From 975f78ae79d56e8cb8285f00fdf829f3a094ee09 Mon Sep 17 00:00:00 2001
From: Dan Gohman <gohman@apple.com>
Date: Thu, 18 Dec 2008 22:01:52 +0000
Subject: [PATCH] When setting up the frame pointer, add it as a live-in
 register to all non-entry blocks, so that it doesn't appear use-before-def
 anywhere.

llvm-svn: 61214
---
 llvm/lib/Target/X86/X86RegisterInfo.cpp | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/llvm/lib/Target/X86/X86RegisterInfo.cpp b/llvm/lib/Target/X86/X86RegisterInfo.cpp
index 4bdfd8c101d9..4f4a33db74bb 100644
--- a/llvm/lib/Target/X86/X86RegisterInfo.cpp
+++ b/llvm/lib/Target/X86/X86RegisterInfo.cpp
@@ -745,6 +745,11 @@ void X86RegisterInfo::emitPrologue(MachineFunction &MF) const {
     BuildMI(MBB, MBBI, TII.get(Is64Bit ? X86::MOV64rr : X86::MOV32rr), FramePtr)
       .addReg(StackPtr);
 
+    // Mark the FramePtr as live-in in every block except the entry.
+    for (MachineFunction::iterator I = next(MF.begin()), E = MF.end();
+         I != E; ++I)
+      I->addLiveIn(FramePtr);
+
     // Realign stack
     if (needsStackRealignment(MF))
       BuildMI(MBB, MBBI,