diff options
| author | 2024-05-27 09:22:31 +0000 | |
|---|---|---|
| committer | 2024-05-28 10:24:57 +0000 | |
| commit | 57bccc788b13fa01b25638c69db38cf1114332cf (patch) | |
| tree | 2829a7ee347b06266911e1f504480b2f94d5d405 | |
| parent | 9218537220693562274b3386f0ae8cb52d5f1a49 (diff) | |
Faster `CharacterLowerUpper()`.
Test: m test-art-host-gtest
Test: testrunner.py --host --optimizing
Bug: 181943478
Change-Id: I15a69c2dce8afe46c175ee6a87feefe493b99115
| -rw-r--r-- | runtime/interpreter/unstarted_runtime.cc | 20 |
1 files changed, 11 insertions, 9 deletions
diff --git a/runtime/interpreter/unstarted_runtime.cc b/runtime/interpreter/unstarted_runtime.cc index d83f5378fd..43e0692eee 100644 --- a/runtime/interpreter/unstarted_runtime.cc +++ b/runtime/interpreter/unstarted_runtime.cc @@ -99,7 +99,7 @@ static void CharacterLowerUpper(Thread* self, JValue* result, size_t arg_offset, bool to_lower_case) REQUIRES_SHARED(Locks::mutator_lock_) { - uint32_t int_value = static_cast<uint32_t>(shadow_frame->GetVReg(arg_offset)); + int32_t int_value = shadow_frame->GetVReg(arg_offset); // Only ASCII (7-bit). if (!isascii(int_value)) { @@ -109,14 +109,16 @@ static void CharacterLowerUpper(Thread* self, return; } - std::locale c_locale("C"); - char char_value = static_cast<char>(int_value); - - if (to_lower_case) { - result->SetI(std::tolower(char_value, c_locale)); - } else { - result->SetI(std::toupper(char_value, c_locale)); - } + // Constructing a `std::locale("C")` is slow. Use an explicit calculation, compare in debug mode. + int32_t masked_value = int_value & ~0x20; // Clear bit distinguishing `A`..`Z` from `a`..`z`. + bool is_ascii_letter = ('A' <= masked_value) && (masked_value <= 'Z'); + int32_t result_value = is_ascii_letter ? (masked_value | (to_lower_case ? 0x20 : 0)) : int_value; + DCHECK_EQ(result_value, + to_lower_case + ? std::tolower(dchecked_integral_cast<char>(int_value), std::locale("C")) + : std::toupper(dchecked_integral_cast<char>(int_value), std::locale("C"))) + << std::boolalpha << to_lower_case; + result->SetI(result_value); } void UnstartedRuntime::UnstartedCharacterToLowerCase( |