Author: Timm Baeder Date: 2025-05-01T07:35:33+02:00 New Revision: c51be1be3ac9c66fc0c598298edd1fd224c1da07
URL: https://github.com/llvm/llvm-project/commit/c51be1be3ac9c66fc0c598298edd1fd224c1da07 DIFF: https://github.com/llvm/llvm-project/commit/c51be1be3ac9c66fc0c598298edd1fd224c1da07.diff LOG: [clang][bytecode] Fix checking for integer overflow (#137962) We need to evaluate both the True/False expressions of a conditional operator as well as the LHS/RHS of a binary operator in more cases. Added: Modified: clang/lib/AST/ByteCode/ByteCodeEmitter.h clang/lib/AST/ByteCode/Compiler.cpp clang/lib/AST/ByteCode/EvalEmitter.h clang/lib/AST/ByteCode/Interp.cpp clang/test/Sema/integer-overflow.c Removed: ################################################################################ diff --git a/clang/lib/AST/ByteCode/ByteCodeEmitter.h b/clang/lib/AST/ByteCode/ByteCodeEmitter.h index 5c7482923386e..9e9dd5e87cd7a 100644 --- a/clang/lib/AST/ByteCode/ByteCodeEmitter.h +++ b/clang/lib/AST/ByteCode/ByteCodeEmitter.h @@ -60,6 +60,7 @@ class ByteCodeEmitter { /// We're always emitting bytecode. bool isActive() const { return true; } + bool checkingForUndefinedBehavior() const { return false; } /// Callback for local registration. Local createLocal(Descriptor *D); diff --git a/clang/lib/AST/ByteCode/Compiler.cpp b/clang/lib/AST/ByteCode/Compiler.cpp index fe8d05c001a31..ae6574cf99159 100644 --- a/clang/lib/AST/ByteCode/Compiler.cpp +++ b/clang/lib/AST/ByteCode/Compiler.cpp @@ -866,12 +866,14 @@ bool Compiler<Emitter>::VisitBinaryOperator(const BinaryOperator *BO) { // Assignments require us to evalute the RHS first. if (BO->getOpcode() == BO_Assign) { - // We don't support assignments in C. - if (!Ctx.getLangOpts().CPlusPlus) - return this->emitInvalid(BO); if (!visit(RHS) || !visit(LHS)) return false; + + // We don't support assignments in C. + if (!Ctx.getLangOpts().CPlusPlus && !this->emitInvalid(BO)) + return false; + if (!this->emitFlip(*LT, *RT, BO)) return false; } else { @@ -2367,8 +2369,19 @@ bool Compiler<Emitter>::VisitAbstractConditionalOperator( return false; } - if (!this->visitBool(Condition)) + if (!this->visitBool(Condition)) { + // If the condition failed and we're checking for undefined behavior + // (which only happens with EvalEmitter) check the TrueExpr and FalseExpr + // as well. + if (this->checkingForUndefinedBehavior()) { + if (!this->discard(TrueExpr)) + return false; + if (!this->discard(FalseExpr)) + return false; + } return false; + } + if (!this->jumpFalse(LabelFalse)) return false; if (!visitChildExpr(TrueExpr)) diff --git a/clang/lib/AST/ByteCode/EvalEmitter.h b/clang/lib/AST/ByteCode/EvalEmitter.h index f53f86c31ec1e..18adf8656c0d5 100644 --- a/clang/lib/AST/ByteCode/EvalEmitter.h +++ b/clang/lib/AST/ByteCode/EvalEmitter.h @@ -69,6 +69,9 @@ class EvalEmitter : public SourceMapper { /// Since expressions can only jump forward, predicated execution is /// used to deal with if-else statements. bool isActive() const { return CurrentLabel == ActiveLabel; } + bool checkingForUndefinedBehavior() const { + return S.checkingForUndefinedBehavior(); + } /// Callback for registering a local. Local createLocal(Descriptor *D); diff --git a/clang/lib/AST/ByteCode/Interp.cpp b/clang/lib/AST/ByteCode/Interp.cpp index 62b449597bca8..1a7fc6cf2b2fd 100644 --- a/clang/lib/AST/ByteCode/Interp.cpp +++ b/clang/lib/AST/ByteCode/Interp.cpp @@ -1336,7 +1336,7 @@ static bool getField(InterpState &S, CodePtr OpPC, const Pointer &Ptr, return false; } - if (Off > Ptr.block()->getSize()) + if ((Ptr.getByteOffset() + Off) >= Ptr.block()->getSize()) return false; S.Stk.push<Pointer>(Ptr.atField(Off)); diff --git a/clang/test/Sema/integer-overflow.c b/clang/test/Sema/integer-overflow.c index 3141443c73305..30a47aa5f6ad6 100644 --- a/clang/test/Sema/integer-overflow.c +++ b/clang/test/Sema/integer-overflow.c @@ -1,4 +1,5 @@ // RUN: %clang_cc1 %s -verify -fsyntax-only -triple x86_64-pc-linux-gnu +// RUN: %clang_cc1 %s -verify -fsyntax-only -triple x86_64-pc-linux-gnu -fexperimental-new-constant-interpreter typedef unsigned long long uint64_t; typedef unsigned int uint32_t; _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
