Optimize path/text evaluation in ninja lexer by using equals instead of set lookup
RELNOTES: None.
PiperOrigin-RevId: 309225814
diff --git a/src/main/java/com/google/devtools/build/lib/bazel/rules/ninja/lexer/NinjaLexerStep.java b/src/main/java/com/google/devtools/build/lib/bazel/rules/ninja/lexer/NinjaLexerStep.java
index 73a288d..025a517 100644
--- a/src/main/java/com/google/devtools/build/lib/bazel/rules/ninja/lexer/NinjaLexerStep.java
+++ b/src/main/java/com/google/devtools/build/lib/bazel/rules/ninja/lexer/NinjaLexerStep.java
@@ -46,9 +46,14 @@
public class NinjaLexerStep {
private static final ImmutableSortedSet<Byte> IDENTIFIER_SYMBOLS =
createByteSet("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_-");
- private static final ImmutableSortedSet<Byte> TEXT_STOPPERS = createByteSet("\n\r \t$:\u0000");
+ private static final byte[] TEXT_STOPPERS = createByteArray("\n\r \t$:\u0000");
// We allow # symbol in the path, so the comment on the line with path can only start with space.
- private static final ImmutableSortedSet<Byte> PATH_STOPPERS = createByteSet("\n\r \t$:|\u0000");
+ private static final byte[] PATH_STOPPERS = createByteArray("\n\r \t$:|\u0000");
+
+ private static byte[] createByteArray(String variants) {
+ byte[] bytes = variants.getBytes(StandardCharsets.ISO_8859_1);
+ return bytes;
+ }
private static ImmutableSortedSet<Byte> createByteSet(String variants) {
ImmutableSortedSet.Builder<Byte> builder = ImmutableSortedSet.naturalOrder();
@@ -242,11 +247,57 @@
}
public void readText() {
- end = eatSequence(position, TEXT_STOPPERS::contains);
+ int i = position;
+ for (; i < fragment.length(); i++) {
+ byte b = fragment.byteAt(i);
+ if (0 == b) {
+ seenZero = true;
+ end = i;
+ return;
+ }
+ if (isTextStopper(b)) {
+ break;
+ }
+ }
+ end = i;
}
public void readPath() {
- end = eatSequence(position, PATH_STOPPERS::contains);
+ int i = position;
+ for (; i < fragment.length(); i++) {
+ byte b = fragment.byteAt(i);
+ if (0 == b) {
+ seenZero = true;
+ end = i;
+ return;
+ }
+ if (isPathStopper(b)) {
+ break;
+ }
+ }
+ end = i;
+ }
+
+ // Optimized, since this is run for each byte in the ninja file. (This has better performance
+ // than lookup in a java Set, since TEXT_STOPPERS is small.
+ private static boolean isTextStopper(byte b) {
+ for (int i = 0; i < TEXT_STOPPERS.length; i++) {
+ if (b == TEXT_STOPPERS[i]) {
+ return true;
+ }
+ }
+ return false;
+ }
+
+ // Optimized, since this is run for each byte in the ninja file. (This has better performance
+ // than lookup in a java Set, since PATH_STOPPERS is small.
+ private static boolean isPathStopper(byte b) {
+ for (int i = 0; i < PATH_STOPPERS.length; i++) {
+ if (b == PATH_STOPPERS[i]) {
+ return true;
+ }
+ }
+ return false;
}
private int readIdentifier(int startFrom, boolean withDot) {
