TargetLowering: Add finalizeLowering() function; NFC

Adds a new method finalizeLowering to TargetLoweringBase. This is in
preparation for an upcoming commit.

This function is meant for target specific adjustments to
MachineFrameInfo or register reservations.

Move the freezeRegisters() and the hasCopyImplyingStackAdjustment()
handling into the new function to prove the concept. As an added bonus
GlobalISel no longer missed the hasCopyImplyingStackAdjustment()
handling with this.

Differential Revision: https://reviews.llvm.org/D32621

llvm-svn: 301679

2 files changed, 14 insertions, 8 deletions

diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
index 7491e45ec70..535be01abc5 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -35169,14 +35169,21 @@ bool X86TargetLowering::isTypeDesirableForOp(unsigned Opc, EVT VT) const {
 /// know that the code that lowers COPY of EFLAGS has to use the stack, and if
 /// we don't adjust the stack we clobber the first frame index.
 /// See X86InstrInfo::copyPhysReg.
-bool X86TargetLowering::hasCopyImplyingStackAdjustment(
-    MachineFunction *MF) const {
-  const MachineRegisterInfo &MRI = MF->getRegInfo();
-
+static bool hasCopyImplyingStackAdjustment(const MachineFunction &MF) {
+  const MachineRegisterInfo &MRI = MF.getRegInfo();
   return any_of(MRI.reg_instructions(X86::EFLAGS),
                 [](const MachineInstr &RI) { return RI.isCopy(); });
 }
 
+void X86TargetLowering::finalizeLowering(MachineFunction &MF) const {
+  if (hasCopyImplyingStackAdjustment(MF)) {
+    MachineFrameInfo &MFI = MF.getFrameInfo();
+    MFI.setHasCopyImplyingStackAdjustment(true);
+  }
+
+  TargetLoweringBase::finalizeLowering(MF);
+}
+
 /// This method query the target whether it is beneficial for dag combiner to
 /// promote the specified node. If true, it should return the desired promotion
 /// type by reference.
diff --git a/llvm/lib/Target/X86/X86ISelLowering.h b/llvm/lib/Target/X86/X86ISelLowering.h
index ec6bb904f6f..46dc587c637 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.h
+++ b/llvm/lib/Target/X86/X86ISelLowering.h
@@ -773,10 +773,6 @@ namespace llvm {
     /// and some i16 instructions are slow.
     bool IsDesirableToPromoteOp(SDValue Op, EVT &PVT) const override;
 
-    /// Return true if the MachineFunction contains a COPY which would imply
-    /// HasOpaqueSPAdjustment.
-    bool hasCopyImplyingStackAdjustment(MachineFunction *MF) const override;
-
     MachineBasicBlock *
     EmitInstrWithCustomInserter(MachineInstr &MI,
                                 MachineBasicBlock *MBB) const override;
@@ -1065,6 +1061,9 @@ namespace llvm {
                               ArrayRef<ShuffleVectorInst *> Shuffles,
                               ArrayRef<unsigned> Indices,
                               unsigned Factor) const override;
+
+    void finalizeLowering(MachineFunction &MF) const override;
+
   protected:
     std::pair<const TargetRegisterClass *, uint8_t>
     findRepresentativeClass(const TargetRegisterInfo *TRI,