// them altogether.
	ap = a.Needzero()
	bp = b.Needzero()
	if ap != bp {
		return ap
	}

	// Sort variables in descending alignment order, so we can optimally
	// pack variables into the frame.
	if a.Type().Alignment() != b.Type().Alignment() {
		return a.Type().Alignment() > b.Type().Alignment()
	}

	// Sort normal variables before open-coded-defer slots, so that the
	// latter are grouped together and near the top of the frame (to

	&& isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && isSamePtr(p4, p5) && isSamePtr(p5, p6)
	&& t2.Alignment() <= t1.Alignment()
	&& t3.Alignment() <= t1.Alignment()
	&& t4.Alignment() <= t1.Alignment()
	&& t5.Alignment() <= t1.Alignment()
	&& t6.Alignment() <= t1.Alignment()
	&& registerizable(b, t2)
	&& registerizable(b, t3)
	&& registerizable(b, t4)
	&& registerizable(b, t5)

// T is "special" because of the unnamed field, so it needs a generated equality function.
// T is an odd number of bytes in size and has alignment 1.
type T struct {
	src [8]byte
	_   byte
}

// U contains 8 copies of T, each at a different %8 alignment.
type U [8]T

//go:noinline
func f(x, y *U) bool {
	return *x == *y
}

func main() {
	var a U
	_ = f(&a, &a)

		if powerOfTwo(size) { // bump alignment once in a while
			if size >= 2048 {
				align = 256
			} else if size >= 128 {
				align = size / 8
			} else if size >= 32 {
				align = 16 // heap bitmaps assume 16 byte alignment for allocations >= 32 bytes.
			}
		}
		if !powerOfTwo(align) {
			panic("incorrect alignment")
		}

		// Make the allocnpages big enough that

func parseNotes(reader io.Reader, alignment int, order binary.ByteOrder) ([]elfNote, error) {
	r := bufio.NewReader(reader)

	// padding returns the number of bytes required to pad the given size to an
	// alignment boundary.
	padding := func(size int) int {
		return ((size + (alignment - 1)) &^ (alignment - 1)) - size
	}

	var notes []elfNote
	for {

// AlignmentPadding bytes to add to align code as requested.
// Alignment is restricted to powers of 2 between 8 and 2048 inclusive.
//
// pc_: current offset in function, in bytes
// p:  a PCALIGN or PCALIGNMAX prog
// ctxt: the context, for current function
// cursym: current function being assembled
// returns number of bytes of padding needed,
// updates minimum alignment for the function.

	FileAttributes uint32

	// Pad out to 8-byte alignment.
	//
	// Without this padding, TestChmod fails due to an argument validation error
	// in SetFileInformationByHandle on windows/386.
	//
	// https://learn.microsoft.com/en-us/cpp/build/reference/zp-struct-member-alignment?view=msvc-170
	// says that “The C/C++ headers in the Windows SDK assume the platform's
	// default alignment is used.” What we see here is padding rather than

a cost of an additional 0.1% text and binary size.  This is currently only implemented
on 386 and amd64 because it has not shown an improvement on other platforms.
Hot block alignment can be disabled with `-gcflags=[<packages>=]-d=alignhot=0`

## Assembler {#assembler}

## Linker {#linker}

<!-- go.dev/issue/67401, CL 585556, CL 587220, and many more -->

//    65      27264       81920        3         128     10.00%        128
//    66      28672       57344        2           0      4.91%       4096
//    67      32768       32768        1           0     12.50%       8192

// alignment  bits  min obj size
//         8     3             8
//        16     4            32
//        32     5           256
//        64     6           512
//       128     7           768
//      4096    12         28672

//	e := unsafe.Pointer(uintptr(unsafe.Pointer(&x[0])) + i*unsafe.Sizeof(x[0]))
//
// It is valid both to add and to subtract offsets from a pointer in this way.
// It is also valid to use &^ to round pointers, usually for alignment.
// In all cases, the result must continue to point into the original allocated object.
//
// Unlike in C, it is not valid to advance a pointer just beyond the end of
// its original allocation:
//