From 4abc8e695ad0b3b11ae687d776856dd98b56101d Mon Sep 17 00:00:00 2001 From: Clifford Wolf Date: Fri, 8 Nov 2013 04:44:09 +0100 Subject: [PATCH] Implemented const folding of ternary op with undef select --- frontends/ast/simplify.cc | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/frontends/ast/simplify.cc b/frontends/ast/simplify.cc index 5c0130d42..9fa7f558b 100644 --- a/frontends/ast/simplify.cc +++ b/frontends/ast/simplify.cc @@ -1074,6 +1074,14 @@ skip_dynamic_range_lvalue_expansion:; if (choice != NULL && choice->type == AST_CONSTANT) { RTLIL::Const y = choice->bitsAsConst(width_hint, sign_hint); newNode = mkconst_bits(y.bits, sign_hint); + } else if (children[1]->type == AST_CONSTANT && children[2]->type == AST_CONSTANT) { + RTLIL::Const a = children[1]->bitsAsConst(width_hint, sign_hint); + RTLIL::Const b = children[2]->bitsAsConst(width_hint, sign_hint); + assert(a.bits.size() == b.bits.size()); + for (size_t i = 0; i < a.bits.size(); i++) + if (a.bits[i] != b.bits[i]) + a.bits[i] = RTLIL::State::Sx; + newNode = mkconst_bits(a.bits, sign_hint); } } break;