From d46074e0ad62199dadbd7b8e2eca725fc8e807aa Mon Sep 17 00:00:00 2001
From: Wilson Snyder <wsnyder@wsnyder.org>
Date: Sat, 16 Jan 2010 20:14:52 -0500
Subject: [PATCH] CDC: --cdc now implies early exit, to allow eventual
 set_logic_0/1 on sigs

---
 bin/verilator                     |  6 +++---
 src/Verilator.cpp                 | 17 +++++++++++++----
 test_regress/t/t_cdc_async_bad.pl |  2 +-
 3 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/bin/verilator b/bin/verilator
index 75203b6ed..9d9c4d3e8 100755
--- a/bin/verilator
+++ b/bin/verilator
@@ -314,9 +314,9 @@ Specifies C++ without SystemC output mode; see also --sc and --sp.
 =item --cdc
 
 Experimental.  Perform some clock domain crossing checks and issue related
-warnings.  Additional warning information is written to the file
-{prefix}__cdc.txt.  Generally used with --lint-only.  Enables CDCRSTLOGIC
-warning.
+warnings (CDCRSTLOGIC) and then exit; if warnings other than CDC warnings
+are needed make a second run with --lint-only.  Additional warning
+information is also written to the file {prefix}__cdc.txt.
 
 Currently only checks some items that other CDC tools missed; if you have
 interest in adding more traditional CDC checks, please contact the authors.
diff --git a/src/Verilator.cpp b/src/Verilator.cpp
index 587c0a836..867385f4d 100644
--- a/src/Verilator.cpp
+++ b/src/Verilator.cpp
@@ -356,6 +356,8 @@ void process () {
     // Clock domain crossing analysis
     if (v3Global.opt.cdc()) {
 	V3Cdc::cdcAll(v3Global.rootp());
+	V3Error::abortIfErrors();
+	return;
     }
 
     // Reorder assignments in pipelined blocks
@@ -527,6 +529,8 @@ void process () {
 	// Makefile must be after all other emitters
 	V3EmitMk::emitmk(v3Global.rootp());
     }
+
+    // Note early return above when opt.cdc()
 }
 
 //######################################################################
@@ -550,8 +554,11 @@ int main(int argc, char** argv, char** env) {
     if (v3Global.opt.coverage() && !v3Global.opt.systemPerl() && !v3Global.opt.lintOnly()) {
 	v3fatal("Unsupported: Coverage analysis requires --sp output.");
     }
-    if (!v3Global.opt.outFormatOk() && !v3Global.opt.preprocOnly() && !v3Global.opt.lintOnly()) {
-	v3fatal("verilator: Need --cc, --sc, --sp, --lint-only or --E option");
+    if (!v3Global.opt.outFormatOk()
+	&& !v3Global.opt.preprocOnly()
+	&& !v3Global.opt.lintOnly()
+	&& !v3Global.opt.cdc()) {
+	v3fatal("verilator: Need --cc, --sc, --sp, --cdc, --lint-only or --E option");
     }
     // Check environment
     V3Options::getenvSYSTEMC();
@@ -566,6 +573,7 @@ int main(int argc, char** argv, char** env) {
     if (v3Global.opt.skipIdentical()
 	&& !v3Global.opt.preprocOnly()
 	&& !v3Global.opt.lintOnly()
+	&& !v3Global.opt.cdc()
 	&& V3File::checkTimes(v3Global.opt.makeDir()+"/"+v3Global.opt.prefix()+"__verFiles.dat", argString)) {
 	UINFO(1,"--skip-identical: No change to any source files, exiting\n");
 	exit(0);
@@ -593,10 +601,11 @@ int main(int argc, char** argv, char** env) {
     v3Global.rootp()->dumpTreeFile(v3Global.debugFilename("final.tree",99));
     V3Error::abortIfWarnings();
 
-    if (!v3Global.opt.lintOnly() && v3Global.opt.makeDepend()) {
+    if (!v3Global.opt.lintOnly() && !v3Global.opt.cdc()
+	&& v3Global.opt.makeDepend()) {
 	V3File::writeDepend(v3Global.opt.makeDir()+"/"+v3Global.opt.prefix()+"__ver.d");
     }
-    if (!v3Global.opt.lintOnly()
+    if (!v3Global.opt.lintOnly() && !v3Global.opt.cdc()
 	&& (v3Global.opt.skipIdentical() || v3Global.opt.makeDepend())) {
 	V3File::writeTimes(v3Global.opt.makeDir()+"/"+v3Global.opt.prefix()+"__verFiles.dat", argString);
     }
diff --git a/test_regress/t/t_cdc_async_bad.pl b/test_regress/t/t_cdc_async_bad.pl
index ccf4ac704..b3bfd4d88 100755
--- a/test_regress/t/t_cdc_async_bad.pl
+++ b/test_regress/t/t_cdc_async_bad.pl
@@ -8,7 +8,7 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Version 2.0.
 
 compile (
-	 v_flags => ['--cdc --lint-only'],
+	 v_flags => ['--cdc'],
 	 verilator_make_gcc => 0,
 	 fails => 1,
 	 expect=>