[cfe-commits] r154191 - in /cfe/trunk: lib/CodeGen/CGDeclCXX.cpp test/CodeGenCXX/arm.cpp test/CodeGenCXX/global-dtor-no-atexit.cpp test/CodeGenCXX/global-init.cpp test/CodeGenCXX/static-init.cpp
John McCall
rjmccall at apple.com
Fri Apr 6 11:21:06 PDT 2012
Author: rjmccall
Date: Fri Apr 6 13:21:06 2012
New Revision: 154191
URL: http://llvm.org/viewvc/llvm-project?rev=154191&view=rev
Log:
Use atexit when __cxa_atexit isn't available instead of adding a
global destructor entry. For some reason this isn't enabled for
apple-kexts; it'd be good to have documentation for that.
Based on a patch by Nakamura Takumi!
Modified:
cfe/trunk/lib/CodeGen/CGDeclCXX.cpp
cfe/trunk/test/CodeGenCXX/arm.cpp
cfe/trunk/test/CodeGenCXX/global-dtor-no-atexit.cpp
cfe/trunk/test/CodeGenCXX/global-init.cpp
cfe/trunk/test/CodeGenCXX/static-init.cpp
Modified: cfe/trunk/lib/CodeGen/CGDeclCXX.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGDeclCXX.cpp?rev=154191&r1=154190&r2=154191&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGDeclCXX.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGDeclCXX.cpp Fri Apr 6 13:21:06 2012
@@ -145,37 +145,109 @@
EmitStoreOfScalar(RV.getScalarVal(), DeclPtr, false, Alignment, T);
}
-void
-CodeGenFunction::EmitCXXGlobalDtorRegistration(llvm::Constant *DtorFn,
- llvm::Constant *DeclPtr) {
- // Generate a global destructor entry if not using __cxa_atexit.
- if (!CGM.getCodeGenOpts().CXAAtExit) {
- CGM.AddCXXDtorEntry(DtorFn, DeclPtr);
+/// Register a global destructor using __cxa_atexit.
+static void emitGlobalDtorWithCXAAtExit(CodeGenFunction &CGF,
+ llvm::Constant *dtor,
+ llvm::Constant *addr) {
+ // We're assuming that the destructor function is something we can
+ // reasonably call with the default CC. Go ahead and cast it to the
+ // right prototype.
+ llvm::Type *dtorTy =
+ llvm::FunctionType::get(CGF.VoidTy, CGF.Int8PtrTy, false)->getPointerTo();
+
+ // extern "C" int __cxa_atexit(void (*f)(void *), void *p, void *d);
+ llvm::Type *paramTys[] = { dtorTy, CGF.Int8PtrTy, CGF.Int8PtrTy };
+ llvm::FunctionType *atexitTy =
+ llvm::FunctionType::get(CGF.IntTy, paramTys, false);
+
+ // Fetch the actual function.
+ llvm::Constant *atexit =
+ CGF.CGM.CreateRuntimeFunction(atexitTy, "__cxa_atexit");
+ if (llvm::Function *fn = dyn_cast<llvm::Function>(atexit))
+ fn->setDoesNotThrow();
+
+ // Create a variable that binds the atexit to this shared object.
+ llvm::Constant *handle =
+ CGF.CGM.CreateRuntimeVariable(CGF.Int8Ty, "__dso_handle");
+
+ llvm::Value *args[] = {
+ llvm::ConstantExpr::getBitCast(dtor, dtorTy),
+ llvm::ConstantExpr::getBitCast(addr, CGF.Int8PtrTy),
+ handle
+ };
+ CGF.Builder.CreateCall(atexit, args);
+}
+
+static llvm::Function *
+CreateGlobalInitOrDestructFunction(CodeGenModule &CGM,
+ llvm::FunctionType *ty,
+ const Twine &name);
+
+/// Create a stub function, suitable for being passed to atexit,
+/// which passes the given address to the given destructor function.
+static llvm::Constant *createAtExitStub(CodeGenModule &CGM,
+ llvm::Constant *dtor,
+ llvm::Constant *addr) {
+ // Get the destructor function type, void(*)(void).
+ llvm::FunctionType *ty = llvm::FunctionType::get(CGM.VoidTy, false);
+ llvm::Function *fn =
+ CreateGlobalInitOrDestructFunction(CGM, ty,
+ Twine("__dtor_", addr->getName()));
+
+ CodeGenFunction CGF(CGM);
+
+ CGF.StartFunction(GlobalDecl(), CGM.getContext().VoidTy, fn,
+ CGM.getTypes().arrangeNullaryFunction(),
+ FunctionArgList(), SourceLocation());
+
+ llvm::CallInst *call = CGF.Builder.CreateCall(dtor, addr);
+
+ // Make sure the call and the callee agree on calling convention.
+ if (llvm::Function *dtorFn =
+ dyn_cast<llvm::Function>(dtor->stripPointerCasts()))
+ call->setCallingConv(dtorFn->getCallingConv());
+
+ CGF.FinishFunction();
+
+ return fn;
+}
+
+/// Register a global destructor using atexit.
+static void emitGlobalDtorWithAtExit(CodeGenFunction &CGF,
+ llvm::Constant *dtor,
+ llvm::Constant *addr) {
+ // Create a function which calls the destructor.
+ llvm::Constant *dtorStub = createAtExitStub(CGF.CGM, dtor, addr);
+
+ // extern "C" int atexit(void (*f)(void));
+ llvm::FunctionType *atexitTy =
+ llvm::FunctionType::get(CGF.IntTy, dtorStub->getType(), false);
+
+ llvm::Constant *atexit =
+ CGF.CGM.CreateRuntimeFunction(atexitTy, "atexit");
+ if (llvm::Function *atexitFn = dyn_cast<llvm::Function>(atexit))
+ atexitFn->setDoesNotThrow();
+
+ CGF.Builder.CreateCall(atexit, dtorStub);
+}
+
+void CodeGenFunction::EmitCXXGlobalDtorRegistration(llvm::Constant *dtor,
+ llvm::Constant *addr) {
+ // Use __cxa_atexit if available.
+ if (CGM.getCodeGenOpts().CXAAtExit) {
+ emitGlobalDtorWithCXAAtExit(*this, dtor, addr);
return;
}
- // Get the destructor function type
- llvm::Type *DtorFnTy = llvm::FunctionType::get(VoidTy, Int8PtrTy, false);
- DtorFnTy = llvm::PointerType::getUnqual(DtorFnTy);
-
- llvm::Type *Params[] = { DtorFnTy, Int8PtrTy, Int8PtrTy };
-
- // Get the __cxa_atexit function type
- // extern "C" int __cxa_atexit ( void (*f)(void *), void *p, void *d );
- llvm::FunctionType *AtExitFnTy =
- llvm::FunctionType::get(ConvertType(getContext().IntTy), Params, false);
-
- llvm::Constant *AtExitFn = CGM.CreateRuntimeFunction(AtExitFnTy,
- "__cxa_atexit");
- if (llvm::Function *Fn = dyn_cast<llvm::Function>(AtExitFn))
- Fn->setDoesNotThrow();
+ // In Apple kexts, we want to add a global destructor entry.
+ // FIXME: shouldn't this be guarded by some variable?
+ if (CGM.getContext().getLangOpts().AppleKext) {
+ // Generate a global destructor entry.
+ CGM.AddCXXDtorEntry(dtor, addr);
+ }
- llvm::Constant *Handle = CGM.CreateRuntimeVariable(Int8PtrTy,
- "__dso_handle");
- llvm::Value *Args[3] = { llvm::ConstantExpr::getBitCast(DtorFn, DtorFnTy),
- llvm::ConstantExpr::getBitCast(DeclPtr, Int8PtrTy),
- llvm::ConstantExpr::getBitCast(Handle, Int8PtrTy) };
- Builder.CreateCall(AtExitFn, Args);
+ // Otherwise, we just use atexit.
+ emitGlobalDtorWithAtExit(*this, dtor, addr);
}
void CodeGenFunction::EmitCXXGuardedInit(const VarDecl &D,
Modified: cfe/trunk/test/CodeGenCXX/arm.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCXX/arm.cpp?rev=154191&r1=154190&r2=154191&view=diff
==============================================================================
--- cfe/trunk/test/CodeGenCXX/arm.cpp (original)
+++ cfe/trunk/test/CodeGenCXX/arm.cpp Fri Apr 6 13:21:06 2012
@@ -20,9 +20,17 @@
// The global dtor needs the right calling conv with -fno-use-cxa-atexit
// rdar://7817590
-// Checked at end of file.
bar baz;
+// PR9593
+// Make sure atexit(3) is used for global dtors.
+
+// CHECK: call [[BAR:%.*]]* @_ZN3barC1Ev(
+// CHECK-NEXT: call i32 @atexit(void ()* @__dtor_baz)
+
+// CHECK: define internal void @__dtor_baz()
+// CHECK: call [[BAR]]* @_ZN3barD1Ev([[BAR]]* @baz)
+
// Destructors and constructors must return this.
namespace test1 {
void foo();
@@ -357,5 +365,5 @@
// CHECK: call void @_ZN5test21CD0Ev(
// CHECK: ret void
-// CHECK: @_GLOBAL__D_a()
-// CHECK: call %class.bar* @_ZN3barD1Ev(%class.bar* @baz)
+// CH_ECK: @_GLOBAL__D_a()
+// CH_ECK: call %class.bar* @_ZN3barD1Ev(%class.bar* @baz)
Modified: cfe/trunk/test/CodeGenCXX/global-dtor-no-atexit.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCXX/global-dtor-no-atexit.cpp?rev=154191&r1=154190&r2=154191&view=diff
==============================================================================
--- cfe/trunk/test/CodeGenCXX/global-dtor-no-atexit.cpp (original)
+++ cfe/trunk/test/CodeGenCXX/global-dtor-no-atexit.cpp Fri Apr 6 13:21:06 2012
@@ -3,10 +3,15 @@
// PR7097
// RUN: %clang_cc1 -triple x86_64 %s -fno-use-cxa-atexit -mconstructor-aliases -emit-llvm -o - | FileCheck %s
-// CHECK: define internal void @_GLOBAL__D_a()
-// CHECK: call void @_ZN1AD1Ev(%class.A* @b)
-// CHECK: call void @_ZN1AD1Ev(%class.A* @a)
-// CHECK: }
+// CHECK: call void @_ZN1AC1Ev([[A:%.*]]* @a)
+// CHECK-NEXT: call i32 @atexit(void ()* @__dtor_a)
+// CHECK: define internal void @__dtor_a() nounwind
+// CHECK: call void @_ZN1AD1Ev([[A]]* @a)
+
+// CHECK: call void @_ZN1AC1Ev([[A]]* @b)
+// CHECK-NEXT: call i32 @atexit(void ()* @__dtor_b)
+// CHECK: define internal void @__dtor_b() nounwind
+// CHECK: call void @_ZN1AD1Ev([[A]]* @b)
class A {
public:
@@ -15,3 +20,25 @@
};
A a, b;
+
+// PR9593
+// CHECK: define void @_Z4funcv()
+// CHECK: call i32 @__cxa_guard_acquire(i64* @_ZGVZ4funcvE2a1)
+// CHECK: call void @_ZN1AC1Ev([[A]]* @_ZZ4funcvE2a1)
+// CHECK-NEXT: call i32 @atexit(void ()* @__dtor__ZZ4funcvE2a1)
+// CHECK-NEXT: call void @__cxa_guard_release(i64* @_ZGVZ4funcvE2a1)
+
+// CHECK: call i32 @__cxa_guard_acquire(i64* @_ZGVZ4funcvE2a2)
+// CHECK: call void @_ZN1AC1Ev([[A]]* @_ZZ4funcvE2a2)
+// CHECK-NEXT: call i32 @atexit(void ()* @__dtor__ZZ4funcvE2a2)
+// CHECK-NEXT: call void @__cxa_guard_release(i64* @_ZGVZ4funcvE2a2)
+
+// CHECK: define internal void @__dtor__ZZ4funcvE2a1() nounwind
+// CHECK: call void @_ZN1AD1Ev([[A]]* @_ZZ4funcvE2a1)
+
+// CHECK: define internal void @__dtor__ZZ4funcvE2a2() nounwind
+// CHECK: call void @_ZN1AD1Ev([[A]]* @_ZZ4funcvE2a2)
+
+void func() {
+ static A a1, a2;
+}
Modified: cfe/trunk/test/CodeGenCXX/global-init.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCXX/global-init.cpp?rev=154191&r1=154190&r2=154191&view=diff
==============================================================================
--- cfe/trunk/test/CodeGenCXX/global-init.cpp (original)
+++ cfe/trunk/test/CodeGenCXX/global-init.cpp Fri Apr 6 13:21:06 2012
@@ -12,7 +12,7 @@
struct D { ~D(); };
-// CHECK: @__dso_handle = external unnamed_addr global i8*
+// CHECK: @__dso_handle = external unnamed_addr global i8
// CHECK: @c = global %struct.C zeroinitializer, align 8
// It's okay if we ever implement the IR-generation optimization to remove this.
@@ -24,18 +24,18 @@
// CHECK: @_ZN6PR59741bE = global %"struct.PR5974::B"* bitcast (i8* getelementptr (i8* bitcast (%"struct.PR5974::C"* @_ZN6PR59741cE to i8*), i64 4) to %"struct.PR5974::B"*), align 8
// CHECK: call void @_ZN1AC1Ev(%struct.A* @a)
-// CHECK: call i32 @__cxa_atexit(void (i8*)* bitcast (void (%struct.A*)* @_ZN1AD1Ev to void (i8*)*), i8* getelementptr inbounds (%struct.A* @a, i32 0, i32 0), i8* bitcast (i8** @__dso_handle to i8*))
+// CHECK: call i32 @__cxa_atexit(void (i8*)* bitcast (void (%struct.A*)* @_ZN1AD1Ev to void (i8*)*), i8* getelementptr inbounds (%struct.A* @a, i32 0, i32 0), i8* @__dso_handle)
A a;
// CHECK: call void @_ZN1BC1Ev(%struct.B* @b)
-// CHECK: call i32 @__cxa_atexit(void (i8*)* bitcast (void (%struct.B*)* @_ZN1BD1Ev to void (i8*)*), i8* getelementptr inbounds (%struct.B* @b, i32 0, i32 0), i8* bitcast (i8** @__dso_handle to i8*))
+// CHECK: call i32 @__cxa_atexit(void (i8*)* bitcast (void (%struct.B*)* @_ZN1BD1Ev to void (i8*)*), i8* getelementptr inbounds (%struct.B* @b, i32 0, i32 0), i8* @__dso_handle)
B b;
// PR6205: this should not require a global initializer
// CHECK-NOT: call void @_ZN1CC1Ev(%struct.C* @c)
C c;
-// CHECK: call i32 @__cxa_atexit(void (i8*)* bitcast (void (%struct.D*)* @_ZN1DD1Ev to void (i8*)*), i8* getelementptr inbounds (%struct.D* @d, i32 0, i32 0), i8* bitcast (i8** @__dso_handle to i8*))
+// CHECK: call i32 @__cxa_atexit(void (i8*)* bitcast (void (%struct.D*)* @_ZN1DD1Ev to void (i8*)*), i8* getelementptr inbounds (%struct.D* @d, i32 0, i32 0), i8* @__dso_handle)
D d;
// <rdar://problem/7458115>
Modified: cfe/trunk/test/CodeGenCXX/static-init.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCXX/static-init.cpp?rev=154191&r1=154190&r2=154191&view=diff
==============================================================================
--- cfe/trunk/test/CodeGenCXX/static-init.cpp (original)
+++ cfe/trunk/test/CodeGenCXX/static-init.cpp Fri Apr 6 13:21:06 2012
@@ -17,7 +17,7 @@
// CHECK: load atomic i8* bitcast (i64* @_ZGVZ1fvE1a to i8*) acquire, align 1
// CHECK: call i32 @__cxa_guard_acquire
// CHECK: call void @_ZN1AC1Ev
- // CHECK: call i32 @__cxa_atexit(void (i8*)* bitcast (void (%struct.A*)* @_ZN1AD1Ev to void (i8*)*), i8* getelementptr inbounds (%struct.A* @_ZZ1fvE1a, i32 0, i32 0), i8* bitcast (i8** @__dso_handle to i8*))
+ // CHECK: call i32 @__cxa_atexit(void (i8*)* bitcast (void (%struct.A*)* @_ZN1AD1Ev to void (i8*)*), i8* getelementptr inbounds (%struct.A* @_ZZ1fvE1a, i32 0, i32 0), i8* @__dso_handle)
// CHECK: call void @__cxa_guard_release
static A a;
}
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