automatic import of gccopeneuler24.03_LTS_SP1

1 files changed, 70 insertions, 0 deletions

diff --git a/0219-Backport-SME-libgcc-aarch64-Add-SME-unwinder-support.patch b/0219-Backport-SME-libgcc-aarch64-Add-SME-unwinder-support.patch
new file mode 100644
index 0000000..91c5d4b
--- /dev/null
+++ b/0219-Backport-SME-libgcc-aarch64-Add-SME-unwinder-support.patch
@@ -0,0 +1,70 @@
+From 310c8b5aaedad1430146fed9d8992201278164a6 Mon Sep 17 00:00:00 2001
+From: Szabolcs Nagy <szabolcs.nagy@arm.com>
+Date: Fri, 29 Sep 2023 13:55:51 +0100
+Subject: [PATCH 120/157] [Backport][SME] libgcc: aarch64: Add SME unwinder
+ support
+
+Reference: https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=91d68665b8b7a5dffd0bbf8cd1f74c3c41d4c2d8
+
+To support the ZA lazy save scheme, the PCS requires the unwinder to
+reset the SME state to PSTATE.SM=0, PSTATE.ZA=0, TPIDR2_EL0=0 on entry
+to an exception handler. We use the __arm_za_disable SME runtime call
+unconditionally to achieve this.
+https://github.com/ARM-software/abi-aa/blob/main/aapcs64/aapcs64.rst#exceptions
+
+The hidden alias is used to avoid a PLT and avoid inconsistent VPCS
+marking (we don't rely on special PCS at the call site). In case of
+static linking the SME runtime init code is linked in code that raises
+exceptions.
+
+libgcc/ChangeLog:
+
+	* config/aarch64/__arm_za_disable.S: Add hidden alias.
+	* config/aarch64/aarch64-unwind.h: Reset the SME state before
+	EH return via the _Unwind_Frames_Extra hook.
+---
+ libgcc/config/aarch64/__arm_za_disable.S |  5 +++++
+ libgcc/config/aarch64/aarch64-unwind.h   | 16 ++++++++++++++++
+ 2 files changed, 21 insertions(+)
+
+diff --git a/libgcc/config/aarch64/__arm_za_disable.S b/libgcc/config/aarch64/__arm_za_disable.S
+index cff5b9cec..03fc28a39 100644
+--- a/libgcc/config/aarch64/__arm_za_disable.S
++++ b/libgcc/config/aarch64/__arm_za_disable.S
+@@ -63,3 +63,8 @@ ENTRY (__arm_za_disable)
+ L(end):
+ 	ret
+ END (__arm_za_disable)
++
++/* Hidden alias used by the unwinder.  */
++.global __libgcc_arm_za_disable
++.hidden __libgcc_arm_za_disable
++.set __libgcc_arm_za_disable, __arm_za_disable
+diff --git a/libgcc/config/aarch64/aarch64-unwind.h b/libgcc/config/aarch64/aarch64-unwind.h
+index 40b22d3c2..bfa695dcb 100644
+--- a/libgcc/config/aarch64/aarch64-unwind.h
++++ b/libgcc/config/aarch64/aarch64-unwind.h
+@@ -87,4 +87,20 @@ aarch64_frob_update_context (struct _Unwind_Context *context,
+   return;
+ }
+ 
++/* SME runtime function local to libgcc, streaming compatible
++   and preserves more registers than the base PCS requires, but
++   we don't rely on that here.  */
++__attribute__ ((visibility ("hidden")))
++void __libgcc_arm_za_disable (void);
++
++/* Disable the SME ZA state in case an unwound frame used the ZA
++   lazy saving scheme.  */
++#undef _Unwind_Frames_Extra
++#define _Unwind_Frames_Extra(x)				\
++  do							\
++    {							\
++      __libgcc_arm_za_disable ();			\
++    }							\
++  while (0)
++
+ #endif /* defined AARCH64_UNWIND_H && defined __ILP32__ */
+-- 
+2.33.0
+