[gcc(refs/vendors/ARM/heads/morello)] Testism adjustments for pure capability

[gcc(refs/vendors/ARM/heads/morello)] Testism adjustments for pure capability

[Matthew Malcomson]

https://gcc.gnu.org/g:d6a3de7701325735daac7a49005c978cc28e97da

commit d6a3de7701325735daac7a49005c978cc28e97da
Author: Matthew Malcomson <matthew.malcomson@arm.com>
Date:   Thu Oct 13 12:57:14 2022 +0100

    Testism adjustments for pure capability
    
    array25.C
    This testcase uses a global buffer as its place to allocate a structure.
    During initialisation on unoptimised code, the structure initialises its
    sub-structures with zeros.  Since the sub-structure contains a pointer
    that includes storing a capability.  Said global buffer is not aligned.
    Hence we get a BUS error.
    
    Here we ensure that the alignment is specified for pure capability
    targets.
    
    struct-layout-1.exp
    This testcase generates multiple different structures with different
    alignment behaviours.  It purposefully generates misaligned pointers.
    These cause failures on purecap.
    This is a G++ variation of the same problem that we had in GCC, and we
    simply avoid the tests in the same way that we avoided them in GCC.
    
    g++.abi/vtable2.C
    This testcase uses ptrdiff_t for vtable entries.  On purecap we have
    capability-sized and capability-aligned vtable entries.  There seems to
    be at least one existing target architecture (see gcc/config/darwin.h)
    which uses different types for ptrdiff_t and intptr_t (although I
    haven't checked whether these types boil down to the same size data on
    hardware), so rather than change the testcase for existing architectures
    we only change the type for purecap.

Diff:
---
 gcc/testsuite/g++.dg/compat/struct-layout-1.exp |  5 +++++
 gcc/testsuite/g++.dg/init/array25.C             |  3 +++
 gcc/testsuite/g++.old-deja/g++.abi/vtable2.C    | 16 +++++++++++-----
 3 files changed, 19 insertions(+), 5 deletions(-)

diff --git a/gcc/testsuite/g++.dg/compat/struct-layout-1.exp b/gcc/testsuite/g++.dg/compat/struct-layout-1.exp
index f2a20aafafd..8fc799f794e 100644
--- a/gcc/testsuite/g++.dg/compat/struct-layout-1.exp
+++ b/gcc/testsuite/g++.dg/compat/struct-layout-1.exp
@@ -17,6 +17,11 @@
 # This file was written by Jakub Jelinek, <jakub@redhat.com>
 # Based on compat.exp writte by Janis Johnson, <janis187@us.ibm.com>
 
+# The random generator in this testsuite may deliberately underalign
+# capabilities in a packed struct. This is currently not supported.
+if { [check_effective_target_cheri_capability_pure] } then {
+  return
+}
 
 # Test interoperability of two compilers that follow the same ABI.
 #
diff --git a/gcc/testsuite/g++.dg/init/array25.C b/gcc/testsuite/g++.dg/init/array25.C
index 1ab2725d7cf..f738d2e67c0 100644
--- a/gcc/testsuite/g++.dg/init/array25.C
+++ b/gcc/testsuite/g++.dg/init/array25.C
@@ -33,6 +33,9 @@ inline void *operator new (__SIZE_TYPE__ size, void *p)
   return p;
 }
 
+#ifdef __CHERI_PURE_CAPABILITY__
+__attribute__((aligned(16)))
+#endif
 char heap[sizeof(elt[500])];
 
 int main ()
diff --git a/gcc/testsuite/g++.old-deja/g++.abi/vtable2.C b/gcc/testsuite/g++.old-deja/g++.abi/vtable2.C
index 96533e09218..62fbd76ce20 100644
--- a/gcc/testsuite/g++.old-deja/g++.abi/vtable2.C
+++ b/gcc/testsuite/g++.old-deja/g++.abi/vtable2.C
@@ -6,6 +6,12 @@
 
 #include <stddef.h>
 
+#ifdef __CHERI_PURE_CAPABILITY__
+typedef __INTPTR_TYPE__ vtable_type;
+#else
+typedef ptrdiff_t vtable_type;
+#endif
+
 struct S0
 {
   virtual void s0 ();
@@ -149,14 +155,14 @@ extern "C" {
 #ifdef _LP64
 #define CMP_VPTR(A, B)	(*(unsigned long *)(*(A)+16) == *(unsigned long *)((unsigned long)(B)+16))
 #else
-#define CMP_VPTR(A, B)	(*(A) == (ptrdiff_t)(B))
+#define CMP_VPTR(A, B)	(*(A) == (vtable_type)(B))
 #endif /* _LP64 */
 #else
 extern "C" { unsigned int __canonicalize_funcptr_for_compare (void*); }
 #define CMP_VPTR(A, B) (__canonicalize_funcptr_for_compare(*(void **)A) == __canonicalize_funcptr_for_compare((void *)B))
 #endif /* __hpux__ */
 #else
-#define CMP_VPTR(A, B)	(*(A) == (ptrdiff_t)(B))
+#define CMP_VPTR(A, B)	(*(A) == (vtable_type)(B))
 #endif /* __hppa__ */
 #define INC_VPTR(A)	((A) += 1)
 #define INC_VDATA(A,N)	((A) += (N))
@@ -165,11 +171,11 @@ extern "C" { unsigned int __canonicalize_funcptr_for_compare (void*); }
 int main ()
 {
   S4 s4;
-  ptrdiff_t **vptr;
-  ptrdiff_t *vtbl;
+  vtable_type **vptr;
+  vtable_type *vtbl;
 
   // Set vtbl to point at the beginning of S4's primary vtable.
-  vptr = (ptrdiff_t **) &s4;
+  vptr = (vtable_type **) &s4;
   vtbl = *vptr;
   INC_VDATA (vtbl, -5);