From d4b74591791834e8d0d27a83127d63cb772522b7 Mon Sep 17 00:00:00 2001
From: Evan Cheng <evan.cheng@apple.com>
Date: Thu, 4 Dec 2008 01:56:50 +0000
Subject: [PATCH] Visibility hidden GVs do not require extra load of symbol
 address from the GOT or non-lazy-ptr.

llvm-svn: 60519
---
 lib/Target/ARM/ARMISelLowering.cpp              |  2 +-
 lib/Target/PowerPC/AsmPrinter/PPCAsmPrinter.cpp |  5 +++--
 lib/Target/PowerPC/PPCSubtarget.cpp             |  4 +++-
 lib/Target/X86/AsmPrinter/X86ATTAsmPrinter.cpp  |  2 ++
 lib/Target/X86/X86Subtarget.cpp                 |  3 +++
 test/CodeGen/X86/hidden-vis-2.ll                | 10 ++++++++++
 6 files changed, 22 insertions(+), 4 deletions(-)
 create mode 100644 test/CodeGen/X86/hidden-vis-2.ll

diff --git a/lib/Target/ARM/ARMISelLowering.cpp b/lib/Target/ARM/ARMISelLowering.cpp
index 69452c13601..42aee2677cd 100644
--- a/lib/Target/ARM/ARMISelLowering.cpp
+++ b/lib/Target/ARM/ARMISelLowering.cpp
@@ -830,7 +830,7 @@ SDValue ARMTargetLowering::LowerGlobalAddressELF(SDValue Op,
 /// GVIsIndirectSymbol - true if the GV will be accessed via an indirect symbol
 /// even in non-static mode.
 static bool GVIsIndirectSymbol(GlobalValue *GV, Reloc::Model RelocM) {
-  return RelocM != Reloc::Static &&
+  return RelocM != Reloc::Static && !GV->hasHiddenVisibility() &&
     (GV->hasWeakLinkage() || GV->hasLinkOnceLinkage() ||
      (GV->isDeclaration() && !GV->hasNotBeenReadFromBitcode()));
 }
diff --git a/lib/Target/PowerPC/AsmPrinter/PPCAsmPrinter.cpp b/lib/Target/PowerPC/AsmPrinter/PPCAsmPrinter.cpp
index 3ed72658401..8d91b5c2f1e 100644
--- a/lib/Target/PowerPC/AsmPrinter/PPCAsmPrinter.cpp
+++ b/lib/Target/PowerPC/AsmPrinter/PPCAsmPrinter.cpp
@@ -387,8 +387,9 @@ void PPCAsmPrinter::printOp(const MachineOperand &MO) {
 
     // External or weakly linked global variables need non-lazily-resolved stubs
     if (TM.getRelocationModel() != Reloc::Static) {
-      if (((GV->isDeclaration() || GV->hasWeakLinkage() ||
-            GV->hasLinkOnceLinkage() || GV->hasCommonLinkage()))) {
+      if (!GV->hasHiddenVisibility() &&
+          (GV->isDeclaration() || GV->hasWeakLinkage() ||
+           GV->hasLinkOnceLinkage() || GV->hasCommonLinkage())) {
         GVStubs.insert(Name);
         printSuffixedName(Name, "$non_lazy_ptr");
         if (GV->hasExternalWeakLinkage())
diff --git a/lib/Target/PowerPC/PPCSubtarget.cpp b/lib/Target/PowerPC/PPCSubtarget.cpp
index 14983fcf1de..aef47866bf2 100644
--- a/lib/Target/PowerPC/PPCSubtarget.cpp
+++ b/lib/Target/PowerPC/PPCSubtarget.cpp
@@ -141,7 +141,9 @@ bool PPCSubtarget::hasLazyResolverStub(const GlobalValue *GV) const {
   // We never hae stubs if HasLazyResolverStubs=false or if in static mode.
   if (!HasLazyResolverStubs || TM.getRelocationModel() == Reloc::Static)
     return false;
-  
+  // Extra load is not needed for symbols with hidden visibility.
+  if (GV->hasHiddenVisibility())
+    return false;
   return GV->hasWeakLinkage() || GV->hasLinkOnceLinkage() ||
          GV->hasCommonLinkage() ||
          (GV->isDeclaration() && !GV->hasNotBeenReadFromBitcode());
diff --git a/lib/Target/X86/AsmPrinter/X86ATTAsmPrinter.cpp b/lib/Target/X86/AsmPrinter/X86ATTAsmPrinter.cpp
index 66319c39816..d5cb8bd13ca 100644
--- a/lib/Target/X86/AsmPrinter/X86ATTAsmPrinter.cpp
+++ b/lib/Target/X86/AsmPrinter/X86ATTAsmPrinter.cpp
@@ -391,6 +391,8 @@ void X86ATTAsmPrinter::printOperand(const MachineInstr *MI, unsigned OpNo,
             FnStubs.insert(Name);
             printSuffixedName(Name, "$stub");
           }
+        } else if (GV->hasHiddenVisibility()) {
+          O << Name;
         } else {
           GVStubs.insert(Name);
           printSuffixedName(Name, "$non_lazy_ptr");
diff --git a/lib/Target/X86/X86Subtarget.cpp b/lib/Target/X86/X86Subtarget.cpp
index c17f2dc6825..0e791324d38 100644
--- a/lib/Target/X86/X86Subtarget.cpp
+++ b/lib/Target/X86/X86Subtarget.cpp
@@ -40,6 +40,9 @@ bool X86Subtarget::GVRequiresExtraLoad(const GlobalValue* GV,
   if (TM.getRelocationModel() != Reloc::Static &&
       TM.getCodeModel() != CodeModel::Large) {
     if (isTargetDarwin()) {
+      if (GV->hasHiddenVisibility())
+        // Extra load is not needed for symbols with hidden visibility.
+        return false;
       return (!isDirectCall &&
               (GV->hasWeakLinkage() || GV->hasLinkOnceLinkage() ||
                GV->hasCommonLinkage() ||
diff --git a/test/CodeGen/X86/hidden-vis-2.ll b/test/CodeGen/X86/hidden-vis-2.ll
new file mode 100644
index 00000000000..e000547f44f
--- /dev/null
+++ b/test/CodeGen/X86/hidden-vis-2.ll
@@ -0,0 +1,10 @@
+; RUN: llvm-as < %s | llc -mtriple=i386-apple-darwin9   | grep mov | count 1
+; RUN: llvm-as < %s | llc -mtriple=x86_64-apple-darwin9 | not grep GOT
+
+@x = weak hidden global i32 0		; <i32*> [#uses=1]
+
+define i32 @t() nounwind readonly {
+entry:
+	%0 = load i32* @x, align 4		; <i32> [#uses=1]
+	ret i32 %0
+}