From 85bb54f96421461aaafcde83b6302530179337e9 Mon Sep 17 00:00:00 2001
From: Evan Phoenix <evan@fallingsnow.net>
Date: Thu, 4 Feb 2010 19:56:59 +0000
Subject: [PATCH] Disable external stubs for X86-32 and X86-64

Instruction selection for X86 now can choose an instruction
sequence that will fit any address of any symbol, no matter
the pointer width. X86-64 uses a mov+call-via-reg sequence
for this.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95323 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/llvm/CodeGen/MachineRelocation.h | 5 +++--
 lib/Target/X86/X86CodeEmitter.cpp        | 9 ++++++++-
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/include/llvm/CodeGen/MachineRelocation.h b/include/llvm/CodeGen/MachineRelocation.h
index 1c15fab532d..c316785dd11 100644
--- a/include/llvm/CodeGen/MachineRelocation.h
+++ b/include/llvm/CodeGen/MachineRelocation.h
@@ -138,14 +138,15 @@ public:
   ///
   static MachineRelocation getExtSym(uintptr_t offset, unsigned RelocationType, 
                                      const char *ES, intptr_t cst = 0,
-                                     bool GOTrelative = 0) {
+                                     bool GOTrelative = 0,
+                                     bool NeedStub = true) {
     assert((RelocationType & ~63) == 0 && "Relocation type too large!");
     MachineRelocation Result;
     Result.Offset = offset;
     Result.ConstantVal = cst;
     Result.TargetReloType = RelocationType;
     Result.AddrType = isExtSym;
-    Result.MayNeedFarStub = true;
+    Result.MayNeedFarStub = NeedStub;
     Result.GOTRelative = GOTrelative;
     Result.TargetResolve = false;
     Result.Target.ExtSym = ES;
diff --git a/lib/Target/X86/X86CodeEmitter.cpp b/lib/Target/X86/X86CodeEmitter.cpp
index b65d23e9651..a026392d4cd 100644
--- a/lib/Target/X86/X86CodeEmitter.cpp
+++ b/lib/Target/X86/X86CodeEmitter.cpp
@@ -191,8 +191,15 @@ template<class CodeEmitter>
 void Emitter<CodeEmitter>::emitExternalSymbolAddress(const char *ES,
                                                      unsigned Reloc) {
   intptr_t RelocCST = (Reloc == X86::reloc_picrel_word) ? PICBaseOffset : 0;
+
+  // X86 never needs stubs because instruction selection will always pick
+  // an instruction sequence that is large enough to hold any address
+  // to a symbol.
+  // (see X86ISelLowering.cpp, near 2039: X86TargetLowering::LowerCall)
+  bool NeedStub = false;
   MCE.addRelocation(MachineRelocation::getExtSym(MCE.getCurrentPCOffset(),
-                                                 Reloc, ES, RelocCST));
+                                                 Reloc, ES, RelocCST,
+                                                 0, NeedStub));
   if (Reloc == X86::reloc_absolute_dword)
     MCE.emitDWordLE(0);
   else