From 5ccdc23a86978628449ace0058cd3697020b0c94 Mon Sep 17 00:00:00 2001 From: Matt Turner Date: Sun, 7 Sep 2014 00:41:41 -0700 Subject: [PATCH] glsl: Recognize open-coded pow(x, y). pow(x, y) is equivalent to exp(log(x) * y). instructions in affected programs: 578 -> 458 (-20.76%) Reviewed-by: Kenneth Graunke --- src/glsl/opt_algebraic.cpp | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/src/glsl/opt_algebraic.cpp b/src/glsl/opt_algebraic.cpp index 447618f9ef9..0cdb8ecfc0a 100644 --- a/src/glsl/opt_algebraic.cpp +++ b/src/glsl/opt_algebraic.cpp @@ -357,6 +357,20 @@ ir_algebraic_visitor::handle_expression(ir_expression *ir) if (op_expr[0]->operation == ir_unop_log2) { return op_expr[0]->operands[0]; } + + if (!options->EmitNoPow && op_expr[0]->operation == ir_binop_mul) { + for (int log2_pos = 0; log2_pos < 2; log2_pos++) { + ir_expression *log2_expr = + op_expr[0]->operands[log2_pos]->as_expression(); + + if (log2_expr && log2_expr->operation == ir_unop_log2) { + return new(mem_ctx) ir_expression(ir_binop_pow, + ir->type, + log2_expr->operands[0], + op_expr[0]->operands[1 - log2_pos]); + } + } + } break; case ir_unop_log2: -- 2.30.2