From 3fb8648bed83c95f601d2c2e20962cbd08bc7dc7 Mon Sep 17 00:00:00 2001 From: Jiaxun Yang Date: Tue, 12 May 2020 12:40:07 +0800 Subject: Bug 1271968 - IonMonkey: MIPS: Replace long jumps by mixed jumps. Tag: #1542 --- js/src/jit/mips64/Assembler-mips64.cpp | 105 +++++++--------------------- js/src/jit/mips64/Assembler-mips64.h | 4 -- js/src/jit/mips64/MacroAssembler-mips64.cpp | 75 +++++++------------- js/src/jit/mips64/MacroAssembler-mips64.h | 12 ++-- 4 files changed, 54 insertions(+), 142 deletions(-) (limited to 'js/src/jit/mips64') diff --git a/js/src/jit/mips64/Assembler-mips64.cpp b/js/src/jit/mips64/Assembler-mips64.cpp index 4d251f152..6d7636309 100644 --- a/js/src/jit/mips64/Assembler-mips64.cpp +++ b/js/src/jit/mips64/Assembler-mips64.cpp @@ -87,7 +87,9 @@ js::jit::SA(FloatRegister r) void jit::PatchJump(CodeLocationJump& jump_, CodeLocationLabel label, ReprotectCode reprotect) { - Instruction* inst = (Instruction*)jump_.raw(); + Instruction* inst; + + inst = AssemblerMIPSShared::GetInstructionImmediateFromJump((Instruction*)jump_.raw()); // Six instructions used in load 64-bit imm. MaybeAutoWritableJitCode awjc(inst, 6 * sizeof(uint32_t), reprotect); @@ -125,23 +127,6 @@ jit::PatchBackedge(CodeLocationJump& jump, CodeLocationLabel label, } } -void -Assembler::executableCopy(uint8_t* buffer) -{ - MOZ_ASSERT(isFinished); - m_buffer.executableCopy(buffer); - - // Patch all long jumps during code copy. - for (size_t i = 0; i < longJumps_.length(); i++) { - Instruction* inst = (Instruction*) ((uintptr_t)buffer + longJumps_[i]); - - uint64_t value = Assembler::ExtractLoad64Value(inst); - Assembler::UpdateLoad64Value(inst, (uint64_t)buffer + value); - } - - AutoFlushICache::setRange(uintptr_t(buffer), m_buffer.size()); -} - uintptr_t Assembler::GetPointer(uint8_t* instPtr) { @@ -247,8 +232,12 @@ void Assembler::bind(InstImm* inst, uintptr_t branch, uintptr_t target) { int64_t offset = target - branch; - InstImm inst_bgezal = InstImm(op_regimm, zero, rt_bgezal, BOffImm16(0)); - InstImm inst_beq = InstImm(op_beq, zero, zero, BOffImm16(0)); + + // Generate the patchable mixed jump for call. + if (inst->extractOpcode() == ((uint32_t)op_jal >> OpcodeShift)) { + addMixedJump(BufferOffset(branch), ImmPtr((void*)target)); + return; + } // If encoded offset is 4, then the jump must be short if (BOffImm16(inst[0]).decode() == 4) { @@ -258,47 +247,14 @@ Assembler::bind(InstImm* inst, uintptr_t branch, uintptr_t target) return; } - // Generate the long jump for calls because return address has to be the - // address after the reserved block. - if (inst[0].encode() == inst_bgezal.encode()) { - addLongJump(BufferOffset(branch)); - Assembler::WriteLoad64Instructions(inst, ScratchRegister, target); - inst[4] = InstReg(op_special, ScratchRegister, zero, ra, ff_jalr).encode(); - // There is 1 nop after this. - return; - } - if (BOffImm16::IsInRange(offset)) { - // Don't skip trailing nops can improve performance - // on Loongson3 platform. - bool skipNops = !isLoongson() && (inst[0].encode() != inst_bgezal.encode() && - inst[0].encode() != inst_beq.encode()); - inst[0].setBOffImm16(BOffImm16(offset)); inst[1].makeNop(); - if (skipNops) { - inst[2] = InstImm(op_regimm, zero, rt_bgez, BOffImm16(5 * sizeof(uint32_t))).encode(); - // There are 4 nops after this - } return; } - if (inst[0].encode() == inst_beq.encode()) { - // Handle long unconditional jump. - addLongJump(BufferOffset(branch)); - Assembler::WriteLoad64Instructions(inst, ScratchRegister, target); - inst[4] = InstReg(op_special, ScratchRegister, zero, zero, ff_jr).encode(); - // There is 1 nop after this. - } else { - // Handle long conditional jump. - inst[0] = invertBranch(inst[0], BOffImm16(7 * sizeof(uint32_t))); - // No need for a "nop" here because we can clobber scratch. - addLongJump(BufferOffset(branch + sizeof(uint32_t))); - Assembler::WriteLoad64Instructions(&inst[1], ScratchRegister, target); - inst[5] = InstReg(op_special, ScratchRegister, zero, zero, ff_jr).encode(); - // There is 1 nop after this. - } + addMixedJump(BufferOffset(branch), ImmPtr((void*)target)); } void @@ -313,19 +269,16 @@ Assembler::bind(RepatchLabel* label) InstImm inst_beq = InstImm(op_beq, zero, zero, BOffImm16(0)); uint64_t offset = dest.getOffset() - label->offset(); - // If first instruction is lui, then this is a long jump. + // If first instruction is j, then this is a mixed jump. // If second instruction is lui, then this is a loop backedge. - if (inst[0].extractOpcode() == (uint32_t(op_lui) >> OpcodeShift)) { - // For unconditional long branches generated by ma_liPatchable, - // such as under: - // jumpWithpatch - Assembler::UpdateLoad64Value(inst, dest.getOffset()); + if (inst[0].extractOpcode() == (uint32_t(op_j) >> OpcodeShift)) { + // For unconditional mixed branches generated by jumpWithPatch + addMixedJump(b, ImmPtr((void*)dest.getOffset()), MixedJumpPatch::PATCHABLE); } else if (inst[1].extractOpcode() == (uint32_t(op_lui) >> OpcodeShift) || BOffImm16::IsInRange(offset)) { // Handle code produced by: // backedgeJump - // branchWithCode MOZ_ASSERT(BOffImm16::IsInRange(offset)); MOZ_ASSERT(inst[0].extractOpcode() == (uint32_t(op_beq) >> OpcodeShift) || inst[0].extractOpcode() == (uint32_t(op_bne) >> OpcodeShift) || @@ -333,34 +286,25 @@ Assembler::bind(RepatchLabel* label) inst[0].extractOpcode() == (uint32_t(op_bgtz) >> OpcodeShift)); inst[0].setBOffImm16(BOffImm16(offset)); } else if (inst[0].encode() == inst_beq.encode()) { - // Handle open long unconditional jumps created by + // Handle open mixed unconditional jumps created by // MacroAssemblerMIPSShared::ma_b(..., wasm::Trap, ...). - // We need to add it to long jumps array here. + // We need to add it to mixed jumps array here. // See MacroAssemblerMIPS64::branchWithCode(). MOZ_ASSERT(inst[1].encode() == NopInst); - MOZ_ASSERT(inst[2].encode() == NopInst); - MOZ_ASSERT(inst[3].encode() == NopInst); - MOZ_ASSERT(inst[4].encode() == NopInst); - MOZ_ASSERT(inst[5].encode() == NopInst); - addLongJump(BufferOffset(label->offset())); - Assembler::WriteLoad64Instructions(inst, ScratchRegister, dest.getOffset()); - inst[4] = InstReg(op_special, ScratchRegister, zero, zero, ff_jr).encode(); + addMixedJump(b, ImmPtr((void*)dest.getOffset()), MixedJumpPatch::PATCHABLE); + inst[0] = InstJump(op_j, JOffImm26(0)).encode(); } else { - // Handle open long conditional jumps created by + // Handle open mixed conditional jumps created by // MacroAssemblerMIPSShared::ma_b(..., wasm::Trap, ...). - inst[0] = invertBranch(inst[0], BOffImm16(7 * sizeof(uint32_t))); + inst[0] = invertBranch(inst[0], BOffImm16(4 * sizeof(uint32_t))); // No need for a "nop" here because we can clobber scratch. - // We need to add it to long jumps array here. + // We need to add it to mixed jumps array here. // See MacroAssemblerMIPS64::branchWithCode(). MOZ_ASSERT(inst[1].encode() == NopInst); MOZ_ASSERT(inst[2].encode() == NopInst); MOZ_ASSERT(inst[3].encode() == NopInst); - MOZ_ASSERT(inst[4].encode() == NopInst); - MOZ_ASSERT(inst[5].encode() == NopInst); - MOZ_ASSERT(inst[6].encode() == NopInst); - addLongJump(BufferOffset(label->offset() + sizeof(uint32_t))); - Assembler::WriteLoad64Instructions(&inst[1], ScratchRegister, dest.getOffset()); - inst[5] = InstReg(op_special, ScratchRegister, zero, zero, ff_jr).encode(); + addMixedJump(b, ImmPtr((void*)dest.getOffset()), MixedJumpPatch::PATCHABLE); + inst[2] = InstJump(op_j, JOffImm26(0)).encode(); } } label->bind(dest.getOffset()); @@ -492,8 +436,7 @@ Assembler::PatchDataWithValueCheck(CodeLocationLabel label, PatchedImmPtr newVal void Assembler::PatchInstructionImmediate(uint8_t* code, PatchedImmPtr imm) { - InstImm* inst = (InstImm*)code; - Assembler::UpdateLoad64Value(inst, (uint64_t)imm.value); + Assembler::UpdateLoad64Value((Instruction*)code, (uint64_t)imm.value); } uint64_t diff --git a/js/src/jit/mips64/Assembler-mips64.h b/js/src/jit/mips64/Assembler-mips64.h index 8a71c57bb..5cb9d1239 100644 --- a/js/src/jit/mips64/Assembler-mips64.h +++ b/js/src/jit/mips64/Assembler-mips64.h @@ -153,10 +153,6 @@ class Assembler : public AssemblerMIPSShared void bind(InstImm* inst, uintptr_t branch, uintptr_t target); - // Copy the assembly code to the given buffer, and perform any pending - // relocations relying on the target address. - void executableCopy(uint8_t* buffer); - static uint32_t PatchWrite_NearCallSize(); static uint64_t ExtractLoad64Value(Instruction* inst0); diff --git a/js/src/jit/mips64/MacroAssembler-mips64.cpp b/js/src/jit/mips64/MacroAssembler-mips64.cpp index c35723d74..137a24b59 100644 --- a/js/src/jit/mips64/MacroAssembler-mips64.cpp +++ b/js/src/jit/mips64/MacroAssembler-mips64.cpp @@ -757,36 +757,27 @@ MacroAssemblerMIPS64::ma_b(Address addr, ImmGCPtr imm, Label* label, Condition c } void -MacroAssemblerMIPS64::ma_bal(Label* label, DelaySlotFill delaySlotFill) +MacroAssemblerMIPS64::ma_jal(Label* label) { if (label->bound()) { - // Generate the long jump for calls because return address has to be - // the address after the reserved block. - addLongJump(nextOffset()); - ma_liPatchable(ScratchRegister, ImmWord(label->offset())); - as_jalr(ScratchRegister); - if (delaySlotFill == FillDelaySlot) - as_nop(); + // Generate the mixed jump. + addMixedJump(nextOffset(), ImmPtr((void*)label->offset())); + as_jal(JOffImm26(0)); + as_nop(); return; } // Second word holds a pointer to the next branch in label's chain. uint32_t nextInChain = label->used() ? label->offset() : LabelBase::INVALID_OFFSET; - // Make the whole branch continous in the buffer. The '6' + // Make the whole branch continous in the buffer. The '2' // instructions are writing at below (contain delay slot). - m_buffer.ensureSpace(6 * sizeof(uint32_t)); + m_buffer.ensureSpace(2 * sizeof(uint32_t)); - BufferOffset bo = writeInst(getBranchCode(BranchIsCall).encode()); + BufferOffset bo = as_jal(JOffImm26(0)); writeInst(nextInChain); if (!oom()) label->use(bo.getOffset()); - // Leave space for long jump. - as_nop(); - as_nop(); - as_nop(); - if (delaySlotFill == FillDelaySlot) - as_nop(); } void @@ -810,21 +801,19 @@ MacroAssemblerMIPS64::branchWithCode(InstImm code, Label* label, JumpKind jumpKi } if (code.encode() == inst_beq.encode()) { - // Handle long jump - addLongJump(nextOffset()); - ma_liPatchable(ScratchRegister, ImmWord(label->offset())); - as_jr(ScratchRegister); + // Handle mixed jump + addMixedJump(nextOffset(), ImmPtr((void*)label->offset())); + as_j(JOffImm26(0)); as_nop(); return; } // Handle long conditional branch, the target offset is based on self, // point to next instruction of nop at below. - writeInst(invertBranch(code, BOffImm16(7 * sizeof(uint32_t))).encode()); - // No need for a "nop" here because we can clobber scratch. - addLongJump(nextOffset()); - ma_liPatchable(ScratchRegister, ImmWord(label->offset())); - as_jr(ScratchRegister); + writeInst(invertBranch(code, BOffImm16(4 * sizeof(uint32_t))).encode()); + as_nop(); + addMixedJump(nextOffset(), ImmPtr((void*)label->offset())); + as_j(JOffImm26(0)); as_nop(); return; } @@ -834,36 +823,21 @@ MacroAssemblerMIPS64::branchWithCode(InstImm code, Label* label, JumpKind jumpKi // Second word holds a pointer to the next branch in label's chain. uint32_t nextInChain = label->used() ? label->offset() : LabelBase::INVALID_OFFSET; - if (jumpKind == ShortJump) { - // Make the whole branch continous in the buffer. - m_buffer.ensureSpace(2 * sizeof(uint32_t)); + // Make the whole branch continous in the buffer. + m_buffer.ensureSpace(4 * sizeof(uint32_t)); + if (jumpKind == ShortJump) { // Indicate that this is short jump with offset 4. code.setBOffImm16(BOffImm16(4)); - BufferOffset bo = writeInst(code.encode()); - writeInst(nextInChain); - if (!oom()) - label->use(bo.getOffset()); - return; } - - bool conditional = code.encode() != inst_beq.encode(); - - // Make the whole branch continous in the buffer. The '7' - // instructions are writing at below (contain conditional nop). - m_buffer.ensureSpace(7 * sizeof(uint32_t)); - BufferOffset bo = writeInst(code.encode()); writeInst(nextInChain); if (!oom()) label->use(bo.getOffset()); - // Leave space for potential long jump. - as_nop(); - as_nop(); - as_nop(); - as_nop(); - if (conditional) + if (jumpKind != ShortJump && code.encode() != inst_beq.encode()) { as_nop(); + as_nop(); + } } void @@ -1844,13 +1818,12 @@ MacroAssemblerMIPS64Compat::jumpWithPatch(RepatchLabel* label, Label* documentat { // Only one branch per label. MOZ_ASSERT(!label->used()); - uint32_t dest = label->bound() ? label->offset() : LabelBase::INVALID_OFFSET; BufferOffset bo = nextOffset(); label->use(bo.getOffset()); - addLongJump(bo); - ma_liPatchable(ScratchRegister, ImmWord(dest)); - as_jr(ScratchRegister); + if (label->bound()) + addMixedJump(bo, ImmPtr((void*)label->offset()), MixedJumpPatch::PATCHABLE); + as_j(JOffImm26(0)); as_nop(); return CodeOffsetJump(bo.getOffset()); } diff --git a/js/src/jit/mips64/MacroAssembler-mips64.h b/js/src/jit/mips64/MacroAssembler-mips64.h index 6b98f1f2c..d4b850096 100644 --- a/js/src/jit/mips64/MacroAssembler-mips64.h +++ b/js/src/jit/mips64/MacroAssembler-mips64.h @@ -117,17 +117,17 @@ class MacroAssemblerMIPS64 : public MacroAssemblerMIPSShared void branchWithCode(InstImm code, Label* label, JumpKind jumpKind); // branches when done from within mips-specific code - void ma_b(Register lhs, ImmWord imm, Label* l, Condition c, JumpKind jumpKind = LongJump); - void ma_b(Register lhs, Address addr, Label* l, Condition c, JumpKind jumpKind = LongJump); - void ma_b(Address addr, Imm32 imm, Label* l, Condition c, JumpKind jumpKind = LongJump); - void ma_b(Address addr, ImmGCPtr imm, Label* l, Condition c, JumpKind jumpKind = LongJump); - void ma_b(Address addr, Register rhs, Label* l, Condition c, JumpKind jumpKind = LongJump) { + void ma_b(Register lhs, ImmWord imm, Label* l, Condition c, JumpKind jumpKind = MixedJump); + void ma_b(Register lhs, Address addr, Label* l, Condition c, JumpKind jumpKind = MixedJump); + void ma_b(Address addr, Imm32 imm, Label* l, Condition c, JumpKind jumpKind = MixedJump); + void ma_b(Address addr, ImmGCPtr imm, Label* l, Condition c, JumpKind jumpKind = MixedJump); + void ma_b(Address addr, Register rhs, Label* l, Condition c, JumpKind jumpKind = MixedJump) { MOZ_ASSERT(rhs != ScratchRegister); ma_load(ScratchRegister, addr, SizeDouble); ma_b(ScratchRegister, rhs, l, c, jumpKind); } - void ma_bal(Label* l, DelaySlotFill delaySlotFill = FillDelaySlot); + void ma_jal(Label* l); // fp instructions void ma_lid(FloatRegister dest, double value); -- cgit v1.2.3