[PATCH] aarch64: Fix __builtin_apply with -mgeneral-regs-only [PR113486]

[PATCH] aarch64: Fix __builtin_apply with -mgeneral-regs-only [PR113486]

[Andrew Pinski]

The problem here is the builtin apply mechanism thinks the FP registers
are to be used due to get_raw_arg_mode not returning VOIDmode. This
fixes that oversight and the backend now returns VOIDmode for non-general-regs
if TARGET_GENERAL_REGS_ONLY is true.

Built and tested for aarch64-linux-gnu with no regressions.

	PR target/113486

gcc/ChangeLog:

	* config/aarch64/aarch64.cc (aarch64_get_reg_raw_mode): For
	TARGET_GENERAL_REGS_ONLY, return VOIDmode for non-GP_REGNUM_P regno.

gcc/testsuite/ChangeLog:

	* gcc.target/aarch64/builtin_apply-1.c: New test.

Signed-off-by: Andrew Pinski <quic_apinski@quicinc.com>
---
 gcc/config/aarch64/aarch64.cc                      |  4 ++++
 gcc/testsuite/gcc.target/aarch64/builtin_apply-1.c | 12 ++++++++++++
 2 files changed, 16 insertions(+)
 create mode 100644 gcc/testsuite/gcc.target/aarch64/builtin_apply-1.c

diff --git a/gcc/config/aarch64/aarch64.cc b/gcc/config/aarch64/aarch64.cc
index e6bd3fd0bb4..a838cbba51d 100644
--- a/gcc/config/aarch64/aarch64.cc
+++ b/gcc/config/aarch64/aarch64.cc
@@ -7221,6 +7221,10 @@ aarch64_function_arg_boundary (machine_mode mode, const_tree type)
 static fixed_size_mode
 aarch64_get_reg_raw_mode (int regno)
 {
+  /* Don't use any non GP registers for __builtin_apply and
+     __builtin_return if general registers only mode is requested. */
+  if (TARGET_GENERAL_REGS_ONLY && !GP_REGNUM_P (regno))
+    return as_a <fixed_size_mode> (VOIDmode);
   if (TARGET_SVE && FP_REGNUM_P (regno))
     /* Don't use the SVE part of the register for __builtin_apply and
        __builtin_return.  The SVE registers aren't used by the normal PCS,
diff --git a/gcc/testsuite/gcc.target/aarch64/builtin_apply-1.c b/gcc/testsuite/gcc.target/aarch64/builtin_apply-1.c
new file mode 100644
index 00000000000..d70abe037d2
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/builtin_apply-1.c
@@ -0,0 +1,12 @@
+/* { dg-do compile } */
+/* { dg-options "-mgeneral-regs-only" } */
+/* PR target/113486 */
+
+
+/* __builtin_apply should not use FP registers if 
+   general registers only mode is requested. */
+void
+foo (void)
+{
+  __builtin_apply (foo, 0, 0);
+}
-- 
2.39.3

Re: [PATCH] aarch64: Fix __builtin_apply with -mgeneral-regs-only [PR113486]

[Richard Sandiford]

Andrew Pinski <quic_apinski@quicinc.com> writes:
> The problem here is the builtin apply mechanism thinks the FP registers
> are to be used due to get_raw_arg_mode not returning VOIDmode. This
> fixes that oversight and the backend now returns VOIDmode for non-general-regs
> if TARGET_GENERAL_REGS_ONLY is true.
>
> Built and tested for aarch64-linux-gnu with no regressions.
>
> 	PR target/113486
>
> gcc/ChangeLog:
>
> 	* config/aarch64/aarch64.cc (aarch64_get_reg_raw_mode): For
> 	TARGET_GENERAL_REGS_ONLY, return VOIDmode for non-GP_REGNUM_P regno.
>
> gcc/testsuite/ChangeLog:
>
> 	* gcc.target/aarch64/builtin_apply-1.c: New test.

OK, thanks.

Richard

> Signed-off-by: Andrew Pinski <quic_apinski@quicinc.com>
> ---
>  gcc/config/aarch64/aarch64.cc                      |  4 ++++
>  gcc/testsuite/gcc.target/aarch64/builtin_apply-1.c | 12 ++++++++++++
>  2 files changed, 16 insertions(+)
>  create mode 100644 gcc/testsuite/gcc.target/aarch64/builtin_apply-1.c
>
> diff --git a/gcc/config/aarch64/aarch64.cc b/gcc/config/aarch64/aarch64.cc
> index e6bd3fd0bb4..a838cbba51d 100644
> --- a/gcc/config/aarch64/aarch64.cc
> +++ b/gcc/config/aarch64/aarch64.cc
> @@ -7221,6 +7221,10 @@ aarch64_function_arg_boundary (machine_mode mode, const_tree type)
>  static fixed_size_mode
>  aarch64_get_reg_raw_mode (int regno)
>  {
> +  /* Don't use any non GP registers for __builtin_apply and
> +     __builtin_return if general registers only mode is requested. */
> +  if (TARGET_GENERAL_REGS_ONLY && !GP_REGNUM_P (regno))
> +    return as_a <fixed_size_mode> (VOIDmode);
>    if (TARGET_SVE && FP_REGNUM_P (regno))
>      /* Don't use the SVE part of the register for __builtin_apply and
>         __builtin_return.  The SVE registers aren't used by the normal PCS,
> diff --git a/gcc/testsuite/gcc.target/aarch64/builtin_apply-1.c b/gcc/testsuite/gcc.target/aarch64/builtin_apply-1.c
> new file mode 100644
> index 00000000000..d70abe037d2
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/aarch64/builtin_apply-1.c
> @@ -0,0 +1,12 @@
> +/* { dg-do compile } */
> +/* { dg-options "-mgeneral-regs-only" } */
> +/* PR target/113486 */
> +
> +
> +/* __builtin_apply should not use FP registers if 
> +   general registers only mode is requested. */
> +void
> +foo (void)
> +{
> +  __builtin_apply (foo, 0, 0);
> +}