From 1631ac16966f4f7210bc3b7d928a17e80541985a Mon Sep 17 00:00:00 2001
From: Reid Kleckner <rnk@google.com>
Date: Wed, 14 Feb 2018 00:24:29 +0000
Subject: [PATCH] [X86] Remove dead code from retpoline thunk generation

Follow-up to r325049

llvm-svn: 325085
---
 llvm/lib/Target/X86/X86RetpolineThunks.cpp | 26 ----------------------
 1 file changed, 26 deletions(-)

diff --git a/llvm/lib/Target/X86/X86RetpolineThunks.cpp b/llvm/lib/Target/X86/X86RetpolineThunks.cpp
index 59ace3f19fc6..d03826bbe992 100644
--- a/llvm/lib/Target/X86/X86RetpolineThunks.cpp
+++ b/llvm/lib/Target/X86/X86RetpolineThunks.cpp
@@ -74,7 +74,6 @@ private:
 
   void createThunkFunction(Module &M, StringRef Name);
   void insertRegReturnAddrClobber(MachineBasicBlock &MBB, unsigned Reg);
-  void insert32BitPushReturnAddrClobber(MachineBasicBlock &MBB);
   void populateThunk(MachineFunction &MF, Optional<unsigned> Reg = None);
 };
 
@@ -225,31 +224,6 @@ void X86RetpolineThunks::insertRegReturnAddrClobber(MachineBasicBlock &MBB,
       .addReg(Reg);
 }
 
-void X86RetpolineThunks::insert32BitPushReturnAddrClobber(
-    MachineBasicBlock &MBB) {
-  // The instruction sequence we use to replace the return address without
-  // a scratch register is somewhat complicated:
-  //   # Clear capture_spec from return address.
-  //   addl $4, %esp
-  //   # Top of stack words are: Callee, RA. Exchange Callee and RA.
-  //   pushl 4(%esp)  # Push callee
-  //   pushl 4(%esp)  # Push RA
-  //   popl 8(%esp)   # Pop RA to final RA
-  //   popl (%esp)    # Pop callee to next top of stack
-  //   retl           # Ret to callee
-  BuildMI(&MBB, DebugLoc(), TII->get(X86::ADD32ri), X86::ESP)
-      .addReg(X86::ESP)
-      .addImm(4);
-  addRegOffset(BuildMI(&MBB, DebugLoc(), TII->get(X86::PUSH32rmm)), X86::ESP,
-               false, 4);
-  addRegOffset(BuildMI(&MBB, DebugLoc(), TII->get(X86::PUSH32rmm)), X86::ESP,
-               false, 4);
-  addRegOffset(BuildMI(&MBB, DebugLoc(), TII->get(X86::POP32rmm)), X86::ESP,
-               false, 8);
-  addRegOffset(BuildMI(&MBB, DebugLoc(), TII->get(X86::POP32rmm)), X86::ESP,
-               false, 0);
-}
-
 void X86RetpolineThunks::populateThunk(MachineFunction &MF,
                                        Optional<unsigned> Reg) {
   // Set MF properties. We never use vregs...