Add backend dignostic printer for unsupported features

Re-commit of r258950 after fixing layering violation.

Add backend dignostic printer for unsupported features

The related LLVM patch adds a backend diagnostic type for reporting
unsupported features, this adds a printer for them to clang.

In the case where debug location information is not available, I've
changed the printer to report the location as the first line of the
function, rather than the closing brace, as the latter does not give the
user any information. This also affects optimisation remarks.

Differential Revision: http://reviews.llvm.org/D16591

llvm-svn: 259036

1 files changed, 65 insertions, 11 deletions

diff --git a/clang/lib/CodeGen/CodeGenAction.cpp b/clang/lib/CodeGen/CodeGenAction.cpp
index f8ae031..b8352781 100644
--- a/clang/lib/CodeGen/CodeGenAction.cpp
+++ b/clang/lib/CodeGen/CodeGenAction.cpp
@@ -23,6 +23,7 @@
 #include "clang/Lex/Preprocessor.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/Bitcode/ReaderWriter.h"
+#include "llvm/CodeGen/DiagnosticInfoCodeGen.h"
 #include "llvm/IR/DebugInfo.h"
 #include "llvm/IR/DiagnosticInfo.h"
 #include "llvm/IR/DiagnosticPrinter.h"
@@ -242,6 +243,13 @@ namespace clang {
       ((BackendConsumer *)Context)->DiagnosticHandlerImpl(DI);
     }
 
+    /// Get the best possible source location to represent a diagnostic that
+    /// may have associated debug info.
+    const FullSourceLoc
+    getBestLocationFromDebugLoc(const llvm::DiagnosticInfoWithDebugLocBase &D,
+                                bool &BadDebugInfo, StringRef &Filename,
+                                unsigned &Line, unsigned &Column) const;
+
     void InlineAsmDiagHandler2(const llvm::SMDiagnostic &,
                                SourceLocation LocCookie);
 
@@ -254,6 +262,8 @@ namespace clang {
     /// \return True if the diagnostic has been successfully reported, false
     /// otherwise.
     bool StackSizeDiagHandler(const llvm::DiagnosticInfoStackSize &D);
+    /// \brief Specialized handler for unsupported backend feature diagnostic.
+    void UnsupportedDiagHandler(const llvm::DiagnosticInfoUnsupported &D);
     /// \brief Specialized handlers for optimization remarks.
     /// Note that these handlers only accept remarks and they always handle
     /// them.
@@ -439,16 +449,11 @@ BackendConsumer::StackSizeDiagHandler(const llvm::DiagnosticInfoStackSize &D) {
   return false;
 }
 
-void BackendConsumer::EmitOptimizationMessage(
-    const llvm::DiagnosticInfoOptimizationBase &D, unsigned DiagID) {
-  // We only support warnings and remarks.
-  assert(D.getSeverity() == llvm::DS_Remark ||
-         D.getSeverity() == llvm::DS_Warning);
-
+const FullSourceLoc BackendConsumer::getBestLocationFromDebugLoc(
+    const llvm::DiagnosticInfoWithDebugLocBase &D, bool &BadDebugInfo, StringRef &Filename,
+                                unsigned &Line, unsigned &Column) const {
   SourceManager &SourceMgr = Context->getSourceManager();
   FileManager &FileMgr = SourceMgr.getFileManager();
-  StringRef Filename;
-  unsigned Line, Column;
   SourceLocation DILoc;
 
   if (D.isLocationAvailable()) {
@@ -459,6 +464,7 @@ void BackendConsumer::EmitOptimizationMessage(
       // source manager, so pass 1 if Column is not set.
       DILoc = SourceMgr.translateFileLineCol(FE, Line, Column ? Column : 1);
     }
+    BadDebugInfo = DILoc.isInvalid();
   }
 
   // If a location isn't available, try to approximate it using the associated
@@ -467,18 +473,63 @@ void BackendConsumer::EmitOptimizationMessage(
   FullSourceLoc Loc(DILoc, SourceMgr);
   if (Loc.isInvalid())
     if (const Decl *FD = Gen->GetDeclForMangledName(D.getFunction().getName()))
-      Loc = FD->getASTContext().getFullLoc(FD->getBodyRBrace());
+      Loc = FD->getASTContext().getFullLoc(FD->getLocation());
+
+  if (DILoc.isInvalid() && D.isLocationAvailable())
+    // If we were not able to translate the file:line:col information
+    // back to a SourceLocation, at least emit a note stating that
+    // we could not translate this location. This can happen in the
+    // case of #line directives.
+    Diags.Report(Loc, diag::note_fe_backend_invalid_loc)
+        << Filename << Line;
+
+  return Loc;
+}
+
+void BackendConsumer::UnsupportedDiagHandler(
+    const llvm::DiagnosticInfoUnsupported &D) {
+  // We only support errors.
+  assert(D.getSeverity() == llvm::DS_Error);
+
+  StringRef Filename;
+  unsigned Line, Column;
+  bool BadDebugInfo;
+  FullSourceLoc Loc = getBestLocationFromDebugLoc(D, BadDebugInfo, Filename,
+      Line, Column);
+
+  Diags.Report(Loc, diag::err_fe_backend_unsupported) << D.getMessage().str();
+
+  if (BadDebugInfo)
+    // If we were not able to translate the file:line:col information
+    // back to a SourceLocation, at least emit a note stating that
+    // we could not translate this location. This can happen in the
+    // case of #line directives.
+    Diags.Report(Loc, diag::note_fe_backend_invalid_loc)
+        << Filename << Line << Column;
+}
+
+void BackendConsumer::EmitOptimizationMessage(
+    const llvm::DiagnosticInfoOptimizationBase &D, unsigned DiagID) {
+  // We only support warnings and remarks.
+  assert(D.getSeverity() == llvm::DS_Remark ||
+         D.getSeverity() == llvm::DS_Warning);
+
+  StringRef Filename;
+  unsigned Line, Column;
+  bool BadDebugInfo = false;
+  FullSourceLoc Loc = getBestLocationFromDebugLoc(D, BadDebugInfo, Filename,
+      Line, Column);
 
   Diags.Report(Loc, DiagID)
       << AddFlagValue(D.getPassName() ? D.getPassName() : "")
       << D.getMsg().str();
 
-  if (DILoc.isInvalid() && D.isLocationAvailable())
+  if (BadDebugInfo)
     // If we were not able to translate the file:line:col information
     // back to a SourceLocation, at least emit a note stating that
     // we could not translate this location. This can happen in the
     // case of #line directives.
-    Diags.Report(Loc, diag::note_fe_backend_optimization_remark_invalid_loc)
+    Diags.Report(Loc, diag::note_fe_backend_invalid_loc)
         << Filename << Line << Column;
 }
 
@@ -603,6 +654,9 @@ void BackendConsumer::DiagnosticHandlerImpl(const DiagnosticInfo &DI) {
     // handler.
     OptimizationFailureHandler(cast<DiagnosticInfoOptimizationFailure>(DI));
     return;
+  case llvm::DK_Unsupported:
+    UnsupportedDiagHandler(cast<DiagnosticInfoUnsupported>(DI));
+    return;
   default:
     // Plugin IDs are not bound to any value as they are set dynamically.
     ComputeDiagRemarkID(Severity, backend_plugin, DiagID);