[cfe-commits] r153733 - in /cfe/trunk: lib/CodeGen/CGCXXABI.cpp lib/CodeGen/CGCXXABI.h lib/CodeGen/CGDecl.cpp lib/CodeGen/CGDeclCXX.cpp lib/CodeGen/CodeGenFunction.h lib/CodeGen/CodeGenModule.cpp lib/CodeGen/CodeGenModule.h lib/CodeGen/ItaniumCXXABI.cpp test/CodeGenCXX/static-init.cpp
John McCall
rjmccall at apple.com
Fri Mar 30 00:09:50 PDT 2012
Author: rjmccall
Date: Fri Mar 30 02:09:50 2012
New Revision: 153733
URL: http://llvm.org/viewvc/llvm-project?rev=153733&view=rev
Log:
Do the static-locals thing properly in the face of unions and
other things which might mess with the variable's type.
Modified:
cfe/trunk/lib/CodeGen/CGCXXABI.cpp
cfe/trunk/lib/CodeGen/CGCXXABI.h
cfe/trunk/lib/CodeGen/CGDecl.cpp
cfe/trunk/lib/CodeGen/CGDeclCXX.cpp
cfe/trunk/lib/CodeGen/CodeGenFunction.h
cfe/trunk/lib/CodeGen/CodeGenModule.cpp
cfe/trunk/lib/CodeGen/CodeGenModule.h
cfe/trunk/lib/CodeGen/ItaniumCXXABI.cpp
cfe/trunk/test/CodeGenCXX/static-init.cpp
Modified: cfe/trunk/lib/CodeGen/CGCXXABI.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGCXXABI.cpp?rev=153733&r1=153732&r2=153733&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGCXXABI.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGCXXABI.cpp Fri Mar 30 02:09:50 2012
@@ -172,7 +172,7 @@
void CGCXXABI::EmitGuardedInit(CodeGenFunction &CGF,
const VarDecl &D,
- llvm::GlobalVariable *GV,
+ llvm::Constant *GV,
bool PerformInit) {
ErrorUnsupportedABI(CGF, "static local variable initialization");
}
Modified: cfe/trunk/lib/CodeGen/CGCXXABI.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGCXXABI.h?rev=153733&r1=153732&r2=153733&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGCXXABI.h (original)
+++ cfe/trunk/lib/CodeGen/CGCXXABI.h Fri Mar 30 02:09:50 2012
@@ -246,8 +246,9 @@
/// The variable may be:
/// - a static local variable
/// - a static data member of a class template instantiation
+ /// In either case, it will be a (possibly casted) llvm::GlobalVariable.
virtual void EmitGuardedInit(CodeGenFunction &CGF, const VarDecl &D,
- llvm::GlobalVariable *DeclPtr, bool PerformInit);
+ llvm::Constant *addr, bool PerformInit);
};
Modified: cfe/trunk/lib/CodeGen/CGDecl.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGDecl.cpp?rev=153733&r1=153732&r2=153733&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGDecl.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGDecl.cpp Fri Mar 30 02:09:50 2012
@@ -169,7 +169,24 @@
return ContextName + Separator + D.getNameAsString();
}
-llvm::GlobalVariable *
+/// We wanted to make a variable of one type, but the variable already
+/// exists with another. Is that type good enough?
+///
+/// The problem we're working around here is that giving a global
+/// variable an initializer can require changing its type in some
+/// convoluted circumstances.
+static bool isExistingVarAdequate(CodeGenModule &CGM,
+ llvm::Type *existing, llvm::Type *desired) {
+ // Equality makes for a good fast path.
+ if (existing == desired) return true;
+
+ // Otherwise, just require them to have the same size.
+ return (CGM.getTargetData().getTypeStoreSize(existing)
+ == CGM.getTargetData().getTypeStoreSize(desired));
+}
+
+
+llvm::Constant *
CodeGenFunction::CreateStaticVarDecl(const VarDecl &D,
const char *Separator,
llvm::GlobalValue::LinkageTypes Linkage) {
@@ -184,20 +201,27 @@
Name = GetStaticDeclName(*this, D, Separator);
llvm::Type *LTy = CGM.getTypes().ConvertTypeForMem(Ty);
+ unsigned addrspace = CGM.getContext().getTargetAddressSpace(Ty);
// In C++, there are strange possibilities here involving the
// double-emission of constructors and destructors.
if (CGM.getLangOpts().CPlusPlus) {
llvm::GlobalValue *value = CGM.getModule().getNamedValue(Name);
- if (value && isa<llvm::GlobalVariable>(value) &&
- value->getType() ==
- LTy->getPointerTo(CGM.getContext().getTargetAddressSpace(Ty)))
- return cast<llvm::GlobalVariable>(value);
+ if (value && isa<llvm::GlobalVariable>(value)) {
+ // Check that the type is compatible with the type we want. The
+ // simple equality check isn't good enough because initializers
+ // can force the changing of a type (e.g. with unions).
+ if (value->getType()->getAddressSpace() == addrspace &&
+ isExistingVarAdequate(CGM, value->getType()->getElementType(), LTy))
+ return llvm::ConstantExpr::getBitCast(value,
+ LTy->getPointerTo(addrspace));
+ }
if (value) {
CGM.Error(D.getLocation(),
- "problem emitting static variable: already present as "
- "different kind of symbol");
+ "problem emitting static variable '" + Name +
+ "': already present as different kind of symbol");
+
// Fall through and implicitly give it a uniqued name.
}
}
@@ -207,7 +231,7 @@
Ty.isConstant(getContext()), Linkage,
CGM.EmitNullConstant(D.getType()), Name, 0,
D.isThreadSpecified(),
- CGM.getContext().getTargetAddressSpace(Ty));
+ addrspace);
GV->setAlignment(getContext().getDeclAlign(&D).getQuantity());
if (Linkage != llvm::GlobalValue::InternalLinkage)
GV->setVisibility(CurFn->getVisibility());
@@ -222,80 +246,85 @@
return RD && !RD->hasTrivialDestructor();
}
-/// AddInitializerToStaticVarDecl - Add the initializer for 'D' to the
-/// global variable that has already been created for it. If the initializer
-/// has a different type than GV does, this may free GV and return a different
-/// one. Otherwise it just returns GV.
-llvm::GlobalVariable *
+/// AddInitializerToStaticVarDecl - Add the initializer for 'D' to
+/// the global variable that has already been created for it. If
+/// the initializer has a different type than GV does, this may
+/// force the underlying variable to change. Otherwise it just
+/// returns it.
+///
+/// The argument must be a (potentially casted) global variable,
+/// and the result will be one, too.
+llvm::Constant *
CodeGenFunction::AddInitializerToStaticVarDecl(const VarDecl &D,
- llvm::GlobalVariable *GV) {
- llvm::Constant *Init = CGM.EmitConstantInit(D, this);
+ llvm::Constant *addr) {
+ llvm::Constant *init = CGM.EmitConstantInit(D, this);
+
+ llvm::GlobalVariable *var =
+ cast<llvm::GlobalVariable>(addr->stripPointerCasts());
// If constant emission failed, then this should be a C++ static
// initializer.
- if (!Init) {
+ if (!init) {
if (!getContext().getLangOpts().CPlusPlus)
CGM.ErrorUnsupported(D.getInit(), "constant l-value expression");
else if (Builder.GetInsertBlock()) {
// Since we have a static initializer, this global variable can't
// be constant.
- GV->setConstant(false);
+ var->setConstant(false);
- EmitCXXGuardedInit(D, GV, /*PerformInit*/true);
+ EmitCXXGuardedInit(D, addr, /*PerformInit*/true);
}
- return GV;
+ return addr;
}
// The initializer may differ in type from the global. Rewrite
// the global to match the initializer. (We have to do this
// because some types, like unions, can't be completely represented
// in the LLVM type system.)
- if (GV->getType()->getElementType() != Init->getType()) {
- llvm::GlobalVariable *OldGV = GV;
-
- GV = new llvm::GlobalVariable(CGM.getModule(), Init->getType(),
- OldGV->isConstant(),
- OldGV->getLinkage(), Init, "",
- /*InsertBefore*/ OldGV,
- D.isThreadSpecified(),
- CGM.getContext().getTargetAddressSpace(D.getType()));
- GV->setVisibility(OldGV->getVisibility());
+ if (var->getType()->getElementType() != init->getType()) {
+ llvm::GlobalVariable *newVar
+ = new llvm::GlobalVariable(CGM.getModule(), init->getType(),
+ var->isConstant(),
+ var->getLinkage(), init, "",
+ /*InsertBefore*/ var,
+ D.isThreadSpecified(),
+ var->getType()->getAddressSpace());
+ newVar->setVisibility(var->getVisibility());
// Steal the name of the old global
- GV->takeName(OldGV);
+ newVar->takeName(var);
// Replace all uses of the old global with the new global
- llvm::Constant *NewPtrForOldDecl =
- llvm::ConstantExpr::getBitCast(GV, OldGV->getType());
- OldGV->replaceAllUsesWith(NewPtrForOldDecl);
+ addr = llvm::ConstantExpr::getBitCast(newVar, addr->getType());
+ var->replaceAllUsesWith(addr);
// Erase the old global, since it is no longer used.
- OldGV->eraseFromParent();
+ var->eraseFromParent();
+ var = newVar;
}
- GV->setConstant(CGM.isTypeConstant(D.getType(), true));
- GV->setInitializer(Init);
+ var->setConstant(CGM.isTypeConstant(D.getType(), true));
+ var->setInitializer(init);
if (hasNontrivialDestruction(D.getType())) {
// We have a constant initializer, but a nontrivial destructor. We still
// need to perform a guarded "initialization" in order to register the
// destructor.
- EmitCXXGuardedInit(D, GV, /*PerformInit*/false);
+ EmitCXXGuardedInit(D, addr, /*PerformInit*/false);
}
- return GV;
+ return addr;
}
void CodeGenFunction::EmitStaticVarDecl(const VarDecl &D,
llvm::GlobalValue::LinkageTypes Linkage) {
- llvm::Value *&DMEntry = LocalDeclMap[&D];
- assert(DMEntry == 0 && "Decl already exists in localdeclmap!");
- llvm::GlobalVariable *GV = CreateStaticVarDecl(D, ".", Linkage);
+ llvm::Constant *addr = CreateStaticVarDecl(D, ".", Linkage);
// Store into LocalDeclMap before generating initializer to handle
// circular references.
- DMEntry = GV;
+ assert(!LocalDeclMap.count(&D) && "Decl already exists in localdeclmap!");
+ LocalDeclMap[&D] = addr;
// We can't have a VLA here, but we can have a pointer to a VLA,
// even though that doesn't really make any sense.
@@ -305,40 +334,34 @@
// Local static block variables must be treated as globals as they may be
// referenced in their RHS initializer block-literal expresion.
- CGM.setStaticLocalDeclAddress(&D, GV);
+ CGM.setStaticLocalDeclAddress(&D, addr);
// If this value has an initializer, emit it.
+ // This can leave us with a casted pointer.
if (D.getInit())
- GV = AddInitializerToStaticVarDecl(D, GV);
+ addr = AddInitializerToStaticVarDecl(D, addr);
- GV->setAlignment(getContext().getDeclAlign(&D).getQuantity());
+ llvm::GlobalVariable *var =
+ cast<llvm::GlobalVariable>(addr->stripPointerCasts());
+ var->setAlignment(getContext().getDeclAlign(&D).getQuantity());
if (D.hasAttr<AnnotateAttr>())
- CGM.AddGlobalAnnotations(&D, GV);
+ CGM.AddGlobalAnnotations(&D, var);
if (const SectionAttr *SA = D.getAttr<SectionAttr>())
- GV->setSection(SA->getName());
+ var->setSection(SA->getName());
if (D.hasAttr<UsedAttr>())
- CGM.AddUsedGlobal(GV);
+ CGM.AddUsedGlobal(var);
- // We may have to cast the constant because of the initializer
- // mismatch above.
- //
- // FIXME: It is really dangerous to store this in the map; if anyone
- // RAUW's the GV uses of this constant will be invalid.
- llvm::Type *LTy = CGM.getTypes().ConvertTypeForMem(D.getType());
- llvm::Type *LPtrTy =
- LTy->getPointerTo(CGM.getContext().getTargetAddressSpace(D.getType()));
- llvm::Constant *CastedVal = llvm::ConstantExpr::getBitCast(GV, LPtrTy);
- DMEntry = CastedVal;
- CGM.setStaticLocalDeclAddress(&D, CastedVal);
+ LocalDeclMap[&D] = addr;
+ CGM.setStaticLocalDeclAddress(&D, addr);
// Emit global variable debug descriptor for static vars.
CGDebugInfo *DI = getDebugInfo();
if (DI) {
DI->setLocation(D.getLocation());
- DI->EmitGlobalVariable(static_cast<llvm::GlobalVariable *>(GV), &D);
+ DI->EmitGlobalVariable(var, &D);
}
}
Modified: cfe/trunk/lib/CodeGen/CGDeclCXX.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGDeclCXX.cpp?rev=153733&r1=153732&r2=153733&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGDeclCXX.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGDeclCXX.cpp Fri Mar 30 02:09:50 2012
@@ -179,7 +179,7 @@
}
void CodeGenFunction::EmitCXXGuardedInit(const VarDecl &D,
- llvm::GlobalVariable *DeclPtr,
+ llvm::Constant *addr,
bool PerformInit) {
// If we've been asked to forbid guard variables, emit an error now.
// This diagnostic is hard-coded for Darwin's use case; we can find
@@ -189,7 +189,7 @@
"this initialization requires a guard variable, which "
"the kernel does not support");
- CGM.getCXXABI().EmitGuardedInit(*this, D, DeclPtr, PerformInit);
+ CGM.getCXXABI().EmitGuardedInit(*this, D, addr, PerformInit);
}
static llvm::Function *
Modified: cfe/trunk/lib/CodeGen/CodeGenFunction.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CodeGenFunction.h?rev=153733&r1=153732&r2=153733&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CodeGenFunction.h (original)
+++ cfe/trunk/lib/CodeGen/CodeGenFunction.h Fri Mar 30 02:09:50 2012
@@ -2392,17 +2392,17 @@
/// CreateStaticVarDecl - Create a zero-initialized LLVM global for
/// a static local variable.
- llvm::GlobalVariable *CreateStaticVarDecl(const VarDecl &D,
- const char *Separator,
- llvm::GlobalValue::LinkageTypes Linkage);
-
- /// AddInitializerToStaticVarDecl - Add the initializer for 'D' to the
- /// global variable that has already been created for it. If the initializer
- /// has a different type than GV does, this may free GV and return a different
- /// one. Otherwise it just returns GV.
- llvm::GlobalVariable *
- AddInitializerToStaticVarDecl(const VarDecl &D,
- llvm::GlobalVariable *GV);
+ llvm::Constant *CreateStaticVarDecl(const VarDecl &D,
+ const char *Separator,
+ llvm::GlobalValue::LinkageTypes Linkage);
+
+ /// AddInitializerToStaticVarDecl - Add the initializer for 'D' to
+ /// the global variable that has already been created for it. If
+ /// the initializer has a different type than GV does, this may
+ /// force the underlying variable to change. Otherwise it just
+ /// returns it.
+ llvm::Constant *
+ AddInitializerToStaticVarDecl(const VarDecl &D, llvm::Constant *GV);
/// EmitCXXGlobalVarDeclInit - Create the initializer for a C++
@@ -2420,7 +2420,7 @@
/// possible to prove that an initialization will be done exactly
/// once, e.g. with a static local variable or a static data member
/// of a class template.
- void EmitCXXGuardedInit(const VarDecl &D, llvm::GlobalVariable *DeclPtr,
+ void EmitCXXGuardedInit(const VarDecl &D, llvm::Constant *addr,
bool PerformInit);
/// GenerateCXXGlobalInitFunc - Generates code for initializing global
Modified: cfe/trunk/lib/CodeGen/CodeGenModule.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CodeGenModule.cpp?rev=153733&r1=153732&r2=153733&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CodeGenModule.cpp (original)
+++ cfe/trunk/lib/CodeGen/CodeGenModule.cpp Fri Mar 30 02:09:50 2012
@@ -197,8 +197,9 @@
return getContext().getTargetInfo().getTriple().isOSDarwin();
}
-void CodeGenModule::Error(SourceLocation loc, StringRef error) {
- unsigned diagID = getDiags().getCustomDiagID(DiagnosticsEngine::Error, error);
+void CodeGenModule::Error(SourceLocation loc, const Twine &error) {
+ unsigned diagID = getDiags().getCustomDiagID(DiagnosticsEngine::Error,
+ error.str());
getDiags().Report(Context.getFullLoc(loc), diagID);
}
Modified: cfe/trunk/lib/CodeGen/CodeGenModule.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CodeGenModule.h?rev=153733&r1=153732&r2=153733&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CodeGenModule.h (original)
+++ cfe/trunk/lib/CodeGen/CodeGenModule.h Fri Mar 30 02:09:50 2012
@@ -733,7 +733,7 @@
llvm::Constant *EmitNullConstantForBase(const CXXRecordDecl *Record);
/// Error - Emit a general error that something can't be done.
- void Error(SourceLocation loc, StringRef error);
+ void Error(SourceLocation loc, const Twine &error);
/// ErrorUnsupported - Print out an error that codegen doesn't support the
/// specified stmt yet.
Modified: cfe/trunk/lib/CodeGen/ItaniumCXXABI.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/ItaniumCXXABI.cpp?rev=153733&r1=153732&r2=153733&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/ItaniumCXXABI.cpp (original)
+++ cfe/trunk/lib/CodeGen/ItaniumCXXABI.cpp Fri Mar 30 02:09:50 2012
@@ -123,7 +123,7 @@
llvm::Value *&AllocPtr, CharUnits &CookieSize);
void EmitGuardedInit(CodeGenFunction &CGF, const VarDecl &D,
- llvm::GlobalVariable *DeclPtr, bool PerformInit);
+ llvm::Constant *addr, bool PerformInit);
};
class ARMCXXABI : public ItaniumCXXABI {
@@ -1064,7 +1064,7 @@
/// just special-case it at particular places.
void ItaniumCXXABI::EmitGuardedInit(CodeGenFunction &CGF,
const VarDecl &D,
- llvm::GlobalVariable *GV,
+ llvm::Constant *varAddr,
bool PerformInit) {
CGBuilderTy &Builder = CGF.Builder;
@@ -1075,9 +1075,14 @@
llvm::IntegerType *guardTy;
+ // Find the underlying global variable for linkage purposes.
+ // This may not have the right type for actual evaluation purposes.
+ llvm::GlobalVariable *var =
+ cast<llvm::GlobalVariable>(varAddr->stripPointerCasts());
+
// If we have a global variable with internal linkage and thread-safe statics
// are disabled, we can just let the guard variable be of type i8.
- bool useInt8GuardVariable = !threadsafe && GV->hasInternalLinkage();
+ bool useInt8GuardVariable = !threadsafe && var->hasInternalLinkage();
if (useInt8GuardVariable) {
guardTy = CGF.Int8Ty;
} else {
@@ -1103,9 +1108,10 @@
existingGuard->getType() == guardPtrTy) {
guard = cast<llvm::GlobalVariable>(existingGuard); // okay
} else {
- CGM.Error(D.getLocation(),
- "problem emitting guard for static variable: "
- "already present as different kind of symbol");
+ CGM.Error(D.getLocation(), "problem emitting static variable '"
+ + guardName.str() +
+ "': already present as different kind of symbol");
+
// Fall through and implicitly give it a uniqued name.
}
}
@@ -1113,10 +1119,10 @@
if (!guard) {
// Just absorb linkage and visibility from the variable.
guard = new llvm::GlobalVariable(CGM.getModule(), guardTy,
- false, GV->getLinkage(),
+ false, var->getLinkage(),
llvm::ConstantInt::get(guardTy, 0),
guardName.str());
- guard->setVisibility(GV->getVisibility());
+ guard->setVisibility(var->getVisibility());
}
// Test whether the variable has completed initialization.
@@ -1196,7 +1202,7 @@
}
// Emit the initializer and add a global destructor if appropriate.
- CGF.EmitCXXGlobalVarDeclInit(D, GV, PerformInit);
+ CGF.EmitCXXGlobalVarDeclInit(D, varAddr, PerformInit);
if (threadsafe) {
// Pop the guard-abort cleanup if we pushed one.
Modified: cfe/trunk/test/CodeGenCXX/static-init.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCXX/static-init.cpp?rev=153733&r1=153732&r2=153733&view=diff
==============================================================================
--- cfe/trunk/test/CodeGenCXX/static-init.cpp (original)
+++ cfe/trunk/test/CodeGenCXX/static-init.cpp Fri Mar 30 02:09:50 2012
@@ -3,6 +3,7 @@
// CHECK: @_ZZ1hvE1i = internal global i32 0, align 4
// CHECK: @base_req = global [4 x i8] c"foo\00", align 1
+// CHECK: @_ZZN5test31BC1EvE1u = internal global { i8, [3 x i8] } { i8 97, [3 x i8] undef }, align 4
// CHECK: @_ZZN5test1L6getvarEiE3var = internal constant [4 x i32] [i32 1, i32 0, i32 2, i32 4], align 16
// CHECK: @_ZZ2h2vE1i = linkonce_odr global i32 0
// CHECK: @_ZGVZ2h2vE1i = linkonce_odr global i64 0
@@ -129,3 +130,23 @@
// CHECK: store i32 [[T0]], i32* @_ZZN5test21BD1EvE1y,
// CHECK: call void @__cxa_guard_release(i64* @_ZGVZN5test21BD1EvE1y)
}
+
+// This shouldn't error out.
+namespace test3 {
+ struct A {
+ A();
+ ~A();
+ };
+
+ struct B : virtual A {
+ B();
+ ~B();
+ };
+
+ B::B() {
+ union U { char x; int i; };
+ static U u = { 'a' };
+ }
+ // CHECK: define void @_ZN5test31BC1Ev(
+ // CHECK: define void @_ZN5test31BC2Ev(
+}
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