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Diffstat (limited to 'sysdeps/tile/tilepro/memcpy.S')
| -rw-r--r-- | sysdeps/tile/tilepro/memcpy.S | 397 |
1 files changed, 0 insertions, 397 deletions
diff --git a/sysdeps/tile/tilepro/memcpy.S b/sysdeps/tile/tilepro/memcpy.S deleted file mode 100644 index a6bdfbdcff..0000000000 --- a/sysdeps/tile/tilepro/memcpy.S +++ /dev/null @@ -1,397 +0,0 @@ -/* Copyright (C) 2011-2016 Free Software Foundation, Inc. - This file is part of the GNU C Library. - Contributed by Chris Metcalf <cmetcalf@tilera.com>, 2011. - - The GNU C Library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public - License as published by the Free Software Foundation; either - version 2.1 of the License, or (at your option) any later version. - - The GNU C Library is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public - License along with the GNU C Library. If not, see - <http://www.gnu.org/licenses/>. */ - -#include <arch/chip.h> -#include <sysdep.h> - - .text -ENTRY (__memcpy) - FEEDBACK_ENTER(__memcpy) - - /* r0 is the dest, r1 is the source, r2 is the size. */ - - /* Save aside original dest so we can return it at the end. */ - { sw sp, lr; move r23, r0; or r4, r0, r1 } - cfi_offset (lr, 0) - - /* Check for an empty size. */ - { bz r2, .Ldone; andi r4, r4, 3 } - - /* Check for an unaligned source or dest. */ - { bnz r4, .Lcopy_unaligned_maybe_many; addli r4, r2, -256 } - -.Lcheck_aligned_copy_size: - /* If we are copying < 256 bytes, branch to simple case. */ - { blzt r4, .Lcopy_8_check; slti_u r8, r2, 8 } - - /* Copying >= 256 bytes, so jump to complex prefetching loop. */ - { andi r6, r1, 63; j .Lcopy_many } - -/* Aligned 4 byte at a time copy loop. */ - -.Lcopy_8_loop: - /* Copy two words at a time to hide load latency. */ - { lw r3, r1; addi r1, r1, 4; slti_u r8, r2, 16 } - { lw r4, r1; addi r1, r1, 4 } - { sw r0, r3; addi r0, r0, 4; addi r2, r2, -4 } - { sw r0, r4; addi r0, r0, 4; addi r2, r2, -4 } -.Lcopy_8_check: - { bzt r8, .Lcopy_8_loop; slti_u r4, r2, 4 } - - /* Copy odd leftover word, if any. */ - { bnzt r4, .Lcheck_odd_stragglers } - { lw r3, r1; addi r1, r1, 4 } - { sw r0, r3; addi r0, r0, 4; addi r2, r2, -4 } - -.Lcheck_odd_stragglers: - { bnz r2, .Lcopy_unaligned_few } - -.Ldone: - { move r0, r23; jrp lr } - -/* Prefetching multiple cache line copy handler (for large transfers). */ - - /* Copy words until r1 is cache-line-aligned. */ -.Lalign_loop: - { lw r3, r1; addi r1, r1, 4 } - { andi r6, r1, 63 } - { sw r0, r3; addi r0, r0, 4; addi r2, r2, -4 } -.Lcopy_many: - { bnzt r6, .Lalign_loop; addi r9, r0, 63 } - - { addi r3, r1, 60; andi r9, r9, -64 } - - /* No need to prefetch dst, we'll just do the wh64 - right before we copy a line. */ - { lw r5, r3; addi r3, r3, 64; movei r4, 1 } - /* Intentionally stall for a few cycles to leave L2 cache alone. */ - { bnzt zero, .; move r27, lr } - { lw r6, r3; addi r3, r3, 64 } - /* Intentionally stall for a few cycles to leave L2 cache alone. */ - { bnzt zero, . } - { lw r7, r3; addi r3, r3, 64 } - /* Intentionally stall for a few cycles to leave L2 cache alone. */ - { bz zero, .Lbig_loop2 } - - /* On entry to this loop: - - r0 points to the start of dst line 0 - - r1 points to start of src line 0 - - r2 >= (256 - 60), only the first time the loop trips. - - r3 contains r1 + 128 + 60 [pointer to end of source line 2] - This is our prefetch address. When we get near the end - rather than prefetching off the end this is changed to point - to some "safe" recently loaded address. - - r5 contains *(r1 + 60) [i.e. last word of source line 0] - - r6 contains *(r1 + 64 + 60) [i.e. last word of source line 1] - - r9 contains ((r0 + 63) & -64) - [start of next dst cache line.] */ - -.Lbig_loop: - { jal .Lcopy_line2; add r15, r1, r2 } - -.Lbig_loop2: - /* Copy line 0, first stalling until r5 is ready. */ - { move r12, r5; lw r16, r1 } - { bz r4, .Lcopy_8_check; slti_u r8, r2, 8 } - /* Prefetch several lines ahead. */ - { lw r5, r3; addi r3, r3, 64 } - { jal .Lcopy_line } - - /* Copy line 1, first stalling until r6 is ready. */ - { move r12, r6; lw r16, r1 } - { bz r4, .Lcopy_8_check; slti_u r8, r2, 8 } - /* Prefetch several lines ahead. */ - { lw r6, r3; addi r3, r3, 64 } - { jal .Lcopy_line } - - /* Copy line 2, first stalling until r7 is ready. */ - { move r12, r7; lw r16, r1 } - { bz r4, .Lcopy_8_check; slti_u r8, r2, 8 } - /* Prefetch several lines ahead. */ - { lw r7, r3; addi r3, r3, 64 } - /* Use up a caches-busy cycle by jumping back to the top of the - loop. Might as well get it out of the way now. */ - { j .Lbig_loop } - - - /* On entry: - - r0 points to the destination line. - - r1 points to the source line. - - r3 is the next prefetch address. - - r9 holds the last address used for wh64. - - r12 = WORD_15 - - r16 = WORD_0. - - r17 == r1 + 16. - - r27 holds saved lr to restore. - - On exit: - - r0 is incremented by 64. - - r1 is incremented by 64, unless that would point to a word - beyond the end of the source array, in which case it is redirected - to point to an arbitrary word already in the cache. - - r2 is decremented by 64. - - r3 is unchanged, unless it points to a word beyond the - end of the source array, in which case it is redirected - to point to an arbitrary word already in the cache. - Redirecting is OK since if we are that close to the end - of the array we will not come back to this subroutine - and use the contents of the prefetched address. - - r4 is nonzero iff r2 >= 64. - - r9 is incremented by 64, unless it points beyond the - end of the last full destination cache line, in which - case it is redirected to a "safe address" that can be - clobbered (sp - 64) - - lr contains the value in r27. */ - -/* r26 unused */ - -.Lcopy_line: - /* TODO: when r3 goes past the end, we would like to redirect it - to prefetch the last partial cache line (if any) just once, for the - benefit of the final cleanup loop. But we don't want to - prefetch that line more than once, or subsequent prefetches - will go into the RTF. But then .Lbig_loop should unconditionally - branch to top of loop to execute final prefetch, and its - nop should become a conditional branch. */ - - /* We need two non-memory cycles here to cover the resources - used by the loads initiated by the caller. */ - { add r15, r1, r2 } -.Lcopy_line2: - { slt_u r13, r3, r15; addi r17, r1, 16 } - - /* NOTE: this will stall for one cycle as L1 is busy. */ - - /* Fill second L1D line. */ - { lw r17, r17; addi r1, r1, 48; mvz r3, r13, r1 } /* r17 = WORD_4 */ - - /* Prepare destination line for writing. */ - { wh64 r9; addi r9, r9, 64 } - - /* Load seven words that are L1D hits to cover wh64 L2 usage. */ - - /* Load the three remaining words from the last L1D line, which - we know has already filled the L1D. */ - { lw r4, r1; addi r1, r1, 4; addi r20, r1, 16 } /* r4 = WORD_12 */ - { lw r8, r1; addi r1, r1, 4; slt_u r13, r20, r15 }/* r8 = WORD_13 */ - { lw r11, r1; addi r1, r1, -52; mvz r20, r13, r1 } /* r11 = WORD_14 */ - - /* Load the three remaining words from the first L1D line, first - stalling until it has filled by "looking at" r16. */ - { lw r13, r1; addi r1, r1, 4; move zero, r16 } /* r13 = WORD_1 */ - { lw r14, r1; addi r1, r1, 4 } /* r14 = WORD_2 */ - { lw r15, r1; addi r1, r1, 8; addi r10, r0, 60 } /* r15 = WORD_3 */ - - /* Load second word from the second L1D line, first - stalling until it has filled by "looking at" r17. */ - { lw r19, r1; addi r1, r1, 4; move zero, r17 } /* r19 = WORD_5 */ - - /* Store last word to the destination line, potentially dirtying it - for the first time, which keeps the L2 busy for two cycles. */ - { sw r10, r12 } /* store(WORD_15) */ - - /* Use two L1D hits to cover the sw L2 access above. */ - { lw r10, r1; addi r1, r1, 4 } /* r10 = WORD_6 */ - { lw r12, r1; addi r1, r1, 4 } /* r12 = WORD_7 */ - - /* Fill third L1D line. */ - { lw r18, r1; addi r1, r1, 4 } /* r18 = WORD_8 */ - - /* Store first L1D line. */ - { sw r0, r16; addi r0, r0, 4; add r16, r0, r2 } /* store(WORD_0) */ - { sw r0, r13; addi r0, r0, 4; andi r16, r16, -64 } /* store(WORD_1) */ - { sw r0, r14; addi r0, r0, 4; slt_u r16, r9, r16 } /* store(WORD_2) */ - { sw r0, r15; addi r0, r0, 4; addi r13, sp, -64 } /* store(WORD_3) */ - - /* Store second L1D line. */ - { sw r0, r17; addi r0, r0, 4; mvz r9, r16, r13 }/* store(WORD_4) */ - { sw r0, r19; addi r0, r0, 4 } /* store(WORD_5) */ - { sw r0, r10; addi r0, r0, 4 } /* store(WORD_6) */ - { sw r0, r12; addi r0, r0, 4 } /* store(WORD_7) */ - - { lw r13, r1; addi r1, r1, 4; move zero, r18 } /* r13 = WORD_9 */ - { lw r14, r1; addi r1, r1, 4 } /* r14 = WORD_10 */ - { lw r15, r1; move r1, r20 } /* r15 = WORD_11 */ - - /* Store third L1D line. */ - { sw r0, r18; addi r0, r0, 4 } /* store(WORD_8) */ - { sw r0, r13; addi r0, r0, 4 } /* store(WORD_9) */ - { sw r0, r14; addi r0, r0, 4 } /* store(WORD_10) */ - { sw r0, r15; addi r0, r0, 4 } /* store(WORD_11) */ - - /* Store rest of fourth L1D line. */ - { sw r0, r4; addi r0, r0, 4 } /* store(WORD_12) */ - { - sw r0, r8 /* store(WORD_13) */ - addi r0, r0, 4 - /* Will r2 be > 64 after we subtract 64 below? */ - shri r4, r2, 7 - } - { - sw r0, r11 /* store(WORD_14) */ - addi r0, r0, 8 - /* Record 64 bytes successfully copied. */ - addi r2, r2, -64 - } - - { jrp lr; move lr, r27 } - - /* Convey to the backtrace library that the stack frame is - size zero, and the real return address is on the stack - rather than in 'lr'. */ - { info 8 } - - .align 64 -.Lcopy_unaligned_maybe_many: - /* Skip the setup overhead if we aren't copying many bytes. */ - { slti_u r8, r2, 20; sub r4, zero, r0 } - { bnzt r8, .Lcopy_unaligned_few; andi r4, r4, 3 } - { bz r4, .Ldest_is_word_aligned; add r18, r1, r2 } - -/* Unaligned 4 byte at a time copy handler. */ - - /* Copy single bytes until r0 == 0 mod 4, so we can store words. */ -.Lalign_dest_loop: - { lb_u r3, r1; addi r1, r1, 1; addi r4, r4, -1 } - { sb r0, r3; addi r0, r0, 1; addi r2, r2, -1 } - { bnzt r4, .Lalign_dest_loop; andi r3, r1, 3 } - - /* If source and dest are now *both* aligned, do an aligned copy. */ - { bz r3, .Lcheck_aligned_copy_size; addli r4, r2, -256 } - -.Ldest_is_word_aligned: - - { andi r8, r0, 63; lwadd_na r6, r1, 4} - { slti_u r9, r2, 64; bz r8, .Ldest_is_L2_line_aligned } - - /* This copies unaligned words until either there are fewer - than 4 bytes left to copy, or until the destination pointer - is cache-aligned, whichever comes first. - - On entry: - - r0 is the next store address. - - r1 points 4 bytes past the load address corresponding to r0. - - r2 >= 4 - - r6 is the next aligned word loaded. */ -.Lcopy_unaligned_src_words: - { lwadd_na r7, r1, 4; slti_u r8, r2, 4 + 4 } - /* stall */ - { dword_align r6, r7, r1; slti_u r9, r2, 64 + 4 } - { swadd r0, r6, 4; addi r2, r2, -4 } - { bnz r8, .Lcleanup_unaligned_words; andi r8, r0, 63 } - { bnzt r8, .Lcopy_unaligned_src_words; move r6, r7 } - - /* On entry: - - r0 is the next store address. - - r1 points 4 bytes past the load address corresponding to r0. - - r2 >= 4 (# of bytes left to store). - - r6 is the next aligned src word value. - - r9 = (r2 < 64U). - - r18 points one byte past the end of source memory. */ -.Ldest_is_L2_line_aligned: - - { - /* Not a full cache line remains. */ - bnz r9, .Lcleanup_unaligned_words - move r7, r6 - } - - /* r2 >= 64 */ - - /* Kick off two prefetches, but don't go past the end. */ - { addi r3, r1, 63 - 4; addi r8, r1, 64 + 63 - 4 } - { prefetch r3; move r3, r8; slt_u r8, r8, r18 } - { mvz r3, r8, r1; addi r8, r3, 64 } - { prefetch r3; move r3, r8; slt_u r8, r8, r18 } - { mvz r3, r8, r1; movei r17, 0 } - -.Lcopy_unaligned_line: - /* Prefetch another line. */ - { prefetch r3; addi r15, r1, 60; addi r3, r3, 64 } - /* Fire off a load of the last word we are about to copy. */ - { lw_na r15, r15; slt_u r8, r3, r18 } - - { mvz r3, r8, r1; wh64 r0 } - - /* This loop runs twice. - - On entry: - - r17 is even before the first iteration, and odd before - the second. It is incremented inside the loop. Encountering - an even value at the end of the loop makes it stop. */ -.Lcopy_half_an_unaligned_line: - { - /* Stall until the last byte is ready. In the steady state this - guarantees all words to load below will be in the L2 cache, which - avoids shunting the loads to the RTF. */ - move zero, r15 - lwadd_na r7, r1, 16 - } - { lwadd_na r11, r1, 12 } - { lwadd_na r14, r1, -24 } - { lwadd_na r8, r1, 4 } - { lwadd_na r9, r1, 4 } - { - lwadd_na r10, r1, 8 - /* r16 = (r2 < 64), after we subtract 32 from r2 below. */ - slti_u r16, r2, 64 + 32 - } - { lwadd_na r12, r1, 4; addi r17, r17, 1 } - { lwadd_na r13, r1, 8; dword_align r6, r7, r1 } - { swadd r0, r6, 4; dword_align r7, r8, r1 } - { swadd r0, r7, 4; dword_align r8, r9, r1 } - { swadd r0, r8, 4; dword_align r9, r10, r1 } - { swadd r0, r9, 4; dword_align r10, r11, r1 } - { swadd r0, r10, 4; dword_align r11, r12, r1 } - { swadd r0, r11, 4; dword_align r12, r13, r1 } - { swadd r0, r12, 4; dword_align r13, r14, r1 } - { swadd r0, r13, 4; addi r2, r2, -32 } - { move r6, r14; bbst r17, .Lcopy_half_an_unaligned_line } - - { bzt r16, .Lcopy_unaligned_line; move r7, r6 } - - /* On entry: - - r0 is the next store address. - - r1 points 4 bytes past the load address corresponding to r0. - - r2 >= 0 (# of bytes left to store). - - r7 is the next aligned src word value. */ -.Lcleanup_unaligned_words: - /* Handle any trailing bytes. */ - { bz r2, .Lcopy_unaligned_done; slti_u r8, r2, 4 } - { bzt r8, .Lcopy_unaligned_src_words; move r6, r7 } - - /* Move r1 back to the point where it corresponds to r0. */ - { addi r1, r1, -4 } - - /* Fall through */ - -/* 1 byte at a time copy handler. */ - -.Lcopy_unaligned_few: - { lb_u r3, r1; addi r1, r1, 1 } - { sb r0, r3; addi r0, r0, 1; addi r2, r2, -1 } - { bnzt r2, .Lcopy_unaligned_few } - -.Lcopy_unaligned_done: - - { move r0, r23; jrp lr } - -END (__memcpy) - -weak_alias (__memcpy, memcpy) -libc_hidden_builtin_def (memcpy) |