Track volatile aggregate copies better. I'm hoping someone else will decide
how to get the backend to know that the operation is volatile.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@72348 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGExprAgg.cpp b/lib/CodeGen/CGExprAgg.cpp
index 3b78713..b37b7d2 100644
--- a/lib/CodeGen/CGExprAgg.cpp
+++ b/lib/CodeGen/CGExprAgg.cpp
@@ -144,7 +144,8 @@
// FIXME: Pass VolatileDest as well. I think we also need to merge volatile
// from the source as well, as we can't eliminate it if either operand
// is volatile, unless copy has volatile for both source and destination..
- CGF.EmitAggregateCopy(DestPtr, Src.getAggregateAddr(), E->getType());
+ CGF.EmitAggregateCopy(DestPtr, Src.getAggregateAddr(), E->getType(),
+ VolatileDest|Src.isVolatileQualified());
}
/// EmitFinalDestCopy - Perform the final copy to DestPtr, if desired.
@@ -484,7 +485,8 @@
}
void CodeGenFunction::EmitAggregateCopy(llvm::Value *DestPtr,
- llvm::Value *SrcPtr, QualType Ty) {
+ llvm::Value *SrcPtr, QualType Ty,
+ bool isVolatile) {
assert(!Ty->isAnyComplexType() && "Shouldn't happen for complex");
// Aggregate assignment turns into llvm.memcpy. This is almost valid per
@@ -520,7 +522,8 @@
// }
//
// either, we need to use a differnt call here, or the backend needs to be
- // taught to not do this.
+ // taught to not do this. We use isVolatile to indicate when either the
+ // source or the destination is volatile.
Builder.CreateCall4(CGM.getMemCpyFn(),
DestPtr, SrcPtr,
// TypeInfo.first describes size in bits.
diff --git a/lib/CodeGen/CodeGenFunction.h b/lib/CodeGen/CodeGenFunction.h
index 130bc36..9a9ca05 100644
--- a/lib/CodeGen/CodeGenFunction.h
+++ b/lib/CodeGen/CodeGenFunction.h
@@ -419,8 +419,12 @@
RValue EmitAnyExprToTemp(const Expr *E, llvm::Value *AggLoc = 0,
bool isAggLocVolatile = false);
+ /// EmitAggregateCopy - Emit an aggrate copy.
+ ///
+ /// \param isVolatile - True iff either the source or the destination is
+ /// volatile.
void EmitAggregateCopy(llvm::Value *DestPtr, llvm::Value *SrcPtr,
- QualType EltTy);
+ QualType EltTy, bool isVolatile=false);
void EmitAggregateClear(llvm::Value *DestPtr, QualType Ty);