r366123 - ARM MTE stack sanitizer.

[Evgeniy Stepanov via cfe-commits]

Author: eugenis
Date: Mon Jul 15 13:02:23 2019
New Revision: 366123

URL: http://llvm.org/viewvc/llvm-project?rev=366123&view=rev
Log:
ARM MTE stack sanitizer.

Add "memtag" sanitizer that detects and mitigates stack memory issues
using armv8.5 Memory Tagging Extension.

It is similar in principle to HWASan, which is a software implementation
of the same idea, but there are enough differencies to warrant a new
sanitizer type IMHO. It is also expected to have very different
performance properties.

The new sanitizer does not have a runtime library (it may grow one
later, along with a "debugging" mode). Similar to SafeStack and
StackProtector, the instrumentation pass (in a follow up change) will be
inserted in all cases, but will only affect functions marked with the
new sanitize_memtag attribute.

Reviewers: pcc, hctim, vitalybuka, ostannard

Subscribers: srhines, mehdi_amini, javed.absar, kristof.beyls, hiraditya, 
cryptoad, steven_wu, dexonsmith, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D64169

Added:
cfe/trunk/test/CodeGen/memtag-attr.cpp
cfe/trunk/test/Lexer/has_feature_memtag_sanitizer.cpp
Modified:
cfe/trunk/include/clang/Basic/Features.def
cfe/trunk/include/clang/Basic/Sanitizers.def
cfe/trunk/lib/CodeGen/CGDeclCXX.cpp
cfe/trunk/lib/CodeGen/CodeGenFunction.cpp
cfe/trunk/lib/CodeGen/CodeGenModule.cpp
cfe/trunk/lib/CodeGen/SanitizerMetadata.cpp
cfe/trunk/lib/Driver/SanitizerArgs.cpp
cfe/trunk/lib/Driver/ToolChains/Linux.cpp
cfe/trunk/test/Driver/fsanitize.c
cfe/trunk/test/SemaCXX/attr-no-sanitize.cpp

Modified: cfe/trunk/include/clang/Basic/Features.def
URL: 
http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/Features.def?rev=366123&r1=366122&r2=366123&view=diff
==
--- cfe/trunk/include/clang/Basic/Features.def (original)
+++ cfe/trunk/include/clang/Basic/Features.def Mon Jul 15 13:02:23 2019
@@ -42,6 +42,7 @@ FEATURE(address_sanitizer,
 FEATURE(hwaddress_sanitizer,
 LangOpts.Sanitize.hasOneOf(SanitizerKind::HWAddress |
SanitizerKind::KernelHWAddress))
+FEATURE(memtag_sanitizer, LangOpts.Sanitize.has(SanitizerKind::MemTag))
 FEATURE(xray_instrument, LangOpts.XRayInstrument)
 FEATURE(undefined_behavior_sanitizer,
 LangOpts.Sanitize.hasOneOf(SanitizerKind::Undefined))

Modified: cfe/trunk/include/clang/Basic/Sanitizers.def
URL: 
http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/Sanitizers.def?rev=366123&r1=366122&r2=366123&view=diff
==
--- cfe/trunk/include/clang/Basic/Sanitizers.def (original)
+++ cfe/trunk/include/clang/Basic/Sanitizers.def Mon Jul 15 13:02:23 2019
@@ -55,6 +55,9 @@ SANITIZER("hwaddress", HWAddress)
 // Kernel Hardware-assisted AddressSanitizer (KHWASan)
 SANITIZER("kernel-hwaddress", KernelHWAddress)
 
+// A variant of AddressSanitizer using AArch64 MTE extension.
+SANITIZER("memtag", MemTag)
+
 // MemorySanitizer
 SANITIZER("memory", Memory)
 

Modified: cfe/trunk/lib/CodeGen/CGDeclCXX.cpp
URL: 
http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGDeclCXX.cpp?rev=366123&r1=366122&r2=366123&view=diff
==
--- cfe/trunk/lib/CodeGen/CGDeclCXX.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGDeclCXX.cpp Mon Jul 15 13:02:23 2019
@@ -369,6 +369,10 @@ llvm::Function *CodeGenModule::CreateGlo
   !isInSanitizerBlacklist(SanitizerKind::KernelHWAddress, Fn, Loc))
 Fn->addFnAttr(llvm::Attribute::SanitizeHWAddress);
 
+  if (getLangOpts().Sanitize.has(SanitizerKind::MemTag) &&
+  !isInSanitizerBlacklist(SanitizerKind::MemTag, Fn, Loc))
+Fn->addFnAttr(llvm::Attribute::SanitizeMemTag);
+
   if (getLangOpts().Sanitize.has(SanitizerKind::Thread) &&
   !isInSanitizerBlacklist(SanitizerKind::Thread, Fn, Loc))
 Fn->addFnAttr(llvm::Attribute::SanitizeThread);

Modified: cfe/trunk/lib/CodeGen/CodeGenFunction.cpp
URL: 
http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CodeGenFunction.cpp?rev=366123&r1=366122&r2=366123&view=diff
==
--- cfe/trunk/lib/CodeGen/CodeGenFunction.cpp (original)
+++ cfe/trunk/lib/CodeGen/CodeGenFunction.cpp Mon Jul 15 13:02:23 2019
@@ -696,6 +696,8 @@ void CodeGenFunction::StartFunction(Glob
 Fn->addFnAttr(llvm::Attribute::SanitizeAddress);
   if (SanOpts.hasOneOf(SanitizerKind::HWAddress | 
SanitizerKind::KernelHWAddress))
 Fn->addFnAttr(llvm::Attribute::SanitizeHWAddress);
+  if (SanOpts.has(SanitizerKind::MemTag))
+Fn->addFnAttr(llvm::Attribute::SanitizeMemTag);
   if (SanOpts.has(SanitizerKind::Thread))
 Fn->addFnAttr(llvm::Attribute::SanitizeThread);
   if (SanOpts.hasOneOf(SanitizerKind::Memory | SanitizerKind::KernelMemory))

Modified: cfe/trunk/l

Re: r366123 - ARM MTE stack sanitizer.

[Amara Emerson via cfe-commits]

Hi Evgeniy,

This commit looks like it broke the lldb bot: 
http://green.lab.llvm.org/green/job/lldb-cmake/31011/ 


Can you take a look?

Amara

> On Jul 15, 2019, at 1:02 PM, Evgeniy Stepanov via cfe-commits 
>  wrote:
> 
> Author: eugenis
> Date: Mon Jul 15 13:02:23 2019
> New Revision: 366123
> 
> URL: http://llvm.org/viewvc/llvm-project?rev=366123&view=rev
> Log:
> ARM MTE stack sanitizer.
> 
> Add "memtag" sanitizer that detects and mitigates stack memory issues
> using armv8.5 Memory Tagging Extension.
> 
> It is similar in principle to HWASan, which is a software implementation
> of the same idea, but there are enough differencies to warrant a new
> sanitizer type IMHO. It is also expected to have very different
> performance properties.
> 
> The new sanitizer does not have a runtime library (it may grow one
> later, along with a "debugging" mode). Similar to SafeStack and
> StackProtector, the instrumentation pass (in a follow up change) will be
> inserted in all cases, but will only affect functions marked with the
> new sanitize_memtag attribute.
> 
> Reviewers: pcc, hctim, vitalybuka, ostannard
> 
> Subscribers: srhines, mehdi_amini, javed.absar, kristof.beyls, hiraditya, 
> cryptoad, steven_wu, dexonsmith, cfe-commits, llvm-commits
> 
> Tags: #clang, #llvm
> 
> Differential Revision: https://reviews.llvm.org/D64169
> 
> Added:
>cfe/trunk/test/CodeGen/memtag-attr.cpp
>cfe/trunk/test/Lexer/has_feature_memtag_sanitizer.cpp
> Modified:
>cfe/trunk/include/clang/Basic/Features.def
>cfe/trunk/include/clang/Basic/Sanitizers.def
>cfe/trunk/lib/CodeGen/CGDeclCXX.cpp
>cfe/trunk/lib/CodeGen/CodeGenFunction.cpp
>cfe/trunk/lib/CodeGen/CodeGenModule.cpp
>cfe/trunk/lib/CodeGen/SanitizerMetadata.cpp
>cfe/trunk/lib/Driver/SanitizerArgs.cpp
>cfe/trunk/lib/Driver/ToolChains/Linux.cpp
>cfe/trunk/test/Driver/fsanitize.c
>cfe/trunk/test/SemaCXX/attr-no-sanitize.cpp
> 
> Modified: cfe/trunk/include/clang/Basic/Features.def
> URL: 
> http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/Features.def?rev=366123&r1=366122&r2=366123&view=diff
> ==
> --- cfe/trunk/include/clang/Basic/Features.def (original)
> +++ cfe/trunk/include/clang/Basic/Features.def Mon Jul 15 13:02:23 2019
> @@ -42,6 +42,7 @@ FEATURE(address_sanitizer,
> FEATURE(hwaddress_sanitizer,
> LangOpts.Sanitize.hasOneOf(SanitizerKind::HWAddress |
>SanitizerKind::KernelHWAddress))
> +FEATURE(memtag_sanitizer, LangOpts.Sanitize.has(SanitizerKind::MemTag))
> FEATURE(xray_instrument, LangOpts.XRayInstrument)
> FEATURE(undefined_behavior_sanitizer,
> LangOpts.Sanitize.hasOneOf(SanitizerKind::Undefined))
> 
> Modified: cfe/trunk/include/clang/Basic/Sanitizers.def
> URL: 
> http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/Sanitizers.def?rev=366123&r1=366122&r2=366123&view=diff
> ==
> --- cfe/trunk/include/clang/Basic/Sanitizers.def (original)
> +++ cfe/trunk/include/clang/Basic/Sanitizers.def Mon Jul 15 13:02:23 2019
> @@ -55,6 +55,9 @@ SANITIZER("hwaddress", HWAddress)
> // Kernel Hardware-assisted AddressSanitizer (KHWASan)
> SANITIZER("kernel-hwaddress", KernelHWAddress)
> 
> +// A variant of AddressSanitizer using AArch64 MTE extension.
> +SANITIZER("memtag", MemTag)
> +
> // MemorySanitizer
> SANITIZER("memory", Memory)
> 
> 
> Modified: cfe/trunk/lib/CodeGen/CGDeclCXX.cpp
> URL: 
> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGDeclCXX.cpp?rev=366123&r1=366122&r2=366123&view=diff
> ==
> --- cfe/trunk/lib/CodeGen/CGDeclCXX.cpp (original)
> +++ cfe/trunk/lib/CodeGen/CGDeclCXX.cpp Mon Jul 15 13:02:23 2019
> @@ -369,6 +369,10 @@ llvm::Function *CodeGenModule::CreateGlo
>   !isInSanitizerBlacklist(SanitizerKind::KernelHWAddress, Fn, Loc))
> Fn->addFnAttr(llvm::Attribute::SanitizeHWAddress);
> 
> +  if (getLangOpts().Sanitize.has(SanitizerKind::MemTag) &&
> +  !isInSanitizerBlacklist(SanitizerKind::MemTag, Fn, Loc))
> +Fn->addFnAttr(llvm::Attribute::SanitizeMemTag);
> +
>   if (getLangOpts().Sanitize.has(SanitizerKind::Thread) &&
>   !isInSanitizerBlacklist(SanitizerKind::Thread, Fn, Loc))
> Fn->addFnAttr(llvm::Attribute::SanitizeThread);
> 
> Modified: cfe/trunk/lib/CodeGen/CodeGenFunction.cpp
> URL: 
> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CodeGenFunction.cpp?rev=366123&r1=366122&r2=366123&view=diff
> ==
> --- cfe/trunk/lib/CodeGen/CodeGenFunction.cpp (original)
> +++ cfe/trunk/lib/CodeGen/CodeGenFunction.cpp Mon Jul 15 13:02:23 2019
> @@ -696,6 +696,8 @@ void CodeGenFunction::StartFunction(Glob
> Fn->addFnAttr(llvm::Attrib

Re: r366123 - ARM MTE stack sanitizer.

[Evgenii Stepanov via cfe-commits]

Hi,

thanks for letting me know! Is this reproducible on Linux? It is
possible to extract a reproducer from the bot?

On Mon, Jul 15, 2019 at 9:30 PM Amara Emerson  wrote:
>
> Hi Evgeniy,
>
> This commit looks like it broke the lldb bot: 
> http://green.lab.llvm.org/green/job/lldb-cmake/31011/
>
> Can you take a look?
>
> Amara
>
> On Jul 15, 2019, at 1:02 PM, Evgeniy Stepanov via cfe-commits 
>  wrote:
>
> Author: eugenis
> Date: Mon Jul 15 13:02:23 2019
> New Revision: 366123
>
> URL: http://llvm.org/viewvc/llvm-project?rev=366123&view=rev
> Log:
> ARM MTE stack sanitizer.
>
> Add "memtag" sanitizer that detects and mitigates stack memory issues
> using armv8.5 Memory Tagging Extension.
>
> It is similar in principle to HWASan, which is a software implementation
> of the same idea, but there are enough differencies to warrant a new
> sanitizer type IMHO. It is also expected to have very different
> performance properties.
>
> The new sanitizer does not have a runtime library (it may grow one
> later, along with a "debugging" mode). Similar to SafeStack and
> StackProtector, the instrumentation pass (in a follow up change) will be
> inserted in all cases, but will only affect functions marked with the
> new sanitize_memtag attribute.
>
> Reviewers: pcc, hctim, vitalybuka, ostannard
>
> Subscribers: srhines, mehdi_amini, javed.absar, kristof.beyls, hiraditya, 
> cryptoad, steven_wu, dexonsmith, cfe-commits, llvm-commits
>
> Tags: #clang, #llvm
>
> Differential Revision: https://reviews.llvm.org/D64169
>
> Added:
>cfe/trunk/test/CodeGen/memtag-attr.cpp
>cfe/trunk/test/Lexer/has_feature_memtag_sanitizer.cpp
> Modified:
>cfe/trunk/include/clang/Basic/Features.def
>cfe/trunk/include/clang/Basic/Sanitizers.def
>cfe/trunk/lib/CodeGen/CGDeclCXX.cpp
>cfe/trunk/lib/CodeGen/CodeGenFunction.cpp
>cfe/trunk/lib/CodeGen/CodeGenModule.cpp
>cfe/trunk/lib/CodeGen/SanitizerMetadata.cpp
>cfe/trunk/lib/Driver/SanitizerArgs.cpp
>cfe/trunk/lib/Driver/ToolChains/Linux.cpp
>cfe/trunk/test/Driver/fsanitize.c
>cfe/trunk/test/SemaCXX/attr-no-sanitize.cpp
>
> Modified: cfe/trunk/include/clang/Basic/Features.def
> URL: 
> http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/Features.def?rev=366123&r1=366122&r2=366123&view=diff
> ==
> --- cfe/trunk/include/clang/Basic/Features.def (original)
> +++ cfe/trunk/include/clang/Basic/Features.def Mon Jul 15 13:02:23 2019
> @@ -42,6 +42,7 @@ FEATURE(address_sanitizer,
> FEATURE(hwaddress_sanitizer,
> LangOpts.Sanitize.hasOneOf(SanitizerKind::HWAddress |
>SanitizerKind::KernelHWAddress))
> +FEATURE(memtag_sanitizer, LangOpts.Sanitize.has(SanitizerKind::MemTag))
> FEATURE(xray_instrument, LangOpts.XRayInstrument)
> FEATURE(undefined_behavior_sanitizer,
> LangOpts.Sanitize.hasOneOf(SanitizerKind::Undefined))
>
> Modified: cfe/trunk/include/clang/Basic/Sanitizers.def
> URL: 
> http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/Sanitizers.def?rev=366123&r1=366122&r2=366123&view=diff
> ==
> --- cfe/trunk/include/clang/Basic/Sanitizers.def (original)
> +++ cfe/trunk/include/clang/Basic/Sanitizers.def Mon Jul 15 13:02:23 2019
> @@ -55,6 +55,9 @@ SANITIZER("hwaddress", HWAddress)
> // Kernel Hardware-assisted AddressSanitizer (KHWASan)
> SANITIZER("kernel-hwaddress", KernelHWAddress)
>
> +// A variant of AddressSanitizer using AArch64 MTE extension.
> +SANITIZER("memtag", MemTag)
> +
> // MemorySanitizer
> SANITIZER("memory", Memory)
>
>
> Modified: cfe/trunk/lib/CodeGen/CGDeclCXX.cpp
> URL: 
> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGDeclCXX.cpp?rev=366123&r1=366122&r2=366123&view=diff
> ==
> --- cfe/trunk/lib/CodeGen/CGDeclCXX.cpp (original)
> +++ cfe/trunk/lib/CodeGen/CGDeclCXX.cpp Mon Jul 15 13:02:23 2019
> @@ -369,6 +369,10 @@ llvm::Function *CodeGenModule::CreateGlo
>   !isInSanitizerBlacklist(SanitizerKind::KernelHWAddress, Fn, Loc))
> Fn->addFnAttr(llvm::Attribute::SanitizeHWAddress);
>
> +  if (getLangOpts().Sanitize.has(SanitizerKind::MemTag) &&
> +  !isInSanitizerBlacklist(SanitizerKind::MemTag, Fn, Loc))
> +Fn->addFnAttr(llvm::Attribute::SanitizeMemTag);
> +
>   if (getLangOpts().Sanitize.has(SanitizerKind::Thread) &&
>   !isInSanitizerBlacklist(SanitizerKind::Thread, Fn, Loc))
> Fn->addFnAttr(llvm::Attribute::SanitizeThread);
>
> Modified: cfe/trunk/lib/CodeGen/CodeGenFunction.cpp
> URL: 
> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CodeGenFunction.cpp?rev=366123&r1=366122&r2=366123&view=diff
> ==
> --- cfe/trunk/lib/CodeGen/CodeGenFunction.cpp (original)
> +++ cfe/trunk/lib/CodeGen/CodeGenFunction.cpp Mon Ju

Re: r366123 - ARM MTE stack sanitizer.

[Evgenii Stepanov via cfe-commits]

I could not reproduce this on Linux nor on Mac.
I wonder if triggering a clean build would help? I don't see a way to
do that though.

On Tue, Jul 16, 2019 at 10:50 AM Evgenii Stepanov
 wrote:
>
> Hi,
>
> thanks for letting me know! Is this reproducible on Linux? It is
> possible to extract a reproducer from the bot?
>
> On Mon, Jul 15, 2019 at 9:30 PM Amara Emerson  wrote:
> >
> > Hi Evgeniy,
> >
> > This commit looks like it broke the lldb bot: 
> > http://green.lab.llvm.org/green/job/lldb-cmake/31011/
> >
> > Can you take a look?
> >
> > Amara
> >
> > On Jul 15, 2019, at 1:02 PM, Evgeniy Stepanov via cfe-commits 
> >  wrote:
> >
> > Author: eugenis
> > Date: Mon Jul 15 13:02:23 2019
> > New Revision: 366123
> >
> > URL: http://llvm.org/viewvc/llvm-project?rev=366123&view=rev
> > Log:
> > ARM MTE stack sanitizer.
> >
> > Add "memtag" sanitizer that detects and mitigates stack memory issues
> > using armv8.5 Memory Tagging Extension.
> >
> > It is similar in principle to HWASan, which is a software implementation
> > of the same idea, but there are enough differencies to warrant a new
> > sanitizer type IMHO. It is also expected to have very different
> > performance properties.
> >
> > The new sanitizer does not have a runtime library (it may grow one
> > later, along with a "debugging" mode). Similar to SafeStack and
> > StackProtector, the instrumentation pass (in a follow up change) will be
> > inserted in all cases, but will only affect functions marked with the
> > new sanitize_memtag attribute.
> >
> > Reviewers: pcc, hctim, vitalybuka, ostannard
> >
> > Subscribers: srhines, mehdi_amini, javed.absar, kristof.beyls, hiraditya, 
> > cryptoad, steven_wu, dexonsmith, cfe-commits, llvm-commits
> >
> > Tags: #clang, #llvm
> >
> > Differential Revision: https://reviews.llvm.org/D64169
> >
> > Added:
> >cfe/trunk/test/CodeGen/memtag-attr.cpp
> >cfe/trunk/test/Lexer/has_feature_memtag_sanitizer.cpp
> > Modified:
> >cfe/trunk/include/clang/Basic/Features.def
> >cfe/trunk/include/clang/Basic/Sanitizers.def
> >cfe/trunk/lib/CodeGen/CGDeclCXX.cpp
> >cfe/trunk/lib/CodeGen/CodeGenFunction.cpp
> >cfe/trunk/lib/CodeGen/CodeGenModule.cpp
> >cfe/trunk/lib/CodeGen/SanitizerMetadata.cpp
> >cfe/trunk/lib/Driver/SanitizerArgs.cpp
> >cfe/trunk/lib/Driver/ToolChains/Linux.cpp
> >cfe/trunk/test/Driver/fsanitize.c
> >cfe/trunk/test/SemaCXX/attr-no-sanitize.cpp
> >
> > Modified: cfe/trunk/include/clang/Basic/Features.def
> > URL: 
> > http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/Features.def?rev=366123&r1=366122&r2=366123&view=diff
> > ==
> > --- cfe/trunk/include/clang/Basic/Features.def (original)
> > +++ cfe/trunk/include/clang/Basic/Features.def Mon Jul 15 13:02:23 2019
> > @@ -42,6 +42,7 @@ FEATURE(address_sanitizer,
> > FEATURE(hwaddress_sanitizer,
> > LangOpts.Sanitize.hasOneOf(SanitizerKind::HWAddress |
> >SanitizerKind::KernelHWAddress))
> > +FEATURE(memtag_sanitizer, LangOpts.Sanitize.has(SanitizerKind::MemTag))
> > FEATURE(xray_instrument, LangOpts.XRayInstrument)
> > FEATURE(undefined_behavior_sanitizer,
> > LangOpts.Sanitize.hasOneOf(SanitizerKind::Undefined))
> >
> > Modified: cfe/trunk/include/clang/Basic/Sanitizers.def
> > URL: 
> > http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/Sanitizers.def?rev=366123&r1=366122&r2=366123&view=diff
> > ==
> > --- cfe/trunk/include/clang/Basic/Sanitizers.def (original)
> > +++ cfe/trunk/include/clang/Basic/Sanitizers.def Mon Jul 15 13:02:23 2019
> > @@ -55,6 +55,9 @@ SANITIZER("hwaddress", HWAddress)
> > // Kernel Hardware-assisted AddressSanitizer (KHWASan)
> > SANITIZER("kernel-hwaddress", KernelHWAddress)
> >
> > +// A variant of AddressSanitizer using AArch64 MTE extension.
> > +SANITIZER("memtag", MemTag)
> > +
> > // MemorySanitizer
> > SANITIZER("memory", Memory)
> >
> >
> > Modified: cfe/trunk/lib/CodeGen/CGDeclCXX.cpp
> > URL: 
> > http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGDeclCXX.cpp?rev=366123&r1=366122&r2=366123&view=diff
> > ==
> > --- cfe/trunk/lib/CodeGen/CGDeclCXX.cpp (original)
> > +++ cfe/trunk/lib/CodeGen/CGDeclCXX.cpp Mon Jul 15 13:02:23 2019
> > @@ -369,6 +369,10 @@ llvm::Function *CodeGenModule::CreateGlo
> >   !isInSanitizerBlacklist(SanitizerKind::KernelHWAddress, Fn, Loc))
> > Fn->addFnAttr(llvm::Attribute::SanitizeHWAddress);
> >
> > +  if (getLangOpts().Sanitize.has(SanitizerKind::MemTag) &&
> > +  !isInSanitizerBlacklist(SanitizerKind::MemTag, Fn, Loc))
> > +Fn->addFnAttr(llvm::Attribute::SanitizeMemTag);
> > +
> >   if (getLangOpts().Sanitize.has(SanitizerKind::Thread) &&
> >   !isInSanitizerBlacklist(SanitizerKind::Thread, Fn, Loc))
> > Fn->ad