On May 11, 2020 6:41:58 PM GMT+02:00, Richard Sandiford
<richard.sandif...@arm.com> wrote:
>This third patch of three actually fixes the PR. We were using
>8-bit BIT_FIELD_REFs to access single-bit elements, and multiplying
>the vector index by 8 bits rather than 1 bit.
>
>Tested individually on aarch64-linux-gnu and as a series on
>x86_64-linux-gnu. OK to install?
OK.
>I'm not sure what to do about backports. Arguably the PR is
>really a progression rather than a regression, since we went
>from generating wrong code to ICEing. I'm not at all convinced
>that this fixes all the vector-lowering problems associated
>with packed booleans, and there's a danger that we could regress
>to wrong code if we backported a piecemeal fix.
I would suggest to wait for a real world case and only backport once we're
sufficiently sure the support is complete.
Richard
>Richard
>
>
>2020-05-11 Richard Sandiford <richard.sandif...@arm.com>
>
>gcc/
> PR tree-optimization/94980
> * tree-vect-generic.c (expand_vector_comparison): Use
> vector_element_bits_tree to get the element size in bits,
> rather than using TYPE_SIZE.
> (expand_vector_condition, vector_element): Likewise.
>
>gcc/testsuite/
> PR tree-optimization/94980
> * gcc.target/i386/pr94980.c: New test.
>---
> gcc/testsuite/gcc.target/i386/pr94980.c | 10 ++++++++++
> gcc/tree-vect-generic.c | 8 ++++----
> 2 files changed, 14 insertions(+), 4 deletions(-)
> create mode 100644 gcc/testsuite/gcc.target/i386/pr94980.c
>
>diff --git a/gcc/tree-vect-generic.c b/gcc/tree-vect-generic.c
>index adea9337a97..a7fe83da0e3 100644
>--- a/gcc/tree-vect-generic.c
>+++ b/gcc/tree-vect-generic.c
>@@ -390,7 +390,7 @@ expand_vector_comparison (gimple_stmt_iterator
>*gsi, tree type, tree op0,
> (TREE_TYPE (type)))))
> {
> tree inner_type = TREE_TYPE (TREE_TYPE (op0));
>- tree part_width = TYPE_SIZE (inner_type);
>+ tree part_width = vector_element_bits_tree (TREE_TYPE (op0));
> tree index = bitsize_int (0);
> int nunits = nunits_for_known_piecewise_op (TREE_TYPE (op0));
> int prec = GET_MODE_PRECISION (SCALAR_TYPE_MODE (type));
>@@ -944,9 +944,9 @@ expand_vector_condition (gimple_stmt_iterator *gsi)
> vec<constructor_elt, va_gc> *v;
> tree constr;
> tree inner_type = TREE_TYPE (type);
>+ tree width = vector_element_bits_tree (type);
> tree cond_type = TREE_TYPE (TREE_TYPE (a));
> tree comp_inner_type = cond_type;
>- tree width = TYPE_SIZE (inner_type);
> tree index = bitsize_int (0);
> tree comp_width = width;
> tree comp_index = index;
>@@ -960,7 +960,7 @@ expand_vector_condition (gimple_stmt_iterator *gsi)
> a1 = TREE_OPERAND (a, 0);
> a2 = TREE_OPERAND (a, 1);
> comp_inner_type = TREE_TYPE (TREE_TYPE (a1));
>- comp_width = TYPE_SIZE (comp_inner_type);
>+ comp_width = vector_element_bits_tree (TREE_TYPE (a1));
> }
>
> if (expand_vec_cond_expr_p (type, TREE_TYPE (a1), TREE_CODE (a)))
>@@ -1333,7 +1333,7 @@ vector_element (gimple_stmt_iterator *gsi, tree
>vect, tree idx, tree *ptmpvec)
> }
> else
> {
>- tree size = TYPE_SIZE (vect_elt_type);
>+ tree size = vector_element_bits_tree (vect_type);
> tree pos = fold_build2 (MULT_EXPR, bitsizetype, bitsize_int (index),
> size);
> return fold_build3 (BIT_FIELD_REF, vect_elt_type, vect, size, pos);
>diff --git a/gcc/testsuite/gcc.target/i386/pr94980.c
>b/gcc/testsuite/gcc.target/i386/pr94980.c
>new file mode 100644
>index 00000000000..488f94abec9
>--- /dev/null
>+++ b/gcc/testsuite/gcc.target/i386/pr94980.c
>@@ -0,0 +1,10 @@
>+/* { dg-do compile } */
>+/* { dg-options "-mavx512vl" } */
>+
>+int __attribute__((__vector_size__(16))) v;
>+
>+void
>+foo(void)
>+{
>+ 0 <= (0 != v) >= 0;
>+}
