Message ID | PAXPR08MB7075F6901E0E4C361E77C06BEA869@PAXPR08MB7075.eurprd08.prod.outlook.com |
---|---|
State | New |
Headers | show |
Series | [1/8,Arm,AArch64] Refactor mbranch-protection option parsing and make it common to AArch32 and AArch64 backends. [Was RE: [Patch 2/7, Arm, GCC] Add option -mbranch-protection.] | expand |
On 28/10/2021 12:43, Tejas Belagod via Gcc-patches wrote: > > >> -----Original Message----- >> From: Richard Earnshaw <Richard.Earnshaw@arm.com> >> Sent: Monday, October 11, 2021 2:58 PM >> To: Tejas Belagod <Tejas.Belagod@arm.com>; gcc-patches@gcc.gnu.org >> Subject: Re: [Patch 4/7, Arm. GCC] Implement target feature macros for >> PACBTI. >> >> On 08/10/2021 13:18, Tejas Belagod via Gcc-patches wrote: >>> Hi, >>> >>> This patch implements target feature macros when PACBTI is enabled >>> through the -march option or -mbranch-protection. >>> >>> Tested on arm-none-eabi. OK for trunk? >>> >>> 2021-10-04 Tejas Belagod <tbelagod@arm.com> >>> >>> gcc/ChangeLog: >>> >>> * config/arm/arm-c.c (arm_cpu_builtins): Define >>> __ARM_FEATURE_BTI_DEFAULT and >> __ARM_FEATURE_PAC_DEFAULT. >>> >>> gcc/testsuite/ChangeLog: >>> >>> * gcc.target/arm/acle/pacbti-m-predef-2.c: New test. >>> * gcc.target/arm/acle/pacbti-m-predef-4.c: New test. >>> * gcc.target/arm/acle/pacbti-m-predef-5.c: New test. >>> >> >> I presume the specification for this is ACLE - please say so rather than making >> me guess. >> > > Yes, sorry, very poor description on my part. Now fixed - please see patch description below for links to specific ACLE sections. > >> >> + cpp_undef (pfile, "__ARM_FEATURE_BTI_DEFAULT"); >> + cpp_undef (pfile, "__ARM_FEATURE_PAC_DEFAULT"); >> + if (TARGET_HAVE_PACBTI) >> + { >> + builtin_define_with_int_value ("__ARM_FEATURE_BTI_DEFAULT", >> + arm_enable_pacbti & 0x1); >> >> My reading of the ACLE specification would suggest this shouldn't be >> defined if it would have a value of 0, but that's not what this code >> does. I think it would be better to move this outside the >> TARGET_HAVE_PACBTI and use the def_or_undef approach. >> >> + builtin_define_with_int_value ("__ARM_FEATURE_PAC_DEFAULT", >> + arm_enable_pacbti >> 1); >> >> This one is less clear, could the value ever be zero? I guess exactly >> one of a-key and b-key must be defined and each has a separate bit. >> > > Now fixed according to what the arch specifies. For the M-profile, there's only one key which means when -mbranch-protection is invoked, bit 0 is always 1. > >> + } >> + >> + >> >> Not more than one blank line at the end of a block. >> >> >> diff --git a/gcc/testsuite/gcc.target/arm/acle/pacbti-m-predef-2.c >> b/gcc/testsuite/gcc.target/arm/acle/pacbti-m-predef-2.c >> >> >> Given what I've said above, I think you need to also test that >> __ARM_FEATURE_BTI_DEFAULT is defined before testing the value (and >> emitting #error if it isn't). >> > > Fixed. > > This patch implements target feature macros when PACBTI is > enabled through the -march option or -mbranch-protection. > The target feature macros __ARM_FEATURE_PAC_DEFAULT and > __ARM_FEATURE_BTI_DEFAULT are specified in ARM ACLE > (https://developer.arm.com/documentation/101028/0012/5--Feature-test-macros?lang=en) > __ARM_FEATURE_PAUTH and __ARM_FEATURE_BTI are specified in the pull-request > (https://github.com/ARM-software/acle/pull/55). > > 2021-10-25 Tejas Belagod <tbelagod@arm.com> > > gcc/ChangeLog: > > * config/arm/arm-c.c (arm_cpu_builtins): Define > __ARM_FEATURE_BTI_DEFAULT, __ARM_FEATURE_PAC_DEFAULT, > __ARM_FEATURE_PAUTH and __ARM_FEATURE_BTI. > > gcc/testsuite/ChangeLog: > > * gcc.target/arm/acle/pacbti-m-predef-2.c: New test. > * gcc.target/arm/acle/pacbti-m-predef-4.c: New test. > * gcc.target/arm/acle/pacbti-m-predef-5.c: New test. > > Tested the following configurations, OK for trunk? > > -mthumb/-march=armv8.1-m.main+pacbti/-mfloat-abi=soft > -marm/-march=armv7-a/-mfpu=vfpv3-d16/-mfloat-abi=softfp > mcmodel=small and tiny > aarch64-none-linux-gnu native test and bootstrap > > Thanks, > Tejas. > OK. R.
diff --git a/gcc/config/arm/arm-c.c b/gcc/config/arm/arm-c.c index cc7901bca8dc9c5c27ed6afc5bc26afd42689e6d..98d47ad4cc6e88aa7401429a809c555c5aadc15f 100644 --- a/gcc/config/arm/arm-c.c +++ b/gcc/config/arm/arm-c.c @@ -193,6 +193,24 @@ arm_cpu_builtins (struct cpp_reader* pfile) def_or_undef_macro (pfile, "__ARM_FEATURE_COMPLEX", TARGET_COMPLEX); def_or_undef_macro (pfile, "__ARM_32BIT_STATE", TARGET_32BIT); + def_or_undef_macro (pfile, "__ARM_FEATURE_PAUTH", TARGET_HAVE_PACBTI); + def_or_undef_macro (pfile, "__ARM_FEATURE_BTI", TARGET_HAVE_PACBTI); + def_or_undef_macro (pfile, "__ARM_FEATURE_BTI_DEFAULT", + aarch_enable_bti == 1); + + cpp_undef (pfile, "__ARM_FEATURE_PAC_DEFAULT"); + if (aarch_ra_sign_scope != AARCH_FUNCTION_NONE) + { + unsigned int pac = 1; + + gcc_assert (aarch_ra_sign_key == AARCH_KEY_A); + + if (aarch_ra_sign_scope == AARCH_FUNCTION_ALL) + pac |= 0x4; + + builtin_define_with_int_value ("__ARM_FEATURE_PAC_DEFAULT", pac); + } + cpp_undef (pfile, "__ARM_FEATURE_MVE"); if (TARGET_HAVE_MVE && TARGET_HAVE_MVE_FLOAT) { diff --git a/gcc/testsuite/gcc.target/arm/acle/pacbti-m-predef-2.c b/gcc/testsuite/gcc.target/arm/acle/pacbti-m-predef-2.c new file mode 100644 index 0000000000000000000000000000000000000000..4394fd147d7bf468238bd66a24b79bd1338d33aa --- /dev/null +++ b/gcc/testsuite/gcc.target/arm/acle/pacbti-m-predef-2.c @@ -0,0 +1,24 @@ + +/* { dg-do run } */ +/* { dg-require-effective-target arm_pacbti_hw } */ +/* { dg-additional-options " -mbranch-protection=bti+pac-ret+leaf" } */ + +#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 + +int +main() +{ + if (__ARM_FEATURE_BTI_DEFAULT != 1) + __builtin_abort (); + + if (__ARM_FEATURE_PAC_DEFAULT != 5) + __builtin_abort (); + + return 0; +} diff --git a/gcc/testsuite/gcc.target/arm/acle/pacbti-m-predef-4.c b/gcc/testsuite/gcc.target/arm/acle/pacbti-m-predef-4.c new file mode 100644 index 0000000000000000000000000000000000000000..90f0c724b9efe38d3c3a1345d49a9615b853207e --- /dev/null +++ b/gcc/testsuite/gcc.target/arm/acle/pacbti-m-predef-4.c @@ -0,0 +1,21 @@ + +/* { dg-do run } */ +/* { dg-require-effective-target arm_pacbti_hw } */ +/* { dg-additional-options " -mbranch-protection=pac-ret" } */ + +#if !defined (__ARM_FEATURE_PAC_DEFAULT) +#error "Feature test macro __ARM_FEATURE_BTI_DEFAULT should be defined." +#endif + +#if defined (__ARM_FEATURE_BTI_DEFAULT) +#error "Feature test macro __ARM_FEATURE_BTI_DEFAULT should be undefined." +#endif + +int +main() +{ + if (__ARM_FEATURE_PAC_DEFAULT != 1) + __builtin_abort (); + + return 0; +} diff --git a/gcc/testsuite/gcc.target/arm/acle/pacbti-m-predef-5.c b/gcc/testsuite/gcc.target/arm/acle/pacbti-m-predef-5.c new file mode 100644 index 0000000000000000000000000000000000000000..c865809b8b01db8f8c021501e7d3317b0b8bb0ed --- /dev/null +++ b/gcc/testsuite/gcc.target/arm/acle/pacbti-m-predef-5.c @@ -0,0 +1,24 @@ + +/* { dg-do run } */ +/* { dg-require-effective-target arm_pacbti_hw } */ +/* { dg-additional-options " -mbranch-protection=bti+pac-ret" } */ + +#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 + +int +main() +{ + if (__ARM_FEATURE_BTI_DEFAULT != 1) + __builtin_abort (); + + if (__ARM_FEATURE_PAC_DEFAULT != 1) + __builtin_abort (); + + return 0; +}