On Thu, 25 Sep 2014, Jakub Jelinek wrote:
> Hi!
>
> As the testcases show, dr_explicit_realign_optimized (used on PowerPC/SPU
> only) misbehaves if the base_address is in between 1 and vector element size
> - 1
> modulo vector size.
> The problem is that it wants to add a bias to base_addr such that
> base_addr & ~vector_size
> (base_addr + bias) & ~vector_size
> are adjacent vector_size memory slots, but vect_create_data_ref_ptr
> takes offset counted in vector elements and in the end multiplies that
> by vector element size, so we end up actually with:
> (base_addr + ((vector_size / vector_element_size) * vector_element_size) &
> ~vector_size
> which unfortunately is not enough, e.g. in the testcase
> base_addr is 1 moduo vector_size, vector_size 16 and vector_element_size 2,
> so we have
> base_addr & ~16
> (base_addr + 14) & ~16
> instead of the desired
> (base_addr + 15) & ~16
> and 1 & ~16 and (1 + 14) & ~16 is the same address.
>
> Fixed by passing another offset, measured in bytes (for the negative case
> which are the only 3 other cases which pass any offset down we want it to be
> as is), bootstrapped/regtested on x86_64-linux and i686-linux and on
> {x86_64,i686,powerpc{,64},s390{,x}}-linux on the 4.8 branch.
>
> Ok for trunk/4.9/4.8?
Ok.
Thanks,
Richard.
> 2014-09-25 Jakub Jelinek <[email protected]>
>
> PR tree-optimization/63341
> * tree-vectorizer.h (vect_create_data_ref_ptr,
> vect_create_addr_base_for_vector_ref): Add another tree argument
> defaulting to NULL_TREE.
> * tree-vect-data-refs.c (vect_create_data_ref_ptr): Add byte_offset
> argument, pass it down to vect_create_addr_base_for_vector_ref.
> (vect_create_addr_base_for_vector_ref): Add byte_offset argument,
> add that to base_offset too if non-NULL.
> * tree-vect-stmts.c (vectorizable_load): Add byte_offset variable,
> for dr_explicit_realign_optimized set it to vector byte size
> - 1 instead of setting offset, pass byte_offset down to
> vect_create_data_ref_ptr.
>
> * gcc.dg/vect/pr63341-1.c: New test.
> * gcc.dg/vect/pr63341-2.c: New test.
>
> --- gcc/tree-vectorizer.h.jj 2014-09-01 09:43:56.000000000 +0200
> +++ gcc/tree-vectorizer.h 2014-09-23 15:19:28.302484227 +0200
> @@ -1061,7 +1061,8 @@ extern bool vect_analyze_data_refs (loop
> unsigned *);
> extern tree vect_create_data_ref_ptr (gimple, tree, struct loop *, tree,
> tree *, gimple_stmt_iterator *,
> - gimple *, bool, bool *);
> + gimple *, bool, bool *,
> + tree = NULL_TREE);
> extern tree bump_vector_ptr (tree, gimple, gimple_stmt_iterator *, gimple,
> tree);
> extern tree vect_create_destination_var (tree, tree);
> extern bool vect_grouped_store_supported (tree, unsigned HOST_WIDE_INT);
> @@ -1078,7 +1079,8 @@ extern void vect_transform_grouped_load
> extern void vect_record_grouped_load_vectors (gimple, vec<tree> );
> extern tree vect_get_new_vect_var (tree, enum vect_var_kind, const char *);
> extern tree vect_create_addr_base_for_vector_ref (gimple, gimple_seq *,
> - tree, struct loop *);
> + tree, struct loop *,
> + tree = NULL_TREE);
>
> /* In tree-vect-loop.c. */
> /* FORNOW: Used in tree-parloops.c. */
> --- gcc/tree-vect-data-refs.c.jj 2014-09-18 15:48:22.000000000 +0200
> +++ gcc/tree-vect-data-refs.c 2014-09-23 15:11:06.163061112 +0200
> @@ -3860,6 +3860,9 @@ vect_get_new_vect_var (tree type, enum v
> is as follows:
> if LOOP=i_loop: &in (relative to i_loop)
> if LOOP=j_loop: &in+i*2B (relative to j_loop)
> + BYTE_OFFSET: Optional, defaulted to NULL. If supplied, it is added to the
> + initial address. Unlike OFFSET, which is number of elements to
> + be added, BYTE_OFFSET is measured in bytes.
>
> Output:
> 1. Return an SSA_NAME whose value is the address of the memory location of
> @@ -3873,7 +3876,8 @@ tree
> vect_create_addr_base_for_vector_ref (gimple stmt,
> gimple_seq *new_stmt_list,
> tree offset,
> - struct loop *loop)
> + struct loop *loop,
> + tree byte_offset)
> {
> stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
> struct data_reference *dr = STMT_VINFO_DATA_REF (stmt_info);
> @@ -3926,6 +3930,12 @@ vect_create_addr_base_for_vector_ref (gi
> base_offset = fold_build2 (PLUS_EXPR, sizetype,
> base_offset, offset);
> }
> + if (byte_offset)
> + {
> + byte_offset = fold_convert (sizetype, byte_offset);
> + base_offset = fold_build2 (PLUS_EXPR, sizetype,
> + base_offset, byte_offset);
> + }
>
> /* base + base_offset */
> if (loop_vinfo)
> @@ -3983,6 +3993,10 @@ vect_create_addr_base_for_vector_ref (gi
> 5. BSI: location where the new stmts are to be placed if there is no loop
> 6. ONLY_INIT: indicate if ap is to be updated in the loop, or remain
> pointing to the initial address.
> + 7. BYTE_OFFSET (optional, defaults to NULL): a byte offset to be added
> + to the initial address accessed by the data-ref in STMT. This is
> + similar to OFFSET, but OFFSET is counted in elements, while BYTE_OFFSET
> + in bytes.
>
> Output:
> 1. Declare a new ptr to vector_type, and have it point to the base of the
> @@ -3996,6 +4010,8 @@ vect_create_addr_base_for_vector_ref (gi
> initial_address = &a[init];
> if OFFSET is supplied:
> initial_address = &a[init + OFFSET];
> + if BYTE_OFFSET is supplied:
> + initial_address = &a[init] + BYTE_OFFSET;
>
> Return the initial_address in INITIAL_ADDRESS.
>
> @@ -4013,7 +4029,7 @@ tree
> vect_create_data_ref_ptr (gimple stmt, tree aggr_type, struct loop *at_loop,
> tree offset, tree *initial_address,
> gimple_stmt_iterator *gsi, gimple *ptr_incr,
> - bool only_init, bool *inv_p)
> + bool only_init, bool *inv_p, tree byte_offset)
> {
> const char *base_name;
> stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
> @@ -4156,10 +4172,10 @@ vect_create_data_ref_ptr (gimple stmt, t
> /* (2) Calculate the initial address of the aggregate-pointer, and set
> the aggregate-pointer to point to it before the loop. */
>
> - /* Create: (&(base[init_val+offset]) in the loop preheader. */
> + /* Create: (&(base[init_val+offset]+byte_offset) in the loop preheader. */
>
> new_temp = vect_create_addr_base_for_vector_ref (stmt, &new_stmt_list,
> - offset, loop);
> + offset, loop, byte_offset);
> if (new_stmt_list)
> {
> if (pe)
> --- gcc/tree-vect-stmts.c.jj 2014-08-01 09:24:12.000000000 +0200
> +++ gcc/tree-vect-stmts.c 2014-09-23 15:09:31.832553172 +0200
> @@ -5600,6 +5600,7 @@ vectorizable_load (gimple stmt, gimple_s
> int i, j, group_size, group_gap;
> tree msq = NULL_TREE, lsq;
> tree offset = NULL_TREE;
> + tree byte_offset = NULL_TREE;
> tree realignment_token = NULL_TREE;
> gimple phi = NULL;
> vec<tree> dr_chain = vNULL;
> @@ -6261,7 +6262,8 @@ vectorizable_load (gimple stmt, gimple_s
> if (alignment_support_scheme == dr_explicit_realign_optimized)
> {
> phi = SSA_NAME_DEF_STMT (msq);
> - offset = size_int (TYPE_VECTOR_SUBPARTS (vectype) - 1);
> + byte_offset = size_binop (MINUS_EXPR, TYPE_SIZE_UNIT (vectype),
> + size_one_node);
> }
> }
> else
> @@ -6302,7 +6304,8 @@ vectorizable_load (gimple stmt, gimple_s
> dataref_ptr
> = vect_create_data_ref_ptr (first_stmt, aggr_type, at_loop,
> offset, &dummy, gsi, &ptr_incr,
> - simd_lane_access_p, &inv_p);
> + simd_lane_access_p, &inv_p,
> + byte_offset);
> }
> else if (dataref_offset)
> dataref_offset = int_const_binop (PLUS_EXPR, dataref_offset,
> --- gcc/testsuite/gcc.dg/vect/pr63341-1.c.jj 2014-09-23 15:27:24.658025472
> +0200
> +++ gcc/testsuite/gcc.dg/vect/pr63341-1.c 2014-09-23 15:28:16.645757979
> +0200
> @@ -0,0 +1,32 @@
> +/* PR tree-optimization/63341 */
> +/* { dg-do run } */
> +
> +#include "tree-vect.h"
> +
> +typedef union U { unsigned short s; unsigned char c; }
> __attribute__((packed)) U;
> +struct S { char e __attribute__((aligned (64))); U s[32]; };
> +struct S t = {0, {{1}, {2}, {3}, {4}, {5}, {6}, {7}, {8},
> + {9}, {10}, {11}, {12}, {13}, {14}, {15}, {16},
> + {17}, {18}, {19}, {20}, {21}, {22}, {23}, {24},
> + {25}, {26}, {27}, {28}, {29}, {30}, {31}, {32}}};
> +unsigned short d[32] = { 1 };
> +
> +__attribute__((noinline, noclone)) void
> +foo ()
> +{
> + int i;
> + for (i = 0; i < 32; i++)
> + d[i] = t.s[i].s;
> + if (__builtin_memcmp (d, t.s, sizeof d))
> + abort ();
> +}
> +
> +int
> +main ()
> +{
> + check_vect ();
> + foo ();
> + return 0;
> +}
> +
> +/* { dg-final { cleanup-tree-dump "vect" } } */
> --- gcc/testsuite/gcc.dg/vect/pr63341-2.c.jj 2014-09-23 15:27:27.906013904
> +0200
> +++ gcc/testsuite/gcc.dg/vect/pr63341-2.c 2014-09-23 15:30:29.874081634
> +0200
> @@ -0,0 +1,35 @@
> +/* PR tree-optimization/63341 */
> +/* { dg-do run } */
> +
> +#include "tree-vect.h"
> +
> +typedef union U { unsigned short s; unsigned char c; }
> __attribute__((packed)) U;
> +struct S { char e __attribute__((aligned (64))); U s[32]; };
> +struct S t = {0, {{0x5010}, {0x5111}, {0x5212}, {0x5313}, {0x5414},
> {0x5515}, {0x5616}, {0x5717},
> + {0x5818}, {0x5919}, {0x5a1a}, {0x5b1b}, {0x5c1c}, {0x5d1d},
> {0x5e1e}, {0x5f1f},
> + {0x6020}, {0x6121}, {0x6222}, {0x6323}, {0x6424}, {0x6525},
> {0x6626}, {0x6727},
> + {0x6828}, {0x6929}, {0x6a2a}, {0x6b2b}, {0x6c2c}, {0x6d2d},
> {0x6e2e}, {0x6f2f}}};
> +unsigned short d[32] = { 1 };
> +
> +__attribute__((noinline, noclone)) void
> +foo ()
> +{
> + int i;
> + for (i = 0; i < 32; i++)
> + d[i] = t.s[i].s + 4;
> + for (i = 0; i < 32; i++)
> + if (d[i] != t.s[i].s + 4)
> + abort ();
> + else
> + asm volatile ("" : : : "memory");
> +}
> +
> +int
> +main ()
> +{
> + check_vect ();
> + foo ();
> + return 0;
> +}
> +
> +/* { dg-final { cleanup-tree-dump "vect" } } */
>
> Jakub
>
>
--
Richard Biener <[email protected]>
SUSE / SUSE Labs
SUSE LINUX Products GmbH - Nuernberg - AG Nuernberg - HRB 16746
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