glsl: Add a helper constructor for expressions that works out result type.

This doesn't cover all expressions or all operand types, but it will
complain if you overreach and it allows for much greater slack on the
programmer's part.

src/glsl/ir.cpp

@@ -231,6 +231,108 @@ ir_expression::ir_expression(int op, const struct glsl_type *type,
    this->operands[3] = op3;
 }
 
+ir_expression::ir_expression(int op, ir_rvalue *op0)
+{
+   this->ir_type = ir_type_expression;
+
+   this->operation = ir_expression_operation(op);
+   this->operands[0] = op0;
+   this->operands[1] = NULL;
+   this->operands[2] = NULL;
+   this->operands[3] = NULL;
+
+   assert(op <= ir_last_unop);
+
+   switch (this->operation) {
+   case ir_unop_bit_not:
+   case ir_unop_logic_not:
+   case ir_unop_neg:
+   case ir_unop_abs:
+   case ir_unop_sign:
+   case ir_unop_rcp:
+   case ir_unop_rsq:
+   case ir_unop_sqrt:
+   case ir_unop_exp:
+   case ir_unop_log:
+   case ir_unop_exp2:
+   case ir_unop_log2:
+   case ir_unop_trunc:
+   case ir_unop_ceil:
+   case ir_unop_floor:
+   case ir_unop_fract:
+   case ir_unop_round_even:
+   case ir_unop_cos:
+   case ir_unop_dFdx:
+   case ir_unop_dFdy:
+      this->type = op0->type;
+      break;
+
+   case ir_unop_any:
+      this->type = glsl_type::bool_type;
+      break;
+
+   default:
+      assert(!"not reached: missing automatic type setup for ir_expression");
+      this->type = op0->type;
+      break;
+   }
+}
+
+ir_expression::ir_expression(int op, ir_rvalue *op0, ir_rvalue *op1)
+{
+   this->ir_type = ir_type_expression;
+
+   this->operation = ir_expression_operation(op);
+   this->operands[0] = op0;
+   this->operands[1] = op1;
+   this->operands[2] = NULL;
+   this->operands[3] = NULL;
+
+   assert(op > ir_last_unop);
+
+   switch (this->operation) {
+   case ir_binop_all_equal:
+   case ir_binop_any_nequal:
+      this->type = glsl_type::bool_type;
+      break;
+
+   case ir_binop_add:
+   case ir_binop_sub:
+   case ir_binop_min:
+   case ir_binop_max:
+   case ir_binop_pow:
+   case ir_binop_mul:
+      if (op0->type->is_scalar()) {
+	 this->type = op1->type;
+      } else if (op1->type->is_scalar()) {
+	 this->type = op0->type;
+      } else {
+	 /* FINISHME: matrix types */
+	 assert(!op0->type->is_matrix() && !op1->type->is_matrix());
+	 assert(op0->type == op1->type);
+	 this->type = op0->type;
+      }
+      break;
+
+   case ir_binop_logic_and:
+   case ir_binop_logic_or:
+      if (op0->type->is_scalar()) {
+	 this->type = op1->type;
+      } else if (op1->type->is_scalar()) {
+	 this->type = op0->type;
+      }
+      break;
+
+   case ir_binop_dot:
+      this->type = glsl_type::float_type;
+      break;
+
+   default:
+      assert(!"not reached: missing automatic type setup for ir_expression");
+      this->type = glsl_type::float_type;
+   }
+}
+
 unsigned int
 ir_expression::get_num_operands(ir_expression_operation op)
 {

src/glsl/ir.h

@@ -842,12 +842,14 @@ public:
     * Constructor for unary operation expressions
     */
    ir_expression(int op, const struct glsl_type *type, ir_rvalue *);
+   ir_expression(int op, ir_rvalue *);
 
    /**
     * Constructor for binary operation expressions
     */
    ir_expression(int op, const struct glsl_type *type,
 		 ir_rvalue *, ir_rvalue *);
+   ir_expression(int op, ir_rvalue *op0, ir_rvalue *op1);
 
    /**
     * Constructor for quad operator expressions