From: Silviu Baranga <silviu.baranga@arm.com>
Date: Mon, 7 Jan 2013 12:31:25 +0000 (+0000)
Subject: Make the MergeGlobals pass correctly handle the address space qualifiers of the globa... 
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=e97165901ee51216b22b808041b10febbb4afa5e;p=oota-llvm.git

Make the MergeGlobals pass correctly handle the address space qualifiers of the global variables. We partition the set of globals by their address space, and apply the same the trasnformation as before to merge them.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171730 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Transforms/Scalar/GlobalMerge.cpp b/lib/Transforms/Scalar/GlobalMerge.cpp
index d9ce74eb54c..1601a8d6466 100644
--- a/lib/Transforms/Scalar/GlobalMerge.cpp
+++ b/lib/Transforms/Scalar/GlobalMerge.cpp
@@ -76,7 +76,7 @@ namespace {
     const TargetLowering *TLI;
 
     bool doMerge(SmallVectorImpl<GlobalVariable*> &Globals,
-                 Module &M, bool isConst) const;
+                 Module &M, bool isConst, unsigned AddrSpace) const;
 
   public:
     static char ID;             // Pass identification, replacement for typeid.
@@ -118,7 +118,7 @@ INITIALIZE_PASS(GlobalMerge, "global-merge",
 
 
 bool GlobalMerge::doMerge(SmallVectorImpl<GlobalVariable*> &Globals,
-                             Module &M, bool isConst) const {
+                          Module &M, bool isConst, unsigned AddrSpace) const {
   const DataLayout *TD = TLI->getDataLayout();
 
   // FIXME: Infer the maximum possible offset depending on the actual users
@@ -150,7 +150,9 @@ bool GlobalMerge::doMerge(SmallVectorImpl<GlobalVariable*> &Globals,
     Constant *MergedInit = ConstantStruct::get(MergedTy, Inits);
     GlobalVariable *MergedGV = new GlobalVariable(M, MergedTy, isConst,
                                                   GlobalValue::InternalLinkage,
-                                                  MergedInit, "_MergedGlobals");
+                                                  MergedInit, "_MergedGlobals",
+                                                  0, GlobalVariable::NotThreadLocal,
+                                                  AddrSpace);
     for (size_t k = i; k < j; ++k) {
       Constant *Idx[2] = {
         ConstantInt::get(Int32Ty, 0),
@@ -169,7 +171,8 @@ bool GlobalMerge::doMerge(SmallVectorImpl<GlobalVariable*> &Globals,
 
 
 bool GlobalMerge::doInitialization(Module &M) {
-  SmallVector<GlobalVariable*, 16> Globals, ConstGlobals, BSSGlobals;
+  DenseMap<unsigned, SmallVector<GlobalVariable*, 16> > Globals, ConstGlobals,
+                                                        BSSGlobals;
   const DataLayout *TD = TLI->getDataLayout();
   unsigned MaxOffset = TLI->getMaximalGlobalOffset();
   bool Changed = false;
@@ -181,6 +184,11 @@ bool GlobalMerge::doInitialization(Module &M) {
     if (!I->hasLocalLinkage() || I->isThreadLocal() || I->hasSection())
       continue;
 
+    PointerType *PT = dyn_cast<PointerType>(I->getType());
+    assert(PT && "Global variable is not a pointer!");
+
+    unsigned AddressSpace = PT->getAddressSpace();
+
     // Ignore fancy-aligned globals for now.
     unsigned Alignment = TD->getPreferredAlignment(I);
     Type *Ty = I->getType()->getElementType();
@@ -195,18 +203,23 @@ bool GlobalMerge::doInitialization(Module &M) {
     if (TD->getTypeAllocSize(Ty) < MaxOffset) {
       if (TargetLoweringObjectFile::getKindForGlobal(I, TLI->getTargetMachine())
           .isBSSLocal())
-        BSSGlobals.push_back(I);
+        BSSGlobals[AddressSpace].push_back(I);
       else if (I->isConstant())
-        ConstGlobals.push_back(I);
+        ConstGlobals[AddressSpace].push_back(I);
       else
-        Globals.push_back(I);
+        Globals[AddressSpace].push_back(I);
     }
   }
 
-  if (Globals.size() > 1)
-    Changed |= doMerge(Globals, M, false);
-  if (BSSGlobals.size() > 1)
-    Changed |= doMerge(BSSGlobals, M, false);
+  for (DenseMap<unsigned, SmallVector<GlobalVariable*, 16> >::iterator
+       I = Globals.begin(), E = Globals.end(); I != E; ++I)
+    if (I->second.size() > 1)
+      Changed |= doMerge(I->second, M, false, I->first);
+
+  for (DenseMap<unsigned, SmallVector<GlobalVariable*, 16> >::iterator
+       I = BSSGlobals.begin(), E = BSSGlobals.end(); I != E; ++I)
+    if (I->second.size() > 1)
+      Changed |= doMerge(I->second, M, false, I->first);
 
   // FIXME: This currently breaks the EH processing due to way how the
   // typeinfo detection works. We might want to detect the TIs and ignore
diff --git a/test/CodeGen/ARM/global-merge-addrspace.ll b/test/CodeGen/ARM/global-merge-addrspace.ll
new file mode 100644
index 00000000000..0efa690bde2
--- /dev/null
+++ b/test/CodeGen/ARM/global-merge-addrspace.ll
@@ -0,0 +1,12 @@
+; RUN: llc < %s -mtriple=thumb-apple-darwin | FileCheck %s
+; Test the GlobalMerge pass. Check that the pass does not crash when using
+; multiple address spaces.
+
+; CHECK: _MergedGlobals:
+@g1 = internal addrspace(1) global i32 1
+@g2 = internal addrspace(1) global i32 2
+
+
+; CHECK: _MergedGlobals1:
+@g3 = internal addrspace(2) global i32 3
+@g4 = internal addrspace(2) global i32 4