cpu: aarch64: remove branch target alignment #4517
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Remove branch target alignment from brgemm functions, reducing code size by ~10% and improving performance on Graviton 3/4 by ~0.5% (this required many repeated measurements to be confident of results). Branch alignment can affect performance, but it does not need to be the default, and it should be machine and kernel specific and evidence based. As another point of reference, arm_gemm in ComputeLibrary only uses nops in a single kernel `a64_sgemm_asimd_8x12_a53`, written for a core which we do not specifically target (and only then sparingly).
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Remove branch target alignment from brgemm functions, reducing code size by ~10% and improving performance on Graviton 3/4 by ~0.5% (this required many repeated measurements to be confident of results). Branch alignment can affect performance, but it does not need to be the default, and it should be machine and kernel specific and evidence based.
As another point of reference, arm_gemm in ComputeLibrary only uses nops in a single kernel
a64_sgemm_asimd_8x12_a53, written for a core which we do not specifically target (and only then sparingly).Checklist
General
make testandmake test_benchdnn_*) pass locally for each commit?Performance improvements