Emit exception handling info for functions which are
not marked nounwind, or for all functions when -enable-eh
is set, provided the target supports Dwarf EH.

llvm-gcc generates nounwind in the right places; other FEs
will need to do so also.  Given such a FE, -enable-eh should
no longer be needed.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49006 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86AsmPrinter.cpp b/lib/Target/X86/X86AsmPrinter.cpp
index 98e7d9c..e1bc65f 100644
--- a/lib/Target/X86/X86AsmPrinter.cpp
+++ b/lib/Target/X86/X86AsmPrinter.cpp
@@ -381,9 +381,9 @@
 
     O << "\n";
 
-    if (ExceptionHandling && TAI->doesSupportExceptionHandling() && MMI &&
-        !Subtarget->is64Bit()) {
+    if (TAI->doesSupportExceptionHandling() && MMI && !Subtarget->is64Bit()) {
       // Add the (possibly multiple) personalities to the set of global values.
+      // Only referenced functions get into the Personalities list.
       const std::vector<Function *>& Personalities = MMI->getPersonalities();
 
       for (std::vector<Function *>::const_iterator I = Personalities.begin(),
diff --git a/lib/Target/X86/X86RegisterInfo.cpp b/lib/Target/X86/X86RegisterInfo.cpp
index 5cd2fbe..95026f2 100644
--- a/lib/Target/X86/X86RegisterInfo.cpp
+++ b/lib/Target/X86/X86RegisterInfo.cpp
@@ -504,6 +504,8 @@
   MachineModuleInfo *MMI = MFI->getMachineModuleInfo();
   X86MachineFunctionInfo *X86FI = MF.getInfo<X86MachineFunctionInfo>();
   MachineBasicBlock::iterator MBBI = MBB.begin();
+  bool needsFrameInfo = (MMI && MMI->hasDebugInfo()) ||
+      ExceptionHandling || !Fn->doesNotThrow();
   
   // Prepare for frame info.
   unsigned FrameLabelId = 0;
@@ -536,7 +538,7 @@
       .addReg(FramePtr);
     NumBytes -= SlotSize;
 
-    if (MMI && MMI->needsFrameInfo()) {
+    if (needsFrameInfo) {
       // Mark effective beginning of when frame pointer becomes valid.
       FrameLabelId = MMI->NextLabelID();
       BuildMI(MBB, MBBI, TII.get(X86::LABEL)).addImm(FrameLabelId).addImm(0);
@@ -548,7 +550,7 @@
   }
   
   unsigned ReadyLabelId = 0;
-  if (MMI && MMI->needsFrameInfo()) {
+  if (needsFrameInfo) {
     // Mark effective beginning of when frame pointer is ready.
     ReadyLabelId = MMI->NextLabelID();
     BuildMI(MBB, MBBI, TII.get(X86::LABEL)).addImm(ReadyLabelId).addImm(0);
@@ -607,7 +609,7 @@
     }
   }
 
-  if (MMI && MMI->needsFrameInfo()) {
+  if (needsFrameInfo) {
     std::vector<MachineMove> &Moves = MMI->getFrameMoves();
     const TargetData *TD = MF.getTarget().getTargetData();