1 files changed, 151 insertions, 0 deletions
diff --git a/vendor/github.com/mmcloughlin/avo/operand/types.go b/vendor/github.com/mmcloughlin/avo/operand/types.go
new file mode 100644
index 0000000..878425e
--- /dev/null
+++ b/vendor/github.com/mmcloughlin/avo/operand/types.go
@@ -0,0 +1,151 @@
+package operand
+
+import (
+	"fmt"
+
+	"github.com/mmcloughlin/avo/reg"
+)
+
+// Op is an operand.
+type Op interface {
+	Asm() string
+}
+
+// Symbol represents a symbol name.
+type Symbol struct {
+	Name   string
+	Static bool // only visible in current source file
+}
+
+// NewStaticSymbol builds a static Symbol. Static symbols are only visible in the current source file.
+func NewStaticSymbol(name string) Symbol {
+	return Symbol{Name: name, Static: true}
+}
+
+func (s Symbol) String() string {
+	n := s.Name
+	if s.Static {
+		n += "<>"
+	}
+	return n
+}
+
+// Mem represents a memory reference.
+type Mem struct {
+	Symbol Symbol
+	Disp   int
+	Base   reg.Register
+	Index  reg.Register
+	Scale  uint8
+}
+
+// NewParamAddr is a convenience to build a Mem operand pointing to a function
+// parameter, which is a named offset from the frame pointer pseudo register.
+func NewParamAddr(name string, offset int) Mem {
+	return Mem{
+		Symbol: Symbol{
+			Name:   name,
+			Static: false,
+		},
+		Disp: offset,
+		Base: reg.FramePointer,
+	}
+}
+
+// NewStackAddr returns a memory reference relative to the stack pointer.
+func NewStackAddr(offset int) Mem {
+	return Mem{
+		Disp: offset,
+		Base: reg.StackPointer,
+	}
+}
+
+// NewDataAddr returns a memory reference relative to the named data symbol.
+func NewDataAddr(sym Symbol, offset int) Mem {
+	return Mem{
+		Symbol: sym,
+		Disp:   offset,
+		Base:   reg.StaticBase,
+	}
+}
+
+// Offset returns a reference to m plus idx bytes.
+func (m Mem) Offset(idx int) Mem {
+	a := m
+	a.Disp += idx
+	return a
+}
+
+// Idx returns a new memory reference with (Index, Scale) set to (r, s).
+func (m Mem) Idx(r reg.Register, s uint8) Mem {
+	a := m
+	a.Index = r
+	a.Scale = s
+	return a
+}
+
+// Asm returns an assembly syntax representation of m.
+func (m Mem) Asm() string {
+	a := m.Symbol.String()
+	if a != "" {
+		a += fmt.Sprintf("%+d", m.Disp)
+	} else if m.Disp != 0 {
+		a += fmt.Sprintf("%d", m.Disp)
+	}
+	if m.Base != nil {
+		a += fmt.Sprintf("(%s)", m.Base.Asm())
+	}
+	if m.Index != nil && m.Scale != 0 {
+		a += fmt.Sprintf("(%s*%d)", m.Index.Asm(), m.Scale)
+	}
+	return a
+}
+
+// Rel is an offset relative to the instruction pointer.
+type Rel int32
+
+// Asm returns an assembly syntax representation of r.
+func (r Rel) Asm() string {
+	return fmt.Sprintf(".%+d", r)
+}
+
+// LabelRef is a reference to a label.
+type LabelRef string
+
+// Asm returns an assembly syntax representation of l.
+func (l LabelRef) Asm() string {
+	return string(l)
+}
+
+// Registers returns the list of all operands involved in the given operand.
+func Registers(op Op) []reg.Register {
+	switch op := op.(type) {
+	case reg.Register:
+		return []reg.Register{op}
+	case Mem:
+		var r []reg.Register
+		if op.Base != nil {
+			r = append(r, op.Base)
+		}
+		if op.Index != nil {
+			r = append(r, op.Index)
+		}
+		return r
+	case Constant, Rel, LabelRef:
+		return nil
+	}
+	panic("unknown operand type")
+}
+
+// ApplyAllocation returns an operand with allocated registers replaced. Registers missing from the allocation are left alone.
+func ApplyAllocation(op Op, a reg.Allocation) Op {
+	switch op := op.(type) {
+	case reg.Register:
+		return a.LookupRegisterDefault(op)
+	case Mem:
+		op.Base = a.LookupRegisterDefault(op.Base)
+		op.Index = a.LookupRegisterDefault(op.Index)
+		return op
+	}
+	return op
+}