pg.ddx.io pgsql-hackers@postgresql.org mailing list archive help / color / mirror / Atom feed From: Nathan Bossart <nathandbossart@gmail.com>
To: Ankit Kumar Pandey <itsankitkp@gmail.com>
Cc: pgsql-hackers@lists.postgresql.org
Subject: Re: optimize several list functions with SIMD intrinsics
Date: Mon, 17 Apr 2023 13:42:50 -0700
Message-ID: <20230417204250.GA1347414@nathanxps13> (raw )
In-Reply-To: <468200fd-a039-5edc-4907-0104d0953f70@gmail.com >
References: <20230308002502.GA3378449@nathanxps13 >
<20230308185809.GA3552675@nathanxps13 >
<167852767890.628976.10354523915450248589.pgcf@coridan.postgresql.org >
<20230313214027.GB423713@nathanxps13 >
<7fc23473-7f10-5282-711e-34247d089f75@gmail.com >
<20230315162319.GA609684@nathanxps13 >
<468200fd-a039-5edc-4907-0104d0953f70@gmail.com >
Here is a new patch set. I've split it into two patches: one for the
64-bit functions, and one for the 32-bit functions. I've also added tests
for pg_lfind64/pg_lfind64_idx and deduplicated the code a bit.
--
Nathan Bossart
Amazon Web Services: https://aws.amazon.com
Attachments: download all (2 files, .tar.gz)
v3-0001-speed-up-list_member_ptr-and-list_delete_ptr-with.patch (text/x-diff, 14.5K) download
From 7dbbf61e8a2546a73413c3768a49da318f7de7f5 Mon Sep 17 00:00:00 2001
From: Nathan Bossart <nathandbossart@gmail.com>
Date: Mon, 10 Apr 2023 09:10:47 -0700
Subject: [PATCH v3 1/2] speed up list_member_ptr and list_delete_ptr with SIMD
---
src/backend/nodes/list.c | 35 ++++++
src/include/port/pg_lfind.h | 112 ++++++++++++++++++
src/include/port/simd.h | 96 ++++++++++++++-
.../test_lfind/expected/test_lfind.out | 12 ++
.../modules/test_lfind/sql/test_lfind.sql | 2 +
.../modules/test_lfind/test_lfind--1.0.sql | 8 ++
src/test/modules/test_lfind/test_lfind.c | 62 ++++++++++
7 files changed, 324 insertions(+), 3 deletions(-)
diff --git a/src/backend/nodes/list.c b/src/backend/nodes/list.c
index a709d23ef1..92bc48de17 100644
--- a/src/backend/nodes/list.c
+++ b/src/backend/nodes/list.c
@@ -19,6 +19,7 @@
#include "nodes/pg_list.h"
#include "port/pg_bitutils.h"
+#include "port/pg_lfind.h"
#include "utils/memdebug.h"
#include "utils/memutils.h"
@@ -680,11 +681,15 @@ list_member(const List *list, const void *datum)
bool
list_member_ptr(const List *list, const void *datum)
{
+#ifdef USE_NO_SIMD
const ListCell *cell;
+#endif
Assert(IsPointerList(list));
check_list_invariants(list);
+#ifdef USE_NO_SIMD
+
foreach(cell, list)
{
if (lfirst(cell) == datum)
@@ -692,6 +697,18 @@ list_member_ptr(const List *list, const void *datum)
}
return false;
+
+#else
+
+ Assert(sizeof(ListCell) == 8);
+ Assert(sizeof(void *) == 8);
+
+ if (list == NIL)
+ return false;
+
+ return pg_lfind64((uint64) datum, (uint64 *) list->elements, list->length);
+
+#endif
}
/*
@@ -875,12 +892,30 @@ list_delete_ptr(List *list, void *datum)
Assert(IsPointerList(list));
check_list_invariants(list);
+#ifdef USE_NO_SIMD
+
foreach(cell, list)
{
if (lfirst(cell) == datum)
return list_delete_cell(list, cell);
}
+#else
+
+ Assert(sizeof(ListCell) == 8);
+ Assert(sizeof(void *) == 8);
+
+ if (list == NIL)
+ return NIL;
+
+ cell = (ListCell *) pg_lfind64_idx((uint64) datum,
+ (uint64 *) list->elements,
+ list->length);
+ if (cell != NULL)
+ return list_delete_cell(list, cell);
+
+#endif
+
/* Didn't find a match: return the list unmodified */
return list;
}
diff --git a/src/include/port/pg_lfind.h b/src/include/port/pg_lfind.h
index 59aa8245ed..d08ad91ae8 100644
--- a/src/include/port/pg_lfind.h
+++ b/src/include/port/pg_lfind.h
@@ -177,4 +177,116 @@ pg_lfind32(uint32 key, uint32 *base, uint32 nelem)
return false;
}
+/*
+ * pg_lfind64_internal
+ *
+ * Workhorse for pg_lfind64 and pg_lfind64_idx.
+ */
+static inline bool
+pg_lfind64_internal(uint64 key, uint64 *base, uint32 nelem, uint32 *i)
+{
+#ifdef USE_NO_SIMD
+
+ *i = 0;
+
+#else
+
+ /*
+ * For better instruction-level parallelism, each loop iteration operates
+ * on a block of four registers.
+ */
+ const Vector64 keys = vector64_broadcast(key); /* load copies of key */
+ const uint32 nelem_per_vector = sizeof(Vector64) / sizeof(uint64);
+ const uint32 nelem_per_iteration = 4 * nelem_per_vector;
+
+ /* round down to multiple of elements per iteration */
+ const uint32 tail_idx = nelem & ~(nelem_per_iteration - 1);
+
+ for (*i = 0; *i < tail_idx; *i += nelem_per_iteration)
+ {
+ Vector64 vals1,
+ vals2,
+ vals3,
+ vals4,
+ result1,
+ result2,
+ result3,
+ result4,
+ tmp1,
+ tmp2,
+ result;
+
+ /* load the next block into 4 registers */
+ vector64_load(&vals1, &base[*i]);
+ vector64_load(&vals2, &base[*i + nelem_per_vector]);
+ vector64_load(&vals3, &base[*i + nelem_per_vector * 2]);
+ vector64_load(&vals4, &base[*i + nelem_per_vector * 3]);
+
+ /* compare each value to the key */
+ result1 = vector64_eq(keys, vals1);
+ result2 = vector64_eq(keys, vals2);
+ result3 = vector64_eq(keys, vals3);
+ result4 = vector64_eq(keys, vals4);
+
+ /* combine the results into a single variable */
+ tmp1 = vector64_or(result1, result2);
+ tmp2 = vector64_or(result3, result4);
+ result = vector64_or(tmp1, tmp2);
+
+ /* see if there was a match */
+ if (vector64_is_highbit_set(result))
+ return true;
+ }
+#endif /* ! USE_NO_SIMD */
+
+ return false;
+}
+
+/*
+ * pg_lfind64
+ *
+ * Return true if there is an element in 'base' that equals 'key', otherwise
+ * return false.
+ */
+static inline bool
+pg_lfind64(uint64 key, uint64 *base, uint32 nelem)
+{
+ uint32 i = 0;
+
+ if (pg_lfind64_internal(key, base, nelem, &i))
+ return true;
+
+ /* Process the remaining elements one at a time. */
+ for (; i < nelem; i++)
+ {
+ if (key == base[i])
+ return true;
+ }
+
+ return false;
+}
+
+/*
+ * pg_lfind64_idx
+ *
+ * Return the address of the first element in 'base' that equals 'key', or NULL
+ * if no match is found.
+ */
+static inline uint64 *
+pg_lfind64_idx(uint64 key, uint64 *base, uint32 nelem)
+{
+ uint32 i = 0;
+
+ (void) pg_lfind64_internal(key, base, nelem, &i);
+
+ /* Process the remaining elements one at a time. */
+ for (; i < nelem; i++)
+ {
+ if (key == base[i])
+ return &base[i];
+ }
+
+ return NULL;
+}
+
#endif /* PG_LFIND_H */
diff --git a/src/include/port/simd.h b/src/include/port/simd.h
index 1fa6c3bc6c..b851d3d89d 100644
--- a/src/include/port/simd.h
+++ b/src/include/port/simd.h
@@ -32,6 +32,7 @@
#define USE_SSE2
typedef __m128i Vector8;
typedef __m128i Vector32;
+typedef __m128i Vector64;
#elif defined(__aarch64__) && defined(__ARM_NEON)
/*
@@ -46,15 +47,16 @@ typedef __m128i Vector32;
#define USE_NEON
typedef uint8x16_t Vector8;
typedef uint32x4_t Vector32;
+typedef uint64x2_t Vector64;
#else
/*
* If no SIMD instructions are available, we can in some cases emulate vector
* operations using bitwise operations on unsigned integers. Note that many
* of the functions in this file presently do not have non-SIMD
- * implementations. In particular, none of the functions involving Vector32
- * are implemented without SIMD since it's likely not worthwhile to represent
- * two 32-bit integers using a uint64.
+ * implementations. For example, none of the functions involving Vector32 are
+ * implemented without SIMD since it's likely not worthwhile to represent two
+ * 32-bit integers using a uint64.
*/
#define USE_NO_SIMD
typedef uint64 Vector8;
@@ -64,12 +66,14 @@ typedef uint64 Vector8;
static inline void vector8_load(Vector8 *v, const uint8 *s);
#ifndef USE_NO_SIMD
static inline void vector32_load(Vector32 *v, const uint32 *s);
+static inline void vector64_load(Vector64 *v, const uint64 *s);
#endif
/* assignment operations */
static inline Vector8 vector8_broadcast(const uint8 c);
#ifndef USE_NO_SIMD
static inline Vector32 vector32_broadcast(const uint32 c);
+static inline Vector64 vector64_broadcast(const uint64 c);
#endif
/* element-wise comparisons to a scalar */
@@ -79,12 +83,15 @@ static inline bool vector8_has_le(const Vector8 v, const uint8 c);
static inline bool vector8_is_highbit_set(const Vector8 v);
#ifndef USE_NO_SIMD
static inline bool vector32_is_highbit_set(const Vector32 v);
+static inline bool vector64_is_highbit_set(const Vector64 v);
#endif
/* arithmetic operations */
static inline Vector8 vector8_or(const Vector8 v1, const Vector8 v2);
#ifndef USE_NO_SIMD
static inline Vector32 vector32_or(const Vector32 v1, const Vector32 v2);
+static inline Vector64 vector64_or(const Vector64 v1, const Vector64 v2);
+static inline Vector32 vector32_and(const Vector32 v1, const Vector32 v2);
static inline Vector8 vector8_ssub(const Vector8 v1, const Vector8 v2);
#endif
@@ -97,6 +104,7 @@ static inline Vector8 vector8_ssub(const Vector8 v1, const Vector8 v2);
#ifndef USE_NO_SIMD
static inline Vector8 vector8_eq(const Vector8 v1, const Vector8 v2);
static inline Vector32 vector32_eq(const Vector32 v1, const Vector32 v2);
+static inline Vector64 vector64_eq(const Vector64 v1, const Vector64 v2);
#endif
/*
@@ -126,6 +134,18 @@ vector32_load(Vector32 *v, const uint32 *s)
}
#endif /* ! USE_NO_SIMD */
+#ifndef USE_NO_SIMD
+static inline void
+vector64_load(Vector64 *v, const uint64 *s)
+{
+#ifdef USE_SSE2
+ *v = _mm_loadu_si128((const __m128i *) s);
+#elif defined(USE_NEON)
+ *v = vld1q_u64((const uint64_t *) s);
+#endif
+}
+#endif /* ! USE_NO_SIMD */
+
/*
* Create a vector with all elements set to the same value.
*/
@@ -153,6 +173,18 @@ vector32_broadcast(const uint32 c)
}
#endif /* ! USE_NO_SIMD */
+#ifndef USE_NO_SIMD
+static inline Vector64
+vector64_broadcast(const uint64 c)
+{
+#ifdef USE_SSE2
+ return _mm_set1_epi64x(c);
+#elif defined(USE_NEON)
+ return vdupq_n_u64(c);
+#endif
+}
+#endif /* ! USE_NO_SIMD */
+
/*
* Return true if any elements in the vector are equal to the given scalar.
*/
@@ -299,6 +331,23 @@ vector32_is_highbit_set(const Vector32 v)
}
#endif /* ! USE_NO_SIMD */
+/*
+ * Exactly like vector8_is_highbit_set except for the input type, so it
+ * looks at each byte separately. See the comment above
+ * vector32_is_highbit_set for more information.
+ */
+#ifndef USE_NO_SIMD
+static inline bool
+vector64_is_highbit_set(const Vector64 v)
+{
+#if defined(USE_NEON)
+ return vector8_is_highbit_set((Vector8) v);
+#else
+ return vector8_is_highbit_set(v);
+#endif
+}
+#endif /* ! USE_NO_SIMD */
+
/*
* Return the bitwise OR of the inputs
*/
@@ -326,6 +375,30 @@ vector32_or(const Vector32 v1, const Vector32 v2)
}
#endif /* ! USE_NO_SIMD */
+#ifndef USE_NO_SIMD
+static inline Vector64
+vector64_or(const Vector64 v1, const Vector64 v2)
+{
+#ifdef USE_SSE2
+ return _mm_or_si128(v1, v2);
+#elif defined(USE_NEON)
+ return vorrq_u64(v1, v2);
+#endif
+}
+#endif /* ! USE_NO_SIMD */
+
+#ifndef USE_NO_SIMD
+static inline Vector32
+vector32_and(const Vector32 v1, const Vector32 v2)
+{
+#ifdef USE_SSE2
+ return _mm_and_si128(v1, v2);
+#elif defined(USE_NEON)
+ return vandq_u32(v1, v2);
+#endif
+}
+#endif /* ! USE_NO_SIMD */
+
/*
* Return the result of subtracting the respective elements of the input
* vectors using saturation (i.e., if the operation would yield a value less
@@ -372,4 +445,21 @@ vector32_eq(const Vector32 v1, const Vector32 v2)
}
#endif /* ! USE_NO_SIMD */
+#ifndef USE_NO_SIMD
+static inline Vector64
+vector64_eq(const Vector64 v1, const Vector64 v2)
+{
+#ifdef USE_SSE2
+ /* We have to work around SSE2's lack of _mm_cmpeq_epi64. */
+ const Vector32 cmp = vector32_eq(v1, v2);
+ const Vector32 hi = _mm_shuffle_epi32(cmp, _MM_SHUFFLE(3, 3, 1, 1));
+ const Vector32 lo = _mm_shuffle_epi32(cmp, _MM_SHUFFLE(2, 2, 0, 0));
+
+ return vector32_and(hi, lo);
+#elif defined(USE_NEON)
+ return vceqq_u64(v1, v2);
+#endif
+}
+#endif /* ! USE_NO_SIMD */
+
#endif /* SIMD_H */
diff --git a/src/test/modules/test_lfind/expected/test_lfind.out b/src/test/modules/test_lfind/expected/test_lfind.out
index 1d4b14e703..6488c7f700 100644
--- a/src/test/modules/test_lfind/expected/test_lfind.out
+++ b/src/test/modules/test_lfind/expected/test_lfind.out
@@ -22,3 +22,15 @@ SELECT test_lfind32();
(1 row)
+SELECT test_lfind64();
+ test_lfind64
+--------------
+
+(1 row)
+
+SELECT test_lfind64_idx();
+ test_lfind64_idx
+------------------
+
+(1 row)
+
diff --git a/src/test/modules/test_lfind/sql/test_lfind.sql b/src/test/modules/test_lfind/sql/test_lfind.sql
index 766c640831..0b5b6eea9e 100644
--- a/src/test/modules/test_lfind/sql/test_lfind.sql
+++ b/src/test/modules/test_lfind/sql/test_lfind.sql
@@ -8,3 +8,5 @@ CREATE EXTENSION test_lfind;
SELECT test_lfind8();
SELECT test_lfind8_le();
SELECT test_lfind32();
+SELECT test_lfind64();
+SELECT test_lfind64_idx();
diff --git a/src/test/modules/test_lfind/test_lfind--1.0.sql b/src/test/modules/test_lfind/test_lfind--1.0.sql
index 81801926ae..55c5fd2087 100644
--- a/src/test/modules/test_lfind/test_lfind--1.0.sql
+++ b/src/test/modules/test_lfind/test_lfind--1.0.sql
@@ -3,6 +3,14 @@
-- complain if script is sourced in psql, rather than via CREATE EXTENSION
\echo Use "CREATE EXTENSION test_lfind" to load this file. \quit
+CREATE FUNCTION test_lfind64()
+ RETURNS pg_catalog.void
+ AS 'MODULE_PATHNAME' LANGUAGE C;
+
+CREATE FUNCTION test_lfind64_idx()
+ RETURNS pg_catalog.void
+ AS 'MODULE_PATHNAME' LANGUAGE C;
+
CREATE FUNCTION test_lfind32()
RETURNS pg_catalog.void
AS 'MODULE_PATHNAME' LANGUAGE C;
diff --git a/src/test/modules/test_lfind/test_lfind.c b/src/test/modules/test_lfind/test_lfind.c
index e2e8b7389f..906e40300e 100644
--- a/src/test/modules/test_lfind/test_lfind.c
+++ b/src/test/modules/test_lfind/test_lfind.c
@@ -146,3 +146,65 @@ test_lfind32(PG_FUNCTION_ARGS)
PG_RETURN_VOID();
}
+
+PG_FUNCTION_INFO_V1(test_lfind64);
+Datum
+test_lfind64(PG_FUNCTION_ARGS)
+{
+ uint64 test_array[TEST_ARRAY_SIZE] = {0};
+
+ test_array[8] = 1;
+ test_array[64] = 2;
+ test_array[TEST_ARRAY_SIZE - 1] = 3;
+
+ if (pg_lfind64(1, test_array, 4))
+ elog(ERROR, "pg_lfind64() found nonexistent element");
+ if (!pg_lfind64(1, test_array, TEST_ARRAY_SIZE))
+ elog(ERROR, "pg_lfind64() did not find existing element");
+
+ if (pg_lfind64(2, test_array, 32))
+ elog(ERROR, "pg_lfind64() found nonexistent element");
+ if (!pg_lfind64(2, test_array, TEST_ARRAY_SIZE))
+ elog(ERROR, "pg_lfind64() did not find existing element");
+
+ if (pg_lfind64(3, test_array, 96))
+ elog(ERROR, "pg_lfind64() found nonexistent element");
+ if (!pg_lfind64(3, test_array, TEST_ARRAY_SIZE))
+ elog(ERROR, "pg_lfind64() did not find existing element");
+
+ if (pg_lfind64(4, test_array, TEST_ARRAY_SIZE))
+ elog(ERROR, "pg_lfind64() found nonexistent element");
+
+ PG_RETURN_VOID();
+}
+
+PG_FUNCTION_INFO_V1(test_lfind64_idx);
+Datum
+test_lfind64_idx(PG_FUNCTION_ARGS)
+{
+ uint64 test_array[TEST_ARRAY_SIZE] = {0};
+
+ test_array[8] = 1;
+ test_array[64] = 2;
+ test_array[TEST_ARRAY_SIZE - 1] = 3;
+
+ if (pg_lfind64_idx(1, test_array, 4) != NULL)
+ elog(ERROR, "pg_lfind64_idx() found nonexistent element");
+ if (pg_lfind64_idx(1, test_array, TEST_ARRAY_SIZE) != &test_array[8])
+ elog(ERROR, "pg_lfind64_idx() did not find existing element");
+
+ if (pg_lfind64_idx(2, test_array, 32) != NULL)
+ elog(ERROR, "pg_lfind6_idx4() found nonexistent element");
+ if (pg_lfind64_idx(2, test_array, TEST_ARRAY_SIZE) != &test_array[64])
+ elog(ERROR, "pg_lfind64_idx() did not find existing element");
+
+ if (pg_lfind64_idx(3, test_array, 96) != NULL)
+ elog(ERROR, "pg_lfind64_idx() found nonexistent element");
+ if (pg_lfind64_idx(3, test_array, TEST_ARRAY_SIZE) != &test_array[TEST_ARRAY_SIZE - 1])
+ elog(ERROR, "pg_lfind64_idx() did not find existing element");
+
+ if (pg_lfind64_idx(4, test_array, TEST_ARRAY_SIZE) != NULL)
+ elog(ERROR, "pg_lfind64_idx() found nonexistent element");
+
+ PG_RETURN_VOID();
+}
--
2.25.1
v3-0002-speed-up-several-functions-for-lists-with-inline-.patch (text/x-diff, 6.4K) download
From ccb3d6c072899063bc6e47388ef9a222a19be324 Mon Sep 17 00:00:00 2001
From: Nathan Bossart <nathandbossart@gmail.com>
Date: Mon, 17 Apr 2023 12:29:10 -0700
Subject: [PATCH v3 2/2] speed up several functions for lists with inline
32-bit data using SIMD
---
src/backend/nodes/list.c | 192 +++++++++++++++++++++++++++++++--------
1 file changed, 155 insertions(+), 37 deletions(-)
diff --git a/src/backend/nodes/list.c b/src/backend/nodes/list.c
index 92bc48de17..fa06caf553 100644
--- a/src/backend/nodes/list.c
+++ b/src/backend/nodes/list.c
@@ -57,6 +57,9 @@
#define IsOidList(l) ((l) == NIL || IsA((l), OidList))
#define IsXidList(l) ((l) == NIL || IsA((l), XidList))
+static inline ListCell *list_member_inline_internal_idx(const List *list, uint32 datum);
+static inline bool list_member_inline_internal(const List *list, uint32 datum);
+
#ifdef USE_ASSERT_CHECKING
/*
* Check that the specified List is valid (so far as we can tell).
@@ -717,18 +720,10 @@ list_member_ptr(const List *list, const void *datum)
bool
list_member_int(const List *list, int datum)
{
- const ListCell *cell;
-
Assert(IsIntegerList(list));
check_list_invariants(list);
- foreach(cell, list)
- {
- if (lfirst_int(cell) == datum)
- return true;
- }
-
- return false;
+ return list_member_inline_internal(list, datum);
}
/*
@@ -737,18 +732,10 @@ list_member_int(const List *list, int datum)
bool
list_member_oid(const List *list, Oid datum)
{
- const ListCell *cell;
-
Assert(IsOidList(list));
check_list_invariants(list);
- foreach(cell, list)
- {
- if (lfirst_oid(cell) == datum)
- return true;
- }
-
- return false;
+ return list_member_inline_internal(list, datum);
}
/*
@@ -757,18 +744,10 @@ list_member_oid(const List *list, Oid datum)
bool
list_member_xid(const List *list, TransactionId datum)
{
- const ListCell *cell;
-
Assert(IsXidList(list));
check_list_invariants(list);
- foreach(cell, list)
- {
- if (lfirst_xid(cell) == datum)
- return true;
- }
-
- return false;
+ return list_member_inline_internal(list, datum);
}
/*
@@ -929,11 +908,9 @@ list_delete_int(List *list, int datum)
Assert(IsIntegerList(list));
check_list_invariants(list);
- foreach(cell, list)
- {
- if (lfirst_int(cell) == datum)
- return list_delete_cell(list, cell);
- }
+ cell = list_member_inline_internal_idx(list, datum);
+ if (cell != NULL)
+ return list_delete_cell(list, cell);
/* Didn't find a match: return the list unmodified */
return list;
@@ -948,11 +925,9 @@ list_delete_oid(List *list, Oid datum)
Assert(IsOidList(list));
check_list_invariants(list);
- foreach(cell, list)
- {
- if (lfirst_oid(cell) == datum)
- return list_delete_cell(list, cell);
- }
+ cell = list_member_inline_internal_idx(list, datum);
+ if (cell != NULL)
+ return list_delete_cell(list, cell);
/* Didn't find a match: return the list unmodified */
return list;
@@ -1749,3 +1724,146 @@ list_oid_cmp(const ListCell *p1, const ListCell *p2)
return 1;
return 0;
}
+
+/*
+ * list_member_inline_helper
+ *
+ * Workhorse for list_member_inline_internal and
+ * list_member_inline_internal_idx.
+ */
+static inline bool
+list_member_inline_helper(const List *list, uint32 datum, uint32 *i)
+{
+#ifdef USE_NO_SIMD
+
+ *i = 0;
+
+#else
+
+ /*
+ * For better instruction-level parallelism, each loop iteration operates
+ * on a block of four registers.
+ */
+ const Vector32 keys = vector32_broadcast(datum); /* load copies of key */
+ const uint32 nelem_per_vector = sizeof(Vector32) / sizeof(uint32);
+ const uint32 nelem_per_iteration = 4 * nelem_per_vector;
+#ifdef USE_NEON
+ const Vector32 mask = (Vector32) vector64_broadcast(UINT64CONST(0xFFFFFFFF));
+#else
+ const Vector32 mask = vector64_broadcast(UINT64CONST(0xFFFFFFFF));
+#endif
+ const uint32 *elements = (const uint32 *) list->elements;
+
+ /* round down to multiple of elements per iteration */
+ const uint32 tail_idx = (list->length * 2) & ~(nelem_per_iteration - 1);
+
+ /*
+ * The SIMD optimized portion of this routine is written with the
+ * expectation that the 32-bit datum we are searching for only takes up
+ * half of a ListCell. If that changes, this routine must change, too.
+ */
+ Assert(sizeof(ListCell) == 8);
+
+ for (*i = 0; *i < tail_idx; *i += nelem_per_iteration)
+ {
+ Vector32 vals1,
+ vals2,
+ vals3,
+ vals4,
+ result1,
+ result2,
+ result3,
+ result4,
+ tmp1,
+ tmp2,
+ result,
+ masked;
+
+ /* load the next block into 4 registers */
+ vector32_load(&vals1, &elements[*i]);
+ vector32_load(&vals2, &elements[*i + nelem_per_vector]);
+ vector32_load(&vals3, &elements[*i + nelem_per_vector * 2]);
+ vector32_load(&vals4, &elements[*i + nelem_per_vector * 3]);
+
+ /* compare each value to the key */
+ result1 = vector32_eq(keys, vals1);
+ result2 = vector32_eq(keys, vals2);
+ result3 = vector32_eq(keys, vals3);
+ result4 = vector32_eq(keys, vals4);
+
+ /* combine the results into a single variable */
+ tmp1 = vector32_or(result1, result2);
+ tmp2 = vector32_or(result3, result4);
+ result = vector32_or(tmp1, tmp2);
+
+ /* filter out matches in space between data */
+ masked = vector32_and(result, mask);
+
+ /* break out and find the exact element if there was a match */
+ if (vector32_is_highbit_set(masked))
+ {
+ *i /= 2;
+ return true;
+ }
+ }
+
+#endif /* ! USE_NO_SIMD */
+
+ *i /= 2;
+ return false;
+}
+
+/*
+ * list_member_inline_internal
+ *
+ * Optimized linear search routine (using SIMD intrinsics where available) for
+ * lists with inline 32-bit data.
+ */
+static inline bool
+list_member_inline_internal(const List *list, uint32 datum)
+{
+ uint32 i = 0;
+ const ListCell *cell;
+
+ if (list == NIL)
+ return false;
+
+ if (list_member_inline_helper(list, datum, &i))
+ return true;
+
+ /* Process the remaining elements one at a time. */
+ for_each_from(cell, list, i)
+ {
+ if (lfirst_int(cell) == (int) datum)
+ return true;
+ }
+
+ return false;
+}
+
+/*
+ * list_member_inline_internal_idx
+ *
+ * Optimized linear search routine (using SIMD intrinsics where available) for
+ * lists with inline 32-bit data.
+ */
+static inline ListCell *
+list_member_inline_internal_idx(const List *list, uint32 datum)
+{
+ uint32 i = 0;
+ ListCell *cell;
+
+ if (list == NIL)
+ return NULL;
+
+ (void) list_member_inline_helper(list, datum, &i);
+
+ /* Process the remaining elements one at a time. */
+ for_each_from(cell, list, i)
+ {
+ if (lfirst_int(cell) == (int) datum)
+ return cell;
+ }
+
+ return NULL;
+}
--
2.25.1
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Subject: Re: optimize several list functions with SIMD intrinsics
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