r332886 - Revert r332847; it caused us to miscompile certain forms of reference initialization.
Richard Smith via cfe-commits
cfe-commits at lists.llvm.org
Mon May 21 13:36:58 PDT 2018
Author: rsmith
Date: Mon May 21 13:36:58 2018
New Revision: 332886
URL: http://llvm.org/viewvc/llvm-project?rev=332886&view=rev
Log:
Revert r332847; it caused us to miscompile certain forms of reference initialization.
Added:
cfe/trunk/test/SemaCXX/large-array-init.cpp
- copied unchanged from r332846, cfe/trunk/test/SemaCXX/large-array-init.cpp
Modified:
cfe/trunk/include/clang/AST/Expr.h
cfe/trunk/lib/AST/ExprConstant.cpp
cfe/trunk/lib/CodeGen/CGExprConstant.cpp
cfe/trunk/test/CodeGen/const-init.c
cfe/trunk/test/CodeGen/designated-initializers.c
cfe/trunk/test/CodeGen/union-init2.c
cfe/trunk/test/CodeGenCXX/cxx11-initializer-aggregate.cpp
cfe/trunk/test/CodeGenCXX/cxx1z-initializer-aggregate.cpp
cfe/trunk/test/CodeGenCXX/reference-init.cpp
Modified: cfe/trunk/include/clang/AST/Expr.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/AST/Expr.h?rev=332886&r1=332885&r2=332886&view=diff
==============================================================================
--- cfe/trunk/include/clang/AST/Expr.h (original)
+++ cfe/trunk/include/clang/AST/Expr.h Mon May 21 13:36:58 2018
@@ -537,13 +537,6 @@ public:
bool isConstantInitializer(ASTContext &Ctx, bool ForRef,
const Expr **Culprit = nullptr) const;
- enum SideEffectsKind {
- SE_NoSideEffects, ///< Strictly evaluate the expression.
- SE_AllowUndefinedBehavior, ///< Allow UB that we can give a value, but not
- ///< arbitrary unmodeled side effects.
- SE_AllowSideEffects ///< Allow any unmodeled side effect.
- };
-
/// EvalStatus is a struct with detailed info about an evaluation in progress.
struct EvalStatus {
/// Whether the evaluated expression has side effects.
@@ -572,11 +565,6 @@ public:
bool hasSideEffects() const {
return HasSideEffects;
}
-
- bool hasUnacceptableSideEffect(SideEffectsKind SEK) {
- return (SEK < SE_AllowSideEffects && HasSideEffects) ||
- (SEK < SE_AllowUndefinedBehavior && HasUndefinedBehavior);
- }
};
/// EvalResult is a struct with detailed info about an evaluated expression.
@@ -603,6 +591,13 @@ public:
/// side-effects.
bool EvaluateAsBooleanCondition(bool &Result, const ASTContext &Ctx) const;
+ enum SideEffectsKind {
+ SE_NoSideEffects, ///< Strictly evaluate the expression.
+ SE_AllowUndefinedBehavior, ///< Allow UB that we can give a value, but not
+ ///< arbitrary unmodeled side effects.
+ SE_AllowSideEffects ///< Allow any unmodeled side effect.
+ };
+
/// EvaluateAsInt - Return true if this is a constant which we can fold and
/// convert to an integer, using any crazy technique that we want to.
bool EvaluateAsInt(llvm::APSInt &Result, const ASTContext &Ctx,
Modified: cfe/trunk/lib/AST/ExprConstant.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/AST/ExprConstant.cpp?rev=332886&r1=332885&r2=332886&view=diff
==============================================================================
--- cfe/trunk/lib/AST/ExprConstant.cpp (original)
+++ cfe/trunk/lib/AST/ExprConstant.cpp Mon May 21 13:36:58 2018
@@ -10312,6 +10312,12 @@ bool Expr::EvaluateAsBooleanCondition(bo
HandleConversionToBool(Scratch.Val, Result);
}
+static bool hasUnacceptableSideEffect(Expr::EvalStatus &Result,
+ Expr::SideEffectsKind SEK) {
+ return (SEK < Expr::SE_AllowSideEffects && Result.HasSideEffects) ||
+ (SEK < Expr::SE_AllowUndefinedBehavior && Result.HasUndefinedBehavior);
+}
+
bool Expr::EvaluateAsInt(APSInt &Result, const ASTContext &Ctx,
SideEffectsKind AllowSideEffects) const {
if (!getType()->isIntegralOrEnumerationType())
@@ -10319,7 +10325,7 @@ bool Expr::EvaluateAsInt(APSInt &Result,
EvalResult ExprResult;
if (!EvaluateAsRValue(ExprResult, Ctx) || !ExprResult.Val.isInt() ||
- ExprResult.hasUnacceptableSideEffect(AllowSideEffects))
+ hasUnacceptableSideEffect(ExprResult, AllowSideEffects))
return false;
Result = ExprResult.Val.getInt();
@@ -10333,7 +10339,7 @@ bool Expr::EvaluateAsFloat(APFloat &Resu
EvalResult ExprResult;
if (!EvaluateAsRValue(ExprResult, Ctx) || !ExprResult.Val.isFloat() ||
- ExprResult.hasUnacceptableSideEffect(AllowSideEffects))
+ hasUnacceptableSideEffect(ExprResult, AllowSideEffects))
return false;
Result = ExprResult.Val.getFloat();
@@ -10411,7 +10417,7 @@ bool Expr::EvaluateAsInitializer(APValue
bool Expr::isEvaluatable(const ASTContext &Ctx, SideEffectsKind SEK) const {
EvalResult Result;
return EvaluateAsRValue(Result, Ctx) &&
- !Result.hasUnacceptableSideEffect(SEK);
+ !hasUnacceptableSideEffect(Result, SEK);
}
APSInt Expr::EvaluateKnownConstInt(const ASTContext &Ctx,
Modified: cfe/trunk/lib/CodeGen/CGExprConstant.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGExprConstant.cpp?rev=332886&r1=332885&r2=332886&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGExprConstant.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGExprConstant.cpp Mon May 21 13:36:58 2018
@@ -1392,40 +1392,20 @@ static QualType getNonMemoryType(CodeGen
return type;
}
-/// Checks if the specified initializer is equivalent to zero initialization.
-static bool isZeroInitializer(ConstantEmitter &CE, const Expr *Init) {
- if (auto *E = dyn_cast_or_null<CXXConstructExpr>(Init)) {
- CXXConstructorDecl *CD = E->getConstructor();
- return CD->isDefaultConstructor() && CD->isTrivial();
- }
-
- if (auto *IL = dyn_cast_or_null<InitListExpr>(Init)) {
- for (auto I : IL->inits())
- if (!isZeroInitializer(CE, I))
- return false;
- if (const Expr *Filler = IL->getArrayFiller())
- return isZeroInitializer(CE, Filler);
- return true;
- }
-
- QualType InitTy = Init->getType();
- if (InitTy->isIntegralOrEnumerationType() || InitTy->isPointerType()) {
- Expr::EvalResult Result;
- if (Init->EvaluateAsRValue(Result, CE.CGM.getContext()) &&
- !Result.hasUnacceptableSideEffect(Expr::SE_NoSideEffects))
- return (Result.Val.isInt() && Result.Val.getInt().isNullValue()) ||
- (Result.Val.isLValue() && Result.Val.isNullPointer());
- }
-
- return false;
-}
-
llvm::Constant *ConstantEmitter::tryEmitPrivateForVarInit(const VarDecl &D) {
// Make a quick check if variable can be default NULL initialized
// and avoid going through rest of code which may do, for c++11,
// initialization of memory to all NULLs.
- if (!D.hasLocalStorage() && isZeroInitializer(*this, D.getInit()))
- return CGM.EmitNullConstant(D.getType());
+ if (!D.hasLocalStorage()) {
+ QualType Ty = CGM.getContext().getBaseElementType(D.getType());
+ if (Ty->isRecordType())
+ if (const CXXConstructExpr *E =
+ dyn_cast_or_null<CXXConstructExpr>(D.getInit())) {
+ const CXXConstructorDecl *CD = E->getConstructor();
+ if (CD->isTrivial() && CD->isDefaultConstructor())
+ return CGM.EmitNullConstant(D.getType());
+ }
+ }
QualType destType = D.getType();
Modified: cfe/trunk/test/CodeGen/const-init.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/const-init.c?rev=332886&r1=332885&r2=332886&view=diff
==============================================================================
--- cfe/trunk/test/CodeGen/const-init.c (original)
+++ cfe/trunk/test/CodeGen/const-init.c Mon May 21 13:36:58 2018
@@ -167,7 +167,7 @@ void g30() {
int : 1;
int x;
} a = {};
- // CHECK: @g30.a = internal global %struct.anon.1 zeroinitializer, align 1
+ // CHECK: @g30.a = internal global %struct.anon.1 <{ i8 undef, i32 0 }>, align 1
#pragma pack()
}
Modified: cfe/trunk/test/CodeGen/designated-initializers.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/designated-initializers.c?rev=332886&r1=332885&r2=332886&view=diff
==============================================================================
--- cfe/trunk/test/CodeGen/designated-initializers.c (original)
+++ cfe/trunk/test/CodeGen/designated-initializers.c Mon May 21 13:36:58 2018
@@ -8,7 +8,7 @@ struct foo {
// CHECK: @u = global %union.anon zeroinitializer
union { int i; float f; } u = { };
-// CHECK: @u2 = global %union.anon.0 zeroinitializer
+// CHECK: @u2 = global { i32, [4 x i8] } { i32 0, [4 x i8] undef }
union { int i; double f; } u2 = { };
// CHECK: @u3 = global %union.anon.1 zeroinitializer
Modified: cfe/trunk/test/CodeGen/union-init2.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/union-init2.c?rev=332886&r1=332885&r2=332886&view=diff
==============================================================================
--- cfe/trunk/test/CodeGen/union-init2.c (original)
+++ cfe/trunk/test/CodeGen/union-init2.c Mon May 21 13:36:58 2018
@@ -5,7 +5,7 @@
union x {long long b;union x* a;} r = {.a = &r};
-// CHECK: global %union.z zeroinitializer
+// CHECK: global { [3 x i8], [5 x i8] } { [3 x i8] zeroinitializer, [5 x i8] undef }
union z {
char a[3];
long long b;
Modified: cfe/trunk/test/CodeGenCXX/cxx11-initializer-aggregate.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCXX/cxx11-initializer-aggregate.cpp?rev=332886&r1=332885&r2=332886&view=diff
==============================================================================
--- cfe/trunk/test/CodeGenCXX/cxx11-initializer-aggregate.cpp (original)
+++ cfe/trunk/test/CodeGenCXX/cxx11-initializer-aggregate.cpp Mon May 21 13:36:58 2018
@@ -51,30 +51,3 @@ namespace NonTrivialInit {
// meaningful.
B b[30] = {};
}
-
-namespace ZeroInit {
- enum { Zero, One };
- constexpr int zero() { return 0; }
- constexpr int *null() { return nullptr; }
- struct Filler {
- int x;
- Filler();
- };
- struct S1 {
- int x;
- };
-
- // These declarations, if implemented elementwise, require huge
- // amout of memory and compiler time.
- unsigned char data_1[1024 * 1024 * 1024 * 2u] = { 0 };
- unsigned char data_2[1024 * 1024 * 1024 * 2u] = { Zero };
- unsigned char data_3[1024][1024][1024] = {{{0}}};
- unsigned char data_4[1024 * 1024 * 1024 * 2u] = { zero() };
- int *data_5[1024 * 1024 * 512] = { nullptr };
- int *data_6[1024 * 1024 * 512] = { null() };
- struct S1 data_7[1024 * 1024 * 512] = {{0}};
-
- // This variable must be initialized elementwise.
- Filler data_e1[1024] = {};
- // CHECK: getelementptr inbounds {{.*}} @_ZN8ZeroInit7data_e1E
-}
Modified: cfe/trunk/test/CodeGenCXX/cxx1z-initializer-aggregate.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCXX/cxx1z-initializer-aggregate.cpp?rev=332886&r1=332885&r2=332886&view=diff
==============================================================================
--- cfe/trunk/test/CodeGenCXX/cxx1z-initializer-aggregate.cpp (original)
+++ cfe/trunk/test/CodeGenCXX/cxx1z-initializer-aggregate.cpp Mon May 21 13:36:58 2018
@@ -17,14 +17,14 @@ namespace Constant {
C c1 = {};
C c2 = {1};
- // CHECK: @_ZN8Constant2c1E = global %"struct.Constant::C" zeroinitializer, align 1
+ // CHECK: @_ZN8Constant2c1E = global { i8 } zeroinitializer, align 1
// CHECK: @_ZN8Constant2c2E = global { i8 } { i8 1 }, align 1
// Test packing bases into tail padding.
D d1 = {};
D d2 = {1, 2, 3};
D d3 = {1};
- // CHECK: @_ZN8Constant2d1E = global %"struct.Constant::D" zeroinitializer, align 4
+ // CHECK: @_ZN8Constant2d1E = global { i32, i8, i8 } zeroinitializer, align 4
// CHECK: @_ZN8Constant2d2E = global { i32, i8, i8 } { i32 1, i8 2, i8 3 }, align 4
// CHECK: @_ZN8Constant2d3E = global { i32, i8, i8 } { i32 1, i8 0, i8 0 }, align 4
Modified: cfe/trunk/test/CodeGenCXX/reference-init.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCXX/reference-init.cpp?rev=332886&r1=332885&r2=332886&view=diff
==============================================================================
--- cfe/trunk/test/CodeGenCXX/reference-init.cpp (original)
+++ cfe/trunk/test/CodeGenCXX/reference-init.cpp Mon May 21 13:36:58 2018
@@ -3,6 +3,12 @@
// RUN: %clang_cc1 -triple %itanium_abi_triple -emit-llvm %s -o - -std=c++11 | FileCheck %s --check-prefix=CHECK-CXX11
// expected-no-diagnostics
+#if __cplusplus >= 201103L
+// CHECK-CXX11: @_ZZ15InitRefWithListvE1r = internal constant i32* @_ZGRZ15InitRefWithListvE1r_
+// CHECK-CXX11: @_ZGRZ15InitRefWithListvE1r_ = internal constant i32 123
+int InitRefWithList() { static const int &r = {123}; return r; }
+#endif
+
struct XPTParamDescriptor {};
struct nsXPTParamInfo {
nsXPTParamInfo(const XPTParamDescriptor& desc);
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