[MC] Add support for encoding CodeView variable definition ranges

CodeView, like most other debug formats, represents the live range of a
variable so that debuggers might print them out.

They use a variety of records to represent how a particular variable
might be available (in a register, in a frame pointer, etc.) along with
a set of ranges where this debug information is relevant.

However, the format only allows us to use ranges which are limited to a
maximum of 0xF000 in size.  This means that we need to split our debug
information into chunks of 0xF000.

Because the layout of code is not known until *very* late, we must use a
new fragment to record the information we need until we can know
*exactly* what the range is.

llvm-svn: 259868

1 files changed, 4 insertions, 0 deletions

diff --git a/llvm/lib/MC/MCStreamer.cpp b/llvm/lib/MC/MCStreamer.cpp
index 8ee41261..663ed83 100644
--- a/llvm/lib/MC/MCStreamer.cpp
+++ b/llvm/lib/MC/MCStreamer.cpp
@@ -201,6 +201,10 @@ void MCStreamer::EmitCVInlineLinetableDirective(
     const MCSymbol *FnStartSym, const MCSymbol *FnEndSym,
     ArrayRef<unsigned> SecondaryFunctionIds) {}
 
+void MCStreamer::EmitCVDefRangeDirective(
+    ArrayRef<std::pair<const MCSymbol *, const MCSymbol *>> Ranges,
+    StringRef FixedSizePortion) {}
+
 void MCStreamer::EmitEHSymAttributes(const MCSymbol *Symbol,
                                      MCSymbol *EHSymbol) {
 }