[X86] Determine if we have an OpaqueSPAdjustment earlier

We queried hasFP before we hit ExpandISelPseudos.  ExpandISelPseudos
manipulated state that hasFP relied on, potentially changing the result
after it has been queried elsewhere.

While I am not aware of any particular bug due to this state of affairs,
it seems best to avoid it entirely by changing the state during DAG
construction.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256849 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index 6d748ca51645c1f517120266bf9a549d71bc1bfc..b9863d1dea2bd63dc4c3065da019b6766722c356 100644 (file)
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -17374,6 +17374,18 @@ static SDValue LowerINTRINSIC_W_CHAIN(SDValue Op, const X86Subtarget *Subtarget,
   if (!IntrData) {
     if (IntNo == llvm::Intrinsic::x86_seh_ehregnode)
       return MarkEHRegistrationNode(Op, DAG);
+    if (IntNo == llvm::Intrinsic::x86_flags_read_u32 ||
+        IntNo == llvm::Intrinsic::x86_flags_read_u64 ||
+        IntNo == llvm::Intrinsic::x86_flags_write_u32 ||
+        IntNo == llvm::Intrinsic::x86_flags_write_u64) {
+      // We need a frame pointer because this will get lowered to a PUSH/POP
+      // sequence.
+      MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo();
+      MFI->setHasOpaqueSPAdjustment(true);
+      // Don't do anything here, we will expand these intrinsics out later
+      // during ExpandISelPseudos in EmitInstrWithCustomInserter.
+      return SDValue();
+    }
     return SDValue();
   }
 
@@ -22541,8 +22553,6 @@ X86TargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
   case X86::RDFLAGS32:
   case X86::RDFLAGS64: {
     DebugLoc DL = MI->getDebugLoc();
-    MachineFunction *MF = BB->getParent();
-    MF->getFrameInfo()->setHasOpaqueSPAdjustment(true);
     const TargetInstrInfo *TII = Subtarget->getInstrInfo();
     unsigned PushF =
         MI->getOpcode() == X86::RDFLAGS32 ? X86::PUSHF32 : X86::PUSHF64;
@@ -22558,8 +22568,6 @@ X86TargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
   case X86::WRFLAGS32:
   case X86::WRFLAGS64: {
     DebugLoc DL = MI->getDebugLoc();
-    MachineFunction *MF = BB->getParent();
-    MF->getFrameInfo()->setHasOpaqueSPAdjustment(true);
     const TargetInstrInfo *TII = Subtarget->getInstrInfo();
     unsigned Push =
         MI->getOpcode() == X86::WRFLAGS32 ? X86::PUSH32r : X86::PUSH64r;