Fix assertions and wrong output from StmtPrinter's string literal printing.

String literals (including unicode ones) can contain non-Unicode codepoints
if they were written using \x or similar. Write those out using \x, but be
careful that the following character can't be misinterpreted as part of the
\x escape sequence. Convert UTF-16 surrogate pairs back to codepoints before
rendering them.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@154069 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/AST/StmtPrinter.cpp b/lib/AST/StmtPrinter.cpp
index 7ebc1299f07a928fd90744b16b62410ffeff26c6..ef5eefb306cdfc12cdc5c93ccbd2c33e9b5c74b1 100644 (file)
--- a/lib/AST/StmtPrinter.cpp
+++ b/lib/AST/StmtPrinter.cpp
@@ -727,12 +727,40 @@ void StmtPrinter::VisitStringLiteral(StringLiteral *Str) {
   OS << '"';
   static char Hex[] = "0123456789ABCDEF";
 
+  unsigned LastSlashX = Str->getLength();
   for (unsigned I = 0, N = Str->getLength(); I != N; ++I) {
     switch (uint32_t Char = Str->getCodeUnit(I)) {
     default:
-      // FIXME: Is this the best way to print wchar_t?
+      // FIXME: Convert UTF-8 back to codepoints before rendering.
+
+      // Convert UTF-16 surrogate pairs back to codepoints before rendering.
+      // Leave invalid surrogates alone; we'll use \x for those.
+      if (Str->getKind() == StringLiteral::UTF16 && I != N - 1 &&
+          Char >= 0xd800 && Char <= 0xdbff) {
+        uint32_t Trail = Str->getCodeUnit(I + 1);
+        if (Trail >= 0xdc00 && Trail <= 0xdfff) {
+          Char = 0x10000 + ((Char - 0xd800) << 10) + (Trail - 0xdc00);
+          ++I;
+        }
+      }
+
       if (Char > 0xff) {
-        assert(Char <= 0x10ffff && "invalid unicode codepoint");
+        // If this is a wide string, output characters over 0xff using \x
+        // escapes. Otherwise, this is a UTF-16 or UTF-32 string, and Char is a
+        // codepoint: use \x escapes for invalid codepoints.
+        if (Str->getKind() == StringLiteral::Wide ||
+            (Char >= 0xd800 && Char <= 0xdfff) || Char >= 0x110000) {
+          // FIXME: Is this the best way to print wchar_t?
+          OS << "\\x";
+          int Shift = 28;
+          while ((Char >> Shift) == 0)
+            Shift -= 4;
+          for (/**/; Shift >= 0; Shift -= 4)
+            OS << Hex[(Char >> Shift) & 15];
+          LastSlashX = I;
+          break;
+        }
+
         if (Char > 0xffff)
           OS << "\\U00"
              << Hex[(Char >> 20) & 15]
@@ -745,13 +773,26 @@ void StmtPrinter::VisitStringLiteral(StringLiteral *Str) {
            << Hex[(Char >>  0) & 15];
         break;
       }
+
+      // If we used \x... for the previous character, and this character is a
+      // hexadecimal digit, prevent it being slurped as part of the \x.
+      if (LastSlashX + 1 == I) {
+        switch (Char) {
+          case '0': case '1': case '2': case '3': case '4':
+          case '5': case '6': case '7': case '8': case '9':
+          case 'a': case 'b': case 'c': case 'd': case 'e': case 'f':
+          case 'A': case 'B': case 'C': case 'D': case 'E': case 'F':
+            OS << "\"\"";
+        }
+      }
+
       if (Char <= 0xff && isprint(Char))
         OS << (char)Char;
       else  // Output anything hard as an octal escape.
         OS << '\\'
-        << (char)('0'+ ((Char >> 6) & 7))
-        << (char)('0'+ ((Char >> 3) & 7))
-        << (char)('0'+ ((Char >> 0) & 7));
+           << (char)('0' + ((Char >> 6) & 7))
+           << (char)('0' + ((Char >> 3) & 7))
+           << (char)('0' + ((Char >> 0) & 7));
       break;
     // Handle some common non-printable cases to make dumps prettier.
     case '\\': OS << "\\\\"; break;

diff --git a/test/SemaCXX/constexpr-printing.cpp b/test/SemaCXX/constexpr-printing.cpp
index 4e5bc429dbdd5b1f2a5a6a3c5d95809c38a28cc1..fc0cce25eb85013ff5c83bdee440a089b7f669b1 100644 (file)
--- a/test/SemaCXX/constexpr-printing.cpp
+++ b/test/SemaCXX/constexpr-printing.cpp
@@ -85,8 +85,8 @@ constexpr char16_t c16 = get(u"test\0\\\"\t\a\b\234\u1234"); // \
   expected-error {{}} expected-note {{u"test\000\\\"\t\a\b\234\u1234"}}
 constexpr char32_t c32 = get(U"test\0\\\"\t\a\b\234\u1234\U0010ffff"); // \
   expected-error {{}} expected-note {{U"test\000\\\"\t\a\b\234\u1234\U0010FFFF"}}
-constexpr wchar_t wc = get(L"test\0\\\"\t\a\b\234\u1234"); // \
-  expected-error {{}} expected-note {{L"test\000\\\"\t\a\b\234\u1234"}}
+constexpr wchar_t wc = get(L"test\0\\\"\t\a\b\234\u1234\xffffffff"); // \
+  expected-error {{}} expected-note {{L"test\000\\\"\t\a\b\234\x1234\xFFFFFFFF"}}
 
 constexpr char32_t c32_err = get(U"\U00110000"); // expected-error {{invalid universal character}}
 

diff --git a/test/SemaCXX/static-assert.cpp b/test/SemaCXX/static-assert.cpp
index 2b44e81d3e6c4793e03bdccf6080c6da4dab0a7c..68ef0183e252948d7a559b54255d3fc58c53bd6e 100644 (file)
--- a/test/SemaCXX/static-assert.cpp
+++ b/test/SemaCXX/static-assert.cpp
@@ -27,3 +27,10 @@ template<typename T> struct S {
 
 S<char> s1; // expected-note {{in instantiation of template class 'S<char>' requested here}}
 S<int> s2;
+
+static_assert(false, L"\xFFFFFFFF"); // expected-error {{static_assert failed L"\xFFFFFFFF"}}
+static_assert(false, u"\U000317FF"); // expected-error {{static_assert failed u"\U000317FF"}}
+// FIXME: render this as u8"\u03A9"
+static_assert(false, u8"Ω"); // expected-error {{static_assert failed u8"\316\251"}}
+static_assert(false, L"\u1234"); // expected-error {{static_assert failed L"\x1234"}}
+static_assert(false, L"\x1ff" "0\x123" "fx\xfffff" "goop"); // expected-error {{static_assert failed L"\x1FF""0\x123""fx\xFFFFFgoop"}}