Simplify checks for deterministic collations.

Remove redundant checks for locale->collate_is_c now that we always
have a valid pg_locale_t.

Also, remove pg_locale_deterministic() wrapper, which is no longer
useful after commit e9931bfb75. Just check the field directly,
consistent with other fields in pg_locale_t.

Author: Andreas Karlsson
Discussion: https://postgr.es/m/60929555-4709-40a7-b136-bcb44cff5a3c@proxel.se

src/backend/access/hash/hashfunc.c

@@ -279,7 +279,7 @@ hashtext(PG_FUNCTION_ARGS)
 
 	mylocale = pg_newlocale_from_collation(collid);
 
-	if (pg_locale_deterministic(mylocale))
+	if (mylocale->deterministic)
 	{
 		result = hash_any((unsigned char *) VARDATA_ANY(key),
 						  VARSIZE_ANY_EXHDR(key));
@@ -334,7 +334,7 @@ hashtextextended(PG_FUNCTION_ARGS)
 
 	mylocale = pg_newlocale_from_collation(collid);
 
-	if (pg_locale_deterministic(mylocale))
+	if (mylocale->deterministic)
 	{
 		result = hash_any_extended((unsigned char *) VARDATA_ANY(key),
 								   VARSIZE_ANY_EXHDR(key),

src/backend/regex/regc_pg_locale.c

@@ -260,7 +260,7 @@ pg_set_regex_collation(Oid collation)
 	{
 		locale = pg_newlocale_from_collation(collation);
 
-		if (!pg_locale_deterministic(locale))
+		if (!locale->deterministic)
 			ereport(ERROR,
 					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 					 errmsg("nondeterministic collations are not supported for regular expressions")));

src/backend/utils/adt/like.c

@@ -151,7 +151,7 @@ GenericMatchText(const char *s, int slen, const char *p, int plen, Oid collation
 	{
 		pg_locale_t locale = pg_newlocale_from_collation(collation);
 
-		if (!pg_locale_deterministic(locale))
+		if (!locale->deterministic)
 			ereport(ERROR,
 					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 					 errmsg("nondeterministic collations are not supported for LIKE")));
@@ -188,7 +188,7 @@ Generic_Text_IC_like(text *str, text *pat, Oid collation)
 
 	locale = pg_newlocale_from_collation(collation);
 
-	if (!pg_locale_deterministic(locale))
+	if (!locale->deterministic)
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("nondeterministic collations are not supported for ILIKE")));

src/backend/utils/adt/pg_locale.c

@@ -1415,13 +1415,6 @@ make_icu_collator(const char *iculocstr,
 #endif							/* not USE_ICU */
 }
 
-
-bool
-pg_locale_deterministic(pg_locale_t locale)
-{
-	return locale->deterministic;
-}
-
 /*
  * Initialize default_locale with database locale settings.
  */

src/backend/utils/adt/varchar.c

@@ -757,7 +757,7 @@ bpchareq(PG_FUNCTION_ARGS)
 
 	mylocale = pg_newlocale_from_collation(collid);
 
-	if (mylocale->collate_is_c || pg_locale_deterministic(mylocale))
+	if (mylocale->deterministic)
 	{
 		/*
 		 * Since we only care about equality or not-equality, we can avoid all
@@ -798,7 +798,7 @@ bpcharne(PG_FUNCTION_ARGS)
 
 	mylocale = pg_newlocale_from_collation(collid);
 
-	if (mylocale->collate_is_c || pg_locale_deterministic(mylocale))
+	if (mylocale->deterministic)
 	{
 		/*
 		 * Since we only care about equality or not-equality, we can avoid all
@@ -1005,7 +1005,7 @@ hashbpchar(PG_FUNCTION_ARGS)
 
 	mylocale = pg_newlocale_from_collation(collid);
 
-	if (pg_locale_deterministic(mylocale))
+	if (mylocale->deterministic)
 	{
 		result = hash_any((unsigned char *) keydata, keylen);
 	}
@@ -1061,7 +1061,7 @@ hashbpcharextended(PG_FUNCTION_ARGS)
 
 	mylocale = pg_newlocale_from_collation(collid);
 
-	if (pg_locale_deterministic(mylocale))
+	if (mylocale->deterministic)
 	{
 		result = hash_any_extended((unsigned char *) keydata, keylen,
 								   PG_GETARG_INT64(1));

src/backend/utils/adt/varlena.c

@@ -1223,7 +1223,7 @@ text_position_setup(text *t1, text *t2, Oid collid, TextPositionState *state)
 
 	mylocale = pg_newlocale_from_collation(collid);
 
-	if (!pg_locale_deterministic(mylocale))
+	if (!mylocale->deterministic)
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("nondeterministic collations are not supported for substring searches")));
@@ -1567,7 +1567,7 @@ varstr_cmp(const char *arg1, int len1, const char *arg2, int len2, Oid collid)
 		result = pg_strncoll(arg1, len1, arg2, len2, mylocale);
 
 		/* Break tie if necessary. */
-		if (result == 0 && pg_locale_deterministic(mylocale))
+		if (result == 0 && mylocale->deterministic)
 		{
 			result = memcmp(arg1, arg2, Min(len1, len2));
 			if ((result == 0) && (len1 != len2))
@@ -1618,7 +1618,7 @@ texteq(PG_FUNCTION_ARGS)
 
 	mylocale = pg_newlocale_from_collation(collid);
 
-	if (pg_locale_deterministic(mylocale))
+	if (mylocale->deterministic)
 	{
 		Datum		arg1 = PG_GETARG_DATUM(0);
 		Datum		arg2 = PG_GETARG_DATUM(1);
@@ -1673,7 +1673,7 @@ textne(PG_FUNCTION_ARGS)
 
 	mylocale = pg_newlocale_from_collation(collid);
 
-	if (pg_locale_deterministic(mylocale))
+	if (mylocale->deterministic)
 	{
 		Datum		arg1 = PG_GETARG_DATUM(0);
 		Datum		arg2 = PG_GETARG_DATUM(1);
@@ -1786,7 +1786,7 @@ text_starts_with(PG_FUNCTION_ARGS)
 
 	mylocale = pg_newlocale_from_collation(collid);
 
-	if (!pg_locale_deterministic(mylocale))
+	if (!mylocale->deterministic)
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("nondeterministic collations are not supported for substring searches")));
@@ -2200,7 +2200,7 @@ varstrfastcmp_locale(char *a1p, int len1, char *a2p, int len2, SortSupport ssup)
 	result = pg_strcoll(sss->buf1, sss->buf2, sss->locale);
 
 	/* Break tie if necessary. */
-	if (result == 0 && pg_locale_deterministic(sss->locale))
+	if (result == 0 && sss->locale->deterministic)
 		result = strcmp(sss->buf1, sss->buf2);
 
 	/* Cache result, perhaps saving an expensive strcoll() call next time */
@@ -2539,11 +2539,7 @@ btvarstrequalimage(PG_FUNCTION_ARGS)
 
 	locale = pg_newlocale_from_collation(collid);
 
-	if (locale->collate_is_c ||
-		pg_locale_deterministic(locale))
-		PG_RETURN_BOOL(true);
-	else
-		PG_RETURN_BOOL(false);
+	PG_RETURN_BOOL(locale->deterministic);
 }
 
 Datum

src/include/utils/pg_locale.h

@@ -108,7 +108,6 @@ extern void make_icu_collator(const char *iculocstr,
 							  const char *icurules,
 							  struct pg_locale_struct *resultp);
 
-extern bool pg_locale_deterministic(pg_locale_t locale);
 extern void init_database_collation(void);
 extern pg_locale_t pg_newlocale_from_collation(Oid collid);