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Add CMO extension intrinsics #93

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Add CMO extension intrinsics #93

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23 changes: 23 additions & 0 deletions src/c-api.adoc
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Expand Up @@ -485,6 +485,29 @@ RISC-V intrinsics examples:
vint8m1_t __riscv_vadd_vv_i8m1(vint8m1_t vs2, vint8m1_t vs1, size_t vl); // vadd.vv vd, vs2, vs1
----

=== CMO Intrinsics

The RISC-V CMO extension provides instruction for perform operations on copies
of data in the memory hierarchy.

In order to access the RISC-V CMO intrinsics, it is necessary to
include the header file `riscv_cmo.h`.

The functions are only available if the compiler's `-march` string enables the
required ISA extension.

.CMO Extension Intrinsics
[%autowidth]
|===
|*Prototype* |*Instruction* |*Extension*
|`+void __riscv_cbo_clean(void *addr);+` |`cbo.clean` |Zicbom
|`+void __riscv_cbo_flush(void *addr);+` |`cbo.flush` |Zicbom
|`+void __riscv_cbo_inval(void *addr);+` |`cbo.inval` |Zicbom
|`+void __riscv_cbo_zero(void *addr);+` |`cbo.zero` |Zicboz
|`+void __riscv_cbo_prefetch(void *addr, const int rw, const int locality);+` |`prefetch.[r][w]` |Zicbop
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Is __riscv_cbo_prefetch a wrapper around __builtin_prefetch where there are 4 possible localities? RISC-V supports 5 localities, 4 NTL hint prefixes and 1 without any prefix.

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Yes, this is __builtin_prefetch's wrapper. The 4 NTL hint maping had been included in Prefetch Intrinsics part on this doc. So, this commit only support a wrapper for __builtin_prefetch on zicbop extension.

|`+int __riscv_cbo_prefetchi(const int locality);+` |`prefetch.i` |Zicbop
|===

=== NTLH Intrinsics


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