On Mon, Nov 11, 2019 at 7:49 PM Richard Sandiford
<richard.sandif...@arm.com> wrote:
>
> This patch dumps the final (merged) list of alias pairs. It also adds:
>
> - WAW and RAW versions of vect-alias-check-8.c
> - a "well-ordered" version of vect-alias-check-9.c (i.e. all reads
> before any writes)
> - a test with mixed steps in the same alias pair
>
> I also tweaked the test value in vect-alias-check-9.c so that the result
> was less likely to be accidentally correct if the alias isn't honoured.
OK.
>
> 2019-11-11 Richard Sandiford <richard.sandif...@arm.com>
>
> gcc/
> * tree-data-ref.c (dump_alias_pair): New function.
> (prune_runtime_alias_test_list): Use it to dump each merged alias
> pair.
>
> gcc/testsuite/
> * gcc.dg/vect/vect-alias-check-8.c: Test for the RAW flag.
> * gcc.dg/vect/vect-alias-check-9.c: Test for the ARBITRARY flag.
> (TEST_VALUE): Use a higher value for early iterations.
> * gcc.dg/vect/vect-alias-check-14.c: New test.
> * gcc.dg/vect/vect-alias-check-15.c: Likewise.
> * gcc.dg/vect/vect-alias-check-16.c: Likewise.
> * gcc.dg/vect/vect-alias-check-17.c: Likewise.
>
> Index: gcc/tree-data-ref.c
> ===================================================================
> --- gcc/tree-data-ref.c 2019-11-11 18:30:53.863170161 +0000
> +++ gcc/tree-data-ref.c 2019-11-11 18:30:57.167147102 +0000
> @@ -1453,6 +1453,54 @@ comp_dr_with_seg_len_pair (const void *p
> return 0;
> }
>
> +/* Dump information about ALIAS_PAIR, indenting each line by INDENT. */
> +
> +static void
> +dump_alias_pair (dr_with_seg_len_pair_t *alias_pair, const char *indent)
> +{
> + dump_printf (MSG_NOTE, "%sreference: %T vs. %T\n", indent,
> + DR_REF (alias_pair->first.dr),
> + DR_REF (alias_pair->second.dr));
> +
> + dump_printf (MSG_NOTE, "%ssegment length: %T", indent,
> + alias_pair->first.seg_len);
> + if (!operand_equal_p (alias_pair->first.seg_len,
> + alias_pair->second.seg_len, 0))
> + dump_printf (MSG_NOTE, " vs. %T", alias_pair->second.seg_len);
> +
> + dump_printf (MSG_NOTE, "\n%saccess size: ", indent);
> + dump_dec (MSG_NOTE, alias_pair->first.access_size);
> + if (maybe_ne (alias_pair->first.access_size,
> alias_pair->second.access_size))
> + {
> + dump_printf (MSG_NOTE, " vs. ");
> + dump_dec (MSG_NOTE, alias_pair->second.access_size);
> + }
> +
> + dump_printf (MSG_NOTE, "\n%salignment: %d", indent,
> + alias_pair->first.align);
> + if (alias_pair->first.align != alias_pair->second.align)
> + dump_printf (MSG_NOTE, " vs. %d", alias_pair->second.align);
> +
> + dump_printf (MSG_NOTE, "\n%sflags: ", indent);
> + if (alias_pair->flags & DR_ALIAS_RAW)
> + dump_printf (MSG_NOTE, " RAW");
> + if (alias_pair->flags & DR_ALIAS_WAR)
> + dump_printf (MSG_NOTE, " WAR");
> + if (alias_pair->flags & DR_ALIAS_WAW)
> + dump_printf (MSG_NOTE, " WAW");
> + if (alias_pair->flags & DR_ALIAS_ARBITRARY)
> + dump_printf (MSG_NOTE, " ARBITRARY");
> + if (alias_pair->flags & DR_ALIAS_SWAPPED)
> + dump_printf (MSG_NOTE, " SWAPPED");
> + if (alias_pair->flags & DR_ALIAS_UNSWAPPED)
> + dump_printf (MSG_NOTE, " UNSWAPPED");
> + if (alias_pair->flags & DR_ALIAS_MIXED_STEPS)
> + dump_printf (MSG_NOTE, " MIXED_STEPS");
> + if (alias_pair->flags == 0)
> + dump_printf (MSG_NOTE, " <none>");
> + dump_printf (MSG_NOTE, "\n");
> +}
> +
> /* Merge alias checks recorded in ALIAS_PAIRS and remove redundant ones.
> FACTOR is number of iterations that each data reference is accessed.
>
> @@ -1656,6 +1704,8 @@ prune_runtime_alias_test_list (vec<dr_wi
> dr_with_seg_len_pair_t. If we ended up combining swapped and
> unswapped pairs into the same check, we have to invalidate any
> RAW, WAR and WAW information for it. */
> + if (dump_enabled_p ())
> + dump_printf (MSG_NOTE, "merged alias checks:\n");
> FOR_EACH_VEC_ELT (*alias_pairs, i, alias_pair)
> {
> unsigned int swap_mask = (DR_ALIAS_SWAPPED | DR_ALIAS_UNSWAPPED);
> @@ -1665,6 +1715,8 @@ prune_runtime_alias_test_list (vec<dr_wi
> else if (swapped != DR_ALIAS_UNSWAPPED)
> alias_pair->flags |= DR_ALIAS_ARBITRARY;
> alias_pair->flags &= ~swap_mask;
> + if (dump_enabled_p ())
> + dump_alias_pair (alias_pair, " ");
> }
> }
>
> Index: gcc/testsuite/gcc.dg/vect/vect-alias-check-8.c
> ===================================================================
> --- gcc/testsuite/gcc.dg/vect/vect-alias-check-8.c 2019-03-08
> 18:15:02.280871184 +0000
> +++ gcc/testsuite/gcc.dg/vect/vect-alias-check-8.c 2019-11-11
> 18:30:57.167147102 +0000
> @@ -58,3 +58,5 @@ main (void)
> FOR_EACH_TYPE (DO_TEST)
> return 0;
> }
> +
> +/* { dg-final { scan-tree-dump {flags: *WAR\n} "vect" { target vect_int } }
> } */
> Index: gcc/testsuite/gcc.dg/vect/vect-alias-check-9.c
> ===================================================================
> --- gcc/testsuite/gcc.dg/vect/vect-alias-check-9.c 2019-03-08
> 18:15:02.244871320 +0000
> +++ gcc/testsuite/gcc.dg/vect/vect-alias-check-9.c 2019-11-11
> 18:30:57.167147102 +0000
> @@ -17,7 +17,7 @@ #define FOR_EACH_TYPE(M) \
> M (sll) M (ull) \
> M (float) M (double)
>
> -#define TEST_VALUE(I) ((I) * 5 / 2)
> +#define TEST_VALUE(I) ((I) * 17 / 2)
>
> #define ADD_TEST(TYPE) \
> void __attribute__((noinline, noclone)) \
> @@ -51,3 +51,5 @@ main (void)
> FOR_EACH_TYPE (DO_TEST)
> return 0;
> }
> +
> +/* { dg-final { scan-tree-dump {flags: [^\n]*ARBITRARY\n} "vect" { target
> vect_int } } } */
> Index: gcc/testsuite/gcc.dg/vect/vect-alias-check-14.c
> ===================================================================
> --- /dev/null 2019-09-17 11:41:18.176664108 +0100
> +++ gcc/testsuite/gcc.dg/vect/vect-alias-check-14.c 2019-11-11
> 18:30:57.167147102 +0000
> @@ -0,0 +1,62 @@
> +#define N 200
> +#define M 4
> +
> +typedef signed char sc;
> +typedef unsigned char uc;
> +typedef signed short ss;
> +typedef unsigned short us;
> +typedef int si;
> +typedef unsigned int ui;
> +typedef signed long long sll;
> +typedef unsigned long long ull;
> +
> +#define FOR_EACH_TYPE(M) \
> + M (sc) M (uc) \
> + M (ss) M (us) \
> + M (si) M (ui) \
> + M (sll) M (ull) \
> + M (float) M (double)
> +
> +#define TEST_VALUE(I) ((I) * 17 / 2)
> +
> +#define ADD_TEST(TYPE) \
> + void __attribute__((noinline, noclone)) \
> + test_##TYPE (TYPE *a, TYPE *b) \
> + { \
> + for (int i = 0; i < N; i += 2) \
> + { \
> + TYPE b0 = b[i + 0]; \
> + TYPE b1 = b[i + 1]; \
> + a[i + 0] = b0 + 2; \
> + a[i + 1] = b1 + 3; \
> + } \
> + }
> +
> +#define DO_TEST(TYPE) \
> + for (int j = 0; j < M; ++j) \
> + { \
> + TYPE a[N + M]; \
> + for (int i = 0; i < N + M; ++i) \
> + a[i] = TEST_VALUE (i); \
> + test_##TYPE (a + j, a); \
> + for (int i = 0; i < N; i += 2) \
> + { \
> + TYPE base1 = j == 0 ? TEST_VALUE (i) : a[i]; \
> + TYPE base2 = j <= 1 ? TEST_VALUE (i + 1) : a[i + 1]; \
> + if (a[i + j] != (TYPE) (base1 + 2) \
> + || a[i + j + 1] != (TYPE) (base2 + 3)) \
> + __builtin_abort (); \
> + } \
> + }
> +
> +FOR_EACH_TYPE (ADD_TEST)
> +
> +int
> +main (void)
> +{
> + FOR_EACH_TYPE (DO_TEST)
> + return 0;
> +}
> +
> +/* { dg-final { scan-tree-dump {flags: *WAR\n} "vect" { target vect_int } }
> } */
> +/* { dg-final { scan-tree-dump-not {flags: [^\n]*ARBITRARY\n} "vect" } } */
> Index: gcc/testsuite/gcc.dg/vect/vect-alias-check-15.c
> ===================================================================
> --- /dev/null 2019-09-17 11:41:18.176664108 +0100
> +++ gcc/testsuite/gcc.dg/vect/vect-alias-check-15.c 2019-11-11
> 18:30:57.167147102 +0000
> @@ -0,0 +1,59 @@
> +#define N 200
> +#define DIST 32
> +
> +typedef signed char sc;
> +typedef unsigned char uc;
> +typedef signed short ss;
> +typedef unsigned short us;
> +typedef int si;
> +typedef unsigned int ui;
> +typedef signed long long sll;
> +typedef unsigned long long ull;
> +
> +#define FOR_EACH_TYPE(M) \
> + M (sc) M (uc) \
> + M (ss) M (us) \
> + M (si) M (ui) \
> + M (sll) M (ull) \
> + M (float) M (double)
> +
> +#define ADD_TEST(TYPE) \
> + void __attribute__((noinline, noclone)) \
> + test_##TYPE (TYPE *x, TYPE *y) \
> + { \
> + for (int i = 0; i < N; ++i) \
> + { \
> + x[i] = i; \
> + y[i] = 42 - i * 2; \
> + } \
> + }
> +
> +#define DO_TEST(TYPE) \
> + for (int i = 0; i < DIST * 2; ++i) \
> + { \
> + TYPE a[N + DIST * 2] = {}; \
> + test_##TYPE (a + DIST, a + i); \
> + for (int j = 0; j < N + DIST * 2; ++j) \
> + { \
> + TYPE expected = 0; \
> + if (i > DIST && j >= i && j < i + N) \
> + expected = 42 - (j - i) * 2; \
> + if (j >= DIST && j < DIST + N) \
> + expected = j - DIST; \
> + if (i <= DIST && j >= i && j < i + N) \
> + expected = 42 - (j - i) * 2; \
> + if (expected != a[j]) \
> + __builtin_abort (); \
> + } \
> + }
> +
> +FOR_EACH_TYPE (ADD_TEST)
> +
> +int
> +main (void)
> +{
> + FOR_EACH_TYPE (DO_TEST)
> + return 0;
> +}
> +
> +/* { dg-final { scan-tree-dump {flags: *WAW\n} "vect" { target vect_int } }
> } */
> Index: gcc/testsuite/gcc.dg/vect/vect-alias-check-16.c
> ===================================================================
> --- /dev/null 2019-09-17 11:41:18.176664108 +0100
> +++ gcc/testsuite/gcc.dg/vect/vect-alias-check-16.c 2019-11-11
> 18:30:57.167147102 +0000
> @@ -0,0 +1,64 @@
> +#define N 200
> +#define DIST 32
> +
> +typedef signed char sc;
> +typedef unsigned char uc;
> +typedef signed short ss;
> +typedef unsigned short us;
> +typedef int si;
> +typedef unsigned int ui;
> +typedef signed long long sll;
> +typedef unsigned long long ull;
> +
> +#define FOR_EACH_TYPE(M) \
> + M (sc) M (uc) \
> + M (ss) M (us) \
> + M (si) M (ui) \
> + M (sll) M (ull) \
> + M (float) M (double)
> +
> +#define TEST_VALUE(I) ((I) * 13 / 2)
> +
> +#define ADD_TEST(TYPE) \
> + TYPE __attribute__((noinline, noclone)) \
> + test_##TYPE (TYPE *x, TYPE *y) \
> + { \
> + TYPE res = 0; \
> + for (int i = 0; i < N; ++i) \
> + { \
> + x[i] = i; \
> + res += y[i]; \
> + } \
> + return res; \
> + }
> +
> +#define DO_TEST(TYPE) \
> + for (int i = 0; i < DIST * 2; ++i) \
> + { \
> + TYPE a[N + DIST * 2]; \
> + for (int j = 0; j < N + DIST * 2; ++j) \
> + a[j] = TEST_VALUE (j); \
> + TYPE res = test_##TYPE (a + DIST, a + i); \
> + for (int j = 0; j < N; ++j) \
> + if (a[j + DIST] != (TYPE) j) \
> + __builtin_abort (); \
> + TYPE expected_res = 0; \
> + for (int j = i; j < i + N; ++j) \
> + if (i <= DIST && j >= DIST && j < DIST + N) \
> + expected_res += j - DIST; \
> + else \
> + expected_res += TEST_VALUE (j); \
> + if (expected_res != res) \
> + __builtin_abort (); \
> + }
> +
> +FOR_EACH_TYPE (ADD_TEST)
> +
> +int
> +main (void)
> +{
> + FOR_EACH_TYPE (DO_TEST)
> + return 0;
> +}
> +
> +/* { dg-final { scan-tree-dump {flags: *RAW\n} "vect" { target vect_int } }
> } */
> Index: gcc/testsuite/gcc.dg/vect/vect-alias-check-17.c
> ===================================================================
> --- /dev/null 2019-09-17 11:41:18.176664108 +0100
> +++ gcc/testsuite/gcc.dg/vect/vect-alias-check-17.c 2019-11-11
> 18:30:57.167147102 +0000
> @@ -0,0 +1,13 @@
> +/* { dg-do compile } */
> +/* { dg-require-effective-target vect_load_lanes } */
> +
> +struct s { int x[100]; };
> +
> +void
> +f (struct s *s1, int a, int b)
> +{
> + for (int i = 0; i < 32; ++i)
> + s1->x[a + i] = s1->x[b + i * 2] + s1->x[b + i * 3];
> +}
> +
> +/* { dg-final { scan-tree-dump {flags: *[^\n]*MIXED_STEPS} "vect" } } */
