// newBlock appends a new unconnected basic block to b.cfg's block
// slice and returns it.
// It does not automatically become the current block.
// comment is an optional string for more readable debugging output.
func (b *builder) newBlock(kind BlockKind, stmt ast.Stmt) *Block {
	g := b.cfg
	block := &Block{
		Index: int32(len(g.Blocks)),
		Kind:  kind,
		Stmt:  stmt,
	}
	block.Succs = block.succs2[:0]

			}
			c := b.Preds[0].Block()
			d := b.Preds[1].Block()

			// Find their common predecessor block (the one that branches based on wb on/off).
			// It might be a diamond pattern, or one of the blocks in the diamond pattern might
			// be missing.
			var decisionBlock *ssa.Block
			if len(c.Preds) == 1 && c.Preds[0].Block() == d {
				decisionBlock = d

	f.freeValues = v
}

// NewBlock allocates a new Block of the given kind and places it at the end of f.Blocks.
func (f *Func) NewBlock(kind BlockKind) *Block {
	var b *Block
	if f.freeBlocks != nil {
		b = f.freeBlocks
		f.freeBlocks = b.succstorage[0].b
		b.succstorage[0].b = nil
	} else {
		ID := f.bid.get()
		if int(ID) < len(f.Cache.blocks) {
			b = &f.Cache.blocks[ID]
			b.ID = ID
		} else {

 */
```

## 1.3 Code blocks and snippets

`<pre>` is the default HTML tag for preformatted text.
All code blocks and multi-line snippets should be wrapped in `<pre>{@code ...... }</pre>` at minimum.

Code blocks can be optionally formatted and highlighted using [`highlight.js`](https://highlightjs.org/) with the `<code>` tag.

		// If there are no direct-only or indirect-only blocks, a new block may
		// be inserted after the last require line or block.
		lastRequireIndex = -1

		// If there's only one require line or block, and it's uncommented,
		// we'll move its requirements to the direct-only or indirect-only blocks.
		requireLineOrBlockCount = 0

		// Track the block each requirement belongs to (if any) so we can
		// move them later.

	*y = z
}

// updateBlocks extends y with more polynomial terms from blocks, based on
// Horner's rule. There must be a multiple of gcmBlockSize bytes in blocks.
func (g *gcm) updateBlocks(y *gcmFieldElement, blocks []byte) {
	for len(blocks) > 0 {
		y.low ^= byteorder.BeUint64(blocks)
		y.high ^= byteorder.BeUint64(blocks[8:])
		g.mul(y)
		blocks = blocks[gcmBlockSize:]
	}
}

	// inBlockUses records whether a value is used in the block
	// in which it lives. (block control values don't count as uses.)
	inBlockUses := f.Cache.allocBoolSlice(f.NumValues())
	defer f.Cache.freeBoolSlice(inBlockUses)
	if f.Config.optimize {
		for _, b := range f.Blocks {
			for _, v := range b.Values {
				for _, a := range v.Args {
					if a.Block == b {
						inBlockUses[a.ID] = true
					}
				}
			}

.dead-value span.highlight-aquamarine,
.dead-block.highlight-aquamarine,
.dead-value span.highlight-coral,
.dead-block.highlight-coral,
.dead-value span.highlight-lightpink,
.dead-block.highlight-lightpink,
.dead-value span.highlight-lightsteelblue,
.dead-block.highlight-lightsteelblue,
.dead-value span.highlight-palegreen,
.dead-block.highlight-palegreen,
.dead-value span.highlight-skyblue,
.dead-block.highlight-skyblue,

	default:
		t.f.Fatalf("All kind of block should be processed above.")
	}
}

// rewireSuccessor rewires corresponding successors according to constant value
// discovered by previous analysis. As the result, some successors become unreachable
// and thus can be removed in further deadcode phase
func rewireSuccessor(block *Block, constVal *Value) bool {
	switch block.Kind {
	case BlockIf:
		block.removeEdge(int(constVal.AuxInt))

	// long then it is easiest to insert the 1 before the message
	// block is split into 26-bit limbs. If, on the other hand, the
	// final message block is 16 bytes long then we append the 1 bit
	// after expansion as normal.
	MOVBZ  $1, R0
	MOVD   $-16(R3), R3   // index of byte in last block to insert 1 at (could be 16)