Add support for Verilog-A style legacy pragma protect comments

roife · Jun 22, 2024 · d455173 · d455173
1 parent 4d655ee
commit d455173
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Showing 4 changed files with 103 additions and 0 deletions.
diff --git a/include/slang/parsing/Lexer.h b/include/slang/parsing/Lexer.h
@@ -113,6 +113,7 @@ class SLANG_EXPORT Lexer {
     bool scanUTF8Char(bool alreadyErrored, uint32_t* code, int& computedLen);
     void scanEncodedText(ProtectEncoding encoding, uint32_t expectedBytes, bool singleLine,
                          bool legacyProtectedMode);
+    void scanProtectComment();
 
     template<typename... Args>
     Token create(TokenKind kind, Args&&... args);

diff --git a/source/parsing/Lexer.cpp b/source/parsing/Lexer.cpp
@@ -12,6 +12,7 @@
 
 #include "slang/diagnostics/LexerDiags.h"
 #include "slang/diagnostics/NumericDiags.h"
+#include "slang/diagnostics/PreprocessorDiags.h"
 #include "slang/syntax/SyntaxKind.h"
 #include "slang/text/CharInfo.h"
 #include "slang/text/SourceManager.h"
@@ -23,6 +24,9 @@ static_assert(std::numeric_limits<double>::is_iec559, "SystemVerilog requires IE
 
 static const double BitsPerDecimal = log2(10.0);
 
+static constexpr std::string_view PragmaBeginProtected = "pragma protect begin_protected"sv;
+static constexpr std::string_view PragmaEndProtected = "pragma protect end_protected"sv;
+
 namespace slang::parsing {
 
 using namespace syntax;
@@ -1195,6 +1199,27 @@ void Lexer::scanWhitespace() {
 }
 
 void Lexer::scanLineComment() {
+    if (options.enableLegacyProtect) {
+        // See if we're looking at a pragma protect comment and skip
+        // over it if so.
+        while (peek() == ' ')
+            advance();
+
+        bool found = true;
+        for (char c : PragmaBeginProtected) {
+            if (!consume(c)) {
+                found = false;
+                break;
+            }
+        }
+
+        if (found) {
+            scanProtectComment();
+            addTrivia(TriviaKind::DisabledText);
+            return;
+        }
+    }
+
     bool sawUTF8Error = false;
     while (true) {
         char c = peek();
@@ -1458,6 +1483,36 @@ void Lexer::scanEncodedText(ProtectEncoding encoding, uint32_t expectedBytes, bo
     }
 }
 
+void Lexer::scanProtectComment() {
+    addDiag(diag::ProtectedEnvelope, currentOffset() - PragmaBeginProtected.size());
+
+    while (true) {
+        char c = peek();
+        if (c == '\0' && reallyAtEnd()) {
+            addDiag(diag::RawProtectEOF, currentOffset() - 1);
+            return;
+        }
+
+        advance();
+        if (c == '/' && peek() == '/') {
+            advance();
+            while (peek() == ' ')
+                advance();
+
+            bool found = true;
+            for (char d : PragmaEndProtected) {
+                if (!consume(d)) {
+                    found = false;
+                    break;
+                }
+            }
+
+            if (found)
+                return;
+        }
+    }
+}
+
 template<typename... Args>
 Token Lexer::create(TokenKind kind, Args&&... args) {
     SourceLocation location(bufferId, size_t(marker - originalBegin));

diff --git a/source/syntax/SyntaxPrinter.cpp b/source/syntax/SyntaxPrinter.cpp
@@ -40,6 +40,10 @@ SyntaxPrinter& SyntaxPrinter::print(Trivia trivia) {
                     print(t);
             }
             break;
+        case TriviaKind::DisabledText:
+            if (includeSkipped)
+                append(trivia.getRawText());
+            break;
         case TriviaKind::LineComment:
         case TriviaKind::BlockComment:
             if (!includeComments)

diff --git a/tests/unittests/parsing/PreprocessorTests.cpp b/tests/unittests/parsing/PreprocessorTests.cpp
@@ -2639,3 +2639,46 @@ endmodule
     CHECK(diagnostics[0].code == diag::ProtectedEnvelope);
     CHECK(diagnostics[1].code == diag::ProtectedEnvelope);
 }
+
+TEST_CASE("Verilog-A style pragma protect comments") {
+    auto& text = R"(
+module top_design (a, b, c);
+    bottom inst ();
+//    pragma protect begin_protected
+//pragma protect key_keyowner=Cadence Design Systems.
+//pragma protect key_keyname=CDS_KEY
+//pragma protect key_method=RC5
+//pragma protect key_block
+hjQ2rsuJMpL9F3O43Xx7zf656dz2xxBxdnHC0GvJFJG3Y5HL0dSoPcLMN5Zy6Iq+
+ySMMWcOGkowbtoHVjNn3UdcZFD6NFlWHJpb7KIc8Php8iT1uEZmtwTgDSy64yqLL
+SCaqKffWXhnJ5n/936szbTSvc8vs2ILJYG4FnjIZeYARwKjbofvTgA==
+//pragma protect end_key_block
+//pragma protect digest_block
+uilUH9+52Dwx1U6ajpWVBgZque4=
+//pragma protect end_digest_block
+//pragma protect data_block
+jGZcQn3lBzXvF2kCXy+abmSjUdOfUzPOp7g7dfEzgN96O2ZRQP4aN7kqJOCA9shI
+jcvO6pnBhjaTNlxUJBSbBA==
+//pragma protect end_data_block
+//pragma protect digest_block
+tzEpxTPg7KWB9yMYYlqfoVE3lVk=
+//pragma protect end_digest_block
+//  pragma protect end_protected
+endmodule
+)";
+
+    auto& expected = R"(
+module top_design (a, b, c);
+    bottom inst ();
+endmodule
+)";
+
+    LexerOptions lo;
+    lo.enableLegacyProtect = true;
+
+    std::string result = preprocess(text, lo);
+    CHECK(result == expected);
+
+    REQUIRE(diagnostics.size() == 1);
+    CHECK(diagnostics[0].code == diag::ProtectedEnvelope);
+}