[llvm-commits] [llvm] r137650 - in /llvm/trunk/lib/Analysis: AliasAnalysis.cpp LoopDependenceAnalysis.cpp MemDepPrinter.cpp MemoryDependenceAnalysis.cpp
Eli Friedman
eli.friedman at gmail.com
Mon Aug 15 13:54:19 PDT 2011
Author: efriedma
Date: Mon Aug 15 15:54:19 2011
New Revision: 137650
URL: http://llvm.org/viewvc/llvm-project?rev=137650&view=rev
Log:
Misc analysis passes that need to be aware of atomic load/store.
Modified:
llvm/trunk/lib/Analysis/AliasAnalysis.cpp
llvm/trunk/lib/Analysis/LoopDependenceAnalysis.cpp
llvm/trunk/lib/Analysis/MemDepPrinter.cpp
llvm/trunk/lib/Analysis/MemoryDependenceAnalysis.cpp
Modified: llvm/trunk/lib/Analysis/AliasAnalysis.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/AliasAnalysis.cpp?rev=137650&r1=137649&r2=137650&view=diff
==============================================================================
--- llvm/trunk/lib/Analysis/AliasAnalysis.cpp (original)
+++ llvm/trunk/lib/Analysis/AliasAnalysis.cpp Mon Aug 15 15:54:19 2011
@@ -268,8 +268,8 @@
AliasAnalysis::ModRefResult
AliasAnalysis::getModRefInfo(const LoadInst *L, const Location &Loc) {
- // Be conservative in the face of volatile.
- if (L->isVolatile())
+ // Be conservative in the face of volatile/atomic.
+ if (!L->isUnordered())
return ModRef;
// If the load address doesn't alias the given address, it doesn't read
@@ -283,8 +283,8 @@
AliasAnalysis::ModRefResult
AliasAnalysis::getModRefInfo(const StoreInst *S, const Location &Loc) {
- // Be conservative in the face of volatile.
- if (S->isVolatile())
+ // Be conservative in the face of volatile/atomic.
+ if (!S->isUnordered())
return ModRef;
// If the store address cannot alias the pointer in question, then the
Modified: llvm/trunk/lib/Analysis/LoopDependenceAnalysis.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/LoopDependenceAnalysis.cpp?rev=137650&r1=137649&r2=137650&view=diff
==============================================================================
--- llvm/trunk/lib/Analysis/LoopDependenceAnalysis.cpp (original)
+++ llvm/trunk/lib/Analysis/LoopDependenceAnalysis.cpp Mon Aug 15 15:54:19 2011
@@ -76,7 +76,13 @@
}
static bool IsLoadOrStoreInst(Value *I) {
- return isa<LoadInst>(I) || isa<StoreInst>(I);
+ // Returns true if the load or store can be analyzed. Atomic and volatile
+ // operations have properties which this analysis does not understand.
+ if (LoadInst *LI = dyn_cast<LoadInst>(I))
+ return LI->isUnordered();
+ else if (StoreInst *SI = dyn_cast<StoreInst>(I))
+ return SI->isUnordered();
+ return false;
}
static Value *GetPointerOperand(Value *I) {
Modified: llvm/trunk/lib/Analysis/MemDepPrinter.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/MemDepPrinter.cpp?rev=137650&r1=137649&r2=137650&view=diff
==============================================================================
--- llvm/trunk/lib/Analysis/MemDepPrinter.cpp (original)
+++ llvm/trunk/lib/Analysis/MemDepPrinter.cpp Mon Aug 15 15:54:19 2011
@@ -102,12 +102,21 @@
} else {
SmallVector<NonLocalDepResult, 4> NLDI;
if (LoadInst *LI = dyn_cast<LoadInst>(Inst)) {
- // FIXME: Volatile is not handled properly here.
+ if (!LI->isUnordered()) {
+ // FIXME: Handle atomic/volatile loads.
+ Deps[Inst].insert(std::make_pair(InstAndClobberFlag(0, false),
+ static_cast<BasicBlock *>(0)));
+ continue;
+ }
AliasAnalysis::Location Loc = AA.getLocation(LI);
- MDA.getNonLocalPointerDependency(Loc, !LI->isVolatile(),
- LI->getParent(), NLDI);
+ MDA.getNonLocalPointerDependency(Loc, true, LI->getParent(), NLDI);
} else if (StoreInst *SI = dyn_cast<StoreInst>(Inst)) {
- // FIXME: Volatile is not handled properly here.
+ if (!LI->isUnordered()) {
+ // FIXME: Handle atomic/volatile stores.
+ Deps[Inst].insert(std::make_pair(InstAndClobberFlag(0, false),
+ static_cast<BasicBlock *>(0)));
+ continue;
+ }
AliasAnalysis::Location Loc = AA.getLocation(SI);
MDA.getNonLocalPointerDependency(Loc, false, SI->getParent(), NLDI);
} else if (VAArgInst *VI = dyn_cast<VAArgInst>(Inst)) {
Modified: llvm/trunk/lib/Analysis/MemoryDependenceAnalysis.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/MemoryDependenceAnalysis.cpp?rev=137650&r1=137649&r2=137650&view=diff
==============================================================================
--- llvm/trunk/lib/Analysis/MemoryDependenceAnalysis.cpp (original)
+++ llvm/trunk/lib/Analysis/MemoryDependenceAnalysis.cpp Mon Aug 15 15:54:19 2011
@@ -120,21 +120,27 @@
AliasAnalysis::Location &Loc,
AliasAnalysis *AA) {
if (const LoadInst *LI = dyn_cast<LoadInst>(Inst)) {
- if (LI->isVolatile()) {
- Loc = AliasAnalysis::Location();
+ if (LI->isUnordered()) {
+ Loc = AA->getLocation(LI);
+ return AliasAnalysis::Ref;
+ } else if (LI->getOrdering() == Monotonic) {
+ Loc = AA->getLocation(LI);
return AliasAnalysis::ModRef;
}
- Loc = AA->getLocation(LI);
- return AliasAnalysis::Ref;
+ Loc = AliasAnalysis::Location();
+ return AliasAnalysis::ModRef;
}
if (const StoreInst *SI = dyn_cast<StoreInst>(Inst)) {
- if (SI->isVolatile()) {
- Loc = AliasAnalysis::Location();
+ if (SI->isUnordered()) {
+ Loc = AA->getLocation(SI);
+ return AliasAnalysis::Mod;
+ } else if (SI->getOrdering() == Monotonic) {
+ Loc = AA->getLocation(SI);
return AliasAnalysis::ModRef;
}
- Loc = AA->getLocation(SI);
- return AliasAnalysis::Mod;
+ Loc = AliasAnalysis::Location();
+ return AliasAnalysis::ModRef;
}
if (const VAArgInst *V = dyn_cast<VAArgInst>(Inst)) {
@@ -270,8 +276,8 @@
getLoadLoadClobberFullWidthSize(const Value *MemLocBase, int64_t MemLocOffs,
unsigned MemLocSize, const LoadInst *LI,
const TargetData &TD) {
- // We can only extend non-volatile integer loads.
- if (!isa<IntegerType>(LI->getType()) || LI->isVolatile()) return 0;
+ // We can only extend simple integer loads.
+ if (!isa<IntegerType>(LI->getType()) || !LI->isSimple()) return 0;
// Get the base of this load.
int64_t LIOffs = 0;
@@ -369,6 +375,11 @@
// Values depend on loads if the pointers are must aliased. This means that
// a load depends on another must aliased load from the same value.
if (LoadInst *LI = dyn_cast<LoadInst>(Inst)) {
+ // Atomic loads have complications involved.
+ // FIXME: This is overly conservative.
+ if (!LI->isUnordered())
+ return MemDepResult::getClobber(LI);
+
AliasAnalysis::Location LoadLoc = AA->getLocation(LI);
// If we found a pointer, check if it could be the same as our pointer.
@@ -424,6 +435,11 @@
}
if (StoreInst *SI = dyn_cast<StoreInst>(Inst)) {
+ // Atomic stores have complications involved.
+ // FIXME: This is overly conservative.
+ if (!SI->isUnordered())
+ return MemDepResult::getClobber(SI);
+
// If alias analysis can tell that this store is guaranteed to not modify
// the query pointer, ignore it. Use getModRefInfo to handle cases where
// the query pointer points to constant memory etc.
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