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Diffstat (limited to 'codegen/expression.go')
-rw-r--r--codegen/expression.go41
1 files changed, 41 insertions, 0 deletions
diff --git a/codegen/expression.go b/codegen/expression.go
new file mode 100644
index 0000000..b73f4da
--- /dev/null
+++ b/codegen/expression.go
@@ -0,0 +1,41 @@
+package codegen
+
+import (
+ "fmt"
+ "reflect"
+
+ "github.com/gnolang/parscan/parser"
+ "github.com/gnolang/parscan/vm1"
+)
+
+func postCallExpr(x extNode) error {
+ switch x.Child[0].Kind {
+ case parser.Ident:
+ var numOut int
+ s, _, ok := x.getSym(x.Child[0].Content(), "")
+ if !ok {
+ return fmt.Errorf("invalid symbol %s", x.Child[0].Content())
+ }
+ if i, ok := x.codeIndex(s); ok {
+ // Internal call is always relative to instruction pointer.
+ x.Emit(x.Node, vm1.Call, int64(i-len(x.Code)))
+ } else {
+ // External call, using absolute addr in symtable.
+ x.Emit(x.Node, vm1.CallX, int64(len(x.Child[1].Child)))
+ numOut = reflect.TypeOf(x.Data[s.index]).NumOut()
+ }
+ if !usedRet(x.anc) {
+ x.Emit(x.Node, vm1.Pop, int64(numOut))
+ }
+ }
+ return nil
+}
+
+func usedRet(n *parser.Node) bool {
+ switch n.Kind {
+ case parser.Undefined, parser.StmtBloc:
+ return false
+ default:
+ return true
+ }
+}