Source
pub fn cacheLineForCpu(cpu: std.Target.Cpu) u16 {
return switch (cpu.arch) {
// x86_64: Starting from Intel's Sandy Bridge, the spatial prefetcher pulls in pairs of 64-byte cache lines at a time.
// - https://www.intel.com/content/dam/www/public/us/en/documents/manuals/64-ia-32-architectures-optimization-manual.pdf
// - https://github.com/facebook/folly/blob/1b5288e6eea6df074758f877c849b6e73bbb9fbb/folly/lang/Align.h#L107
//
// aarch64: Some big.LITTLE ARM archs have "big" cores with 128-byte cache lines:
// - https://www.mono-project.com/news/2016/09/12/arm64-icache/
// - https://cpufun.substack.com/p/more-m1-fun-hardware-information
//
// - https://github.com/torvalds/linux/blob/3a7e02c040b130b5545e4b115aada7bacd80a2b6/arch/arc/Kconfig#L212
// - https://github.com/golang/go/blob/3dd58676054223962cd915bb0934d1f9f489d4d2/src/internal/cpu/cpu_ppc64x.go#L9
.x86_64,
.aarch64,
.aarch64_be,
.arc,
.powerpc64,
.powerpc64le,
=> 128,
// https://github.com/llvm/llvm-project/blob/e379094328e49731a606304f7e3559d4f1fa96f9/clang/lib/Basic/Targets/Hexagon.h#L145-L151
.hexagon,
=> if (std.Target.hexagon.featureSetHas(cpu.features, .v73)) 64 else 32,
// - https://github.com/golang/go/blob/3dd58676054223962cd915bb0934d1f9f489d4d2/src/internal/cpu/cpu_arm.go#L7
// - https://github.com/golang/go/blob/3dd58676054223962cd915bb0934d1f9f489d4d2/src/internal/cpu/cpu_mips.go#L7
// - https://github.com/golang/go/blob/3dd58676054223962cd915bb0934d1f9f489d4d2/src/internal/cpu/cpu_mipsle.go#L7
// - https://github.com/golang/go/blob/3dd58676054223962cd915bb0934d1f9f489d4d2/src/internal/cpu/cpu_mips64x.go#L9
// - https://github.com/torvalds/linux/blob/3a7e02c040b130b5545e4b115aada7bacd80a2b6/arch/sparc/include/asm/cache.h#L14
.arm,
.armeb,
.thumb,
.thumbeb,
.mips,
.mipsel,
.mips64,
.mips64el,
.sparc,
.sparc64,
=> 32,
// - https://github.com/torvalds/linux/blob/3a7e02c040b130b5545e4b115aada7bacd80a2b6/arch/m68k/include/asm/cache.h#L10
.m68k,
=> 16,
// - https://www.ti.com/lit/pdf/slaa498
.msp430,
=> 8,
// - https://github.com/golang/go/blob/3dd58676054223962cd915bb0934d1f9f489d4d2/src/internal/cpu/cpu_s390x.go#L7
// - https://sxauroratsubasa.sakura.ne.jp/documents/guide/pdfs/Aurora_ISA_guide.pdf
.s390x,
.ve,
=> 256,
// Other x86 and WASM platforms have 64-byte cache lines.
// The rest of the architectures are assumed to be similar.
// - https://github.com/golang/go/blob/dda2991c2ea0c5914714469c4defc2562a907230/src/internal/cpu/cpu_x86.go#L9
// - https://github.com/golang/go/blob/0a9321ad7f8c91e1b0c7184731257df923977eb9/src/internal/cpu/cpu_loong64.go#L11
// - https://github.com/golang/go/blob/3dd58676054223962cd915bb0934d1f9f489d4d2/src/internal/cpu/cpu_wasm.go#L7
// - https://github.com/golang/go/blob/19e923182e590ae6568c2c714f20f32512aeb3e3/src/internal/cpu/cpu_riscv64.go#L7
// - https://github.com/torvalds/linux/blob/3a7e02c040b130b5545e4b115aada7bacd80a2b6/arch/xtensa/variants/csp/include/variant/core.h#L209
// - https://github.com/torvalds/linux/blob/3a7e02c040b130b5545e4b115aada7bacd80a2b6/arch/csky/Kconfig#L183
// - https://www.xmos.com/download/The-XMOS-XS3-Architecture.pdf
else => 64,
};
}