[PATCH] AArch64: Add ACLE MOPS support

[Wilco Dijkstra]

Add __ARM_FEATURE_MOPS predefine.  Add support for ACLE __arm_mops_memset_tag.

Passes regress, OK for commit?

gcc:
        * config/aaarch64/aarch64-c.cc (aarch64_update_cpp_builtins):
        Add __ARM_FEATURE_MOPS predefine.
        * config/aarch64/arm_acle.h: Add __arm_mops_memset_tag().

gcc/testsuite:
        * gcc.target/aarch64/acle/memtag_5.c: Add new test.

---

diff --git a/gcc/config/aarch64/aarch64-c.cc b/gcc/config/aarch64/aarch64-c.cc
index 
fe1a20e4e546a68e5f7eddff3bbb0d3e831fbd9b..884a7ba5d10b58fbe182a765041cf80bdaec9615
 100644
--- a/gcc/config/aarch64/aarch64-c.cc
+++ b/gcc/config/aarch64/aarch64-c.cc
@@ -260,6 +260,7 @@ aarch64_update_cpp_builtins (cpp_reader *pfile)
   aarch64_def_or_undef (TARGET_SME_I16I64, "__ARM_FEATURE_SME_I16I64", pfile);
   aarch64_def_or_undef (TARGET_SME_F64F64, "__ARM_FEATURE_SME_F64F64", pfile);
   aarch64_def_or_undef (TARGET_SME2, "__ARM_FEATURE_SME2", pfile);
+  aarch64_def_or_undef (TARGET_MOPS, "__ARM_FEATURE_MOPS", pfile);
 
   /* Not for ACLE, but required to keep "float.h" correct if we switch
      target between implementations that do or do not support ARMv8.2-A
diff --git a/gcc/config/aarch64/arm_acle.h b/gcc/config/aarch64/arm_acle.h
index 
2aa681090fa205449cf1ac63151565f960716189..22ee4b211a55ca6537a1d9e3bf4dad09585071fb
 100644
--- a/gcc/config/aarch64/arm_acle.h
+++ b/gcc/config/aarch64/arm_acle.h
@@ -344,6 +344,21 @@ __rndrrs (uint64_t *__res)
 
 #pragma GCC pop_options
 
+#if defined (__ARM_FEATURE_MOPS) && defined (__ARM_FEATURE_MEMORY_TAGGING)
+__extension__ extern __inline void *
+__attribute__ ((__always_inline__, __gnu_inline__, __artificial__))
+__arm_mops_memset_tag (void *__ptr, int __val, size_t __size)
+{
+  void *__ptr2 = __ptr;
+  __asm volatile ("setgp\t[%0]!, %1!, %x2\n\t"
+                 "setgm\t[%0]!, %1!, %x2\n\t"
+                 "setge\t[%0]!, %1!, %x2"
+                 : "+r" (__ptr2), "+r" (__size)
+                 : "rZ" (__val) : "cc", "memory");
+  return __ptr;
+}
+#endif
+
 #define __arm_rsr(__regname) \
   __builtin_aarch64_rsr (__regname)
 
diff --git a/gcc/testsuite/gcc.target/aarch64/acle/memtag_5.c 
b/gcc/testsuite/gcc.target/aarch64/acle/memtag_5.c
new file mode 100644
index 
0000000000000000000000000000000000000000..79ba1eb39d7c6d577fbe98a3285f8cc618428823
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/acle/memtag_5.c
@@ -0,0 +1,22 @@
+/* { dg-do compile } */
+/* { dg-options "-march=armv8.8-a+memtag -O2" } */
+/* { dg-final { check-function-bodies "**" "" "" { target lp64 } } } */
+
+#include "arm_acle.h"
+
+#ifndef __ARM_FEATURE_MOPS
+# error __ARM_FEATURE_MOPS not defined!
+#endif
+
+/*
+** set_tag:
+**     mov     (x[0-9]+), x0
+**     setgp   \[\1\]\!, x1\!, xzr
+**     setgm   \[\1\]\!, x1\!, xzr
+**     setge   \[\1\]\!, x1\!, xzr
+**     ret
+*/
+void *set_tag (void *p, size_t size)
+{
+  return __arm_mops_memset_tag (p, 0, size);
+}