOV A1.2, D0Ar4 -! Save the number of bytes of mis-alignment in D0Ar4 for use later - SUBS D0Ar6, D0Ar6, D0Ar4 - MOV D0Ar4, D0Ar6 -! if there is no mis-alignment after all, use the aligned copy loop - BZ $Laligned_copy - -! prefetch 8 bytes - GETL D0Re0, D1Re0, [A1.2] - - SUB TXRPT, D1Ar5, #1 - -! There are 3 mis-alignment cases to be considered. Less than 4 bytes, exactly -! 4 bytes, and more than 4 bytes. - CMP D0Ar6, #4 - BLT $Lunaligned_1_2_3 ! use 1-3 byte mis-alignment loop - BZ $Lunaligned_4 ! use 4 byte mis-alignment loop - -! The mis-alignment is more than 4 bytes -$Lunaligned_5_6_7: - SUB D0Ar6, D0Ar6, #4 -! Calculate the bit offsets required for the shift operations necesssary -! to align the data. -! D0Ar6 = bit offset, D1Ar5 = (32 - bit offset) - MULW D0Ar6, D0Ar6, #8 - MOV D1Ar5, #32 - SUB D1Ar5, D1Ar5, D0Ar6 -! Move data 4 bytes before we enter the main loop - MOV D0Re0, D1Re0 - -$Lloop_5_6_7: - GETL D0Ar2, D1Ar1, [++A1.2] -! form 64-bit data in D0Re0, D1Re0 - LSR D0Re0, D0Re0, D0Ar6 - MOV D1Re0, D0Ar2 - LSL D1Re0, D1Re0, D1Ar5 - ADD D0Re0, D0Re0, D1Re0 - - LSR D0Ar2, D0Ar2, D0Ar6 - LSL D1Re0, D1Ar1, D1Ar5 - ADD D1Re0, D1Re0, D0Ar2 - - SETL [A0.2++], D0Re0, D1Re0 - MOV D0Re0, D1Ar1 - BR $Lloop_5_6_7 - - B $Lunaligned_end - -$Lunaligned_1_2_3: -! Calculate the bit offsets required for the shift operations necesssary -! to align the data. -! D0Ar6 = bit offset, D1Ar5 = (32 - bit offset) - MULW D0Ar6, D0Ar6, #8 - MOV D1Ar5, #32 - SUB D1Ar5, D1Ar5, D0Ar6 - -$Lloop_1_2_3: -! form 64-bit data in D0Re0,D1Re0 - LSR D0Re0, D0Re0, D0Ar6 - LSL D1Ar1, D1Re0, D1Ar5 - ADD D0Re0, D0Re0, D1Ar1 - MOV D0Ar2, D1Re0 - LSR D0FrT, D0Ar2, D0Ar6 - GETL D0Ar2, D1Ar1, [++A1.2] - - MOV D1Re0, D0Ar2 - LSL D1Re0, D1Re0, D1Ar5 - ADD D1Re0, D1Re0, D0FrT - - SETL [A0.2++], D0Re0, D1Re0 - MOV D0Re0, D0Ar2 - MOV D1Re0, D1Ar1 - BR $Lloop_1_2_3 - - B $Lunaligned_end - -! The 4 byte mis-alignment case - this does not require any shifting, just a -! shuffling of registers. -$Lunaligned_4: - MOV D0Re0, D1Re0 -$Lloop_4: - GETL D0Ar2, D1Ar1, [++A1.2] - MOV D1Re0, D0Ar2 - SETL [A0.2++], D0Re0, D1Re0 - MOV D0Re0, D1Ar1 - BR $Lloop_4 - -$Lunaligned_end: -! If there are no remaining bytes to copy, we are done. - ANDS D1Ar3, D1Ar3, #7 - BZ $Lend -! Re-adjust the source pointer (A1.2) back to the actual (unaligned) byte -! address of the remaining bytes, and fall through to the byte copy loop. - MOV D0Ar6, A1.2 - ADD D1Ar5, D0Ar4, D0Ar6 - MOV A1.2, D1Ar5 - B $Lbyte_copy - - .size _memcpy,.-_memcpy |
