[WinEH] Move WinEHFuncInfo from MachineModuleInfo to MachineFunction

Summary:
Now that there is a one-to-one mapping from MachineFunction to
WinEHFuncInfo, we don't need to use a DenseMap to select the right
WinEHFuncInfo for the current funclet.

The main challenge here is that X86WinEHStatePass is an IR pass that
doesn't have access to the MachineFunction. I gave it its own
WinEHFuncInfo object that it uses to calculate state numbers, which it
then throws away. As long as nobody creates or removes EH pads between
this pass and SDAG construction, we will get the same state numbers.

The other thing X86WinEHStatePass does is to mark the EH registration
node. Instead of communicating which alloca was the registration through
WinEHFuncInfo, I added the llvm.x86.seh.ehregnode intrinsic.  This
intrinsic generates no code and simply marks the alloca in use.

Reviewers: JCTremoulet

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D14668

llvm-svn: 253378

1 files changed, 5 insertions, 8 deletions

diff --git a/llvm/lib/Target/X86/X86FrameLowering.cpp b/llvm/lib/Target/X86/X86FrameLowering.cpp
index 72baa078661..4fbe3613d1e 100644
--- a/llvm/lib/Target/X86/X86FrameLowering.cpp
+++ b/llvm/lib/Target/X86/X86FrameLowering.cpp
@@ -1252,7 +1252,7 @@ void X86FrameLowering::emitPrologue(MachineFunction &MF,
       assert(classifyEHPersonality(Fn->getPersonalityFn()) ==
              EHPersonality::MSVC_CXX);
       unsigned FrameReg;
-      int FI = MMI.getWinEHFuncInfo(Fn).EHRegNodeFrameIndex;
+      int FI = MF.getWinEHFuncInfo()->EHRegNodeFrameIndex;
       int64_t EHRegOffset = getFrameIndexReference(MF, FI, FrameReg);
       // ESP is the first field, so no extra displacement is needed.
       addRegOffset(BuildMI(MBB, MBBI, DL, TII.get(X86::MOV32mr)), FrameReg,
@@ -1292,7 +1292,7 @@ void X86FrameLowering::emitPrologue(MachineFunction &MF,
     // and the GC can recover it.
     unsigned PSPSlotOffset = getPSPSlotOffsetFromSP(MF);
     auto PSPInfo = MachinePointerInfo::getFixedStack(
-        MF, MF.getMMI().getWinEHFuncInfo(Fn).PSPSymFrameIdx);
+        MF, MF.getWinEHFuncInfo()->PSPSymFrameIdx);
     addRegOffset(BuildMI(MBB, MBBI, DL, TII.get(X86::MOV64mr)), StackPtr, false,
                  PSPSlotOffset)
         .addReg(StackPtr)
@@ -1401,8 +1401,7 @@ static bool isFuncletReturnInstr(MachineInstr *MI) {
 // frame with only a single offset reported for the entire method.
 unsigned
 X86FrameLowering::getPSPSlotOffsetFromSP(const MachineFunction &MF) const {
-  MachineModuleInfo &MMI = MF.getMMI();
-  WinEHFuncInfo &Info = MMI.getWinEHFuncInfo(MF.getFunction());
+  const WinEHFuncInfo &Info = *MF.getWinEHFuncInfo();
   // getFrameIndexReferenceFromSP has an out ref parameter for the stack
   // pointer register; pass a dummy that we ignore
   unsigned SPReg;
@@ -2592,9 +2591,7 @@ MachineBasicBlock::iterator X86FrameLowering::restoreWin32EHStackPointers(
   MachineFunction &MF = *MBB.getParent();
   unsigned FramePtr = TRI->getFrameRegister(MF);
   unsigned BasePtr = TRI->getBaseRegister();
-  MachineModuleInfo &MMI = MF.getMMI();
-  const Function *Fn = MF.getFunction();
-  WinEHFuncInfo &FuncInfo = MMI.getWinEHFuncInfo(Fn);
+  WinEHFuncInfo &FuncInfo = *MF.getWinEHFuncInfo();
   X86MachineFunctionInfo *X86FI = MF.getInfo<X86MachineFunctionInfo>();
   MachineFrameInfo *MFI = MF.getFrameInfo();
 
@@ -2679,7 +2676,7 @@ void X86FrameLowering::processFunctionBeforeFrameFinalized(
   int64_t UnwindHelpOffset = MinFixedObjOffset - SlotSize;
   int UnwindHelpFI =
       MFI->CreateFixedObject(SlotSize, UnwindHelpOffset, /*Immutable=*/false);
-  MF.getMMI().getWinEHFuncInfo(Fn).UnwindHelpFrameIdx = UnwindHelpFI;
+  MF.getWinEHFuncInfo()->UnwindHelpFrameIdx = UnwindHelpFI;
 
   // Store -2 into UnwindHelp on function entry. We have to scan forwards past
   // other frame setup instructions.