[PATCH v2] rs6000: Fix issue in specifying PTImode as an attribute [PR106895]

[jeevitha <jeevitha@linux.ibm.com>]

Hi All,

The following patch has been bootstrapped and regtested on powerpc64le-linux.

PTImode assists in generating even/odd register pairs on 128 bits. When the user 
specifies PTImode as an attribute, it breaks because there is no internal type 
to handle this mode. To address this, we have created a tree node with dummy type
to handle PTImode. We are not documenting this dummy type since users are not
allowed to use this type externally.

2024-03-21  Jeevitha Palanisamy  <jeevitha@linux.ibm.com>

gcc/
	PR target/110411
	* config/rs6000/rs6000.h (enum rs6000_builtin_type_index): Add
	RS6000_BTI_INTPTI.
	* config/rs6000/rs6000-builtin.cc (rs6000_init_builtins): Add node
	for PTImode type.

gcc/testsuite/
	PR target/106895
	* gcc.target/powerpc/pr106895.c: New testcase.

diff --git a/gcc/config/rs6000/rs6000-builtin.cc b/gcc/config/rs6000/rs6000-builtin.cc
index 6698274031b..f553c72779e 100644
--- a/gcc/config/rs6000/rs6000-builtin.cc
+++ b/gcc/config/rs6000/rs6000-builtin.cc
@@ -756,6 +756,15 @@ rs6000_init_builtins (void)
   else
     ieee128_float_type_node = NULL_TREE;
 
+  /* PTImode to get even/odd register pairs.  */
+  intPTI_type_internal_node = make_node(INTEGER_TYPE);
+  TYPE_PRECISION (intPTI_type_internal_node) = GET_MODE_BITSIZE (PTImode);
+  layout_type (intPTI_type_internal_node);
+  SET_TYPE_MODE (intPTI_type_internal_node, PTImode);
+  t = build_qualified_type (intPTI_type_internal_node, TYPE_QUAL_CONST);
+  lang_hooks.types.register_builtin_type (intPTI_type_internal_node,
+					  "__dummypti");
+
   /* Vector pair and vector quad support.  */
   vector_pair_type_node = make_node (OPAQUE_TYPE);
   SET_TYPE_MODE (vector_pair_type_node, OOmode);
diff --git a/gcc/config/rs6000/rs6000.h b/gcc/config/rs6000/rs6000.h
index 68bc45d65ba..b6078077b20 100644
--- a/gcc/config/rs6000/rs6000.h
+++ b/gcc/config/rs6000/rs6000.h
@@ -2302,6 +2302,7 @@ enum rs6000_builtin_type_index
   RS6000_BTI_ptr_vector_quad,
   RS6000_BTI_ptr_long_long,
   RS6000_BTI_ptr_long_long_unsigned,
+  RS6000_BTI_INTPTI,
   RS6000_BTI_MAX
 };
 
@@ -2346,6 +2347,7 @@ enum rs6000_builtin_type_index
 #define uintDI_type_internal_node	 (rs6000_builtin_types[RS6000_BTI_UINTDI])
 #define intTI_type_internal_node	 (rs6000_builtin_types[RS6000_BTI_INTTI])
 #define uintTI_type_internal_node	 (rs6000_builtin_types[RS6000_BTI_UINTTI])
+#define intPTI_type_internal_node	 (rs6000_builtin_types[RS6000_BTI_INTPTI])
 #define float_type_internal_node	 (rs6000_builtin_types[RS6000_BTI_float])
 #define double_type_internal_node	 (rs6000_builtin_types[RS6000_BTI_double])
 #define long_double_type_internal_node	 (rs6000_builtin_types[RS6000_BTI_long_double])
diff --git a/gcc/testsuite/gcc.target/powerpc/pr106895.c b/gcc/testsuite/gcc.target/powerpc/pr106895.c
new file mode 100644
index 00000000000..56547b7fa9d
--- /dev/null
+++ b/gcc/testsuite/gcc.target/powerpc/pr106895.c
@@ -0,0 +1,15 @@
+/* PR target/106895 */
+/* { dg-require-effective-target int128 } */
+/* { dg-options "-O2" } */
+
+/* Verify the following generates even/odd register pairs.  */
+
+typedef __int128 pti __attribute__((mode(PTI)));
+
+void
+set128 (pti val, pti *mem)
+{
+    asm("stq %1,%0" : "=m"(*mem) : "r"(val));
+}
+
+/* { dg-final { scan-assembler "stq \[123\]?\[02468\]" } } */