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* [PATCH, ARM] Error out when -mfpu set and targeting Thumb-1
@ 2018-11-29 10:51 Thomas Preudhomme
  2018-11-29 14:52 ` Richard Earnshaw (lists)
  0 siblings, 1 reply; 5+ messages in thread
From: Thomas Preudhomme @ 2018-11-29 10:51 UTC (permalink / raw)
  To: kyrylo.tkachov, Ramana Radhakrishnan, Richard Earnshaw, gcc-patches

[-- Attachment #1: Type: text/plain, Size: 1111 bytes --]

Hi,

FP instructions are only enabled for TARGET_32BIT and TARGET_HARD_FLOAT
but GCC only gives an error when TARGET_HARD_FLOAT is true and -mfpu is
not set. Among other things, it makes some of the cmse tests (eg.
gcc.target/arm/cmse/baseline/softfp.c) fail when targeting
-march=armv8-m.base -mfpu=<something> -mfloat-abi=softfp. This patch
errors out when a Thumb-1 -like target is selected and a FPU is
specified, thus making such tests being skipped.

ChangeLog entries are as follows:

*** gcc/ChangeLog ***

2018-11-28  thomas Preud'homme  <thomas.preudhomme@linaro.org>

    * config/arm/arm.c (arm_options_perform_arch_sanity_checks): Error out
    if targeting Thumb-1 with an FPU specified.

*** gcc/testsuite/ChangeLog ***

2018-11-28  thomas Preud'homme  <thomas.preudhomme@linaro.org>

    * gcc.target/arm/thumb1_mfpu-1.c: New testcase.
    * gcc.target/arm/thumb1_mfpu-2.c: Likewise.

Testing: No testsuite regression when targeting arm-none-eabi Armv6S-M.
Fails as expected when targeting Armv6-M with an -mfpu or a default FPU.
Succeeds without.

Is this ok for stage3?

Best regards,

Thomas

[-- Attachment #2: thumb1_mfpu_error.patch --]
[-- Type: text/x-patch, Size: 3441 bytes --]

From 051e38552d7c596873e0303f6ec4272b26d50900 Mon Sep 17 00:00:00 2001
From: Thomas Preud'homme <thomas.preudhomme@linaro.org>
Date: Tue, 27 Nov 2018 15:52:38 +0000
Subject: [PATCH] [PATCH, ARM] Error out when -mfpu set and targeting Thumb-1

Hi,

FP instructions are only enabled for TARGET_32BIT and TARGET_HARD_FLOAT
but GCC only gives an error when TARGET_HARD_FLOAT is true and -mfpu is
not set. Among other things, it makes some of the cmse tests (eg.
gcc.target/arm/cmse/baseline/softfp.c) fail when targeting
-march=armv8-m.base -mfpu=<something> -mfloat-abi=softfp. This patch
errors out when a Thumb-1 -like target is selected and a FPU is
specified, thus making such tests being skipped.

ChangeLog entries are as follows:

*** gcc/ChangeLog ***

2018-11-28  thomas Preud'homme  <thomas.preudhomme@linaro.org>

	* config/arm/arm.c (arm_options_perform_arch_sanity_checks): Error out
	if targeting Thumb-1 with an FPU specified.

*** gcc/testsuite/ChangeLog ***

2018-11-28  thomas Preud'homme  <thomas.preudhomme@linaro.org>

	* gcc.target/arm/thumb1_mfpu-1.c: New testcase.
	* gcc.target/arm/thumb1_mfpu-2.c: Likewise.

Testing: No testsuite regression when targeting arm-none-eabi Armv6S-M.
Fails as expected when targeting Armv6-M with an -mfpu or a default FPU.
Succeeds without.

Is this ok for stage3?

Best regards,

Thomas
---
 gcc/config/arm/arm.c                         | 3 +++
 gcc/testsuite/gcc.target/arm/thumb1_mfpu-1.c | 7 +++++++
 gcc/testsuite/gcc.target/arm/thumb1_mfpu-2.c | 8 ++++++++
 3 files changed, 18 insertions(+)
 create mode 100644 gcc/testsuite/gcc.target/arm/thumb1_mfpu-1.c
 create mode 100644 gcc/testsuite/gcc.target/arm/thumb1_mfpu-2.c

diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
index 40f0574e32e..1a205123cf5 100644
--- a/gcc/config/arm/arm.c
+++ b/gcc/config/arm/arm.c
@@ -3747,6 +3747,9 @@ arm_options_perform_arch_sanity_checks (void)
     {
       if (arm_abi == ARM_ABI_IWMMXT)
 	arm_pcs_default = ARM_PCS_AAPCS_IWMMXT;
+      else if (TARGET_THUMB1
+	       && bitmap_bit_p (arm_active_target.isa, isa_bit_vfpv2))
+	error ("Thumb-1 does not allow FP instructions");
       else if (TARGET_HARD_FLOAT_ABI)
 	{
 	  arm_pcs_default = ARM_PCS_AAPCS_VFP;
diff --git a/gcc/testsuite/gcc.target/arm/thumb1_mfpu-1.c b/gcc/testsuite/gcc.target/arm/thumb1_mfpu-1.c
new file mode 100644
index 00000000000..5347e63f9b6
--- /dev/null
+++ b/gcc/testsuite/gcc.target/arm/thumb1_mfpu-1.c
@@ -0,0 +1,7 @@
+/* { dg-do compile } */
+/* { dg-require-effective-target arm_thumb1_ok } */
+/* { dg-skip-if "incompatible float ABI" { *-*-* } { "-mfloat-abi=*" } { "-mfloat-abi=softfp" } } */
+/* { dg-options "-mthumb -mfpu=vfp -mfloat-abi=softfp" } */
+/* { dg-error "Thumb-1 does not allow FP instructions" "" { target *-*-* } 0 } */
+
+int foo;
diff --git a/gcc/testsuite/gcc.target/arm/thumb1_mfpu-2.c b/gcc/testsuite/gcc.target/arm/thumb1_mfpu-2.c
new file mode 100644
index 00000000000..941ed26ed01
--- /dev/null
+++ b/gcc/testsuite/gcc.target/arm/thumb1_mfpu-2.c
@@ -0,0 +1,8 @@
+/* { dg-do compile } */
+/* { dg-require-effective-target arm_thumb1_ok } */
+/* { dg-skip-if "incompatible float ABI" { *-*-* } { "-mfloat-abi=*" } { "-mfloat-abi=softfp" } } */
+/* No need to skip in presence of -mfpu since arm_thumb1_ok will already fail
+   due to Thumb-1 with -mfpu which is tested by thumb1_mfpu-1 testcase.  */
+/* { dg-options "-mthumb -mfloat-abi=softfp" } */
+
+int foo;
-- 
2.19.1


^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH, ARM] Error out when -mfpu set and targeting Thumb-1
  2018-11-29 10:51 [PATCH, ARM] Error out when -mfpu set and targeting Thumb-1 Thomas Preudhomme
@ 2018-11-29 14:52 ` Richard Earnshaw (lists)
  2018-12-14 21:16   ` [PATCH, ARM] Do softfloat when -mfpu set, -mfloat-abi=softfp " Thomas Preudhomme
  0 siblings, 1 reply; 5+ messages in thread
From: Richard Earnshaw (lists) @ 2018-11-29 14:52 UTC (permalink / raw)
  To: Thomas Preudhomme, kyrylo.tkachov, Ramana Radhakrishnan, gcc-patches

On 29/11/2018 10:51, Thomas Preudhomme wrote:
> Hi,
> 
> FP instructions are only enabled for TARGET_32BIT and TARGET_HARD_FLOAT
> but GCC only gives an error when TARGET_HARD_FLOAT is true and -mfpu is
> not set. Among other things, it makes some of the cmse tests (eg.
> gcc.target/arm/cmse/baseline/softfp.c) fail when targeting
> -march=armv8-m.base -mfpu=<something> -mfloat-abi=softfp. This patch
> errors out when a Thumb-1 -like target is selected and a FPU is
> specified, thus making such tests being skipped.
> 
> ChangeLog entries are as follows:
> 
> *** gcc/ChangeLog ***
> 
> 2018-11-28  thomas Preud'homme  <thomas.preudhomme@linaro.org>
> 
>     * config/arm/arm.c (arm_options_perform_arch_sanity_checks): Error out
>     if targeting Thumb-1 with an FPU specified.
> 
> *** gcc/testsuite/ChangeLog ***
> 
> 2018-11-28  thomas Preud'homme  <thomas.preudhomme@linaro.org>
> 
>     * gcc.target/arm/thumb1_mfpu-1.c: New testcase.
>     * gcc.target/arm/thumb1_mfpu-2.c: Likewise.
> 
> Testing: No testsuite regression when targeting arm-none-eabi Armv6S-M.
> Fails as expected when targeting Armv6-M with an -mfpu or a default FPU.
> Succeeds without.
> 
> Is this ok for stage3?
> 

This doesn't sound right.  Specifically this bit...

+      else if (TARGET_THUMB1
+	       && bitmap_bit_p (arm_active_target.isa, isa_bit_vfpv2))
+	error ("Thumb-1 does not allow FP instructions");

If I use

    -mcpu=arm1176jzf-s -mfpu=auto -mfloat-abi=softfp -mthumb

then that shouldn't error, since softfp and thumb is, in reality, just
float-abi=soft (as there are no fp instructions in thumb).  We also want
it to work this way so that I can add the thumb/arm attribute to
specific functions and have the compiler use HW float instructions when
they are suitable.


R.

> Best regards,
> 
> Thomas
> 
> 
> thumb1_mfpu_error.patch
> 
> From 051e38552d7c596873e0303f6ec4272b26d50900 Mon Sep 17 00:00:00 2001
> From: Thomas Preud'homme <thomas.preudhomme@linaro.org>
> Date: Tue, 27 Nov 2018 15:52:38 +0000
> Subject: [PATCH] [PATCH, ARM] Error out when -mfpu set and targeting Thumb-1
> 
> Hi,
> 
> FP instructions are only enabled for TARGET_32BIT and TARGET_HARD_FLOAT
> but GCC only gives an error when TARGET_HARD_FLOAT is true and -mfpu is
> not set. Among other things, it makes some of the cmse tests (eg.
> gcc.target/arm/cmse/baseline/softfp.c) fail when targeting
> -march=armv8-m.base -mfpu=<something> -mfloat-abi=softfp. This patch
> errors out when a Thumb-1 -like target is selected and a FPU is
> specified, thus making such tests being skipped.
> 
> ChangeLog entries are as follows:
> 
> *** gcc/ChangeLog ***
> 
> 2018-11-28  thomas Preud'homme  <thomas.preudhomme@linaro.org>
> 
> 	* config/arm/arm.c (arm_options_perform_arch_sanity_checks): Error out
> 	if targeting Thumb-1 with an FPU specified.
> 
> *** gcc/testsuite/ChangeLog ***
> 
> 2018-11-28  thomas Preud'homme  <thomas.preudhomme@linaro.org>
> 
> 	* gcc.target/arm/thumb1_mfpu-1.c: New testcase.
> 	* gcc.target/arm/thumb1_mfpu-2.c: Likewise.
> 
> Testing: No testsuite regression when targeting arm-none-eabi Armv6S-M.
> Fails as expected when targeting Armv6-M with an -mfpu or a default FPU.
> Succeeds without.
> 
> Is this ok for stage3?
> 
> Best regards,
> 
> Thomas
> ---
>  gcc/config/arm/arm.c                         | 3 +++
>  gcc/testsuite/gcc.target/arm/thumb1_mfpu-1.c | 7 +++++++
>  gcc/testsuite/gcc.target/arm/thumb1_mfpu-2.c | 8 ++++++++
>  3 files changed, 18 insertions(+)
>  create mode 100644 gcc/testsuite/gcc.target/arm/thumb1_mfpu-1.c
>  create mode 100644 gcc/testsuite/gcc.target/arm/thumb1_mfpu-2.c
> 
> diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
> index 40f0574e32e..1a205123cf5 100644
> --- a/gcc/config/arm/arm.c
> +++ b/gcc/config/arm/arm.c
> @@ -3747,6 +3747,9 @@ arm_options_perform_arch_sanity_checks (void)
>      {
>        if (arm_abi == ARM_ABI_IWMMXT)
>  	arm_pcs_default = ARM_PCS_AAPCS_IWMMXT;
> +      else if (TARGET_THUMB1
> +	       && bitmap_bit_p (arm_active_target.isa, isa_bit_vfpv2))
> +	error ("Thumb-1 does not allow FP instructions");
>        else if (TARGET_HARD_FLOAT_ABI)
>  	{
>  	  arm_pcs_default = ARM_PCS_AAPCS_VFP;
> diff --git a/gcc/testsuite/gcc.target/arm/thumb1_mfpu-1.c b/gcc/testsuite/gcc.target/arm/thumb1_mfpu-1.c
> new file mode 100644
> index 00000000000..5347e63f9b6
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/arm/thumb1_mfpu-1.c
> @@ -0,0 +1,7 @@
> +/* { dg-do compile } */
> +/* { dg-require-effective-target arm_thumb1_ok } */
> +/* { dg-skip-if "incompatible float ABI" { *-*-* } { "-mfloat-abi=*" } { "-mfloat-abi=softfp" } } */
> +/* { dg-options "-mthumb -mfpu=vfp -mfloat-abi=softfp" } */
> +/* { dg-error "Thumb-1 does not allow FP instructions" "" { target *-*-* } 0 } */
> +
> +int foo;
> diff --git a/gcc/testsuite/gcc.target/arm/thumb1_mfpu-2.c b/gcc/testsuite/gcc.target/arm/thumb1_mfpu-2.c
> new file mode 100644
> index 00000000000..941ed26ed01
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/arm/thumb1_mfpu-2.c
> @@ -0,0 +1,8 @@
> +/* { dg-do compile } */
> +/* { dg-require-effective-target arm_thumb1_ok } */
> +/* { dg-skip-if "incompatible float ABI" { *-*-* } { "-mfloat-abi=*" } { "-mfloat-abi=softfp" } } */
> +/* No need to skip in presence of -mfpu since arm_thumb1_ok will already fail
> +   due to Thumb-1 with -mfpu which is tested by thumb1_mfpu-1 testcase.  */
> +/* { dg-options "-mthumb -mfloat-abi=softfp" } */
> +
> +int foo;
> 

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH, ARM] Do softfloat when -mfpu set, -mfloat-abi=softfp and targeting Thumb-1
  2018-11-29 14:52 ` Richard Earnshaw (lists)
@ 2018-12-14 21:16   ` Thomas Preudhomme
  2018-12-19 14:13     ` Richard Earnshaw (lists)
  0 siblings, 1 reply; 5+ messages in thread
From: Thomas Preudhomme @ 2018-12-14 21:16 UTC (permalink / raw)
  To: Richard Earnshaw; +Cc: kyrylo.tkachov, Ramana Radhakrishnan, gcc-patches

[-- Attachment #1: Type: text/plain, Size: 6978 bytes --]

Hi Richard,

Thanks for catching the problem with this approach. Hopefully this
version should solve the real problem:


FP instructions are only enabled for TARGET_32BIT and TARGET_HARD_FLOAT
but GCC only gives an error when TARGET_HARD_FLOAT is true and -mfpu is
not set. Among other things, it makes some of the cmse tests (eg.
gcc.target/arm/cmse/baseline/softfp.c) fail when targeting
-march=armv8-m.base -mcmse -mfpu=<something> -mfloat-abi=softfp. This
patch adds an extra check for TARGET_32BIT to TARGET_HARD_FLOAT such
that it is false on TARGET_THUMB1 targets even when a FPU is specified.

ChangeLog entries are as follows:

*** gcc/ChangeLog ***

2018-12-14  thomas Preud'homme  <thomas.preudhomme@linaro.org>

        * config/arm/arm.h (TARGET_HARD_FLOAT): Restrict to TARGET_32BIT
        targets.

*** gcc/testsuite/ChangeLog ***

2018-12-14  thomas Preud'homme  <thomas.preudhomme@linaro.org>

        * gcc.target/arm/cmse/baseline/softfp.c: Force an FPU.

Testing: No testsuite regression when targeting arm-none-eabi Armv6S-M
with -mfloat-abi=softfp

Is this ok for stage3?

Best regards,

Thomas

On Thu, 29 Nov 2018 at 14:52, Richard Earnshaw (lists)
<Richard.Earnshaw@arm.com> wrote:
>
> On 29/11/2018 10:51, Thomas Preudhomme wrote:
> > Hi,
> >
> > FP instructions are only enabled for TARGET_32BIT and TARGET_HARD_FLOAT
> > but GCC only gives an error when TARGET_HARD_FLOAT is true and -mfpu is
> > not set. Among other things, it makes some of the cmse tests (eg.
> > gcc.target/arm/cmse/baseline/softfp.c) fail when targeting
> > -march=armv8-m.base -mfpu=<something> -mfloat-abi=softfp. This patch
> > errors out when a Thumb-1 -like target is selected and a FPU is
> > specified, thus making such tests being skipped.
> >
> > ChangeLog entries are as follows:
> >
> > *** gcc/ChangeLog ***
> >
> > 2018-11-28  thomas Preud'homme  <thomas.preudhomme@linaro.org>
> >
> >     * config/arm/arm.c (arm_options_perform_arch_sanity_checks): Error out
> >     if targeting Thumb-1 with an FPU specified.
> >
> > *** gcc/testsuite/ChangeLog ***
> >
> > 2018-11-28  thomas Preud'homme  <thomas.preudhomme@linaro.org>
> >
> >     * gcc.target/arm/thumb1_mfpu-1.c: New testcase.
> >     * gcc.target/arm/thumb1_mfpu-2.c: Likewise.
> >
> > Testing: No testsuite regression when targeting arm-none-eabi Armv6S-M.
> > Fails as expected when targeting Armv6-M with an -mfpu or a default FPU.
> > Succeeds without.
> >
> > Is this ok for stage3?
> >
>
> This doesn't sound right.  Specifically this bit...
>
> +      else if (TARGET_THUMB1
> +              && bitmap_bit_p (arm_active_target.isa, isa_bit_vfpv2))
> +       error ("Thumb-1 does not allow FP instructions");
>
> If I use
>
>     -mcpu=arm1176jzf-s -mfpu=auto -mfloat-abi=softfp -mthumb
>
> then that shouldn't error, since softfp and thumb is, in reality, just
> float-abi=soft (as there are no fp instructions in thumb).  We also want
> it to work this way so that I can add the thumb/arm attribute to
> specific functions and have the compiler use HW float instructions when
> they are suitable.
>
>
> R.
>
> > Best regards,
> >
> > Thomas
> >
> >
> > thumb1_mfpu_error.patch
> >
> > From 051e38552d7c596873e0303f6ec4272b26d50900 Mon Sep 17 00:00:00 2001
> > From: Thomas Preud'homme <thomas.preudhomme@linaro.org>
> > Date: Tue, 27 Nov 2018 15:52:38 +0000
> > Subject: [PATCH] [PATCH, ARM] Error out when -mfpu set and targeting Thumb-1
> >
> > Hi,
> >
> > FP instructions are only enabled for TARGET_32BIT and TARGET_HARD_FLOAT
> > but GCC only gives an error when TARGET_HARD_FLOAT is true and -mfpu is
> > not set. Among other things, it makes some of the cmse tests (eg.
> > gcc.target/arm/cmse/baseline/softfp.c) fail when targeting
> > -march=armv8-m.base -mfpu=<something> -mfloat-abi=softfp. This patch
> > errors out when a Thumb-1 -like target is selected and a FPU is
> > specified, thus making such tests being skipped.
> >
> > ChangeLog entries are as follows:
> >
> > *** gcc/ChangeLog ***
> >
> > 2018-11-28  thomas Preud'homme  <thomas.preudhomme@linaro.org>
> >
> >       * config/arm/arm.c (arm_options_perform_arch_sanity_checks): Error out
> >       if targeting Thumb-1 with an FPU specified.
> >
> > *** gcc/testsuite/ChangeLog ***
> >
> > 2018-11-28  thomas Preud'homme  <thomas.preudhomme@linaro.org>
> >
> >       * gcc.target/arm/thumb1_mfpu-1.c: New testcase.
> >       * gcc.target/arm/thumb1_mfpu-2.c: Likewise.
> >
> > Testing: No testsuite regression when targeting arm-none-eabi Armv6S-M.
> > Fails as expected when targeting Armv6-M with an -mfpu or a default FPU.
> > Succeeds without.
> >
> > Is this ok for stage3?
> >
> > Best regards,
> >
> > Thomas
> > ---
> >  gcc/config/arm/arm.c                         | 3 +++
> >  gcc/testsuite/gcc.target/arm/thumb1_mfpu-1.c | 7 +++++++
> >  gcc/testsuite/gcc.target/arm/thumb1_mfpu-2.c | 8 ++++++++
> >  3 files changed, 18 insertions(+)
> >  create mode 100644 gcc/testsuite/gcc.target/arm/thumb1_mfpu-1.c
> >  create mode 100644 gcc/testsuite/gcc.target/arm/thumb1_mfpu-2.c
> >
> > diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
> > index 40f0574e32e..1a205123cf5 100644
> > --- a/gcc/config/arm/arm.c
> > +++ b/gcc/config/arm/arm.c
> > @@ -3747,6 +3747,9 @@ arm_options_perform_arch_sanity_checks (void)
> >      {
> >        if (arm_abi == ARM_ABI_IWMMXT)
> >       arm_pcs_default = ARM_PCS_AAPCS_IWMMXT;
> > +      else if (TARGET_THUMB1
> > +            && bitmap_bit_p (arm_active_target.isa, isa_bit_vfpv2))
> > +     error ("Thumb-1 does not allow FP instructions");
> >        else if (TARGET_HARD_FLOAT_ABI)
> >       {
> >         arm_pcs_default = ARM_PCS_AAPCS_VFP;
> > diff --git a/gcc/testsuite/gcc.target/arm/thumb1_mfpu-1.c b/gcc/testsuite/gcc.target/arm/thumb1_mfpu-1.c
> > new file mode 100644
> > index 00000000000..5347e63f9b6
> > --- /dev/null
> > +++ b/gcc/testsuite/gcc.target/arm/thumb1_mfpu-1.c
> > @@ -0,0 +1,7 @@
> > +/* { dg-do compile } */
> > +/* { dg-require-effective-target arm_thumb1_ok } */
> > +/* { dg-skip-if "incompatible float ABI" { *-*-* } { "-mfloat-abi=*" } { "-mfloat-abi=softfp" } } */
> > +/* { dg-options "-mthumb -mfpu=vfp -mfloat-abi=softfp" } */
> > +/* { dg-error "Thumb-1 does not allow FP instructions" "" { target *-*-* } 0 } */
> > +
> > +int foo;
> > diff --git a/gcc/testsuite/gcc.target/arm/thumb1_mfpu-2.c b/gcc/testsuite/gcc.target/arm/thumb1_mfpu-2.c
> > new file mode 100644
> > index 00000000000..941ed26ed01
> > --- /dev/null
> > +++ b/gcc/testsuite/gcc.target/arm/thumb1_mfpu-2.c
> > @@ -0,0 +1,8 @@
> > +/* { dg-do compile } */
> > +/* { dg-require-effective-target arm_thumb1_ok } */
> > +/* { dg-skip-if "incompatible float ABI" { *-*-* } { "-mfloat-abi=*" } { "-mfloat-abi=softfp" } } */
> > +/* No need to skip in presence of -mfpu since arm_thumb1_ok will already fail
> > +   due to Thumb-1 with -mfpu which is tested by thumb1_mfpu-1 testcase.  */
> > +/* { dg-options "-mthumb -mfloat-abi=softfp" } */
> > +
> > +int foo;
> >
>

[-- Attachment #2: softfloat_mfpu_set_softfp_thumb1.patch --]
[-- Type: text/x-patch, Size: 2613 bytes --]

From 7c056f386df458f08c0ae367edc7050d53cd6602 Mon Sep 17 00:00:00 2001
From: Thomas Preud'homme <thomas.preudhomme@linaro.org>
Date: Tue, 27 Nov 2018 15:52:38 +0000
Subject: [PATCH] [PATCH, ARM] Do softfloat when -mfpu set, -mfloat-abi=softfp
 and targeting Thumb-1

Hi,

FP instructions are only enabled for TARGET_32BIT and TARGET_HARD_FLOAT
but GCC only gives an error when TARGET_HARD_FLOAT is true and -mfpu is
not set. Among other things, it makes some of the cmse tests (eg.
gcc.target/arm/cmse/baseline/softfp.c) fail when targeting
-march=armv8-m.base -mcmse -mfpu=<something> -mfloat-abi=softfp. This
patch adds an extra check for TARGET_32BIT to TARGET_HARD_FLOAT such
that it is false on TARGET_THUMB1 targets even when a FPU is specified.

ChangeLog entries are as follows:

*** gcc/ChangeLog ***

2018-12-14  thomas Preud'homme  <thomas.preudhomme@linaro.org>

	* config/arm/arm.h (TARGET_HARD_FLOAT): Restrict to TARGET_32BIT
	targets.

*** gcc/testsuite/ChangeLog ***

2018-12-14  thomas Preud'homme  <thomas.preudhomme@linaro.org>

	* gcc.target/arm/cmse/baseline/softfp.c: Force an FPU.

Testing: No testsuite regression when targeting arm-none-eabi Armv6S-M.

Is this ok for stage3?

Best regards,

Thomas
---
 gcc/config/arm/arm.h                                | 3 ++-
 gcc/testsuite/gcc.target/arm/cmse/baseline/softfp.c | 4 +++-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/gcc/config/arm/arm.h b/gcc/config/arm/arm.h
index 8472312487b..149243d0978 100644
--- a/gcc/config/arm/arm.h
+++ b/gcc/config/arm/arm.h
@@ -125,7 +125,8 @@ extern tree arm_fp16_type_node;
 /* Use hardware floating point instructions. */
 #define TARGET_HARD_FLOAT	(arm_float_abi != ARM_FLOAT_ABI_SOFT	\
 				 && bitmap_bit_p (arm_active_target.isa, \
-						  isa_bit_vfpv2))
+						  isa_bit_vfpv2) \
+				 && TARGET_32BIT)
 #define TARGET_SOFT_FLOAT	(!TARGET_HARD_FLOAT)
 /* User has permitted use of FP instructions, if they exist for this
    target.  */
diff --git a/gcc/testsuite/gcc.target/arm/cmse/baseline/softfp.c b/gcc/testsuite/gcc.target/arm/cmse/baseline/softfp.c
index 3d383ff6ee1..30b3eec078c 100644
--- a/gcc/testsuite/gcc.target/arm/cmse/baseline/softfp.c
+++ b/gcc/testsuite/gcc.target/arm/cmse/baseline/softfp.c
@@ -1,5 +1,7 @@
 /* { dg-do compile } */
-/* { dg-options "-mcmse -mfloat-abi=softfp" } */
+/* Force an FPU to test that it is ignored for Thumb-1 -like targets and that
+   no clearing of VFP register occurs.  */
+/* { dg-options "-mcmse -mfloat-abi=softfp -mfpu=fpv5-d16" } */
 
 double __attribute__ ((cmse_nonsecure_call)) (*bar) (float, double);
 
-- 
2.19.1


^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH, ARM] Do softfloat when -mfpu set, -mfloat-abi=softfp and targeting Thumb-1
  2018-12-14 21:16   ` [PATCH, ARM] Do softfloat when -mfpu set, -mfloat-abi=softfp " Thomas Preudhomme
@ 2018-12-19 14:13     ` Richard Earnshaw (lists)
  2018-12-19 15:03       ` Thomas Preudhomme
  0 siblings, 1 reply; 5+ messages in thread
From: Richard Earnshaw (lists) @ 2018-12-19 14:13 UTC (permalink / raw)
  To: Thomas Preudhomme; +Cc: kyrylo.tkachov, Ramana Radhakrishnan, gcc-patches

On 14/12/2018 21:15, Thomas Preudhomme wrote:
> Hi Richard,
> 
> Thanks for catching the problem with this approach. Hopefully this
> version should solve the real problem:
> 
> 
> FP instructions are only enabled for TARGET_32BIT and TARGET_HARD_FLOAT
> but GCC only gives an error when TARGET_HARD_FLOAT is true and -mfpu is
> not set. Among other things, it makes some of the cmse tests (eg.
> gcc.target/arm/cmse/baseline/softfp.c) fail when targeting
> -march=armv8-m.base -mcmse -mfpu=<something> -mfloat-abi=softfp. This
> patch adds an extra check for TARGET_32BIT to TARGET_HARD_FLOAT such
> that it is false on TARGET_THUMB1 targets even when a FPU is specified.
> 
> ChangeLog entries are as follows:
> 
> *** gcc/ChangeLog ***
> 
> 2018-12-14  thomas Preud'homme  <thomas.preudhomme@linaro.org>
> 
>         * config/arm/arm.h (TARGET_HARD_FLOAT): Restrict to TARGET_32BIT
>         targets.

Yes, this is better.  And with this change, I think this line:

	      if (TARGET_HARD_FLOAT && !TARGET_THUMB1)

in output_return_instruction() can be collapsed into simply


	if (TARGET_HARD_FLOAT)

OK with that change.

R.

> 
> *** gcc/testsuite/ChangeLog ***
> 
> 2018-12-14  thomas Preud'homme  <thomas.preudhomme@linaro.org>
> 
>         * gcc.target/arm/cmse/baseline/softfp.c: Force an FPU.
> 
> Testing: No testsuite regression when targeting arm-none-eabi Armv6S-M
> with -mfloat-abi=softfp
> 
> Is this ok for stage3?
> 
> Best regards,
> 
> Thomas
> 
> On Thu, 29 Nov 2018 at 14:52, Richard Earnshaw (lists)
> <Richard.Earnshaw@arm.com> wrote:
>>
>> On 29/11/2018 10:51, Thomas Preudhomme wrote:
>>> Hi,
>>>
>>> FP instructions are only enabled for TARGET_32BIT and TARGET_HARD_FLOAT
>>> but GCC only gives an error when TARGET_HARD_FLOAT is true and -mfpu is
>>> not set. Among other things, it makes some of the cmse tests (eg.
>>> gcc.target/arm/cmse/baseline/softfp.c) fail when targeting
>>> -march=armv8-m.base -mfpu=<something> -mfloat-abi=softfp. This patch
>>> errors out when a Thumb-1 -like target is selected and a FPU is
>>> specified, thus making such tests being skipped.
>>>
>>> ChangeLog entries are as follows:
>>>
>>> *** gcc/ChangeLog ***
>>>
>>> 2018-11-28  thomas Preud'homme  <thomas.preudhomme@linaro.org>
>>>
>>>     * config/arm/arm.c (arm_options_perform_arch_sanity_checks): Error out
>>>     if targeting Thumb-1 with an FPU specified.
>>>
>>> *** gcc/testsuite/ChangeLog ***
>>>
>>> 2018-11-28  thomas Preud'homme  <thomas.preudhomme@linaro.org>
>>>
>>>     * gcc.target/arm/thumb1_mfpu-1.c: New testcase.
>>>     * gcc.target/arm/thumb1_mfpu-2.c: Likewise.
>>>
>>> Testing: No testsuite regression when targeting arm-none-eabi Armv6S-M.
>>> Fails as expected when targeting Armv6-M with an -mfpu or a default FPU.
>>> Succeeds without.
>>>
>>> Is this ok for stage3?
>>>
>>
>> This doesn't sound right.  Specifically this bit...
>>
>> +      else if (TARGET_THUMB1
>> +              && bitmap_bit_p (arm_active_target.isa, isa_bit_vfpv2))
>> +       error ("Thumb-1 does not allow FP instructions");
>>
>> If I use
>>
>>     -mcpu=arm1176jzf-s -mfpu=auto -mfloat-abi=softfp -mthumb
>>
>> then that shouldn't error, since softfp and thumb is, in reality, just
>> float-abi=soft (as there are no fp instructions in thumb).  We also want
>> it to work this way so that I can add the thumb/arm attribute to
>> specific functions and have the compiler use HW float instructions when
>> they are suitable.
>>
>>
>> R.
>>
>>> Best regards,
>>>
>>> Thomas
>>>
>>>
>>> thumb1_mfpu_error.patch
>>>
>>> From 051e38552d7c596873e0303f6ec4272b26d50900 Mon Sep 17 00:00:00 2001
>>> From: Thomas Preud'homme <thomas.preudhomme@linaro.org>
>>> Date: Tue, 27 Nov 2018 15:52:38 +0000
>>> Subject: [PATCH] [PATCH, ARM] Error out when -mfpu set and targeting Thumb-1
>>>
>>> Hi,
>>>
>>> FP instructions are only enabled for TARGET_32BIT and TARGET_HARD_FLOAT
>>> but GCC only gives an error when TARGET_HARD_FLOAT is true and -mfpu is
>>> not set. Among other things, it makes some of the cmse tests (eg.
>>> gcc.target/arm/cmse/baseline/softfp.c) fail when targeting
>>> -march=armv8-m.base -mfpu=<something> -mfloat-abi=softfp. This patch
>>> errors out when a Thumb-1 -like target is selected and a FPU is
>>> specified, thus making such tests being skipped.
>>>
>>> ChangeLog entries are as follows:
>>>
>>> *** gcc/ChangeLog ***
>>>
>>> 2018-11-28  thomas Preud'homme  <thomas.preudhomme@linaro.org>
>>>
>>>       * config/arm/arm.c (arm_options_perform_arch_sanity_checks): Error out
>>>       if targeting Thumb-1 with an FPU specified.
>>>
>>> *** gcc/testsuite/ChangeLog ***
>>>
>>> 2018-11-28  thomas Preud'homme  <thomas.preudhomme@linaro.org>
>>>
>>>       * gcc.target/arm/thumb1_mfpu-1.c: New testcase.
>>>       * gcc.target/arm/thumb1_mfpu-2.c: Likewise.
>>>
>>> Testing: No testsuite regression when targeting arm-none-eabi Armv6S-M.
>>> Fails as expected when targeting Armv6-M with an -mfpu or a default FPU.
>>> Succeeds without.
>>>
>>> Is this ok for stage3?
>>>
>>> Best regards,
>>>
>>> Thomas
>>> ---
>>>  gcc/config/arm/arm.c                         | 3 +++
>>>  gcc/testsuite/gcc.target/arm/thumb1_mfpu-1.c | 7 +++++++
>>>  gcc/testsuite/gcc.target/arm/thumb1_mfpu-2.c | 8 ++++++++
>>>  3 files changed, 18 insertions(+)
>>>  create mode 100644 gcc/testsuite/gcc.target/arm/thumb1_mfpu-1.c
>>>  create mode 100644 gcc/testsuite/gcc.target/arm/thumb1_mfpu-2.c
>>>
>>> diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
>>> index 40f0574e32e..1a205123cf5 100644
>>> --- a/gcc/config/arm/arm.c
>>> +++ b/gcc/config/arm/arm.c
>>> @@ -3747,6 +3747,9 @@ arm_options_perform_arch_sanity_checks (void)
>>>      {
>>>        if (arm_abi == ARM_ABI_IWMMXT)
>>>       arm_pcs_default = ARM_PCS_AAPCS_IWMMXT;
>>> +      else if (TARGET_THUMB1
>>> +            && bitmap_bit_p (arm_active_target.isa, isa_bit_vfpv2))
>>> +     error ("Thumb-1 does not allow FP instructions");
>>>        else if (TARGET_HARD_FLOAT_ABI)
>>>       {
>>>         arm_pcs_default = ARM_PCS_AAPCS_VFP;
>>> diff --git a/gcc/testsuite/gcc.target/arm/thumb1_mfpu-1.c b/gcc/testsuite/gcc.target/arm/thumb1_mfpu-1.c
>>> new file mode 100644
>>> index 00000000000..5347e63f9b6
>>> --- /dev/null
>>> +++ b/gcc/testsuite/gcc.target/arm/thumb1_mfpu-1.c
>>> @@ -0,0 +1,7 @@
>>> +/* { dg-do compile } */
>>> +/* { dg-require-effective-target arm_thumb1_ok } */
>>> +/* { dg-skip-if "incompatible float ABI" { *-*-* } { "-mfloat-abi=*" } { "-mfloat-abi=softfp" } } */
>>> +/* { dg-options "-mthumb -mfpu=vfp -mfloat-abi=softfp" } */
>>> +/* { dg-error "Thumb-1 does not allow FP instructions" "" { target *-*-* } 0 } */
>>> +
>>> +int foo;
>>> diff --git a/gcc/testsuite/gcc.target/arm/thumb1_mfpu-2.c b/gcc/testsuite/gcc.target/arm/thumb1_mfpu-2.c
>>> new file mode 100644
>>> index 00000000000..941ed26ed01
>>> --- /dev/null
>>> +++ b/gcc/testsuite/gcc.target/arm/thumb1_mfpu-2.c
>>> @@ -0,0 +1,8 @@
>>> +/* { dg-do compile } */
>>> +/* { dg-require-effective-target arm_thumb1_ok } */
>>> +/* { dg-skip-if "incompatible float ABI" { *-*-* } { "-mfloat-abi=*" } { "-mfloat-abi=softfp" } } */
>>> +/* No need to skip in presence of -mfpu since arm_thumb1_ok will already fail
>>> +   due to Thumb-1 with -mfpu which is tested by thumb1_mfpu-1 testcase.  */
>>> +/* { dg-options "-mthumb -mfloat-abi=softfp" } */
>>> +
>>> +int foo;
>>>
>>
>>
>> softfloat_mfpu_set_softfp_thumb1.patch
>>
>> From 7c056f386df458f08c0ae367edc7050d53cd6602 Mon Sep 17 00:00:00 2001
>> From: Thomas Preud'homme <thomas.preudhomme@linaro.org>
>> Date: Tue, 27 Nov 2018 15:52:38 +0000
>> Subject: [PATCH] [PATCH, ARM] Do softfloat when -mfpu set, -mfloat-abi=softfp
>>  and targeting Thumb-1
>>
>> Hi,
>>
>> FP instructions are only enabled for TARGET_32BIT and TARGET_HARD_FLOAT
>> but GCC only gives an error when TARGET_HARD_FLOAT is true and -mfpu is
>> not set. Among other things, it makes some of the cmse tests (eg.
>> gcc.target/arm/cmse/baseline/softfp.c) fail when targeting
>> -march=armv8-m.base -mcmse -mfpu=<something> -mfloat-abi=softfp. This
>> patch adds an extra check for TARGET_32BIT to TARGET_HARD_FLOAT such
>> that it is false on TARGET_THUMB1 targets even when a FPU is specified.
>>
>> ChangeLog entries are as follows:
>>
>> *** gcc/ChangeLog ***
>>
>> 2018-12-14  thomas Preud'homme  <thomas.preudhomme@linaro.org>
>>
>> 	* config/arm/arm.h (TARGET_HARD_FLOAT): Restrict to TARGET_32BIT
>> 	targets.
>>
>> *** gcc/testsuite/ChangeLog ***
>>
>> 2018-12-14  thomas Preud'homme  <thomas.preudhomme@linaro.org>
>>
>> 	* gcc.target/arm/cmse/baseline/softfp.c: Force an FPU.
>>
>> Testing: No testsuite regression when targeting arm-none-eabi Armv6S-M.
>>
>> Is this ok for stage3?
>>
>> Best regards,
>>
>> Thomas
>> ---
>>  gcc/config/arm/arm.h                                | 3 ++-
>>  gcc/testsuite/gcc.target/arm/cmse/baseline/softfp.c | 4 +++-
>>  2 files changed, 5 insertions(+), 2 deletions(-)
>>
>> diff --git a/gcc/config/arm/arm.h b/gcc/config/arm/arm.h
>> index 8472312487b..149243d0978 100644
>> --- a/gcc/config/arm/arm.h
>> +++ b/gcc/config/arm/arm.h
>> @@ -125,7 +125,8 @@ extern tree arm_fp16_type_node;
>>  /* Use hardware floating point instructions. */
>>  #define TARGET_HARD_FLOAT	(arm_float_abi != ARM_FLOAT_ABI_SOFT	\
>>  				 && bitmap_bit_p (arm_active_target.isa, \
>> -						  isa_bit_vfpv2))
>> +						  isa_bit_vfpv2) \
>> +				 && TARGET_32BIT)
>>  #define TARGET_SOFT_FLOAT	(!TARGET_HARD_FLOAT)
>>  /* User has permitted use of FP instructions, if they exist for this
>>     target.  */
>> diff --git a/gcc/testsuite/gcc.target/arm/cmse/baseline/softfp.c b/gcc/testsuite/gcc.target/arm/cmse/baseline/softfp.c
>> index 3d383ff6ee1..30b3eec078c 100644
>> --- a/gcc/testsuite/gcc.target/arm/cmse/baseline/softfp.c
>> +++ b/gcc/testsuite/gcc.target/arm/cmse/baseline/softfp.c
>> @@ -1,5 +1,7 @@
>>  /* { dg-do compile } */
>> -/* { dg-options "-mcmse -mfloat-abi=softfp" } */
>> +/* Force an FPU to test that it is ignored for Thumb-1 -like targets and that
>> +   no clearing of VFP register occurs.  */
>> +/* { dg-options "-mcmse -mfloat-abi=softfp -mfpu=fpv5-d16" } */
>>  
>>  double __attribute__ ((cmse_nonsecure_call)) (*bar) (float, double);
>>  

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH, ARM] Do softfloat when -mfpu set, -mfloat-abi=softfp and targeting Thumb-1
  2018-12-19 14:13     ` Richard Earnshaw (lists)
@ 2018-12-19 15:03       ` Thomas Preudhomme
  0 siblings, 0 replies; 5+ messages in thread
From: Thomas Preudhomme @ 2018-12-19 15:03 UTC (permalink / raw)
  To: Richard Earnshaw; +Cc: kyrylo.tkachov, Ramana Radhakrishnan, gcc-patches

[-- Attachment #1: Type: text/plain, Size: 11048 bytes --]

Good catch.

Committed patch in attachment. Best regards,

Thomas
On Wed, 19 Dec 2018 at 14:13, Richard Earnshaw (lists)
<Richard.Earnshaw@arm.com> wrote:
>
> On 14/12/2018 21:15, Thomas Preudhomme wrote:
> > Hi Richard,
> >
> > Thanks for catching the problem with this approach. Hopefully this
> > version should solve the real problem:
> >
> >
> > FP instructions are only enabled for TARGET_32BIT and TARGET_HARD_FLOAT
> > but GCC only gives an error when TARGET_HARD_FLOAT is true and -mfpu is
> > not set. Among other things, it makes some of the cmse tests (eg.
> > gcc.target/arm/cmse/baseline/softfp.c) fail when targeting
> > -march=armv8-m.base -mcmse -mfpu=<something> -mfloat-abi=softfp. This
> > patch adds an extra check for TARGET_32BIT to TARGET_HARD_FLOAT such
> > that it is false on TARGET_THUMB1 targets even when a FPU is specified.
> >
> > ChangeLog entries are as follows:
> >
> > *** gcc/ChangeLog ***
> >
> > 2018-12-14  thomas Preud'homme  <thomas.preudhomme@linaro.org>
> >
> >         * config/arm/arm.h (TARGET_HARD_FLOAT): Restrict to TARGET_32BIT
> >         targets.
>
> Yes, this is better.  And with this change, I think this line:
>
>               if (TARGET_HARD_FLOAT && !TARGET_THUMB1)
>
> in output_return_instruction() can be collapsed into simply
>
>
>         if (TARGET_HARD_FLOAT)
>
> OK with that change.
>
> R.
>
> >
> > *** gcc/testsuite/ChangeLog ***
> >
> > 2018-12-14  thomas Preud'homme  <thomas.preudhomme@linaro.org>
> >
> >         * gcc.target/arm/cmse/baseline/softfp.c: Force an FPU.
> >
> > Testing: No testsuite regression when targeting arm-none-eabi Armv6S-M
> > with -mfloat-abi=softfp
> >
> > Is this ok for stage3?
> >
> > Best regards,
> >
> > Thomas
> >
> > On Thu, 29 Nov 2018 at 14:52, Richard Earnshaw (lists)
> > <Richard.Earnshaw@arm.com> wrote:
> >>
> >> On 29/11/2018 10:51, Thomas Preudhomme wrote:
> >>> Hi,
> >>>
> >>> FP instructions are only enabled for TARGET_32BIT and TARGET_HARD_FLOAT
> >>> but GCC only gives an error when TARGET_HARD_FLOAT is true and -mfpu is
> >>> not set. Among other things, it makes some of the cmse tests (eg.
> >>> gcc.target/arm/cmse/baseline/softfp.c) fail when targeting
> >>> -march=armv8-m.base -mfpu=<something> -mfloat-abi=softfp. This patch
> >>> errors out when a Thumb-1 -like target is selected and a FPU is
> >>> specified, thus making such tests being skipped.
> >>>
> >>> ChangeLog entries are as follows:
> >>>
> >>> *** gcc/ChangeLog ***
> >>>
> >>> 2018-11-28  thomas Preud'homme  <thomas.preudhomme@linaro.org>
> >>>
> >>>     * config/arm/arm.c (arm_options_perform_arch_sanity_checks): Error out
> >>>     if targeting Thumb-1 with an FPU specified.
> >>>
> >>> *** gcc/testsuite/ChangeLog ***
> >>>
> >>> 2018-11-28  thomas Preud'homme  <thomas.preudhomme@linaro.org>
> >>>
> >>>     * gcc.target/arm/thumb1_mfpu-1.c: New testcase.
> >>>     * gcc.target/arm/thumb1_mfpu-2.c: Likewise.
> >>>
> >>> Testing: No testsuite regression when targeting arm-none-eabi Armv6S-M.
> >>> Fails as expected when targeting Armv6-M with an -mfpu or a default FPU.
> >>> Succeeds without.
> >>>
> >>> Is this ok for stage3?
> >>>
> >>
> >> This doesn't sound right.  Specifically this bit...
> >>
> >> +      else if (TARGET_THUMB1
> >> +              && bitmap_bit_p (arm_active_target.isa, isa_bit_vfpv2))
> >> +       error ("Thumb-1 does not allow FP instructions");
> >>
> >> If I use
> >>
> >>     -mcpu=arm1176jzf-s -mfpu=auto -mfloat-abi=softfp -mthumb
> >>
> >> then that shouldn't error, since softfp and thumb is, in reality, just
> >> float-abi=soft (as there are no fp instructions in thumb).  We also want
> >> it to work this way so that I can add the thumb/arm attribute to
> >> specific functions and have the compiler use HW float instructions when
> >> they are suitable.
> >>
> >>
> >> R.
> >>
> >>> Best regards,
> >>>
> >>> Thomas
> >>>
> >>>
> >>> thumb1_mfpu_error.patch
> >>>
> >>> From 051e38552d7c596873e0303f6ec4272b26d50900 Mon Sep 17 00:00:00 2001
> >>> From: Thomas Preud'homme <thomas.preudhomme@linaro.org>
> >>> Date: Tue, 27 Nov 2018 15:52:38 +0000
> >>> Subject: [PATCH] [PATCH, ARM] Error out when -mfpu set and targeting Thumb-1
> >>>
> >>> Hi,
> >>>
> >>> FP instructions are only enabled for TARGET_32BIT and TARGET_HARD_FLOAT
> >>> but GCC only gives an error when TARGET_HARD_FLOAT is true and -mfpu is
> >>> not set. Among other things, it makes some of the cmse tests (eg.
> >>> gcc.target/arm/cmse/baseline/softfp.c) fail when targeting
> >>> -march=armv8-m.base -mfpu=<something> -mfloat-abi=softfp. This patch
> >>> errors out when a Thumb-1 -like target is selected and a FPU is
> >>> specified, thus making such tests being skipped.
> >>>
> >>> ChangeLog entries are as follows:
> >>>
> >>> *** gcc/ChangeLog ***
> >>>
> >>> 2018-11-28  thomas Preud'homme  <thomas.preudhomme@linaro.org>
> >>>
> >>>       * config/arm/arm.c (arm_options_perform_arch_sanity_checks): Error out
> >>>       if targeting Thumb-1 with an FPU specified.
> >>>
> >>> *** gcc/testsuite/ChangeLog ***
> >>>
> >>> 2018-11-28  thomas Preud'homme  <thomas.preudhomme@linaro.org>
> >>>
> >>>       * gcc.target/arm/thumb1_mfpu-1.c: New testcase.
> >>>       * gcc.target/arm/thumb1_mfpu-2.c: Likewise.
> >>>
> >>> Testing: No testsuite regression when targeting arm-none-eabi Armv6S-M.
> >>> Fails as expected when targeting Armv6-M with an -mfpu or a default FPU.
> >>> Succeeds without.
> >>>
> >>> Is this ok for stage3?
> >>>
> >>> Best regards,
> >>>
> >>> Thomas
> >>> ---
> >>>  gcc/config/arm/arm.c                         | 3 +++
> >>>  gcc/testsuite/gcc.target/arm/thumb1_mfpu-1.c | 7 +++++++
> >>>  gcc/testsuite/gcc.target/arm/thumb1_mfpu-2.c | 8 ++++++++
> >>>  3 files changed, 18 insertions(+)
> >>>  create mode 100644 gcc/testsuite/gcc.target/arm/thumb1_mfpu-1.c
> >>>  create mode 100644 gcc/testsuite/gcc.target/arm/thumb1_mfpu-2.c
> >>>
> >>> diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
> >>> index 40f0574e32e..1a205123cf5 100644
> >>> --- a/gcc/config/arm/arm.c
> >>> +++ b/gcc/config/arm/arm.c
> >>> @@ -3747,6 +3747,9 @@ arm_options_perform_arch_sanity_checks (void)
> >>>      {
> >>>        if (arm_abi == ARM_ABI_IWMMXT)
> >>>       arm_pcs_default = ARM_PCS_AAPCS_IWMMXT;
> >>> +      else if (TARGET_THUMB1
> >>> +            && bitmap_bit_p (arm_active_target.isa, isa_bit_vfpv2))
> >>> +     error ("Thumb-1 does not allow FP instructions");
> >>>        else if (TARGET_HARD_FLOAT_ABI)
> >>>       {
> >>>         arm_pcs_default = ARM_PCS_AAPCS_VFP;
> >>> diff --git a/gcc/testsuite/gcc.target/arm/thumb1_mfpu-1.c b/gcc/testsuite/gcc.target/arm/thumb1_mfpu-1.c
> >>> new file mode 100644
> >>> index 00000000000..5347e63f9b6
> >>> --- /dev/null
> >>> +++ b/gcc/testsuite/gcc.target/arm/thumb1_mfpu-1.c
> >>> @@ -0,0 +1,7 @@
> >>> +/* { dg-do compile } */
> >>> +/* { dg-require-effective-target arm_thumb1_ok } */
> >>> +/* { dg-skip-if "incompatible float ABI" { *-*-* } { "-mfloat-abi=*" } { "-mfloat-abi=softfp" } } */
> >>> +/* { dg-options "-mthumb -mfpu=vfp -mfloat-abi=softfp" } */
> >>> +/* { dg-error "Thumb-1 does not allow FP instructions" "" { target *-*-* } 0 } */
> >>> +
> >>> +int foo;
> >>> diff --git a/gcc/testsuite/gcc.target/arm/thumb1_mfpu-2.c b/gcc/testsuite/gcc.target/arm/thumb1_mfpu-2.c
> >>> new file mode 100644
> >>> index 00000000000..941ed26ed01
> >>> --- /dev/null
> >>> +++ b/gcc/testsuite/gcc.target/arm/thumb1_mfpu-2.c
> >>> @@ -0,0 +1,8 @@
> >>> +/* { dg-do compile } */
> >>> +/* { dg-require-effective-target arm_thumb1_ok } */
> >>> +/* { dg-skip-if "incompatible float ABI" { *-*-* } { "-mfloat-abi=*" } { "-mfloat-abi=softfp" } } */
> >>> +/* No need to skip in presence of -mfpu since arm_thumb1_ok will already fail
> >>> +   due to Thumb-1 with -mfpu which is tested by thumb1_mfpu-1 testcase.  */
> >>> +/* { dg-options "-mthumb -mfloat-abi=softfp" } */
> >>> +
> >>> +int foo;
> >>>
> >>
> >>
> >> softfloat_mfpu_set_softfp_thumb1.patch
> >>
> >> From 7c056f386df458f08c0ae367edc7050d53cd6602 Mon Sep 17 00:00:00 2001
> >> From: Thomas Preud'homme <thomas.preudhomme@linaro.org>
> >> Date: Tue, 27 Nov 2018 15:52:38 +0000
> >> Subject: [PATCH] [PATCH, ARM] Do softfloat when -mfpu set, -mfloat-abi=softfp
> >>  and targeting Thumb-1
> >>
> >> Hi,
> >>
> >> FP instructions are only enabled for TARGET_32BIT and TARGET_HARD_FLOAT
> >> but GCC only gives an error when TARGET_HARD_FLOAT is true and -mfpu is
> >> not set. Among other things, it makes some of the cmse tests (eg.
> >> gcc.target/arm/cmse/baseline/softfp.c) fail when targeting
> >> -march=armv8-m.base -mcmse -mfpu=<something> -mfloat-abi=softfp. This
> >> patch adds an extra check for TARGET_32BIT to TARGET_HARD_FLOAT such
> >> that it is false on TARGET_THUMB1 targets even when a FPU is specified.
> >>
> >> ChangeLog entries are as follows:
> >>
> >> *** gcc/ChangeLog ***
> >>
> >> 2018-12-14  thomas Preud'homme  <thomas.preudhomme@linaro.org>
> >>
> >>      * config/arm/arm.h (TARGET_HARD_FLOAT): Restrict to TARGET_32BIT
> >>      targets.
> >>
> >> *** gcc/testsuite/ChangeLog ***
> >>
> >> 2018-12-14  thomas Preud'homme  <thomas.preudhomme@linaro.org>
> >>
> >>      * gcc.target/arm/cmse/baseline/softfp.c: Force an FPU.
> >>
> >> Testing: No testsuite regression when targeting arm-none-eabi Armv6S-M.
> >>
> >> Is this ok for stage3?
> >>
> >> Best regards,
> >>
> >> Thomas
> >> ---
> >>  gcc/config/arm/arm.h                                | 3 ++-
> >>  gcc/testsuite/gcc.target/arm/cmse/baseline/softfp.c | 4 +++-
> >>  2 files changed, 5 insertions(+), 2 deletions(-)
> >>
> >> diff --git a/gcc/config/arm/arm.h b/gcc/config/arm/arm.h
> >> index 8472312487b..149243d0978 100644
> >> --- a/gcc/config/arm/arm.h
> >> +++ b/gcc/config/arm/arm.h
> >> @@ -125,7 +125,8 @@ extern tree arm_fp16_type_node;
> >>  /* Use hardware floating point instructions. */
> >>  #define TARGET_HARD_FLOAT   (arm_float_abi != ARM_FLOAT_ABI_SOFT    \
> >>                               && bitmap_bit_p (arm_active_target.isa, \
> >> -                                              isa_bit_vfpv2))
> >> +                                              isa_bit_vfpv2) \
> >> +                             && TARGET_32BIT)
> >>  #define TARGET_SOFT_FLOAT   (!TARGET_HARD_FLOAT)
> >>  /* User has permitted use of FP instructions, if they exist for this
> >>     target.  */
> >> diff --git a/gcc/testsuite/gcc.target/arm/cmse/baseline/softfp.c b/gcc/testsuite/gcc.target/arm/cmse/baseline/softfp.c
> >> index 3d383ff6ee1..30b3eec078c 100644
> >> --- a/gcc/testsuite/gcc.target/arm/cmse/baseline/softfp.c
> >> +++ b/gcc/testsuite/gcc.target/arm/cmse/baseline/softfp.c
> >> @@ -1,5 +1,7 @@
> >>  /* { dg-do compile } */
> >> -/* { dg-options "-mcmse -mfloat-abi=softfp" } */
> >> +/* Force an FPU to test that it is ignored for Thumb-1 -like targets and that
> >> +   no clearing of VFP register occurs.  */
> >> +/* { dg-options "-mcmse -mfloat-abi=softfp -mfpu=fpv5-d16" } */
> >>
> >>  double __attribute__ ((cmse_nonsecure_call)) (*bar) (float, double);
> >>
>

[-- Attachment #2: softfloat_mfpu_set_softfp_thumb1.patch --]
[-- Type: text/x-patch, Size: 3356 bytes --]

From ca495cecf39eabe761eb073dbbe844118a98229d Mon Sep 17 00:00:00 2001
From: Thomas Preud'homme <thomas.preudhomme@linaro.org>
Date: Tue, 27 Nov 2018 15:52:38 +0000
Subject: [PATCH] [PATCH, ARM] Do softfloat when -mfpu set, -mfloat-abi=softfp
 and targeting Thumb-1

Hi,

FP instructions are only enabled for TARGET_32BIT and TARGET_HARD_FLOAT
but GCC only gives an error when TARGET_HARD_FLOAT is true and -mfpu is
not set. Among other things, it makes some of the cmse tests (eg.
gcc.target/arm/cmse/baseline/softfp.c) fail when targeting
-march=armv8-m.base -mcmse -mfpu=<something> -mfloat-abi=softfp. This
patch adds an extra check for TARGET_32BIT to TARGET_HARD_FLOAT such
that it is false on TARGET_THUMB1 targets even when a FPU is specified.

ChangeLog entries are as follows:

*** gcc/ChangeLog ***

2018-12-19  thomas Preud'homme  <thomas.preudhomme@linaro.org>

	* config/arm/arm.h (TARGET_HARD_FLOAT): Restrict to TARGET_32BIT
	targets.
	* config/arm/arm.c (output_return_instruction): Only check
	TARGET_HARD_FLOAT to decide whether FP instructions are available.

*** gcc/testsuite/ChangeLog ***

2018-12-14  thomas Preud'homme  <thomas.preudhomme@linaro.org>

	* gcc.target/arm/cmse/baseline/softfp.c: Force an FPU.

Testing: No testsuite regression when targeting arm-none-eabi Armv6S-M.

Is this ok for stage3?

Best regards,

Thomas
---
 gcc/config/arm/arm.c                                | 2 +-
 gcc/config/arm/arm.h                                | 3 ++-
 gcc/testsuite/gcc.target/arm/cmse/baseline/softfp.c | 4 +++-
 3 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
index 40f0574e32e..509f287aa63 100644
--- a/gcc/config/arm/arm.c
+++ b/gcc/config/arm/arm.c
@@ -19872,7 +19872,7 @@ output_return_instruction (rtx operand, bool really_return, bool reverse,
 			  "msr%s\tAPSR_nzcvq, %%|lr", conditional);
 
 	      output_asm_insn (instr, & operand);
-	      if (TARGET_HARD_FLOAT && !TARGET_THUMB1)
+	      if (TARGET_HARD_FLOAT)
 		{
 		  /* Clear the cumulative exception-status bits (0-4,7) and the
 		     condition code bits (28-31) of the FPSCR.  We need to
diff --git a/gcc/config/arm/arm.h b/gcc/config/arm/arm.h
index 8472312487b..149243d0978 100644
--- a/gcc/config/arm/arm.h
+++ b/gcc/config/arm/arm.h
@@ -125,7 +125,8 @@ extern tree arm_fp16_type_node;
 /* Use hardware floating point instructions. */
 #define TARGET_HARD_FLOAT	(arm_float_abi != ARM_FLOAT_ABI_SOFT	\
 				 && bitmap_bit_p (arm_active_target.isa, \
-						  isa_bit_vfpv2))
+						  isa_bit_vfpv2) \
+				 && TARGET_32BIT)
 #define TARGET_SOFT_FLOAT	(!TARGET_HARD_FLOAT)
 /* User has permitted use of FP instructions, if they exist for this
    target.  */
diff --git a/gcc/testsuite/gcc.target/arm/cmse/baseline/softfp.c b/gcc/testsuite/gcc.target/arm/cmse/baseline/softfp.c
index 3d383ff6ee1..30b3eec078c 100644
--- a/gcc/testsuite/gcc.target/arm/cmse/baseline/softfp.c
+++ b/gcc/testsuite/gcc.target/arm/cmse/baseline/softfp.c
@@ -1,5 +1,7 @@
 /* { dg-do compile } */
-/* { dg-options "-mcmse -mfloat-abi=softfp" } */
+/* Force an FPU to test that it is ignored for Thumb-1 -like targets and that
+   no clearing of VFP register occurs.  */
+/* { dg-options "-mcmse -mfloat-abi=softfp -mfpu=fpv5-d16" } */
 
 double __attribute__ ((cmse_nonsecure_call)) (*bar) (float, double);
 
-- 
2.19.1


^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2018-12-19 15:03 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-11-29 10:51 [PATCH, ARM] Error out when -mfpu set and targeting Thumb-1 Thomas Preudhomme
2018-11-29 14:52 ` Richard Earnshaw (lists)
2018-12-14 21:16   ` [PATCH, ARM] Do softfloat when -mfpu set, -mfloat-abi=softfp " Thomas Preudhomme
2018-12-19 14:13     ` Richard Earnshaw (lists)
2018-12-19 15:03       ` Thomas Preudhomme

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