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Robert Schulze 2023-03-01 09:34:46 +00:00
parent 79523ed356
commit ac7caace8a
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@ -30,7 +30,7 @@ elseif (ARCH_AARCH64)
# support it.
set (COMPILER_FLAGS "${COMPILER_FLAGS} -march=armv8+crc")
else ()
# ARMv8.2 is quite ancient but the lowest common denominator supported by both Graviton 2 and 3 processors [1]. In particular, it
# ARMv8.2 is quite ancient but the lowest common denominator supported by both Graviton 2 and 3 processors [1, 10]. In particular, it
# includes LSE (made mandatory with ARMv8.1) which provides nice speedups without having to fall back to compat flag
# "-moutline-atomics" for v8.0 [2, 3, 4] that requires a recent glibc with runtime dispatch helper, limiting our ability to run on
# old OSs.
@ -45,18 +45,19 @@ elseif (ARCH_AARCH64)
# dotprod: Scalar vector product (SDOT and UDOT instructions). Probably the most obscure extra flag with doubtful performance benefits
# but it has been activated since always, so why not enable it. It's not 100% clear in which revision this flag was
# introduced as optional, either in v8.2 [7] or in v8.4 [8].
# ldapr: Load-Acquire RCpc Register. Better support of release/acquire of atomics. Good for allocators and high contention code.
# Optional in v8.2, mandatory in v8.3 [9]. Supported in Graviton 2+, Azure and GCP instances. Generated from clang 15.
# rcpc: Load-Acquire RCpc Register. Better support of release/acquire of atomics. Good for allocators and high contention code.
# Optional in v8.2, mandatory in v8.3 [9]. Supported in Graviton >=2, Azure and GCP instances.
#
# [1] https://github.com/aws/aws-graviton-getting-started/blob/main/c-c%2B%2B.md
# [2] https://community.arm.com/arm-community-blogs/b/tools-software-ides-blog/posts/making-the-most-of-the-arm-architecture-in-gcc-10
# [3] https://mysqlonarm.github.io/ARM-LSE-and-MySQL/
# [4] https://dev.to/aws-builders/large-system-extensions-for-aws-graviton-processors-3eci
# [5] https://developer.arm.com/tools-and-software/open-source-software/developer-tools/llvm-toolchain/sve-support
# [6] https://developer.arm.com/documentation/100067/0612/armclang-Command-line-Options/-mcpu?lang=en
# [7] https://gcc.gnu.org/onlinedocs/gcc/ARM-Options.html
# [8] https://developer.arm.com/documentation/102651/a/What-are-dot-product-intructions-
# [9] https://developer.arm.com/documentation/dui0801/g/A64-Data-Transfer-Instructions/LDAPR?lang=en
# [1] https://github.com/aws/aws-graviton-getting-started/blob/main/c-c%2B%2B.md
# [2] https://community.arm.com/arm-community-blogs/b/tools-software-ides-blog/posts/making-the-most-of-the-arm-architecture-in-gcc-10
# [3] https://mysqlonarm.github.io/ARM-LSE-and-MySQL/
# [4] https://dev.to/aws-builders/large-system-extensions-for-aws-graviton-processors-3eci
# [5] https://developer.arm.com/tools-and-software/open-source-software/developer-tools/llvm-toolchain/sve-support
# [6] https://developer.arm.com/documentation/100067/0612/armclang-Command-line-Options/-mcpu?lang=en
# [7] https://gcc.gnu.org/onlinedocs/gcc/ARM-Options.html
# [8] https://developer.arm.com/documentation/102651/a/What-are-dot-product-intructions-
# [9] https://developer.arm.com/documentation/dui0801/g/A64-Data-Transfer-Instructions/LDAPR?lang=en
# [10] https://github.com/aws/aws-graviton-getting-started/blob/main/README.md
set (COMPILER_FLAGS "${COMPILER_FLAGS} -march=armv8.2-a+simd+crypto+dotprod+ssbs+rcpc")
endif ()