[gcc r14-11644] aarch64: Disable sysreg feature gating

2025-04-16 Thread Alice Carlotti via Gcc-cvs 
https://gcc.gnu.org/g:c344377bb3e7aefa617f501707473246d0d96ad8

commit r14-11644-gc344377bb3e7aefa617f501707473246d0d96ad8
Author: Alice Carlotti 
Date:   Tue Apr 15 17:36:25 2025 +0100

aarch64: Disable sysreg feature gating

This applies to the sysreg read/write intrinsics __arm_[wr]sr*.  It does
not depend on changes to Binutils, because GCC converts recognised
sysreg names to an encoding based form, which is already ungated in 
Binutils.

We have, however, agreed to make an equivalent change in Binutils (which
would then disable feature gating for sysreg accesses in inline
assembly), but this has not yet been posted upstream.

In the future we may introduce a new flag to renable some checking,
but these checks could not be comprehensive because many system
registers depend on architecture features that don't have corresponding
GCC/GAS --march options.  This would also depend on addressing numerous
inconsistencies in the existing list of sysreg feature dependencies.

gcc/ChangeLog:

* config/aarch64/aarch64.cc
(aarch64_valid_sysreg_name_p): Remove feature check.
(aarch64_retrieve_sysreg): Ditto.

gcc/testsuite/ChangeLog:

* gcc.target/aarch64/acle/rwsr-ungated.c: New test.

Diff:
---
 gcc/config/aarch64/aarch64.cc|  4 
 gcc/testsuite/gcc.target/aarch64/acle/rwsr-ungated.c | 13 +
 2 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/gcc/config/aarch64/aarch64.cc b/gcc/config/aarch64/aarch64.cc
index 2c34a58f56a6..fa721c1221e7 100644
--- a/gcc/config/aarch64/aarch64.cc
+++ b/gcc/config/aarch64/aarch64.cc
@@ -30344,8 +30344,6 @@ aarch64_valid_sysreg_name_p (const char *regname)
   const sysreg_t *sysreg = aarch64_lookup_sysreg_map (regname);
   if (sysreg == NULL)
 return aarch64_is_implem_def_reg (regname);
-  if (sysreg->arch_reqs)
-return (aarch64_isa_flags & sysreg->arch_reqs);
   return true;
 }
 
@@ -30369,8 +30367,6 @@ aarch64_retrieve_sysreg (const char *regname, bool 
write_p, bool is128op)
   if ((write_p && (sysreg->properties & F_REG_READ))
   || (!write_p && (sysreg->properties & F_REG_WRITE)))
 return NULL;
-  if ((~aarch64_isa_flags & sysreg->arch_reqs) != 0)
-return NULL;
   return sysreg->encoding;
 }
 
diff --git a/gcc/testsuite/gcc.target/aarch64/acle/rwsr-ungated.c 
b/gcc/testsuite/gcc.target/aarch64/acle/rwsr-ungated.c
new file mode 100644
index ..d67a42673733
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/acle/rwsr-ungated.c
@@ -0,0 +1,13 @@
+/* Test that __arm_[r,w]sr intrinsics aren't gated (by default).  */
+
+/* { dg-do compile } */
+/* { dg-options "-march=armv8-a" } */
+
+#include 
+
+uint64_t
+foo (uint64_t a)
+{
+  __arm_wsr64 ("zcr_el1", a);
+  return __arm_rsr64 ("smcr_el1");
+}

[gcc r15-9511] aarch64: Disable sysreg feature gating

2025-04-15 Thread Alice Carlotti via Gcc-cvs 
https://gcc.gnu.org/g:43cbf049f5b017316f6fb1ea5f95784194323a51

commit r15-9511-g43cbf049f5b017316f6fb1ea5f95784194323a51
Author: Alice Carlotti 
Date:   Tue Apr 15 17:36:25 2025 +0100

aarch64: Disable sysreg feature gating

This applies to the sysreg read/write intrinsics __arm_[wr]sr*.  It does
not depend on changes to Binutils, because GCC converts recognised
sysreg names to an encoding based form, which is already ungated in 
Binutils.

We have, however, agreed to make an equivalent change in Binutils (which
would then disable feature gating for sysreg accesses in inline
assembly), but this has not yet been posted upstream.

In the future we may introduce a new flag to renable some checking,
but these checks could not be comprehensive because many system
registers depend on architecture features that don't have corresponding
GCC/GAS --march options.  This would also depend on addressing numerous
inconsistencies in the existing list of sysreg feature dependencies.

gcc/ChangeLog:

* config/aarch64/aarch64.cc
(aarch64_valid_sysreg_name_p): Remove feature check.
(aarch64_retrieve_sysreg): Ditto.

gcc/testsuite/ChangeLog:

* gcc.target/aarch64/acle/rwsr-ungated.c: New test.

Diff:
---
 gcc/config/aarch64/aarch64.cc|  4 
 gcc/testsuite/gcc.target/aarch64/acle/rwsr-ungated.c | 13 +
 2 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/gcc/config/aarch64/aarch64.cc b/gcc/config/aarch64/aarch64.cc
index 4e801146c60a..433ec975d7e4 100644
--- a/gcc/config/aarch64/aarch64.cc
+++ b/gcc/config/aarch64/aarch64.cc
@@ -31073,8 +31073,6 @@ aarch64_valid_sysreg_name_p (const char *regname)
   const sysreg_t *sysreg = aarch64_lookup_sysreg_map (regname);
   if (sysreg == NULL)
 return aarch64_is_implem_def_reg (regname);
-  if (sysreg->arch_reqs)
-return bool (aarch64_isa_flags & sysreg->arch_reqs);
   return true;
 }
 
@@ -31098,8 +31096,6 @@ aarch64_retrieve_sysreg (const char *regname, bool 
write_p, bool is128op)
   if ((write_p && (sysreg->properties & F_REG_READ))
   || (!write_p && (sysreg->properties & F_REG_WRITE)))
 return NULL;
-  if ((~aarch64_isa_flags & sysreg->arch_reqs) != 0)
-return NULL;
   return sysreg->encoding;
 }
 
diff --git a/gcc/testsuite/gcc.target/aarch64/acle/rwsr-ungated.c 
b/gcc/testsuite/gcc.target/aarch64/acle/rwsr-ungated.c
new file mode 100644
index ..d67a42673733
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/acle/rwsr-ungated.c
@@ -0,0 +1,13 @@
+/* Test that __arm_[r,w]sr intrinsics aren't gated (by default).  */
+
+/* { dg-do compile } */
+/* { dg-options "-march=armv8-a" } */
+
+#include 
+
+uint64_t
+foo (uint64_t a)
+{
+  __arm_wsr64 ("zcr_el1", a);
+  return __arm_rsr64 ("smcr_el1");
+}