We have
return VIEW_CONVERT_EXPR<U>( VEC_PERM_EXPR < {<<< Unknown tree:
compound_literal_expr
V D.1984 = { 0 }; >>>, { 0 }} , {<<< Unknown tree: compound_literal_expr
V D.1985 = { 0 }; >>>, { 0 }} , { 0, 0 } > & {(short int) SAVE_EXPR
<c>, (short int) SAVE_EXPR <c>});
where we gimplify the init CTORs to
_1 = {{ 0 }, { 0 }};
_2 = {{ 0 }, { 0 }};
instead of to vector constants. That later runs into a bug in
uniform_vector_p which doesn't handle CTORs of vector elements
correctly.
The following adjusts uniform_vector_p to handle CTORs of vector
elements and also makes sure to simplify the CTORs to VECTOR_CSTs
during gimplification by re-ordering the simplification to after
CTOR flag recomputation.
Bootstrapped and tested on x86_64-unknown-linux-gnu. At this
point I'm leaning towards delaying the gimplification change
to stage1 - do you agree?
Thanks,
Richard.
2022-03-25 Richard Biener <rguent...@suse.de>
PR middle-end/105049
* gimplify.cc (gimplify_init_constructor): First gimplify,
then simplify the result to a VECTOR_CST.
* tree.cc (uniform_vector_p): Recurse for VECTOR_CST or
CONSTRUCTOR first elements.
* gcc/testsuite/gcc.dg/pr105049.c: New testcase.
---
gcc/gimplify.cc | 33 ++++++++++++++++-----------------
gcc/testsuite/gcc.dg/pr105049.c | 12 ++++++++++++
gcc/tree.cc | 2 ++
3 files changed, 30 insertions(+), 17 deletions(-)
create mode 100644 gcc/testsuite/gcc.dg/pr105049.c
diff --git a/gcc/gimplify.cc b/gcc/gimplify.cc
index f62f150fc08..a866d4e6f56 100644
--- a/gcc/gimplify.cc
+++ b/gcc/gimplify.cc
@@ -5390,6 +5390,22 @@ gimplify_init_constructor (tree *expr_p, gimple_seq
*pre_p, gimple_seq *post_p,
if (notify_temp_creation)
return GS_OK;
+ /* Vector types use CONSTRUCTOR all the way through gimple
+ compilation as a general initializer. */
+ FOR_EACH_VEC_SAFE_ELT (elts, ix, ce)
+ {
+ enum gimplify_status tret;
+ tret = gimplify_expr (&ce->value, pre_p, post_p, is_gimple_val,
+ fb_rvalue);
+ if (tret == GS_ERROR)
+ ret = GS_ERROR;
+ else if (TREE_STATIC (ctor)
+ && !initializer_constant_valid_p (ce->value,
+ TREE_TYPE (ce->value)))
+ TREE_STATIC (ctor) = 0;
+ }
+ recompute_constructor_flags (ctor);
+
/* Go ahead and simplify constant constructors to VECTOR_CST. */
if (TREE_CONSTANT (ctor))
{
@@ -5412,25 +5428,8 @@ gimplify_init_constructor (tree *expr_p, gimple_seq
*pre_p, gimple_seq *post_p,
TREE_OPERAND (*expr_p, 1) = build_vector_from_ctor (type, elts);
break;
}
-
- TREE_CONSTANT (ctor) = 0;
}
- /* Vector types use CONSTRUCTOR all the way through gimple
- compilation as a general initializer. */
- FOR_EACH_VEC_SAFE_ELT (elts, ix, ce)
- {
- enum gimplify_status tret;
- tret = gimplify_expr (&ce->value, pre_p, post_p, is_gimple_val,
- fb_rvalue);
- if (tret == GS_ERROR)
- ret = GS_ERROR;
- else if (TREE_STATIC (ctor)
- && !initializer_constant_valid_p (ce->value,
- TREE_TYPE (ce->value)))
- TREE_STATIC (ctor) = 0;
- }
- recompute_constructor_flags (ctor);
if (!is_gimple_reg (TREE_OPERAND (*expr_p, 0)))
TREE_OPERAND (*expr_p, 1) = get_formal_tmp_var (ctor, pre_p);
}
diff --git a/gcc/testsuite/gcc.dg/pr105049.c b/gcc/testsuite/gcc.dg/pr105049.c
new file mode 100644
index 00000000000..b0518c6a181
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr105049.c
@@ -0,0 +1,12 @@
+/* { dg-do compile } */
+/* { dg-options "-O -fno-tree-forwprop" } */
+
+typedef short __attribute__((__vector_size__ (sizeof(short)))) V;
+typedef short __attribute__((__vector_size__ (2*sizeof(short)))) U;
+char c;
+
+U
+foo (void)
+{
+ return __builtin_shufflevector ((V){}, (V){}, 0, 0) & c;
+}
diff --git a/gcc/tree.cc b/gcc/tree.cc
index b8017af6cfc..ec200e9a7eb 100644
--- a/gcc/tree.cc
+++ b/gcc/tree.cc
@@ -10266,6 +10266,8 @@ uniform_vector_p (const_tree vec)
if (i != nelts)
return NULL_TREE;
+ if (TREE_CODE (first) == CONSTRUCTOR || TREE_CODE (first) == VECTOR_CST)
+ return uniform_vector_p (first);
return first;
}
--
2.34.1
