From 51ffb093b5beeb5e2c687d2bf34b13d246f3fc7d Mon Sep 17 00:00:00 2001 From: Eddie Hung Date: Thu, 22 Aug 2019 16:42:19 -0700 Subject: [PATCH] In sat: 'x' in init attr should not override constant --- passes/sat/sat.cc | 2 ++ tests/sat/initval.v | 4 ++++ tests/sat/initval.ys | 2 +- 3 files changed, 7 insertions(+), 1 deletion(-) diff --git a/passes/sat/sat.cc b/passes/sat/sat.cc index dd56d8c71..bcc690fa3 100644 --- a/passes/sat/sat.cc +++ b/passes/sat/sat.cc @@ -268,6 +268,8 @@ struct SatHelper RTLIL::SigSpec removed_bits; for (int i = 0; i < lhs.size(); i++) { RTLIL::SigSpec bit = lhs.extract(i, 1); + if (bit.is_fully_const() && rhs[i] == State::Sx) + rhs[i] = bit; if (!satgen.initial_state.check_all(bit)) { removed_bits.append(bit); lhs.remove(i, 1); diff --git a/tests/sat/initval.v b/tests/sat/initval.v index 5b661f8d6..d46ccae48 100644 --- a/tests/sat/initval.v +++ b/tests/sat/initval.v @@ -1,6 +1,7 @@ module test(input clk, input [3:0] bar, output [3:0] foo); reg [3:0] foo = 0; reg [3:0] last_bar = 0; + reg [3:0] asdf = 4'b1xxx; always @* foo[1:0] <= bar[1:0]; @@ -11,5 +12,8 @@ module test(input clk, input [3:0] bar, output [3:0] foo); always @(posedge clk) last_bar <= bar; + always @* + asdf[2:0] <= 3'b111; + assert property (foo == {last_bar[3:2], bar[1:0]}); endmodule diff --git a/tests/sat/initval.ys b/tests/sat/initval.ys index 2079d2f34..3d88aa971 100644 --- a/tests/sat/initval.ys +++ b/tests/sat/initval.ys @@ -1,4 +1,4 @@ read_verilog -sv initval.v -proc;; +proc; sat -seq 10 -prove-asserts -- 2.30.2