hardcfr: make builtin_return tests more portable [PR112334]

  Rework __builtin_return tests to explicitly call __builtin_apply and
use its return value rather than anything else.  Also require
untyped_assembly.  Avoid the noise out of exceptions escaping the
builtin-applied function, but add a test to cover their effects as
well.

Regstrapped on x86_64-linux-gnu.  Also tested on arm-eabi, but it's
*not* enough (or needed) to fix the PR, there's another bug lurking
there, with a separate patch coming up.  Regardless, is this ok to
install?


for  gcc/testsuite/ChangeLog

	PR target/112334
	* c-c++-common/torture/harden-cfr-bret.c: Rework for stricter
	untyped_return requirements.  Require untyped_assembly.
	* c-c++-common/torture/harden-cfr-bret-except.c: New.
	* c-c++-common/torture/harden-cfr-bret-always.c: Require
	untyped_assembly.
	* c-c++-common/torture/harden-cfr-bret-never.c: Likewise.
	* c-c++-common/torture/harden-cfr-bret-noopt.c: Likewise.
	* c-c++-common/torture/harden-cfr-bret-noret.c: Likewise.
	* c-c++-common/torture/harden-cfr-bret-no-xthrow.c: Likewise.
	* c-c++-common/torture/harden-cfr-bret-nothrow.c: Likewise.
	* c-c++-common/torture/harden-cfr-bret-retcl.c: Likewise.
---
 .../c-c++-common/torture/harden-cfr-bret-always.c  |    3 ++-
 .../c-c++-common/torture/harden-cfr-bret-except.c  |   17 +++++++++++++++
 .../c-c++-common/torture/harden-cfr-bret-never.c   |    3 ++-
 .../torture/harden-cfr-bret-no-xthrow.c            |    3 ++-
 .../c-c++-common/torture/harden-cfr-bret-noopt.c   |    3 ++-
 .../c-c++-common/torture/harden-cfr-bret-noret.c   |    3 ++-
 .../c-c++-common/torture/harden-cfr-bret-nothrow.c |    3 ++-
 .../c-c++-common/torture/harden-cfr-bret-retcl.c   |    3 ++-
 .../c-c++-common/torture/harden-cfr-bret.c         |   23 ++++++++++++++++----
 .../c-c++-common/torture/harden-cfr-noret.c        |    2 +-
 10 files changed, 50 insertions(+), 13 deletions(-)
 create mode 100644 gcc/testsuite/c-c++-common/torture/harden-cfr-bret-except.c
  

On Fri, Dec 1, 2023 at 1:58 PM Alexandre Oliva <oliva@adacore.com> wrote:
>
>
> Rework __builtin_return tests to explicitly call __builtin_apply and
> use its return value rather than anything else.  Also require
> untyped_assembly.  Avoid the noise out of exceptions escaping the
> builtin-applied function, but add a test to cover their effects as
> well.
>
> Regstrapped on x86_64-linux-gnu.  Also tested on arm-eabi, but it's
> *not* enough (or needed) to fix the PR, there's another bug lurking
> there, with a separate patch coming up.  Regardless, is this ok to
> install?

OK.

>
> for  gcc/testsuite/ChangeLog
>
>         PR target/112334
>         * c-c++-common/torture/harden-cfr-bret.c: Rework for stricter
>         untyped_return requirements.  Require untyped_assembly.
>         * c-c++-common/torture/harden-cfr-bret-except.c: New.
>         * c-c++-common/torture/harden-cfr-bret-always.c: Require
>         untyped_assembly.
>         * c-c++-common/torture/harden-cfr-bret-never.c: Likewise.
>         * c-c++-common/torture/harden-cfr-bret-noopt.c: Likewise.
>         * c-c++-common/torture/harden-cfr-bret-noret.c: Likewise.
>         * c-c++-common/torture/harden-cfr-bret-no-xthrow.c: Likewise.
>         * c-c++-common/torture/harden-cfr-bret-nothrow.c: Likewise.
>         * c-c++-common/torture/harden-cfr-bret-retcl.c: Likewise.
> ---
>  .../c-c++-common/torture/harden-cfr-bret-always.c  |    3 ++-
>  .../c-c++-common/torture/harden-cfr-bret-except.c  |   17 +++++++++++++++
>  .../c-c++-common/torture/harden-cfr-bret-never.c   |    3 ++-
>  .../torture/harden-cfr-bret-no-xthrow.c            |    3 ++-
>  .../c-c++-common/torture/harden-cfr-bret-noopt.c   |    3 ++-
>  .../c-c++-common/torture/harden-cfr-bret-noret.c   |    3 ++-
>  .../c-c++-common/torture/harden-cfr-bret-nothrow.c |    3 ++-
>  .../c-c++-common/torture/harden-cfr-bret-retcl.c   |    3 ++-
>  .../c-c++-common/torture/harden-cfr-bret.c         |   23 ++++++++++++++++----
>  .../c-c++-common/torture/harden-cfr-noret.c        |    2 +-
>  10 files changed, 50 insertions(+), 13 deletions(-)
>  create mode 100644 gcc/testsuite/c-c++-common/torture/harden-cfr-bret-except.c
>
> diff --git a/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-always.c b/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-always.c
> index 779896c60e846..3406c4e6ef9dc 100644
> --- a/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-always.c
> +++ b/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-always.c
> @@ -1,5 +1,6 @@
>  /* { dg-do compile } */
> -/* { dg-options "-fharden-control-flow-redundancy -fhardcfr-check-noreturn-calls=always -fdump-tree-hardcfr -ffat-lto-objects" } */
> +/* { dg-options "-fharden-control-flow-redundancy -fhardcfr-check-noreturn-calls=always -fno-exceptions -fdump-tree-hardcfr -ffat-lto-objects" } */
> +/* { dg-require-effective-target untyped_assembly } */
>
>  /* Check that, even enabling all checks before noreturn calls (leaving
>     returning calls enabled), we get checks before __builtin_return without
> diff --git a/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-except.c b/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-except.c
> new file mode 100644
> index 0000000000000..3acb61cb75a77
> --- /dev/null
> +++ b/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-except.c
> @@ -0,0 +1,17 @@
> +/* { dg-do compile } */
> +/* { dg-options "-fharden-control-flow-redundancy -fexceptions -fdump-tree-hardcfr -ffat-lto-objects" } */
> +/* { dg-require-effective-target untyped_assembly } */
> +
> +/* Check that, with exceptions enabled, even in C, the calls initiated by
> +   builtin_apply are enclosed in cleanup handlers that add extra checks.
> +   Unfortunately, declaring foobar as nothrow is not enough to avoid the
> +   handler around the builtin_apply call, so the other bret tests all use
> +   -fno-exceptions.  */
> +
> +#include "harden-cfr-bret.c"
> +
> +/* With exceptions, we get an extra check per function, to check before
> +   propagating exceptions, so it's 3 in f and 2 in g.  */
> +/* { dg-final { scan-tree-dump-times "__hardcfr_check" 5 "hardcfr" } } */
> +/* The extra check in g also removes the possibility of inlining the check.  */
> +/* { dg-final { scan-tree-dump-times "__builtin_trap" 0 "hardcfr" } } */
> diff --git a/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-never.c b/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-never.c
> index 49ce17f5b937c..7f8fb64138df1 100644
> --- a/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-never.c
> +++ b/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-never.c
> @@ -1,5 +1,6 @@
>  /* { dg-do compile } */
> -/* { dg-options "-fharden-control-flow-redundancy -fhardcfr-check-noreturn-calls=never -fdump-tree-hardcfr -ffat-lto-objects" } */
> +/* { dg-options "-fharden-control-flow-redundancy -fhardcfr-check-noreturn-calls=never -fno-exceptions -fdump-tree-hardcfr -ffat-lto-objects" } */
> +/* { dg-require-effective-target untyped_assembly } */
>
>  /* Check that, even enabling checks before never noreturn calls (leaving
>     returning calls enabled), we get checks before __builtin_return without
> diff --git a/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-no-xthrow.c b/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-no-xthrow.c
> index 78e5bf4143927..07588e8d3c341 100644
> --- a/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-no-xthrow.c
> +++ b/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-no-xthrow.c
> @@ -1,5 +1,6 @@
>  /* { dg-do compile } */
> -/* { dg-options "-fharden-control-flow-redundancy -fhardcfr-check-noreturn-calls=no-xthrow -fdump-tree-hardcfr -ffat-lto-objects" } */
> +/* { dg-options "-fharden-control-flow-redundancy -fhardcfr-check-noreturn-calls=no-xthrow -fno-exceptions -fdump-tree-hardcfr -ffat-lto-objects" } */
> +/* { dg-require-effective-target untyped_assembly } */
>
>  /* Check that, even enabling checks before no-xthrow-throwing noreturn calls
>     (leaving returning calls enabled), we get checks before __builtin_return
> diff --git a/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-noopt.c b/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-noopt.c
> index 1512614791ff2..716d9297c8d94 100644
> --- a/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-noopt.c
> +++ b/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-noopt.c
> @@ -1,5 +1,6 @@
>  /* { dg-do compile } */
> -/* { dg-options "-fharden-control-flow-redundancy -fhardcfr-check-noreturn-calls=never -fno-hardcfr-check-returning-calls -fdump-tree-hardcfr -ffat-lto-objects" } */
> +/* { dg-options "-fharden-control-flow-redundancy -fhardcfr-check-noreturn-calls=never -fno-hardcfr-check-returning-calls -fno-exceptions -fdump-tree-hardcfr -ffat-lto-objects" } */
> +/* { dg-require-effective-target untyped_assembly } */
>
>  /* Check that, even disabling checks before both noreturn and returning
>     calls, we still get checks before __builtin_return.  */
> diff --git a/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-noret.c b/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-noret.c
> index fd95bb7e3e334..c6d2baa312031 100644
> --- a/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-noret.c
> +++ b/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-noret.c
> @@ -1,5 +1,6 @@
>  /* { dg-do compile } */
> -/* { dg-options "-fharden-control-flow-redundancy -fno-hardcfr-check-returning-calls -fdump-tree-hardcfr -ffat-lto-objects" } */
> +/* { dg-options "-fharden-control-flow-redundancy -fno-hardcfr-check-returning-calls -fno-exceptions -fdump-tree-hardcfr -ffat-lto-objects" } */
> +/* { dg-require-effective-target untyped_assembly } */
>
>  /* Check that, even disabling checks before returning calls (leaving noreturn
>     calls enabled), we still get checks before __builtin_return.  */
> diff --git a/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-nothrow.c b/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-nothrow.c
> index c5c361234c499..2fd0d82c7ea3e 100644
> --- a/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-nothrow.c
> +++ b/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-nothrow.c
> @@ -1,5 +1,6 @@
>  /* { dg-do compile } */
> -/* { dg-options "-fharden-control-flow-redundancy -fhardcfr-check-noreturn-calls=nothrow -fdump-tree-hardcfr -ffat-lto-objects" } */
> +/* { dg-options "-fharden-control-flow-redundancy -fhardcfr-check-noreturn-calls=nothrow -fno-exceptions -fdump-tree-hardcfr -ffat-lto-objects" } */
> +/* { dg-require-effective-target untyped_assembly } */
>
>  /* Check that, even enabling checks before nothrow noreturn calls (leaving
>     returning calls enabled), we get checks before __builtin_return without
> diff --git a/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-retcl.c b/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-retcl.c
> index 137dfbb95d6bb..b070294fde8ad 100644
> --- a/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-retcl.c
> +++ b/gcc/testsuite/c-c++-common/torture/harden-cfr-bret-retcl.c
> @@ -1,5 +1,6 @@
>  /* { dg-do compile } */
> -/* { dg-options "-fharden-control-flow-redundancy -fhardcfr-check-noreturn-calls=never -fdump-tree-hardcfr -ffat-lto-objects" } */
> +/* { dg-options "-fharden-control-flow-redundancy -fhardcfr-check-noreturn-calls=never -fno-exceptions -fdump-tree-hardcfr -ffat-lto-objects" } */
> +/* { dg-require-effective-target untyped_assembly } */
>
>  /* Check that, even disabling checks before noreturn calls (leaving returning
>     calls enabled), we still get checks before __builtin_return.  */
> diff --git a/gcc/testsuite/c-c++-common/torture/harden-cfr-bret.c b/gcc/testsuite/c-c++-common/torture/harden-cfr-bret.c
> index b459ff6b86491..b6630a6c86695 100644
> --- a/gcc/testsuite/c-c++-common/torture/harden-cfr-bret.c
> +++ b/gcc/testsuite/c-c++-common/torture/harden-cfr-bret.c
> @@ -1,14 +1,27 @@
>  /* { dg-do compile } */
> -/* { dg-options "-fharden-control-flow-redundancy -fdump-tree-hardcfr -ffat-lto-objects" } */
> +/* { dg-options "-fharden-control-flow-redundancy -fno-exceptions -fdump-tree-hardcfr -ffat-lto-objects" } */
> +/* { dg-require-effective-target untyped_assembly } */
>
> -int f(int i) {
> +extern int foobar (void);
> +
> +#if __cplusplus
> +typedef void (*fnt)(...);
> +#else
> +typedef void (*fnt)();
> +#endif
> +
> +int i;
> +
> +int f(void) {
>    if (i)
> -    __builtin_return (&i);
> +    __builtin_return (__builtin_apply ((fnt)foobar,
> +                                      __builtin_apply_args (), 0));
>    return i;
>  }
>
> -int g(int i) {
> -  __builtin_return (&i);
> +int g(void) {
> +  __builtin_return (__builtin_apply ((fnt)foobar,
> +                                    __builtin_apply_args (), 0));
>  }
>
>  /* Out-of-line checking, before both builtin_return and return in f.  */
> diff --git a/gcc/testsuite/c-c++-common/torture/harden-cfr-noret.c b/gcc/testsuite/c-c++-common/torture/harden-cfr-noret.c
> index fdd803109a4ae..8c7cc01c0ce68 100644
> --- a/gcc/testsuite/c-c++-common/torture/harden-cfr-noret.c
> +++ b/gcc/testsuite/c-c++-common/torture/harden-cfr-noret.c
> @@ -1,5 +1,5 @@
>  /* { dg-do compile } */
> -/* { dg-options "-fharden-control-flow-redundancy -fhardcfr-check-noreturn-calls=always -fdump-tree-hardcfr -ffat-lto-objects" } */
> +/* { dg-options "-fharden-control-flow-redundancy -fhardcfr-check-noreturn-calls=always -fno-exceptions -fdump-tree-hardcfr -ffat-lto-objects" } */
>
>  /* Check that we insert checking before all noreturn calls.  */
>
>
> --
> Alexandre Oliva, happy hacker            https://FSFLA.org/blogs/lxo/
>    Free Software Activist                   GNU Toolchain Engineer
> More tolerance and less prejudice are key for inclusion and diversity
> Excluding neuro-others for not behaving ""normal"" is *not* inclusive
  

On Dec  1, 2023, Alexandre Oliva <oliva@adacore.com> wrote:

> diff --git a/gcc/testsuite/c-c++-common/torture/harden-cfr-noret.c b/gcc/testsuite/c-c++-common/torture/harden-cfr-noret.c
> index fdd803109a4ae..8c7cc01c0ce68 100644
> --- a/gcc/testsuite/c-c++-common/torture/harden-cfr-noret.c
> +++ b/gcc/testsuite/c-c++-common/torture/harden-cfr-noret.c
> @@ -1,5 +1,5 @@
>  /* { dg-do compile } */
> -/* { dg-options "-fharden-control-flow-redundancy -fhardcfr-check-noreturn-calls=always -fdump-tree-hardcfr -ffat-lto-objects" } */
> +/* { dg-options "-fharden-control-flow-redundancy -fhardcfr-check-noreturn-calls=always -fno-exceptions -fdump-tree-hardcfr -ffat-lto-objects" } */

This one was *not* meant to be modified, it was changed by accident in
my tree and integrated by mistake with the posted patch.  Fortunately
the ChangeLog verifier caught the mistake, and I dropped it from the
patch I've just pushed.