From 5ec7740496a6908b32cd058c0520a2bd5a689bb5 Mon Sep 17 00:00:00 2001
From: Andrew Pinski <quic_apinski@quicinc.com>
Date: Wed, 28 Feb 2024 22:39:32 -0800
Subject: [PATCH] aarch64: Fix memtag builtins vs GC [PR108174]

The memtag builtins were being GC'ed away so we end up
with a crash sometimes (maybe even wrong code).
This fixes that issue by adding GTY on the variable/struct
aarch64_memtag_builtin_data.

Committed as obvious after a build/test for aarch64-linux-gnu.

	PR target/108174

gcc/ChangeLog:

	* config/aarch64/aarch64-builtins.cc (aarch64_memtag_builtin_data): Make
	static and mark with GTY.

gcc/testsuite/ChangeLog:

	* gcc.target/aarch64/acle/memtag_4.c: New test.

Signed-off-by: Andrew Pinski <quic_apinski@quicinc.com>
---
 gcc/config/aarch64/aarch64-builtins.cc           |  2 +-
 gcc/testsuite/gcc.target/aarch64/acle/memtag_4.c | 16 ++++++++++++++++
 2 files changed, 17 insertions(+), 1 deletion(-)
 create mode 100644 gcc/testsuite/gcc.target/aarch64/acle/memtag_4.c

diff --git a/gcc/config/aarch64/aarch64-builtins.cc b/gcc/config/aarch64/aarch64-builtins.cc
index 277904f6d142..75d21de14011 100644
--- a/gcc/config/aarch64/aarch64-builtins.cc
+++ b/gcc/config/aarch64/aarch64-builtins.cc
@@ -1840,7 +1840,7 @@ aarch64_init_prefetch_builtin (void)
 }
 
 /* Initialize the memory tagging extension (MTE) builtins.  */
-struct
+static GTY(()) struct GTY(())
 {
   tree ftype;
   enum insn_code icode;
diff --git a/gcc/testsuite/gcc.target/aarch64/acle/memtag_4.c b/gcc/testsuite/gcc.target/aarch64/acle/memtag_4.c
new file mode 100644
index 000000000000..1e209ffc25a8
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/acle/memtag_4.c
@@ -0,0 +1,16 @@
+/* { dg-do compile } */
+/* { dg-options "-march=armv9-a+memtag  --param ggc-min-expand=0 --param ggc-min-heapsize=0" } */
+/* PR target/108174 */
+/* Check to make sure that the builtin functions are not GC'ed away. */
+#include "arm_acle.h"
+
+void g(void)
+{
+  const char *c;
+  __arm_mte_increment_tag(c , 0 );
+}
+void h(void)
+{
+  const char *c;
+  __arm_mte_increment_tag( c,0);
+}
-- 
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