Use new overflow-safe integer comparison functions.

Commit 6b80394781 introduced integer comparison functions designed
to be as efficient as possible while avoiding overflow.  This
commit makes use of these functions in many of the in-tree qsort()
comparators to help ensure transitivity.  Many of these comparator
functions should also see a small performance boost.

Author: Mats Kindahl
Reviewed-by: Andres Freund, Fabrízio de Royes Mello
Discussion: https://postgr.es/m/CA%2B14426g2Wa9QuUpmakwPxXFWG_1FaY0AsApkvcTBy-YfS6uaw%40mail.gmail.com

5 files changed, 11 insertions, 23 deletions

diff --git a/src/backend/access/nbtree/nbtinsert.c b/src/backend/access/nbtree/nbtinsert.c
index 709edd1c179..e9cfc136042 100644
--- a/src/backend/access/nbtree/nbtinsert.c
+++ b/src/backend/access/nbtree/nbtinsert.c
@@ -19,6 +19,7 @@
 #include "access/nbtxlog.h"
 #include "access/transam.h"
 #include "access/xloginsert.h"
+#include "common/int.h"
 #include "common/pg_prng.h"
 #include "lib/qunique.h"
 #include "miscadmin.h"
@@ -3013,10 +3014,5 @@ _bt_blk_cmp(const void *arg1, const void *arg2)
 	BlockNumber b1 = *((BlockNumber *) arg1);
 	BlockNumber b2 = *((BlockNumber *) arg2);
 
-	if (b1 < b2)
-		return -1;
-	else if (b1 > b2)
-		return 1;
-
-	return 0;
+	return pg_cmp_u32(b1, b2);
 }
diff --git a/src/backend/access/nbtree/nbtpage.c b/src/backend/access/nbtree/nbtpage.c
index 567bade9f45..90990ea77a1 100644
--- a/src/backend/access/nbtree/nbtpage.c
+++ b/src/backend/access/nbtree/nbtpage.c
@@ -28,6 +28,7 @@
 #include "access/transam.h"
 #include "access/xlog.h"
 #include "access/xloginsert.h"
+#include "common/int.h"
 #include "miscadmin.h"
 #include "storage/indexfsm.h"
 #include "storage/lmgr.h"
@@ -1466,14 +1467,9 @@ _bt_delitems_cmp(const void *a, const void *b)
 	TM_IndexDelete *indexdelete1 = (TM_IndexDelete *) a;
 	TM_IndexDelete *indexdelete2 = (TM_IndexDelete *) b;
 
-	if (indexdelete1->id > indexdelete2->id)
-		return 1;
-	if (indexdelete1->id < indexdelete2->id)
-		return -1;
+	Assert(indexdelete1->id != indexdelete2->id);
 
-	Assert(false);
-
-	return 0;
+	return pg_cmp_s16(indexdelete1->id, indexdelete2->id);
 }
 
 /*
diff --git a/src/backend/access/nbtree/nbtsplitloc.c b/src/backend/access/nbtree/nbtsplitloc.c
index d0b1d825787..490e7bfd4df 100644
--- a/src/backend/access/nbtree/nbtsplitloc.c
+++ b/src/backend/access/nbtree/nbtsplitloc.c
@@ -15,6 +15,7 @@
 #include "postgres.h"
 
 #include "access/nbtree.h"
+#include "common/int.h"
 #include "storage/lmgr.h"
 
 typedef enum
@@ -596,12 +597,7 @@ _bt_splitcmp(const void *arg1, const void *arg2)
 	SplitPoint *split1 = (SplitPoint *) arg1;
 	SplitPoint *split2 = (SplitPoint *) arg2;
 
-	if (split1->curdelta > split2->curdelta)
-		return 1;
-	if (split1->curdelta < split2->curdelta)
-		return -1;
-
-	return 0;
+	return pg_cmp_s16(split1->curdelta, split2->curdelta);
 }
 
 /*
diff --git a/src/backend/access/spgist/spgdoinsert.c b/src/backend/access/spgist/spgdoinsert.c
index bb063c858d9..a4995c168b4 100644
--- a/src/backend/access/spgist/spgdoinsert.c
+++ b/src/backend/access/spgist/spgdoinsert.c
@@ -19,6 +19,7 @@
 #include "access/spgist_private.h"
 #include "access/spgxlog.h"
 #include "access/xloginsert.h"
+#include "common/int.h"
 #include "common/pg_prng.h"
 #include "miscadmin.h"
 #include "storage/bufmgr.h"
@@ -110,9 +111,7 @@ addNode(SpGistState *state, SpGistInnerTuple tuple, Datum label, int offset)
 static int
 cmpOffsetNumbers(const void *a, const void *b)
 {
-	if (*(const OffsetNumber *) a == *(const OffsetNumber *) b)
-		return 0;
-	return (*(const OffsetNumber *) a > *(const OffsetNumber *) b) ? 1 : -1;
+	return pg_cmp_u16(*(const OffsetNumber *) a, *(const OffsetNumber *) b);
 }
 
 /*
diff --git a/src/backend/access/spgist/spgtextproc.c b/src/backend/access/spgist/spgtextproc.c
index b8fd0c2ad85..d5db5225a9c 100644
--- a/src/backend/access/spgist/spgtextproc.c
+++ b/src/backend/access/spgist/spgtextproc.c
@@ -40,6 +40,7 @@
 #include "postgres.h"
 
 #include "access/spgist.h"
+#include "common/int.h"
 #include "catalog/pg_type.h"
 #include "mb/pg_wchar.h"
 #include "utils/builtins.h"
@@ -325,7 +326,7 @@ cmpNodePtr(const void *a, const void *b)
 	const spgNodePtr *aa = (const spgNodePtr *) a;
 	const spgNodePtr *bb = (const spgNodePtr *) b;
 
-	return aa->c - bb->c;
+	return pg_cmp_s16(aa->c, bb->c);
 }
 
 Datum