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

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

[Peter Bergner]

I'd like to ping the following patch.

Peter


    https://gcc.gnu.org/pipermail/gcc-patches/2022-August/600451.html


Message-ID: <c7d29335-ac3a-24d4-486e-7755018263bf@linux.ibm.com>

>When we expand an MMA disassemble built-in with C++ using a pointer that
>is casted 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.
>
>This passed bootstrap and regtesting on powerpc64le-linux with no regressions.
>Ok for trunk and backports after some burn-in time?
>
>Peter
>
>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.
>
>diff --git a/gcc/config/rs6000/rs6000-builtin.cc b/gcc/config/rs6000/rs6000-builtin.cc
>index 12afa86854c..e796e74f072 100644
>--- a/gcc/config/rs6000/rs6000-builtin.cc
>+++ b/gcc/config/rs6000/rs6000-builtin.cc
>@@ -1085,7 +1085,12 @@ 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 (TREE_TYPE (src_ptr)) != src_type)
>+	src_ptr = build1 (VIEW_CONVERT_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
>index 00000000000..59e71e8eb89
>--- /dev/null
>+++ b/gcc/testsuite/g++.target/powerpc/pr101322.C
>@@ -0,0 +1,17 @@
>+/* PR target/101322 */
>+/* { dg-options "-O2 -mdejagnu-cpu=power10" } */
>+/* { dg-require-effective-target power10_ok } */
>+
>+/* 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);
>+}