From 3c19d3e029a9fcc123d2c6fd1e5e13867d2cfe1f Mon Sep 17 00:00:00 2001 From: Vladimir Marko Date: Tue, 19 Apr 2016 14:36:35 +0100 Subject: Reuse HUseListNode<>s when replacing instruction or input. Compiling the Nexus 5 boot image with the 64-bit dex2oat on host this CL reduces the memory used for compiling the most hungry method, BatteryStats.dumpLocked(), by ~5.6MiB: Before: MEM: used: 44393040, allocated: 45361248, lost: 968208 Number of arenas allocated: 319, Number of allocations: 815492, avg size: 54 ... UseListNode 10308480 ... After: MEM: used: 38554536, allocated: 39463008, lost: 908472 Number of arenas allocated: 274, Number of allocations: 572221, avg size: 67 ... UseListNode 4469976 ... With 32-bit dex2oat, the UseListNode would be 2/3 of the values for 64-bit dex2oat (both before and after). Bug: 28173563 Change-Id: Ia4fabe03568f0e0dbf2cdf2b031863602aea3530 --- compiler/optimizing/nodes.cc | 39 ++++++++++++++++++++++----------------- compiler/optimizing/ssa_test.cc | 2 +- 2 files changed, 23 insertions(+), 18 deletions(-) (limited to 'compiler/optimizing') diff --git a/compiler/optimizing/nodes.cc b/compiler/optimizing/nodes.cc index d259c21108..7c6e9318fb 100644 --- a/compiler/optimizing/nodes.cc +++ b/compiler/optimizing/nodes.cc @@ -1005,28 +1005,33 @@ void HInstruction::RemoveEnvironment() { void HInstruction::ReplaceWith(HInstruction* other) { DCHECK(other != nullptr); - for (const HUseListNode& use : GetUses()) { - HInstruction* user = use.GetUser(); - size_t input_index = use.GetIndex(); - user->SetRawInputAt(input_index, other); - other->AddUseAt(user, input_index); - } + // Note: fixup_end remains valid across splice_after(). + auto fixup_end = other->uses_.empty() ? other->uses_.begin() : ++other->uses_.begin(); + other->uses_.splice_after(other->uses_.before_begin(), uses_); + other->FixUpUserRecordsAfterUseInsertion(fixup_end); - for (const HUseListNode& use : GetEnvUses()) { - HEnvironment* user = use.GetUser(); - size_t input_index = use.GetIndex(); - user->SetRawEnvAt(input_index, other); - other->AddEnvUseAt(user, input_index); - } + // Note: env_fixup_end remains valid across splice_after(). + auto env_fixup_end = + other->env_uses_.empty() ? other->env_uses_.begin() : ++other->env_uses_.begin(); + other->env_uses_.splice_after(other->env_uses_.before_begin(), env_uses_); + other->FixUpUserRecordsAfterEnvUseInsertion(env_fixup_end); - uses_.clear(); - env_uses_.clear(); + DCHECK(uses_.empty()); + DCHECK(env_uses_.empty()); } void HInstruction::ReplaceInput(HInstruction* replacement, size_t index) { - RemoveAsUserOfInput(index); - SetRawInputAt(index, replacement); - replacement->AddUseAt(this, index); + HUserRecord input_use = InputRecordAt(index); + HUseList::iterator before_use_node = input_use.GetBeforeUseNode(); + DCHECK(input_use.GetInstruction() != replacement); + // Note: fixup_end remains valid across splice_after(). + auto fixup_end = + replacement->uses_.empty() ? replacement->uses_.begin() : ++replacement->uses_.begin(); + replacement->uses_.splice_after(replacement->uses_.before_begin(), + input_use.GetInstruction()->uses_, + before_use_node); + replacement->FixUpUserRecordsAfterUseInsertion(fixup_end); + input_use.GetInstruction()->FixUpUserRecordsAfterUseRemoval(before_use_node); } size_t HInstruction::EnvironmentSize() const { diff --git a/compiler/optimizing/ssa_test.cc b/compiler/optimizing/ssa_test.cc index 218bd53bc2..429763423c 100644 --- a/compiler/optimizing/ssa_test.cc +++ b/compiler/optimizing/ssa_test.cc @@ -346,7 +346,7 @@ TEST_F(SsaTest, Loop5) { "BasicBlock 7, pred: 6\n" " 12: Exit\n" "BasicBlock 8, pred: 2, 3, succ: 4\n" - " 13: Phi(2, 1) [8, 8, 11]\n" + " 13: Phi(2, 1) [11, 8, 8]\n" " 14: Goto\n"; const uint16_t data[] = ONE_REGISTER_CODE_ITEM( -- cgit v1.2.3-59-g8ed1b