AArch64: Implement arraycmp evaluator #6904
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This commit implements arraycmp evaluator. It implements two variants. One of them returns the length of the identical data from the beginning of the arrays. The other returns 2/0/1 when the first array is greater than/equal to/less than the second array. The main loop reads a 16-byte chunk from the both array in a single interation. It uses ldp instruction to read 16-byte data into two 64-bit registers. Then, it compares each 64-bit registers to find mismatch. If any mismatch is found in 16-byte chunks, the bit position of the first mismatch is searched by clz instruction for the variant returning the length. If no mismatch is found in 16-byte chunks and there is still remaining data to be compared (which is smaller than 16 bytes), the secondary loop, which reads a single byte in each iteration, is executed. Signed-off-by: Akira Saitoh <[email protected]>
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|
Jenkins build aarch64,amac |
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See Issue #6516 for the socket test failure on macOS. |
knn-k
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This commit implements arraycmp evaluator.
It implements two variants. One of them returns the length of the identical data from the beginning of the arrays.
The other returns 2/0/1 when the first array is greater than/equal to/less than the second array.
The main loop reads a 16-byte chunk from the both array in a single interation. It uses ldp instruction to read 16-byte data into two 64-bit registers. Then, it compares each 64-bit registers to find mismatch. If any mismatch is found in 16-byte chunks, the bit position of the first mismatch is searched by clz instruction for the variant returning the length. If no mismatch is found in 16-byte chunks and there is still remaining data to be compared (which is smaller than 16 bytes),
the secondary loop, which reads a single byte in each iteration, is executed.