r296374 - [ubsan] Factor out logic to emit a range check. NFC.
Dmitry Vyukov via cfe-commits
cfe-commits at lists.llvm.org
Mon Feb 27 12:51:13 PST 2017
Does not seem to be related to tsan. It's just that somebody called a
directory with compiler tsan_release_build, but that seems to be the
only relation to tsan. Otherwise looks like a violated assertion in
clang.
On Mon, Feb 27, 2017 at 9:46 PM, Ivan Krasin <krasin at google.com> wrote:
> Hi Vedant,
>
> not on top of my head. Dmitriy, can you please take a look?
>
> krasin
>
> On Mon, Feb 27, 2017 at 12:43 PM, Vedant Kumar <vsk at apple.com> wrote:
>>
>> Hi Ivan,
>>
>> I saw a bot failure on your job after this commit:
>>
>>
>> http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-autoconf/builds/5467/steps/tsan%20analyze/logs/stdio
>>
>> http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-autoconf/builds/5467/steps/build%20release%20tsan%20with%20clang/logs/stdio
>>
>> However, I cannot reproduce it locally with a stage2 TSAN build.
>>
>> After staring at my diff I couldn't find anything that would explain the
>> failure. No other bots seem upset.
>>
>> Do you have any idea about what's going on? Let me know if you want me to
>> revert...
>>
>> vedant
>>
>> > On Feb 27, 2017, at 11:46 AM, Vedant Kumar via cfe-commits
>> > <cfe-commits at lists.llvm.org> wrote:
>> >
>> > Author: vedantk
>> > Date: Mon Feb 27 13:46:19 2017
>> > New Revision: 296374
>> >
>> > URL: http://llvm.org/viewvc/llvm-project?rev=296374&view=rev
>> > Log:
>> > [ubsan] Factor out logic to emit a range check. NFC.
>> >
>> > This is a readability improvement, but it will also help prep an
>> > upcoming patch to detect UB loads from bitfields.
>> >
>> > Modified:
>> > cfe/trunk/lib/CodeGen/CGExpr.cpp
>> > cfe/trunk/lib/CodeGen/CodeGenFunction.h
>> >
>> > Modified: cfe/trunk/lib/CodeGen/CGExpr.cpp
>> > URL:
>> > http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGExpr.cpp?rev=296374&r1=296373&r2=296374&view=diff
>> >
>> > ==============================================================================
>> > --- cfe/trunk/lib/CodeGen/CGExpr.cpp (original)
>> > +++ cfe/trunk/lib/CodeGen/CGExpr.cpp Mon Feb 27 13:46:19 2017
>> > @@ -1301,6 +1301,46 @@ llvm::MDNode *CodeGenFunction::getRangeF
>> > return MDHelper.createRange(Min, End);
>> > }
>> >
>> > +bool CodeGenFunction::EmitScalarRangeCheck(llvm::Value *Value, QualType
>> > Ty,
>> > + SourceLocation Loc) {
>> > + bool HasBoolCheck = SanOpts.has(SanitizerKind::Bool);
>> > + bool HasEnumCheck = SanOpts.has(SanitizerKind::Enum);
>> > + if (!HasBoolCheck && !HasEnumCheck)
>> > + return false;
>> > +
>> > + bool IsBool = hasBooleanRepresentation(Ty) ||
>> > + NSAPI(CGM.getContext()).isObjCBOOLType(Ty);
>> > + bool NeedsBoolCheck = HasBoolCheck && IsBool;
>> > + bool NeedsEnumCheck = HasEnumCheck && Ty->getAs<EnumType>();
>> > + if (!NeedsBoolCheck && !NeedsEnumCheck)
>> > + return false;
>> > +
>> > + llvm::APInt Min, End;
>> > + if (!getRangeForType(*this, Ty, Min, End, /*StrictEnums=*/true,
>> > IsBool))
>> > + return true;
>> > +
>> > + SanitizerScope SanScope(this);
>> > + llvm::Value *Check;
>> > + --End;
>> > + if (!Min) {
>> > + Check = Builder.CreateICmpULE(
>> > + Value, llvm::ConstantInt::get(getLLVMContext(), End));
>> > + } else {
>> > + llvm::Value *Upper = Builder.CreateICmpSLE(
>> > + Value, llvm::ConstantInt::get(getLLVMContext(), End));
>> > + llvm::Value *Lower = Builder.CreateICmpSGE(
>> > + Value, llvm::ConstantInt::get(getLLVMContext(), Min));
>> > + Check = Builder.CreateAnd(Upper, Lower);
>> > + }
>> > + llvm::Constant *StaticArgs[] = {EmitCheckSourceLocation(Loc),
>> > + EmitCheckTypeDescriptor(Ty)};
>> > + SanitizerMask Kind =
>> > + NeedsEnumCheck ? SanitizerKind::Enum : SanitizerKind::Bool;
>> > + EmitCheck(std::make_pair(Check, Kind),
>> > SanitizerHandler::LoadInvalidValue,
>> > + StaticArgs, EmitCheckValue(Value));
>> > + return true;
>> > +}
>> > +
>> > llvm::Value *CodeGenFunction::EmitLoadOfScalar(Address Addr, bool
>> > Volatile,
>> > QualType Ty,
>> > SourceLocation Loc,
>> > @@ -1353,35 +1393,9 @@ llvm::Value *CodeGenFunction::EmitLoadOf
>> > false /*ConvertTypeToTag*/);
>> > }
>> >
>> > - bool IsBool = hasBooleanRepresentation(Ty) ||
>> > - NSAPI(CGM.getContext()).isObjCBOOLType(Ty);
>> > - bool NeedsBoolCheck = SanOpts.has(SanitizerKind::Bool) && IsBool;
>> > - bool NeedsEnumCheck =
>> > - SanOpts.has(SanitizerKind::Enum) && Ty->getAs<EnumType>();
>> > - if (NeedsBoolCheck || NeedsEnumCheck) {
>> > - SanitizerScope SanScope(this);
>> > - llvm::APInt Min, End;
>> > - if (getRangeForType(*this, Ty, Min, End, /*StrictEnums=*/true,
>> > IsBool)) {
>> > - --End;
>> > - llvm::Value *Check;
>> > - if (!Min)
>> > - Check = Builder.CreateICmpULE(
>> > - Load, llvm::ConstantInt::get(getLLVMContext(), End));
>> > - else {
>> > - llvm::Value *Upper = Builder.CreateICmpSLE(
>> > - Load, llvm::ConstantInt::get(getLLVMContext(), End));
>> > - llvm::Value *Lower = Builder.CreateICmpSGE(
>> > - Load, llvm::ConstantInt::get(getLLVMContext(), Min));
>> > - Check = Builder.CreateAnd(Upper, Lower);
>> > - }
>> > - llvm::Constant *StaticArgs[] = {
>> > - EmitCheckSourceLocation(Loc),
>> > - EmitCheckTypeDescriptor(Ty)
>> > - };
>> > - SanitizerMask Kind = NeedsEnumCheck ? SanitizerKind::Enum :
>> > SanitizerKind::Bool;
>> > - EmitCheck(std::make_pair(Check, Kind),
>> > SanitizerHandler::LoadInvalidValue,
>> > - StaticArgs, EmitCheckValue(Load));
>> > - }
>> > + if (EmitScalarRangeCheck(Load, Ty, Loc)) {
>> > + // In order to prevent the optimizer from throwing away the check,
>> > don't
>> > + // attach range metadata to the load.
>> > } else if (CGM.getCodeGenOpts().OptimizationLevel > 0)
>> > if (llvm::MDNode *RangeInfo = getRangeForLoadFromType(Ty))
>> > Load->setMetadata(llvm::LLVMContext::MD_range, RangeInfo);
>> >
>> > Modified: cfe/trunk/lib/CodeGen/CodeGenFunction.h
>> > URL:
>> > http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CodeGenFunction.h?rev=296374&r1=296373&r2=296374&view=diff
>> >
>> > ==============================================================================
>> > --- cfe/trunk/lib/CodeGen/CodeGenFunction.h (original)
>> > +++ cfe/trunk/lib/CodeGen/CodeGenFunction.h Mon Feb 27 13:46:19 2017
>> > @@ -2866,6 +2866,13 @@ public:
>> > /// representation to its value representation.
>> > llvm::Value *EmitFromMemory(llvm::Value *Value, QualType Ty);
>> >
>> > + /// Check if the scalar \p Value is within the valid range for the
>> > given
>> > + /// type \p Ty.
>> > + ///
>> > + /// Returns true if a check is needed (even if the range is unknown).
>> > + bool EmitScalarRangeCheck(llvm::Value *Value, QualType Ty,
>> > + SourceLocation Loc);
>> > +
>> > /// EmitLoadOfScalar - Load a scalar value from an address, taking
>> > /// care to appropriately convert from the memory representation to
>> > /// the LLVM value representation.
>> >
>> >
>> > _______________________________________________
>> > cfe-commits mailing list
>> > cfe-commits at lists.llvm.org
>> > http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
>>
>
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