From: Sanjiv Gupta <sanjiv.gupta@microchip.com>
Date: Tue, 3 Feb 2009 18:07:49 +0000 (+0000)
Subject: Targets that don't have stack use global address space for parameters.
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=45206ecf708bf03b04db07c2476b9f862127a8b1;p=clang

Targets that don't have stack use global address space for parameters.
Specify external linkage for such globals so that llvm optimizer do
not assume there values initialized as zero.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@63636 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/CGDecl.cpp b/lib/CodeGen/CGDecl.cpp
index 6774f33337..898c1bfd80 100644
--- a/lib/CodeGen/CGDecl.cpp
+++ b/lib/CodeGen/CGDecl.cpp
@@ -77,7 +77,9 @@ void CodeGenFunction::EmitBlockVarDecl(const VarDecl &D) {
 llvm::GlobalValue *
 CodeGenFunction::GenerateStaticBlockVarDecl(const VarDecl &D,
                                             bool NoInit,
-                                            const char *Separator) {
+                                            const char *Separator,
+                                            llvm::GlobalValue
+					    	::LinkageTypes Linkage) {
   QualType Ty = D.getType();
   assert(Ty->isConstantSizeType() && "VLAs can't be static");
   
@@ -108,7 +110,7 @@ CodeGenFunction::GenerateStaticBlockVarDecl(const VarDecl &D,
 
   llvm::GlobalValue *GV =
     new llvm::GlobalVariable(Init->getType(), false,
-                             llvm::GlobalValue::InternalLinkage,
+                             Linkage,
                              Init, ContextName + Separator +D.getNameAsString(),
                              &CGM.getModule(), 0, Ty.getAddressSpace());
 
@@ -120,7 +122,9 @@ void CodeGenFunction::EmitStaticBlockVarDecl(const VarDecl &D) {
   llvm::Value *&DMEntry = LocalDeclMap[&D];
   assert(DMEntry == 0 && "Decl already exists in localdeclmap!");
   
-  llvm::GlobalValue *GV = GenerateStaticBlockVarDecl(D, false, ".");
+  llvm::GlobalValue *GV;
+  GV = GenerateStaticBlockVarDecl(D, false, ".",
+                                  llvm::GlobalValue::InternalLinkage);
 
   if (const AnnotateAttr *AA = D.getAttr<AnnotateAttr>()) {
     SourceManager &SM = CGM.getContext().getSourceManager();
@@ -166,7 +170,9 @@ void CodeGenFunction::EmitLocalBlockVarDecl(const VarDecl &D) {
       // Targets that don't support recursion emit locals as globals.
       const char *Class =
         D.getStorageClass() == VarDecl::Register ? ".reg." : ".auto.";
-      DeclPtr = GenerateStaticBlockVarDecl(D, true, Class);
+      DeclPtr = GenerateStaticBlockVarDecl(D, true, Class, 
+                                           llvm::GlobalValue
+                                           ::InternalLinkage);
     }
     
     if (Ty->isVariablyModifiedType())
@@ -232,7 +238,11 @@ void CodeGenFunction::EmitParmDecl(const VarDecl &D, llvm::Value *Arg) {
     // Variable sized values always are passed by-reference.
     DeclPtr = Arg;
   } else if (Target.useGlobalsForAutomaticVariables()) {
-    DeclPtr = GenerateStaticBlockVarDecl(D, true, ".arg.");
+    // Targets that don't have stack use global address space for parameters.
+    // Specify external linkage for such globals so that llvm optimizer do
+    // not assume there values initialized as zero.
+    DeclPtr = GenerateStaticBlockVarDecl(D, true, ".arg.",
+                                         llvm::GlobalValue::ExternalLinkage);
   } else {
     // A fixed sized single-value variable becomes an alloca in the entry block.
     const llvm::Type *LTy = ConvertType(Ty);
diff --git a/lib/CodeGen/CodeGenFunction.h b/lib/CodeGen/CodeGenFunction.h
index 1605e2a31d..31b2c4e4e4 100644
--- a/lib/CodeGen/CodeGenFunction.h
+++ b/lib/CodeGen/CodeGenFunction.h
@@ -627,9 +627,11 @@ public:
 
   /// GenerateStaticBlockVarDecl - return the the static
   /// declaration of local variable. 
-  llvm::GlobalValue *GenerateStaticBlockVarDecl(const VarDecl &D,
-                                                bool NoInit,
-                                                const char *Separator);
+  llvm::GlobalValue * GenerateStaticBlockVarDecl(const VarDecl &D,
+                                                 bool NoInit,
+                                                 const char *Separator,
+                                                 llvm::GlobalValue
+                                                 ::LinkageTypes Linkage);
 
   // GenerateStaticCXXBlockVarDecl - return the static declaration of
   // a local variable. Performs initialization of the variable if necessary.