[Assembler] Enable nicer diagnostics for inline assembly.

[sanwou01]

Summary

When a regular SrcMgr is not available, which is the case for inline
assembly, use the InlineSrcMgr to report diagnostics instead of using
the generic report_fatal_error().

[rengolin]

This is simple and makes sense. But all the other inline asm look correlated. Since you marked as dependencies, and phab is not really great to handle deps, can I ask you a favour?

Try to join all inline asm reporting dependencies into a new patch (don't mess up the existing ones), just so we see how it looks like.

At least the squashed patch will give us an overview or what they accomplish. It may even make more sense to commit squashed, in case we need to revert one in between, reverting a single patch is easier than 5. :)

cheers,
--renato

[sanwou01]

Hi Renato,

Squashed patch submitted as D29441 .

Thanks,
Sanne

[sanwou01]

Ready to land as D29441.

lib/MC/MCContext.cpp

 
 //===----------------------------------------------------------------------===//
 // Error Reporting
 //===----------------------------------------------------------------------===//
 
 void MCContext::reportError(SMLoc Loc, const Twine &Msg) {
   HadError = true;
 
-  // If we have a source manager use it. Otherwise just use the generic
-  // report_fatal_error().
-  if (!SrcMgr)
-    report_fatal_error(Msg, false);
-
-  // Use the source manager to print the message.
+  // If we have a source manager use it. Otherwise, try using the inline source
+  // manager.
+  // If that fails, use the generic report_fatal_error().
+  if (SrcMgr)
     SrcMgr->PrintMessage(Loc, SourceMgr::DK_Error, Msg);
+  else if (InlineSrcMgr)
+    InlineSrcMgr->PrintMessage(Loc, SourceMgr::DK_Error, Msg);
+  else
+    report_fatal_error(Msg, false);
 }
 
 void MCContext::reportFatalError(SMLoc Loc, const Twine &Msg) {
   reportError(Loc, Msg);
 
   // If we reached here, we are failing ungracefully. Run the interrupt handlers
   // to make sure any special cleanups get done, in particular that we remove
   // files registered with RemoveFileOnSignal.
   sys::RunInterruptHandlers();
   exit(1);
 }

test/Assembler/inline-asm-diags.ll

+; RUN: not llc -filetype=obj < %s 2>&1 -o /dev/null | FileCheck %s
+
+module asm ".word 0x10"
+module asm ".word -bar"
+
+; CHECK: <inline asm>:2:7: error: expected relocatable expression
+
+module asm ".word -foo"
+; CHECK: <inline asm>:3:7: error: expected relocatable expression