shader: Add break/continue

internal/shader/stmt.go

@@ -391,6 +391,21 @@ func (cs *compileState) parseStmt(block *block, stmt ast.Stmt, inParams []variab
 			Type: shaderir.Return,
 		})
 
+	case *ast.BranchStmt:
+		switch stmt.Tok {
+		case token.BREAK:
+			stmts = append(stmts, shaderir.Stmt{
+				Type: shaderir.Break,
+			})
+		case token.CONTINUE:
+			stmts = append(stmts, shaderir.Stmt{
+				Type: shaderir.Continue,
+			})
+		default:
+			cs.addError(stmt.Pos(), fmt.Sprintf("invalid token: %s", stmt.Tok))
+			return nil, false
+		}
+
 	case *ast.ExprStmt:
 		exprs, _, ss, ok := cs.parseExpr(block, stmt.X)
 		if !ok {

internal/shader/testdata/for2.expected.vs

@@ -0,0 +1,20 @@
+void F0(out vec2 l0) {
+	vec2 l1 = vec2(0);
+	vec2 l3 = vec2(0);
+	l1 = vec2(0.0);
+	for (int l2 = 0; l2 < 100; l2++) {
+		(l1).x = ((l1).x) + (l2);
+		if (((l1).x) >= (100.0)) {
+			break;
+		}
+	}
+	l3 = vec2(0.0);
+	for (float l4 = 10.0; l4 >= 0.0; l4 -= 2.0) {
+		if (((l3).x) < (100.0)) {
+			continue;
+		}
+		(l3).x = ((l3).x) + (l4);
+	}
+	l0 = l1;
+	return;
+}

internal/shader/testdata/for2.go

@@ -0,0 +1,19 @@
+package main
+
+func Foo() vec2 {
+	v := vec2(0)
+	for i := 0; i < 100; i++ {
+		v.x += i
+		if v.x >= 100 {
+			break
+		}
+	}
+	v2 := vec2(0)
+	for i := 10.0; i >= 0; i -= 2 {
+		if v2.x < 100 {
+			continue
+		}
+		v2.x += i
+	}
+	return v
+}