package sys

Import Path
	runtime/internal/sys (on go.dev)

Dependency Relation
	imports 2 packages, and imported by one package


Involved Source Files

	      consts.go
	      intrinsics.go
	      intrinsics_common.go
	
		package sys contains system- and configuration- and architecture-specific
		constants used by the runtime.

	      zversion.go


Package-Level Functions (total 14, all are exported)


	
		Bswap32 returns its input with byte order reversed
		0x01020304 -> 0x04030201


	
		Bswap64 returns its input with byte order reversed
		0x0102030405060708 -> 0x0807060504030201


	
		Ctz32 counts trailing (low-order) zeroes,
		and if all are zero, then 32.


	
		Ctz64 counts trailing (low-order) zeroes,
		and if all are zero, then 64.


	
		Ctz8 returns the number of trailing zero bits in x; the result is 8 for x == 0.


	
		LeadingZeros64 returns the number of leading zero bits in x; the result is 64 for x == 0.


	
		LeadingZeros8 returns the number of leading zero bits in x; the result is 8 for x == 0.


	
		len64 returns the minimum number of bits required to represent x; the result is 0 for x == 0.


	
		Len8 returns the minimum number of bits required to represent x; the result is 0 for x == 0.


	
		OnesCount64 returns the number of one bits ("population count") in x.


	
		Prefetch prefetches data from memory addr to cache

		AMD64: Produce PREFETCHT0 instruction

		ARM64: Produce PRFM instruction with PLDL1KEEP option


	
		PrefetchStreamed prefetches data from memory addr, with a hint that this data is being streamed.
		That is, it is likely to be accessed very soon, but only once. If possible, this will avoid polluting the cache.

		AMD64: Produce PREFETCHNTA instruction

		ARM64: Produce PRFM instruction with PLDL1STRM option


	
		TrailingZeros64 returns the number of trailing zero bits in x; the result is 64 for x == 0.


	
		TrailingZeros8 returns the number of trailing zero bits in x; the result is 8 for x == 0.




Package-Level Variables (total 5, none are exported)

	


Package-Level Constants (total 13, in which 7 are exported)


	
		DefaultPhysPageSize is the default physical page size.


	
		Int64Align is the required alignment for a 64-bit integer (4 on 32-bit systems, 8 on 64-bit).


	
		MinFrameSize is the size of the system-reserved words at the bottom
		of a frame (just above the architectural stack pointer).
		It is zero on x86 and PtrSize on most non-x86 (LR-based) systems.
		On PowerPC it is larger, to cover three more reserved words:
		the compiler word, the link editor word, and the TOC save word.


	
		PCQuantum is the minimal unit for a program counter (1 on x86, 4 on most other systems).
		The various PC tables record PC deltas pre-divided by PCQuantum.


	
		StackAlign is the required alignment of the SP register.
		The stack must be at least word aligned, but some architectures require more.


	
		AIX requires a larger stack for syscalls.