Support super.new calls (#3789)

src/V3AstNodeOther.h

@@ -550,7 +550,7 @@ private:
     string m_cname;  // C name, for dpiExports
     string m_rtnType;  // void, bool, or other return type
     string m_argTypes;  // Argument types
-    string m_ctorInits;  // Constructor sub-class inits
+    string m_baseCtors;  // Base class constructor
     string m_ifdef;  // #ifdef symbol around this function
     VBoolOrUnknown m_isConst;  // Function is declared const (*this not changed)
     bool m_isStatic : 1;  // Function is static (no need for a 'this' pointer)
@@ -611,7 +611,7 @@ public:
     bool same(const AstNode* samep) const override {
         const AstCFunc* const asamep = static_cast<const AstCFunc*>(samep);
         return ((isTrace() == asamep->isTrace()) && (rtnTypeVoid() == asamep->rtnTypeVoid())
-                && (argTypes() == asamep->argTypes()) && (ctorInits() == asamep->ctorInits())
+                && (argTypes() == asamep->argTypes()) && (baseCtors() == asamep->baseCtors())
                 && isLoose() == asamep->isLoose()
                 && (!(dpiImportPrototype() || dpiExportImpl()) || name() == asamep->name()));
     }
@@ -644,8 +644,8 @@ public:
     void funcPublic(bool flag) { m_funcPublic = flag; }
     void argTypes(const string& str) { m_argTypes = str; }
     string argTypes() const { return m_argTypes; }
-    void ctorInits(const string& str) { m_ctorInits = str; }
-    string ctorInits() const { return m_ctorInits; }
+    void baseCtors(const string& str) { m_baseCtors = str; }
+    string baseCtors() const { return m_baseCtors; }
     void ifdef(const string& str) { m_ifdef = str; }
     string ifdef() const { return m_ifdef; }
     bool isConstructor() const { return m_isConstructor; }

src/V3EmitCFunc.cpp

@@ -422,11 +422,7 @@ void EmitCFunc::emitCCallArgs(const AstNodeCCall* nodep, const string& selfPoint
         puts(nodep->argTypes());
         comma = true;
     }
-    for (AstNode* subnodep = nodep->argsp(); subnodep; subnodep = subnodep->nextp()) {
-        if (comma) puts(", ");
-        iterate(subnodep);
-        comma = true;
-    }
+    putCommaIterateNext(nodep->argsp(), comma);
     puts(")");
 }
 

src/V3EmitCFunc.h

@@ -205,6 +205,13 @@ public:
         m_emitConstInit = true;
         iterate(initp);
     }
+    void putCommaIterateNext(AstNode* nodep, bool comma = false) {
+        for (AstNode* subnodep = nodep; subnodep; subnodep = subnodep->nextp()) {
+            if (comma) puts(", ");
+            iterate(subnodep);
+            comma = true;
+        }
+    }
 
     // VISITORS
     using EmitCConstInit::visit;
@@ -221,11 +228,24 @@ public:
         if (nodep->isInline()) puts("VL_INLINE_OPT ");
         emitCFuncHeader(nodep, m_modp, /* withScope: */ true);
 
-        // TODO perhaps better to have a new AstCCtorInit so we can pass arguments
-        // rather than requiring a string here
-        if (!nodep->ctorInits().empty()) {
+        if (!nodep->baseCtors().empty()) {
             puts(": ");
-            puts(nodep->ctorInits());
+            puts(nodep->baseCtors());
+            puts("(vlSymsp");
+            // Find call to super.new to get the arguments
+            for (AstNode* stmtp = nodep->stmtsp(); stmtp; stmtp = stmtp->nextp()) {
+                AstNode* exprp;
+                if (VN_IS(stmtp, StmtExpr)) {
+                    exprp = VN_CAST(stmtp, StmtExpr)->exprp();
+                } else {
+                    exprp = stmtp;
+                }
+                if (AstCNew* const newRefp = VN_CAST(exprp, CNew)) {
+                    putCommaIterateNext(newRefp->argsp(), true);
+                    break;
+                }
+            }
+            puts(")");
         }
         puts(" {\n");
 
@@ -417,15 +437,13 @@ public:
         iterate(nodep->exprp());
     }
     void visit(AstCNew* nodep) override {
-        bool comma = false;
-        puts("VL_NEW(" + prefixNameProtect(nodep->dtypep()) + ", ");
-        puts("vlSymsp");  // TODO make this part of argsp, and eliminate when unnecessary
-        if (nodep->argsp()) comma = true;
-        for (AstNode* subnodep = nodep->argsp(); subnodep; subnodep = subnodep->nextp()) {
-            if (comma) puts(", ");
-            iterate(subnodep);
-            comma = true;
+        if (VN_IS(nodep->dtypep(), VoidDType)) {
+            // super.new case
+            return;
         }
+        // assignment case
+        puts("VL_NEW(" + prefixNameProtect(nodep->dtypep()) + ", vlSymsp");
+        putCommaIterateNext(nodep->argsp(), true);
         puts(")");
     }
     void visit(AstCMethodHard* nodep) override {

src/V3Task.cpp

@@ -1181,8 +1181,8 @@ private:
             cfuncp->isConstructor(true);
             AstClass* const classp = m_statep->getClassp(nodep);
             if (classp->extendsp()) {
-                cfuncp->ctorInits(EmitCBaseVisitor::prefixNameProtect(classp->extendsp()->classp())
-                                  + "(vlSymsp)");
+                cfuncp->baseCtors(
+                    EmitCBaseVisitor::prefixNameProtect(classp->extendsp()->classp()));
             }
         }
         if (cfuncp->dpiExportImpl()) cfuncp->cname(nodep->cname());

src/V3Width.cpp

@@ -3555,22 +3555,32 @@ private:
 
     void visit(AstNew* nodep) override {
         if (nodep->didWidth()) return;
-        AstClassRefDType* const refp
-            = m_vup ? VN_CAST(m_vup->dtypeNullSkipRefp(), ClassRefDType) : nullptr;
-        if (!refp) {  // e.g. int a = new;
-            nodep->v3error("new() not expected in this context");
-            return;
-        }
-        nodep->dtypep(refp);
+        AstClass* classp = nullptr;
+        if (VN_IS(nodep->backp(), Assign)) {  // assignment case
+            AstClassRefDType* const refp
+                = m_vup ? VN_CAST(m_vup->dtypeNullSkipRefp(), ClassRefDType) : nullptr;
+            if (!refp) {  // e.g. int a = new;
+                nodep->v3error("new() not expected in this context");
+                return;
+            }
+            nodep->dtypep(refp);
 
-        AstClass* const classp = refp->classp();
-        UASSERT_OBJ(classp, nodep, "Unlinked");
-        if (AstNodeFTask* const ftaskp = VN_CAST(classp->findMember("new"), Func)) {
-            nodep->taskp(ftaskp);
-            nodep->classOrPackagep(classp);
-        } else {
-            // Either made explicitly or V3LinkDot made implicitly
-            classp->v3fatalSrc("Can't find class's new");
+            classp = refp->classp();
+            UASSERT_OBJ(classp, nodep, "Unlinked");
+            if (AstNodeFTask* const ftaskp = VN_CAST(classp->findMember("new"), Func)) {
+                nodep->taskp(ftaskp);
+                nodep->classOrPackagep(classp);
+            } else {
+                // Either made explicitly or V3LinkDot made implicitly
+                classp->v3fatalSrc("Can't find class's new");
+            }
+        } else {  // super.new case
+            // in this case class and taskp() should be properly linked in V3LinkDot.cpp during
+            // "super" reference resolution
+            classp = VN_CAST(nodep->classOrPackagep(), Class);
+            UASSERT_OBJ(classp, nodep, "Unlinked classOrPackagep()");
+            UASSERT_OBJ(nodep->taskp(), nodep, "Unlinked taskp()");
+            nodep->dtypeFrom(nodep->taskp());
         }
         if (classp->isVirtual()) {
             nodep->v3error(

test_regress/t/t_class_super_new.pl

@@ -0,0 +1,20 @@
+#!/usr/bin/env perl
+if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); die; }
+# DESCRIPTION: Verilator: Verilog Test driver/expect definition
+#
+# Copyright 2022 by Antmicro Ltd. This program is free software; you
+# can redistribute it and/or modify it under the terms of either the GNU
+# Lesser General Public License Version 3 or the Perl Artistic License
+# Version 2.0.
+# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+
+scenarios(simulator => 1);
+
+compile();
+
+execute(
+    check_finished => 1,
+    );
+
+ok(1);
+1;

test_regress/t/t_class_super_new.v

@@ -0,0 +1,101 @@
+// DESCRIPTION: Verilator: Verilog Test module
+//
+// This file ONLY is placed under the Creative Commons Public Domain, for
+// any use, without warranty, 2022 by Antmicro Ltd.
+// SPDX-License-Identifier: CC0-1.0
+
+`define stop $stop
+`define checkh(gotv,expv) do if ((gotv) !== (expv)) begin $write("%%Error: %s:%0d:  got='h%x exp='h%x\n", `__FILE__,`__LINE__, (gotv), (expv)); `stop; end while(0);
+
+class Foo;
+   int x;
+   function new;
+      this.x = 10;
+   endfunction
+endclass
+
+class Bar extends Foo;
+   function new;
+      super.new;
+   endfunction
+endclass
+
+class BarUnusedArg extends Foo;
+   function new (int a);
+      super.new;
+   endfunction
+endclass
+
+class FooArg;
+   int x;
+   function new (int a);
+      this.x = a;
+   endfunction
+endclass
+
+class BarArg extends FooArg;
+   function new (int a);
+      super.new(a);
+   endfunction
+endclass
+
+class BarExpr extends FooArg;
+   function new (int a, string b);
+      super.new(a + b.len());
+   endfunction
+endclass
+
+class Foo2Args;
+   int x;
+   function new (int a, int b);
+      this.x = a + b;
+   endfunction
+endclass
+
+class Bar2Args extends Foo2Args;
+   function new (int a, int b);
+      super.new(a, b);
+   endfunction
+endclass
+
+module t (/*AUTOARG*/
+   );
+
+   class FooInModule;
+      int x;
+      function new;
+         this.x = 15;
+      endfunction
+   endclass
+
+   class BarInModule extends FooInModule;
+      function new;
+         super.new;
+      endfunction
+   endclass
+
+   Bar bar;
+   BarInModule barInModule;
+   BarUnusedArg barUnusedArg;
+   BarArg barArg;
+   BarExpr barExpr;
+   Bar2Args bar2Args;
+
+   initial begin
+      bar = new;
+      `checkh(bar.x, 10);
+      barInModule = new;
+      `checkh(barInModule.x, 15);
+      barUnusedArg = new(2);
+      `checkh(barUnusedArg.x, 10);
+      barArg = new(2);
+      `checkh(barArg.x, 2);
+      barExpr = new (7, "ABCDEFGHI");
+      `checkh(barExpr.x, 16);
+      bar2Args = new(2, 12);
+      `checkh(bar2Args.x, 14);
+
+      $write("*-* All Finished *-*\n");
+      $finish;
+   end
+endmodule