From ec37b00b17fba355ac6d4a1bee918d3004c54584 Mon Sep 17 00:00:00 2001
From: Cameron Esfahani <dirty@apple.com>
Date: Fri, 8 Oct 2010 19:24:18 +0000
Subject: [PATCH] Recommit 116056, now with the missing file...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116083 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/X86/X86ISelLowering.cpp  |  6 +++++-
 lib/Target/X86/X86TargetMachine.cpp |  3 ++-
 test/CodeGen/X86/win64_params.ll    | 11 +++++++++++
 3 files changed, 18 insertions(+), 2 deletions(-)
 create mode 100644 test/CodeGen/X86/win64_params.ll

diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index 66f9612e027..27226d885d7 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -1701,8 +1701,12 @@ X86TargetLowering::LowerFormalArguments(SDValue Chain,
         TotalNumXMMRegs = 0;
 
       if (IsWin64) {
+        const TargetFrameInfo &TFI = *getTargetMachine().getFrameInfo();
+        // Get to the caller-allocated home save location.  Add 8 to account
+        // for the return address.
+        int HomeOffset = TFI.getOffsetOfLocalArea() + 8;
         FuncInfo->setRegSaveFrameIndex(
-          MFI->CreateFixedObject(1, NumIntRegs * 8, false));
+          MFI->CreateFixedObject(1, NumIntRegs * 8 + HomeOffset, false));
         FuncInfo->setVarArgsFrameIndex(FuncInfo->getRegSaveFrameIndex());
       } else {
         // For X86-64, if there are vararg parameters that are passed via
diff --git a/lib/Target/X86/X86TargetMachine.cpp b/lib/Target/X86/X86TargetMachine.cpp
index ad2980e558b..4e435eecb1e 100644
--- a/lib/Target/X86/X86TargetMachine.cpp
+++ b/lib/Target/X86/X86TargetMachine.cpp
@@ -121,7 +121,8 @@ X86TargetMachine::X86TargetMachine(const Target &T, const std::string &TT,
     Subtarget(TT, FS, is64Bit),
     FrameInfo(TargetFrameInfo::StackGrowsDown,
               Subtarget.getStackAlignment(),
-              Subtarget.is64Bit() ? -8 : -4),
+              (Subtarget.isTargetWin64() ? -40 :
+               (Subtarget.is64Bit() ? -8 : -4))),
     ELFWriterInfo(is64Bit, true) {
   DefRelocModel = getRelocationModel();
 
diff --git a/test/CodeGen/X86/win64_params.ll b/test/CodeGen/X86/win64_params.ll
new file mode 100644
index 00000000000..0b67368e04f
--- /dev/null
+++ b/test/CodeGen/X86/win64_params.ll
@@ -0,0 +1,11 @@
+; RUN: llc < %s -mtriple=x86_64-pc-win32 | FileCheck %s
+
+; Verify that the 5th and 6th parameters are coming from the correct location
+; on the stack.
+define i32 @f6(i32 %p1, i32 %p2, i32 %p3, i32 %p4, i32 %p5, i32 %p6) nounwind readnone optsize {
+entry:
+; CHECK: movl    80(%rsp), %eax
+; CHECK: addl    72(%rsp), %eax
+  %add = add nsw i32 %p6, %p5
+  ret i32 %add
+}
-- 
2.34.1