Keep high-level intermediate representation for IR::BINOPs.

That is, keep binary expressions in HIR, this will make constant
folding more effective. Also, the register allocator for
expression-trees used in the V4 compiler will do a better job.

Change-Id: I2d5eea08ecd9c8d6f3aa21f1fd674a691ef9e1b0
Reviewed-by: Michael Brasser <michael.brasser@nokia.com>

2 files changed, 17 insertions, 24 deletions

diff --git a/src/qml/qml/v4/qv4compiler.cpp b/src/qml/qml/v4/qv4compiler.cpp
index f8fe3b4b57..608368afc2 100644
--- a/src/qml/qml/v4/qv4compiler.cpp
+++ b/src/qml/qml/v4/qv4compiler.cpp
@@ -696,29 +696,20 @@ quint8 QV4CompilerPrivate::instructionOpcode(IR::Binop *e)
 
 void QV4CompilerPrivate::visitBinop(IR::Binop *e)
 {
+    if (e->type == IR::InvalidType) {
+        discard();
+        return;
+    }
+
     int left = currentReg;
     int right = currentReg + 1; 
 
-    if (e->left->asTemp() && e->type != IR::StringType)  // Not sure if the e->type != String test is needed
-        left = e->left->asTemp()->index;
-    else
-        traceExpression(e->left, left);
+    traceExpression(e->left, left);
+    traceExpression(e->right, right);
 
-    if (IR::Temp *t = e->right->asTemp())
-        right = t->index;
-    else
-        traceExpression(e->right, right);
-
-    if (e->left->type != e->right->type) {
-        if (qmlVerboseCompiler())
-            qWarning().nospace() << "invalid operands to binary operator " << IR::binaryOperator(e->op)
-                                 << "(`" << IR::binaryOperator(e->left->type)
-                                 << "' and `"
-                                 << IR::binaryOperator(e->right->type)
-                                 << "'";
-        discard();
-        return;
-    }
+    // At this point it is possible that the type of the
+    // subexpressions is different. This can happen because
+    // we keep BINOP expressions in HIR.
 
     switch (e->op) {
     case IR::OpInvalid:
diff --git a/src/qml/qml/v4/qv4irbuilder.cpp b/src/qml/qml/v4/qv4irbuilder.cpp
index b382c262a8..36e88e5276 100644
--- a/src/qml/qml/v4/qv4irbuilder.cpp
+++ b/src/qml/qml/v4/qv4irbuilder.cpp
@@ -823,16 +823,18 @@ bool QV4IRBuilder::visit(AST::NotExpression *ast)
 void QV4IRBuilder::binop(AST::BinaryExpression *ast, ExprResult left, ExprResult right)
 {
     if (IR::Type t = maxType(left.type(), right.type())) {
-        implicitCvt(left, t);
-        implicitCvt(right, t);
+        if (!left->asConst() && !right->asConst()) {
+            // the implicit conversions are needed only
+            // when compiling non-constant expressions.
+            implicitCvt(left, t);
+            implicitCvt(right, t);
+        }
 
         if (_expr.hint == ExprResult::cx) {
             _expr.format = ExprResult::cx;
             _block->CJUMP(_block->BINOP(IR::binaryOperator(ast->op), left, right), _expr.iftrue, _expr.iffalse);
         } else {
-            IR::Expr *code = _block->BINOP(IR::binaryOperator(ast->op), left, right);
-            _expr.code = _block->TEMP(code->type);
-            _block->MOVE(_expr.code, code);
+            _expr.code = _block->BINOP(IR::binaryOperator(ast->op), left, right);
         }
     }
 }