Hi Andrea, > -----Original Message----- > From: Gcc-patches <gcc-patches- > bounces+kyrylo.tkachov=arm....@gcc.gnu.org> On Behalf Of Andrea > Corallo via Gcc-patches > Sent: Friday, August 12, 2022 4:31 PM > To: Andrea Corallo via Gcc-patches <gcc-patches@gcc.gnu.org> > Cc: Richard Earnshaw <richard.earns...@arm.com>; nd <n...@arm.com> > Subject: [PATCH 7/15] arm: Emit build attributes for PACBTI target feature > > This patch emits assembler directives for PACBTI build attributes as > defined by the > ABI. > > <https://github.com/ARM-software/abi- > aa/releases/download/2021Q1/addenda32.pdf> > > gcc/ChangeLog: > > * config/arm/arm.c (arm_file_start): Emit EABI attributes for > Tag_PAC_extension, Tag_BTI_extension, TAG_BTI_use, > TAG_PACRET_use. > > gcc/testsuite/ChangeLog: > > * gcc.target/arm/acle/pacbti-m-predef-1.c: New test. > * gcc.target/arm/acle/pacbti-m-predef-3: Likewise. > * gcc.target/arm/acle/pacbti-m-predef-6.c: Likewise. > * gcc.target/arm/acle/pacbti-m-predef-7.c: Likewise. > > Co-Authored-By: Tejas Belagod <tbela...@arm.com>
diff --git a/gcc/config/arm/arm.cc b/gcc/config/arm/arm.cc index 0068817b0f2..ceec14f84b6 100644 --- a/gcc/config/arm/arm.cc +++ b/gcc/config/arm/arm.cc @@ -28349,6 +28349,8 @@ static void arm_file_start (void) { int val; + bool pac = (aarch_ra_sign_scope != AARCH_FUNCTION_NONE); + bool bti = (aarch_enable_bti == 1); arm_print_asm_arch_directives (asm_out_file, TREE_TARGET_OPTION (target_option_default_node)); @@ -28419,6 +28421,22 @@ arm_file_start (void) arm_emit_eabi_attribute ("Tag_ABI_FP_16bit_format", 38, (int) arm_fp16_format); + if (TARGET_HAVE_PACBTI) + { + arm_emit_eabi_attribute ("Tag_PAC_extension", 50, 2); + arm_emit_eabi_attribute ("Tag_BTI_extension", 52, 2); + } + else if (pac || bti) + { + arm_emit_eabi_attribute ("Tag_PAC_extension", 50, 1); + arm_emit_eabi_attribute ("Tag_BTI_extension", 52, 1); + } This hunk will set both Tag_PAC_extension and Tag_BTI_extension if only one of pac or bti is on. Is that intended? Would it makes sense to instead set the two Tag_*_extension tags individually as in the hunk below? + + if (bti) + arm_emit_eabi_attribute ("TAG_BTI_use", 74, 1); + if (pac) + arm_emit_eabi_attribute ("TAG_PACRET_use", 76, 1); + if (arm_lang_output_object_attributes_hook) arm_lang_output_object_attributes_hook(); } Thanks, Kyrill