[Assembler] Enable nicer diagnostics for inline assembly.
Fixed test.
Summary:
Enables source location in diagnostic messages from the backend.
This is after parsing, during finalization. This requires the
SourceMgr, the inline assembly string buffer, and DiagInfo to still
be alive after EmitInlineAsm returns.
This patch creates a single SourceMgr for inline assembly inside the
AsmPrinter. MCContext gets a pointer to this SourceMgr. Using one
SourceMgr per call to EmitInlineAsm would make it difficult for
MCContext to figure out in which SourceMgr the SMLoc is located,
while a single SourceMgr can figure it out if it has multiple
buffers.
The Str argument to EmitInlineAsm is copied into a buffer and owned
by the inline asm SourceMgr. This ensures that DiagHandlers won't
print garbage. (Clang emits a "note: instantiated into assembly
here", which refers to this string.)
The AsmParser gets destroyed before finalization, which means that
the DiagHandlers the AsmParser installs into the SourceMgr will be
stale. Restore the saved DiagHandlers.
Since now we're using just one SourceMgr for multiple inline asm
strings, we need to tell the AsmParser which buffer it needs to parse
currently. Hand a buffer id -- returned from SourceMgr::
AddNewSourceBuffer -- to the AsmParser.
Reviewers: rnk, grosbach, compnerd, rengolin, rovka, anemet
Reviewed By: rnk
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D29441
This improves error reporting for some inline assembly constructs that
clang does not approve of: instead of crashing with a "fatal backend
error", it will now show a normal error message, and point out the
location of the problematic assembly.
Reported by: mmel
MFC after: 1 week
3b78f6062f