elements = (stack.loop + stack.push_wqm ) * entry_size;
elements += stack.push;
- /* These next three lines are EVERGREEN specific and should
- * be moved to a virtual function when other chipsets are to
- * be supported */
- assert(m_bc.chip_class == EVERGREEN);
- if (type == FC_PUSH_VPM || stack.push > 0) {
- elements += 1;
+ switch (m_bc.chip_class) {
+ case R600:
+ case R700:
+ /* pre-r8xx: if any non-WQM PUSH instruction is invoked, 2 elements on
+ * the stack must be reserved to hold the current active/continue
+ * masks */
+ if (type == FC_PUSH_VPM || stack.push > 0) {
+ elements += 2;
+ }
+ break;
+ case CAYMAN:
+ /* r9xx: any stack operation on empty stack consumes 2 additional
+ * elements */
+ elements += 2;
+ break;
+ case EVERGREEN:
+ /* r8xx+: 2 extra elements are not always required, but one extra
+ * element must be added for each of the following cases:
+ * 1. There is an ALU_ELSE_AFTER instruction at the point of greatest
+ * stack usage.
+ * (Currently we don't use ALU_ELSE_AFTER.)
+ * 2. There are LOOP/WQM frames on the stack when any flavor of non-WQM
+ * PUSH instruction executed.
+ *
+ * NOTE: it seems we also need to reserve additional element in some
+ * other cases, e.g. when we have 4 levels of PUSH_VPM in the shader,
+ * then STACK_SIZE should be 2 instead of 1 */
+ if (type == FC_PUSH_VPM || stack.push > 0) {
+ elements += 1;
+ }
+ break;
+ default:
+ assert(0);
+ break;
}
entry_size = 4;