WIP: more work on pointers.

README.md

@@ -267,6 +267,7 @@ form assembly:
      - [ ] local variables in for-loop unrolling
    - [ ] Pointer handling
      - [ ] Pointer to struct field
+   - [ ] Compound init values must be zero-padded to full size
    - [X] Method calls
    - [ ] Signed / unsigned arithmetics
    - [X] `byte` type

compiler/ast/codegen.go

@@ -120,6 +120,52 @@ func (ctx *Codegen) LookupFunc(block *ssa.Block, ref *VariableRef) (
 	return called, nil
 }
 
+// LookupVar resolved the named variable from the context.
+func (ctx *Codegen) LookupVar(bindings *ssa.Bindings, ref *VariableRef) (
+	ssa.Binding, bool, error) {
+
+	var b ssa.Binding
+	var ok bool
+
+	if len(ref.Name.Package) > 0 {
+		// Check if package name is bound to a value.
+		b, ok = bindings.Get(ref.Name.Package)
+		if !ok {
+			// Check names in the current package.
+			b, ok = ctx.Package.Bindings.Get(ref.Name.Package)
+		}
+		if ok {
+			return b, true, nil
+		}
+	}
+
+	// Name from environment bindings.
+	b, ok = bindings.Get(ref.Name.Name)
+	if ok {
+		return b, ok, nil
+	}
+
+	// Global symbols from the package.
+	var pkgName string
+	if len(ref.Name.Package) > 0 {
+		pkgName = ref.Name.Package
+	} else {
+		pkgName = ref.Name.Defined
+	}
+	pkg, ok := ctx.Packages[pkgName]
+	if !ok {
+		return ssa.Binding{}, false,
+			ctx.Errorf(ref, "package '%s' not found", pkgName)
+	}
+	b, ok = pkg.Bindings.Get(ref.Name.Name)
+	if !ok {
+		return ssa.Binding{}, false,
+			ctx.Errorf(ref, "undefined variable '%s'", ref.Name)
+	}
+
+	return b, true, nil
+}
+
 // Func returns the current function in the current compilation.
 func (ctx *Codegen) Func() *Func {
 	if len(ctx.Stack) == 0 {

compiler/ast/eval.go

@@ -398,40 +398,9 @@ func (ast *Index) Eval(env *Env, ctx *Codegen, gen *ssa.Generator) (
 func (ast *VariableRef) Eval(env *Env, ctx *Codegen,
 	gen *ssa.Generator) (ssa.Value, bool, error) {
 
-	var b ssa.Binding
-	var ok bool
-
-	// Check if package name is bound to variable.
-	b, ok = env.Get(ast.Name.Package)
-	if ok {
-		// Bound. We are selecting value from its value.
-		val, ok := b.Bound.(*ssa.Value)
-		if !ok || !val.Const {
-			return ssa.Undefined, false, nil
-		}
-		return ssa.Undefined, false, ctx.Errorf(ast,
-			"VariableRef.Eval: select not implemented yet")
-	}
-
-	if len(ast.Name.Package) > 0 {
-		var pkg *Package
-		pkg, ok = ctx.Packages[ast.Name.Package]
-		if !ok {
-			return ssa.Undefined, false, ctx.Errorf(ast,
-				"package '%s' not found", ast.Name.Package)
-		}
-		b, ok = pkg.Bindings.Get(ast.Name.Name)
-	} else {
-		// First check env bindings.
-		b, ok = env.Get(ast.Name.Name)
-		if !ok {
-			// Check names in the current package.
-			b, ok = ctx.Package.Bindings.Get(ast.Name.Name)
-		}
-	}
-	if !ok {
-		return ssa.Undefined, false, ctx.Errorf(ast, "undefined variable '%s'",
-			ast.Name.String())
+	b, ok, err := ctx.LookupVar(env.Bindings, ast)
+	if !ok || err != nil {
+		return ssa.Undefined, ok, err
 	}
 
 	val, ok := b.Bound.(*ssa.Value)
@@ -452,6 +421,9 @@ func (ast *BasicLit) Eval(env *Env, ctx *Codegen, gen *ssa.Generator) (
 func (ast *CompositeLit) Eval(env *Env, ctx *Codegen, gen *ssa.Generator) (
 	ssa.Value, bool, error) {
 
+	// XXX the init values might be short so we must pad them with
+	// zero values so that we create correctly sized values.
+
 	typeInfo, err := ast.Type.Resolve(env, ctx, gen)
 	if err != nil {
 		return ssa.Undefined, false, err