Provide separate header file for built-in float types

Some data types under adt/ have separate header files, but most simple
ones do not, and their public functions are defined in builtins.h.  As
the patches improving geometric types will require making additional
functions public, this seems like a good opportunity to create a header
for floats types.

Commit 1acf757 made _cmp functions public to solve NaN issues locally
for GiST indexes.  This patch reworks it in favour of a more widely
applicable API.  The API uses inline functions, as they are easier to
use compared to macros, and avoid double-evaluation hazards.

Author: Emre Hasegeli
Reviewed-by: Kyotaro Horiguchi

Discussion: https://www.postgresql.org/message-id/CAE2gYzxF7-5djV6-cEvqQu-fNsnt%3DEqbOURx7ZDg%2BVv6ZMTWbg%40mail.gmail.com

Author: tvondra

contrib/btree_gin/btree_gin.c

@@ -10,6 +10,7 @@
 #include "utils/bytea.h"
 #include "utils/cash.h"
 #include "utils/date.h"
+#include "utils/float.h"
 #include "utils/inet.h"
 #include "utils/numeric.h"
 #include "utils/timestamp.h"

contrib/btree_gist/btree_ts.c

@@ -9,6 +9,7 @@
 #include "btree_utils_num.h"
 #include "utils/builtins.h"
 #include "utils/datetime.h"
+#include "utils/float.h"
 
 typedef struct
 {

contrib/cube/cube.c

@@ -13,7 +13,7 @@
 #include "access/gist.h"
 #include "access/stratnum.h"
 #include "utils/array.h"
-#include "utils/builtins.h"
+#include "utils/float.h"
 
 #include "cubedata.h"
 

contrib/cube/cubeparse.y

@@ -7,7 +7,7 @@
 #include "postgres.h"
 
 #include "cubedata.h"
-#include "utils/builtins.h"
+#include "utils/float.h"
 
 /* All grammar constructs return strings */
 #define YYSTYPE char *

contrib/postgres_fdw/postgres_fdw.c

@@ -35,6 +35,7 @@
 #include "optimizer/tlist.h"
 #include "parser/parsetree.h"
 #include "utils/builtins.h"
+#include "utils/float.h"
 #include "utils/guc.h"
 #include "utils/lsyscache.h"
 #include "utils/memutils.h"

src/backend/access/gist/gistget.c

@@ -22,7 +22,7 @@
 #include "storage/predicate.h"
 #include "pgstat.h"
 #include "lib/pairingheap.h"
-#include "utils/builtins.h"
+#include "utils/float.h"
 #include "utils/memutils.h"
 #include "utils/rel.h"
 

src/backend/access/gist/gistproc.c

@@ -22,6 +22,7 @@
 #include "access/gist.h"
 #include "access/stratnum.h"
 #include "utils/builtins.h"
+#include "utils/float.h"
 #include "utils/geo_decls.h"
 
 
@@ -33,15 +34,6 @@ static bool rtree_internal_consistent(BOX *key, BOX *query,
 /* Minimum accepted ratio of split */
 #define LIMIT_RATIO 0.3
 
-/* Convenience macros for NaN-aware comparisons */
-#define FLOAT8_EQ(a,b)	(float8_cmp_internal(a, b) == 0)
-#define FLOAT8_LT(a,b)	(float8_cmp_internal(a, b) < 0)
-#define FLOAT8_LE(a,b)	(float8_cmp_internal(a, b) <= 0)
-#define FLOAT8_GT(a,b)	(float8_cmp_internal(a, b) > 0)
-#define FLOAT8_GE(a,b)	(float8_cmp_internal(a, b) >= 0)
-#define FLOAT8_MAX(a,b)  (FLOAT8_GT(a, b) ? (a) : (b))
-#define FLOAT8_MIN(a,b)  (FLOAT8_LT(a, b) ? (a) : (b))
-
 
 /**************************************************
  * Box ops
@@ -53,10 +45,10 @@ static bool rtree_internal_consistent(BOX *key, BOX *query,
 static void
 rt_box_union(BOX *n, const BOX *a, const BOX *b)
 {
-	n->high.x = FLOAT8_MAX(a->high.x, b->high.x);
-	n->high.y = FLOAT8_MAX(a->high.y, b->high.y);
-	n->low.x = FLOAT8_MIN(a->low.x, b->low.x);
-	n->low.y = FLOAT8_MIN(a->low.y, b->low.y);
+	n->high.x = float8_max(a->high.x, b->high.x);
+	n->high.y = float8_max(a->high.y, b->high.y);
+	n->low.x = float8_min(a->low.x, b->low.x);
+	n->low.y = float8_min(a->low.y, b->low.y);
 }
 
 /*
@@ -73,8 +65,8 @@ size_box(const BOX *box)
 	 *
 	 * The less-than cases should not happen, but if they do, say "zero".
 	 */
-	if (FLOAT8_LE(box->high.x, box->low.x) ||
-		FLOAT8_LE(box->high.y, box->low.y))
+	if (float8_le(box->high.x, box->low.x) ||
+		float8_le(box->high.y, box->low.y))
 		return 0.0;
 
 	/*
@@ -143,13 +135,13 @@ gist_box_consistent(PG_FUNCTION_ARGS)
 static void
 adjustBox(BOX *b, const BOX *addon)
 {
-	if (FLOAT8_LT(b->high.x, addon->high.x))
+	if (float8_lt(b->high.x, addon->high.x))
 		b->high.x = addon->high.x;
-	if (FLOAT8_GT(b->low.x, addon->low.x))
+	if (float8_gt(b->low.x, addon->low.x))
 		b->low.x = addon->low.x;
-	if (FLOAT8_LT(b->high.y, addon->high.y))
+	if (float8_lt(b->high.y, addon->high.y))
 		b->high.y = addon->high.y;
-	if (FLOAT8_GT(b->low.y, addon->low.y))
+	if (float8_gt(b->low.y, addon->low.y))
 		b->low.y = addon->low.y;
 }
 
@@ -615,9 +607,9 @@ gist_box_picksplit(PG_FUNCTION_ARGS)
 			 * Find next lower bound of right group.
 			 */
 			while (i1 < nentries &&
-				   FLOAT8_EQ(rightLower, intervalsLower[i1].lower))
+				   float8_eq(rightLower, intervalsLower[i1].lower))
 			{
-				if (FLOAT8_LT(leftUpper, intervalsLower[i1].upper))
+				if (float8_lt(leftUpper, intervalsLower[i1].upper))
 					leftUpper = intervalsLower[i1].upper;
 				i1++;
 			}
@@ -630,7 +622,7 @@ gist_box_picksplit(PG_FUNCTION_ARGS)
 			 * left group.
 			 */
 			while (i2 < nentries &&
-				   FLOAT8_LE(intervalsUpper[i2].upper, leftUpper))
+				   float8_le(intervalsUpper[i2].upper, leftUpper))
 				i2++;
 
 			/*
@@ -652,9 +644,9 @@ gist_box_picksplit(PG_FUNCTION_ARGS)
 			/*
 			 * Find next upper bound of left group.
 			 */
-			while (i2 >= 0 && FLOAT8_EQ(leftUpper, intervalsUpper[i2].upper))
+			while (i2 >= 0 && float8_eq(leftUpper, intervalsUpper[i2].upper))
 			{
-				if (FLOAT8_GT(rightLower, intervalsUpper[i2].lower))
+				if (float8_gt(rightLower, intervalsUpper[i2].lower))
 					rightLower = intervalsUpper[i2].lower;
 				i2--;
 			}
@@ -666,7 +658,7 @@ gist_box_picksplit(PG_FUNCTION_ARGS)
 			 * Find count of intervals which anyway should be placed to the
 			 * right group.
 			 */
-			while (i1 >= 0 && FLOAT8_GE(intervalsLower[i1].lower, rightLower))
+			while (i1 >= 0 && float8_ge(intervalsLower[i1].lower, rightLower))
 				i1--;
 
 			/*
@@ -754,10 +746,10 @@ gist_box_picksplit(PG_FUNCTION_ARGS)
 			upper = box->high.y;
 		}
 
-		if (FLOAT8_LE(upper, context.leftUpper))
+		if (float8_le(upper, context.leftUpper))
 		{
 			/* Fits to the left group */
-			if (FLOAT8_GE(lower, context.rightLower))
+			if (float8_ge(lower, context.rightLower))
 			{
 				/* Fits also to the right group, so "common entry" */
 				commonEntries[commonEntriesCount++].index = i;
@@ -775,7 +767,7 @@ gist_box_picksplit(PG_FUNCTION_ARGS)
 			 * entry didn't fit on the left group, it better fit in the right
 			 * group.
 			 */
-			Assert(FLOAT8_GE(lower, context.rightLower));
+			Assert(float8_ge(lower, context.rightLower));
 
 			/* Doesn't fit to the left group, so join to the right group */
 			PLACE_RIGHT(box, i);
@@ -859,10 +851,10 @@ gist_box_same(PG_FUNCTION_ARGS)
 	bool	   *result = (bool *) PG_GETARG_POINTER(2);
 
 	if (b1 && b2)
-		*result = (FLOAT8_EQ(b1->low.x, b2->low.x) &&
-				   FLOAT8_EQ(b1->low.y, b2->low.y) &&
-				   FLOAT8_EQ(b1->high.x, b2->high.x) &&
-				   FLOAT8_EQ(b1->high.y, b2->high.y));
+		*result = (float8_eq(b1->low.x, b2->low.x) &&
+				   float8_eq(b1->low.y, b2->low.y) &&
+				   float8_eq(b1->high.x, b2->high.x) &&
+				   float8_eq(b1->high.y, b2->high.y));
 	else
 		*result = (b1 == NULL && b2 == NULL);
 	PG_RETURN_POINTER(result);

src/backend/access/gist/gistutil.c

@@ -21,7 +21,7 @@
 #include "catalog/pg_opclass.h"
 #include "storage/indexfsm.h"
 #include "storage/lmgr.h"
-#include "utils/builtins.h"
+#include "utils/float.h"
 #include "utils/syscache.h"