diff options
Diffstat (limited to 'compiler/utils/mips64/assembler_mips64.cc')
-rw-r--r-- | compiler/utils/mips64/assembler_mips64.cc | 301 |
1 files changed, 266 insertions, 35 deletions
diff --git a/compiler/utils/mips64/assembler_mips64.cc b/compiler/utils/mips64/assembler_mips64.cc index 1a21df939e..84280b9c98 100644 --- a/compiler/utils/mips64/assembler_mips64.cc +++ b/compiler/utils/mips64/assembler_mips64.cc @@ -35,6 +35,7 @@ void Mips64Assembler::FinalizeCode() { for (auto& exception_block : exception_blocks_) { EmitExceptionPoll(&exception_block); } + EmitLiterals(); PromoteBranches(); } @@ -450,6 +451,21 @@ void Mips64Assembler::Lwu(GpuRegister rt, GpuRegister rs, uint16_t imm16) { EmitI(0x27, rs, rt, imm16); } +void Mips64Assembler::Lwpc(GpuRegister rs, uint32_t imm19) { + CHECK(IsUint<19>(imm19)) << imm19; + EmitI21(0x3B, rs, (0x01 << 19) | imm19); +} + +void Mips64Assembler::Lwupc(GpuRegister rs, uint32_t imm19) { + CHECK(IsUint<19>(imm19)) << imm19; + EmitI21(0x3B, rs, (0x02 << 19) | imm19); +} + +void Mips64Assembler::Ldpc(GpuRegister rs, uint32_t imm18) { + CHECK(IsUint<18>(imm18)) << imm18; + EmitI21(0x3B, rs, (0x06 << 18) | imm18); +} + void Mips64Assembler::Lui(GpuRegister rt, uint16_t imm16) { EmitI(0xf, static_cast<GpuRegister>(0), rt, imm16); } @@ -548,6 +564,10 @@ void Mips64Assembler::Bc(uint32_t imm26) { EmitI26(0x32, imm26); } +void Mips64Assembler::Balc(uint32_t imm26) { + EmitI26(0x3A, imm26); +} + void Mips64Assembler::Jic(GpuRegister rt, uint16_t imm16) { EmitI(0x36, static_cast<GpuRegister>(0), rt, imm16); } @@ -1064,19 +1084,37 @@ void Mips64Assembler::Branch::InitShortOrLong(Mips64Assembler::Branch::OffsetBit type_ = (offset_size <= branch_info_[short_type].offset_size) ? short_type : long_type; } -void Mips64Assembler::Branch::InitializeType(bool is_call) { +void Mips64Assembler::Branch::InitializeType(Type initial_type) { OffsetBits offset_size = GetOffsetSizeNeeded(location_, target_); - if (is_call) { - InitShortOrLong(offset_size, kCall, kLongCall); - } else if (condition_ == kUncond) { - InitShortOrLong(offset_size, kUncondBranch, kLongUncondBranch); - } else { - if (condition_ == kCondEQZ || condition_ == kCondNEZ) { - // Special case for beqzc/bnezc with longer offset than in other b<cond>c instructions. - type_ = (offset_size <= kOffset23) ? kCondBranch : kLongCondBranch; - } else { - InitShortOrLong(offset_size, kCondBranch, kLongCondBranch); - } + switch (initial_type) { + case kLabel: + case kLiteral: + case kLiteralUnsigned: + case kLiteralLong: + CHECK(!IsResolved()); + type_ = initial_type; + break; + case kCall: + InitShortOrLong(offset_size, kCall, kLongCall); + break; + case kCondBranch: + switch (condition_) { + case kUncond: + InitShortOrLong(offset_size, kUncondBranch, kLongUncondBranch); + break; + case kCondEQZ: + case kCondNEZ: + // Special case for beqzc/bnezc with longer offset than in other b<cond>c instructions. + type_ = (offset_size <= kOffset23) ? kCondBranch : kLongCondBranch; + break; + default: + InitShortOrLong(offset_size, kCondBranch, kLongCondBranch); + break; + } + break; + default: + LOG(FATAL) << "Unexpected branch type " << initial_type; + UNREACHABLE(); } old_type_ = type_; } @@ -1109,14 +1147,14 @@ bool Mips64Assembler::Branch::IsUncond(BranchCondition condition, } } -Mips64Assembler::Branch::Branch(uint32_t location, uint32_t target) +Mips64Assembler::Branch::Branch(uint32_t location, uint32_t target, bool is_call) : old_location_(location), location_(location), target_(target), lhs_reg_(ZERO), rhs_reg_(ZERO), condition_(kUncond) { - InitializeType(false); + InitializeType(is_call ? kCall : kCondBranch); } Mips64Assembler::Branch::Branch(uint32_t location, @@ -1164,19 +1202,18 @@ Mips64Assembler::Branch::Branch(uint32_t location, // Branch condition is always true, make the branch unconditional. condition_ = kUncond; } - InitializeType(false); + InitializeType(kCondBranch); } -Mips64Assembler::Branch::Branch(uint32_t location, uint32_t target, GpuRegister indirect_reg) +Mips64Assembler::Branch::Branch(uint32_t location, GpuRegister dest_reg, Type label_or_literal_type) : old_location_(location), location_(location), - target_(target), - lhs_reg_(indirect_reg), + target_(kUnresolved), + lhs_reg_(dest_reg), rhs_reg_(ZERO), condition_(kUncond) { - CHECK_NE(indirect_reg, ZERO); - CHECK_NE(indirect_reg, AT); - InitializeType(true); + CHECK_NE(dest_reg, ZERO); + InitializeType(label_or_literal_type); } Mips64Assembler::BranchCondition Mips64Assembler::Branch::OppositeCondition( @@ -1278,11 +1315,23 @@ bool Mips64Assembler::Branch::IsLong() const { case kUncondBranch: case kCondBranch: case kCall: + // Near label. + case kLabel: + // Near literals. + case kLiteral: + case kLiteralUnsigned: + case kLiteralLong: return false; // Long branches. case kLongUncondBranch: case kLongCondBranch: case kLongCall: + // Far label. + case kFarLabel: + // Far literals. + case kFarLiteral: + case kFarLiteralUnsigned: + case kFarLiteralLong: return true; } UNREACHABLE(); @@ -1351,6 +1400,20 @@ void Mips64Assembler::Branch::PromoteToLong() { case kCall: type_ = kLongCall; break; + // Near label. + case kLabel: + type_ = kFarLabel; + break; + // Near literals. + case kLiteral: + type_ = kFarLiteral; + break; + case kLiteralUnsigned: + type_ = kFarLiteralUnsigned; + break; + case kLiteralLong: + type_ = kFarLiteralLong; + break; default: // Note: 'type_' is already long. break; @@ -1397,7 +1460,15 @@ uint32_t Mips64Assembler::Branch::GetOffset() const { uint32_t ofs_mask = 0xFFFFFFFF >> (32 - GetOffsetSize()); // Calculate the byte distance between instructions and also account for // different PC-relative origins. - uint32_t offset = target_ - GetOffsetLocation() - branch_info_[type_].pc_org * sizeof(uint32_t); + uint32_t offset_location = GetOffsetLocation(); + if (type_ == kLiteralLong) { + // Special case for the ldpc instruction, whose address (PC) is rounded down to + // a multiple of 8 before adding the offset. + // Note, branch promotion has already taken care of aligning `target_` to an + // address that's a multiple of 8. + offset_location = RoundDown(offset_location, sizeof(uint64_t)); + } + uint32_t offset = target_ - offset_location - branch_info_[type_].pc_org * sizeof(uint32_t); // Prepare the offset for encoding into the instruction(s). offset = (offset & ofs_mask) >> branch_info_[type_].offset_shift; return offset; @@ -1444,7 +1515,7 @@ void Mips64Assembler::Bind(Mips64Label* label) { label->BindTo(bound_pc); } -uint32_t Mips64Assembler::GetLabelLocation(Mips64Label* label) const { +uint32_t Mips64Assembler::GetLabelLocation(const Mips64Label* label) const { CHECK(label->IsBound()); uint32_t target = label->Position(); if (label->prev_branch_id_plus_one_) { @@ -1500,7 +1571,7 @@ void Mips64Assembler::FinalizeLabeledBranch(Mips64Label* label) { void Mips64Assembler::Buncond(Mips64Label* label) { uint32_t target = label->IsBound() ? GetLabelLocation(label) : Branch::kUnresolved; - branches_.emplace_back(buffer_.Size(), target); + branches_.emplace_back(buffer_.Size(), target, /* is_call */ false); FinalizeLabeledBranch(label); } @@ -1517,12 +1588,87 @@ void Mips64Assembler::Bcond(Mips64Label* label, FinalizeLabeledBranch(label); } -void Mips64Assembler::Call(Mips64Label* label, GpuRegister indirect_reg) { +void Mips64Assembler::Call(Mips64Label* label) { uint32_t target = label->IsBound() ? GetLabelLocation(label) : Branch::kUnresolved; - branches_.emplace_back(buffer_.Size(), target, indirect_reg); + branches_.emplace_back(buffer_.Size(), target, /* is_call */ true); FinalizeLabeledBranch(label); } +void Mips64Assembler::LoadLabelAddress(GpuRegister dest_reg, Mips64Label* label) { + // Label address loads are treated as pseudo branches since they require very similar handling. + DCHECK(!label->IsBound()); + branches_.emplace_back(buffer_.Size(), dest_reg, Branch::kLabel); + FinalizeLabeledBranch(label); +} + +Literal* Mips64Assembler::NewLiteral(size_t size, const uint8_t* data) { + // We don't support byte and half-word literals. + if (size == 4u) { + literals_.emplace_back(size, data); + return &literals_.back(); + } else { + DCHECK_EQ(size, 8u); + long_literals_.emplace_back(size, data); + return &long_literals_.back(); + } +} + +void Mips64Assembler::LoadLiteral(GpuRegister dest_reg, + LoadOperandType load_type, + Literal* literal) { + // Literal loads are treated as pseudo branches since they require very similar handling. + Branch::Type literal_type; + switch (load_type) { + case kLoadWord: + DCHECK_EQ(literal->GetSize(), 4u); + literal_type = Branch::kLiteral; + break; + case kLoadUnsignedWord: + DCHECK_EQ(literal->GetSize(), 4u); + literal_type = Branch::kLiteralUnsigned; + break; + case kLoadDoubleword: + DCHECK_EQ(literal->GetSize(), 8u); + literal_type = Branch::kLiteralLong; + break; + default: + LOG(FATAL) << "Unexpected literal load type " << load_type; + UNREACHABLE(); + } + Mips64Label* label = literal->GetLabel(); + DCHECK(!label->IsBound()); + branches_.emplace_back(buffer_.Size(), dest_reg, literal_type); + FinalizeLabeledBranch(label); +} + +void Mips64Assembler::EmitLiterals() { + if (!literals_.empty()) { + for (Literal& literal : literals_) { + Mips64Label* label = literal.GetLabel(); + Bind(label); + AssemblerBuffer::EnsureCapacity ensured(&buffer_); + DCHECK_EQ(literal.GetSize(), 4u); + for (size_t i = 0, size = literal.GetSize(); i != size; ++i) { + buffer_.Emit<uint8_t>(literal.GetData()[i]); + } + } + } + if (!long_literals_.empty()) { + // Reserve 4 bytes for potential alignment. If after the branch promotion the 64-bit + // literals don't end up 8-byte-aligned, they will be moved down 4 bytes. + Emit(0); // NOP. + for (Literal& literal : long_literals_) { + Mips64Label* label = literal.GetLabel(); + Bind(label); + AssemblerBuffer::EnsureCapacity ensured(&buffer_); + DCHECK_EQ(literal.GetSize(), 8u); + for (size_t i = 0, size = literal.GetSize(); i != size; ++i) { + buffer_.Emit<uint8_t>(literal.GetData()[i]); + } + } + } +} + void Mips64Assembler::PromoteBranches() { // Promote short branches to long as necessary. bool changed; @@ -1561,6 +1707,35 @@ void Mips64Assembler::PromoteBranches() { end = branch.GetOldLocation(); } } + + // Align 64-bit literals by moving them down by 4 bytes if needed. + // This will reduce the PC-relative distance, which should be safe for both near and far literals. + if (!long_literals_.empty()) { + uint32_t first_literal_location = GetLabelLocation(long_literals_.front().GetLabel()); + size_t lit_size = long_literals_.size() * sizeof(uint64_t); + size_t buf_size = buffer_.Size(); + // 64-bit literals must be at the very end of the buffer. + CHECK_EQ(first_literal_location + lit_size, buf_size); + if (!IsAligned<sizeof(uint64_t)>(first_literal_location)) { + buffer_.Move(first_literal_location - sizeof(uint32_t), first_literal_location, lit_size); + // The 4 reserved bytes proved useless, reduce the buffer size. + buffer_.Resize(buf_size - sizeof(uint32_t)); + // Reduce target addresses in literal and address loads by 4 bytes in order for correct + // offsets from PC to be generated. + for (auto& branch : branches_) { + uint32_t target = branch.GetTarget(); + if (target >= first_literal_location) { + branch.Resolve(target - sizeof(uint32_t)); + } + } + // If after this we ever call GetLabelLocation() to get the location of a 64-bit literal, + // we need to adjust the location of the literal's label as well. + for (Literal& literal : long_literals_) { + // Bound label's position is negative, hence incrementing it instead of decrementing. + literal.GetLabel()->position_ += sizeof(uint32_t); + } + } + } } // Note: make sure branch_info_[] and EmitBranch() are kept synchronized. @@ -1569,11 +1744,23 @@ const Mips64Assembler::Branch::BranchInfo Mips64Assembler::Branch::branch_info_[ { 1, 0, 1, Mips64Assembler::Branch::kOffset28, 2 }, // kUncondBranch { 2, 0, 1, Mips64Assembler::Branch::kOffset18, 2 }, // kCondBranch // Exception: kOffset23 for beqzc/bnezc - { 2, 0, 0, Mips64Assembler::Branch::kOffset21, 2 }, // kCall + { 1, 0, 1, Mips64Assembler::Branch::kOffset28, 2 }, // kCall + // Near label. + { 1, 0, 0, Mips64Assembler::Branch::kOffset21, 2 }, // kLabel + // Near literals. + { 1, 0, 0, Mips64Assembler::Branch::kOffset21, 2 }, // kLiteral + { 1, 0, 0, Mips64Assembler::Branch::kOffset21, 2 }, // kLiteralUnsigned + { 1, 0, 0, Mips64Assembler::Branch::kOffset21, 3 }, // kLiteralLong // Long branches. { 2, 0, 0, Mips64Assembler::Branch::kOffset32, 0 }, // kLongUncondBranch { 3, 1, 0, Mips64Assembler::Branch::kOffset32, 0 }, // kLongCondBranch - { 3, 0, 0, Mips64Assembler::Branch::kOffset32, 0 }, // kLongCall + { 2, 0, 0, Mips64Assembler::Branch::kOffset32, 0 }, // kLongCall + // Far label. + { 2, 0, 0, Mips64Assembler::Branch::kOffset32, 0 }, // kFarLabel + // Far literals. + { 2, 0, 0, Mips64Assembler::Branch::kOffset32, 0 }, // kFarLiteral + { 2, 0, 0, Mips64Assembler::Branch::kOffset32, 0 }, // kFarLiteralUnsigned + { 2, 0, 0, Mips64Assembler::Branch::kOffset32, 0 }, // kFarLiteralLong }; // Note: make sure branch_info_[] and EmitBranch() are kept synchronized. @@ -1597,8 +1784,26 @@ void Mips64Assembler::EmitBranch(Mips64Assembler::Branch* branch) { break; case Branch::kCall: CHECK_EQ(overwrite_location_, branch->GetOffsetLocation()); + Balc(offset); + break; + + // Near label. + case Branch::kLabel: + CHECK_EQ(overwrite_location_, branch->GetOffsetLocation()); Addiupc(lhs, offset); - Jialc(lhs, 0); + break; + // Near literals. + case Branch::kLiteral: + CHECK_EQ(overwrite_location_, branch->GetOffsetLocation()); + Lwpc(lhs, offset); + break; + case Branch::kLiteralUnsigned: + CHECK_EQ(overwrite_location_, branch->GetOffsetLocation()); + Lwupc(lhs, offset); + break; + case Branch::kLiteralLong: + CHECK_EQ(overwrite_location_, branch->GetOffsetLocation()); + Ldpc(lhs, offset); break; // Long branches. @@ -1616,11 +1821,37 @@ void Mips64Assembler::EmitBranch(Mips64Assembler::Branch* branch) { Jic(AT, Low16Bits(offset)); break; case Branch::kLongCall: - offset += (offset & 0x8000) << 1; // Account for sign extension in daddiu. + offset += (offset & 0x8000) << 1; // Account for sign extension in jialc. + CHECK_EQ(overwrite_location_, branch->GetOffsetLocation()); + Auipc(AT, High16Bits(offset)); + Jialc(AT, Low16Bits(offset)); + break; + + // Far label. + case Branch::kFarLabel: + offset += (offset & 0x8000) << 1; // Account for sign extension in addiu. CHECK_EQ(overwrite_location_, branch->GetOffsetLocation()); - Auipc(lhs, High16Bits(offset)); - Daddiu(lhs, lhs, Low16Bits(offset)); - Jialc(lhs, 0); + Auipc(AT, High16Bits(offset)); + Addiu(lhs, AT, Low16Bits(offset)); + break; + // Far literals. + case Branch::kFarLiteral: + offset += (offset & 0x8000) << 1; // Account for sign extension in lw. + CHECK_EQ(overwrite_location_, branch->GetOffsetLocation()); + Auipc(AT, High16Bits(offset)); + Lw(lhs, AT, Low16Bits(offset)); + break; + case Branch::kFarLiteralUnsigned: + offset += (offset & 0x8000) << 1; // Account for sign extension in lwu. + CHECK_EQ(overwrite_location_, branch->GetOffsetLocation()); + Auipc(AT, High16Bits(offset)); + Lwu(lhs, AT, Low16Bits(offset)); + break; + case Branch::kFarLiteralLong: + offset += (offset & 0x8000) << 1; // Account for sign extension in ld. + CHECK_EQ(overwrite_location_, branch->GetOffsetLocation()); + Auipc(AT, High16Bits(offset)); + Ld(lhs, AT, Low16Bits(offset)); break; } CHECK_EQ(overwrite_location_, branch->GetEndLocation()); @@ -1631,8 +1862,8 @@ void Mips64Assembler::Bc(Mips64Label* label) { Buncond(label); } -void Mips64Assembler::Jialc(Mips64Label* label, GpuRegister indirect_reg) { - Call(label, indirect_reg); +void Mips64Assembler::Balc(Mips64Label* label) { + Call(label); } void Mips64Assembler::Bltc(GpuRegister rs, GpuRegister rt, Mips64Label* label) { |