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| author | 2016-09-09 19:01:32 -0700 | |
|---|---|---|
| committer | 2016-09-30 10:51:50 -0700 | |
| commit | 0576575d075e97a227010b4adf74ad5c8a920bde (patch) | |
| tree | c31eb030933e74d6d103979bcf0d1226e769eb5b /compiler/optimizing/instruction_simplifier_arm.cc | |
| parent | 9e5739aaa690a8529c104f4c05035a657616c310 (diff) | |
String Compression for ARM and ARM64
Changes on intrinsics and Code Generation on ARM and ARM64
for string compression feature. Currently the feature is off.
The size of boot.oat and boot.art for ARM before and after the
changes (feature OFF) are still. When the feature ON,
boot.oat increased by 0.60% and boot.art decreased by 9.38%.
Meanwhile for ARM64, size of boot.oat and boot.art before and
after changes (feature OFF) are still. When the feature ON,
boot.oat increased by 0.48% and boot.art decreased by 6.58%.
Turn feature on: runtime/mirror/string.h (kUseStringCompression = true)
runtime/asm_support.h (STRING_COMPRESSION_FEATURE 1)
Test: m -j31 test-art-target
All tests passed both when the mirror::kUseStringCompression
is ON and OFF.
Bug: 31040547
Change-Id: I24e86b99391df33ba27df747779b648c5a820649
Diffstat (limited to 'compiler/optimizing/instruction_simplifier_arm.cc')
| -rw-r--r-- | compiler/optimizing/instruction_simplifier_arm.cc | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/compiler/optimizing/instruction_simplifier_arm.cc b/compiler/optimizing/instruction_simplifier_arm.cc index 495f3fd232..56e4c7a9c2 100644 --- a/compiler/optimizing/instruction_simplifier_arm.cc +++ b/compiler/optimizing/instruction_simplifier_arm.cc @@ -44,6 +44,14 @@ void InstructionSimplifierArmVisitor::VisitArrayGet(HArrayGet* instruction) { size_t data_offset = CodeGenerator::GetArrayDataOffset(instruction); Primitive::Type type = instruction->GetType(); + // TODO: Implement reading (length + compression) for String compression feature from + // negative offset (count_offset - data_offset). Thumb2Assembler does not support T4 + // encoding of "LDR (immediate)" at the moment. + // Don't move array pointer if it is charAt because we need to take the count first. + if (mirror::kUseStringCompression && instruction->IsStringCharAt()) { + return; + } + if (type == Primitive::kPrimLong || type == Primitive::kPrimFloat || type == Primitive::kPrimDouble) { |