On Thu, Oct 12, 2017 at 2:32 PM, Richard Biener
<richard.guent...@gmail.com> wrote:
> On Thu, Oct 5, 2017 at 3:17 PM, Bin Cheng <bin.ch...@arm.com> wrote:
>> Hi,
>> This patch rewrites classification part of builtin partition so that nested
>> builtin partitions are supported. With this extension, below loop nest:
>> void
>> foo (void)
>> {
>> for (unsigned i = 0; i < M; ++i)
>> for (unsigned j = 0; j < N; ++j)
>> arr[i][j] = 0;
>>
>> will be distributed into a single memset, rather than a loop of memset.
>> Bootstrap and test in patch set on x86_64 and AArch64, is it OK?
>
> + tree access_size = fold_convert (sizetype, TYPE_SIZE_UNIT (TREE_TYPE
> (ref)));
> +
>
> TYPE_SIZE_UNIT should be always sizetype.
Done.
>
> + /* Classify the builtin kind. */
> + if (single_ld == NULL)
> + classify_builtin_1 (loop, partition, single_st);
> + else
> + classify_builtin_2 (loop, rdg, partition, single_st, single_ld);
>
> maybe name those helpers classify_builtin_st and classify_builtin_ldst?
Done. Patch updated in attachment, Will apply it later.
Thanks,
bin
2017-10-12 Bin Cheng <bin.ch...@arm.com>
* tree-loop-distribution.c (struct builtin_info): New struct.
(struct partition): Refactor fields into struct builtin_info.
(partition_free): Free struct builtin_info.
(build_size_arg_loc, build_addr_arg_loc): Delete.
(generate_memset_builtin, generate_memcpy_builtin): Get memory range
information from struct builtin_info.
(find_single_drs): New function refactored from classify_partition.
Also moved builtin validity checks to this function.
(compute_access_range, alloc_builtin): New functions.
(classify_builtin_st, classify_builtin_ldst): New functions.
(classify_partition): Refactor code into functions find_single_drs,
classify_builtin_st and classify_builtin_ldst.
(distribute_loop): Don't do runtime alias check when distributing
loop nest.
(find_seed_stmts_for_distribution): New function.
(pass_loop_distribution::execute): Refactor code finding seed
stmts into above function. Support distribution for the innermost
two-level loop nest. Adjust dump information.
gcc/testsuite/ChangeLog
2017-10-12 Bin Cheng <bin.ch...@arm.com>
* gcc.dg/tree-ssa/ldist-28.c: New test.
* gcc.dg/tree-ssa/ldist-29.c: New test.
* gcc.dg/tree-ssa/ldist-30.c: New test.
* gcc.dg/tree-ssa/ldist-31.c: New test.
>
> Ok with those changes.
>
> Thanks,
> Richard.
>
From 8271ce0851a60b38226e92558bca234774e5503e Mon Sep 17 00:00:00 2001
From: Bin Cheng <binch...@e108451-lin.cambridge.arm.com>
Date: Wed, 27 Sep 2017 13:00:59 +0100
Subject: [PATCH 6/7] loop_nest-builtin-pattern-20171012.txt
---
gcc/testsuite/gcc.dg/tree-ssa/ldist-28.c | 16 +
gcc/testsuite/gcc.dg/tree-ssa/ldist-29.c | 17 ++
gcc/testsuite/gcc.dg/tree-ssa/ldist-30.c | 16 +
gcc/testsuite/gcc.dg/tree-ssa/ldist-31.c | 19 ++
gcc/tree-loop-distribution.c | 507 +++++++++++++++++++------------
5 files changed, 377 insertions(+), 198 deletions(-)
create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/ldist-28.c
create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/ldist-29.c
create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/ldist-30.c
create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/ldist-31.c
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/ldist-28.c b/gcc/testsuite/gcc.dg/tree-ssa/ldist-28.c
new file mode 100644
index 0000000..4420139
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/ldist-28.c
@@ -0,0 +1,16 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -ftree-loop-distribution -ftree-loop-distribute-patterns -fdump-tree-ldist-details" } */
+
+#define M (256)
+#define N (1024)
+int arr[M][N];
+
+void
+foo (void)
+{
+ for (unsigned i = 0; i < M; ++i)
+ for (unsigned j = 0; j < N; ++j)
+ arr[i][j] = 0;
+}
+
+/* { dg-final { scan-tree-dump "Loop nest . distributed: split to 0 loops and 1 library" "ldist" } } */
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/ldist-29.c b/gcc/testsuite/gcc.dg/tree-ssa/ldist-29.c
new file mode 100644
index 0000000..9ce93e8
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/ldist-29.c
@@ -0,0 +1,17 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -ftree-loop-distribution -ftree-loop-distribute-patterns -fdump-tree-ldist-details" } */
+
+#define M (256)
+#define N (512)
+int arr[M][N];
+
+void
+foo (void)
+{
+ for (unsigned i = 0; i < M; ++i)
+ for (unsigned j = 0; j < N - 1; ++j)
+ arr[i][j] = 0;
+}
+
+/* { dg-final { scan-tree-dump-not "Loop nest . distributed: split to" "ldist" } } */
+/* { dg-final { scan-tree-dump-times "Loop . distributed: split to 0 loops and 1 library" 1 "ldist" } } */
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/ldist-30.c b/gcc/testsuite/gcc.dg/tree-ssa/ldist-30.c
new file mode 100644
index 0000000..f31860a
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/ldist-30.c
@@ -0,0 +1,16 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -ftree-loop-distribution -ftree-loop-distribute-patterns -fdump-tree-ldist-details" } */
+
+#define M (256)
+#define N (512)
+int a[M][N], b[M][N];
+
+void
+foo (void)
+{
+ for (unsigned i = 0; i < M; ++i)
+ for (unsigned j = N; j > 0; --j)
+ a[i][j - 1] = b[i][j - 1];
+}
+
+/* { dg-final { scan-tree-dump-times "Loop nest . distributed: split to" 1 "ldist" } } */
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/ldist-31.c b/gcc/testsuite/gcc.dg/tree-ssa/ldist-31.c
new file mode 100644
index 0000000..60a9f74
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/ldist-31.c
@@ -0,0 +1,19 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -ftree-loop-distribution -ftree-loop-distribute-patterns -fdump-tree-ldist-details" } */
+
+#define M (256)
+#define N (512)
+int a[M][N], b[M][N], c[M];
+
+void
+foo (void)
+{
+ for (int i = M - 1; i >= 0; --i)
+ {
+ c[i] = 0;
+ for (unsigned j = N; j > 0; --j)
+ a[i][j - 1] = b[i][j - 1];
+ }
+}
+
+/* { dg-final { scan-tree-dump-times "Loop nest . distributed: split to 0 loops and 2 library" 1 "ldist" } } */
diff --git a/gcc/tree-loop-distribution.c b/gcc/tree-loop-distribution.c
index 7040669..a83c073 100644
--- a/gcc/tree-loop-distribution.c
+++ b/gcc/tree-loop-distribution.c
@@ -593,6 +593,19 @@ enum partition_type {
PTYPE_SEQUENTIAL
};
+/* Builtin info for loop distribution. */
+struct builtin_info
+{
+ /* data-references a kind != PKIND_NORMAL partition is about. */
+ data_reference_p dst_dr;
+ data_reference_p src_dr;
+ /* Base address and size of memory objects operated by the builtin. Note
+ both dest and source memory objects must have the same size. */
+ tree dst_base;
+ tree src_base;
+ tree size;
+};
+
/* Partition for loop distribution. */
struct partition
{
@@ -600,18 +613,12 @@ struct partition
bitmap stmts;
/* True if the partition defines variable which is used outside of loop. */
bool reduction_p;
- /* For builtin partition, true if it executes one iteration more than
- number of loop (latch) iterations. */
- bool plus_one;
enum partition_kind kind;
enum partition_type type;
- /* data-references a kind != PKIND_NORMAL partition is about. */
- data_reference_p main_dr;
- data_reference_p secondary_dr;
- /* Number of loop (latch) iterations. */
- tree niter;
/* Data references in the partition. */
bitmap datarefs;
+ /* Information of builtin parition. */
+ struct builtin_info *builtin;
};
@@ -635,6 +642,9 @@ partition_free (partition *partition)
{
BITMAP_FREE (partition->stmts);
BITMAP_FREE (partition->datarefs);
+ if (partition->builtin)
+ free (partition->builtin);
+
free (partition);
}
@@ -894,43 +904,6 @@ generate_loops_for_partition (struct loop *loop, partition *partition,
free (bbs);
}
-/* Build the size argument for a memory operation call. */
-
-static tree
-build_size_arg_loc (location_t loc, data_reference_p dr, tree nb_iter,
- bool plus_one)
-{
- tree size = fold_convert_loc (loc, sizetype, nb_iter);
- if (plus_one)
- size = size_binop (PLUS_EXPR, size, size_one_node);
- size = fold_build2_loc (loc, MULT_EXPR, sizetype, size,
- TYPE_SIZE_UNIT (TREE_TYPE (DR_REF (dr))));
- size = fold_convert_loc (loc, size_type_node, size);
- return size;
-}
-
-/* Build an address argument for a memory operation call. */
-
-static tree
-build_addr_arg_loc (location_t loc, data_reference_p dr, tree nb_bytes)
-{
- tree addr_base;
-
- addr_base = size_binop_loc (loc, PLUS_EXPR, DR_OFFSET (dr), DR_INIT (dr));
- addr_base = fold_convert_loc (loc, sizetype, addr_base);
-
- /* Test for a negative stride, iterating over every element. */
- if (tree_int_cst_sgn (DR_STEP (dr)) == -1)
- {
- addr_base = size_binop_loc (loc, MINUS_EXPR, addr_base,
- fold_convert_loc (loc, sizetype, nb_bytes));
- addr_base = size_binop_loc (loc, PLUS_EXPR, addr_base,
- TYPE_SIZE_UNIT (TREE_TYPE (DR_REF (dr))));
- }
-
- return fold_build_pointer_plus_loc (loc, DR_BASE_ADDRESS (dr), addr_base);
-}
-
/* If VAL memory representation contains the same value in all bytes,
return that value, otherwise return -1.
E.g. for 0x24242424 return 0x24, for IEEE double
@@ -995,27 +968,23 @@ static void
generate_memset_builtin (struct loop *loop, partition *partition)
{
gimple_stmt_iterator gsi;
- gimple *stmt, *fn_call;
tree mem, fn, nb_bytes;
- location_t loc;
tree val;
-
- stmt = DR_STMT (partition->main_dr);
- loc = gimple_location (stmt);
+ struct builtin_info *builtin = partition->builtin;
+ gimple *fn_call;
/* The new statements will be placed before LOOP. */
gsi = gsi_last_bb (loop_preheader_edge (loop)->src);
- nb_bytes = build_size_arg_loc (loc, partition->main_dr, partition->niter,
- partition->plus_one);
+ nb_bytes = builtin->size;
nb_bytes = force_gimple_operand_gsi (&gsi, nb_bytes, true, NULL_TREE,
false, GSI_CONTINUE_LINKING);
- mem = build_addr_arg_loc (loc, partition->main_dr, nb_bytes);
+ mem = builtin->dst_base;
mem = force_gimple_operand_gsi (&gsi, mem, true, NULL_TREE,
false, GSI_CONTINUE_LINKING);
/* This exactly matches the pattern recognition in classify_partition. */
- val = gimple_assign_rhs1 (stmt);
+ val = gimple_assign_rhs1 (DR_STMT (builtin->dst_dr));
/* Handle constants like 0x15151515 and similarly
floating point constants etc. where all bytes are the same. */
int bytev = const_with_all_bytes_same (val);
@@ -1051,23 +1020,19 @@ static void
generate_memcpy_builtin (struct loop *loop, partition *partition)
{
gimple_stmt_iterator gsi;
- gimple *stmt, *fn_call;
+ gimple *fn_call;
tree dest, src, fn, nb_bytes;
- location_t loc;
enum built_in_function kind;
-
- stmt = DR_STMT (partition->main_dr);
- loc = gimple_location (stmt);
+ struct builtin_info *builtin = partition->builtin;
/* The new statements will be placed before LOOP. */
gsi = gsi_last_bb (loop_preheader_edge (loop)->src);
- nb_bytes = build_size_arg_loc (loc, partition->main_dr, partition->niter,
- partition->plus_one);
+ nb_bytes = builtin->size;
nb_bytes = force_gimple_operand_gsi (&gsi, nb_bytes, true, NULL_TREE,
false, GSI_CONTINUE_LINKING);
- dest = build_addr_arg_loc (loc, partition->main_dr, nb_bytes);
- src = build_addr_arg_loc (loc, partition->secondary_dr, nb_bytes);
+ dest = builtin->dst_base;
+ src = builtin->src_base;
if (partition->kind == PKIND_MEMCPY
|| ! ptr_derefs_may_alias_p (dest, src))
kind = BUILT_IN_MEMCPY;
@@ -1318,69 +1283,22 @@ build_rdg_partition_for_vertex (struct graph *rdg, int v)
return partition;
}
-/* Classifies the builtin kind we can generate for PARTITION of RDG and LOOP.
- For the moment we detect memset, memcpy and memmove patterns. Bitmap
- STMT_IN_ALL_PARTITIONS contains statements belonging to all partitions. */
+/* Given PARTITION of RDG, record single load/store data references for
+ builtin partition in SRC_DR/DST_DR, return false if there is no such
+ data references. */
-static void
-classify_partition (loop_p loop, struct graph *rdg, partition *partition,
- bitmap stmt_in_all_partitions)
+static bool
+find_single_drs (struct graph *rdg, partition *partition,
+ data_reference_p *dst_dr, data_reference_p *src_dr)
{
- bitmap_iterator bi;
unsigned i;
- tree nb_iter;
- data_reference_p single_load, single_store;
- bool volatiles_p = false, plus_one = false, has_reduction = false;
-
- partition->kind = PKIND_NORMAL;
- partition->main_dr = NULL;
- partition->secondary_dr = NULL;
- partition->niter = NULL_TREE;
- partition->plus_one = false;
-
- EXECUTE_IF_SET_IN_BITMAP (partition->stmts, 0, i, bi)
- {
- gimple *stmt = RDG_STMT (rdg, i);
-
- if (gimple_has_volatile_ops (stmt))
- volatiles_p = true;
-
- /* If the stmt is not included by all partitions and there is uses
- outside of the loop, then mark the partition as reduction. */
- if (stmt_has_scalar_dependences_outside_loop (loop, stmt))
- {
- /* Due to limitation in the transform phase we have to fuse all
- reduction partitions. As a result, this could cancel valid
- loop distribution especially for loop that induction variable
- is used outside of loop. To workaround this issue, we skip
- marking partition as reudction if the reduction stmt belongs
- to all partitions. In such case, reduction will be computed
- correctly no matter how partitions are fused/distributed. */
- if (!bitmap_bit_p (stmt_in_all_partitions, i))
- {
- partition->reduction_p = true;
- return;
- }
- has_reduction = true;
- }
- }
-
- /* Perform general partition disqualification for builtins. */
- if (volatiles_p
- /* Simple workaround to prevent classifying the partition as builtin
- if it contains any use outside of loop. */
- || has_reduction
- || !flag_tree_loop_distribute_patterns)
- return;
+ data_reference_p single_ld = NULL, single_st = NULL;
+ bitmap_iterator bi;
- /* Detect memset and memcpy. */
- single_load = NULL;
- single_store = NULL;
EXECUTE_IF_SET_IN_BITMAP (partition->stmts, 0, i, bi)
{
gimple *stmt = RDG_STMT (rdg, i);
data_reference_p dr;
- unsigned j;
if (gimple_code (stmt) == GIMPLE_PHI)
continue;
@@ -1391,123 +1309,316 @@ classify_partition (loop_p loop, struct graph *rdg, partition *partition,
/* Otherwise just regular loads/stores. */
if (!gimple_assign_single_p (stmt))
- return;
+ return false;
/* But exactly one store and/or load. */
- for (j = 0; RDG_DATAREFS (rdg, i).iterate (j, &dr); ++j)
+ for (unsigned j = 0; RDG_DATAREFS (rdg, i).iterate (j, &dr); ++j)
{
tree type = TREE_TYPE (DR_REF (dr));
/* The memset, memcpy and memmove library calls are only
able to deal with generic address space. */
if (!ADDR_SPACE_GENERIC_P (TYPE_ADDR_SPACE (type)))
- return;
+ return false;
if (DR_IS_READ (dr))
{
- if (single_load != NULL)
- return;
- single_load = dr;
+ if (single_ld != NULL)
+ return false;
+ single_ld = dr;
}
else
{
- if (single_store != NULL)
- return;
- single_store = dr;
+ if (single_st != NULL)
+ return false;
+ single_st = dr;
}
}
}
- if (!single_store)
- return;
+ if (!single_st)
+ return false;
+
+ /* Bail out if this is a bitfield memory reference. */
+ if (TREE_CODE (DR_REF (single_st)) == COMPONENT_REF
+ && DECL_BIT_FIELD (TREE_OPERAND (DR_REF (single_st), 1)))
+ return false;
- /* TODO: We don't support memset/memcpy distribution for loop nest yet. */
- if (loop->inner)
+ /* Data reference must be executed exactly once per iteration. */
+ basic_block bb_st = gimple_bb (DR_STMT (single_st));
+ struct loop *inner = bb_st->loop_father;
+ if (!dominated_by_p (CDI_DOMINATORS, inner->latch, bb_st))
+ return false;
+
+ if (single_ld)
{
- basic_block bb = gimple_bb (DR_STMT (single_store));
+ gimple *store = DR_STMT (single_st), *load = DR_STMT (single_ld);
+ /* Direct aggregate copy or via an SSA name temporary. */
+ if (load != store
+ && gimple_assign_lhs (load) != gimple_assign_rhs1 (store))
+ return false;
- if (bb->loop_father != loop)
- return;
+ /* Bail out if this is a bitfield memory reference. */
+ if (TREE_CODE (DR_REF (single_ld)) == COMPONENT_REF
+ && DECL_BIT_FIELD (TREE_OPERAND (DR_REF (single_ld), 1)))
+ return false;
+
+ /* Load and store must be in the same loop nest. */
+ basic_block bb_ld = gimple_bb (DR_STMT (single_ld));
+ if (inner != bb_ld->loop_father)
+ return false;
+
+ /* Data reference must be executed exactly once per iteration. */
+ if (!dominated_by_p (CDI_DOMINATORS, inner->latch, bb_ld))
+ return false;
- if (single_load)
+ edge e = single_exit (inner);
+ bool dom_ld = dominated_by_p (CDI_DOMINATORS, e->src, bb_ld);
+ bool dom_st = dominated_by_p (CDI_DOMINATORS, e->src, bb_st);
+ if (dom_ld != dom_st)
+ return false;
+ }
+
+ *src_dr = single_ld;
+ *dst_dr = single_st;
+ return true;
+}
+
+/* Given data reference DR in LOOP_NEST, this function checks the enclosing
+ loops from inner to outer to see if loop's step equals to access size at
+ each level of loop. Return true if yes; record access base and size in
+ BASE and SIZE; save loop's step at each level of loop in STEPS if it is
+ not null. For example:
+
+ int arr[100][100][100];
+ for (i = 0; i < 100; i++) ;steps[2] = 40000
+ for (j = 100; j > 0; j--) ;steps[1] = -400
+ for (k = 0; k < 100; k++) ;steps[0] = 4
+ arr[i][j - 1][k] = 0; ;base = &arr, size = 4000000. */
+
+static bool
+compute_access_range (loop_p loop_nest, data_reference_p dr, tree *base,
+ tree *size, vec<tree> *steps = NULL)
+{
+ location_t loc = gimple_location (DR_STMT (dr));
+ basic_block bb = gimple_bb (DR_STMT (dr));
+ struct loop *loop = bb->loop_father;
+ tree ref = DR_REF (dr);
+ tree access_base = build_fold_addr_expr (ref);
+ tree access_size = TYPE_SIZE_UNIT (TREE_TYPE (ref));
+
+ do {
+ tree scev_fn = analyze_scalar_evolution (loop, access_base);
+ if (TREE_CODE (scev_fn) != POLYNOMIAL_CHREC)
+ return false;
+
+ access_base = CHREC_LEFT (scev_fn);
+ if (tree_contains_chrecs (access_base, NULL))
+ return false;
+
+ tree scev_step = CHREC_RIGHT (scev_fn);
+ /* Only support constant steps. */
+ if (TREE_CODE (scev_step) != INTEGER_CST)
+ return false;
+
+ enum ev_direction access_dir = scev_direction (scev_fn);
+ if (access_dir == EV_DIR_UNKNOWN)
+ return false;
+
+ if (steps != NULL)
+ steps->safe_push (scev_step);
+
+ scev_step = fold_convert_loc (loc, sizetype, scev_step);
+ /* Compute absolute value of scev step. */
+ if (access_dir == EV_DIR_DECREASES)
+ scev_step = fold_build1_loc (loc, NEGATE_EXPR, sizetype, scev_step);
+
+ /* At each level of loop, scev step must equal to access size. In other
+ words, DR must access consecutive memory between loop iterations. */
+ if (!operand_equal_p (scev_step, access_size, 0))
+ return false;
+
+ /* Compute DR's execution times in loop. */
+ tree niters = number_of_latch_executions (loop);
+ niters = fold_convert_loc (loc, sizetype, niters);
+ if (dominated_by_p (CDI_DOMINATORS, single_exit (loop)->src, bb))
+ niters = size_binop_loc (loc, PLUS_EXPR, niters, size_one_node);
+
+ /* Compute DR's overall access size in loop. */
+ access_size = fold_build2_loc (loc, MULT_EXPR, sizetype,
+ niters, scev_step);
+ /* Adjust base address in case of negative step. */
+ if (access_dir == EV_DIR_DECREASES)
{
- bb = gimple_bb (DR_STMT (single_load));
- if (bb->loop_father != loop)
- return;
+ tree adj = fold_build2_loc (loc, MINUS_EXPR, sizetype,
+ scev_step, access_size);
+ access_base = fold_build_pointer_plus_loc (loc, access_base, adj);
}
+ } while (loop != loop_nest && (loop = loop_outer (loop)) != NULL);
+
+ *base = access_base;
+ *size = access_size;
+ return true;
+}
+
+/* Allocate and return builtin struct. Record information like DST_DR,
+ SRC_DR, DST_BASE, SRC_BASE and SIZE in the allocated struct. */
+
+static struct builtin_info *
+alloc_builtin (data_reference_p dst_dr, data_reference_p src_dr,
+ tree dst_base, tree src_base, tree size)
+{
+ struct builtin_info *builtin = XNEW (struct builtin_info);
+ builtin->dst_dr = dst_dr;
+ builtin->src_dr = src_dr;
+ builtin->dst_base = dst_base;
+ builtin->src_base = src_base;
+ builtin->size = size;
+ return builtin;
+}
+
+/* Given data reference DR in loop nest LOOP, classify if it forms builtin
+ memset call. */
+
+static void
+classify_builtin_st (loop_p loop, partition *partition, data_reference_p dr)
+{
+ gimple *stmt = DR_STMT (dr);
+ tree base, size, rhs = gimple_assign_rhs1 (stmt);
+
+ if (const_with_all_bytes_same (rhs) == -1
+ && (!INTEGRAL_TYPE_P (TREE_TYPE (rhs))
+ || (TYPE_MODE (TREE_TYPE (rhs))
+ != TYPE_MODE (unsigned_char_type_node))))
+ return;
+
+ if (TREE_CODE (rhs) == SSA_NAME
+ && !SSA_NAME_IS_DEFAULT_DEF (rhs)
+ && flow_bb_inside_loop_p (loop, gimple_bb (SSA_NAME_DEF_STMT (rhs))))
+ return;
+
+ if (!compute_access_range (loop, dr, &base, &size))
+ return;
+
+ partition->builtin = alloc_builtin (dr, NULL, base, NULL_TREE, size);
+ partition->kind = PKIND_MEMSET;
+}
+
+/* Given data references DST_DR and SRC_DR in loop nest LOOP and RDG, classify
+ if it forms builtin memcpy or memmove call. */
+
+static void
+classify_builtin_ldst (loop_p loop, struct graph *rdg, partition *partition,
+ data_reference_p dst_dr, data_reference_p src_dr)
+{
+ tree base, size, src_base, src_size;
+ auto_vec<tree> dst_steps, src_steps;
+
+ /* Compute access range of both load and store. They much have the same
+ access size. */
+ if (!compute_access_range (loop, dst_dr, &base, &size, &dst_steps)
+ || !compute_access_range (loop, src_dr, &src_base, &src_size, &src_steps)
+ || !operand_equal_p (size, src_size, 0))
+ return;
+
+ /* Load and store in loop nest must access memory in the same way, i.e,
+ their must have the same steps in each loop of the nest. */
+ if (dst_steps.length () != src_steps.length ())
+ return;
+ for (unsigned i = 0; i < dst_steps.length (); ++i)
+ if (!operand_equal_p (dst_steps[i], src_steps[i], 0))
+ return;
+
+ /* Now check that if there is a dependence. */
+ ddr_p ddr = get_data_dependence (rdg, src_dr, dst_dr);
+
+ /* Classify as memcpy if no dependence between load and store. */
+ if (DDR_ARE_DEPENDENT (ddr) == chrec_known)
+ {
+ partition->builtin = alloc_builtin (dst_dr, src_dr, base, src_base, size);
+ partition->kind = PKIND_MEMCPY;
+ return;
}
- nb_iter = number_of_latch_executions (loop);
- gcc_assert (nb_iter && nb_iter != chrec_dont_know);
- if (dominated_by_p (CDI_DOMINATORS, single_exit (loop)->src,
- gimple_bb (DR_STMT (single_store))))
- plus_one = true;
+ /* Can't do memmove in case of unknown dependence or dependence without
+ classical distance vector. */
+ if (DDR_ARE_DEPENDENT (ddr) == chrec_dont_know
+ || DDR_NUM_DIST_VECTS (ddr) == 0)
+ return;
- if (single_store && !single_load)
+ unsigned i;
+ lambda_vector dist_v;
+ int num_lev = (DDR_LOOP_NEST (ddr)).length ();
+ FOR_EACH_VEC_ELT (DDR_DIST_VECTS (ddr), i, dist_v)
{
- gimple *stmt = DR_STMT (single_store);
- tree rhs = gimple_assign_rhs1 (stmt);
- if (const_with_all_bytes_same (rhs) == -1
- && (!INTEGRAL_TYPE_P (TREE_TYPE (rhs))
- || (TYPE_MODE (TREE_TYPE (rhs))
- != TYPE_MODE (unsigned_char_type_node))))
+ unsigned dep_lev = dependence_level (dist_v, num_lev);
+ /* Can't do memmove if load depends on store. */
+ if (dep_lev > 0 && dist_v[dep_lev - 1] > 0 && !DDR_REVERSED_P (ddr))
return;
- if (TREE_CODE (rhs) == SSA_NAME
- && !SSA_NAME_IS_DEFAULT_DEF (rhs)
- && flow_bb_inside_loop_p (loop, gimple_bb (SSA_NAME_DEF_STMT (rhs))))
- return;
- if (!adjacent_dr_p (single_store)
- || !dominated_by_p (CDI_DOMINATORS,
- loop->latch, gimple_bb (stmt)))
- return;
- partition->kind = PKIND_MEMSET;
- partition->main_dr = single_store;
- partition->niter = nb_iter;
- partition->plus_one = plus_one;
}
- else if (single_store && single_load)
+
+ partition->builtin = alloc_builtin (dst_dr, src_dr, base, src_base, size);
+ partition->kind = PKIND_MEMMOVE;
+ return;
+}
+
+/* Classifies the builtin kind we can generate for PARTITION of RDG and LOOP.
+ For the moment we detect memset, memcpy and memmove patterns. Bitmap
+ STMT_IN_ALL_PARTITIONS contains statements belonging to all partitions. */
+
+static void
+classify_partition (loop_p loop, struct graph *rdg, partition *partition,
+ bitmap stmt_in_all_partitions)
+{
+ bitmap_iterator bi;
+ unsigned i;
+ data_reference_p single_ld = NULL, single_st = NULL;
+ bool volatiles_p = false, has_reduction = false;
+
+ EXECUTE_IF_SET_IN_BITMAP (partition->stmts, 0, i, bi)
{
- gimple *store = DR_STMT (single_store);
- gimple *load = DR_STMT (single_load);
- /* Direct aggregate copy or via an SSA name temporary. */
- if (load != store
- && gimple_assign_lhs (load) != gimple_assign_rhs1 (store))
- return;
- if (!adjacent_dr_p (single_store)
- || !adjacent_dr_p (single_load)
- || !operand_equal_p (DR_STEP (single_store),
- DR_STEP (single_load), 0)
- || !dominated_by_p (CDI_DOMINATORS,
- loop->latch, gimple_bb (store)))
- return;
- /* Now check that if there is a dependence this dependence is
- of a suitable form for memmove. */
- ddr_p ddr = get_data_dependence (rdg, single_load, single_store);
- if (DDR_ARE_DEPENDENT (ddr) == chrec_dont_know)
- return;
+ gimple *stmt = RDG_STMT (rdg, i);
- if (DDR_ARE_DEPENDENT (ddr) != chrec_known)
- {
- if (DDR_NUM_DIST_VECTS (ddr) == 0)
- return;
+ if (gimple_has_volatile_ops (stmt))
+ volatiles_p = true;
- lambda_vector dist_v;
- FOR_EACH_VEC_ELT (DDR_DIST_VECTS (ddr), i, dist_v)
+ /* If the stmt is not included by all partitions and there is uses
+ outside of the loop, then mark the partition as reduction. */
+ if (stmt_has_scalar_dependences_outside_loop (loop, stmt))
+ {
+ /* Due to limitation in the transform phase we have to fuse all
+ reduction partitions. As a result, this could cancel valid
+ loop distribution especially for loop that induction variable
+ is used outside of loop. To workaround this issue, we skip
+ marking partition as reudction if the reduction stmt belongs
+ to all partitions. In such case, reduction will be computed
+ correctly no matter how partitions are fused/distributed. */
+ if (!bitmap_bit_p (stmt_in_all_partitions, i))
{
- int dist = dist_v[index_in_loop_nest (loop->num,
- DDR_LOOP_NEST (ddr))];
- if (dist > 0 && !DDR_REVERSED_P (ddr))
- return;
+ partition->reduction_p = true;
+ return;
}
- partition->kind = PKIND_MEMMOVE;
+ has_reduction = true;
}
- else
- partition->kind = PKIND_MEMCPY;
- partition->main_dr = single_store;
- partition->secondary_dr = single_load;
- partition->niter = nb_iter;
- partition->plus_one = plus_one;
}
+
+ /* Perform general partition disqualification for builtins. */
+ if (volatiles_p
+ /* Simple workaround to prevent classifying the partition as builtin
+ if it contains any use outside of loop. */
+ || has_reduction
+ || !flag_tree_loop_distribute_patterns)
+ return;
+
+ /* Find single load/store data references for builtin partition. */
+ if (!find_single_drs (rdg, partition, &single_st, &single_ld))
+ return;
+
+ /* Classify the builtin kind. */
+ if (single_ld == NULL)
+ classify_builtin_st (loop, partition, single_st);
+ else
+ classify_builtin_ldst (loop, rdg, partition, single_st, single_ld);
}
/* Returns true when PARTITION1 and PARTITION2 access the same memory
--
1.9.1
