RE: [PATCH][GCC][AArch64] Ensure that outgoing argument size is at least 8 bytes when alloca and stack-clash. [Patch (3/6)]
Hi All, I'm looking for permission to backport this patch to the GCC-8 branch to fix PR86486. OK for backport? Thanks, Tamar > -Original Message- > From: James Greenhalgh > Sent: Tuesday, August 7, 2018 17:18 > To: Tamar Christina > Cc: Jeff Law ; gcc-patches@gcc.gnu.org; nd > ; Richard Earnshaw ; Marcus > Shawcroft > Subject: Re: [PATCH][GCC][AArch64] Ensure that outgoing argument size is at > least 8 bytes when alloca and stack-clash. [Patch (3/6)] > > On Tue, Aug 07, 2018 at 05:09:34AM -0500, Tamar Christina wrote: > > Hi All, > > > > This is a re-spin to address review comments. No code change aside from a > variable rename. > > > > Ok for trunk? > > OK. > > Thanks, > James > > > gcc/ > > 2018-08-07 Tamar Christina > > > > PR target/86486 > > * config/aarch64/aarch64.h > (STACK_CLASH_MIN_BYTES_OUTGOING_ARGS, > > STACK_DYNAMIC_OFFSET): New. > > * config/aarch64/aarch64.c (aarch64_layout_frame): > > Update outgoing args size. > > (aarch64_stack_clash_protection_alloca_probe_range, > > TARGET_STACK_CLASH_PROTECTION_ALLOCA_PROBE_RANGE): > New. > > > > gcc/testsuite/ > > 2018-08-07 Tamar Christina > > > > PR target/86486 > > * gcc.target/aarch64/stack-check-alloca-1.c: New. > > * gcc.target/aarch64/stack-check-alloca-10.c: New. > > * gcc.target/aarch64/stack-check-alloca-2.c: New. > > * gcc.target/aarch64/stack-check-alloca-3.c: New. > > * gcc.target/aarch64/stack-check-alloca-4.c: New. > > * gcc.target/aarch64/stack-check-alloca-5.c: New. > > * gcc.target/aarch64/stack-check-alloca-6.c: New. > > * gcc.target/aarch64/stack-check-alloca-7.c: New. > > * gcc.target/aarch64/stack-check-alloca-8.c: New. > > * gcc.target/aarch64/stack-check-alloca-9.c: New. > > * gcc.target/aarch64/stack-check-alloca.h: New. > > * gcc.target/aarch64/stack-check-14.c: New. > > * gcc.target/aarch64/stack-check-15.c: New.
Re: [PATCH][GCC][AArch64] Ensure that outgoing argument size is at least 8 bytes when alloca and stack-clash. [Patch (3/6)]
On Tue, Aug 07, 2018 at 05:09:34AM -0500, Tamar Christina wrote: > Hi All, > > This is a re-spin to address review comments. No code change aside from a > variable rename. > > Ok for trunk? OK. Thanks, James > gcc/ > 2018-08-07 Tamar Christina > > PR target/86486 > * config/aarch64/aarch64.h (STACK_CLASH_MIN_BYTES_OUTGOING_ARGS, > STACK_DYNAMIC_OFFSET): New. > * config/aarch64/aarch64.c (aarch64_layout_frame): > Update outgoing args size. > (aarch64_stack_clash_protection_alloca_probe_range, > TARGET_STACK_CLASH_PROTECTION_ALLOCA_PROBE_RANGE): New. > > gcc/testsuite/ > 2018-08-07 Tamar Christina > > PR target/86486 > * gcc.target/aarch64/stack-check-alloca-1.c: New. > * gcc.target/aarch64/stack-check-alloca-10.c: New. > * gcc.target/aarch64/stack-check-alloca-2.c: New. > * gcc.target/aarch64/stack-check-alloca-3.c: New. > * gcc.target/aarch64/stack-check-alloca-4.c: New. > * gcc.target/aarch64/stack-check-alloca-5.c: New. > * gcc.target/aarch64/stack-check-alloca-6.c: New. > * gcc.target/aarch64/stack-check-alloca-7.c: New. > * gcc.target/aarch64/stack-check-alloca-8.c: New. > * gcc.target/aarch64/stack-check-alloca-9.c: New. > * gcc.target/aarch64/stack-check-alloca.h: New. > * gcc.target/aarch64/stack-check-14.c: New. > * gcc.target/aarch64/stack-check-15.c: New.
RE: [PATCH][GCC][AArch64] Ensure that outgoing argument size is at least 8 bytes when alloca and stack-clash. [Patch (3/6)]
Hi All, This is a re-spin to address review comments. No code change aside from a variable rename. Ok for trunk? Thanks, Tamar gcc/ 2018-08-07 Tamar Christina PR target/86486 * config/aarch64/aarch64.h (STACK_CLASH_MIN_BYTES_OUTGOING_ARGS, STACK_DYNAMIC_OFFSET): New. * config/aarch64/aarch64.c (aarch64_layout_frame): Update outgoing args size. (aarch64_stack_clash_protection_alloca_probe_range, TARGET_STACK_CLASH_PROTECTION_ALLOCA_PROBE_RANGE): New. gcc/testsuite/ 2018-08-07 Tamar Christina PR target/86486 * gcc.target/aarch64/stack-check-alloca-1.c: New. * gcc.target/aarch64/stack-check-alloca-10.c: New. * gcc.target/aarch64/stack-check-alloca-2.c: New. * gcc.target/aarch64/stack-check-alloca-3.c: New. * gcc.target/aarch64/stack-check-alloca-4.c: New. * gcc.target/aarch64/stack-check-alloca-5.c: New. * gcc.target/aarch64/stack-check-alloca-6.c: New. * gcc.target/aarch64/stack-check-alloca-7.c: New. * gcc.target/aarch64/stack-check-alloca-8.c: New. * gcc.target/aarch64/stack-check-alloca-9.c: New. * gcc.target/aarch64/stack-check-alloca.h: New. * gcc.target/aarch64/stack-check-14.c: New. * gcc.target/aarch64/stack-check-15.c: New. > -Original Message- > From: Jeff Law > Sent: Friday, August 3, 2018 19:05 > To: Tamar Christina ; gcc-patches@gcc.gnu.org > Cc: nd ; James Greenhalgh ; > Richard Earnshaw ; Marcus Shawcroft > > Subject: Re: [PATCH][GCC][AArch64] Ensure that outgoing argument size is at > least 8 bytes when alloca and stack-clash. [Patch (3/6)] > > On 07/25/2018 05:09 AM, Tamar Christina wrote: > > Hi All, > > > > Attached an updated patch which documents what the test cases are > expecting as requested. > > > > Ok for trunk? > > > > Thanks, > > Tamar > > > > gcc/ > > 2018-07-25 Tamar Christina > > > > PR target/86486 > > * config/aarch64/aarch64.h (STACK_CLASH_OUTGOING_ARGS, > > STACK_DYNAMIC_OFFSET): New. > > * config/aarch64/aarch64.c (aarch64_layout_frame): > > Update outgoing args size. > > (aarch64_stack_clash_protection_alloca_probe_range, > > TARGET_STACK_CLASH_PROTECTION_ALLOCA_PROBE_RANGE): > New. > > > > gcc/testsuite/ > > 2018-07-25 Tamar Christina > > > > PR target/86486 > > * gcc.target/aarch64/stack-check-alloca-1.c: New. > > * gcc.target/aarch64/stack-check-alloca-10.c: New. > > * gcc.target/aarch64/stack-check-alloca-2.c: New. > > * gcc.target/aarch64/stack-check-alloca-3.c: New. > > * gcc.target/aarch64/stack-check-alloca-4.c: New. > > * gcc.target/aarch64/stack-check-alloca-5.c: New. > > * gcc.target/aarch64/stack-check-alloca-6.c: New. > > * gcc.target/aarch64/stack-check-alloca-7.c: New. > > * gcc.target/aarch64/stack-check-alloca-8.c: New. > > * gcc.target/aarch64/stack-check-alloca-9.c: New. > > * gcc.target/aarch64/stack-check-alloca.h: New. > > * gcc.target/aarch64/stack-check-14.c: New. > > * gcc.target/aarch64/stack-check-15.c: New. > > > >> -Original Message----- > >> From: Tamar Christina > >> Sent: Friday, July 13, 2018 17:36 > >> To: Tamar Christina ; > >> gcc-patches@gcc.gnu.org > >> Cc: nd ; James Greenhalgh > ; > >> Richard Earnshaw ; Marcus Shawcroft > >> > >> Subject: RE: [PATCH][GCC][AArch64] Ensure that outgoing argument size > >> is at least 8 bytes when alloca and stack-clash. [Patch (3/6)] > >> > >> Hi All, > >> > >> I'm sending an updated patch which updates a testcase that hits one > >> of our corner cases. > >> This is an assembler scan only update in a testcase. > >> > >> Regards, > >> Tamar > >> > >>> -Original Message- > >>> From: Tamar Christina > >>> Sent: Wednesday, July 11, 2018 12:21 > >>> To: gcc-patches@gcc.gnu.org > >>> Cc: nd ; James Greenhalgh > ; > >>> Richard Earnshaw ; Marcus Shawcroft > >>> > >>> Subject: [PATCH][GCC][AArch64] Ensure that outgoing argument size is > >>> at least 8 bytes when alloca and stack-clash. [Patch (3/6)] > >>> > >>> Hi All, > >>> > >>> This patch adds a requirement that the number of outgoing arguments > >>> for a function is at least 8 bytes when using stack-clash protection. > >>> > >>> By using this condition we can avo
Re: [PATCH][GCC][AArch64] Ensure that outgoing argument size is at least 8 bytes when alloca and stack-clash. [Patch (3/6)]
On 07/25/2018 05:09 AM, Tamar Christina wrote: > Hi All, > > Attached an updated patch which documents what the test cases are expecting > as requested. > > Ok for trunk? > > Thanks, > Tamar > > gcc/ > 2018-07-25 Tamar Christina > > PR target/86486 > * config/aarch64/aarch64.h (STACK_CLASH_OUTGOING_ARGS, > STACK_DYNAMIC_OFFSET): New. > * config/aarch64/aarch64.c (aarch64_layout_frame): > Update outgoing args size. > (aarch64_stack_clash_protection_alloca_probe_range, > TARGET_STACK_CLASH_PROTECTION_ALLOCA_PROBE_RANGE): New. > > gcc/testsuite/ > 2018-07-25 Tamar Christina > > PR target/86486 > * gcc.target/aarch64/stack-check-alloca-1.c: New. > * gcc.target/aarch64/stack-check-alloca-10.c: New. > * gcc.target/aarch64/stack-check-alloca-2.c: New. > * gcc.target/aarch64/stack-check-alloca-3.c: New. > * gcc.target/aarch64/stack-check-alloca-4.c: New. > * gcc.target/aarch64/stack-check-alloca-5.c: New. > * gcc.target/aarch64/stack-check-alloca-6.c: New. > * gcc.target/aarch64/stack-check-alloca-7.c: New. > * gcc.target/aarch64/stack-check-alloca-8.c: New. > * gcc.target/aarch64/stack-check-alloca-9.c: New. > * gcc.target/aarch64/stack-check-alloca.h: New. > * gcc.target/aarch64/stack-check-14.c: New. > * gcc.target/aarch64/stack-check-15.c: New. > >> -Original Message- >> From: Tamar Christina >> Sent: Friday, July 13, 2018 17:36 >> To: Tamar Christina ; gcc-patches@gcc.gnu.org >> Cc: nd ; James Greenhalgh ; >> Richard Earnshaw ; Marcus Shawcroft >> >> Subject: RE: [PATCH][GCC][AArch64] Ensure that outgoing argument size is at >> least 8 bytes when alloca and stack-clash. [Patch (3/6)] >> >> Hi All, >> >> I'm sending an updated patch which updates a testcase that hits one of our >> corner cases. >> This is an assembler scan only update in a testcase. >> >> Regards, >> Tamar >> >>> -Original Message- >>> From: Tamar Christina >>> Sent: Wednesday, July 11, 2018 12:21 >>> To: gcc-patches@gcc.gnu.org >>> Cc: nd ; James Greenhalgh ; >>> Richard Earnshaw ; Marcus Shawcroft >>> >>> Subject: [PATCH][GCC][AArch64] Ensure that outgoing argument size is >>> at least 8 bytes when alloca and stack-clash. [Patch (3/6)] >>> >>> Hi All, >>> >>> This patch adds a requirement that the number of outgoing arguments >>> for a function is at least 8 bytes when using stack-clash protection. >>> >>> By using this condition we can avoid a check in the alloca code and so >>> have smaller and simpler code there. >>> >>> A simplified version of the AArch64 stack frames is: >>> >>>+---+ >>>| | >>>| | >>>| | >>>+---+ >>>|LR | >>>+---+ >>>|FP | >>>+---+ >>>|dynamic allocations| expanding area which will push the >>> outgoing >>>+---+ args down during each allocation. >>>|padding| >>>+---+ >>>|outgoing stack args| safety buffer of 8 bytes (aligned) >>>+---+ >>> >>> By always defining an outgoing argument, alloca(0) effectively is safe >>> to probe at $sp due to the reserved buffer being there. It will never >>> corrupt the stack. >>> >>> This is also safe for alloca(x) where x is 0 or x % page_size == 0. >>> In the former it is the same case as alloca(0) while the latter is >>> safe because any allocation pushes the outgoing stack args down: >>> >>>|FP | >>>+---+ >>>| | >>>|dynamic allocations| alloca (x) >>>| | >>>+---+ >>>|padding| >>>+---+ >>>|outgoing stack args| safety buffer of 8 bytes (aligned) >>>+---+ >>> >>> Which means when you probe for the residual, if it's 0 you'll again >>> just probe in the outgoing stack args range, which we know is non-zero (at >> least 8 byte
RE: [PATCH][GCC][AArch64] Ensure that outgoing argument size is at least 8 bytes when alloca and stack-clash. [Patch (3/6)]
Hi All, Attached an updated patch which documents what the test cases are expecting as requested. Ok for trunk? Thanks, Tamar gcc/ 2018-07-25 Tamar Christina PR target/86486 * config/aarch64/aarch64.h (STACK_CLASH_OUTGOING_ARGS, STACK_DYNAMIC_OFFSET): New. * config/aarch64/aarch64.c (aarch64_layout_frame): Update outgoing args size. (aarch64_stack_clash_protection_alloca_probe_range, TARGET_STACK_CLASH_PROTECTION_ALLOCA_PROBE_RANGE): New. gcc/testsuite/ 2018-07-25 Tamar Christina PR target/86486 * gcc.target/aarch64/stack-check-alloca-1.c: New. * gcc.target/aarch64/stack-check-alloca-10.c: New. * gcc.target/aarch64/stack-check-alloca-2.c: New. * gcc.target/aarch64/stack-check-alloca-3.c: New. * gcc.target/aarch64/stack-check-alloca-4.c: New. * gcc.target/aarch64/stack-check-alloca-5.c: New. * gcc.target/aarch64/stack-check-alloca-6.c: New. * gcc.target/aarch64/stack-check-alloca-7.c: New. * gcc.target/aarch64/stack-check-alloca-8.c: New. * gcc.target/aarch64/stack-check-alloca-9.c: New. * gcc.target/aarch64/stack-check-alloca.h: New. * gcc.target/aarch64/stack-check-14.c: New. * gcc.target/aarch64/stack-check-15.c: New. > -Original Message- > From: Tamar Christina > Sent: Friday, July 13, 2018 17:36 > To: Tamar Christina ; gcc-patches@gcc.gnu.org > Cc: nd ; James Greenhalgh ; > Richard Earnshaw ; Marcus Shawcroft > > Subject: RE: [PATCH][GCC][AArch64] Ensure that outgoing argument size is at > least 8 bytes when alloca and stack-clash. [Patch (3/6)] > > Hi All, > > I'm sending an updated patch which updates a testcase that hits one of our > corner cases. > This is an assembler scan only update in a testcase. > > Regards, > Tamar > > > -Original Message- > > From: Tamar Christina > > Sent: Wednesday, July 11, 2018 12:21 > > To: gcc-patches@gcc.gnu.org > > Cc: nd ; James Greenhalgh ; > > Richard Earnshaw ; Marcus Shawcroft > > > > Subject: [PATCH][GCC][AArch64] Ensure that outgoing argument size is > > at least 8 bytes when alloca and stack-clash. [Patch (3/6)] > > > > Hi All, > > > > This patch adds a requirement that the number of outgoing arguments > > for a function is at least 8 bytes when using stack-clash protection. > > > > By using this condition we can avoid a check in the alloca code and so > > have smaller and simpler code there. > > > > A simplified version of the AArch64 stack frames is: > > > >+---+ > >| | > >| | > >| | > >+---+ > >|LR | > >+---+ > >|FP | > >+---+ > >|dynamic allocations| expanding area which will push the > > outgoing > >+---+ args down during each allocation. > >|padding| > >+---+ > >|outgoing stack args| safety buffer of 8 bytes (aligned) > >+---+ > > > > By always defining an outgoing argument, alloca(0) effectively is safe > > to probe at $sp due to the reserved buffer being there. It will never > > corrupt the stack. > > > > This is also safe for alloca(x) where x is 0 or x % page_size == 0. > > In the former it is the same case as alloca(0) while the latter is > > safe because any allocation pushes the outgoing stack args down: > > > >|FP | > >+---+ > >| | > >|dynamic allocations| alloca (x) > >| | > >+---+ > >|padding| > >+---+ > >|outgoing stack args| safety buffer of 8 bytes (aligned) > >+---+ > > > > Which means when you probe for the residual, if it's 0 you'll again > > just probe in the outgoing stack args range, which we know is non-zero (at > least 8 bytes). > > > > Bootstrapped Regtested on aarch64-none-linux-gnu and no issues. > > Target was tested with stack clash on and off by default. > > > > Ok for trunk? > > > > Thanks, > > Tamar > > > > gcc/ > > 2018-07-11 Tamar Christina > > > > PR target/86486 > > * config/aarch64/aarch64.h (STACK_CLASH_OUTGOING_ARGS, > > STACK_DYNAMIC_OFFSET): New. >
RE: [PATCH][GCC][AArch64] Ensure that outgoing argument size is at least 8 bytes when alloca and stack-clash. [Patch (3/6)]
Hi All, I'm sending an updated patch which updates a testcase that hits one of our corner cases. This is an assembler scan only update in a testcase. Regards, Tamar > -Original Message- > From: Tamar Christina > Sent: Wednesday, July 11, 2018 12:21 > To: gcc-patches@gcc.gnu.org > Cc: nd ; James Greenhalgh ; > Richard Earnshaw ; Marcus Shawcroft > > Subject: [PATCH][GCC][AArch64] Ensure that outgoing argument size is at > least 8 bytes when alloca and stack-clash. [Patch (3/6)] > > Hi All, > > This patch adds a requirement that the number of outgoing arguments for a > function is at least 8 bytes when using stack-clash protection. > > By using this condition we can avoid a check in the alloca code and so have > smaller and simpler code there. > > A simplified version of the AArch64 stack frames is: > >+---+ >| | >| | >| | >+---+ >|LR | >+---+ >|FP | >+---+ >|dynamic allocations| expanding area which will push the outgoing >+---+ args down during each allocation. >|padding| >+---+ >|outgoing stack args| safety buffer of 8 bytes (aligned) >+---+ > > By always defining an outgoing argument, alloca(0) effectively is safe to > probe at $sp due to the reserved buffer being there. It will never corrupt > the > stack. > > This is also safe for alloca(x) where x is 0 or x % page_size == 0. In the > former > it is the same case as alloca(0) while the latter is safe because any > allocation > pushes the outgoing stack args down: > >|FP | >+---+ >| | >|dynamic allocations| alloca (x) >| | >+---+ >|padding| >+---+ >|outgoing stack args| safety buffer of 8 bytes (aligned) >+---+ > > Which means when you probe for the residual, if it's 0 you'll again just probe > in the outgoing stack args range, which we know is non-zero (at least 8 > bytes). > > Bootstrapped Regtested on aarch64-none-linux-gnu and no issues. > Target was tested with stack clash on and off by default. > > Ok for trunk? > > Thanks, > Tamar > > gcc/ > 2018-07-11 Tamar Christina > > PR target/86486 > * config/aarch64/aarch64.h (STACK_CLASH_OUTGOING_ARGS, > STACK_DYNAMIC_OFFSET): New. > * config/aarch64/aarch64.c (aarch64_layout_frame): > Update outgoing args size. > (aarch64_stack_clash_protection_alloca_probe_range, > TARGET_STACK_CLASH_PROTECTION_ALLOCA_PROBE_RANGE): > New. > > gcc/testsuite/ > 2018-07-11 Tamar Christina > > PR target/86486 > * gcc.target/aarch64/stack-check-alloca-1.c: New. > * gcc.target/aarch64/stack-check-alloca-10.c: New. > * gcc.target/aarch64/stack-check-alloca-2.c: New. > * gcc.target/aarch64/stack-check-alloca-3.c: New. > * gcc.target/aarch64/stack-check-alloca-4.c: New. > * gcc.target/aarch64/stack-check-alloca-5.c: New. > * gcc.target/aarch64/stack-check-alloca-6.c: New. > * gcc.target/aarch64/stack-check-alloca-7.c: New. > * gcc.target/aarch64/stack-check-alloca-8.c: New. > * gcc.target/aarch64/stack-check-alloca-9.c: New. > * gcc.target/aarch64/stack-check-alloca.h: New. > * gcc.target/aarch64/stack-check-14.c: New. > * gcc.target/aarch64/stack-check-15.c: New. > > -- diff --git a/gcc/config/aarch64/aarch64.h b/gcc/config/aarch64/aarch64.h index 1345f0eb171d05e2b833935c0a32f79c3db03f99..e9560b53bd8b5761855561dbf82d9c90cc1c282a 100644 --- a/gcc/config/aarch64/aarch64.h +++ b/gcc/config/aarch64/aarch64.h @@ -88,6 +88,10 @@ before probing has to be done for stack clash protection. */ #define STACK_CLASH_CALLER_GUARD 1024 +/* This value represents the minimum amount of bytes we expect the function's + outgoing arguments to be when stack-clash is enabled. */ +#define STACK_CLASH_OUTGOING_ARGS 8 + /* This value controls how many pages we manually unroll the loop for when generating stack clash probes. */ #define STACK_CLASH_MAX_UNROLL_PAGES 4 @@ -1069,4 +1073,15 @@ extern poly_uint16 aarch64_sve_vg; #define REGMODE_NATURAL_SIZE(MODE) aarch64_regmode_natural_size (MODE) +/* Allocate the minimum of STACK_CLASH_OUTGOING_ARGS if stack clash protection + is enabled for the outgoi
[PATCH][GCC][AArch64] Ensure that outgoing argument size is at least 8 bytes when alloca and stack-clash. [Patch (3/6)]
Hi All, This patch adds a requirement that the number of outgoing arguments for a function is at least 8 bytes when using stack-clash protection. By using this condition we can avoid a check in the alloca code and so have smaller and simpler code there. A simplified version of the AArch64 stack frames is: +---+ | | | | | | +---+ |LR | +---+ |FP | +---+ |dynamic allocations| expanding area which will push the outgoing +---+ args down during each allocation. |padding| +---+ |outgoing stack args| safety buffer of 8 bytes (aligned) +---+ By always defining an outgoing argument, alloca(0) effectively is safe to probe at $sp due to the reserved buffer being there. It will never corrupt the stack. This is also safe for alloca(x) where x is 0 or x % page_size == 0. In the former it is the same case as alloca(0) while the latter is safe because any allocation pushes the outgoing stack args down: |FP | +---+ | | |dynamic allocations| alloca (x) | | +---+ |padding| +---+ |outgoing stack args| safety buffer of 8 bytes (aligned) +---+ Which means when you probe for the residual, if it's 0 you'll again just probe in the outgoing stack args range, which we know is non-zero (at least 8 bytes). Bootstrapped Regtested on aarch64-none-linux-gnu and no issues. Target was tested with stack clash on and off by default. Ok for trunk? Thanks, Tamar gcc/ 2018-07-11 Tamar Christina PR target/86486 * config/aarch64/aarch64.h (STACK_CLASH_OUTGOING_ARGS, STACK_DYNAMIC_OFFSET): New. * config/aarch64/aarch64.c (aarch64_layout_frame): Update outgoing args size. (aarch64_stack_clash_protection_alloca_probe_range, TARGET_STACK_CLASH_PROTECTION_ALLOCA_PROBE_RANGE): New. gcc/testsuite/ 2018-07-11 Tamar Christina PR target/86486 * gcc.target/aarch64/stack-check-alloca-1.c: New. * gcc.target/aarch64/stack-check-alloca-10.c: New. * gcc.target/aarch64/stack-check-alloca-2.c: New. * gcc.target/aarch64/stack-check-alloca-3.c: New. * gcc.target/aarch64/stack-check-alloca-4.c: New. * gcc.target/aarch64/stack-check-alloca-5.c: New. * gcc.target/aarch64/stack-check-alloca-6.c: New. * gcc.target/aarch64/stack-check-alloca-7.c: New. * gcc.target/aarch64/stack-check-alloca-8.c: New. * gcc.target/aarch64/stack-check-alloca-9.c: New. * gcc.target/aarch64/stack-check-alloca.h: New. * gcc.target/aarch64/stack-check-14.c: New. * gcc.target/aarch64/stack-check-15.c: New. -- diff --git a/gcc/config/aarch64/aarch64.h b/gcc/config/aarch64/aarch64.h index 1345f0eb171d05e2b833935c0a32f79c3db03f99..e9560b53bd8b5761855561dbf82d9c90cc1c282a 100644 --- a/gcc/config/aarch64/aarch64.h +++ b/gcc/config/aarch64/aarch64.h @@ -88,6 +88,10 @@ before probing has to be done for stack clash protection. */ #define STACK_CLASH_CALLER_GUARD 1024 +/* This value represents the minimum amount of bytes we expect the function's + outgoing arguments to be when stack-clash is enabled. */ +#define STACK_CLASH_OUTGOING_ARGS 8 + /* This value controls how many pages we manually unroll the loop for when generating stack clash probes. */ #define STACK_CLASH_MAX_UNROLL_PAGES 4 @@ -1069,4 +1073,15 @@ extern poly_uint16 aarch64_sve_vg; #define REGMODE_NATURAL_SIZE(MODE) aarch64_regmode_natural_size (MODE) +/* Allocate the minimum of STACK_CLASH_OUTGOING_ARGS if stack clash protection + is enabled for the outgoing arguments. This is essential as the extra args + space allows if to skip a check in alloca. */ +#undef STACK_DYNAMIC_OFFSET +#define STACK_DYNAMIC_OFFSET(FUNDECL) \ + ((flag_stack_clash_protection \ + && cfun->calls_alloca \ + && known_lt (crtl->outgoing_args_size, STACK_CLASH_OUTGOING_ARGS))\ +? ROUND_UP (STACK_CLASH_OUTGOING_ARGS, STACK_BOUNDARY / BITS_PER_UNIT) \ +: (crtl->outgoing_args_size +
