[clang] [Clang][AArch64] Add support for SHF_AARCH64_PURECODE ELF section flag (2/3) (PR #125688)
Csanád Hajdú via cfe-commits
cfe-commits at lists.llvm.org
Tue Feb 18 01:22:57 PST 2025
https://github.com/Il-Capitano updated https://github.com/llvm/llvm-project/pull/125688
>From a25845dcb484514c83022a21ee924e31a39882f4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Csan=C3=A1d=20Hajd=C3=BA?= <csanad.hajdu at arm.com>
Date: Tue, 4 Feb 2025 14:51:55 +0100
Subject: [PATCH 1/2] [Clang][AArch64] Add support for SHF_AARCH64_PURECODE ELF
section flag (2/3)
Add support for the new SHF_AARCH64_PURECODE ELF section flag: https://github.com/ARM-software/abi-aa/pull/304
The general implementation follows the existing one for ARM targets.
Simlarly to ARM targets, generating object files with the
`SHF_AARCH64_PURECODE` flag set is enabled by the
`-mexecute-only`/`-mpure-code` driver flag.
---
clang/include/clang/Driver/Options.td | 4 ++--
clang/lib/Driver/ToolChains/Arch/AArch64.cpp | 11 +++++++++
clang/test/CodeGen/aarch64-execute-only.c | 24 ++++++++++++++++++++
clang/test/Driver/aarch64-execute-only.c | 6 +++++
clang/test/Driver/fsanitize.c | 8 ++++++-
5 files changed, 50 insertions(+), 3 deletions(-)
create mode 100644 clang/test/CodeGen/aarch64-execute-only.c
create mode 100644 clang/test/Driver/aarch64-execute-only.c
diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
index 5ad187926e710..0c8c4e5e0fae4 100644
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -4692,9 +4692,9 @@ def mno_long_calls : Flag<["-"], "mno-long-calls">, Group<m_Group>,
HelpText<"Restore the default behaviour of not generating long calls">;
} // let Flags = [TargetSpecific]
def mexecute_only : Flag<["-"], "mexecute-only">, Group<m_arm_Features_Group>,
- HelpText<"Disallow generation of data access to code sections (ARM only)">;
+ HelpText<"Disallow generation of data access to code sections (AArch64/ARM only)">;
def mno_execute_only : Flag<["-"], "mno-execute-only">, Group<m_arm_Features_Group>,
- HelpText<"Allow generation of data access to code sections (ARM only)">;
+ HelpText<"Allow generation of data access to code sections (AArch64/ARM only)">;
let Flags = [TargetSpecific] in {
def mtp_mode_EQ : Joined<["-"], "mtp=">, Group<m_arm_Features_Group>, Values<"soft,cp15,tpidrurw,tpidruro,tpidrprw,el0,el1,el2,el3,tpidr_el0,tpidr_el1,tpidr_el2,tpidr_el3,tpidrro_el0">,
HelpText<"Thread pointer access method. "
diff --git a/clang/lib/Driver/ToolChains/Arch/AArch64.cpp b/clang/lib/Driver/ToolChains/Arch/AArch64.cpp
index 1e2ac4e501baf..1248fea50f9de 100644
--- a/clang/lib/Driver/ToolChains/Arch/AArch64.cpp
+++ b/clang/lib/Driver/ToolChains/Arch/AArch64.cpp
@@ -332,6 +332,17 @@ void aarch64::getAArch64TargetFeatures(const Driver &D,
} else if (Triple.isOSOpenBSD())
Features.push_back("+strict-align");
+ // Generate execute-only output (no data access to code sections).
+ // This only makes sense for the compiler, not for the assembler.
+ if (!ForAS) {
+ if (Arg *A = Args.getLastArg(options::OPT_mexecute_only,
+ options::OPT_mno_execute_only)) {
+ if (A->getOption().matches(options::OPT_mexecute_only)) {
+ Features.push_back("+execute-only");
+ }
+ }
+ }
+
if (Args.hasArg(options::OPT_ffixed_x1))
Features.push_back("+reserve-x1");
diff --git a/clang/test/CodeGen/aarch64-execute-only.c b/clang/test/CodeGen/aarch64-execute-only.c
new file mode 100644
index 0000000000000..d885e954166f6
--- /dev/null
+++ b/clang/test/CodeGen/aarch64-execute-only.c
@@ -0,0 +1,24 @@
+// RUN: %clang -target aarch64 -### %s 2>&1 \
+// RUN: | FileCheck %s -check-prefix CHECK-NO-EXECUTE-ONLY
+
+// RUN: %clang -target aarch64 -### -mexecute-only %s 2>&1 \
+// RUN: | FileCheck %s -check-prefix CHECK-EXECUTE-ONLY
+
+// RUN: %clang -target aarch64 -### -mexecute-only -mno-execute-only %s 2>&1 \
+// RUN: | FileCheck %s -check-prefix CHECK-NO-EXECUTE-ONLY
+
+
+// -mpure-code flag for GCC compatibility
+// RUN: %clang -target aarch64 -### %s 2>&1 \
+// RUN: | FileCheck %s -check-prefix CHECK-NO-EXECUTE-ONLY
+
+// RUN: %clang -target aarch64 -### -mpure-code %s 2>&1 \
+// RUN: | FileCheck %s -check-prefix CHECK-EXECUTE-ONLY
+
+// RUN: %clang -target aarch64 -### -mpure-code -mno-pure-code %s 2>&1 \
+// RUN: | FileCheck %s -check-prefix CHECK-NO-EXECUTE-ONLY
+
+// CHECK-NO-EXECUTE-ONLY-NOT: "+execute-only"
+// CHECK-EXECUTE-ONLY: "+execute-only"
+
+void a() {}
diff --git a/clang/test/Driver/aarch64-execute-only.c b/clang/test/Driver/aarch64-execute-only.c
new file mode 100644
index 0000000000000..67c6d4a5eb066
--- /dev/null
+++ b/clang/test/Driver/aarch64-execute-only.c
@@ -0,0 +1,6 @@
+// RUN: %clang --sysroot=%S/Inputs -c -fdriver-only -Werror --target=aarch64-unknown-linux-gnu \
+// RUN: -mexecute-only %s 2>&1 | count 0
+
+// RUN: %clang -### --target=aarch64-unknown-linux-gnu -x assembler -mexecute-only %s -c -### 2>&1 \
+// RUN: | FileCheck %s --check-prefix=CHECK-NO-EXECUTE-ONLY-ASM
+// CHECK-NO-EXECUTE-ONLY-ASM: warning: argument unused during compilation: '-mexecute-only'
diff --git a/clang/test/Driver/fsanitize.c b/clang/test/Driver/fsanitize.c
index 429dc51b3356d..cb3b75cbd27a7 100644
--- a/clang/test/Driver/fsanitize.c
+++ b/clang/test/Driver/fsanitize.c
@@ -1052,7 +1052,6 @@
// RUN: not %clang --target=x86_64-sie-ps5 -fsanitize=kcfi %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-UBSAN-KCFI-TARGET
// RUN: not %clang --target=x86_64-sie-ps5 -fsanitize=function -fsanitize=kcfi %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-UBSAN-KCFI-TARGET --check-prefix=CHECK-UBSAN-FUNCTION-TARGET
// RUN: %clang --target=x86_64-sie-ps5 -fsanitize=undefined %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-UBSAN-UNDEFINED
-// CHECK-UBSAN-UNDEFINED: "-fsanitize={{((alignment|array-bounds|bool|builtin|enum|float-cast-overflow|integer-divide-by-zero|nonnull-attribute|null|pointer-overflow|return|returns-nonnull-attribute|shift-base|shift-exponent|signed-integer-overflow|unreachable|vla-bound),?){17}"}}
// RUN: not %clang --target=armv6t2-eabi -mexecute-only -fsanitize=function %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-UBSAN-FUNCTION-MEXECUTE-ONLY
// RUN: not %clang --target=armv6t2-eabi -mpure-code -fsanitize=function %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-UBSAN-FUNCTION-MPURE-CODE
@@ -1060,12 +1059,19 @@
// RUN: not %clang --target=armv6t2-eabi -mpure-code -fsanitize=kcfi %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-UBSAN-KCFI-MPURE-CODE
// RUN: %clang --target=armv6t2-eabi -mexecute-only -fsanitize=undefined %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-UBSAN-UNDEFINED-VPTR
+// RUN: not %clang --target=aarch64 -mexecute-only -fsanitize=function %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-UBSAN-FUNCTION-MEXECUTE-ONLY
+// RUN: not %clang --target=aarch64 -mpure-code -fsanitize=function %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-UBSAN-FUNCTION-MPURE-CODE
+// RUN: not %clang --target=aarch64 -mexecute-only -fsanitize=kcfi %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-UBSAN-KCFI-MEXECUTE-ONLY
+// RUN: not %clang --target=aarch64 -mpure-code -fsanitize=kcfi %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-UBSAN-KCFI-MPURE-CODE
+// RUN: %clang --target=aarch64 -mexecute-only -fsanitize=undefined %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-UBSAN-UNDEFINED
+
// CHECK-UBSAN-KCFI-TARGET-DAG: error: unsupported option '-fsanitize=kcfi' for target 'x86_64-sie-ps5'
// CHECK-UBSAN-KCFI-MEXECUTE-ONLY-DAG: error: invalid argument '-fsanitize=kcfi' not allowed with '-mexecute-only'
// CHECK-UBSAN-KCFI-MPURE-CODE-DAG: error: invalid argument '-fsanitize=kcfi' not allowed with '-mpure-code'
// CHECK-UBSAN-FUNCTION-TARGET-DAG: error: unsupported option '-fsanitize=function' for target 'x86_64-sie-ps5'
// CHECK-UBSAN-FUNCTION-MEXECUTE-ONLY-DAG: error: invalid argument '-fsanitize=function' not allowed with '-mexecute-only'
// CHECK-UBSAN-FUNCTION-MPURE-CODE-DAG: error: invalid argument '-fsanitize=function' not allowed with '-mpure-code'
+// CHECK-UBSAN-UNDEFINED: "-fsanitize={{((alignment|array-bounds|bool|builtin|enum|float-cast-overflow|integer-divide-by-zero|nonnull-attribute|null|pointer-overflow|return|returns-nonnull-attribute|shift-base|shift-exponent|signed-integer-overflow|unreachable|vla-bound),?){17}"}}
// CHECK-UBSAN-UNDEFINED-VPTR: "-fsanitize={{((alignment|array-bounds|bool|builtin|enum|float-cast-overflow|integer-divide-by-zero|nonnull-attribute|null|pointer-overflow|return|returns-nonnull-attribute|shift-base|shift-exponent|signed-integer-overflow|unreachable|vla-bound|vptr),?){18}"}}
// * Test BareMetal toolchain sanitizer support *
>From 3fb9937a2587eac98f5e83848d08a182cc7d2750 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Csan=C3=A1d=20Hajd=C3=BA?= <csanad.hajdu at arm.com>
Date: Tue, 18 Feb 2025 10:19:58 +0100
Subject: [PATCH 2/2] Fix unused argument diagnostic emission for baremetal
targets
---
clang/lib/Driver/ToolChain.cpp | 4 +++-
clang/lib/Driver/ToolChains/Arch/AArch64.cpp | 6 ++++--
clang/lib/Driver/ToolChains/Arch/AArch64.h | 2 +-
clang/test/Driver/aarch64-execute-only.c | 3 +++
4 files changed, 11 insertions(+), 4 deletions(-)
diff --git a/clang/lib/Driver/ToolChain.cpp b/clang/lib/Driver/ToolChain.cpp
index 56bc500da66b9..f116679fbe49b 100644
--- a/clang/lib/Driver/ToolChain.cpp
+++ b/clang/lib/Driver/ToolChain.cpp
@@ -210,7 +210,9 @@ static void getAArch64MultilibFlags(const Driver &D,
const llvm::opt::ArgList &Args,
Multilib::flags_list &Result) {
std::vector<StringRef> Features;
- tools::aarch64::getAArch64TargetFeatures(D, Triple, Args, Features, false);
+ tools::aarch64::getAArch64TargetFeatures(D, Triple, Args, Features,
+ /*ForAS=*/false,
+ /*ForMultilib=*/true);
const auto UnifiedFeatures = tools::unifyTargetFeatures(Features);
llvm::DenseSet<StringRef> FeatureSet(UnifiedFeatures.begin(),
UnifiedFeatures.end());
diff --git a/clang/lib/Driver/ToolChains/Arch/AArch64.cpp b/clang/lib/Driver/ToolChains/Arch/AArch64.cpp
index 1248fea50f9de..6e70effe9e325 100644
--- a/clang/lib/Driver/ToolChains/Arch/AArch64.cpp
+++ b/clang/lib/Driver/ToolChains/Arch/AArch64.cpp
@@ -196,7 +196,7 @@ void aarch64::getAArch64TargetFeatures(const Driver &D,
const llvm::Triple &Triple,
const ArgList &Args,
std::vector<StringRef> &Features,
- bool ForAS) {
+ bool ForAS, bool ForMultilib) {
Arg *A;
bool success = true;
llvm::StringRef WaMArch;
@@ -334,7 +334,9 @@ void aarch64::getAArch64TargetFeatures(const Driver &D,
// Generate execute-only output (no data access to code sections).
// This only makes sense for the compiler, not for the assembler.
- if (!ForAS) {
+ // It's not needed for multilib selection and may hide an unused
+ // argument diagnostic if the code is always run.
+ if (!ForAS && !ForMultilib) {
if (Arg *A = Args.getLastArg(options::OPT_mexecute_only,
options::OPT_mno_execute_only)) {
if (A->getOption().matches(options::OPT_mexecute_only)) {
diff --git a/clang/lib/Driver/ToolChains/Arch/AArch64.h b/clang/lib/Driver/ToolChains/Arch/AArch64.h
index 6d071167bd392..2057272867a17 100644
--- a/clang/lib/Driver/ToolChains/Arch/AArch64.h
+++ b/clang/lib/Driver/ToolChains/Arch/AArch64.h
@@ -23,7 +23,7 @@ namespace aarch64 {
void getAArch64TargetFeatures(const Driver &D, const llvm::Triple &Triple,
const llvm::opt::ArgList &Args,
std::vector<llvm::StringRef> &Features,
- bool ForAS);
+ bool ForAS, bool ForMultilib = false);
std::string getAArch64TargetCPU(const llvm::opt::ArgList &Args,
const llvm::Triple &Triple, llvm::opt::Arg *&A);
diff --git a/clang/test/Driver/aarch64-execute-only.c b/clang/test/Driver/aarch64-execute-only.c
index 67c6d4a5eb066..e7d0949f09d13 100644
--- a/clang/test/Driver/aarch64-execute-only.c
+++ b/clang/test/Driver/aarch64-execute-only.c
@@ -3,4 +3,7 @@
// RUN: %clang -### --target=aarch64-unknown-linux-gnu -x assembler -mexecute-only %s -c -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-NO-EXECUTE-ONLY-ASM
+// RUN: %clang -### --multi-lib-config=%S/Inputs/multilib/empty.yaml --sysroot= \
+// RUN: --target=aarch64-none-elf -x assembler -mexecute-only %s -c -### 2>&1 \
+// RUN: | FileCheck %s --check-prefix=CHECK-NO-EXECUTE-ONLY-ASM
// CHECK-NO-EXECUTE-ONLY-ASM: warning: argument unused during compilation: '-mexecute-only'
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