[AA] Allow for flow-sensitive analyses.

All current analyses ignore the context. We make the argument mandatory
for analyses, but optional for the query interface.

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D136512

1 files changed, 13 insertions, 12 deletions

diff --git a/llvm/lib/Analysis/AliasAnalysis.cpp b/llvm/lib/Analysis/AliasAnalysis.cpp
index 73de6fa..9e24f6b 100644
--- a/llvm/lib/Analysis/AliasAnalysis.cpp
+++ b/llvm/lib/Analysis/AliasAnalysis.cpp
@@ -105,11 +105,12 @@ bool AAResults::invalidate(Function &F, const PreservedAnalyses &PA,
 AliasResult AAResults::alias(const MemoryLocation &LocA,
                              const MemoryLocation &LocB) {
   SimpleAAQueryInfo AAQIP(*this);
-  return alias(LocA, LocB, AAQIP);
+  return alias(LocA, LocB, AAQIP, nullptr);
 }
 
 AliasResult AAResults::alias(const MemoryLocation &LocA,
-                             const MemoryLocation &LocB, AAQueryInfo &AAQI) {
+                             const MemoryLocation &LocB, AAQueryInfo &AAQI,
+                             const Instruction *CtxI) {
   AliasResult Result = AliasResult::MayAlias;
 
   if (EnableAATrace) {
@@ -121,7 +122,7 @@ AliasResult AAResults::alias(const MemoryLocation &LocA,
 
   AAQI.Depth++;
   for (const auto &AA : AAs) {
-    Result = AA->alias(LocA, LocB, AAQI);
+    Result = AA->alias(LocA, LocB, AAQI, CtxI);
     if (Result != AliasResult::MayAlias)
       break;
   }
@@ -243,7 +244,7 @@ ModRefInfo AAResults::getModRefInfo(const CallBase *Call,
         continue;
       unsigned ArgIdx = I.index();
       MemoryLocation ArgLoc = MemoryLocation::getForArgument(Call, ArgIdx, TLI);
-      AliasResult ArgAlias = alias(ArgLoc, Loc, AAQI);
+      AliasResult ArgAlias = alias(ArgLoc, Loc, AAQI, Call);
       if (ArgAlias != AliasResult::NoAlias)
         AllArgsMask |= getArgModRefInfo(Call, ArgIdx);
     }
@@ -472,7 +473,7 @@ ModRefInfo AAResults::getModRefInfo(const LoadInst *L,
   // If the load address doesn't alias the given address, it doesn't read
   // or write the specified memory.
   if (Loc.Ptr) {
-    AliasResult AR = alias(MemoryLocation::get(L), Loc, AAQI);
+    AliasResult AR = alias(MemoryLocation::get(L), Loc, AAQI, L);
     if (AR == AliasResult::NoAlias)
       return ModRefInfo::NoModRef;
   }
@@ -488,7 +489,7 @@ ModRefInfo AAResults::getModRefInfo(const StoreInst *S,
     return ModRefInfo::ModRef;
 
   if (Loc.Ptr) {
-    AliasResult AR = alias(MemoryLocation::get(S), Loc, AAQI);
+    AliasResult AR = alias(MemoryLocation::get(S), Loc, AAQI, S);
     // If the store address cannot alias the pointer in question, then the
     // specified memory cannot be modified by the store.
     if (AR == AliasResult::NoAlias)
@@ -521,7 +522,7 @@ ModRefInfo AAResults::getModRefInfo(const VAArgInst *V,
                                     const MemoryLocation &Loc,
                                     AAQueryInfo &AAQI) {
   if (Loc.Ptr) {
-    AliasResult AR = alias(MemoryLocation::get(V), Loc, AAQI);
+    AliasResult AR = alias(MemoryLocation::get(V), Loc, AAQI, V);
     // If the va_arg address cannot alias the pointer in question, then the
     // specified memory cannot be accessed by the va_arg.
     if (AR == AliasResult::NoAlias)
@@ -570,7 +571,7 @@ ModRefInfo AAResults::getModRefInfo(const AtomicCmpXchgInst *CX,
     return ModRefInfo::ModRef;
 
   if (Loc.Ptr) {
-    AliasResult AR = alias(MemoryLocation::get(CX), Loc, AAQI);
+    AliasResult AR = alias(MemoryLocation::get(CX), Loc, AAQI, CX);
     // If the cmpxchg address does not alias the location, it does not access
     // it.
     if (AR == AliasResult::NoAlias)
@@ -588,7 +589,7 @@ ModRefInfo AAResults::getModRefInfo(const AtomicRMWInst *RMW,
     return ModRefInfo::ModRef;
 
   if (Loc.Ptr) {
-    AliasResult AR = alias(MemoryLocation::get(RMW), Loc, AAQI);
+    AliasResult AR = alias(MemoryLocation::get(RMW), Loc, AAQI, RMW);
     // If the atomicrmw address does not alias the location, it does not access
     // it.
     if (AR == AliasResult::NoAlias)
@@ -676,9 +677,9 @@ ModRefInfo AAResults::callCapturesBefore(const Instruction *I,
          !Call->isByValArgument(ArgNo)))
       continue;
 
-    AliasResult AR = alias(
-        MemoryLocation::getBeforeOrAfter(*CI),
-        MemoryLocation::getBeforeOrAfter(Object), AAQI);
+    AliasResult AR =
+        alias(MemoryLocation::getBeforeOrAfter(*CI),
+              MemoryLocation::getBeforeOrAfter(Object), AAQI, Call);
     // If this is a no-capture pointer argument, see if we can tell that it
     // is impossible to alias the pointer we're checking.  If not, we have to
     // assume that the call could touch the pointer, even though it doesn't