From 17163cf43a6b6eec9aac44f6a4463dda54b8ed68 Mon Sep 17 00:00:00 2001 From: Xiretza Date: Wed, 8 Apr 2020 19:30:47 +0200 Subject: Add flooring modulo operator The $div and $mod cells use truncating division semantics (rounding towards 0), as defined by e.g. Verilog. Another rounding mode, flooring (rounding towards negative infinity), can be used in e.g. VHDL. The new $modfloor cell provides this flooring modulo (also known as "remainder" in several languages, but this name is ambiguous). This commit also fixes the handling of $mod in opt_expr, which was previously optimized as if it was $modfloor. --- passes/tests/test_cell.cc | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'passes/tests') diff --git a/passes/tests/test_cell.cc b/passes/tests/test_cell.cc index cdbe922b2..bc5ff598e 100644 --- a/passes/tests/test_cell.cc +++ b/passes/tests/test_cell.cc @@ -264,7 +264,7 @@ static void create_gold_module(RTLIL::Design *design, RTLIL::IdString cell_type, cell->setPort(ID::Y, wire); } - if (muxdiv && cell_type.in(ID($div), ID($mod))) { + if (muxdiv && cell_type.in(ID($div), ID($mod), ID($modfloor))) { auto b_not_zero = module->ReduceBool(NEW_ID, cell->getPort(ID::B)); auto div_out = module->addWire(NEW_ID, GetSize(cell->getPort(ID::Y))); module->addMux(NEW_ID, RTLIL::SigSpec(0, GetSize(div_out)), div_out, b_not_zero, cell->getPort(ID::Y)); @@ -839,6 +839,7 @@ struct TestCellPass : public Pass { cell_types[ID($mul)] = "ABSY"; cell_types[ID($div)] = "ABSY"; cell_types[ID($mod)] = "ABSY"; + cell_types[ID($modfloor)] = "ABSY"; // cell_types[ID($pow)] = "ABsY"; cell_types[ID($logic_not)] = "ASY"; -- cgit v1.2.3