From fc84f230011b5a2eab1eefc319e8646b3ca2f657 Mon Sep 17 00:00:00 2001 From: whitequark Date: Mon, 19 Jul 2021 16:20:49 +0000 Subject: [PATCH] cxxrtl: escape colon in variable names in VCD writer. The following VCD file crashes GTKWave's VCD loader: $var wire 1 ! x:1 $end $enddefinitions $end In practice, a colon can be a part of a variable name that is translated from a Verilog function, something like: update$func$.../hdl/hazard3_csr.v:350$2534.$result --- backends/cxxrtl/cxxrtl_vcd.h | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/backends/cxxrtl/cxxrtl_vcd.h b/backends/cxxrtl/cxxrtl_vcd.h index 3f40a8d12..b76922bbd 100644 --- a/backends/cxxrtl/cxxrtl_vcd.h +++ b/backends/cxxrtl/cxxrtl_vcd.h @@ -69,12 +69,25 @@ class vcd_writer { } while (ident != 0); } + void emit_name(const std::string &name) { + for (char c : name) { + if (c == ':') { + // Due to a bug, GTKWave cannot parse a colon in the variable name, causing the VCD file + // to be unreadable. It cannot be escaped either, so replace it with the sideways colon. + buffer += ".."; + } else { + buffer += c; + } + } + } + void emit_var(const variable &var, const std::string &type, const std::string &name, size_t lsb_at, bool multipart) { assert(!streaming); buffer += "$var " + type + " " + std::to_string(var.width) + " "; emit_ident(var.ident); - buffer += " " + name; + buffer += " "; + emit_name(name); if (multipart || name.back() == ']' || lsb_at != 0) { if (var.width == 1) buffer += " [" + std::to_string(lsb_at) + "]"; -- 2.30.2