From 697c47a7ffd4489c4bc4edc229c8123309526286 Mon Sep 17 00:00:00 2001 From: David Srbecky Date: Sun, 16 Jun 2019 21:53:07 +0100 Subject: Stack maps: Handle special cases using flags. Keep the BitTable decoder simple (1+NumColumns varints). Move special case handling up to CodeInfo (empty/dedup). This speeds up CodeInfo by 5%, and maps startup by 0.05%. Change in size is negligible (the bits mostly just move). Test: test.py -b --host --64 --optimizing Change-Id: Ib6abe52f04384de9ffd7cfba04a3124b62f713ff --- compiler/optimizing/stack_map_stream.cc | 31 +++++++++++++++---------------- 1 file changed, 15 insertions(+), 16 deletions(-) (limited to 'compiler/optimizing/stack_map_stream.cc') diff --git a/compiler/optimizing/stack_map_stream.cc b/compiler/optimizing/stack_map_stream.cc index e21e21cdf3..87702cc798 100644 --- a/compiler/optimizing/stack_map_stream.cc +++ b/compiler/optimizing/stack_map_stream.cc @@ -184,7 +184,6 @@ void StackMapStream::BeginInlineInfoEntry(ArtMethod* method, in_inline_info_ = true; DCHECK_EQ(expected_num_dex_registers_, current_dex_registers_.size()); - flags_ |= CodeInfo::kHasInlineInfo; expected_num_dex_registers_ += num_dex_registers; BitTableBuilder::Entry entry; @@ -294,31 +293,31 @@ void StackMapStream::CreateDexRegisterMap() { } } -template -ALWAYS_INLINE static void EncodeTable(Writer& out, const Builder& bit_table) { - out.WriteBit(false); // Is not deduped. - bit_table.Encode(out); -} - ScopedArenaVector StackMapStream::Encode() { DCHECK(in_stack_map_ == false) << "Mismatched Begin/End calls"; DCHECK(in_inline_info_ == false) << "Mismatched Begin/End calls"; + uint32_t flags = (inline_infos_.size() > 0) ? CodeInfo::kHasInlineInfo : 0; + uint32_t bit_table_flags = 0; + ForEachBitTable([&bit_table_flags](size_t i, auto bit_table) { + if (bit_table->size() != 0) { // Record which bit-tables are stored. + bit_table_flags |= 1 << i; + } + }); + ScopedArenaVector buffer(allocator_->Adapter(kArenaAllocStackMapStream)); BitMemoryWriter> out(&buffer); - out.WriteVarint(flags_); + out.WriteVarint(flags); out.WriteVarint(packed_frame_size_); out.WriteVarint(core_spill_mask_); out.WriteVarint(fp_spill_mask_); out.WriteVarint(num_dex_registers_); - EncodeTable(out, stack_maps_); - EncodeTable(out, register_masks_); - EncodeTable(out, stack_masks_); - EncodeTable(out, inline_infos_); - EncodeTable(out, method_infos_); - EncodeTable(out, dex_register_masks_); - EncodeTable(out, dex_register_maps_); - EncodeTable(out, dex_register_catalog_); + out.WriteVarint(bit_table_flags); + ForEachBitTable([&out](size_t, auto bit_table) { + if (bit_table->size() != 0) { // Skip empty bit-tables. + bit_table->Encode(out); + } + }); // Verify that we can load the CodeInfo and check some essentials. CodeInfo code_info(buffer.data()); -- cgit v1.2.3-59-g8ed1b