From c7685d2f99883b6360597c1a8f0268882d01e602 Mon Sep 17 00:00:00 2001 From: "dusan.milosavljevic" Date: Fri, 3 Apr 2015 11:02:17 -0700 Subject: [PATCH] MIPS64: Improve deopt jump table code size. The number of generated instructions per table entry is reduced from six to two, or four in worst-case scenario. TEST= BUG= Review URL: https://codereview.chromium.org/1059213002 Cr-Commit-Position: refs/heads/master@{#27599} --- src/mips64/lithium-codegen-mips64.cc | 110 +++++++++++++++++++++-------------- src/mips64/lithium-codegen-mips64.h | 2 +- 2 files changed, 67 insertions(+), 45 deletions(-) diff --git a/src/mips64/lithium-codegen-mips64.cc b/src/mips64/lithium-codegen-mips64.cc index 3b19379..6154584 100644 --- a/src/mips64/lithium-codegen-mips64.cc +++ b/src/mips64/lithium-codegen-mips64.cc @@ -301,50 +301,71 @@ bool LCodeGen::GenerateDeferredCode() { bool LCodeGen::GenerateJumpTable() { if (jump_table_.length() > 0) { Comment(";;; -------------------- Jump table --------------------"); - } - Assembler::BlockTrampolinePoolScope block_trampoline_pool(masm_); - Label table_start, call_deopt_entry; - __ bind(&table_start); - Label needs_frame; - for (int i = 0; i < jump_table_.length(); i++) { - Deoptimizer::JumpTableEntry* table_entry = &jump_table_[i]; - __ bind(&table_entry->label); - Address entry = table_entry->address; - DeoptComment(table_entry->deopt_info); - __ li(t9, Operand(ExternalReference::ForDeoptEntry(entry))); - if (table_entry->needs_frame) { - DCHECK(!info()->saves_caller_doubles()); - Comment(";;; call deopt with frame"); - __ MultiPush(cp.bit() | fp.bit() | ra.bit()); - __ Call(&needs_frame); - } else { - __ Call(&call_deopt_entry); - } - info()->LogDeoptCallPosition(masm()->pc_offset(), - table_entry->deopt_info.inlining_id); - } - if (needs_frame.is_linked()) { - __ bind(&needs_frame); - // This variant of deopt can only be used with stubs. Since we don't - // have a function pointer to install in the stack frame that we're - // building, install a special marker there instead. - DCHECK(info()->IsStub()); - __ li(at, Operand(Smi::FromInt(StackFrame::STUB))); - __ push(at); - __ Daddu(fp, sp, Operand(StandardFrameConstants::kFixedFrameSizeFromFp)); - } + Assembler::BlockTrampolinePoolScope block_trampoline_pool(masm_); + Label table_start, call_deopt_entry; + + __ bind(&table_start); + Label needs_frame; + Address base = jump_table_[0]->address; + for (int i = 0; i < jump_table_.length(); i++) { + Deoptimizer::JumpTableEntry* table_entry = jump_table_[i]; + __ bind(&table_entry->label); + Address entry = table_entry->address; + DeoptComment(table_entry->deopt_info); + + // Second-level deopt table entries are contiguous and small, so instead + // of loading the full, absolute address of each one, load the base + // address and add an immediate offset. + if (is_int16(entry - base)) { + if (table_entry->needs_frame) { + DCHECK(!info()->saves_caller_doubles()); + Comment(";;; call deopt with frame"); + __ MultiPush(cp.bit() | fp.bit() | ra.bit()); + __ BranchAndLink(&needs_frame, USE_DELAY_SLOT); + __ li(t9, Operand(entry - base)); + } else { + __ BranchAndLink(&call_deopt_entry, USE_DELAY_SLOT); + __ li(t9, Operand(entry - base)); + } - Comment(";;; call deopt"); - __ bind(&call_deopt_entry); + } else { + __ li(t9, Operand(entry - base)); + if (table_entry->needs_frame) { + DCHECK(!info()->saves_caller_doubles()); + Comment(";;; call deopt with frame"); + __ MultiPush(cp.bit() | fp.bit() | ra.bit()); + __ BranchAndLink(&needs_frame); + } else { + __ BranchAndLink(&call_deopt_entry); + } + } + info()->LogDeoptCallPosition(masm()->pc_offset(), + table_entry->deopt_info.inlining_id); + } + if (needs_frame.is_linked()) { + __ bind(&needs_frame); + // This variant of deopt can only be used with stubs. Since we don't + // have a function pointer to install in the stack frame that we're + // building, install a special marker there instead. + DCHECK(info()->IsStub()); + __ li(at, Operand(Smi::FromInt(StackFrame::STUB))); + __ push(at); + __ Daddu(fp, sp, Operand(StandardFrameConstants::kFixedFrameSizeFromFp)); + } - if (info()->saves_caller_doubles()) { - DCHECK(info()->IsStub()); - RestoreCallerDoubles(); - } - __ Jump(t9); + Comment(";;; call deopt"); + __ bind(&call_deopt_entry); - __ RecordComment("]"); + if (info()->saves_caller_doubles()) { + DCHECK(info()->IsStub()); + RestoreCallerDoubles(); + } + __ li(at, + Operand(reinterpret_cast(base), RelocInfo::RUNTIME_ENTRY)); + __ Daddu(t9, t9, Operand(at)); + __ Jump(t9); + } // The deoptimization jump table is the last part of the instruction // sequence. Mark the generated code as done unless we bailed out. if (!is_aborted()) status_ = DONE; @@ -824,16 +845,17 @@ void LCodeGen::DeoptimizeIf(Condition condition, LInstruction* instr, __ Call(entry, RelocInfo::RUNTIME_ENTRY, condition, src1, src2); info()->LogDeoptCallPosition(masm()->pc_offset(), deopt_info.inlining_id); } else { - Deoptimizer::JumpTableEntry table_entry(entry, deopt_info, bailout_type, - !frame_is_built_); + Deoptimizer::JumpTableEntry* table_entry = + new (zone()) Deoptimizer::JumpTableEntry( + entry, deopt_info, bailout_type, !frame_is_built_); // We often have several deopts to the same entry, reuse the last // jump entry if this is the case. if (FLAG_trace_deopt || isolate()->cpu_profiler()->is_profiling() || jump_table_.is_empty() || - !table_entry.IsEquivalentTo(jump_table_.last())) { + !table_entry->IsEquivalentTo(*jump_table_.last())) { jump_table_.Add(table_entry, zone()); } - __ Branch(&jump_table_.last().label, condition, src1, src2); + __ Branch(&jump_table_.last()->label, condition, src1, src2); } } diff --git a/src/mips64/lithium-codegen-mips64.h b/src/mips64/lithium-codegen-mips64.h index 38890b3..8f0e82c 100644 --- a/src/mips64/lithium-codegen-mips64.h +++ b/src/mips64/lithium-codegen-mips64.h @@ -358,7 +358,7 @@ class LCodeGen: public LCodeGenBase { void EmitVectorLoadICRegisters(T* instr); ZoneList deoptimizations_; - ZoneList jump_table_; + ZoneList jump_table_; ZoneList > deoptimization_literals_; int inlined_function_count_; Scope* const scope_; -- 2.7.4