X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FTransforms%2FIPO%2FConstantMerge.cpp;h=8ce7646621ff74c92a121397f45b51161dc5e506;hb=4556b1fe22ace7ced5cd37f171ca4418826d46c4;hp=d8fae8a4b2b906fbf2cfe0faadeac533a59ce66d;hpb=e15f421a9acd18ca71fed382ac09f7367b6a72f6;p=oota-llvm.git

diff --git a/lib/Transforms/IPO/ConstantMerge.cpp b/lib/Transforms/IPO/ConstantMerge.cpp
index d8fae8a4b2b..8ce7646621f 100644
--- a/lib/Transforms/IPO/ConstantMerge.cpp
+++ b/lib/Transforms/IPO/ConstantMerge.cpp
@@ -17,19 +17,21 @@
 //
 //===----------------------------------------------------------------------===//
 
-#define DEBUG_TYPE "constmerge"
 #include "llvm/Transforms/IPO.h"
-#include "llvm/Constants.h"
-#include "llvm/DerivedTypes.h"
-#include "llvm/Module.h"
-#include "llvm/Pass.h"
-#include "llvm/Target/TargetData.h"
 #include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/PointerIntPair.h"
 #include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/ADT/Statistic.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/DataLayout.h"
+#include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/Module.h"
+#include "llvm/IR/Operator.h"
+#include "llvm/Pass.h"
 using namespace llvm;
 
+#define DEBUG_TYPE "constmerge"
+
 STATISTIC(NumMerged, "Number of global constants merged");
 
 namespace {
@@ -41,7 +43,7 @@ namespace {
 
     // For this pass, process all of the globals in the module, eliminating
     // duplicate constants.
-    bool runOnModule(Module &M);
+    bool runOnModule(Module &M) override;
 
     // Return true iff we can determine the alignment of this global variable.
     bool hasKnownAlignment(GlobalVariable *GV) const;
@@ -50,7 +52,6 @@ namespace {
     // alignment to a concrete value.
     unsigned getAlignment(GlobalVariable *GV) const;
 
-    const TargetData *TD;
   };
 }
 
@@ -64,20 +65,20 @@ ModulePass *llvm::createConstantMergePass() { return new ConstantMerge(); }
 
 /// Find values that are marked as llvm.used.
 static void FindUsedValues(GlobalVariable *LLVMUsed,
-                           SmallPtrSet<const GlobalValue*, 8> &UsedValues) {
-  if (LLVMUsed == 0) return;
-  ConstantArray *Inits = dyn_cast<ConstantArray>(LLVMUsed->getInitializer());
-  if (Inits == 0) return;
-  
-  for (unsigned i = 0, e = Inits->getNumOperands(); i != e; ++i)
-    if (GlobalValue *GV = 
-        dyn_cast<GlobalValue>(Inits->getOperand(i)->stripPointerCasts()))
-      UsedValues.insert(GV);
+                           SmallPtrSetImpl<const GlobalValue*> &UsedValues) {
+  if (!LLVMUsed) return;
+  ConstantArray *Inits = cast<ConstantArray>(LLVMUsed->getInitializer());
+
+  for (unsigned i = 0, e = Inits->getNumOperands(); i != e; ++i) {
+    Value *Operand = Inits->getOperand(i)->stripPointerCastsNoFollowAliases();
+    GlobalValue *GV = cast<GlobalValue>(Operand);
+    UsedValues.insert(GV);
+  }
 }
 
 // True if A is better than B.
-static bool IsBetterCannonical(const GlobalVariable &A,
-                               const GlobalVariable &B) {
+static bool IsBetterCanonical(const GlobalVariable &A,
+                              const GlobalVariable &B) {
   if (!A.hasLocalLinkage() && B.hasLocalLinkage())
     return true;
 
@@ -87,28 +88,22 @@ static bool IsBetterCannonical(const GlobalVariable &A,
   return A.hasUnnamedAddr();
 }
 
-bool ConstantMerge::hasKnownAlignment(GlobalVariable *GV) const {
-  return TD || GV->getAlignment() != 0;
-}
-
 unsigned ConstantMerge::getAlignment(GlobalVariable *GV) const {
-  if (TD)
-    return TD->getPreferredAlignment(GV);
-  return GV->getAlignment();
+  unsigned Align = GV->getAlignment();
+  if (Align)
+    return Align;
+  return GV->getParent()->getDataLayout().getPreferredAlignment(GV);
 }
 
 bool ConstantMerge::runOnModule(Module &M) {
-  TD = getAnalysisIfAvailable<TargetData>();
 
   // Find all the globals that are marked "used".  These cannot be merged.
   SmallPtrSet<const GlobalValue*, 8> UsedGlobals;
   FindUsedValues(M.getGlobalVariable("llvm.used"), UsedGlobals);
   FindUsedValues(M.getGlobalVariable("llvm.compiler.used"), UsedGlobals);
-  
-  // Map unique <constants, has-unknown-alignment> pairs to globals.  We don't
-  // want to merge globals of unknown alignment with those of explicit
-  // alignment.  If we have TargetData, we always know the alignment.
-  DenseMap<PointerIntPair<Constant*, 1, bool>, GlobalVariable*> CMap;
+
+  // Map unique constants to globals.
+  DenseMap<Constant *, GlobalVariable *> CMap;
 
   // Replacements - This vector contains a list of replacements to perform.
   SmallVector<std::pair<GlobalVariable*, GlobalVariable*>, 32> Replacements;
@@ -150,13 +145,12 @@ bool ConstantMerge::runOnModule(Module &M) {
       Constant *Init = GV->getInitializer();
 
       // Check to see if the initializer is already known.
-      PointerIntPair<Constant*, 1, bool> Pair(Init, hasKnownAlignment(GV));
-      GlobalVariable *&Slot = CMap[Pair];
+      GlobalVariable *&Slot = CMap[Init];
 
       // If this is the first constant we find or if the old one is local,
       // replace with the current one. If the current is externally visible
       // it cannot be replace, but can be the canonical constant we merge with.
-      if (Slot == 0 || IsBetterCannonical(*GV, *Slot))
+      if (!Slot || IsBetterCanonical(*GV, *Slot))
         Slot = GV;
     }
 
@@ -182,8 +176,7 @@ bool ConstantMerge::runOnModule(Module &M) {
       Constant *Init = GV->getInitializer();
 
       // Check to see if the initializer is already known.
-      PointerIntPair<Constant*, 1, bool> Pair(Init, hasKnownAlignment(GV));
-      GlobalVariable *Slot = CMap[Pair];
+      GlobalVariable *Slot = CMap[Init];
 
       if (!Slot || Slot == GV)
         continue;
@@ -209,9 +202,9 @@ bool ConstantMerge::runOnModule(Module &M) {
       // Bump the alignment if necessary.
       if (Replacements[i].first->getAlignment() ||
           Replacements[i].second->getAlignment()) {
-        Replacements[i].second->setAlignment(std::max(
-            Replacements[i].first->getAlignment(),
-            Replacements[i].second->getAlignment()));
+        Replacements[i].second->setAlignment(
+            std::max(getAlignment(Replacements[i].first),
+                     getAlignment(Replacements[i].second)));
       }
 
       // Eliminate any uses of the dead global.