diff options
| -rw-r--r-- | src/compiler/glsl/opt_constant_folding.cpp | 9 | ||||
| -rw-r--r-- | src/compiler/glsl/opt_constant_propagation.cpp | 12 |
2 files changed, 21 insertions, 0 deletions
diff --git a/src/compiler/glsl/opt_constant_folding.cpp b/src/compiler/glsl/opt_constant_folding.cpp index ee67420adf8..97dcc7e1acb 100644 --- a/src/compiler/glsl/opt_constant_folding.cpp +++ b/src/compiler/glsl/opt_constant_folding.cpp @@ -91,6 +91,15 @@ ir_constant_fold(ir_rvalue **rvalue) !array_ref->array_index->as_constant())) return false; + /* No constant folding can be performed on variable dereferences. We need + * to explicitly avoid them, as calling constant_expression_value() on a + * variable dereference will return a clone of var->constant_value. This + * would make us propagate the value into the tree, which isn't our job. + */ + ir_dereference_variable *var_ref = (*rvalue)->as_dereference_variable(); + if (var_ref) + return false; + ir_constant *constant = (*rvalue)->constant_expression_value(); if (constant) { *rvalue = constant; diff --git a/src/compiler/glsl/opt_constant_propagation.cpp b/src/compiler/glsl/opt_constant_propagation.cpp index 4b82bd13f9f..fbc22b0e50f 100644 --- a/src/compiler/glsl/opt_constant_propagation.cpp +++ b/src/compiler/glsl/opt_constant_propagation.cpp @@ -138,8 +138,20 @@ public: void ir_constant_propagation_visitor::constant_folding(ir_rvalue **rvalue) { + if (*rvalue == NULL) + return; + if (ir_constant_fold(rvalue)) this->progress = true; + + ir_dereference_variable *var_ref = (*rvalue)->as_dereference_variable(); + if (var_ref) { + ir_constant *constant = var_ref->constant_expression_value(); + if (constant) { + *rvalue = constant; + this->progress = true; + } + } } void |