AA metadata refactoring (introduce AAMDNodes)

In order to enable the preservation of noalias function parameter information
after inlining, and the representation of block-level __restrict__ pointer
information (etc.), additional kinds of aliasing metadata will be introduced.
This metadata needs to be carried around in AliasAnalysis::Location objects
(and MMOs at the SDAG level), and so we need to generalize the current scheme
(which is hard-coded to just one TBAA MDNode*).

This commit introduces only the necessary refactoring to allow for the
introduction of other aliasing metadata types, but does not actually introduce
any (that will come in a follow-up commit). What it does introduce is a new
AAMDNodes structure to hold all of the aliasing metadata nodes associated with
a particular memory-accessing instruction, and uses that structure instead of
the raw MDNode* in AliasAnalysis::Location, etc.

No functionality change intended.

llvm-svn: 213859

1 files changed, 30 insertions, 18 deletions

diff --git a/llvm/lib/Analysis/AliasAnalysis.cpp b/llvm/lib/Analysis/AliasAnalysis.cpp
index 8b8106b950a..8aee8b1aa33 100644
--- a/llvm/lib/Analysis/AliasAnalysis.cpp
+++ b/llvm/lib/Analysis/AliasAnalysis.cpp
@@ -252,35 +252,45 @@ AliasAnalysis::getModRefBehavior(const Function *F) {
 //===----------------------------------------------------------------------===//
 
 AliasAnalysis::Location AliasAnalysis::getLocation(const LoadInst *LI) {
+  AAMDNodes AATags;
+  LI->getAAMetadata(AATags);
+
   return Location(LI->getPointerOperand(),
-                  getTypeStoreSize(LI->getType()),
-                  LI->getMetadata(LLVMContext::MD_tbaa));
+                  getTypeStoreSize(LI->getType()), AATags);
 }
 
 AliasAnalysis::Location AliasAnalysis::getLocation(const StoreInst *SI) {
+  AAMDNodes AATags;
+  SI->getAAMetadata(AATags);
+
   return Location(SI->getPointerOperand(),
-                  getTypeStoreSize(SI->getValueOperand()->getType()),
-                  SI->getMetadata(LLVMContext::MD_tbaa));
+                  getTypeStoreSize(SI->getValueOperand()->getType()), AATags);
 }
 
 AliasAnalysis::Location AliasAnalysis::getLocation(const VAArgInst *VI) {
-  return Location(VI->getPointerOperand(),
-                  UnknownSize,
-                  VI->getMetadata(LLVMContext::MD_tbaa));
+  AAMDNodes AATags;
+  VI->getAAMetadata(AATags);
+
+  return Location(VI->getPointerOperand(), UnknownSize, AATags);
 }
 
 AliasAnalysis::Location
 AliasAnalysis::getLocation(const AtomicCmpXchgInst *CXI) {
+  AAMDNodes AATags;
+  CXI->getAAMetadata(AATags);
+
   return Location(CXI->getPointerOperand(),
                   getTypeStoreSize(CXI->getCompareOperand()->getType()),
-                  CXI->getMetadata(LLVMContext::MD_tbaa));
+                  AATags);
 }
 
 AliasAnalysis::Location
 AliasAnalysis::getLocation(const AtomicRMWInst *RMWI) {
+  AAMDNodes AATags;
+  RMWI->getAAMetadata(AATags);
+
   return Location(RMWI->getPointerOperand(),
-                  getTypeStoreSize(RMWI->getValOperand()->getType()),
-                  RMWI->getMetadata(LLVMContext::MD_tbaa));
+                  getTypeStoreSize(RMWI->getValOperand()->getType()), AATags);
 }
 
 AliasAnalysis::Location 
@@ -289,11 +299,12 @@ AliasAnalysis::getLocationForSource(const MemTransferInst *MTI) {
   if (ConstantInt *C = dyn_cast<ConstantInt>(MTI->getLength()))
     Size = C->getValue().getZExtValue();
 
-  // memcpy/memmove can have TBAA tags. For memcpy, they apply
+  // memcpy/memmove can have AA tags. For memcpy, they apply
   // to both the source and the destination.
-  MDNode *TBAATag = MTI->getMetadata(LLVMContext::MD_tbaa);
-
-  return Location(MTI->getRawSource(), Size, TBAATag);
+  AAMDNodes AATags;
+  MTI->getAAMetadata(AATags);
+  
+  return Location(MTI->getRawSource(), Size, AATags);
 }
 
 AliasAnalysis::Location 
@@ -302,11 +313,12 @@ AliasAnalysis::getLocationForDest(const MemIntrinsic *MTI) {
   if (ConstantInt *C = dyn_cast<ConstantInt>(MTI->getLength()))
     Size = C->getValue().getZExtValue();
 
-  // memcpy/memmove can have TBAA tags. For memcpy, they apply
+  // memcpy/memmove can have AA tags. For memcpy, they apply
   // to both the source and the destination.
-  MDNode *TBAATag = MTI->getMetadata(LLVMContext::MD_tbaa);
-  
-  return Location(MTI->getRawDest(), Size, TBAATag);
+  AAMDNodes AATags;
+  MTI->getMetadata(AATags);
+ 
+  return Location(MTI->getRawDest(), Size, AATags);
 }