Misc fixes for atomics. Biggest fix is doing alignment correctly for _Atomic types.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@142002 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/AST/ASTContext.cpp b/lib/AST/ASTContext.cpp
index b625655..ae96dfd 100644
--- a/lib/AST/ASTContext.cpp
+++ b/lib/AST/ASTContext.cpp
@@ -1064,13 +1064,25 @@
}
case Type::Atomic: {
- // FIXME: The alignment needs to be "fixed".
- return getTypeInfo(cast<AtomicType>(T)->getValueType());
+ std::pair<uint64_t, unsigned> Info
+ = getTypeInfo(cast<AtomicType>(T)->getValueType());
+ Width = Info.first;
+ Align = Info.second;
+ if (Width != 0 && Width <= Target->getMaxAtomicPromoteWidth() &&
+ llvm::isPowerOf2_64(Width)) {
+ // We can potentially perform lock-free atomic operations for this
+ // type; promote the alignment appropriately.
+ // FIXME: We could potentially promote the width here as well...
+ // is that worthwhile? (Non-struct atomic types generally have
+ // power-of-two size anyway, but structs might not. Requires a bit
+ // of implementation work to make sure we zero out the extra bits.)
+ Align = static_cast<unsigned>(Width);
+ }
}
}
- assert(Align && (Align & (Align-1)) == 0 && "Alignment must be power of 2");
+ assert(llvm::isPowerOf2_32(Align) && "Alignment must be power of 2");
return std::make_pair(Width, Align);
}
diff --git a/lib/AST/StmtProfile.cpp b/lib/AST/StmtProfile.cpp
index df49e84..214378a 100644
--- a/lib/AST/StmtProfile.cpp
+++ b/lib/AST/StmtProfile.cpp
@@ -470,6 +470,7 @@
void StmtProfiler::VisitAtomicExpr(const AtomicExpr *S) {
VisitExpr(S);
+ ID.AddInteger(S->getOp());
}
static Stmt::StmtClass DecodeOperatorCall(const CXXOperatorCallExpr *S,
diff --git a/lib/Basic/TargetInfo.cpp b/lib/Basic/TargetInfo.cpp
index d5dcf06..a9285e6 100644
--- a/lib/Basic/TargetInfo.cpp
+++ b/lib/Basic/TargetInfo.cpp
@@ -42,6 +42,7 @@
LongDoubleAlign = 64;
LargeArrayMinWidth = 0;
LargeArrayAlign = 0;
+ MaxAtomicPromoteWidth = MaxAtomicInlineWidth = 0;
SizeType = UnsignedLong;
PtrDiffType = SignedLong;
IntMaxType = SignedLongLong;
diff --git a/lib/Basic/Targets.cpp b/lib/Basic/Targets.cpp
index 648ed73..889518b 100644
--- a/lib/Basic/Targets.cpp
+++ b/lib/Basic/Targets.cpp
@@ -1984,6 +1984,11 @@
RealTypeUsesObjCFPRet = ((1 << TargetInfo::Float) |
(1 << TargetInfo::Double) |
(1 << TargetInfo::LongDouble));
+
+ // x86-32 has atomics up to 8 bytes
+ // FIXME: Check that we actually have cmpxchg8b before setting
+ // MaxAtomicInlineWidth. (cmpxchg8b is an i586 instruction.)
+ MaxAtomicPromoteWidth = MaxAtomicInlineWidth = 64;
}
virtual const char *getVAListDeclaration() const {
return "typedef char* __builtin_va_list;";
@@ -2219,6 +2224,12 @@
// Use fpret only for long double.
RealTypeUsesObjCFPRet = (1 << TargetInfo::LongDouble);
+
+ // x86-64 has atomics up to 16 bytes.
+ // FIXME: Once the backend is fixed, increase MaxAtomicInlineWidth to 128
+ // on CPUs with cmpxchg16b
+ MaxAtomicPromoteWidth = 128;
+ MaxAtomicInlineWidth = 64;
}
virtual const char *getVAListDeclaration() const {
return "typedef struct __va_list_tag {"
@@ -2391,6 +2402,10 @@
// ARM targets default to using the ARM C++ ABI.
CXXABI = CXXABI_ARM;
+
+ // ARM has atomics up to 8 bytes
+ // FIXME: Set MaxAtomicInlineWidth if we have the feature v6e
+ MaxAtomicPromoteWidth = 64;
}
virtual const char *getABI() const { return ABI.c_str(); }
virtual bool setABI(const std::string &Name) {
@@ -2708,6 +2723,9 @@
DarwinARMTargetInfo(const std::string& triple)
: DarwinTargetInfo<ARMTargetInfo>(triple) {
HasAlignMac68kSupport = true;
+ // iOS always has 64-bit atomic instructions.
+ // FIXME: This should be based off of the target features in ARMTargetInfo.
+ MaxAtomicInlineWidth = 64;
}
};
} // end anonymous namespace.
diff --git a/lib/CodeGen/CGExpr.cpp b/lib/CodeGen/CGExpr.cpp
index ad27506..bd4e553 100644
--- a/lib/CodeGen/CGExpr.cpp
+++ b/lib/CodeGen/CGExpr.cpp
@@ -2567,9 +2567,9 @@
uint64_t Size = sizeChars.getQuantity();
CharUnits alignChars = getContext().getTypeAlignInChars(AtomicTy);
unsigned Align = alignChars.getQuantity();
- // FIXME: Bound on Size should not be hardcoded.
- bool UseLibcall = (sizeChars != alignChars || !llvm::isPowerOf2_64(Size) ||
- Size > 8);
+ unsigned MaxInlineWidth =
+ getContext().getTargetInfo().getMaxAtomicInlineWidth();
+ bool UseLibcall = (Size != Align || Size > MaxInlineWidth);
llvm::Value *Ptr, *Order, *OrderFail = 0, *Val1 = 0, *Val2 = 0;
Ptr = EmitScalarExpr(E->getPtr());
@@ -2585,11 +2585,9 @@
// is not the same as adding 1 to a uintptr_t.
QualType Val1Ty = E->getVal1()->getType();
llvm::Value *Val1Scalar = EmitScalarExpr(E->getVal1());
- uint64_t PointeeIncAmt =
- getContext().getTypeSizeInChars(MemTy->getPointeeType()).getQuantity();
- llvm::Value *PointeeIncAmtVal =
- llvm::ConstantInt::get(Val1Scalar->getType(), PointeeIncAmt);
- Val1Scalar = Builder.CreateMul(Val1Scalar, PointeeIncAmtVal);
+ CharUnits PointeeIncAmt =
+ getContext().getTypeSizeInChars(MemTy->getPointeeType());
+ Val1Scalar = Builder.CreateMul(Val1Scalar, CGM.getSize(PointeeIncAmt));
Val1 = CreateMemTemp(Val1Ty, ".atomictmp");
EmitStoreOfScalar(Val1Scalar, MakeAddrLValue(Val1, Val1Ty));
} else if (E->getOp() != AtomicExpr::Load) {