add riscv64 CPU compatibility#257
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Add a riscv64 branch that uses the Zihintpause pause instruction when the target enables it, otherwise falls back to a nop that is valid for the baseline ISA. Read the Linux device-tree timebase-frequency value from procfs or sysfs as the counter frequency, and use rdtime for timestamps so both helpers use the RISC-V time counter units.
tzcnt
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Jun 20, 2026
| } | ||
| } | ||
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| __builtin_unreachable(); |
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Please add a fallback return value if this is not available. This value is used for heuristics only as described on line 78, so please choose a reasonable value for a RISC-V chip that supports multi-core / multi-thread.
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Additionally, I think this needs an #ifdef __linux__ check. If not defined, we should also return a fallback.
| #include <atomic> | ||
| #include <cstddef> | ||
| #include <cstdint> | ||
| #include <cstdio> |
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Please move this include inside of the #if defined(__riscv) block. This header is included almost everywhere in the project, so I try to keep it as slim as possible.
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Add a riscv64 branch that uses the Zihintpause pause instruction when the target enables it, otherwise falls back to a nop that is valid for the baseline ISA.
Read the Linux device-tree timebase-frequency value from procfs or sysfs as the counter frequency, and use rdtime for timestamps so both helpers use the RISC-V time counter units.