// Non-preemptible because it is used by write barriers.
//
//go:nowritebarrier
//go:nosplit
func inheap(b uintptr) bool {
	return spanOfHeap(b) != nil
}

// inHeapOrStack is a variant of inheap that returns true for pointers
// into any allocated heap span.
//
//go:nowritebarrier
//go:nosplit
func inHeapOrStack(b uintptr) bool {
	s := spanOf(b)
	if s == nil || b < s.base() {

			//
			// (We will filter out the extra tests explicitly in computePatternAll.)
			wantTest = true

		case ld.allPatternIsRoot && ld.allClosesOverTests && new.has(pkgInAll):
			// This variant of the "all" pattern includes imports of tests of every
			// package that is itself in "all", and pkg is in "all", so its test is
			// also in "all" (as above).
			wantTest = true

This will be checked at the end of configuring variant configurations, as they are locked against further mutation.

If the set of attributes is shared across configurations, consider adding an additional attribute to one of the variants for the sole purpose of disambiguation.

		int64) (relocatedOffset int64, nExtReloc int, ok bool)
	// Archrelocvariant is a second arch-specific hook used for
	// relocation processing; it handles relocations where r.Type is
	// insufficient to describe the relocation (r.Variant !=
	// sym.RV_NONE). Here "rel" is the relocation being applied, "sym"
	// is the symbol containing the chunk of data to which the
	// relocation applies, and "off" is the contents of the

    => (SET(B|AE)  (BTQconst [int8(log32(c))] x))
(SET(NE|EQ) (TESTQ (MOVQconst [c]) x)) && isUint64PowerOfTwo(c)
    => (SET(B|AE)  (BTQconst [int8(log64(c))] x))
// SET..store variant
(SET(NE|EQ)store [off] {sym} ptr (TESTL (SHLL (MOVLconst [1]) x) y) mem)
    => (SET(B|AE)store  [off] {sym} ptr (BTL x y) mem)
(SET(NE|EQ)store [off] {sym} ptr (TESTQ (SHLQ (MOVQconst [1]) x) y) mem)