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-rw-r--r--contrib/llvm/tools/clang/lib/CodeGen/CGValue.h109
1 files changed, 69 insertions, 40 deletions
diff --git a/contrib/llvm/tools/clang/lib/CodeGen/CGValue.h b/contrib/llvm/tools/clang/lib/CodeGen/CGValue.h
index 4d0b841..489e600 100644
--- a/contrib/llvm/tools/clang/lib/CodeGen/CGValue.h
+++ b/contrib/llvm/tools/clang/lib/CodeGen/CGValue.h
@@ -337,65 +337,90 @@ class AggValueSlot {
// Qualifiers
Qualifiers Quals;
+
+ /// DestructedFlag - This is set to true if some external code is
+ /// responsible for setting up a destructor for the slot. Otherwise
+ /// the code which constructs it should push the appropriate cleanup.
+ bool DestructedFlag : 1;
+
+ /// ObjCGCFlag - This is set to true if writing to the memory in the
+ /// slot might require calling an appropriate Objective-C GC
+ /// barrier. The exact interaction here is unnecessarily mysterious.
+ bool ObjCGCFlag : 1;
- // Associated flags.
- bool LifetimeFlag : 1;
- bool RequiresGCollection : 1;
-
- /// IsZeroed - This is set to true if the destination is known to be zero
- /// before the assignment into it. This means that zero fields don't need to
- /// be set.
- bool IsZeroed : 1;
+ /// ZeroedFlag - This is set to true if the memory in the slot is
+ /// known to be zero before the assignment into it. This means that
+ /// zero fields don't need to be set.
+ bool ZeroedFlag : 1;
+
+ /// AliasedFlag - This is set to true if the slot might be aliased
+ /// and it's not undefined behavior to access it through such an
+ /// alias. Note that it's always undefined behavior to access a C++
+ /// object that's under construction through an alias derived from
+ /// outside the construction process.
+ ///
+ /// This flag controls whether calls that produce the aggregate
+ /// value may be evaluated directly into the slot, or whether they
+ /// must be evaluated into an unaliased temporary and then memcpy'ed
+ /// over. Since it's invalid in general to memcpy a non-POD C++
+ /// object, it's important that this flag never be set when
+ /// evaluating an expression which constructs such an object.
+ bool AliasedFlag : 1;
public:
+ enum IsAliased_t { IsNotAliased, IsAliased };
+ enum IsDestructed_t { IsNotDestructed, IsDestructed };
+ enum IsZeroed_t { IsNotZeroed, IsZeroed };
+ enum NeedsGCBarriers_t { DoesNotNeedGCBarriers, NeedsGCBarriers };
+
/// ignored - Returns an aggregate value slot indicating that the
/// aggregate value is being ignored.
static AggValueSlot ignored() {
AggValueSlot AV;
AV.Addr = 0;
AV.Quals = Qualifiers();
- AV.LifetimeFlag = AV.RequiresGCollection = AV.IsZeroed =0;
+ AV.DestructedFlag = AV.ObjCGCFlag = AV.ZeroedFlag = AV.AliasedFlag = false;
return AV;
}
/// forAddr - Make a slot for an aggregate value.
///
- /// \param Volatile - true if the slot should be volatile-initialized
- ///
- /// \param Qualifiers - The qualifiers that dictate how the slot
- /// should be initialied. Only 'volatile' and the Objective-C
- /// lifetime qualifiers matter.
+ /// \param quals - The qualifiers that dictate how the slot should
+ /// be initialied. Only 'volatile' and the Objective-C lifetime
+ /// qualifiers matter.
///
- /// \param LifetimeExternallyManaged - true if the slot's lifetime
- /// is being externally managed; false if a destructor should be
- /// registered for any temporaries evaluated into the slot
- /// \param RequiresGCollection - true if the slot is located
+ /// \param isDestructed - true if something else is responsible
+ /// for calling destructors on this object
+ /// \param needsGC - true if the slot is potentially located
/// somewhere that ObjC GC calls should be emitted for
- static AggValueSlot forAddr(llvm::Value *Addr, Qualifiers Quals,
- bool LifetimeExternallyManaged,
- bool RequiresGCollection = false,
- bool IsZeroed = false) {
+ static AggValueSlot forAddr(llvm::Value *addr, Qualifiers quals,
+ IsDestructed_t isDestructed,
+ NeedsGCBarriers_t needsGC,
+ IsAliased_t isAliased,
+ IsZeroed_t isZeroed = IsNotZeroed) {
AggValueSlot AV;
- AV.Addr = Addr;
- AV.Quals = Quals;
- AV.LifetimeFlag = LifetimeExternallyManaged;
- AV.RequiresGCollection = RequiresGCollection;
- AV.IsZeroed = IsZeroed;
+ AV.Addr = addr;
+ AV.Quals = quals;
+ AV.DestructedFlag = isDestructed;
+ AV.ObjCGCFlag = needsGC;
+ AV.ZeroedFlag = isZeroed;
+ AV.AliasedFlag = isAliased;
return AV;
}
- static AggValueSlot forLValue(LValue LV, bool LifetimeExternallyManaged,
- bool RequiresGCollection = false,
- bool IsZeroed = false) {
+ static AggValueSlot forLValue(LValue LV, IsDestructed_t isDestructed,
+ NeedsGCBarriers_t needsGC,
+ IsAliased_t isAliased,
+ IsZeroed_t isZeroed = IsNotZeroed) {
return forAddr(LV.getAddress(), LV.getQuals(),
- LifetimeExternallyManaged, RequiresGCollection, IsZeroed);
+ isDestructed, needsGC, isAliased, isZeroed);
}
- bool isLifetimeExternallyManaged() const {
- return LifetimeFlag;
+ IsDestructed_t isExternallyDestructed() const {
+ return IsDestructed_t(DestructedFlag);
}
- void setLifetimeExternallyManaged(bool Managed = true) {
- LifetimeFlag = Managed;
+ void setExternallyDestructed(bool destructed = true) {
+ DestructedFlag = destructed;
}
Qualifiers getQualifiers() const { return Quals; }
@@ -408,8 +433,8 @@ public:
return Quals.getObjCLifetime();
}
- bool requiresGCollection() const {
- return RequiresGCollection;
+ NeedsGCBarriers_t requiresGCollection() const {
+ return NeedsGCBarriers_t(ObjCGCFlag);
}
llvm::Value *getAddr() const {
@@ -420,13 +445,17 @@ public:
return Addr == 0;
}
+ IsAliased_t isPotentiallyAliased() const {
+ return IsAliased_t(AliasedFlag);
+ }
+
RValue asRValue() const {
return RValue::getAggregate(getAddr(), isVolatile());
}
- void setZeroed(bool V = true) { IsZeroed = V; }
- bool isZeroed() const {
- return IsZeroed;
+ void setZeroed(bool V = true) { ZeroedFlag = V; }
+ IsZeroed_t isZeroed() const {
+ return IsZeroed_t(ZeroedFlag);
}
};
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