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2149da3683
The memcpy optimization (commit 587a1290a1) has a series
of mistakes:
- The implementation is wrong: the chunk size calculation is wrong
leading to invalid memory access.
- It adds ifunc supports as default, so --disable-multi-arch does
not work as expected for riscv.
- It mixes Linux files (memcpy ifunc selection which requires the
vDSO/syscall mechanism) with generic support (the memcpy
optimization itself).
- There is no __libc_ifunc_impl_list, which makes testing only
check the selected implementation instead of all supported
by the system.
This patch also simplifies the required bits to enable ifunc: there
is no need to memcopy.h; nor to add Linux-specific files.
The __memcpy_noalignment tail handling now uses a branchless strategy
similar to aarch64 (overlap 32-bits copies for sizes 4..7 and byte
copies for size 1..3).
Checked on riscv64 and riscv32 by explicitly enabling the function
on __libc_ifunc_impl_list on qemu-system.
Changes from v1:
* Implement the memcpy in assembly to correctly handle RISCV
strict-alignment.
Reviewed-by: Evan Green <evan@rivosinc.com>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
28 lines
720 B
Makefile
28 lines
720 B
Makefile
ifeq ($(subdir),misc)
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sysdep_headers += \
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sys/cachectl.h \
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sys/hwprobe.h \
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# sysdep_headers
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sysdep_routines += \
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flush-icache \
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hwprobe \
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# sysdep_routines
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endif
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ifeq ($(subdir),stdlib)
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gen-as-const-headers += ucontext_i.sym
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endif
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abi-variants := ilp32 ilp32d lp64 lp64d
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ifeq (,$(filter $(default-abi),$(abi-variants)))
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$(error Unknown ABI $(default-abi), must be one of $(abi-variants))
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endif
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abi-ilp32-condition := __WORDSIZE == 32 && defined __riscv_float_abi_soft
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abi-ilp32d-condition := __WORDSIZE == 32 && defined __riscv_float_abi_double
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abi-lp64-condition := __WORDSIZE == 64 && defined __riscv_float_abi_soft
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abi-lp64d-condition := __WORDSIZE == 64 && defined __riscv_float_abi_double
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