[clang][AArch64] Move initialization of ptrauth-* function attrs #140277
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Move the initialization of ptrauth-* function attributes near the initialization of branch protection attributes. The semantics of these groups of attributes partially overlaps, so initialize them both in getTrivialDefaultFunctionAttributes() function to prevent getting them out of sync. This fixes C++ TLS wrappers.
atrosinenko
requested review from
asl,
ahmedbougacha,
DanielKristofKiss and
kovdan01
DanielKristofKiss
approved these changes
May 16, 2025
ojhunt
approved these changes
May 16, 2025
|
It seems that when I rebased this PR from an older version of call void %0() #1 [ "ptrauth"(i32 0, i64 0) ]
; ^^
@DanielKristofKiss As far as I know, at least one example of synthetic functions not protected with pac-ret is Function Multi Versioning resolvers. This could be fixed via a separate PR, though. |
|
Fixed the tests in 85c21ec:
@ojhunt I'm not working on it, thank you! |
llvmbot
added
clang
|
@llvm/pr-subscribers-backend-aarch64 @llvm/pr-subscribers-clang Author: Anatoly Trosinenko (atrosinenko) ChangesMove the initialization of ptrauth-* function attributes near the initialization of branch protection attributes. The semantics of these groups of attributes partially overlaps, so initialize them both in getTrivialDefaultFunctionAttributes() function to prevent getting them out of sync. This fixes C++ TLS wrappers. Full diff: https://github.com/llvm/llvm-project/pull/140277.diff 6 Files Affected:
diff --git a/clang/lib/CodeGen/CGCall.cpp b/clang/lib/CodeGen/CGCall.cpp
index bcd579454413e..bd920a2e3f2dd 100644
--- a/clang/lib/CodeGen/CGCall.cpp
+++ b/clang/lib/CodeGen/CGCall.cpp
@@ -2216,6 +2216,11 @@ void CodeGenModule::getDefaultFunctionAttributes(StringRef Name,
llvm::AttrBuilder &FuncAttrs) {
getTrivialDefaultFunctionAttributes(Name, HasOptnone, AttrOnCallSite,
FuncAttrs);
+
+ if (!AttrOnCallSite)
+ TargetCodeGenInfo::initPointerAuthFnAttributes(CodeGenOpts.PointerAuth,
+ FuncAttrs);
+
// If we're just getting the default, get the default values for mergeable
// attributes.
if (!AttrOnCallSite)
diff --git a/clang/lib/CodeGen/CodeGenFunction.cpp b/clang/lib/CodeGen/CodeGenFunction.cpp
index ac40aab97820d..4e79cdf0ef089 100644
--- a/clang/lib/CodeGen/CodeGenFunction.cpp
+++ b/clang/lib/CodeGen/CodeGenFunction.cpp
@@ -890,19 +890,6 @@ void CodeGenFunction::StartFunction(GlobalDecl GD, QualType RetTy,
FD->getBody()->getStmtClass() == Stmt::CoroutineBodyStmtClass)
SanOpts.Mask &= ~SanitizerKind::Null;
- // Add pointer authentication attributes.
- const CodeGenOptions &CodeGenOpts = CGM.getCodeGenOpts();
- if (CodeGenOpts.PointerAuth.ReturnAddresses)
- Fn->addFnAttr("ptrauth-returns");
- if (CodeGenOpts.PointerAuth.FunctionPointers)
- Fn->addFnAttr("ptrauth-calls");
- if (CodeGenOpts.PointerAuth.AuthTraps)
- Fn->addFnAttr("ptrauth-auth-traps");
- if (CodeGenOpts.PointerAuth.IndirectGotos)
- Fn->addFnAttr("ptrauth-indirect-gotos");
- if (CodeGenOpts.PointerAuth.AArch64JumpTableHardening)
- Fn->addFnAttr("aarch64-jump-table-hardening");
-
// Apply xray attributes to the function (as a string, for now)
bool AlwaysXRayAttr = false;
if (const auto *XRayAttr = D ? D->getAttr<XRayInstrumentAttr>() : nullptr) {
diff --git a/clang/lib/CodeGen/TargetInfo.cpp b/clang/lib/CodeGen/TargetInfo.cpp
index 75a7d3c7c73f0..7d176e421ac4e 100644
--- a/clang/lib/CodeGen/TargetInfo.cpp
+++ b/clang/lib/CodeGen/TargetInfo.cpp
@@ -258,6 +258,35 @@ void TargetCodeGenInfo::initBranchProtectionFnAttributes(
FuncAttrs.addAttribute("guarded-control-stack");
}
+void TargetCodeGenInfo::setPointerAuthFnAttributes(
+ const PointerAuthOptions &Opts, llvm::Function &F) {
+ auto UpdateAttr = [&F](bool AttrShouldExist, StringRef AttrName) {
+ if (AttrShouldExist && !F.hasFnAttribute(AttrName))
+ F.addFnAttr(AttrName);
+ if (!AttrShouldExist && F.hasFnAttribute(AttrName))
+ F.removeFnAttr(AttrName);
+ };
+ UpdateAttr(Opts.ReturnAddresses, "ptrauth-returns");
+ UpdateAttr((bool)Opts.FunctionPointers, "ptrauth-calls");
+ UpdateAttr(Opts.AuthTraps, "ptrauth-auth-traps");
+ UpdateAttr(Opts.IndirectGotos, "ptrauth-indirect-gotos");
+ UpdateAttr(Opts.AArch64JumpTableHardening, "aarch64-jump-table-hardening");
+}
+
+void TargetCodeGenInfo::initPointerAuthFnAttributes(
+ const PointerAuthOptions &Opts, llvm::AttrBuilder &FuncAttrs) {
+ if (Opts.ReturnAddresses)
+ FuncAttrs.addAttribute("ptrauth-returns");
+ if (Opts.FunctionPointers)
+ FuncAttrs.addAttribute("ptrauth-calls");
+ if (Opts.AuthTraps)
+ FuncAttrs.addAttribute("ptrauth-auth-traps");
+ if (Opts.IndirectGotos)
+ FuncAttrs.addAttribute("ptrauth-indirect-gotos");
+ if (Opts.AArch64JumpTableHardening)
+ FuncAttrs.addAttribute("aarch64-jump-table-hardening");
+}
+
namespace {
class DefaultTargetCodeGenInfo : public TargetCodeGenInfo {
public:
diff --git a/clang/lib/CodeGen/TargetInfo.h b/clang/lib/CodeGen/TargetInfo.h
index dd5dc0c32bd71..e94e2e1aac7ea 100644
--- a/clang/lib/CodeGen/TargetInfo.h
+++ b/clang/lib/CodeGen/TargetInfo.h
@@ -455,6 +455,15 @@ class TargetCodeGenInfo {
initBranchProtectionFnAttributes(const TargetInfo::BranchProtectionInfo &BPI,
llvm::AttrBuilder &FuncAttrs);
+ // Set the ptrauth-* attributes of the Function accordingly to the Opts.
+ // Remove attributes that contradict with current Opts.
+ static void setPointerAuthFnAttributes(const PointerAuthOptions &Opts,
+ llvm::Function &F);
+
+ // Add the ptrauth-* Attributes to the FuncAttrs.
+ static void initPointerAuthFnAttributes(const PointerAuthOptions &Opts,
+ llvm::AttrBuilder &FuncAttrs);
+
protected:
static std::string qualifyWindowsLibrary(StringRef Lib);
diff --git a/clang/lib/CodeGen/Targets/AArch64.cpp b/clang/lib/CodeGen/Targets/AArch64.cpp
index f098f09ebf581..6311d921f3fd6 100644
--- a/clang/lib/CodeGen/Targets/AArch64.cpp
+++ b/clang/lib/CodeGen/Targets/AArch64.cpp
@@ -155,6 +155,7 @@ class AArch64TargetCodeGenInfo : public TargetCodeGenInfo {
}
}
setBranchProtectionFnAttributes(BPI, *Fn);
+ setPointerAuthFnAttributes(CGM.getCodeGenOpts().PointerAuth, *Fn);
}
bool isScalarizableAsmOperand(CodeGen::CodeGenFunction &CGF,
diff --git a/clang/test/CodeGenCXX/arm64-generated-fn-attr.cpp b/clang/test/CodeGenCXX/arm64-generated-fn-attr.cpp
index 18d9da40d469b..630b5edbbc1d7 100644
--- a/clang/test/CodeGenCXX/arm64-generated-fn-attr.cpp
+++ b/clang/test/CodeGenCXX/arm64-generated-fn-attr.cpp
@@ -1,4 +1,9 @@
-// RUN: %clang_cc1 -triple aarch64 -mbranch-target-enforce -msign-return-address=all -fcxx-exceptions -fexceptions -emit-llvm %s -o - | FileCheck %s
+// RUN: %clang_cc1 -triple aarch64 -mbranch-target-enforce -msign-return-address=all \
+// RUN: -fcxx-exceptions -fexceptions -emit-llvm %s -o - \
+// RUN: | FileCheck --check-prefixes=CHECK,BTE-SIGNRA %s
+// RUN: %clang_cc1 -triple aarch64 -fptrauth-calls -fptrauth-returns -fptrauth-auth-traps -fptrauth-indirect-gotos \
+// RUN: -fcxx-exceptions -fexceptions -emit-llvm %s -o - \
+// RUN: | FileCheck --check-prefixes=CHECK,PAUTHTEST %s
// Check that functions generated by clang have the correct attributes
@@ -26,5 +31,7 @@ int testfn() noexcept {
// CHECK: define {{.*}} @_ZTW4var2() [[ATTR1]]
// CHECK: define {{.*}} @__tls_init() [[ATTR1]]
-// CHECK: attributes [[ATTR1]] = { {{.*}}"branch-target-enforcement" {{.*}}"sign-return-address"="all" "sign-return-address-key"="a_key"
-// CHECK: attributes [[ATTR2]] = { {{.*}}"branch-target-enforcement" {{.*}}"sign-return-address"="all" "sign-return-address-key"="a_key"
+// BTE-SIGNRA: attributes [[ATTR1]] = { {{.*}}"branch-target-enforcement" {{.*}}"sign-return-address"="all" "sign-return-address-key"="a_key"
+// BTE-SIGNRA: attributes [[ATTR2]] = { {{.*}}"branch-target-enforcement" {{.*}}"sign-return-address"="all" "sign-return-address-key"="a_key"
+// PAUTHTEST: attributes [[ATTR1]] = { {{.*}}"ptrauth-auth-traps" "ptrauth-calls" "ptrauth-indirect-gotos" "ptrauth-returns"
+// PAUTHTEST: attributes [[ATTR2]] = { {{.*}}"ptrauth-auth-traps" "ptrauth-calls" "ptrauth-indirect-gotos" "ptrauth-returns"
|
DanielKristofKiss
approved these changes
May 18, 2025
|
LLVM Buildbot has detected a new failure on builder Full details are available at: https://lab.llvm.org/buildbot/#/builders/88/builds/11818 Here is the relevant piece of the build log for the reference |
sivan-shani
pushed a commit
to sivan-shani/llvm-project
that referenced
this pull request
Jun 3, 2025
…m#140277) Move the initialization of ptrauth-* function attributes near the initialization of branch protection attributes. The semantics of these groups of attributes partially overlaps, so handle both groups in getDefaultFunctionAttributes() and setTargetAttributes() functions to prevent getting them out of sync. This fixes C++ TLS wrappers.
ajaden-codes
pushed a commit
to Jaddyen/llvm-project
that referenced
this pull request
Jun 6, 2025
…m#140277) Move the initialization of ptrauth-* function attributes near the initialization of branch protection attributes. The semantics of these groups of attributes partially overlaps, so handle both groups in getDefaultFunctionAttributes() and setTargetAttributes() functions to prevent getting them out of sync. This fixes C++ TLS wrappers.
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Move the initialization of ptrauth-* function attributes near the initialization of branch protection attributes. The semantics of these groups of attributes partially overlaps, so handle both groups in getDefaultFunctionAttributes() and setTargetAttributes() functions to prevent getting them out of sync. This fixes C++ TLS wrappers.