[cppia] Fix *= with boxed numbers in jit (#1259)

* [cppia] Fix *= with boxed numbers in jit

In genSetter, if ioValue is a boxed int/float, then we cannot pass it
directly into compiler->mult. We need to perform a conversion into a
float.

This is now closer to how aoSub is handled.

* [tests] Add regression test for cppia jit *= bug

Author: tobil4sk

src/hx/cppia/Cppia.cpp

@@ -3667,8 +3667,10 @@ void genSetter(CppiaCompiler *compiler, const JitVal &ioValue, ExprType exprType
                compiler->mult(ioValue, sJitTempF0, ioValue,true);
             else
             {
-               compiler->mult(sJitTempF0, sJitTempF0, ioValue,true);
-               compiler->convert(sJitTempF0, etFloat, ioValue, exprType );
+               JitTemp fval(compiler, jtFloat);
+               compiler->convert(ioValue, exprType, fval, etFloat);
+               compiler->mult(sJitTempF0, sJitTempF0, fval, true);
+               compiler->convert(sJitTempF0, etFloat, ioValue, exprType);
             }
          }
          break;

test/cppia/Client.hx

@@ -189,6 +189,14 @@ class Client
          default:
       }
 
+      // regression test for #926
+      var x:Dynamic = 3;
+      x *= 5;
+      if (x != 15) {
+         Common.status = 'Failed regression test for #926. x: $x';
+         return;
+      }
+
       final extending = new ClientExtendedExtendedRoot();
 
       extending.addValue();