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Fixed incorrect TARGET_MEM_REF alignment (PR 84419)
- From: Richard Sandiford <richard dot sandiford at linaro dot org>
- To: gcc-patches at gcc dot gnu dot org
- Date: Tue, 20 Feb 2018 09:43:40 +0000
- Subject: Fixed incorrect TARGET_MEM_REF alignment (PR 84419)
- Authentication-results: sourceware.org; auth=none
expand_call_mem_ref checks for TARGET_MEM_REFs that have compatible
type, but it didn't then go on to install the specific type we need,
which might have different alignment due to:
if (TYPE_ALIGN (type) != align)
type = build_aligned_type (type, align);
This was causing masked stores to be incorrectly marked as
aligned on AVX512.
Tested on aarch64-linux-gnu, x86_64-linux-gnu and powerpc64-linux-gnu.
Also tested by Alexander on AVX512 hw. OK to install?
Richard
2018-02-20 Richard Sandiford <richard.sandiford@linaro.org>
gcc/
PR tree-optimization/84419
* internal-fn.c (expand_call_mem_ref): Create a TARGET_MEM_REF
with the required type if its current type is compatible but
different.
gcc/testsuite/
PR tree-optimization/84419
* gcc.dg/vect/pr84419.c: New test.
Index: gcc/internal-fn.c
===================================================================
--- gcc/internal-fn.c 2018-01-13 18:01:51.235735290 +0000
+++ gcc/internal-fn.c 2018-02-20 09:40:47.547217244 +0000
@@ -2444,11 +2444,14 @@ expand_call_mem_ref (tree type, gcall *s
&& types_compatible_p (TREE_TYPE (mem), type))
{
tree offset = TMR_OFFSET (mem);
- if (alias_ptr_type != TREE_TYPE (offset) || !integer_zerop (offset))
+ if (type != TREE_TYPE (mem)
+ || alias_ptr_type != TREE_TYPE (offset)
+ || !integer_zerop (offset))
{
mem = copy_node (mem);
TMR_OFFSET (mem) = wide_int_to_tree (alias_ptr_type,
wi::to_poly_wide (offset));
+ TREE_TYPE (mem) = type;
}
return mem;
}
Index: gcc/testsuite/gcc.dg/vect/pr84419.c
===================================================================
--- /dev/null 2018-02-19 19:34:42.906488063 +0000
+++ gcc/testsuite/gcc.dg/vect/pr84419.c 2018-02-20 09:40:47.548217201 +0000
@@ -0,0 +1,21 @@
+#include <string.h>
+
+#define SIZE 400
+
+int foo[SIZE];
+char bar[SIZE];
+
+void __attribute__ ((noinline)) foo_func(void)
+{
+ int i;
+ for (i = 1; i < SIZE; i++)
+ if (bar[i])
+ foo[i] = 1;
+}
+
+int main()
+{
+ memset(bar, 1, sizeof(bar));
+ foo_func();
+ return 0;
+}