4 files changed, 10 insertions, 7 deletions
diff --git a/llvm/lib/Target/X86/X86InstrInfo.cpp b/llvm/lib/Target/X86/X86InstrInfo.cpp
index 7b39fb311cb..8b9d0b80bab 100644
--- a/llvm/lib/Target/X86/X86InstrInfo.cpp
+++ b/llvm/lib/Target/X86/X86InstrInfo.cpp
@@ -2077,8 +2077,7 @@ void X86InstrInfo::storeRegToStackSlot(MachineBasicBlock &MBB,
                                        unsigned SrcReg, bool isKill, int FrameIdx,
                                        const TargetRegisterClass *RC) const {
   const MachineFunction &MF = *MBB.getParent();
-  bool isAligned = (RI.getStackAlignment() >= 16) ||
-    RI.needsStackRealignment(MF);
+  bool isAligned = (RI.getStackAlignment() >= 16) || RI.canRealignStack(MF);
   unsigned Opc = getStoreRegOpcode(SrcReg, RC, isAligned, TM);
   DebugLoc DL = DebugLoc::getUnknownLoc();
   if (MI != MBB.end()) DL = MI->getDebugLoc();
@@ -2172,8 +2171,7 @@ void X86InstrInfo::loadRegFromStackSlot(MachineBasicBlock &MBB,
                                         unsigned DestReg, int FrameIdx,
                                         const TargetRegisterClass *RC) const{
   const MachineFunction &MF = *MBB.getParent();
-  bool isAligned = (RI.getStackAlignment() >= 16) ||
-    RI.needsStackRealignment(MF);
+  bool isAligned = (RI.getStackAlignment() >= 16) || RI.canRealignStack(MF);
   unsigned Opc = getLoadRegOpcode(DestReg, RC, isAligned, TM);
   DebugLoc DL = DebugLoc::getUnknownLoc();
   if (MI != MBB.end()) DL = MI->getDebugLoc();
diff --git a/llvm/lib/Target/X86/X86RegisterInfo.cpp b/llvm/lib/Target/X86/X86RegisterInfo.cpp
index d96aafda603..4bc2c9e4b26 100644
--- a/llvm/lib/Target/X86/X86RegisterInfo.cpp
+++ b/llvm/lib/Target/X86/X86RegisterInfo.cpp
@@ -438,6 +438,12 @@ bool X86RegisterInfo::hasFP(const MachineFunction &MF) const {
           (MMI && MMI->callsUnwindInit()));
 }
 
+bool X86RegisterInfo::canRealignStack(const MachineFunction &MF) const {
+  const MachineFrameInfo *MFI = MF.getFrameInfo();
+  return (RealignStack &&
+          !MFI->hasVarSizedObjects());
+}
+
 bool X86RegisterInfo::needsStackRealignment(const MachineFunction &MF) const {
   const MachineFrameInfo *MFI = MF.getFrameInfo();
   bool requiresRealignment =
diff --git a/llvm/lib/Target/X86/X86RegisterInfo.h b/llvm/lib/Target/X86/X86RegisterInfo.h
index f281a3cf8e3..dec3fbaf974 100644
--- a/llvm/lib/Target/X86/X86RegisterInfo.h
+++ b/llvm/lib/Target/X86/X86RegisterInfo.h
@@ -128,6 +128,8 @@ public:
 
   bool hasFP(const MachineFunction &MF) const;
 
+  bool canRealignStack(const MachineFunction &MF) const;
+
   bool needsStackRealignment(const MachineFunction &MF) const;
 
   bool hasReservedCallFrame(MachineFunction &MF) const;
diff --git a/llvm/lib/Target/X86/X86TargetMachine.cpp b/llvm/lib/Target/X86/X86TargetMachine.cpp
index 445318e64fb..731c3ab5b24 100644
--- a/llvm/lib/Target/X86/X86TargetMachine.cpp
+++ b/llvm/lib/Target/X86/X86TargetMachine.cpp
@@ -157,9 +157,6 @@ bool X86TargetMachine::addInstSelector(PassManagerBase &PM,
 
 bool X86TargetMachine::addPreRegAlloc(PassManagerBase &PM,
                                       CodeGenOpt::Level OptLevel) {
-  // Calculate and set max stack object alignment early, so we can decide
-  // whether we will need stack realignment (and thus FP).
-  PM.add(createMaxStackAlignmentCalculatorPass());
   return false;  // -print-machineinstr shouldn't print after this.
 }