support signatures and param load/stores

build/context.go

@@ -5,6 +5,8 @@ import (
 	"io"
 	"log"
 
+	"github.com/mmcloughlin/avo/gotypes"
+
 	"github.com/mmcloughlin/avo"
 	"github.com/mmcloughlin/avo/reg"
 )
@@ -28,20 +30,33 @@ func (c *Context) Function(name string) {
 	c.file.Functions = append(c.file.Functions, c.function)
 }
 
+func (c *Context) Signature(s *gotypes.Signature) {
+	c.activefunc().SetSignature(s)
+}
+
+func (c *Context) SignatureExpr(expr string) {
+	s, err := gotypes.ParseSignature(expr)
+	if err != nil {
+		c.AddError(err)
+		return
+	}
+	c.Signature(s)
+}
+
 func (c *Context) Instruction(i *avo.Instruction) {
-	c.node(i)
+	c.activefunc().AddNode(i)
 }
 
 func (c *Context) Label(l avo.Label) {
-	c.node(l)
+	c.activefunc().AddLabel(l)
 }
 
-func (c *Context) node(n avo.Node) {
+func (c *Context) activefunc() *avo.Function {
 	if c.function == nil {
 		c.AddErrorMessage("no active function")
-		return
+		return avo.NewFunction("")
 	}
-	c.function.AddNode(n)
+	return c.function
 }
 
 //go:generate avogen -output zinstructions.go build

build/global.go

@@ -12,7 +12,11 @@ import (
 // ctx provides a global build context.
 var ctx = NewContext()
 
-func TEXT(name string)  { ctx.Function(name) }
+func TEXT(name, signature string) {
+	ctx.Function(name)
+	ctx.SignatureExpr(signature)
+}
+
 func LABEL(name string) { ctx.Label(avo.Label(name)) }
 
 var (

build/pseudo.go

@@ -8,11 +8,37 @@ import (
 
 //go:generate avogen -output zmov.go mov
 
-func (c *Context) Load(src gotypes.Component, dst reg.Register) {
+func (c *Context) Param(name string) gotypes.Component {
+	return c.activefunc().Signature.Params().Lookup(name)
+}
+
+func (c *Context) ParamIndex(i int) gotypes.Component {
+	return c.activefunc().Signature.Params().At(i)
+}
+
+func (c *Context) Return(name string) gotypes.Component {
+	return c.activefunc().Signature.Results().Lookup(name)
+}
+
+func (c *Context) ReturnIndex(i int) gotypes.Component {
+	return c.activefunc().Signature.Results().At(i)
+}
+
+func (c *Context) Load(src gotypes.Component, dst reg.Register) reg.Register {
 	b, err := src.Resolve()
+	if err != nil {
+		c.AddError(err)
+		return dst
+	}
+	c.mov(b.Addr, dst, int(gotypes.Sizes.Sizeof(b.Type)), int(dst.Bytes()), b.Type)
+	return dst
+}
+
+func (c *Context) Store(src reg.Register, dst gotypes.Component) {
+	b, err := dst.Resolve()
 	if err != nil {
 		c.AddError(err)
 		return
 	}
-	c.mov(b.Addr, dst, int(gotypes.Sizes.Sizeof(b.Type)), int(dst.Bytes()), b.Type)
+	c.mov(src, b.Addr, int(src.Bytes()), int(gotypes.Sizes.Sizeof(b.Type)), b.Type)
 }