From b9cffadc06cac0f91e2681484c9d8fa618a7e1d3 Mon Sep 17 00:00:00 2001
From: "Michael J. Spencer" <bigcheesegs@gmail.com>
Date: Thu, 21 Oct 2010 00:08:21 +0000
Subject: [PATCH] CodeGen-Windows: Only emit _fltused if a VarArg function is
 called with floating point args. This should be the minimum set of functions
 that could possibly need it.

llvm-svn: 116978
---
 include/llvm/CodeGen/MachineModuleInfo.h         | 15 +++++++--------
 lib/CodeGen/MachineModuleInfo.cpp                |  2 +-
 lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp | 10 +++++-----
 lib/Target/X86/X86AsmPrinter.cpp                 |  2 +-
 4 files changed, 14 insertions(+), 15 deletions(-)

diff --git a/include/llvm/CodeGen/MachineModuleInfo.h b/include/llvm/CodeGen/MachineModuleInfo.h
index 4376478ec2e..43405c09376 100644
--- a/include/llvm/CodeGen/MachineModuleInfo.h
+++ b/include/llvm/CodeGen/MachineModuleInfo.h
@@ -157,10 +157,9 @@ class MachineModuleInfo : public ImmutablePass {
   /// in this module.
   bool DbgInfoAvailable;
 
-  /// True if this module calls an external function with floating point
-  /// arguments. This is used to emit an undefined reference to fltused on
-  /// Windows targets.
-  bool CallsExternalFunctionWithFloatingPointArguments;
+  /// True if this module calls VarArg function with floating point arguments.
+  /// This is used to emit an undefined reference to fltused on Windows targets.
+  bool CallsExternalVAFunctionWithFloatingPointArguments;
 
 public:
   static char ID; // Pass identification, replacement for typeid
@@ -217,12 +216,12 @@ public:
   bool callsUnwindInit() const { return CallsUnwindInit; }
   void setCallsUnwindInit(bool b) { CallsUnwindInit = b; }
 
-  bool callsExternalFunctionWithFloatingPointArguments() const {
-    return CallsExternalFunctionWithFloatingPointArguments;
+  bool callsExternalVAFunctionWithFloatingPointArguments() const {
+    return CallsExternalVAFunctionWithFloatingPointArguments;
   }
 
-  void setCallsExternalFunctionWithFloatingPointArguments(bool b) {
-    CallsExternalFunctionWithFloatingPointArguments = b;
+  void setCallsExternalVAFunctionWithFloatingPointArguments(bool b) {
+    CallsExternalVAFunctionWithFloatingPointArguments = b;
   }
 
   /// getFrameMoves - Returns a reference to a list of moves done in the current
diff --git a/lib/CodeGen/MachineModuleInfo.cpp b/lib/CodeGen/MachineModuleInfo.cpp
index 5c8b37315cd..79622e8df3e 100644
--- a/lib/CodeGen/MachineModuleInfo.cpp
+++ b/lib/CodeGen/MachineModuleInfo.cpp
@@ -257,7 +257,7 @@ MachineModuleInfo::MachineModuleInfo(const MCAsmInfo &MAI)
 : ImmutablePass(ID), Context(MAI),
   ObjFileMMI(0),
   CurCallSite(0), CallsEHReturn(0), CallsUnwindInit(0), DbgInfoAvailable(false),
-  CallsExternalFunctionWithFloatingPointArguments(false) {
+  CallsExternalVAFunctionWithFloatingPointArguments(false) {
   initializeMachineModuleInfoPass(*PassRegistry::getPassRegistry());
   // Always emit some info, by default "no personality" info.
   Personalities.push_back(NULL);
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index a68b7b0f947..4be2525cfa1 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -5030,16 +5030,16 @@ void SelectionDAGBuilder::visitCall(const CallInst &I) {
     // See if any floating point values are being passed to this external
     // function. This is used to emit an undefined reference to fltused on
     // Windows.
-    if (!F->hasLocalLinkage() && F->hasName()) {
-      MachineModuleInfo &MMI = DAG.getMachineFunction().getMMI();
-      for (unsigned i = 0, e = I.getNumArgOperands(); i != e &&
-                  !MMI.callsExternalFunctionWithFloatingPointArguments(); ++i) {
+    MachineModuleInfo &MMI = DAG.getMachineFunction().getMMI();
+    if (F->isVarArg() &&
+        !MMI.callsExternalVAFunctionWithFloatingPointArguments()) {
+      for (unsigned i = 0, e = I.getNumArgOperands(); i != e; ++i) {
         const Type* T = I.getArgOperand(i)->getType();
         for (po_iterator<const Type*> i = po_begin(T),
                                       e = po_end(T);
                                       i != e; ++i) {
           if (i->isFloatingPointTy()) {
-            MMI.setCallsExternalFunctionWithFloatingPointArguments(true);
+            MMI.setCallsExternalVAFunctionWithFloatingPointArguments(true);
             break;
           }
         }
diff --git a/lib/Target/X86/X86AsmPrinter.cpp b/lib/Target/X86/X86AsmPrinter.cpp
index c4fd7298b57..f7cb9e71f67 100644
--- a/lib/Target/X86/X86AsmPrinter.cpp
+++ b/lib/Target/X86/X86AsmPrinter.cpp
@@ -582,7 +582,7 @@ void X86AsmPrinter::EmitEndOfAsmFile(Module &M) {
 
   if (Subtarget->isTargetWindows()
    && !Subtarget->isTargetCygMing()
-   && MMI->callsExternalFunctionWithFloatingPointArguments()) {
+   && MMI->callsExternalVAFunctionWithFloatingPointArguments()) {
     MCSymbol *S = MMI->getContext().GetOrCreateSymbol(StringRef("__fltused"));
     OutStreamer.EmitSymbolAttribute(S, MCSA_Global);
   }