[Statepoints] Refactor GCRelocateOperands into an intrinsic wrapper. NFC.

Summary:
This commit renames GCRelocateOperands to GCRelocateInst and makes it an
intrinsic wrapper, similar to e.g. MemCpyInst.  Also, all users of
GCRelocateOperands were changed to use the new intrinsic wrapper instead.

Reviewers: sanjoy, reames

Subscribers: reames, sanjoy, llvm-commits

Differential Revision: http://reviews.llvm.org/D15762

llvm-svn: 256811

1 files changed, 20 insertions, 25 deletions

diff --git a/llvm/lib/CodeGen/CodeGenPrepare.cpp b/llvm/lib/CodeGen/CodeGenPrepare.cpp
index 4120b454451..6fbdea84c10 100644
--- a/llvm/lib/CodeGen/CodeGenPrepare.cpp
+++ b/llvm/lib/CodeGen/CodeGenPrepare.cpp
@@ -532,19 +532,17 @@ void CodeGenPrepare::eliminateMostlyEmptyBlock(BasicBlock *BB) {
 // Computes a map of base pointer relocation instructions to corresponding
 // derived pointer relocation instructions given a vector of all relocate calls
 static void computeBaseDerivedRelocateMap(
-    const SmallVectorImpl<User *> &AllRelocateCalls,
-    DenseMap<IntrinsicInst *, SmallVector<IntrinsicInst *, 2>> &
-        RelocateInstMap) {
+    const SmallVectorImpl<GCRelocateInst *> &AllRelocateCalls,
+    DenseMap<GCRelocateInst *, SmallVector<GCRelocateInst *, 2>>
+        &RelocateInstMap) {
   // Collect information in two maps: one primarily for locating the base object
   // while filling the second map; the second map is the final structure holding
   // a mapping between Base and corresponding Derived relocate calls
-  DenseMap<std::pair<unsigned, unsigned>, IntrinsicInst *> RelocateIdxMap;
-  for (auto &U : AllRelocateCalls) {
-    GCRelocateOperands ThisRelocate(U);
-    IntrinsicInst *I = cast<IntrinsicInst>(U);
-    auto K = std::make_pair(ThisRelocate.getBasePtrIndex(),
-                            ThisRelocate.getDerivedPtrIndex());
-    RelocateIdxMap.insert(std::make_pair(K, I));
+  DenseMap<std::pair<unsigned, unsigned>, GCRelocateInst *> RelocateIdxMap;
+  for (auto *ThisRelocate : AllRelocateCalls) {
+    auto K = std::make_pair(ThisRelocate->getBasePtrIndex(),
+                            ThisRelocate->getDerivedPtrIndex());
+    RelocateIdxMap.insert(std::make_pair(K, ThisRelocate));
   }
   for (auto &Item : RelocateIdxMap) {
     std::pair<unsigned, unsigned> Key = Item.first;
@@ -552,7 +550,7 @@ static void computeBaseDerivedRelocateMap(
       // Base relocation: nothing to insert
       continue;
 
-    IntrinsicInst *I = Item.second;
+    GCRelocateInst *I = Item.second;
     auto BaseKey = std::make_pair(Key.first, Key.first);
 
     // We're iterating over RelocateIdxMap so we cannot modify it.
@@ -585,16 +583,13 @@ static bool getGEPSmallConstantIntOffsetV(GetElementPtrInst *GEP,
 // Takes a RelocatedBase (base pointer relocation instruction) and Targets to
 // replace, computes a replacement, and affects it.
 static bool
-simplifyRelocatesOffABase(IntrinsicInst *RelocatedBase,
-                          const SmallVectorImpl<IntrinsicInst *> &Targets) {
+simplifyRelocatesOffABase(GCRelocateInst *RelocatedBase,
+                          const SmallVectorImpl<GCRelocateInst *> &Targets) {
   bool MadeChange = false;
-  for (auto &ToReplace : Targets) {
-    GCRelocateOperands MasterRelocate(RelocatedBase);
-    GCRelocateOperands ThisRelocate(ToReplace);
-
-    assert(ThisRelocate.getBasePtrIndex() == MasterRelocate.getBasePtrIndex() &&
+  for (GCRelocateInst *ToReplace : Targets) {
+    assert(ToReplace->getBasePtrIndex() == RelocatedBase->getBasePtrIndex() &&
            "Not relocating a derived object of the original base object");
-    if (ThisRelocate.getBasePtrIndex() == ThisRelocate.getDerivedPtrIndex()) {
+    if (ToReplace->getBasePtrIndex() == ToReplace->getDerivedPtrIndex()) {
       // A duplicate relocate call. TODO: coalesce duplicates.
       continue;
     }
@@ -607,8 +602,8 @@ simplifyRelocatesOffABase(IntrinsicInst *RelocatedBase,
       continue;
     }
 
-    Value *Base = ThisRelocate.getBasePtr();
-    auto Derived = dyn_cast<GetElementPtrInst>(ThisRelocate.getDerivedPtr());
+    Value *Base = ToReplace->getBasePtr();
+    auto Derived = dyn_cast<GetElementPtrInst>(ToReplace->getDerivedPtr());
     if (!Derived || Derived->getPointerOperand() != Base)
       continue;
 
@@ -686,12 +681,12 @@ simplifyRelocatesOffABase(IntrinsicInst *RelocatedBase,
 // %val = load %ptr'
 bool CodeGenPrepare::simplifyOffsetableRelocate(Instruction &I) {
   bool MadeChange = false;
-  SmallVector<User *, 2> AllRelocateCalls;
+  SmallVector<GCRelocateInst *, 2> AllRelocateCalls;
 
   for (auto *U : I.users())
-    if (isGCRelocate(dyn_cast<Instruction>(U)))
+    if (GCRelocateInst *Relocate = dyn_cast<GCRelocateInst>(U))
       // Collect all the relocate calls associated with a statepoint
-      AllRelocateCalls.push_back(U);
+      AllRelocateCalls.push_back(Relocate);
 
   // We need atleast one base pointer relocation + one derived pointer
   // relocation to mangle
@@ -700,7 +695,7 @@ bool CodeGenPrepare::simplifyOffsetableRelocate(Instruction &I) {
 
   // RelocateInstMap is a mapping from the base relocate instruction to the
   // corresponding derived relocate instructions
-  DenseMap<IntrinsicInst *, SmallVector<IntrinsicInst *, 2>> RelocateInstMap;
+  DenseMap<GCRelocateInst *, SmallVector<GCRelocateInst *, 2>> RelocateInstMap;
   computeBaseDerivedRelocateMap(AllRelocateCalls, RelocateInstMap);
   if (RelocateInstMap.empty())
     return false;