diff options
| -rw-r--r-- | src/glsl/loop_unroll.cpp | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/src/glsl/loop_unroll.cpp b/src/glsl/loop_unroll.cpp index ce795f6cd24..635e1dd99cd 100644 --- a/src/glsl/loop_unroll.cpp +++ b/src/glsl/loop_unroll.cpp @@ -64,6 +64,7 @@ class loop_unroll_count : public ir_hierarchical_visitor { public: int nodes; bool unsupported_variable_indexing; + bool array_indexed_by_induction_var_with_exact_iterations; /* If there are nested loops, the node count will be inaccurate. */ bool nested_loop; @@ -74,6 +75,7 @@ public: nodes = 0; nested_loop = false; unsupported_variable_indexing = false; + array_indexed_by_induction_var_with_exact_iterations = false; run(list); } @@ -112,6 +114,14 @@ public: ir_variable *array = ir->array->variable_referenced(); loop_variable *lv = ls->get(ir->array_index->variable_referenced()); if (array && lv && lv->is_induction_var()) { + /* If an array is indexed by a loop induction variable, and the + * array size is exactly the number of loop iterations, this is + * probably a simple for-loop trying to access each element in + * turn; the application may expect it to be unrolled. + */ + if (int(array->type->length) == ls->limiting_terminator->iterations) + array_indexed_by_induction_var_with_exact_iterations = true; + switch (array->data.mode) { case ir_var_auto: case ir_var_temporary: @@ -314,7 +324,8 @@ loop_unroll_visitor::visit_leave(ir_loop *ir) bool loop_too_large = count.nested_loop || count.nodes * iterations > max_iterations * 5; - if (loop_too_large && !count.unsupported_variable_indexing) + if (loop_too_large && !count.unsupported_variable_indexing && + !count.array_indexed_by_induction_var_with_exact_iterations) return visit_continue; /* Note: the limiting terminator contributes 1 to ls->num_loop_jumps. |