From 08fb05c3ac440979021f508bfee073359be46f7e Mon Sep 17 00:00:00 2001
From: Devang Patel <dpatel@apple.com>
Date: Wed, 25 Oct 2006 18:10:07 +0000
Subject: [PATCH] Supply alignment info to linker through LLVMSymbol.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@31181 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/llvm/LinkTimeOptimizer.h |  6 ++++--
 tools/lto/lto.cpp                | 18 ++++++++++++------
 2 files changed, 16 insertions(+), 8 deletions(-)

diff --git a/include/llvm/LinkTimeOptimizer.h b/include/llvm/LinkTimeOptimizer.h
index b52c578efea..c126bb23620 100644
--- a/include/llvm/LinkTimeOptimizer.h
+++ b/include/llvm/LinkTimeOptimizer.h
@@ -57,17 +57,19 @@ namespace llvm {
     void mayBeNotUsed();
 
     LLVMSymbol (enum LTOLinkageTypes lt, GlobalValue *g, const std::string &n, 
-                const std::string &m) : linkage(lt), gv(g), name(n), 
-                                        mangledName(m) {}
+                const std::string &m, int a) : linkage(lt), gv(g), name(n), 
+                                               mangledName(m), alignment(a) {}
 
     const char *getName() { return name.c_str(); }
     const char *getMangledName() { return mangledName.c_str(); }
+    int getAlignment() { return alignment; }
 
   private:
     enum LTOLinkageTypes linkage;
     GlobalValue *gv;
     std::string name;
     std::string mangledName;
+    int alignment;
   };
 
   class string_compare {
diff --git a/tools/lto/lto.cpp b/tools/lto/lto.cpp
index 5c507708b4a..b08b1a62dc3 100644
--- a/tools/lto/lto.cpp
+++ b/tools/lto/lto.cpp
@@ -36,6 +36,7 @@
 #include "llvm/Transforms/IPO.h"
 #include "llvm/Transforms/Scalar.h"
 #include "llvm/Analysis/LoadValueNumbering.h"
+#include "llvm/Support/MathExtras.h"
 #include "llvm/LinkTimeOptimizer.h"
 #include <fstream>
 #include <iostream>
@@ -149,8 +150,7 @@ LTO::readLLVMObjectFile(const std::string &InputFilename,
     return LTO_READ_FAILURE;
 
   // Collect Target info
-  if (!Target) 
-    getTarget(m);
+  getTarget(m);
 
   if (!Target)
     return LTO_READ_FAILURE;
@@ -166,8 +166,10 @@ LTO::readLLVMObjectFile(const std::string &InputFilename,
 
     if (!f->isExternal() && lt != LTOInternalLinkage
         && strncmp (f->getName().c_str(), "llvm.", 5)) {
+      int alignment = ( 16 > f->getAlignment() ? 16 : f->getAlignment());
       LLVMSymbol *newSymbol = new LLVMSymbol(lt, f, f->getName(), 
-                                             mangler.getValueName(f));
+                                             mangler.getValueName(f),
+                                             Log2_32(alignment));
       symbols[newSymbol->getMangledName()] = newSymbol;
       allSymbols[newSymbol->getMangledName()] = newSymbol;
     }
@@ -186,8 +188,10 @@ LTO::readLLVMObjectFile(const std::string &InputFilename,
     LTOLinkageTypes lt = getLTOLinkageType(v);
     if (!v->isExternal() && lt != LTOInternalLinkage
         && strncmp (v->getName().c_str(), "llvm.", 5)) {
+      const TargetData *TD = Target->getTargetData();
       LLVMSymbol *newSymbol = new LLVMSymbol(lt, v, v->getName(), 
-                                             mangler.getValueName(v));
+                                             mangler.getValueName(v),
+                                             TD->getPreferredAlignmentLog(v));
       symbols[newSymbol->getMangledName()] = newSymbol;
       allSymbols[newSymbol->getMangledName()] = newSymbol;
 
@@ -206,6 +210,9 @@ LTO::readLLVMObjectFile(const std::string &InputFilename,
 void
 LTO::getTarget (Module *M) {
 
+  if (Target)
+    return;
+
   std::string Err;
   const TargetMachineRegistry::Entry* March = 
     TargetMachineRegistry::getClosestStaticTargetForModule(*M, Err);
@@ -230,8 +237,7 @@ LTO::optimize(Module *M, std::ostream &Out,
   PassManager Passes;
   
   // Collect Target info
-  if (!Target) 
-    getTarget(M);
+  getTarget(M);
 
   if (!Target)
     return LTO_NO_TARGET;