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88b57b8ed4
Implement x86-64 memmove with unaligned load/store and rep movsb. Support 16-byte, 32-byte and 64-byte vector register sizes. When size <= 8 times of vector register size, there is no check for address overlap bewteen source and destination. Since overhead for overlap check is small when size > 8 times of vector register size, memcpy is an alias of memmove. A single file provides 2 implementations of memmove, one with rep movsb and the other without rep movsb. They share the same codes when size is between 2 times of vector register size and REP_MOVSB_THRESHOLD which is 2KB for 16-byte vector register size and scaled up by large vector register size. Key features: 1. Use overlapping load and store to avoid branch. 2. For size <= 8 times of vector register size, load all sources into registers and store them together. 3. If there is no address overlap bewteen source and destination, copy from both ends with 4 times of vector register size at a time. 4. If address of destination > address of source, backward copy 8 times of vector register size at a time. 5. Otherwise, forward copy 8 times of vector register size at a time. 6. Use rep movsb only for forward copy. Avoid slow backward rep movsb by fallbacking to backward copy 8 times of vector register size at a time. 7. Skip when address of destination == address of source. [BZ #19776] * sysdeps/x86_64/multiarch/Makefile (sysdep_routines): Add memmove-sse2-unaligned-erms, memmove-avx-unaligned-erms and memmove-avx512-unaligned-erms. * sysdeps/x86_64/multiarch/ifunc-impl-list.c (__libc_ifunc_impl_list): Test __memmove_chk_avx512_unaligned_2, __memmove_chk_avx512_unaligned_erms, __memmove_chk_avx_unaligned_2, __memmove_chk_avx_unaligned_erms, __memmove_chk_sse2_unaligned_2, __memmove_chk_sse2_unaligned_erms, __memmove_avx_unaligned_2, __memmove_avx_unaligned_erms, __memmove_avx512_unaligned_2, __memmove_avx512_unaligned_erms, __memmove_erms, __memmove_sse2_unaligned_2, __memmove_sse2_unaligned_erms, __memcpy_chk_avx512_unaligned_2, __memcpy_chk_avx512_unaligned_erms, __memcpy_chk_avx_unaligned_2, __memcpy_chk_avx_unaligned_erms, __memcpy_chk_sse2_unaligned_2, __memcpy_chk_sse2_unaligned_erms, __memcpy_avx_unaligned_2, __memcpy_avx_unaligned_erms, __memcpy_avx512_unaligned_2, __memcpy_avx512_unaligned_erms, __memcpy_sse2_unaligned_2, __memcpy_sse2_unaligned_erms, __memcpy_erms, __mempcpy_chk_avx512_unaligned_2, __mempcpy_chk_avx512_unaligned_erms, __mempcpy_chk_avx_unaligned_2, __mempcpy_chk_avx_unaligned_erms, __mempcpy_chk_sse2_unaligned_2, __mempcpy_chk_sse2_unaligned_erms, __mempcpy_avx512_unaligned_2, __mempcpy_avx512_unaligned_erms, __mempcpy_avx_unaligned_2, __mempcpy_avx_unaligned_erms, __mempcpy_sse2_unaligned_2, __mempcpy_sse2_unaligned_erms and __mempcpy_erms. * sysdeps/x86_64/multiarch/memmove-avx-unaligned-erms.S: New file. * sysdeps/x86_64/multiarch/memmove-avx512-unaligned-erms.S: Likwise. * sysdeps/x86_64/multiarch/memmove-sse2-unaligned-erms.S: Likwise. * sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S: Likwise. |
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| .. | ||
| aarch64 | ||
| alpha | ||
| arm | ||
| generic | ||
| gnu | ||
| hppa | ||
| i386 | ||
| ia64 | ||
| ieee754 | ||
| init_array | ||
| m68k | ||
| mach | ||
| microblaze | ||
| mips | ||
| nacl | ||
| nios2 | ||
| nptl | ||
| posix | ||
| powerpc | ||
| pthread | ||
| s390 | ||
| sh | ||
| sparc | ||
| tile | ||
| unix | ||
| wordsize-32 | ||
| wordsize-64 | ||
| x86 | ||
| x86_64 | ||