[7/15] arm: Emit build attributes for PACBTI target feature
Commit Message
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 <tbelagod@arm.com>
Comments
Andrea Corallo via Gcc-patches <gcc-patches@gcc.gnu.org> writes:
> 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 <tbelagod@arm.com>
Ping
Andrea
Hi Andrea,
> -----Original Message-----
> From: Gcc-patches <gcc-patches-
> bounces+kyrylo.tkachov=arm.com@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.Earnshaw@arm.com>; nd <nd@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 <tbelagod@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
On 20/10/2022 15:47, Kyrylo Tkachov via Gcc-patches wrote:
> Hi Andrea,
>
>> -----Original Message-----
>> From: Gcc-patches <gcc-patches-
>> bounces+kyrylo.tkachov=arm.com@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.Earnshaw@arm.com>; nd <nd@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 <tbelagod@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?
That's because they are one feature in armv8-m and these tags describe
the presence of the feature in the architecture.
> +
> + if (bti)
> + arm_emit_eabi_attribute ("TAG_BTI_use", 74, 1);
> + if (pac)
> + arm_emit_eabi_attribute ("TAG_PACRET_use", 76, 1);
> +
But this describes /use/ by the code of each feature.
R.
> if (arm_lang_output_object_attributes_hook)
> arm_lang_output_object_attributes_hook();
> }
>
> Thanks,
> Kyrill
>
On 12/08/2022 16:30, Andrea Corallo via Gcc-patches wrote:
> 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 <tbelagod@arm.com>
>
OK.
R.
@@ -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);
+ }
+
+ 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();
}
new file mode 100644
@@ -0,0 +1,17 @@
+/* { dg-do compile } */
+/* { dg-require-effective-target mbranch_protection_ok } */
+/* { dg-options "-march=armv8.1-m.main+fp -mbranch-protection=pac-ret+bti -mfloat-abi=hard --save-temps" } */
+
+#if !defined (__ARM_FEATURE_BTI_DEFAULT)
+#error "Feature test macro __ARM_FEATURE_BTI_DEFAULT should be defined."
+#endif
+
+#if !defined (__ARM_FEATURE_PAC_DEFAULT)
+#error "Feature test macro __ARM_FEATURE_PAC_DEFAULT should be defined."
+#endif
+
+/* { dg-final { scan-assembler-not "\.arch_extension pacbti" } } */
+/* { dg-final { scan-assembler "\.eabi_attribute 50, 1" } } */
+/* { dg-final { scan-assembler "\.eabi_attribute 52, 1" } } */
+/* { dg-final { scan-assembler "\.eabi_attribute 74, 1" } } */
+/* { dg-final { scan-assembler "\.eabi_attribute 76, 1" } } */
new file mode 100644
@@ -0,0 +1,17 @@
+/* { dg-do compile } */
+/* { dg-require-effective-target mbranch_protection_ok } */
+/* { dg-options "-march=armv8.1-m.main+fp -mbranch-protection=pac-ret+leaf -mfloat-abi=hard --save-temps" } */
+
+#if defined (__ARM_FEATURE_BTI_DEFAULT)
+#error "Feature test macro __ARM_FEATURE_BTI_DEFAULT should be undefined."
+#endif
+
+#if !defined (__ARM_FEATURE_PAC_DEFAULT)
+#error "Feature test macro __ARM_FEATURE_PAC_DEFAULT should be defined."
+#endif
+
+/* { dg-final { scan-assembler-not "\.arch_extension pacbti" } } */
+/* { dg-final { scan-assembler "\.eabi_attribute 50, 1" } } */
+/* { dg-final { scan-assembler "\.eabi_attribute 52, 1" } } */
+/* { dg-final { scan-assembler-not "\.eabi_attribute 74" } } */
+/* { dg-final { scan-assembler "\.eabi_attribute 76, 1" } } */
new file mode 100644
@@ -0,0 +1,16 @@
+/* { dg-do compile } */
+/* { dg-require-effective-target mbranch_protection_ok } */
+/* { dg-additional-options "-march=armv8.1-m.main+fp -mbranch-protection=bti -mfloat-abi=hard --save-temps" } */
+
+#if !defined (__ARM_FEATURE_BTI_DEFAULT)
+#error "Feature test macro __ARM_FEATURE_BTI_DEFAULT should be defined."
+#endif
+
+#if defined (__ARM_FEATURE_PAC_DEFAULT)
+#error "Feature test macro __ARM_FEATURE_PAC_DEFAULT should be undefined."
+#endif
+/* { dg-final { scan-assembler-not "\.arch_extension pacbti" } } */
+/* { dg-final { scan-assembler "\.eabi_attribute 50, 1" } } */
+/* { dg-final { scan-assembler "\.eabi_attribute 52, 1" } } */
+/* { dg-final { scan-assembler "\.eabi_attribute 74, 1" } } */
+/* { dg-final { scan-assembler-not "\.eabi_attribute 76" } } */
new file mode 100644
@@ -0,0 +1,17 @@
+/* { dg-do compile } */
+/* { dg-skip-if "avoid conflicting multilib options" { *-*-* } { "-marm" "-mcpu=*" } } */
+/* { dg-additional-options "-march=armv8.1-m.main+pacbti+fp --save-temps -mfloat-abi=hard" } */
+
+#if defined (__ARM_FEATURE_BTI_DEFAULT)
+#error "Feature test macro __ARM_FEATURE_BTI_DEFAULT should be undefined."
+#endif
+
+#if defined (__ARM_FEATURE_PAC_DEFAULT)
+#error "Feature test macro __ARM_FEATURE_PAC_DEFAULT should be undefined."
+#endif
+
+/* { dg-final { scan-assembler "\.arch_extension pacbti" } } */
+/* { dg-final { scan-assembler "\.eabi_attribute 50, 2" } } */
+/* { dg-final { scan-assembler "\.eabi_attribute 52, 2" } } */
+/* { dg-final { scan-assembler-not "\.eabi_attribute 74" } } */
+/* { dg-final { scan-assembler-not "\.eabi_attribute 76" } } */