diff options
Diffstat (limited to 'kernel/arch/arm64/lib/memcpy.S')
-rw-r--r-- | kernel/arch/arm64/lib/memcpy.S | 184 |
1 files changed, 30 insertions, 154 deletions
diff --git a/kernel/arch/arm64/lib/memcpy.S b/kernel/arch/arm64/lib/memcpy.S index 8a9a96d3d..676139377 100644 --- a/kernel/arch/arm64/lib/memcpy.S +++ b/kernel/arch/arm64/lib/memcpy.S @@ -36,166 +36,42 @@ * Returns: * x0 - dest */ -dstin .req x0 -src .req x1 -count .req x2 -tmp1 .req x3 -tmp1w .req w3 -tmp2 .req x4 -tmp2w .req w4 -tmp3 .req x5 -tmp3w .req w5 -dst .req x6 + .macro ldrb1 ptr, regB, val + ldrb \ptr, [\regB], \val + .endm -A_l .req x7 -A_h .req x8 -B_l .req x9 -B_h .req x10 -C_l .req x11 -C_h .req x12 -D_l .req x13 -D_h .req x14 + .macro strb1 ptr, regB, val + strb \ptr, [\regB], \val + .endm -ENTRY(memcpy) - mov dst, dstin - cmp count, #16 - /*When memory length is less than 16, the accessed are not aligned.*/ - b.lo .Ltiny15 + .macro ldrh1 ptr, regB, val + ldrh \ptr, [\regB], \val + .endm - neg tmp2, src - ands tmp2, tmp2, #15/* Bytes to reach alignment. */ - b.eq .LSrcAligned - sub count, count, tmp2 - /* - * Copy the leading memory data from src to dst in an increasing - * address order.By this way,the risk of overwritting the source - * memory data is eliminated when the distance between src and - * dst is less than 16. The memory accesses here are alignment. - */ - tbz tmp2, #0, 1f - ldrb tmp1w, [src], #1 - strb tmp1w, [dst], #1 -1: - tbz tmp2, #1, 2f - ldrh tmp1w, [src], #2 - strh tmp1w, [dst], #2 -2: - tbz tmp2, #2, 3f - ldr tmp1w, [src], #4 - str tmp1w, [dst], #4 -3: - tbz tmp2, #3, .LSrcAligned - ldr tmp1, [src],#8 - str tmp1, [dst],#8 + .macro strh1 ptr, regB, val + strh \ptr, [\regB], \val + .endm -.LSrcAligned: - cmp count, #64 - b.ge .Lcpy_over64 - /* - * Deal with small copies quickly by dropping straight into the - * exit block. - */ -.Ltail63: - /* - * Copy up to 48 bytes of data. At this point we only need the - * bottom 6 bits of count to be accurate. - */ - ands tmp1, count, #0x30 - b.eq .Ltiny15 - cmp tmp1w, #0x20 - b.eq 1f - b.lt 2f - ldp A_l, A_h, [src], #16 - stp A_l, A_h, [dst], #16 -1: - ldp A_l, A_h, [src], #16 - stp A_l, A_h, [dst], #16 -2: - ldp A_l, A_h, [src], #16 - stp A_l, A_h, [dst], #16 -.Ltiny15: - /* - * Prefer to break one ldp/stp into several load/store to access - * memory in an increasing address order,rather than to load/store 16 - * bytes from (src-16) to (dst-16) and to backward the src to aligned - * address,which way is used in original cortex memcpy. If keeping - * the original memcpy process here, memmove need to satisfy the - * precondition that src address is at least 16 bytes bigger than dst - * address,otherwise some source data will be overwritten when memove - * call memcpy directly. To make memmove simpler and decouple the - * memcpy's dependency on memmove, withdrew the original process. - */ - tbz count, #3, 1f - ldr tmp1, [src], #8 - str tmp1, [dst], #8 -1: - tbz count, #2, 2f - ldr tmp1w, [src], #4 - str tmp1w, [dst], #4 -2: - tbz count, #1, 3f - ldrh tmp1w, [src], #2 - strh tmp1w, [dst], #2 -3: - tbz count, #0, .Lexitfunc - ldrb tmp1w, [src] - strb tmp1w, [dst] + .macro ldr1 ptr, regB, val + ldr \ptr, [\regB], \val + .endm -.Lexitfunc: - ret + .macro str1 ptr, regB, val + str \ptr, [\regB], \val + .endm -.Lcpy_over64: - subs count, count, #128 - b.ge .Lcpy_body_large - /* - * Less than 128 bytes to copy, so handle 64 here and then jump - * to the tail. - */ - ldp A_l, A_h, [src],#16 - stp A_l, A_h, [dst],#16 - ldp B_l, B_h, [src],#16 - ldp C_l, C_h, [src],#16 - stp B_l, B_h, [dst],#16 - stp C_l, C_h, [dst],#16 - ldp D_l, D_h, [src],#16 - stp D_l, D_h, [dst],#16 + .macro ldp1 ptr, regB, regC, val + ldp \ptr, \regB, [\regC], \val + .endm - tst count, #0x3f - b.ne .Ltail63 - ret + .macro stp1 ptr, regB, regC, val + stp \ptr, \regB, [\regC], \val + .endm - /* - * Critical loop. Start at a new cache line boundary. Assuming - * 64 bytes per line this ensures the entire loop is in one line. - */ - .p2align L1_CACHE_SHIFT -.Lcpy_body_large: - /* pre-get 64 bytes data. */ - ldp A_l, A_h, [src],#16 - ldp B_l, B_h, [src],#16 - ldp C_l, C_h, [src],#16 - ldp D_l, D_h, [src],#16 -1: - /* - * interlace the load of next 64 bytes data block with store of the last - * loaded 64 bytes data. - */ - stp A_l, A_h, [dst],#16 - ldp A_l, A_h, [src],#16 - stp B_l, B_h, [dst],#16 - ldp B_l, B_h, [src],#16 - stp C_l, C_h, [dst],#16 - ldp C_l, C_h, [src],#16 - stp D_l, D_h, [dst],#16 - ldp D_l, D_h, [src],#16 - subs count, count, #64 - b.ge 1b - stp A_l, A_h, [dst],#16 - stp B_l, B_h, [dst],#16 - stp C_l, C_h, [dst],#16 - stp D_l, D_h, [dst],#16 - - tst count, #0x3f - b.ne .Ltail63 + .weak memcpy +ENTRY(__memcpy) +ENTRY(memcpy) +#include "copy_template.S" ret -ENDPROC(memcpy) +ENDPIPROC(memcpy) +ENDPROC(__memcpy) |