Remove isTextNode optimization

Summary: Scrolling through feed and logging when this optimization is hit leads to... 0 logs. If anything this just adds to confusion. It was initially added due to instinct and not data, which was a mistake. I am happy to add some similar optimization in the future if we have data that it is useful in real world situations, currently it just leads to bugs and confusion though.

Reviewed By: astreet

Differential Revision: D4146785

fbshipit-source-id: e20d780fbd5759b8f38b809e8cadf29cedee82a8
This commit is contained in:
Emil Sjolander
2016-11-08 09:07:48 -08:00
committed by Facebook Github Bot
parent b50090a04e
commit 1baa239389
10 changed files with 7 additions and 122 deletions

View File

@@ -240,7 +240,6 @@ public class LayoutEngine {
}
/*package*/ static boolean canUseCachedMeasurement(
boolean isTextNode,
float availableWidth,
float availableHeight,
float marginRow,
@@ -281,38 +280,6 @@ public class LayoutEngine {
return true;
}
// We know this to be text so we can apply some more specialized heuristics.
if (isTextNode) {
if (isWidthSame) {
if (heightMeasureMode == CSSMeasureMode.UNDEFINED) {
// Width is the same and height is not restricted. Re-use cahced value.
return true;
}
if (heightMeasureMode == CSSMeasureMode.AT_MOST &&
cachedLayout.computedHeight < (availableHeight - marginColumn)) {
// Width is the same and height restriction is greater than the cached height. Re-use cached value.
return true;
}
// Width is the same but height restriction imposes smaller height than previously measured.
// Update the cached value to respect the new height restriction.
cachedLayout.computedHeight = availableHeight - marginColumn;
return true;
}
if (cachedLayout.widthMeasureMode == CSSMeasureMode.UNDEFINED) {
if (widthMeasureMode == CSSMeasureMode.UNDEFINED ||
(widthMeasureMode == CSSMeasureMode.AT_MOST &&
cachedLayout.computedWidth <= (availableWidth - marginRow))) {
// Previsouly this text was measured with no width restriction, if width is now restricted
// but to a larger value than the previsouly measured width we can re-use the measurement
// as we know it will fit.
return true;
}
}
}
return false;
}
@@ -364,13 +331,13 @@ public class LayoutEngine {
node.style.margin.getWithFallback(trailingSpacing[CSS_FLEX_DIRECTION_COLUMN], trailing[CSS_FLEX_DIRECTION_COLUMN]);
// First, try to use the layout cache.
if (canUseCachedMeasurement(node.isTextNode(), availableWidth, availableHeight, marginAxisRow, marginAxisColumn,
if (canUseCachedMeasurement(availableWidth, availableHeight, marginAxisRow, marginAxisColumn,
widthMeasureMode, heightMeasureMode, layout.cachedLayout)) {
cachedResults = layout.cachedLayout;
} else {
// Try to use the measurement cache.
for (int i = 0; i < layout.nextCachedMeasurementsIndex; i++) {
if (canUseCachedMeasurement(node.isTextNode(), availableWidth, availableHeight, marginAxisRow, marginAxisColumn,
if (canUseCachedMeasurement(availableWidth, availableHeight, marginAxisRow, marginAxisColumn,
widthMeasureMode, heightMeasureMode, layout.cachedMeasurements[i])) {
cachedResults = layout.cachedMeasurements[i];
break;