Author: [EMAIL PROTECTED]
Date: Tue Dec 2 01:50:39 2008
New Revision: 887
Modified:
branches/bleeding_edge/src/runtime.cc
Log:
Optimization of single character indexOf. Gives small improvement on
GCC4.2, but large improvement on GCC 4.3 (which was much worse on that
particular code).
Modified: branches/bleeding_edge/src/runtime.cc
==============================================================================
--- branches/bleeding_edge/src/runtime.cc (original)
+++ branches/bleeding_edge/src/runtime.cc Tue Dec 2 01:50:39 2008
@@ -1241,11 +1241,8 @@
template <typename schar>
static int SingleCharIndexOf(Vector<const schar> string,
- uc16 pattern_char,
+ schar pattern_char,
int start_index) {
- if (sizeof(schar) == 1 && pattern_char > String::kMaxAsciiCharCode) {
- return -1;
- }
for (int i = start_index, n = string.length(); i < n; i++) {
if (pattern_char == string[i]) {
return i;
@@ -1380,9 +1377,19 @@
if (pattern_length == 1) {
AssertNoAllocation no_heap_allocation; // ensure vectors stay valid
if (sub_shape.IsAsciiRepresentation()) {
- return SingleCharIndexOf(sub->ToAsciiVector(),
- pat->Get(pat_shape, 0),
- start_index);
+ uc16 pchar = pat->Get(pat_shape, 0);
+ if (pchar > String::kMaxAsciiCharCode) {
+ return -1;
+ }
+ Vector<const char> ascii_vector =
+ sub->ToAsciiVector().SubVector(start_index, subject_length);
+ void* pos = memchr(ascii_vector.start(),
+ static_cast<const char>(pchar),
+ static_cast<size_t>(ascii_vector.length()));
+ if (pos == NULL) {
+ return -1;
+ }
+ return reinterpret_cast<char*>(pos) - ascii_vector.start() +
start_index;
}
return SingleCharIndexOf(sub->ToUC16Vector(),
pat->Get(pat_shape, 0),
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