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[1/1] testsuite/arm: Add arm_cmse_hw effective target

Message ID 1618824971-9225-1-git-send-email-christophe.lyon@linaro.org
State New
Headers show
Series [1/1] testsuite/arm: Add arm_cmse_hw effective target | expand

Commit Message

Christophe Lyon April 19, 2021, 9:36 a.m. UTC
Some of the CMSE tests have 'dg-do run', but qemu-arm does not support
the privileged instructions involved; one has to use qemu-system-arm
for this, which in turn requires modifications to the default
newlib/libgloss startup code to enable the FPU as the FP status
registers need to be saved when using CMSE code.

This patch introduces arm_cmse_hw, similar to arm_neon_hw, to detect
whether the execution engine supports the CMSE instructions. If not,
we set dg-do-what-default to assemble instead of run. We thus remove
all the 'dg-do run' directives from CMSE tests, to rely on
dg-do-what-default instead.

Note that cmse-16.c used to pass with dg-do run under qemu-arm,
because the property being tested is not available (qemu-arm does not
model secure vs non-secure memory). The patch removes dg-do from it
too, since it is relevant only with an adequate simulator.

Before the patch, bitfield-[123].c and struct-1.c fail at execution
under qemu-arm. With the patch, execution is skipped.

The same tests pass under qemu-system-arm both with and without the
patch.

This avoids failures when testing with
-mthumb/-mfloat-abi=hard/-march=armv8-m.main+fp+dsp under qemu-arm for
cortex-m33.

I'm also running tests with qemu-system-arm for cortex-m33, but I run
only cmse.exp with a patched newlib in this case: I use qemu-arm for
all combinations except that one because it's faster and supports
semihosting.

I do not have a setup to check this with actual hardware or another
simulator.

2021-04-19  Christophe Lyon  <christophe.lyon@linaro.org>

	gcc/
	* doc/sourcebuild.texi (arm_cmse_hw): Document.

	gcc/testsuite/
	* gcc.target/arm/cmse/bitfield-1.c: Remove dg-do.
	* gcc.target/arm/cmse/bitfield-2.c: Likewise.
	* gcc.target/arm/cmse/bitfield-3.c: Likewise.
	* gcc.target/arm/cmse/cmse-16.c: Likewise.
	* gcc.target/arm/cmse/struct-1.c: Likewise.
	* gcc.target/arm/cmse/cmse.exp: Set dg-do-what-default depending
	on arm_cmse_hw.
	* lib/target-supports.exp (check_effective_target_arm_cmse_hw):
	New.
---
 gcc/doc/sourcebuild.texi                       |  3 +++
 gcc/testsuite/gcc.target/arm/cmse/bitfield-1.c |  2 +-
 gcc/testsuite/gcc.target/arm/cmse/bitfield-2.c |  2 +-
 gcc/testsuite/gcc.target/arm/cmse/bitfield-3.c |  2 +-
 gcc/testsuite/gcc.target/arm/cmse/cmse-16.c    |  6 +++++-
 gcc/testsuite/gcc.target/arm/cmse/cmse.exp     |  7 ++++++-
 gcc/testsuite/gcc.target/arm/cmse/struct-1.c   |  2 +-
 gcc/testsuite/lib/target-supports.exp          | 15 +++++++++++++++
 8 files changed, 33 insertions(+), 6 deletions(-)

Comments

Richard Sandiford April 26, 2021, 8:55 a.m. UTC | #1
Christophe Lyon via Gcc-patches <gcc-patches@gcc.gnu.org> writes:
> Some of the CMSE tests have 'dg-do run', but qemu-arm does not support
> the privileged instructions involved; one has to use qemu-system-arm
> for this, which in turn requires modifications to the default
> newlib/libgloss startup code to enable the FPU as the FP status
> registers need to be saved when using CMSE code.
>
> This patch introduces arm_cmse_hw, similar to arm_neon_hw, to detect
> whether the execution engine supports the CMSE instructions. If not,
> we set dg-do-what-default to assemble instead of run. We thus remove
> all the 'dg-do run' directives from CMSE tests, to rely on
> dg-do-what-default instead.
>
> Note that cmse-16.c used to pass with dg-do run under qemu-arm,
> because the property being tested is not available (qemu-arm does not
> model secure vs non-secure memory). The patch removes dg-do from it
> too, since it is relevant only with an adequate simulator.
>
> Before the patch, bitfield-[123].c and struct-1.c fail at execution
> under qemu-arm. With the patch, execution is skipped.
>
> The same tests pass under qemu-system-arm both with and without the
> patch.
>
> This avoids failures when testing with
> -mthumb/-mfloat-abi=hard/-march=armv8-m.main+fp+dsp under qemu-arm for
> cortex-m33.
>
> I'm also running tests with qemu-system-arm for cortex-m33, but I run
> only cmse.exp with a patched newlib in this case: I use qemu-arm for
> all combinations except that one because it's faster and supports
> semihosting.
>
> I do not have a setup to check this with actual hardware or another
> simulator.
>
> 2021-04-19  Christophe Lyon  <christophe.lyon@linaro.org>
>
> 	gcc/
> 	* doc/sourcebuild.texi (arm_cmse_hw): Document.
>
> 	gcc/testsuite/
> 	* gcc.target/arm/cmse/bitfield-1.c: Remove dg-do.
> 	* gcc.target/arm/cmse/bitfield-2.c: Likewise.
> 	* gcc.target/arm/cmse/bitfield-3.c: Likewise.
> 	* gcc.target/arm/cmse/cmse-16.c: Likewise.
> 	* gcc.target/arm/cmse/struct-1.c: Likewise.
> 	* gcc.target/arm/cmse/cmse.exp: Set dg-do-what-default depending
> 	on arm_cmse_hw.
> 	* lib/target-supports.exp (check_effective_target_arm_cmse_hw):
> 	New.

OK, thanks.

It feels to me like we're hard-coding the magic rune
-Wl,--section-start,.gnu.sgstubs=0x00400000 in too many places,
but that's pre-existing.

Richard

> ---
>  gcc/doc/sourcebuild.texi                       |  3 +++
>  gcc/testsuite/gcc.target/arm/cmse/bitfield-1.c |  2 +-
>  gcc/testsuite/gcc.target/arm/cmse/bitfield-2.c |  2 +-
>  gcc/testsuite/gcc.target/arm/cmse/bitfield-3.c |  2 +-
>  gcc/testsuite/gcc.target/arm/cmse/cmse-16.c    |  6 +++++-
>  gcc/testsuite/gcc.target/arm/cmse/cmse.exp     |  7 ++++++-
>  gcc/testsuite/gcc.target/arm/cmse/struct-1.c   |  2 +-
>  gcc/testsuite/lib/target-supports.exp          | 15 +++++++++++++++
>  8 files changed, 33 insertions(+), 6 deletions(-)
>
> diff --git a/gcc/doc/sourcebuild.texi b/gcc/doc/sourcebuild.texi
> index 0104916..616a267 100644
> --- a/gcc/doc/sourcebuild.texi
> +++ b/gcc/doc/sourcebuild.texi
> @@ -2012,6 +2012,9 @@ div instruction.
>  ARM target supports ARMv8-M Security Extensions, enabled by the @code{-mcmse}
>  option.
>  
> +@item arm_cmse_hw
> +Test system supports executing CMSE instructions.
> +
>  @item arm_coproc1_ok
>  @anchor{arm_coproc1_ok}
>  ARM target supports the following coprocessor instructions: @code{CDP},
> diff --git a/gcc/testsuite/gcc.target/arm/cmse/bitfield-1.c b/gcc/testsuite/gcc.target/arm/cmse/bitfield-1.c
> index cae2f06..5685f74 100644
> --- a/gcc/testsuite/gcc.target/arm/cmse/bitfield-1.c
> +++ b/gcc/testsuite/gcc.target/arm/cmse/bitfield-1.c
> @@ -1,4 +1,4 @@
> -/* { dg-do run } */
> +/* This test is executed only if the execution engine supports CMSE instructions.  */
>  /* { dg-options "--save-temps -mcmse -Wl,--section-start,.gnu.sgstubs=0x00400000" } */
>  
>  typedef struct
> diff --git a/gcc/testsuite/gcc.target/arm/cmse/bitfield-2.c b/gcc/testsuite/gcc.target/arm/cmse/bitfield-2.c
> index 21a53cd..7a794d4 100644
> --- a/gcc/testsuite/gcc.target/arm/cmse/bitfield-2.c
> +++ b/gcc/testsuite/gcc.target/arm/cmse/bitfield-2.c
> @@ -1,4 +1,4 @@
> -/* { dg-do run } */
> +/* This test is executed only if the execution engine supports CMSE instructions.  */
>  /* { dg-options "--save-temps -mcmse -Wl,--section-start,.gnu.sgstubs=0x00400000" } */
>  
>  typedef struct
> diff --git a/gcc/testsuite/gcc.target/arm/cmse/bitfield-3.c b/gcc/testsuite/gcc.target/arm/cmse/bitfield-3.c
> index e8f973e..5875f8df 100644
> --- a/gcc/testsuite/gcc.target/arm/cmse/bitfield-3.c
> +++ b/gcc/testsuite/gcc.target/arm/cmse/bitfield-3.c
> @@ -1,4 +1,4 @@
> -/* { dg-do run } */
> +/* This test is executed only if the execution engine supports CMSE instructions.  */
>  /* { dg-options "--save-temps -mcmse -Wl,--section-start,.gnu.sgstubs=0x00400000" } */
>  
>  typedef struct
> diff --git a/gcc/testsuite/gcc.target/arm/cmse/cmse-16.c b/gcc/testsuite/gcc.target/arm/cmse/cmse-16.c
> index 3fb0380..6a243d5 100644
> --- a/gcc/testsuite/gcc.target/arm/cmse/cmse-16.c
> +++ b/gcc/testsuite/gcc.target/arm/cmse/cmse-16.c
> @@ -1,4 +1,8 @@
> -/* { dg-do run } */
> +/* This test is executed only if the execution engine supports CMSE instructions.  */
> +/* Note that it "passes" on qemu-arm while it shouldn't because that simulator
> +   does not model secure memory: it's better to skip it in this case, and rely
> +   on do-what-default as set in cmse.exp. (It works as expected with
> +   qemu-system-mode).  */
>  /* { dg-options "-Os -mcmse" }  */
>  
>  #include <arm_cmse.h>
> diff --git a/gcc/testsuite/gcc.target/arm/cmse/cmse.exp b/gcc/testsuite/gcc.target/arm/cmse/cmse.exp
> index 6ce99fe..4da1a46 100644
> --- a/gcc/testsuite/gcc.target/arm/cmse/cmse.exp
> +++ b/gcc/testsuite/gcc.target/arm/cmse/cmse.exp
> @@ -34,7 +34,12 @@ if ![info exists DEFAULT_CFLAGS] then {
>  dg-init
>  
>  set saved-dg-do-what-default ${dg-do-what-default}
> -set dg-do-what-default "assemble"
> +
> +if {[is-effective-target arm_cmse_hw]} then {
> +    set dg-do-what-default run
> +} else {
> +    set dg-do-what-default assemble
> +}
>  
>  set saved-lto_torture_options ${LTO_TORTURE_OPTIONS}
>  set LTO_TORTURE_OPTIONS ""
> diff --git a/gcc/testsuite/gcc.target/arm/cmse/struct-1.c b/gcc/testsuite/gcc.target/arm/cmse/struct-1.c
> index 7555643..75a99f4 100644
> --- a/gcc/testsuite/gcc.target/arm/cmse/struct-1.c
> +++ b/gcc/testsuite/gcc.target/arm/cmse/struct-1.c
> @@ -1,4 +1,4 @@
> -/* { dg-do run } */
> +/* This test is executed only if the execution engine supports CMSE instructions.  */
>  /* { dg-options "--save-temps -mcmse -Wl,--section-start,.gnu.sgstubs=0x00400000" } */
>  
>  typedef struct
> diff --git a/gcc/testsuite/lib/target-supports.exp b/gcc/testsuite/lib/target-supports.exp
> index 1230d19..9b38b41 100644
> --- a/gcc/testsuite/lib/target-supports.exp
> +++ b/gcc/testsuite/lib/target-supports.exp
> @@ -4861,6 +4861,21 @@ proc check_effective_target_arm_cmse_ok {} {
>      } "-mcmse"];
>  }
>  
> +# Return 1 if the target supports executing CMSE instructions, 0
> +# otherwise.  Cache the result.
> +
> +proc check_effective_target_arm_cmse_hw { } {
> +    return [check_runtime arm_cmse_hw_available {
> +	int __attribute__ ((cmse_nonsecure_entry)) ns_func(void)
> +	{
> +	    return 0;
> +	}
> +	int main (void)
> +	{
> +	    return ns_func();
> +	}
> +    } "-mcmse -Wl,--section-start,.gnu.sgstubs=0x00400000"]
> +}
>  # Return 1 if the target supports executing MVE instructions, 0
>  # otherwise.
Christophe Lyon April 26, 2021, 11:22 a.m. UTC | #2
On Mon, 26 Apr 2021 at 10:55, Richard Sandiford
<richard.sandiford@arm.com> wrote:
>
> Christophe Lyon via Gcc-patches <gcc-patches@gcc.gnu.org> writes:
> > Some of the CMSE tests have 'dg-do run', but qemu-arm does not support
> > the privileged instructions involved; one has to use qemu-system-arm
> > for this, which in turn requires modifications to the default
> > newlib/libgloss startup code to enable the FPU as the FP status
> > registers need to be saved when using CMSE code.
> >
> > This patch introduces arm_cmse_hw, similar to arm_neon_hw, to detect
> > whether the execution engine supports the CMSE instructions. If not,
> > we set dg-do-what-default to assemble instead of run. We thus remove
> > all the 'dg-do run' directives from CMSE tests, to rely on
> > dg-do-what-default instead.
> >
> > Note that cmse-16.c used to pass with dg-do run under qemu-arm,
> > because the property being tested is not available (qemu-arm does not
> > model secure vs non-secure memory). The patch removes dg-do from it
> > too, since it is relevant only with an adequate simulator.
> >
> > Before the patch, bitfield-[123].c and struct-1.c fail at execution
> > under qemu-arm. With the patch, execution is skipped.
> >
> > The same tests pass under qemu-system-arm both with and without the
> > patch.
> >
> > This avoids failures when testing with
> > -mthumb/-mfloat-abi=hard/-march=armv8-m.main+fp+dsp under qemu-arm for
> > cortex-m33.
> >
> > I'm also running tests with qemu-system-arm for cortex-m33, but I run
> > only cmse.exp with a patched newlib in this case: I use qemu-arm for
> > all combinations except that one because it's faster and supports
> > semihosting.
> >
> > I do not have a setup to check this with actual hardware or another
> > simulator.
> >
> > 2021-04-19  Christophe Lyon  <christophe.lyon@linaro.org>
> >
> >       gcc/
> >       * doc/sourcebuild.texi (arm_cmse_hw): Document.
> >
> >       gcc/testsuite/
> >       * gcc.target/arm/cmse/bitfield-1.c: Remove dg-do.
> >       * gcc.target/arm/cmse/bitfield-2.c: Likewise.
> >       * gcc.target/arm/cmse/bitfield-3.c: Likewise.
> >       * gcc.target/arm/cmse/cmse-16.c: Likewise.
> >       * gcc.target/arm/cmse/struct-1.c: Likewise.
> >       * gcc.target/arm/cmse/cmse.exp: Set dg-do-what-default depending
> >       on arm_cmse_hw.
> >       * lib/target-supports.exp (check_effective_target_arm_cmse_hw):
> >       New.
>
> OK, thanks.
>
> It feels to me like we're hard-coding the magic rune
> -Wl,--section-start,.gnu.sgstubs=0x00400000 in too many places,
> but that's pre-existing.

Yeah, it did change that address in commit
b61184875ec454875b5a47f3bfa94a6d45f5b845,
but it was already hardcoded before.
(see https://gcc.gnu.org/pipermail/gcc-patches/2019-July/525063.html)

Thanks,

Christophe

>
> Richard
>
> > ---
> >  gcc/doc/sourcebuild.texi                       |  3 +++
> >  gcc/testsuite/gcc.target/arm/cmse/bitfield-1.c |  2 +-
> >  gcc/testsuite/gcc.target/arm/cmse/bitfield-2.c |  2 +-
> >  gcc/testsuite/gcc.target/arm/cmse/bitfield-3.c |  2 +-
> >  gcc/testsuite/gcc.target/arm/cmse/cmse-16.c    |  6 +++++-
> >  gcc/testsuite/gcc.target/arm/cmse/cmse.exp     |  7 ++++++-
> >  gcc/testsuite/gcc.target/arm/cmse/struct-1.c   |  2 +-
> >  gcc/testsuite/lib/target-supports.exp          | 15 +++++++++++++++
> >  8 files changed, 33 insertions(+), 6 deletions(-)
> >
> > diff --git a/gcc/doc/sourcebuild.texi b/gcc/doc/sourcebuild.texi
> > index 0104916..616a267 100644
> > --- a/gcc/doc/sourcebuild.texi
> > +++ b/gcc/doc/sourcebuild.texi
> > @@ -2012,6 +2012,9 @@ div instruction.
> >  ARM target supports ARMv8-M Security Extensions, enabled by the @code{-mcmse}
> >  option.
> >
> > +@item arm_cmse_hw
> > +Test system supports executing CMSE instructions.
> > +
> >  @item arm_coproc1_ok
> >  @anchor{arm_coproc1_ok}
> >  ARM target supports the following coprocessor instructions: @code{CDP},
> > diff --git a/gcc/testsuite/gcc.target/arm/cmse/bitfield-1.c b/gcc/testsuite/gcc.target/arm/cmse/bitfield-1.c
> > index cae2f06..5685f74 100644
> > --- a/gcc/testsuite/gcc.target/arm/cmse/bitfield-1.c
> > +++ b/gcc/testsuite/gcc.target/arm/cmse/bitfield-1.c
> > @@ -1,4 +1,4 @@
> > -/* { dg-do run } */
> > +/* This test is executed only if the execution engine supports CMSE instructions.  */
> >  /* { dg-options "--save-temps -mcmse -Wl,--section-start,.gnu.sgstubs=0x00400000" } */
> >
> >  typedef struct
> > diff --git a/gcc/testsuite/gcc.target/arm/cmse/bitfield-2.c b/gcc/testsuite/gcc.target/arm/cmse/bitfield-2.c
> > index 21a53cd..7a794d4 100644
> > --- a/gcc/testsuite/gcc.target/arm/cmse/bitfield-2.c
> > +++ b/gcc/testsuite/gcc.target/arm/cmse/bitfield-2.c
> > @@ -1,4 +1,4 @@
> > -/* { dg-do run } */
> > +/* This test is executed only if the execution engine supports CMSE instructions.  */
> >  /* { dg-options "--save-temps -mcmse -Wl,--section-start,.gnu.sgstubs=0x00400000" } */
> >
> >  typedef struct
> > diff --git a/gcc/testsuite/gcc.target/arm/cmse/bitfield-3.c b/gcc/testsuite/gcc.target/arm/cmse/bitfield-3.c
> > index e8f973e..5875f8df 100644
> > --- a/gcc/testsuite/gcc.target/arm/cmse/bitfield-3.c
> > +++ b/gcc/testsuite/gcc.target/arm/cmse/bitfield-3.c
> > @@ -1,4 +1,4 @@
> > -/* { dg-do run } */
> > +/* This test is executed only if the execution engine supports CMSE instructions.  */
> >  /* { dg-options "--save-temps -mcmse -Wl,--section-start,.gnu.sgstubs=0x00400000" } */
> >
> >  typedef struct
> > diff --git a/gcc/testsuite/gcc.target/arm/cmse/cmse-16.c b/gcc/testsuite/gcc.target/arm/cmse/cmse-16.c
> > index 3fb0380..6a243d5 100644
> > --- a/gcc/testsuite/gcc.target/arm/cmse/cmse-16.c
> > +++ b/gcc/testsuite/gcc.target/arm/cmse/cmse-16.c
> > @@ -1,4 +1,8 @@
> > -/* { dg-do run } */
> > +/* This test is executed only if the execution engine supports CMSE instructions.  */
> > +/* Note that it "passes" on qemu-arm while it shouldn't because that simulator
> > +   does not model secure memory: it's better to skip it in this case, and rely
> > +   on do-what-default as set in cmse.exp. (It works as expected with
> > +   qemu-system-mode).  */
> >  /* { dg-options "-Os -mcmse" }  */
> >
> >  #include <arm_cmse.h>
> > diff --git a/gcc/testsuite/gcc.target/arm/cmse/cmse.exp b/gcc/testsuite/gcc.target/arm/cmse/cmse.exp
> > index 6ce99fe..4da1a46 100644
> > --- a/gcc/testsuite/gcc.target/arm/cmse/cmse.exp
> > +++ b/gcc/testsuite/gcc.target/arm/cmse/cmse.exp
> > @@ -34,7 +34,12 @@ if ![info exists DEFAULT_CFLAGS] then {
> >  dg-init
> >
> >  set saved-dg-do-what-default ${dg-do-what-default}
> > -set dg-do-what-default "assemble"
> > +
> > +if {[is-effective-target arm_cmse_hw]} then {
> > +    set dg-do-what-default run
> > +} else {
> > +    set dg-do-what-default assemble
> > +}
> >
> >  set saved-lto_torture_options ${LTO_TORTURE_OPTIONS}
> >  set LTO_TORTURE_OPTIONS ""
> > diff --git a/gcc/testsuite/gcc.target/arm/cmse/struct-1.c b/gcc/testsuite/gcc.target/arm/cmse/struct-1.c
> > index 7555643..75a99f4 100644
> > --- a/gcc/testsuite/gcc.target/arm/cmse/struct-1.c
> > +++ b/gcc/testsuite/gcc.target/arm/cmse/struct-1.c
> > @@ -1,4 +1,4 @@
> > -/* { dg-do run } */
> > +/* This test is executed only if the execution engine supports CMSE instructions.  */
> >  /* { dg-options "--save-temps -mcmse -Wl,--section-start,.gnu.sgstubs=0x00400000" } */
> >
> >  typedef struct
> > diff --git a/gcc/testsuite/lib/target-supports.exp b/gcc/testsuite/lib/target-supports.exp
> > index 1230d19..9b38b41 100644
> > --- a/gcc/testsuite/lib/target-supports.exp
> > +++ b/gcc/testsuite/lib/target-supports.exp
> > @@ -4861,6 +4861,21 @@ proc check_effective_target_arm_cmse_ok {} {
> >      } "-mcmse"];
> >  }
> >
> > +# Return 1 if the target supports executing CMSE instructions, 0
> > +# otherwise.  Cache the result.
> > +
> > +proc check_effective_target_arm_cmse_hw { } {
> > +    return [check_runtime arm_cmse_hw_available {
> > +     int __attribute__ ((cmse_nonsecure_entry)) ns_func(void)
> > +     {
> > +         return 0;
> > +     }
> > +     int main (void)
> > +     {
> > +         return ns_func();
> > +     }
> > +    } "-mcmse -Wl,--section-start,.gnu.sgstubs=0x00400000"]
> > +}
> >  # Return 1 if the target supports executing MVE instructions, 0
> >  # otherwise.
diff mbox series

Patch

diff --git a/gcc/doc/sourcebuild.texi b/gcc/doc/sourcebuild.texi
index 0104916..616a267 100644
--- a/gcc/doc/sourcebuild.texi
+++ b/gcc/doc/sourcebuild.texi
@@ -2012,6 +2012,9 @@  div instruction.
 ARM target supports ARMv8-M Security Extensions, enabled by the @code{-mcmse}
 option.
 
+@item arm_cmse_hw
+Test system supports executing CMSE instructions.
+
 @item arm_coproc1_ok
 @anchor{arm_coproc1_ok}
 ARM target supports the following coprocessor instructions: @code{CDP},
diff --git a/gcc/testsuite/gcc.target/arm/cmse/bitfield-1.c b/gcc/testsuite/gcc.target/arm/cmse/bitfield-1.c
index cae2f06..5685f74 100644
--- a/gcc/testsuite/gcc.target/arm/cmse/bitfield-1.c
+++ b/gcc/testsuite/gcc.target/arm/cmse/bitfield-1.c
@@ -1,4 +1,4 @@ 
-/* { dg-do run } */
+/* This test is executed only if the execution engine supports CMSE instructions.  */
 /* { dg-options "--save-temps -mcmse -Wl,--section-start,.gnu.sgstubs=0x00400000" } */
 
 typedef struct
diff --git a/gcc/testsuite/gcc.target/arm/cmse/bitfield-2.c b/gcc/testsuite/gcc.target/arm/cmse/bitfield-2.c
index 21a53cd..7a794d4 100644
--- a/gcc/testsuite/gcc.target/arm/cmse/bitfield-2.c
+++ b/gcc/testsuite/gcc.target/arm/cmse/bitfield-2.c
@@ -1,4 +1,4 @@ 
-/* { dg-do run } */
+/* This test is executed only if the execution engine supports CMSE instructions.  */
 /* { dg-options "--save-temps -mcmse -Wl,--section-start,.gnu.sgstubs=0x00400000" } */
 
 typedef struct
diff --git a/gcc/testsuite/gcc.target/arm/cmse/bitfield-3.c b/gcc/testsuite/gcc.target/arm/cmse/bitfield-3.c
index e8f973e..5875f8df 100644
--- a/gcc/testsuite/gcc.target/arm/cmse/bitfield-3.c
+++ b/gcc/testsuite/gcc.target/arm/cmse/bitfield-3.c
@@ -1,4 +1,4 @@ 
-/* { dg-do run } */
+/* This test is executed only if the execution engine supports CMSE instructions.  */
 /* { dg-options "--save-temps -mcmse -Wl,--section-start,.gnu.sgstubs=0x00400000" } */
 
 typedef struct
diff --git a/gcc/testsuite/gcc.target/arm/cmse/cmse-16.c b/gcc/testsuite/gcc.target/arm/cmse/cmse-16.c
index 3fb0380..6a243d5 100644
--- a/gcc/testsuite/gcc.target/arm/cmse/cmse-16.c
+++ b/gcc/testsuite/gcc.target/arm/cmse/cmse-16.c
@@ -1,4 +1,8 @@ 
-/* { dg-do run } */
+/* This test is executed only if the execution engine supports CMSE instructions.  */
+/* Note that it "passes" on qemu-arm while it shouldn't because that simulator
+   does not model secure memory: it's better to skip it in this case, and rely
+   on do-what-default as set in cmse.exp. (It works as expected with
+   qemu-system-mode).  */
 /* { dg-options "-Os -mcmse" }  */
 
 #include <arm_cmse.h>
diff --git a/gcc/testsuite/gcc.target/arm/cmse/cmse.exp b/gcc/testsuite/gcc.target/arm/cmse/cmse.exp
index 6ce99fe..4da1a46 100644
--- a/gcc/testsuite/gcc.target/arm/cmse/cmse.exp
+++ b/gcc/testsuite/gcc.target/arm/cmse/cmse.exp
@@ -34,7 +34,12 @@  if ![info exists DEFAULT_CFLAGS] then {
 dg-init
 
 set saved-dg-do-what-default ${dg-do-what-default}
-set dg-do-what-default "assemble"
+
+if {[is-effective-target arm_cmse_hw]} then {
+    set dg-do-what-default run
+} else {
+    set dg-do-what-default assemble
+}
 
 set saved-lto_torture_options ${LTO_TORTURE_OPTIONS}
 set LTO_TORTURE_OPTIONS ""
diff --git a/gcc/testsuite/gcc.target/arm/cmse/struct-1.c b/gcc/testsuite/gcc.target/arm/cmse/struct-1.c
index 7555643..75a99f4 100644
--- a/gcc/testsuite/gcc.target/arm/cmse/struct-1.c
+++ b/gcc/testsuite/gcc.target/arm/cmse/struct-1.c
@@ -1,4 +1,4 @@ 
-/* { dg-do run } */
+/* This test is executed only if the execution engine supports CMSE instructions.  */
 /* { dg-options "--save-temps -mcmse -Wl,--section-start,.gnu.sgstubs=0x00400000" } */
 
 typedef struct
diff --git a/gcc/testsuite/lib/target-supports.exp b/gcc/testsuite/lib/target-supports.exp
index 1230d19..9b38b41 100644
--- a/gcc/testsuite/lib/target-supports.exp
+++ b/gcc/testsuite/lib/target-supports.exp
@@ -4861,6 +4861,21 @@  proc check_effective_target_arm_cmse_ok {} {
     } "-mcmse"];
 }
 
+# Return 1 if the target supports executing CMSE instructions, 0
+# otherwise.  Cache the result.
+
+proc check_effective_target_arm_cmse_hw { } {
+    return [check_runtime arm_cmse_hw_available {
+	int __attribute__ ((cmse_nonsecure_entry)) ns_func(void)
+	{
+	    return 0;
+	}
+	int main (void)
+	{
+	    return ns_func();
+	}
+    } "-mcmse -Wl,--section-start,.gnu.sgstubs=0x00400000"]
+}
 # Return 1 if the target supports executing MVE instructions, 0
 # otherwise.