[WinEH] Allow CatchHigh to be equal to TryHigh

[oota-llvm.git] / lib / CodeGen / AsmPrinter / Win64Exception.cpp

diff --git a/lib/CodeGen/AsmPrinter/Win64Exception.cpp b/lib/CodeGen/AsmPrinter/Win64Exception.cpp
index 3bfcaa96593dac666f3b440dcec01380c680c2e7..c5f1df883559df493bca8f9a71fa29b5cc375698 100644 (file)
--- a/lib/CodeGen/AsmPrinter/Win64Exception.cpp
+++ b/lib/CodeGen/AsmPrinter/Win64Exception.cpp
@@ -108,8 +108,13 @@ void Win64Exception::endFunction(const MachineFunction *MF) {
   if (!shouldEmitPersonality && !shouldEmitMoves)
     return;
 
-  // Map all labels and get rid of any dead landing pads.
-  MMI->TidyLandingPads();
+  EHPersonality Per = MMI->getPersonalityType();
+
+  // Get rid of any dead landing pads if we're not using a Windows EH scheme. In
+  // Windows EH schemes, the landing pad is not actually reachable. It only
+  // exists so that we can emit the right table data.
+  if (!isMSVCEHPersonality(Per))
+    MMI->TidyLandingPads();
 
   if (shouldEmitPersonality) {
     Asm->OutStreamer.PushSection();
@@ -119,7 +124,6 @@ void Win64Exception::endFunction(const MachineFunction *MF) {
 
     // Emit the tables appropriate to the personality function in use. If we
     // don't recognize the personality, assume it uses an Itanium-style LSDA.
-    EHPersonality Per = MMI->getPersonalityType();
     if (Per == EHPersonality::MSVC_Win64SEH)
       emitCSpecificHandlerTable();
     else if (Per == EHPersonality::MSVC_CXX)
@@ -343,7 +347,13 @@ void Win64Exception::emitCXXFrameHandler3Table(const MachineFunction *MF) {
     }
   }
 
-  if (ParentF != F)
+  // Defer emission until we've visited the parent function and all the catch
+  // handlers.  Cleanups don't contribute to the ip2state table yet, so don't
+  // count them.
+  if (ParentF != F && !FuncInfo.CatchHandlerMaxState.count(F))
+    return;
+  ++FuncInfo.NumIPToStateFuncsVisited;
+  if (FuncInfo.NumIPToStateFuncsVisited != FuncInfo.CatchHandlerMaxState.size())
     return;
 
   MCSymbol *UnwindMapXData = nullptr;
@@ -427,7 +437,7 @@ void Win64Exception::emitCXXFrameHandler3Table(const MachineFunction *MF) {
             std::max(CatchHigh, FuncInfo.CatchHandlerMaxState[HT.Handler]);
 
       assert(TBME.TryLow <= TBME.TryHigh);
-      assert(CatchHigh > TBME.TryHigh);
+      assert(CatchHigh >= TBME.TryHigh);
       OS.EmitIntValue(TBME.TryLow, 4);                    // TryLow
       OS.EmitIntValue(TBME.TryHigh, 4);                   // TryHigh
       OS.EmitIntValue(CatchHigh, 4);                      // CatchHigh
@@ -455,12 +465,20 @@ void Win64Exception::emitCXXFrameHandler3Table(const MachineFunction *MF) {
         const MCSymbolRefExpr *ParentFrameOffsetRef = MCSymbolRefExpr::Create(
             ParentFrameOffset, MCSymbolRefExpr::VK_None, Asm->OutContext);
 
-        MCSymbol *FrameAllocOffset =
-            Asm->OutContext.getOrCreateFrameAllocSymbol(
-                GlobalValue::getRealLinkageName(F->getName()),
-                HT.CatchObjRecoverIdx);
-        const MCSymbolRefExpr *FrameAllocOffsetRef = MCSymbolRefExpr::Create(
-            FrameAllocOffset, MCSymbolRefExpr::VK_None, Asm->OutContext);
+        // Get the frame escape label with the offset of the catch object. If
+        // the index is -1, then there is no catch object, and we should emit an
+        // offset of zero, indicating that no copy will occur.
+        const MCExpr *FrameAllocOffsetRef = nullptr;
+        if (HT.CatchObjRecoverIdx >= 0) {
+          MCSymbol *FrameAllocOffset =
+              Asm->OutContext.getOrCreateFrameAllocSymbol(
+                  GlobalValue::getRealLinkageName(ParentF->getName()),
+                  HT.CatchObjRecoverIdx);
+          FrameAllocOffsetRef = MCSymbolRefExpr::Create(
+              FrameAllocOffset, MCSymbolRefExpr::VK_None, Asm->OutContext);
+        } else {
+          FrameAllocOffsetRef = MCConstantExpr::Create(0, Asm->OutContext);
+        }
 
         OS.EmitIntValue(HT.Adjectives, 4);                    // Adjectives
         OS.EmitValue(createImageRel32(HT.TypeDescriptor), 4); // Type