Add --waiver-multiline for context-sensitive --waiver-output.

src/V3Waiver.cpp

@@ -19,21 +19,58 @@
 #include "V3Waiver.h"
 
 #include "V3File.h"
+#include "V3Global.h"
 #include "V3Options.h"
 
 #include <memory>
 #include <sstream>
 
-void V3Waiver::addEntry(V3ErrorCode errorCode, const std::string& filename, const std::string& str)
+void V3Waiver::addEntry(V3ErrorCode errorCode, const std::string& filename, const std::string& msg)
     VL_MT_SAFE_EXCLUDES(s_mutex) {
     if (filename == V3Options::getStdPackagePath()) return;
     const V3LockGuard lock{s_mutex};
+
+    string trimmsg = msg;
+    if (!v3Global.opt.waiverMultiline()) {
+        const size_t pos = trimmsg.find('\n');
+        trimmsg = trimmsg.substr(0, pos);
+        if (pos != std::string::npos) trimmsg += '*';
+    }
+    {  // Remove line numbers and context "\n [0-9] | ", "\n  ^[~]+"
+        string result;
+        for (const char* cp = trimmsg.c_str(); *cp; cp = *cp ? cp + 1 : cp) {
+            while (*cp == ' ' || isdigit(*cp)) ++cp;
+            if (*cp == '|') ++cp;
+            // ^~~~~
+            while (*cp == ' ' || *cp == '^') ++cp;
+            while (*cp == '~') ++cp;
+            while (*cp && *cp != '\n') result += *cp++;
+            while (*cp == '\n') result += *cp++;
+        }
+        trimmsg = result;
+    }
+    trimmsg += '*';
+    {  // "\n"->"*", " *"->"*", "* "->"*"
+        string result;
+        string add;
+        result.reserve(trimmsg.size());
+        for (const char& c : trimmsg) {
+            if (c == '*' || !std::isprint(c)) {
+                add = "*";
+            } else if (c == ' ') {
+                if (add != "*") add += c;
+            } else {
+                result += add + c;
+                add = "";
+            }
+        }
+        result += add;
+        trimmsg = result;
+    }
+
     std::stringstream entry;
-    const size_t pos = str.find('\n');
     entry << "lint_off -rule " << errorCode.ascii() << " -file \"*" << filename << "\" -match \""
-          << str.substr(0, pos);
-    if (pos != std::string::npos) entry << "*";
-    entry << "\"";
+          << trimmsg << "\"";
     s_waiverList.push_back(entry.str());
 }
 
@@ -46,9 +83,9 @@ void V3Waiver::write(const std::string& filename) VL_MT_SAFE_EXCLUDES(s_mutex) {
 
     *ofp << "`verilator_config\n\n";
 
-    *ofp << "// Below you find suggested waivers. You have three options:\n";
-    *ofp << "//   1. Fix the reason for the linter warning\n";
-    *ofp << "//   2. Keep the waiver permanently if you are sure this is okay\n";
+    *ofp << "// Below are suggested waivers. You have three options:\n";
+    *ofp << "//   1. Fix the reason for the linter warning in the Verilog sources\n";
+    *ofp << "//   2. Keep the waiver permanently if you are sure it is okay\n";
     *ofp << "//   3. Keep the waiver temporarily to suppress the output\n\n";
 
     const V3LockGuard lock{s_mutex};