rs6000: Don't ICE when we disassemble an MMA variable [PR101322]

When we expand an MMA disassemble built-in with C++ using a pointer that
is cast to a valid MMA type, the type isn't passed down to the expand
machinery and we end up using the base type of the pointer which leads to
an ICE.  This patch enforces we always use the correct MMA type regardless
of the pointer type being used.

2022-08-31  Peter Bergner  <bergner@linux.ibm.com>

gcc/
	PR target/101322
	* config/rs6000/rs6000-builtin.cc (rs6000_gimple_fold_mma_builtin):
	Enforce the use of a valid MMA pointer type.

gcc/testsuite/
	PR target/101322
	* g++.target/powerpc/pr101322.C: New test.

(cherry picked from commit 2985049049f12b0aa3366ca244d387820385b9e8)

diff --git a/gcc/config/rs6000/rs6000-builtin.cc b/gcc/config/rs6000/rs6000-builtin.cc
index e925ba9fad9cce1c8cfafc91a0773251fa7bc73a..15370e45e656c33ff6336a7c33e00e5e3d2e68c3 100644 (file)
--- a/gcc/config/rs6000/rs6000-builtin.cc
+++ b/gcc/config/rs6000/rs6000-builtin.cc
@@ -1121,7 +1121,12 @@ rs6000_gimple_fold_mma_builtin (gimple_stmt_iterator *gsi,
       unsigned nvec = (fncode == RS6000_BIF_DISASSEMBLE_ACC) ? 4 : 2;
       tree dst_ptr = gimple_call_arg (stmt, 0);
       tree src_ptr = gimple_call_arg (stmt, 1);
-      tree src_type = TREE_TYPE (src_ptr);
+      tree src_type = (fncode == RS6000_BIF_DISASSEMBLE_ACC)
+                     ? build_pointer_type (vector_quad_type_node)
+                     : build_pointer_type (vector_pair_type_node);
+      if (TREE_TYPE (src_ptr) != src_type)
+       src_ptr = build1 (NOP_EXPR, src_type, src_ptr);
+
       tree src = create_tmp_reg_or_ssa_name (TREE_TYPE (src_type));
       gimplify_assign (src, build_simple_mem_ref (src_ptr), &new_seq);
 

diff --git a/gcc/testsuite/g++.target/powerpc/pr101322.C b/gcc/testsuite/g++.target/powerpc/pr101322.C
new file mode 100644 (file)
index 0000000..43eaf3a
--- /dev/null
+++ b/gcc/testsuite/g++.target/powerpc/pr101322.C
@@ -0,0 +1,17 @@
+/* PR target/101322 */
+/* { dg-require-effective-target power10_ok } */
+/* { dg-options "-O2 -mdejagnu-cpu=power10" } */
+
+/* Verify we don't ICE on the following test cases.  */
+
+void
+foo (char *resp, char *vpp)
+{
+  __builtin_vsx_disassemble_pair (resp, (__vector_pair *) vpp);
+}
+
+void
+bar (char *resp, char *vpp)
+{
+  __builtin_mma_disassemble_acc (resp, (__vector_quad *)vpp);
+}