// destructor, as:
//
//   1. You cannot safely throw from a destructor.  This is a problem
//      as in some cases Google Test is used where exceptions are enabled, and
//      we may want to implement ASSERT_* using exceptions where they are
//      available.
//   2. You cannot use ASSERT_* directly in a constructor or
//      destructor.
class Environment {
 public:

// destructor, as:
//
//   1. You cannot safely throw from a destructor.  This is a problem
//      as in some cases Google Test is used where exceptions are enabled, and
//      we may want to implement ASSERT_* using exceptions where they are
//      available.
//   2. You cannot use ASSERT_* directly in a constructor or
//      destructor.
class Environment {
 public:

[[sec:how_does_it_work]]
== How does it work?

type encoding struct {
	encode   func(*instruction) uint32     // encode returns the machine code for an instruction
	validate func(*obj.Link, *instruction) // validate validates an instruction
	length   int                           // length of encoded instruction; 0 for pseudo-ops, 4 otherwise
}

var (
	// Encodings have the following naming convention:
	//
	//  1. the instruction encoding (R/I/S/B/U/J), in lowercase

	OP_ADDIS         = 0x3c000000 // addis
	OP_LD            = 0xe8000000 // ld
	OP_PLA_PFX       = 0x06100000 // pla (prefix instruction word)
	OP_PLA_SFX       = 0x38000000 // pla (suffix instruction word)
	OP_PLD_PFX_PCREL = 0x04100000 // pld (prefix instruction word, R=1)
	OP_PLD_SFX       = 0xe4000000 // pld (suffix instruction word)
	OP_MFLR          = 0x7c0802a6 // mflr
	OP_MTLR          = 0x7c0803a6 // mtlr
	OP_MFCTR         = 0x7c0902a6 // mfctr

// isRestartable returns whether p is a multi-instruction sequence that,
// if preempted, can be restarted.
func (c *ctxt0) isRestartable(p *obj.Prog) bool {
	if c.isUnsafePoint(p) {
		return false
	}
	// If p is a multi-instruction sequence with uses REGTMP inserted by
	// the assembler in order to materialize a large constant/offset, we
	// can restart p (at the start of the instruction sequence), recompute

	node = node.DeepCopy()
	if node.Labels == nil {
		node.Labels = map[string]string{}
	}
	if value == "" {
		value = "value"
	}
	// node restriction labels are forbidden
	node.Labels["node-restriction.kubernetes.io/foo"] = value
	node.Labels["foo.node-restriction.kubernetes.io/foo"] = value
	node.Labels["other.kubernetes.io/foo"] = value
	node.Labels["other.k8s.io/foo"] = value
	return node
}

// Specifically, this is the PC of the last instruction executed in this frame.
//
// If this frame did a normal call, then frame.pc is a return PC, so this will
// return frame.pc-1, which points into the CALL instruction. If the frame was
// interrupted by a signal (e.g., profiler, segv, etc) then frame.pc is for the
// trapped instruction, so this returns frame.pc. See issue #34123. Finally,

}, {
	desc: "proc instruction",
	toks: []Token{
		ProcInst{"Target", []byte("Instruction")},
	},
	want: `<?Target Instruction?>`,
}, {
	desc: "proc instruction with empty target",
	toks: []Token{
		ProcInst{"", []byte("Instruction")},
	},
	err: "xml: EncodeToken of ProcInst with invalid Target",
}, {
	desc: "proc instruction with bad content",
	toks: []Token{

// isRestartable returns whether p is a multi-instruction sequence that,
// if preempted, can be restarted.
func (c *ctxt0) isRestartable(p *obj.Prog) bool {
	if c.isUnsafePoint(p) {
		return false
	}
	// If p is a multi-instruction sequence with uses REGTMP inserted by
	// the assembler in order to materialize a large constant/offset, we
	// can restart p (at the start of the instruction sequence), recompute