func (s *regAllocState) init(f *Func) {
	s.f = f
	s.f.RegAlloc = s.f.Cache.locs[:0]
	s.registers = f.Config.registers
	if nr := len(s.registers); nr == 0 || nr > int(noRegister) || nr > int(unsafe.Sizeof(regMask(0))*8) {
		s.f.Fatalf("bad number of registers: %d", nr)
	} else {
		s.numRegs = register(nr)
	}
	// Locate SP, SB, and g registers.
	s.SPReg = noRegister
	s.SBReg = noRegister
	s.GReg = noRegister

	} else {
		state.currentState.slots = state.currentState.slots[:numSlots]
	}
	if cap(state.currentState.registers) < len(state.registers) {
		state.currentState.registers = make([][]SlotID, len(state.registers))
	} else {
		state.currentState.registers = state.currentState.registers[:len(state.registers)]
	}

	// A relatively small slice, but used many times as the return from processValue.

	SUBQ	R11, R12
	MOVQ	R12, R11
	// Restore registers.
	MOVQ	96(SP), R12
	MOVQ	104(SP), R13
	RET

flush:
	// Save all general purpose registers since these could be
	// clobbered by wbBufFlush and were not saved by the caller.
	// It is possible for wbBufFlush to clobber other registers
	// (e.g., SSE registers), but the compiler takes care of saving

	"F6",
	"F7",
	"F8",
	"F9",
	"F10",
	"F11",
	"F12",
	"F13",
	"F14",
	"F15",

	// If you add registers, update asyncPreempt in runtime.

	//pseudo-registers
	"SB",
}

func init() {
	// Make map from reg names to reg integers.
	if len(regNamesS390X) > 64 {
		panic("too many registers")
	}
	num := map[string]int{}
	for i, name := range regNamesS390X {
		num[name] = i
	}

	"F23",
	"F24",
	"F25",
	"F26",
	"F27",
	"F28",
	"F29",
	"F30",
	"F31",

	// If you add registers, update asyncPreempt in runtime.

	// pseudo-registers
	"SB",
}

func init() {
	// Make map from reg names to reg integers.
	if len(regNamesARM64) > 64 {
		panic("too many registers")
	}
	num := map[string]int{}
	for i, name := range regNamesARM64 {
		num[name] = i
	}

	// TODO(danscales): choose a better name.
	rparams *[]*Type
}

// Registers returns the number of integer and floating-point
// registers required to represent a parameter of this type under the
// ABIInternal calling conventions.
//
// If t must be passed by memory, Registers returns (math.MaxUint8,
// math.MaxUint8).
func (t *Type) Registers() (uint8, uint8) {
	CalcSize(t)
	return t.intRegs, t.floatRegs
}

	VEXTRACTPS $-1, X1, AX       // c4e37917c8ff
	VPEXTRB $-1, X1, AX          // c4e37914c8ff
	VPEXTRD $-1, X1, AX          // c4e37916c8ff
	VPEXTRQ $-1, X1, AX          // c4e3f916c8ff
	// EVEX: High-16 X registers.
	VADDPD X30, X1, X0          // 6291f50858c6
	VADDPD X2, X29, X0          // 62f1950058c2
	VADDPD X30, X29, X0         // 6291950058c6
	VADDPD X2, X1, X28          // 6261f50858e2

<2> Registers a new untyped task named `myTask1`
<3> Gets a reference to the existing task named `compileJava` of type `JavaCompile`
<4> Registers a new task named `myCopy1` of type `Copy`
<5> Gets a reference to the existing (untyped) task named `assemble` and configures it — you can only configure properties and methods that are available on `Task` with this syntax

// runtime.elf_restvr+(m-20)*8, and similar.
//
// These functions are defined in the ELFv2 ABI (generated when using gcc -Os option) to save and
// restore callee-saved registers (as defined in the PPC64 ELF ABIs) from registers n or m to 31 of
// the named type. R12 and R0 are sometimes used in exceptional ways described in the ABI.
//

// The most important fact about a given architecture is whether it uses a link register.
// On systems with link registers, the prologue for a non-leaf function stores the
// incoming value of LR at the bottom of the newly allocated stack frame.
// On systems without link registers (x86), the architecture pushes a return PC during
// the call instruction, so the return PC ends up above the stack frame.