From 1a8d918ef19b71181dcbd6b2dbb84969de8fe75c Mon Sep 17 00:00:00 2001
From: Chris Lattner <sabre@nondot.org>
Date: Fri, 13 Jan 2006 18:00:54 +0000
Subject: [PATCH] Enable X86 support for savestack/restorestack

llvm-svn: 25278
---
 llvm/lib/Target/X86/X86ISelLowering.cpp | 1 +
 llvm/lib/Target/X86/X86ISelPattern.cpp  | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
index 6a2fb684a850..776780ff531c 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -39,6 +39,7 @@ X86TargetLowering::X86TargetLowering(TargetMachine &TM)
   setSetCCResultType(MVT::i8);
   setSetCCResultContents(ZeroOrOneSetCCResult);
   setShiftAmountFlavor(Mask);   // shl X, 32 == shl X, 0
+  setStackPointerRegisterToSaveRestore(X86::ESP);
 
   // Set up the register classes.
   addRegisterClass(MVT::i8, X86::R8RegisterClass);
diff --git a/llvm/lib/Target/X86/X86ISelPattern.cpp b/llvm/lib/Target/X86/X86ISelPattern.cpp
index cb1835489c1a..c5d5a26666f7 100644
--- a/llvm/lib/Target/X86/X86ISelPattern.cpp
+++ b/llvm/lib/Target/X86/X86ISelPattern.cpp
@@ -1229,7 +1229,7 @@ unsigned ISel::SelectExpr(SDOperand N) {
       cast<RegisterSDNode>(Node->getOperand(1))->getReg() :
       cast<RegisterSDNode>(Node)->getReg();
     // Just use the specified register as our input if we can.
-    if (MRegisterInfo::isVirtualRegister(Reg) || Reg == X86::ESP)
+    if (MRegisterInfo::isVirtualRegister(Reg))
       return Reg;
   }