Slightly simplify nbtree split point choice loop.

petergeoghegan · petergeoghegan · commit f0ca378d4c13 · 2020-04-15T15:47:26.000-07:00
Spotted during post-commit review of the nbtree deduplication commit (commit 0d861bb).
diff --git a/src/backend/access/nbtree/nbtsplitloc.c b/src/backend/access/nbtree/nbtsplitloc.c
@@ -820,18 +820,14 @@ _bt_bestsplitloc(FindSplitData *state, int perfectpenalty,
 
 		penalty = _bt_split_penalty(state, state->splits + i);
 
-		if (penalty <= perfectpenalty)
-		{
-			bestpenalty = penalty;
-			lowsplit = i;
-			break;
-		}
-
 		if (penalty < bestpenalty)
 		{
 			bestpenalty = penalty;
 			lowsplit = i;
 		}
+
+		if (penalty <= perfectpenalty)
+			break;
 	}
 
 	final = &state->splits[lowsplit];

Original file line number	Diff line number	Diff line change
`@@ -820,18 +820,14 @@ _bt_bestsplitloc(FindSplitData *state, int perfectpenalty,`
`820`	`820`
`821`	`821`	`penalty = _bt_split_penalty(state, state->splits + i);`
`822`	`822`
`823`		`- if (penalty <= perfectpenalty)`
`824`		`- {`
`825`		`- bestpenalty = penalty;`
`826`		`- lowsplit = i;`
`827`		`- break;`
`828`		`- }`
`829`		`-`
`830`	`823`	`if (penalty < bestpenalty)`
`831`	`824`	`{`
`832`	`825`	`bestpenalty = penalty;`
`833`	`826`	`lowsplit = i;`
`834`	`827`	`}`
	`828`	`+`
	`829`	`+ if (penalty <= perfectpenalty)`
	`830`	`+ break;`
`835`	`831`	`}`
`836`	`832`
`837`	`833`	`final = &state->splits[lowsplit];`