branches/zip: Minor cleanup of B-tree cursor operations.

btr_pcur_get_rel_pos(): Add a const qualifier.

btr_pcur_get_btr_cur(), btr_pcur_get_page_cur(): btr_cur_get_page_cur():
Define as const-preserving macros.

btr_pcur_is_on_user_rec(), btr_pcur_is_after_last_on_page(),
btr_pcur_is_before_first_on_page(): Remove the unused parameter mtr.
Add a const qualifier.

btr_pcur_move_to_next_on_page(), btr_pcur_move_to_prev_on_page():
Remove the unused parameter mtr.

page_cur_search(): Add const qualifiers.

page_cur_get_page(), page_cur_is_before_first(), page_cur_is_after_last():
Add debug assertions.

btr/btr0pcur.c

@@ -303,7 +303,7 @@ btr_pcur_restore_position(
 	cursor->search_mode = old_mode;
 
 	if (cursor->rel_pos == BTR_PCUR_ON
-	    && btr_pcur_is_on_user_rec(cursor, mtr)
+	    && btr_pcur_is_on_user_rec(cursor)
 	    && 0 == cmp_dtuple_rec(tuple, btr_pcur_get_rec(cursor),
 				   rec_get_offsets(
 					   btr_pcur_get_rec(cursor), index,
@@ -383,7 +383,7 @@ btr_pcur_move_to_next_page(
 
 	ut_a(cursor->pos_state == BTR_PCUR_IS_POSITIONED);
 	ut_ad(cursor->latch_mode != BTR_NO_LATCHES);
-	ut_ad(btr_pcur_is_after_last_on_page(cursor, mtr));
+	ut_ad(btr_pcur_is_after_last_on_page(cursor));
 
 	cursor->old_stored = BTR_PCUR_OLD_NOT_STORED;
 
@@ -438,7 +438,7 @@ btr_pcur_move_backward_from_page(
 
 	ut_a(cursor->pos_state == BTR_PCUR_IS_POSITIONED);
 	ut_ad(cursor->latch_mode != BTR_NO_LATCHES);
-	ut_ad(btr_pcur_is_before_first_on_page(cursor, mtr));
+	ut_ad(btr_pcur_is_before_first_on_page(cursor));
 	ut_ad(!btr_pcur_is_before_first_in_tree(cursor, mtr));
 
 	latch_mode = cursor->latch_mode;
@@ -469,7 +469,7 @@ btr_pcur_move_backward_from_page(
 	space = buf_block_get_space(btr_pcur_get_block(cursor));
 
 	if (prev_page_no == FIL_NULL) {
-	} else if (btr_pcur_is_before_first_on_page(cursor, mtr)) {
+	} else if (btr_pcur_is_before_first_on_page(cursor)) {
 
 		prev_block = btr_pcur_get_btr_cur(cursor)->left_block;
 
@@ -512,7 +512,7 @@ btr_pcur_move_to_prev(
 
 	cursor->old_stored = BTR_PCUR_OLD_NOT_STORED;
 
-	if (btr_pcur_is_before_first_on_page(cursor, mtr)) {
+	if (btr_pcur_is_before_first_on_page(cursor)) {
 
 		if (btr_pcur_is_before_first_in_tree(cursor, mtr)) {
 
@@ -524,7 +524,7 @@ btr_pcur_move_to_prev(
 		return(TRUE);
 	}
 
-	btr_pcur_move_to_prev_on_page(cursor, mtr);
+	btr_pcur_move_to_prev_on_page(cursor);
 
 	return(TRUE);
 }
@@ -553,7 +553,7 @@ btr_pcur_open_on_user_rec(
 
 	if ((mode == PAGE_CUR_GE) || (mode == PAGE_CUR_G)) {
 
-		if (btr_pcur_is_after_last_on_page(cursor, mtr)) {
+		if (btr_pcur_is_after_last_on_page(cursor)) {
 
 			btr_pcur_move_to_next_user_rec(cursor, mtr);
 		}

dict/dict0load.c

@@ -88,7 +88,7 @@ dict_get_first_table_name_in_db(
 loop:
 	rec = btr_pcur_get_rec(&pcur);
 
-	if (!btr_pcur_is_on_user_rec(&pcur, &mtr)) {
+	if (!btr_pcur_is_on_user_rec(&pcur)) {
 		/* Not found */
 
 		btr_pcur_close(&pcur);
@@ -167,7 +167,7 @@ loop:
 
 	rec = btr_pcur_get_rec(&pcur);
 
-	if (!btr_pcur_is_on_user_rec(&pcur, &mtr)) {
+	if (!btr_pcur_is_on_user_rec(&pcur)) {
 		/* end of index */
 
 		btr_pcur_close(&pcur);
@@ -297,7 +297,7 @@ loop:
 
 	rec = btr_pcur_get_rec(&pcur);
 
-	if (!btr_pcur_is_on_user_rec(&pcur, &mtr)) {
+	if (!btr_pcur_is_on_user_rec(&pcur)) {
 		/* end of index */
 
 		btr_pcur_close(&pcur);
@@ -418,7 +418,7 @@ dict_load_columns(
 
 		rec = btr_pcur_get_rec(&pcur);
 
-		ut_a(btr_pcur_is_on_user_rec(&pcur, &mtr));
+		ut_a(btr_pcur_is_on_user_rec(&pcur));
 
 		ut_a(!rec_get_deleted_flag(rec, 0));
 
@@ -522,7 +522,7 @@ dict_load_fields(
 
 		rec = btr_pcur_get_rec(&pcur);
 
-		ut_a(btr_pcur_is_on_user_rec(&pcur, &mtr));
+		ut_a(btr_pcur_is_on_user_rec(&pcur));
 
 		/* There could be delete marked records in SYS_FIELDS
 		because SYS_FIELDS.INDEX_ID can be updated
@@ -636,7 +636,7 @@ dict_load_indexes(
 	btr_pcur_open_on_user_rec(sys_index, tuple, PAGE_CUR_GE,
 				  BTR_SEARCH_LEAF, &pcur, &mtr);
 	for (;;) {
-		if (!btr_pcur_is_on_user_rec(&pcur, &mtr)) {
+		if (!btr_pcur_is_on_user_rec(&pcur)) {
 
 			break;
 		}
@@ -791,7 +791,7 @@ dict_load_table(
 				  BTR_SEARCH_LEAF, &pcur, &mtr);
 	rec = btr_pcur_get_rec(&pcur);
 
-	if (!btr_pcur_is_on_user_rec(&pcur, &mtr)
+	if (!btr_pcur_is_on_user_rec(&pcur)
 	    || rec_get_deleted_flag(rec, 0)) {
 		/* Not found */
 err_exit:
@@ -973,7 +973,7 @@ dict_load_table_on_id(
 				  BTR_SEARCH_LEAF, &pcur, &mtr);
 	rec = btr_pcur_get_rec(&pcur);
 
-	if (!btr_pcur_is_on_user_rec(&pcur, &mtr)
+	if (!btr_pcur_is_on_user_rec(&pcur)
 	    || rec_get_deleted_flag(rec, 0)) {
 		/* Not found */
 
@@ -1082,7 +1082,7 @@ dict_load_foreign_cols(
 
 		rec = btr_pcur_get_rec(&pcur);
 
-		ut_a(btr_pcur_is_on_user_rec(&pcur, &mtr));
+		ut_a(btr_pcur_is_on_user_rec(&pcur));
 		ut_a(!rec_get_deleted_flag(rec, 0));
 
 		field = rec_get_nth_field_old(rec, 0, &len);
@@ -1153,7 +1153,7 @@ dict_load_foreign(
 				  BTR_SEARCH_LEAF, &pcur, &mtr);
 	rec = btr_pcur_get_rec(&pcur);
 
-	if (!btr_pcur_is_on_user_rec(&pcur, &mtr)
+	if (!btr_pcur_is_on_user_rec(&pcur)
 	    || rec_get_deleted_flag(rec, 0)) {
 		/* Not found */
 
@@ -1297,7 +1297,7 @@ start_load:
 loop:
 	rec = btr_pcur_get_rec(&pcur);
 
-	if (!btr_pcur_is_on_user_rec(&pcur, &mtr)) {
+	if (!btr_pcur_is_on_user_rec(&pcur)) {
 		/* End of index */
 
 		goto load_next_index;

ibuf/ibuf0ibuf.c

@@ -2558,7 +2558,7 @@ ibuf_update_max_tablespace_id(void)
 				    &pcur, TRUE, &mtr);
 	btr_pcur_move_to_prev(&pcur, &mtr);
 
-	if (btr_pcur_is_before_first_on_page(&pcur, &mtr)) {
+	if (btr_pcur_is_before_first_on_page(&pcur)) {
 		/* The tree is empty */
 
 		max_space_id = 0;
@@ -3333,14 +3333,14 @@ loop:
 	index page */
 	btr_pcur_open_on_user_rec(ibuf_data->index, search_tuple, PAGE_CUR_GE,
 				  BTR_MODIFY_LEAF, &pcur, &mtr);
-	if (!btr_pcur_is_on_user_rec(&pcur, &mtr)) {
+	if (!btr_pcur_is_on_user_rec(&pcur)) {
 		ut_ad(btr_pcur_is_after_last_in_tree(&pcur, &mtr));
 
 		goto reset_bit;
 	}
 
 	for (;;) {
-		ut_ad(btr_pcur_is_on_user_rec(&pcur, &mtr));
+		ut_ad(btr_pcur_is_on_user_rec(&pcur));
 
 		ibuf_rec = btr_pcur_get_rec(&pcur);
 
@@ -3393,7 +3393,7 @@ loop:
 			goto loop;
 		}
 
-		if (btr_pcur_is_after_last_on_page(&pcur, &mtr)) {
+		if (btr_pcur_is_after_last_on_page(&pcur)) {
 			mtr_commit(&mtr);
 			btr_pcur_close(&pcur);
 
@@ -3505,14 +3505,14 @@ loop:
 	space */
 	btr_pcur_open_on_user_rec(ibuf_data->index, search_tuple, PAGE_CUR_GE,
 				  BTR_MODIFY_LEAF, &pcur, &mtr);
-	if (!btr_pcur_is_on_user_rec(&pcur, &mtr)) {
+	if (!btr_pcur_is_on_user_rec(&pcur)) {
 		ut_ad(btr_pcur_is_after_last_in_tree(&pcur, &mtr));
 
 		goto leave_loop;
 	}
 
 	for (;;) {
-		ut_ad(btr_pcur_is_on_user_rec(&pcur, &mtr));
+		ut_ad(btr_pcur_is_on_user_rec(&pcur));
 
 		ibuf_rec = btr_pcur_get_rec(&pcur);
 
@@ -3538,7 +3538,7 @@ loop:
 			goto loop;
 		}
 
-		if (btr_pcur_is_after_last_on_page(&pcur, &mtr)) {
+		if (btr_pcur_is_after_last_on_page(&pcur)) {
 			mtr_commit(&mtr);
 			btr_pcur_close(&pcur);
 

include/btr0cur.h

@@ -27,14 +27,19 @@ Created 10/16/1994 Heikki Tuuri
 #define BTR_CUR_ADAPT
 #define BTR_CUR_HASH_ADAPT
 
+#ifdef UNIV_DEBUG
 /*************************************************************
 Returns the page cursor component of a tree cursor. */
 UNIV_INLINE
 page_cur_t*
 btr_cur_get_page_cur(
 /*=================*/
-				/* out: pointer to page cursor component */
+					/* out: pointer to page cursor
-	btr_cur_t*	cursor);/* in: tree cursor */
+					component */
+	const btr_cur_t*	cursor);/* in: tree cursor */
+#else /* UNIV_DEBUG */
+# define btr_cur_get_page_cur(cursor) (&(cursor)->page_cur)
+#endif /* UNIV_DEBUG */
 /*************************************************************
 Returns the buffer block on which the tree cursor is positioned. */
 UNIV_INLINE

include/btr0cur.ic

@@ -8,17 +8,20 @@ Created 10/16/1994 Heikki Tuuri
 
 #include "btr0btr.h"
 
+#ifdef UNIV_DEBUG
 /*************************************************************
 Returns the page cursor component of a tree cursor. */
 UNIV_INLINE
 page_cur_t*
 btr_cur_get_page_cur(
 /*=================*/
-				/* out: pointer to page cursor component */
+					/* out: pointer to page cursor
-	btr_cur_t*	cursor)	/* in: tree cursor */
+					component */
+	const btr_cur_t*	cursor)	/* in: tree cursor */
 {
-	return(&(cursor->page_cur));
+	return(&((btr_cur_t*) cursor)->page_cur);
 }
+#endif /* UNIV_DEBUG */
 /*************************************************************
 Returns the buffer block on which the tree cursor is positioned. */
 UNIV_INLINE

include/btr0pcur.h

@@ -228,8 +228,8 @@ UNIV_INLINE
 ulint
 btr_pcur_get_rel_pos(
 /*=================*/
-				/* out: BTR_PCUR_ON, ... */
+					/* out: BTR_PCUR_ON, ... */
-	btr_pcur_t*	cursor);/* in: persistent cursor */
+	const btr_pcur_t*	cursor);/* in: persistent cursor */
 /*************************************************************
 Sets the mtr field for a pcur. */
 UNIV_INLINE
@@ -346,22 +346,29 @@ btr_pcur_move_backward_from_page(
 	btr_pcur_t*	cursor,	/* in: persistent cursor, must be on the
 				first record of the current page */
 	mtr_t*		mtr);	/* in: mtr */
+#ifdef UNIV_DEBUG
 /*************************************************************
 Returns the btr cursor component of a persistent cursor. */
 UNIV_INLINE
 btr_cur_t*
 btr_pcur_get_btr_cur(
 /*=================*/
-				/* out: pointer to btr cursor component */
+						/* out: pointer to
-	btr_pcur_t*	cursor);	/* in: persistent cursor */
+						btr cursor component */
+	const btr_pcur_t*	cursor);	/* in: persistent cursor */
 /*************************************************************
 Returns the page cursor component of a persistent cursor. */
 UNIV_INLINE
 page_cur_t*
 btr_pcur_get_page_cur(
 /*==================*/
-				/* out: pointer to page cursor component */
+						/* out: pointer to
-	btr_pcur_t*	cursor);	/* in: persistent cursor */
+						page cursor component */
+	const btr_pcur_t*	cursor);	/* in: persistent cursor */
+#else /* UNIV_DEBUG */
+# define btr_pcur_get_btr_cur(cursor) (&(cursor)->btr_cur)
+# define btr_pcur_get_page_cur(cursor) (&(cursor)->btr_cur.page_cur)
+#endif /* UNIV_DEBUG */
 /*************************************************************
 Returns the page of a persistent cursor. */
 UNIV_INLINE
@@ -392,8 +399,7 @@ UNIV_INLINE
 ibool
 btr_pcur_is_on_user_rec(
 /*====================*/
-	btr_pcur_t*	cursor,	/* in: persistent cursor */
+	const btr_pcur_t*	cursor);/* in: persistent cursor */
-	mtr_t*		mtr);	/* in: mtr */
 /*************************************************************
 Checks if the persistent cursor is after the last user record on
 a page. */
@@ -401,8 +407,7 @@ UNIV_INLINE
 ibool
 btr_pcur_is_after_last_on_page(
 /*===========================*/
-	btr_pcur_t*	cursor,	/* in: persistent cursor */
+	const btr_pcur_t*	cursor);/* in: persistent cursor */
-	mtr_t*		mtr);	/* in: mtr */
 /*************************************************************
 Checks if the persistent cursor is before the first user record on
 a page. */
@@ -410,8 +415,7 @@ UNIV_INLINE
 ibool
 btr_pcur_is_before_first_on_page(
 /*=============================*/
-	btr_pcur_t*	cursor,	/* in: persistent cursor */
+	const btr_pcur_t*	cursor);/* in: persistent cursor */
-	mtr_t*		mtr);	/* in: mtr */
 /*************************************************************
 Checks if the persistent cursor is before the first user record in
 the index tree. */
@@ -436,16 +440,14 @@ UNIV_INLINE
 void
 btr_pcur_move_to_next_on_page(
 /*==========================*/
-	btr_pcur_t*	cursor,	/* in: persistent cursor */
+	btr_pcur_t*	cursor);/* in/out: persistent cursor */
-	mtr_t*		mtr);	/* in: mtr */
 /*************************************************************
 Moves the persistent cursor to the previous record on the same page. */
 UNIV_INLINE
 void
 btr_pcur_move_to_prev_on_page(
 /*==========================*/
-	btr_pcur_t*	cursor,	/* in: persistent cursor */
+	btr_pcur_t*	cursor);/* in/out: persistent cursor */
-	mtr_t*		mtr);	/* in: mtr */
 
 
 /* The persistent B-tree cursor structure. This is used mainly for SQL

include/btr0pcur.ic

@@ -13,8 +13,8 @@ UNIV_INLINE
 ulint
 btr_pcur_get_rel_pos(
 /*=================*/
-				/* out: BTR_PCUR_ON, ... */
+					/* out: BTR_PCUR_ON, ... */
-	btr_pcur_t*	cursor)	/* in: persistent cursor */
+	const btr_pcur_t*	cursor)	/* in: persistent cursor */
 {
 	ut_ad(cursor);
 	ut_ad(cursor->old_rec);
@@ -53,16 +53,19 @@ btr_pcur_get_mtr(
 	return(cursor->mtr);
 }
 
+#ifdef UNIV_DEBUG
 /*************************************************************
 Returns the btr cursor component of a persistent cursor. */
 UNIV_INLINE
 btr_cur_t*
 btr_pcur_get_btr_cur(
 /*=================*/
-				/* out: pointer to btr cursor component */
+					/* out: pointer to
-	btr_pcur_t*	cursor)	/* in: persistent cursor */
+					btr cursor component */
+	const btr_pcur_t*	cursor)	/* in: persistent cursor */
 {
-	return(&(cursor->btr_cur));
+	const btr_cur_t*	btr_cur = &cursor->btr_cur;
+	return((btr_cur_t*) btr_cur);
 }
 
 /*************************************************************
@@ -71,12 +74,13 @@ UNIV_INLINE
 page_cur_t*
 btr_pcur_get_page_cur(
 /*==================*/
-				/* out: pointer to page cursor component */
+					/* out: pointer to page cursor
-	btr_pcur_t*	cursor)	/* in: persistent cursor */
+					component */
+	const btr_pcur_t*	cursor)	/* in: persistent cursor */
 {
-	return(btr_cur_get_page_cur(&(cursor->btr_cur)));
+	return(btr_cur_get_page_cur(btr_pcur_get_btr_cur(cursor)));
 }
-
+#endif /* UNIV_DEBUG */
 /*************************************************************
 Returns the page of a persistent cursor. */
 UNIV_INLINE
@@ -172,10 +176,8 @@ UNIV_INLINE
 ibool
 btr_pcur_is_after_last_on_page(
 /*===========================*/
-	btr_pcur_t*	cursor,	/* in: persistent cursor */
+	const btr_pcur_t*	cursor)	/* in: persistent cursor */
-	mtr_t*		mtr)	/* in: mtr */
 {
-	UT_NOT_USED(mtr);
 	ut_ad(cursor->pos_state == BTR_PCUR_IS_POSITIONED);
 	ut_ad(cursor->latch_mode != BTR_NO_LATCHES);
 
@@ -189,10 +191,8 @@ UNIV_INLINE
 ibool
 btr_pcur_is_before_first_on_page(
 /*=============================*/
-	btr_pcur_t*	cursor,	/* in: persistent cursor */
+	const btr_pcur_t*	cursor)	/* in: persistent cursor */
-	mtr_t*		mtr)	/* in: mtr */
 {
-	UT_NOT_USED(mtr);
 	ut_ad(cursor->pos_state == BTR_PCUR_IS_POSITIONED);
 	ut_ad(cursor->latch_mode != BTR_NO_LATCHES);
 
@@ -205,14 +205,13 @@ UNIV_INLINE
 ibool
 btr_pcur_is_on_user_rec(
 /*====================*/
-	btr_pcur_t*	cursor,	/* in: persistent cursor */
+	const btr_pcur_t*	cursor)	/* in: persistent cursor */
-	mtr_t*		mtr)	/* in: mtr */
 {
 	ut_ad(cursor->pos_state == BTR_PCUR_IS_POSITIONED);
 	ut_ad(cursor->latch_mode != BTR_NO_LATCHES);
 
-	if ((btr_pcur_is_before_first_on_page(cursor, mtr))
+	if (btr_pcur_is_before_first_on_page(cursor)
-	    || (btr_pcur_is_after_last_on_page(cursor, mtr))) {
+	    || btr_pcur_is_after_last_on_page(cursor)) {
 
 		return(FALSE);
 	}
@@ -268,10 +267,8 @@ UNIV_INLINE
 void
 btr_pcur_move_to_next_on_page(
 /*==========================*/
-	btr_pcur_t*	cursor,	/* in: persistent cursor */
+	btr_pcur_t*	cursor)	/* in/out: persistent cursor */
-	mtr_t*		mtr)	/* in: mtr */
 {
-	UT_NOT_USED(mtr);
 	ut_ad(cursor->pos_state == BTR_PCUR_IS_POSITIONED);
 	ut_ad(cursor->latch_mode != BTR_NO_LATCHES);
 
@@ -286,10 +283,8 @@ UNIV_INLINE
 void
 btr_pcur_move_to_prev_on_page(
 /*==========================*/
-	btr_pcur_t*	cursor,	/* in: persistent cursor */
+	btr_pcur_t*	cursor)	/* in/out: persistent cursor */
-	mtr_t*		mtr)	/* in: mtr */
 {
-	UT_NOT_USED(mtr);
 	ut_ad(cursor->pos_state == BTR_PCUR_IS_POSITIONED);
 	ut_ad(cursor->latch_mode != BTR_NO_LATCHES);
 
@@ -333,7 +328,7 @@ btr_pcur_move_to_next_user_rec(
 	ut_ad(cursor->latch_mode != BTR_NO_LATCHES);
 	cursor->old_stored = BTR_PCUR_OLD_NOT_STORED;
 loop:
-	if (btr_pcur_is_after_last_on_page(cursor, mtr)) {
+	if (btr_pcur_is_after_last_on_page(cursor)) {
 
 		if (btr_pcur_is_after_last_in_tree(cursor, mtr)) {
 
@@ -342,10 +337,10 @@ loop:
 
 		btr_pcur_move_to_next_page(cursor, mtr);
 	} else {
-		btr_pcur_move_to_next_on_page(cursor, mtr);
+		btr_pcur_move_to_next_on_page(cursor);
 	}
 
-	if (btr_pcur_is_on_user_rec(cursor, mtr)) {
+	if (btr_pcur_is_on_user_rec(cursor)) {
 
 		return(TRUE);
 	}
@@ -371,7 +366,7 @@ btr_pcur_move_to_next(
 
 	cursor->old_stored = BTR_PCUR_OLD_NOT_STORED;
 
-	if (btr_pcur_is_after_last_on_page(cursor, mtr)) {
+	if (btr_pcur_is_after_last_on_page(cursor)) {
 
 		if (btr_pcur_is_after_last_in_tree(cursor, mtr)) {
 
@@ -383,7 +378,7 @@ btr_pcur_move_to_next(
 		return(TRUE);
 	}
 
-	btr_pcur_move_to_next_on_page(cursor, mtr);
+	btr_pcur_move_to_next_on_page(cursor);
 
 	return(TRUE);
 }

include/page0cur.h

@@ -238,13 +238,15 @@ UNIV_INLINE
 ulint
 page_cur_search(
 /*============*/
-				/* out: number of matched fields on the left */
+					/* out: number of matched
-	buf_block_t*	block,	/* in: buffer block */
+					fields on the left */
-	dict_index_t*	index,	/* in: record descriptor */
+	const buf_block_t*	block,	/* in: buffer block */
-	const dtuple_t*	tuple,	/* in: data tuple */
+	const dict_index_t*	index,	/* in: record descriptor */
-	ulint		mode,	/* in: PAGE_CUR_L, PAGE_CUR_LE, PAGE_CUR_G,
+	const dtuple_t*		tuple,	/* in: data tuple */
-				or PAGE_CUR_GE */
+	ulint			mode,	/* in: PAGE_CUR_L,
-	page_cur_t*	cursor);/* out: page cursor */
+					PAGE_CUR_LE, PAGE_CUR_G, or
+					PAGE_CUR_GE */
+	page_cur_t*		cursor);/* out: page cursor */
 /********************************************************************
 Searches the right position for a page cursor. */
 

include/page0cur.ic

@@ -20,6 +20,7 @@ page_cur_get_page(
 	page_cur_t*	cur)	/* in: page cursor */
 {
 	ut_ad(cur);
+	ut_ad(page_align(cur->rec) == cur->block->frame);
 
 	return(page_align(cur->rec));
 }
@@ -103,6 +104,8 @@ page_cur_is_before_first(
 					/* out: TRUE if at start */
 	const page_cur_t*	cur)	/* in: cursor */
 {
+	ut_ad(cur);
+	ut_ad(page_align(cur->rec) == cur->block->frame);
 	return(page_rec_is_infimum(cur->rec));
 }
 
@@ -115,6 +118,8 @@ page_cur_is_after_last(
 					/* out: TRUE if at end */
 	const page_cur_t*	cur)	/* in: cursor */
 {
+	ut_ad(cur);
+	ut_ad(page_align(cur->rec) == cur->block->frame);
 	return(page_rec_is_supremum(cur->rec));
 }
 
@@ -182,13 +187,15 @@ UNIV_INLINE
 ulint
 page_cur_search(
 /*============*/
-				/* out: number of matched fields on the left */
+					/* out: number of matched
-	buf_block_t*	block,	/* in: buffer block */
+					fields on the left */
-	dict_index_t*	index,	/* in: record descriptor */
+	const buf_block_t*	block,	/* in: buffer block */
-	const dtuple_t*	tuple,	/* in: data tuple */
+	const dict_index_t*	index,	/* in: record descriptor */
-	ulint		mode,	/* in: PAGE_CUR_L, PAGE_CUR_LE, PAGE_CUR_G,
+	const dtuple_t*		tuple,	/* in: data tuple */
-				or PAGE_CUR_GE */
+	ulint			mode,	/* in: PAGE_CUR_L,
-	page_cur_t*	cursor)	/* out: page cursor */
+					PAGE_CUR_LE, PAGE_CUR_G, or
+					PAGE_CUR_GE */
+	page_cur_t*		cursor)	/* out: page cursor */
 {
 	ulint		low_matched_fields = 0;
 	ulint		low_matched_bytes = 0;

row/row0merge.c

@@ -1127,12 +1127,12 @@ row_merge_read_clustered_index(
 		row_ext_t*	ext;
 		ibool		has_next	= TRUE;
 
-		btr_pcur_move_to_next_on_page(&pcur, &mtr);
+		btr_pcur_move_to_next_on_page(&pcur);
 
 		/* When switching pages, commit the mini-transaction
 		in order to release the latch on the old page. */
 
-		if (btr_pcur_is_after_last_on_page(&pcur, &mtr)) {
+		if (btr_pcur_is_after_last_on_page(&pcur)) {
 			btr_pcur_store_position(&pcur, &mtr);
 			mtr_commit(&mtr);
 			mtr_start(&mtr);

row/row0mysql.c

@@ -2928,7 +2928,7 @@ row_truncate_table_for_mysql(
 		ulint		len;
 		ulint		root_page_no;
 
-		if (!btr_pcur_is_on_user_rec(&pcur, &mtr)) {
+		if (!btr_pcur_is_on_user_rec(&pcur)) {
 			/* The end of SYS_INDEXES has been reached. */
 			break;
 		}

row/row0sel.c

@@ -1752,7 +1752,7 @@ next_rec:
 	}
 
 	if (leaf_contains_updates
-	    && btr_pcur_is_after_last_on_page(&(plan->pcur), &mtr)) {
+	    && btr_pcur_is_after_last_on_page(&plan->pcur)) {
 
 		/* We must commit &mtr if we are moving to a different page,
 		because we have done updates to the x-latched leaf page, and
@@ -1785,7 +1785,7 @@ next_table:
 	/* We found a record which satisfies the conditions: we can move to
 	the next table or return a row in the result set */
 
-	ut_ad(btr_pcur_is_on_user_rec(&(plan->pcur), &mtr));
+	ut_ad(btr_pcur_is_on_user_rec(&plan->pcur));
 
 	if (plan->unique_search && !node->can_get_updated) {
 
@@ -1922,8 +1922,7 @@ commit_mtr_for_a_while:
 lock_wait_or_error:
 	/* See the note at stop_for_a_while: the same holds for this case */
 
-	ut_ad(!btr_pcur_is_before_first_on_page(&(plan->pcur), &mtr)
+	ut_ad(!btr_pcur_is_before_first_on_page(&plan->pcur) || !node->asc);
-	      || !node->asc);
 	ut_ad(!search_latch_locked);
 
 	plan->stored_cursor_rec_processed = FALSE;
@@ -3065,7 +3064,7 @@ sel_restore_position_for_mysql(
 			return(TRUE);
 		}
 
-		if (btr_pcur_is_on_user_rec(pcur, mtr)) {
+		if (btr_pcur_is_on_user_rec(pcur)) {
 			btr_pcur_move_to_prev(pcur, mtr);
 		}
 
@@ -3075,7 +3074,7 @@ sel_restore_position_for_mysql(
 	ut_ad(relative_position == BTR_PCUR_BEFORE
 	      || relative_position == BTR_PCUR_BEFORE_FIRST_IN_TREE);
 
-	if (moves_up && btr_pcur_is_on_user_rec(pcur, mtr)) {
+	if (moves_up && btr_pcur_is_on_user_rec(pcur)) {
 		btr_pcur_move_to_next(pcur, mtr);
 	}