From ec0445855179d2c9fb98a2c8a42e03525762f45f Mon Sep 17 00:00:00 2001
From: Bill Wendling <isanbard@gmail.com>
Date: Wed, 18 Nov 2009 23:18:46 +0000
Subject: [PATCH] Attempt #2:

Place the EH table in the __TEXT section on MachO. It saves space.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89270 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/CodeGen/AsmPrinter/DwarfException.cpp | 34 +++++++++++++++++++----
 lib/Target/TargetLoweringObjectFile.cpp   |  2 +-
 2 files changed, 29 insertions(+), 7 deletions(-)

diff --git a/lib/CodeGen/AsmPrinter/DwarfException.cpp b/lib/CodeGen/AsmPrinter/DwarfException.cpp
index 1c8b8f46472..4f6e685a37a 100644
--- a/lib/CodeGen/AsmPrinter/DwarfException.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfException.cpp
@@ -727,7 +727,8 @@ void DwarfException::EmitExceptionTable() {
     // somewhere.  This predicate should be moved to a shared location that is
     // in target-independent code.
     //
-    if (LSDASection->getKind().isWriteable() ||
+    if ((LSDASection->getKind().isWriteable() &&
+         !LSDASection->getKind().isDataRel()) ||
         Asm->TM.getRelocationModel() == Reloc::Static)
       TTypeFormat = dwarf::DW_EH_PE_absptr;
     else
@@ -917,14 +918,35 @@ void DwarfException::EmitExceptionTable() {
   }
 
   // Emit the Catch TypeInfos.
+  const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
+  unsigned Index = 1;
+
   for (std::vector<GlobalVariable *>::const_reverse_iterator
-         I = TypeInfos.rbegin(), E = TypeInfos.rend(); I != E; ++I) {
-    const GlobalVariable *GV = *I;
-    PrintRelDirective();
+         I = TypeInfos.rbegin(), E = TypeInfos.rend(); I != E; ++I, ++Index) {
+    const GlobalVariable *TI = *I;
+
+    if (TI) {
+      if (!LSDASection->getKind().isDataRel() &&
+          (TTypeFormat == dwarf::DW_EH_PE_absptr ||
+           TI->getLinkage() == GlobalValue::InternalLinkage)) {
+        // Print out the unadorned name of the type info.
+        PrintRelDirective();
+        O << Asm->Mang->getMangledName(TI);
+      } else {
+        bool IsTypeInfoIndirect = false, IsTypeInfoPCRel = false;
+        const MCExpr *TypeInfoRef =
+          TLOF.getSymbolForDwarfGlobalReference(TI, Asm->Mang, Asm->MMI,
+                                                IsTypeInfoIndirect,
+                                                IsTypeInfoPCRel);
 
-    if (GV) {
-      O << Asm->Mang->getMangledName(GV);
+        if (!IsTypeInfoPCRel)
+          TypeInfoRef = CreateLabelDiff(TypeInfoRef, "typeinforef_addr", Index);
+
+        O << MAI->getData32bitsDirective();
+        TypeInfoRef->print(O, MAI);
+      }
     } else {
+      PrintRelDirective();
       O << "0x0";
     }
 
diff --git a/lib/Target/TargetLoweringObjectFile.cpp b/lib/Target/TargetLoweringObjectFile.cpp
index f887523c5b7..e36e453a83d 100644
--- a/lib/Target/TargetLoweringObjectFile.cpp
+++ b/lib/Target/TargetLoweringObjectFile.cpp
@@ -783,7 +783,7 @@ void TargetLoweringObjectFileMachO::Initialize(MCContext &Ctx,
   }
 
   // Exception Handling.
-  LSDASection = getMachOSection("__DATA", "__gcc_except_tab", 0,
+  LSDASection = getMachOSection("__TEXT", "__gcc_except_tab", 0,
                                 SectionKind::getDataRel());
   EHFrameSection =
     getMachOSection("__TEXT", "__eh_frame",
-- 
2.34.1