From 73631ee6e2bf47d016ff179796e59176b0cbed3e Mon Sep 17 00:00:00 2001 From: whitequark Date: Tue, 11 Jun 2019 03:54:22 +0000 Subject: [PATCH] back.pysim: check for a clock being added twice. This commit adds a best-effort error for a common mistake of adding a clock driving the same domain twice, such as a result of a copy-paste error. Fixes #27. --- nmigen/back/pysim.py | 5 +++++ nmigen/test/test_sim.py | 7 +++++++ 2 files changed, 12 insertions(+) diff --git a/nmigen/back/pysim.py b/nmigen/back/pysim.py index 530ee7d..fee545a 100644 --- a/nmigen/back/pysim.py +++ b/nmigen/back/pysim.py @@ -366,6 +366,7 @@ class Simulator: self._delta = 0. self._epsilon = 1e-10 self._fastest_clock = self._epsilon + self._all_clocks = set() # {str/domain} self._state = _State() self._processes = set() # {process} @@ -426,6 +427,9 @@ class Simulator: def add_clock(self, period, phase=None, domain="sync"): if self._fastest_clock == self._epsilon or period < self._fastest_clock: self._fastest_clock = period + if domain in self._all_clocks: + raise ValueError("Domain '{}' already has a clock driving it" + .format(domain)) half_period = period / 2 if phase is None: @@ -440,6 +444,7 @@ class Simulator: yield clk.eq(0) yield Delay(half_period) self.add_process(clk_process) + self._all_clocks.add(domain) def __enter__(self): if self._vcd_file: diff --git a/nmigen/test/test_sim.py b/nmigen/test/test_sim.py index ff3986d..52a1f76 100644 --- a/nmigen/test/test_sim.py +++ b/nmigen/test/test_sim.py @@ -388,6 +388,13 @@ class SimulatorIntegrationTestCase(FHDLTestCase): "a generator function"): sim.add_process(1) + def test_add_clock_wrong(self): + with self.assertSimulation(Module()) as sim: + sim.add_clock(1) + with self.assertRaises(ValueError, + msg="Domain 'sync' already has a clock driving it"): + sim.add_clock(1) + def test_eq_signal_unused_wrong(self): self.setUp_lhs_rhs() self.s = Signal() -- 2.30.2