From db8fcbbaf940cdf690878f204f17d8bc90a6768e Mon Sep 17 00:00:00 2001 From: Kenneth Graunke Date: Fri, 29 Apr 2016 13:19:33 -0700 Subject: [PATCH] glsl: Avoid excess tree walking when folding ir_dereference_arrays. If an ir_dereference_array has non-constant components, there's no point in trying to evaluate its value (which involves walking down the tree and possibly allocating memory for portions of the subtree which are constant). This also removes convoluted tree walking in opt_constant_folding(), which tries to fold constants while walking up the tree. No need to walk down, then up, then down again. We did this for swizzles and expressions already, but I was lazy back in the day and didn't do this for ir_dereference_array. No change in shader-db. Signed-off-by: Kenneth Graunke Reviewed-by: Ian Romanick --- src/compiler/glsl/opt_constant_folding.cpp | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/src/compiler/glsl/opt_constant_folding.cpp b/src/compiler/glsl/opt_constant_folding.cpp index 0ea53a5ed1b..ee67420adf8 100644 --- a/src/compiler/glsl/opt_constant_folding.cpp +++ b/src/compiler/glsl/opt_constant_folding.cpp @@ -85,6 +85,12 @@ ir_constant_fold(ir_rvalue **rvalue) if (swiz && !swiz->val->as_constant()) return false; + /* Ditto for array dereferences */ + ir_dereference_array *array_ref = (*rvalue)->as_dereference_array(); + if (array_ref && (!array_ref->array->as_constant() || + !array_ref->array_index->as_constant())) + return false; + ir_constant *constant = (*rvalue)->constant_expression_value(); if (constant) { *rvalue = constant; -- 2.30.2