Hide the concept of diagnostic levels from lex, parse and sema

The compilation pipeline doesn't actually need to know about the high-level
concept of diagnostic mappings, and hiding the final computed level presents
several simplifications and other potential benefits.

The only exceptions are opportunistic checks to see whether expensive code
paths can be avoided for diagnostics that are guaranteed to be ignored at a
certain SourceLocation.

This commit formalizes that invariant by introducing and using
DiagnosticsEngine::isIgnored() in place of individual level checks throughout
lex, parse and sema.

llvm-svn: 211005

1 files changed, 3 insertions, 6 deletions

diff --git a/clang/lib/Lex/Lexer.cpp b/clang/lib/Lex/Lexer.cpp
index 21b51e13cb9..6f6b50b246d 100644
--- a/clang/lib/Lex/Lexer.cpp
+++ b/clang/lib/Lex/Lexer.cpp
@@ -1399,8 +1399,7 @@ static inline CharSourceRange makeCharRange(Lexer &L, const char *Begin,
 static void maybeDiagnoseIDCharCompat(DiagnosticsEngine &Diags, uint32_t C,
                                       CharSourceRange Range, bool IsFirst) {
   // Check C99 compatibility.
-  if (Diags.getDiagnosticLevel(diag::warn_c99_compat_unicode_id,
-                               Range.getBegin()) > DiagnosticsEngine::Ignored) {
+  if (!Diags.isIgnored(diag::warn_c99_compat_unicode_id, Range.getBegin())) {
     enum {
       CannotAppearInIdentifier = 0,
       CannotStartIdentifier
@@ -1422,8 +1421,7 @@ static void maybeDiagnoseIDCharCompat(DiagnosticsEngine &Diags, uint32_t C,
   }
 
   // Check C++98 compatibility.
-  if (Diags.getDiagnosticLevel(diag::warn_cxx98_compat_unicode_id,
-                               Range.getBegin()) > DiagnosticsEngine::Ignored) {
+  if (!Diags.isIgnored(diag::warn_cxx98_compat_unicode_id, Range.getBegin())) {
     static const llvm::sys::UnicodeCharSet CXX03AllowedIDChars(
         CXX03AllowedIDCharRanges);
     if (!CXX03AllowedIDChars.contains(C)) {
@@ -2522,8 +2520,7 @@ bool Lexer::LexEndOfFile(Token &Result, const char *CurPtr) {
       // C++11 [lex.phases] 2.2 p2
       // Prefer the C++98 pedantic compatibility warning over the generic,
       // non-extension, user-requested "missing newline at EOF" warning.
-      if (Diags.getDiagnosticLevel(diag::warn_cxx98_compat_no_newline_eof,
-                                   EndLoc) != DiagnosticsEngine::Ignored) {
+      if (!Diags.isIgnored(diag::warn_cxx98_compat_no_newline_eof, EndLoc)) {
         DiagID = diag::warn_cxx98_compat_no_newline_eof;
       } else {
         DiagID = diag::warn_no_newline_eof;