Add warning capabilities in LLVM.

The patch adds a new LLVMContext::diagnose that can be used to communicate to
the front-end, if any, that something of interest happened.
The diagnostics are supported by a new abstraction, the DiagnosticInfo class.
The base class contains the following information:
- The kind of the report: What this is about.
- The severity of the report: How bad this is.

This patch also adds 2 classes:
- DiagnosticInfoInlineAsm: For inline asm reporting. Basically, this diagnostic
will be used to switch to the new diagnostic API for LLVMContext::emitError.
- DiagnosticStackSize: For stack size reporting. Comes as a replacement of the
hard coded warning in PEI.

This patch also features dynamic diagnostic identifiers. In other words plugins
can use this infrastructure for their own diagnostics (for more details, see
getNextAvailablePluginDiagnosticKind).

This patch introduces a new DiagnosticHandlerTy and a new DiagnosticContext in
the LLVMContext that should be set by the front-end to be able to map these
diagnostics in its own system.

http://llvm-reviews.chandlerc.com/D2376
<rdar://problem/15515174>

llvm-svn: 197438

1 files changed, 41 insertions, 0 deletions

diff --git a/llvm/lib/IR/LLVMContext.cpp b/llvm/lib/IR/LLVMContext.cpp
index 883bb9878fa..26541d81684 100644
--- a/llvm/lib/IR/LLVMContext.cpp
+++ b/llvm/lib/IR/LLVMContext.cpp
@@ -17,6 +17,8 @@
 #include "llvm/IR/Constants.h"
 #include "llvm/IR/Instruction.h"
 #include "llvm/IR/Metadata.h"
+#include "llvm/Support/DiagnosticInfo.h"
+#include "llvm/Support/DiagnosticPrinter.h"
 #include "llvm/Support/ManagedStatic.h"
 #include "llvm/Support/SourceMgr.h"
 #include <cctype>
@@ -98,6 +100,20 @@ void *LLVMContext::getInlineAsmDiagnosticContext() const {
   return pImpl->InlineAsmDiagContext;
 }
 
+void LLVMContext::setDiagnosticHandler(DiagnosticHandlerTy DiagnosticHandler,
+                                       void *DiagnosticContext) {
+  pImpl->DiagnosticHandler = DiagnosticHandler;
+  pImpl->DiagnosticContext = DiagnosticContext;
+}
+
+LLVMContext::DiagnosticHandlerTy LLVMContext::getDiagnosticHandler() const {
+  return pImpl->DiagnosticHandler;
+}
+
+void *LLVMContext::getDiagnosticContext() const {
+  return pImpl->DiagnosticContext;
+}
+
 void LLVMContext::emitError(const Twine &ErrorStr) {
   emitError(0U, ErrorStr);
 }
@@ -112,6 +128,31 @@ void LLVMContext::emitError(const Instruction *I, const Twine &ErrorStr) {
   return emitError(LocCookie, ErrorStr);
 }
 
+void LLVMContext::diagnose(const DiagnosticInfo &DI) {
+  // If there is a report handler, use it.
+  if (pImpl->DiagnosticHandler != 0) {
+    pImpl->DiagnosticHandler(DI, pImpl->DiagnosticContext);
+    return;
+  }
+  // Otherwise, print the message with a prefix based on the severity.
+  std::string MsgStorage;
+  raw_string_ostream Stream(MsgStorage);
+  DiagnosticPrinterRawOStream DP(Stream);
+  DI.print(DP);
+  Stream.flush();
+  switch (DI.getSeverity()) {
+  case DS_Error:
+    errs() << "error: " << MsgStorage << "\n";
+    exit(1);
+  case DS_Warning:
+    errs() << "warning: " << MsgStorage << "\n";
+    break;
+  case DS_Note:
+    errs() << "note: " << MsgStorage << "\n";
+    break;
+  }
+}
+
 void LLVMContext::emitError(unsigned LocCookie, const Twine &ErrorStr) {
   // If there is no error handler installed, just print the error and exit.
   if (pImpl->InlineAsmDiagHandler == 0) {