[DWARF] Add CIE header fields address_size and segment_size when generating dwarf-4

[oota-llvm.git] / lib / MC / MCDwarf.cpp

diff --git a/lib/MC/MCDwarf.cpp b/lib/MC/MCDwarf.cpp
index e9f685eb88f6aaebf84a68094959bbd48e8fc04c..890b03170b027fd8f33cb54fa27c0b750cc4f2e6 100644 (file)
--- a/lib/MC/MCDwarf.cpp
+++ b/lib/MC/MCDwarf.cpp
@@ -1244,6 +1244,20 @@ void FrameEmitterImpl::EmitCompactUnwind(MCObjectStreamer &Streamer,
     Streamer.EmitIntValue(0, Size); // No LSDA
 }
 
+static unsigned getCIEVersion(bool IsEH, unsigned DwarfVersion) {
+  if (IsEH)
+    return 1;
+  switch (DwarfVersion) {
+  case 2:
+    return 1;
+  case 3:
+    return 3;
+  case 4:
+    return 4;
+  }
+  llvm_unreachable("Unknown version");
+}
+
 const MCSymbol &FrameEmitterImpl::EmitCIE(MCObjectStreamer &streamer,
                                           const MCSymbol *personality,
                                           unsigned personalityEncoding,
@@ -1270,9 +1284,7 @@ const MCSymbol &FrameEmitterImpl::EmitCIE(MCObjectStreamer &streamer,
   streamer.EmitIntValue(CIE_ID, 4);
 
   // Version
-  // For DWARF2, we use CIE version 1
-  // For DWARF3+, we use CIE version 3
-  uint8_t CIEVersion = context.getDwarfVersion() <= 2 ? 1 : 3;
+  uint8_t CIEVersion = getCIEVersion(IsEH, context.getDwarfVersion());
   streamer.EmitIntValue(CIEVersion, 1);
 
   // Augmentation String
@@ -1290,6 +1302,14 @@ const MCSymbol &FrameEmitterImpl::EmitCIE(MCObjectStreamer &streamer,
   }
   streamer.EmitIntValue(0, 1);
 
+  if (CIEVersion >= 4) {
+    // Address Size
+    streamer.EmitIntValue(context.getAsmInfo()->getPointerSize(), 1);
+
+    // Segment Descriptor Size
+    streamer.EmitIntValue(0, 1);
+  }
+
   // Code Alignment Factor
   streamer.EmitULEB128IntValue(context.getAsmInfo()->getMinInstAlignment());