Author: Jack Styles Date: 2024-05-10T08:09:02+01:00 New Revision: 6aac30fa43f094ac25269bda163dc89a88cb8da7
URL: https://github.com/llvm/llvm-project/commit/6aac30fa43f094ac25269bda163dc89a88cb8da7 DIFF: https://github.com/llvm/llvm-project/commit/6aac30fa43f094ac25269bda163dc89a88cb8da7.diff LOG: Update FEAT_PAuth_LR behaviour for AArch64 (#90614) Currently, LLVM enables `-mbranch-protection=standard` as `bti+pac-ret`. To align LLVM with the behaviour in GNU, this has been updated to `bti+pac-ret+pc` when FEAT_PAuth_LR is enabled as an optional feature via the `-mcpu=` options. If this is not enabled, then this will revert to the existing behaviour. Added: Modified: clang/lib/Basic/Targets/AArch64.cpp clang/lib/Driver/ToolChains/Clang.cpp clang/test/Preprocessor/aarch64-target-features.c llvm/docs/ReleaseNotes.rst llvm/include/llvm/TargetParser/AArch64TargetParser.h llvm/include/llvm/TargetParser/ARMTargetParserCommon.h llvm/lib/TargetParser/AArch64TargetParser.cpp llvm/lib/TargetParser/ARMTargetParserCommon.cpp Removed: ################################################################################ diff --git a/clang/lib/Basic/Targets/AArch64.cpp b/clang/lib/Basic/Targets/AArch64.cpp index 4b1545339f694..5db1ce78c657f 100644 --- a/clang/lib/Basic/Targets/AArch64.cpp +++ b/clang/lib/Basic/Targets/AArch64.cpp @@ -225,7 +225,7 @@ bool AArch64TargetInfo::validateBranchProtection(StringRef Spec, StringRef, BranchProtectionInfo &BPI, StringRef &Err) const { llvm::ARM::ParsedBranchProtection PBP; - if (!llvm::ARM::parseBranchProtection(Spec, PBP, Err)) + if (!llvm::ARM::parseBranchProtection(Spec, PBP, Err, HasPAuthLR)) return false; BPI.SignReturnAddr = diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp index 449eb9b2a965a..f81c2024ae486 100644 --- a/clang/lib/Driver/ToolChains/Clang.cpp +++ b/clang/lib/Driver/ToolChains/Clang.cpp @@ -55,6 +55,7 @@ #include "llvm/Support/Path.h" #include "llvm/Support/Process.h" #include "llvm/Support/YAMLParser.h" +#include "llvm/TargetParser/AArch64TargetParser.h" #include "llvm/TargetParser/ARMTargetParserCommon.h" #include "llvm/TargetParser/Host.h" #include "llvm/TargetParser/LoongArchTargetParser.h" @@ -1511,7 +1512,24 @@ static void CollectARMPACBTIOptions(const ToolChain &TC, const ArgList &Args, } else { StringRef DiagMsg; llvm::ARM::ParsedBranchProtection PBP; - if (!llvm::ARM::parseBranchProtection(A->getValue(), PBP, DiagMsg)) + bool EnablePAuthLR = false; + + // To know if we need to enable PAuth-LR As part of the standard branch + // protection option, it needs to be determined if the feature has been + // activated in the `march` argument. This information is stored within the + // CmdArgs variable and can be found using a search. + if (isAArch64) { + auto isPAuthLR = [](const char *member) { + llvm::AArch64::ExtensionInfo pauthlr_extension = + llvm::AArch64::getExtensionByID(llvm::AArch64::AEK_PAUTHLR); + return (pauthlr_extension.Feature.compare(member) == 0); + }; + + if (std::any_of(CmdArgs.begin(), CmdArgs.end(), isPAuthLR)) + EnablePAuthLR = true; + } + if (!llvm::ARM::parseBranchProtection(A->getValue(), PBP, DiagMsg, + EnablePAuthLR)) D.Diag(diag::err_drv_unsupported_option_argument) << A->getSpelling() << DiagMsg; if (!isAArch64 && PBP.Key == "b_key") diff --git a/clang/test/Preprocessor/aarch64-target-features.c b/clang/test/Preprocessor/aarch64-target-features.c index 4d10eeafa8847..82304a15a04a3 100644 --- a/clang/test/Preprocessor/aarch64-target-features.c +++ b/clang/test/Preprocessor/aarch64-target-features.c @@ -616,6 +616,9 @@ // ================== Check Armv9.5-A Pointer Authentication Enhancements(PAuth_LR). // RUN: %clang -target arm64-none-linux-gnu -march=armv8-a -x c -E -dM %s -o - | FileCheck -check-prefix=CHECK-PAUTH-LR-OFF %s // RUN: %clang -target arm64-none-linux-gnu -march=armv9.5-a -x c -E -dM %s -o - | FileCheck -check-prefix=CHECK-PAUTH-LR-OFF %s +// RUN: %clang -target arm64-none-linux-gnu -march=armv9.5-a -mbranch-protection=standard -x c -E -dM %s -o - | FileCheck -check-prefixes=CHECK-PAUTH-LR-OFF,CHECK-BRANCH-PROTECTION-NO-PC %s +// RUN: %clang -target arm64-none-linux-gnu -march=armv9.5-a+pauth-lr -mbranch-protection=standard -x c -E -dM %s -o - | FileCheck -check-prefixes=CHECK-PAUTH-LR,CHECK-BRANCH-PROTECTION-PC %s +// RUN: %clang -target arm64-none-linux-gnu -march=armv9.5-a+nopauth-lr -mbranch-protection=standard -x c -E -dM %s -o - | FileCheck -check-prefixes=CHECK-PAUTH-LR-OFF,CHECK-BRANCH-PROTECTION-NO-PC %s // RUN: %clang -target arm64-none-linux-gnu -march=armv8-a+pauth -mbranch-protection=none -x c -E -dM %s -o - | FileCheck -check-prefix=CHECK-PAUTH-LR-OFF %s // RUN: %clang -target arm64-none-linux-gnu -march=armv8-a+pauth-lr -mbranch-protection=none -x c -E -dM %s -o - | FileCheck -check-prefix=CHECK-PAUTH-LR %s // RUN: %clang -target arm64-none-linux-gnu -march=armv8-a+pauth-lr -mbranch-protection=bti -x c -E -dM %s -o - | FileCheck -check-prefix=CHECK-PAUTH-LR %s @@ -636,6 +639,7 @@ // RUN: %clang -target arm64-none-linux-gnu -march=armv8-a+pauth-lr -mbranch-protection=pac-ret+pc+b-key -x c -E -dM %s -o - | FileCheck -check-prefixes=CHECK-PAUTH-LR,CHECK-BRANCH-PROTECTION-PC-BKEY %s // RUN: %clang -target arm64-none-linux-gnu -march=armv8-a+pauth-lr -mbranch-protection=pac-ret+pc+leaf -x c -E -dM %s -o - | FileCheck -check-prefixes=CHECK-PAUTH-LR,CHECK-BRANCH-PROTECTION-PC-LEAF %s // RUN: %clang -target arm64-none-linux-gnu -march=armv8-a+pauth-lr -mbranch-protection=pac-ret+pc+leaf+b-key -x c -E -dM %s -o - | FileCheck -check-prefixes=CHECK-PAUTH-LR,CHECK-BRANCH-PROTECTION-PC-LEAF-BKEY %s +// CHECK-BRANCH-PROTECTION-NO-PC: #define __ARM_FEATURE_PAC_DEFAULT 1 // CHECK-BRANCH-PROTECTION-PC: #define __ARM_FEATURE_PAC_DEFAULT 9 // CHECK-BRANCH-PROTECTION-PC-BKEY: #define __ARM_FEATURE_PAC_DEFAULT 10 // CHECK-BRANCH-PROTECTION-PC-LEAF: #define __ARM_FEATURE_PAC_DEFAULT 13 diff --git a/llvm/docs/ReleaseNotes.rst b/llvm/docs/ReleaseNotes.rst index 26f1d33f68009..f2577e1684f5f 100644 --- a/llvm/docs/ReleaseNotes.rst +++ b/llvm/docs/ReleaseNotes.rst @@ -76,6 +76,11 @@ Changes to the AArch64 Backend * Added support for Cortex-A78AE, Cortex-A520AE, Cortex-A720AE, Cortex-R82AE, Neoverse-N3, Neoverse-V3 and Neoverse-V3AE CPUs. +* ``-mbranch-protection=standard`` now enables FEAT_PAuth_LR by + default when the feature is enabled. The new behaviour results + in ``standard`` being equal to ``bti+pac-ret+pc`` when ``+pauth-lr`` + is passed as part of ``-mcpu=`` options. + Changes to the AMDGPU Backend ----------------------------- diff --git a/llvm/include/llvm/TargetParser/AArch64TargetParser.h b/llvm/include/llvm/TargetParser/AArch64TargetParser.h index 1124420daf8d8..20c3f95173c28 100644 --- a/llvm/include/llvm/TargetParser/AArch64TargetParser.h +++ b/llvm/include/llvm/TargetParser/AArch64TargetParser.h @@ -676,6 +676,8 @@ inline constexpr Alias CpuAliases[] = {{"cobalt-100", "neoverse-n2"}, inline constexpr Alias ExtAliases[] = {{"rdma", "rdm"}}; +const ExtensionInfo &getExtensionByID(ArchExtKind(ExtID)); + bool getExtensionFeatures( const AArch64::ExtensionBitset &Extensions, std::vector<StringRef> &Features); diff --git a/llvm/include/llvm/TargetParser/ARMTargetParserCommon.h b/llvm/include/llvm/TargetParser/ARMTargetParserCommon.h index 8ae553ca80ddc..f6115718e9f5f 100644 --- a/llvm/include/llvm/TargetParser/ARMTargetParserCommon.h +++ b/llvm/include/llvm/TargetParser/ARMTargetParserCommon.h @@ -46,7 +46,7 @@ struct ParsedBranchProtection { }; bool parseBranchProtection(StringRef Spec, ParsedBranchProtection &PBP, - StringRef &Err); + StringRef &Err, bool EnablePAuthLR = false); } // namespace ARM } // namespace llvm diff --git a/llvm/lib/TargetParser/AArch64TargetParser.cpp b/llvm/lib/TargetParser/AArch64TargetParser.cpp index 71099462d5ecf..026214e7e2eac 100644 --- a/llvm/lib/TargetParser/AArch64TargetParser.cpp +++ b/llvm/lib/TargetParser/AArch64TargetParser.cpp @@ -280,3 +280,8 @@ bool AArch64::ExtensionSet::parseModifier(StringRef Modifier) { } return false; } + +const AArch64::ExtensionInfo & +AArch64::getExtensionByID(AArch64::ArchExtKind ExtID) { + return lookupExtensionByID(ExtID); +} diff --git a/llvm/lib/TargetParser/ARMTargetParserCommon.cpp b/llvm/lib/TargetParser/ARMTargetParserCommon.cpp index 45d04f9bcbfb6..d6ce6581bb1a9 100644 --- a/llvm/lib/TargetParser/ARMTargetParserCommon.cpp +++ b/llvm/lib/TargetParser/ARMTargetParserCommon.cpp @@ -139,7 +139,7 @@ ARM::EndianKind ARM::parseArchEndian(StringRef Arch) { // returned in `PBP`. Returns false in error, with `Err` containing // an erroneous part of the spec. bool ARM::parseBranchProtection(StringRef Spec, ParsedBranchProtection &PBP, - StringRef &Err) { + StringRef &Err, bool EnablePAuthLR) { PBP = {"none", "a_key", false, false, false}; if (Spec == "none") return true; // defaults are ok @@ -148,6 +148,7 @@ bool ARM::parseBranchProtection(StringRef Spec, ParsedBranchProtection &PBP, PBP.Scope = "non-leaf"; PBP.BranchTargetEnforcement = true; PBP.GuardedControlStack = true; + PBP.BranchProtectionPAuthLR = EnablePAuthLR; return true; } _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits