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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
commit36d22d82aa202bb199967e9512281e9a53db42c9 (patch)
tree105e8c98ddea1c1e4784a60a5a6410fa416be2de /js/src/jit/arm64/vixl/Instructions-vixl.h
parentInitial commit. (diff)
downloadfirefox-esr-upstream.tar.xz
firefox-esr-upstream.zip
Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'js/src/jit/arm64/vixl/Instructions-vixl.h')
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+// Copyright 2015, ARM Limited
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// * Redistributions of source code must retain the above copyright notice,
+// this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above copyright notice,
+// this list of conditions and the following disclaimer in the documentation
+// and/or other materials provided with the distribution.
+// * Neither the name of ARM Limited nor the names of its contributors may be
+// used to endorse or promote products derived from this software without
+// specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS CONTRIBUTORS "AS IS" AND
+// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
+// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+// OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#ifndef VIXL_A64_INSTRUCTIONS_A64_H_
+#define VIXL_A64_INSTRUCTIONS_A64_H_
+
+#include "jit/arm64/vixl/Constants-vixl.h"
+#include "jit/arm64/vixl/Globals-vixl.h"
+#include "jit/arm64/vixl/Utils-vixl.h"
+
+namespace vixl {
+// ISA constants. --------------------------------------------------------------
+
+typedef uint32_t Instr;
+const unsigned kInstructionSize = 4;
+const unsigned kInstructionSizeLog2 = 2;
+const unsigned kLiteralEntrySize = 4;
+const unsigned kLiteralEntrySizeLog2 = 2;
+const unsigned kMaxLoadLiteralRange = 1 * MBytes;
+
+// This is the nominal page size (as used by the adrp instruction); the actual
+// size of the memory pages allocated by the kernel is likely to differ.
+const unsigned kPageSize = 4 * KBytes;
+const unsigned kPageSizeLog2 = 12;
+
+const unsigned kBRegSize = 8;
+const unsigned kBRegSizeLog2 = 3;
+const unsigned kBRegSizeInBytes = kBRegSize / 8;
+const unsigned kBRegSizeInBytesLog2 = kBRegSizeLog2 - 3;
+const unsigned kHRegSize = 16;
+const unsigned kHRegSizeLog2 = 4;
+const unsigned kHRegSizeInBytes = kHRegSize / 8;
+const unsigned kHRegSizeInBytesLog2 = kHRegSizeLog2 - 3;
+const unsigned kWRegSize = 32;
+const unsigned kWRegSizeLog2 = 5;
+const unsigned kWRegSizeInBytes = kWRegSize / 8;
+const unsigned kWRegSizeInBytesLog2 = kWRegSizeLog2 - 3;
+const unsigned kXRegSize = 64;
+const unsigned kXRegSizeLog2 = 6;
+const unsigned kXRegSizeInBytes = kXRegSize / 8;
+const unsigned kXRegSizeInBytesLog2 = kXRegSizeLog2 - 3;
+const unsigned kSRegSize = 32;
+const unsigned kSRegSizeLog2 = 5;
+const unsigned kSRegSizeInBytes = kSRegSize / 8;
+const unsigned kSRegSizeInBytesLog2 = kSRegSizeLog2 - 3;
+const unsigned kDRegSize = 64;
+const unsigned kDRegSizeLog2 = 6;
+const unsigned kDRegSizeInBytes = kDRegSize / 8;
+const unsigned kDRegSizeInBytesLog2 = kDRegSizeLog2 - 3;
+const unsigned kQRegSize = 128;
+const unsigned kQRegSizeLog2 = 7;
+const unsigned kQRegSizeInBytes = kQRegSize / 8;
+const unsigned kQRegSizeInBytesLog2 = kQRegSizeLog2 - 3;
+const uint64_t kWRegMask = UINT64_C(0xffffffff);
+const uint64_t kXRegMask = UINT64_C(0xffffffffffffffff);
+const uint64_t kSRegMask = UINT64_C(0xffffffff);
+const uint64_t kDRegMask = UINT64_C(0xffffffffffffffff);
+const uint64_t kSSignMask = UINT64_C(0x80000000);
+const uint64_t kDSignMask = UINT64_C(0x8000000000000000);
+const uint64_t kWSignMask = UINT64_C(0x80000000);
+const uint64_t kXSignMask = UINT64_C(0x8000000000000000);
+const uint64_t kByteMask = UINT64_C(0xff);
+const uint64_t kHalfWordMask = UINT64_C(0xffff);
+const uint64_t kWordMask = UINT64_C(0xffffffff);
+const uint64_t kXMaxUInt = UINT64_C(0xffffffffffffffff);
+const uint64_t kXMaxExactUInt = UINT64_C(0xfffffffffffff800);
+const uint64_t kWMaxUInt = UINT64_C(0xffffffff);
+const int64_t kXMaxInt = INT64_C(0x7fffffffffffffff);
+const int64_t kXMaxExactInt = UINT64_C(0x7ffffffffffffc00);
+const int64_t kXMinInt = INT64_C(0x8000000000000000);
+const int32_t kWMaxInt = INT32_C(0x7fffffff);
+const int32_t kWMinInt = INT32_C(0x80000000);
+const unsigned kLinkRegCode = 30;
+const unsigned kZeroRegCode = 31;
+const unsigned kSPRegInternalCode = 63;
+const unsigned kRegCodeMask = 0x1f;
+
+const unsigned kAddressTagOffset = 56;
+const unsigned kAddressTagWidth = 8;
+const uint64_t kAddressTagMask =
+ ((UINT64_C(1) << kAddressTagWidth) - 1) << kAddressTagOffset;
+VIXL_STATIC_ASSERT(kAddressTagMask == UINT64_C(0xff00000000000000));
+
+static inline unsigned CalcLSDataSize(LoadStoreOp op) {
+ VIXL_ASSERT((LSSize_offset + LSSize_width) == (kInstructionSize * 8));
+ unsigned size = static_cast<Instr>(op) >> LSSize_offset;
+ if ((op & LSVector_mask) != 0) {
+ // Vector register memory operations encode the access size in the "size"
+ // and "opc" fields.
+ if ((size == 0) && ((op & LSOpc_mask) >> LSOpc_offset) >= 2) {
+ size = kQRegSizeInBytesLog2;
+ }
+ }
+ return size;
+}
+
+unsigned CalcLSPairDataSize(LoadStorePairOp op);
+
+enum ImmBranchType {
+ UnknownBranchType = 0,
+ CondBranchType = 1,
+ UncondBranchType = 2,
+ CompareBranchType = 3,
+ TestBranchType = 4
+};
+
+// The classes of immediate branch ranges, in order of increasing range.
+// Note that CondBranchType and CompareBranchType have the same range.
+enum ImmBranchRangeType {
+ TestBranchRangeType, // tbz/tbnz: imm14 = +/- 32KB.
+ CondBranchRangeType, // b.cond/cbz/cbnz: imm19 = +/- 1MB.
+ UncondBranchRangeType, // b/bl: imm26 = +/- 128MB.
+ UnknownBranchRangeType,
+
+ // Number of 'short-range' branch range types.
+ // We don't consider unconditional branches 'short-range'.
+ NumShortBranchRangeTypes = UncondBranchRangeType
+};
+
+enum AddrMode {
+ Offset,
+ PreIndex,
+ PostIndex
+};
+
+enum Reg31Mode {
+ Reg31IsStackPointer,
+ Reg31IsZeroRegister
+};
+
+// Instructions. ---------------------------------------------------------------
+
+class Instruction {
+ public:
+ Instr InstructionBits() const {
+ return *(reinterpret_cast<const Instr*>(this));
+ }
+
+ void SetInstructionBits(Instr new_instr) {
+ *(reinterpret_cast<Instr*>(this)) = new_instr;
+ }
+
+ int Bit(int pos) const {
+ return (InstructionBits() >> pos) & 1;
+ }
+
+ uint32_t Bits(int msb, int lsb) const {
+ return ExtractUnsignedBitfield32(msb, lsb, InstructionBits());
+ }
+
+ int32_t SignedBits(int msb, int lsb) const {
+ int32_t bits = *(reinterpret_cast<const int32_t*>(this));
+ return ExtractSignedBitfield32(msb, lsb, bits);
+ }
+
+ Instr Mask(uint32_t mask) const {
+ return InstructionBits() & mask;
+ }
+
+ #define DEFINE_GETTER(Name, HighBit, LowBit, Func) \
+ int32_t Name() const { return Func(HighBit, LowBit); }
+ INSTRUCTION_FIELDS_LIST(DEFINE_GETTER)
+ #undef DEFINE_GETTER
+
+ #define DEFINE_SETTER(Name, HighBit, LowBit, Func) \
+ inline void Set##Name(unsigned n) { SetBits32(HighBit, LowBit, n); }
+ INSTRUCTION_FIELDS_LIST(DEFINE_SETTER)
+ #undef DEFINE_SETTER
+
+ // ImmPCRel is a compound field (not present in INSTRUCTION_FIELDS_LIST),
+ // formed from ImmPCRelLo and ImmPCRelHi.
+ int ImmPCRel() const {
+ int offset =
+ static_cast<int>((ImmPCRelHi() << ImmPCRelLo_width) | ImmPCRelLo());
+ int width = ImmPCRelLo_width + ImmPCRelHi_width;
+ return ExtractSignedBitfield32(width - 1, 0, offset);
+ }
+
+ uint64_t ImmLogical() const;
+ unsigned ImmNEONabcdefgh() const;
+ float ImmFP32() const;
+ double ImmFP64() const;
+ float ImmNEONFP32() const;
+ double ImmNEONFP64() const;
+
+ unsigned SizeLS() const {
+ return CalcLSDataSize(static_cast<LoadStoreOp>(Mask(LoadStoreMask)));
+ }
+
+ unsigned SizeLSPair() const {
+ return CalcLSPairDataSize(
+ static_cast<LoadStorePairOp>(Mask(LoadStorePairMask)));
+ }
+
+ int NEONLSIndex(int access_size_shift) const {
+ int64_t q = NEONQ();
+ int64_t s = NEONS();
+ int64_t size = NEONLSSize();
+ int64_t index = (q << 3) | (s << 2) | size;
+ return static_cast<int>(index >> access_size_shift);
+ }
+
+ // Helpers.
+ bool IsCondBranchImm() const {
+ return Mask(ConditionalBranchFMask) == ConditionalBranchFixed;
+ }
+
+ bool IsUncondBranchImm() const {
+ return Mask(UnconditionalBranchFMask) == UnconditionalBranchFixed;
+ }
+
+ bool IsCompareBranch() const {
+ return Mask(CompareBranchFMask) == CompareBranchFixed;
+ }
+
+ bool IsTestBranch() const {
+ return Mask(TestBranchFMask) == TestBranchFixed;
+ }
+
+ bool IsImmBranch() const {
+ return BranchType() != UnknownBranchType;
+ }
+
+ bool IsPCRelAddressing() const {
+ return Mask(PCRelAddressingFMask) == PCRelAddressingFixed;
+ }
+
+ bool IsLogicalImmediate() const {
+ return Mask(LogicalImmediateFMask) == LogicalImmediateFixed;
+ }
+
+ bool IsAddSubImmediate() const {
+ return Mask(AddSubImmediateFMask) == AddSubImmediateFixed;
+ }
+
+ bool IsAddSubExtended() const {
+ return Mask(AddSubExtendedFMask) == AddSubExtendedFixed;
+ }
+
+ bool IsLoadOrStore() const {
+ return Mask(LoadStoreAnyFMask) == LoadStoreAnyFixed;
+ }
+
+ bool IsLoad() const;
+ bool IsStore() const;
+
+ bool IsLoadLiteral() const {
+ // This includes PRFM_lit.
+ return Mask(LoadLiteralFMask) == LoadLiteralFixed;
+ }
+
+ bool IsMovn() const {
+ return (Mask(MoveWideImmediateMask) == MOVN_x) ||
+ (Mask(MoveWideImmediateMask) == MOVN_w);
+ }
+
+ // Mozilla modifications.
+ bool IsUncondB() const;
+ bool IsCondB() const;
+ bool IsBL() const;
+ bool IsBR() const;
+ bool IsBLR() const;
+ bool IsTBZ() const;
+ bool IsTBNZ() const;
+ bool IsCBZ() const;
+ bool IsCBNZ() const;
+ bool IsLDR() const;
+ bool IsNOP() const;
+ bool IsCSDB() const;
+ bool IsADR() const;
+ bool IsADRP() const;
+ bool IsMovz() const;
+ bool IsMovk() const;
+ bool IsBranchLinkImm() const;
+ bool IsTargetReachable(const Instruction* target) const;
+ ptrdiff_t ImmPCRawOffset() const;
+ void SetImmPCRawOffset(ptrdiff_t offset);
+ void SetBits32(int msb, int lsb, unsigned value);
+
+ // Is this a stack pointer synchronization instruction as inserted by
+ // MacroAssembler::syncStackPtr()?
+ bool IsStackPtrSync() const;
+
+ static int ImmBranchRangeBitwidth(ImmBranchType branch_type);
+ static int32_t ImmBranchForwardRange(ImmBranchType branch_type);
+
+ // Check if offset can be encoded as a RAW offset in a branch_type
+ // instruction. The offset must be encodeable directly as the immediate field
+ // in the instruction, it is not scaled by kInstructionSize first.
+ static bool IsValidImmPCOffset(ImmBranchType branch_type, int64_t offset);
+
+ // Get the range type corresponding to a branch type.
+ static ImmBranchRangeType ImmBranchTypeToRange(ImmBranchType);
+
+ // Get the maximum realizable forward PC offset (in bytes) for an immediate
+ // branch of the given range type.
+ // This is the largest positive multiple of kInstructionSize, offset, such
+ // that:
+ //
+ // IsValidImmPCOffset(xxx, offset / kInstructionSize)
+ //
+ // returns true for the same branch type.
+ static int32_t ImmBranchMaxForwardOffset(ImmBranchRangeType range_type);
+
+ // Get the minimuum realizable backward PC offset (in bytes) for an immediate
+ // branch of the given range type.
+ // This is the smallest (i.e., largest in magnitude) negative multiple of
+ // kInstructionSize, offset, such that:
+ //
+ // IsValidImmPCOffset(xxx, offset / kInstructionSize)
+ //
+ // returns true for the same branch type.
+ static int32_t ImmBranchMinBackwardOffset(ImmBranchRangeType range_type);
+
+ // Indicate whether Rd can be the stack pointer or the zero register. This
+ // does not check that the instruction actually has an Rd field.
+ Reg31Mode RdMode() const {
+ // The following instructions use sp or wsp as Rd:
+ // Add/sub (immediate) when not setting the flags.
+ // Add/sub (extended) when not setting the flags.
+ // Logical (immediate) when not setting the flags.
+ // Otherwise, r31 is the zero register.
+ if (IsAddSubImmediate() || IsAddSubExtended()) {
+ if (Mask(AddSubSetFlagsBit)) {
+ return Reg31IsZeroRegister;
+ } else {
+ return Reg31IsStackPointer;
+ }
+ }
+ if (IsLogicalImmediate()) {
+ // Of the logical (immediate) instructions, only ANDS (and its aliases)
+ // can set the flags. The others can all write into sp.
+ // Note that some logical operations are not available to
+ // immediate-operand instructions, so we have to combine two masks here.
+ if (Mask(LogicalImmediateMask & LogicalOpMask) == ANDS) {
+ return Reg31IsZeroRegister;
+ } else {
+ return Reg31IsStackPointer;
+ }
+ }
+ return Reg31IsZeroRegister;
+ }
+
+ // Indicate whether Rn can be the stack pointer or the zero register. This
+ // does not check that the instruction actually has an Rn field.
+ Reg31Mode RnMode() const {
+ // The following instructions use sp or wsp as Rn:
+ // All loads and stores.
+ // Add/sub (immediate).
+ // Add/sub (extended).
+ // Otherwise, r31 is the zero register.
+ if (IsLoadOrStore() || IsAddSubImmediate() || IsAddSubExtended()) {
+ return Reg31IsStackPointer;
+ }
+ return Reg31IsZeroRegister;
+ }
+
+ ImmBranchType BranchType() const {
+ if (IsCondBranchImm()) {
+ return CondBranchType;
+ } else if (IsUncondBranchImm()) {
+ return UncondBranchType;
+ } else if (IsCompareBranch()) {
+ return CompareBranchType;
+ } else if (IsTestBranch()) {
+ return TestBranchType;
+ } else {
+ return UnknownBranchType;
+ }
+ }
+
+ // Find the target of this instruction. 'this' may be a branch or a
+ // PC-relative addressing instruction.
+ const Instruction* ImmPCOffsetTarget() const;
+
+ // Patch a PC-relative offset to refer to 'target'. 'this' may be a branch or
+ // a PC-relative addressing instruction.
+ void SetImmPCOffsetTarget(const Instruction* target);
+ // Patch a literal load instruction to load from 'source'.
+ void SetImmLLiteral(const Instruction* source);
+
+ // The range of a load literal instruction, expressed as 'instr +- range'.
+ // The range is actually the 'positive' range; the branch instruction can
+ // target [instr - range - kInstructionSize, instr + range].
+ static const int kLoadLiteralImmBitwidth = 19;
+ static const int kLoadLiteralRange =
+ (1 << kLoadLiteralImmBitwidth) / 2 - kInstructionSize;
+
+ // Calculate the address of a literal referred to by a load-literal
+ // instruction, and return it as the specified type.
+ //
+ // The literal itself is safely mutable only if the backing buffer is safely
+ // mutable.
+ template <typename T>
+ T LiteralAddress() const {
+ uint64_t base_raw = reinterpret_cast<uint64_t>(this);
+ int64_t offset = ImmLLiteral() << kLiteralEntrySizeLog2;
+ uint64_t address_raw = base_raw + offset;
+
+ // Cast the address using a C-style cast. A reinterpret_cast would be
+ // appropriate, but it can't cast one integral type to another.
+ T address = (T)(address_raw);
+
+ // Assert that the address can be represented by the specified type.
+ VIXL_ASSERT((uint64_t)(address) == address_raw);
+
+ return address;
+ }
+
+ uint32_t Literal32() const {
+ uint32_t literal;
+ memcpy(&literal, LiteralAddress<const void*>(), sizeof(literal));
+ return literal;
+ }
+
+ uint64_t Literal64() const {
+ uint64_t literal;
+ memcpy(&literal, LiteralAddress<const void*>(), sizeof(literal));
+ return literal;
+ }
+
+ void SetLiteral64(uint64_t literal) const {
+ memcpy(LiteralAddress<void*>(), &literal, sizeof(literal));
+ }
+
+ float LiteralFP32() const {
+ return RawbitsToFloat(Literal32());
+ }
+
+ double LiteralFP64() const {
+ return RawbitsToDouble(Literal64());
+ }
+
+ const Instruction* NextInstruction() const {
+ return this + kInstructionSize;
+ }
+
+ // Skip any constant pools with artificial guards at this point.
+ // Return either |this| or the first instruction after the pool.
+ const Instruction* skipPool() const;
+
+ const Instruction* InstructionAtOffset(int64_t offset) const {
+ VIXL_ASSERT(IsWordAligned(this + offset));
+ return this + offset;
+ }
+
+ template<typename T> static Instruction* Cast(T src) {
+ return reinterpret_cast<Instruction*>(src);
+ }
+
+ template<typename T> static const Instruction* CastConst(T src) {
+ return reinterpret_cast<const Instruction*>(src);
+ }
+
+ private:
+ int ImmBranch() const;
+
+ static float Imm8ToFP32(uint32_t imm8);
+ static double Imm8ToFP64(uint32_t imm8);
+
+ void SetPCRelImmTarget(const Instruction* target);
+ void SetBranchImmTarget(const Instruction* target);
+};
+
+
+// Functions for handling NEON vector format information.
+enum VectorFormat {
+ kFormatUndefined = 0xffffffff,
+ kFormat8B = NEON_8B,
+ kFormat16B = NEON_16B,
+ kFormat4H = NEON_4H,
+ kFormat8H = NEON_8H,
+ kFormat2S = NEON_2S,
+ kFormat4S = NEON_4S,
+ kFormat1D = NEON_1D,
+ kFormat2D = NEON_2D,
+
+ // Scalar formats. We add the scalar bit to distinguish between scalar and
+ // vector enumerations; the bit is always set in the encoding of scalar ops
+ // and always clear for vector ops. Although kFormatD and kFormat1D appear
+ // to be the same, their meaning is subtly different. The first is a scalar
+ // operation, the second a vector operation that only affects one lane.
+ kFormatB = NEON_B | NEONScalar,
+ kFormatH = NEON_H | NEONScalar,
+ kFormatS = NEON_S | NEONScalar,
+ kFormatD = NEON_D | NEONScalar
+};
+
+VectorFormat VectorFormatHalfWidth(const VectorFormat vform);
+VectorFormat VectorFormatDoubleWidth(const VectorFormat vform);
+VectorFormat VectorFormatDoubleLanes(const VectorFormat vform);
+VectorFormat VectorFormatHalfLanes(const VectorFormat vform);
+VectorFormat ScalarFormatFromLaneSize(int lanesize);
+VectorFormat VectorFormatHalfWidthDoubleLanes(const VectorFormat vform);
+VectorFormat VectorFormatFillQ(const VectorFormat vform);
+unsigned RegisterSizeInBitsFromFormat(VectorFormat vform);
+unsigned RegisterSizeInBytesFromFormat(VectorFormat vform);
+// TODO: Make the return types of these functions consistent.
+unsigned LaneSizeInBitsFromFormat(VectorFormat vform);
+int LaneSizeInBytesFromFormat(VectorFormat vform);
+int LaneSizeInBytesLog2FromFormat(VectorFormat vform);
+int LaneCountFromFormat(VectorFormat vform);
+int MaxLaneCountFromFormat(VectorFormat vform);
+bool IsVectorFormat(VectorFormat vform);
+int64_t MaxIntFromFormat(VectorFormat vform);
+int64_t MinIntFromFormat(VectorFormat vform);
+uint64_t MaxUintFromFormat(VectorFormat vform);
+
+
+enum NEONFormat {
+ NF_UNDEF = 0,
+ NF_8B = 1,
+ NF_16B = 2,
+ NF_4H = 3,
+ NF_8H = 4,
+ NF_2S = 5,
+ NF_4S = 6,
+ NF_1D = 7,
+ NF_2D = 8,
+ NF_B = 9,
+ NF_H = 10,
+ NF_S = 11,
+ NF_D = 12
+};
+
+static const unsigned kNEONFormatMaxBits = 6;
+
+struct NEONFormatMap {
+ // The bit positions in the instruction to consider.
+ uint8_t bits[kNEONFormatMaxBits];
+
+ // Mapping from concatenated bits to format.
+ NEONFormat map[1 << kNEONFormatMaxBits];
+};
+
+class NEONFormatDecoder {
+ public:
+ enum SubstitutionMode {
+ kPlaceholder,
+ kFormat
+ };
+
+ // Construct a format decoder with increasingly specific format maps for each
+ // subsitution. If no format map is specified, the default is the integer
+ // format map.
+ explicit NEONFormatDecoder(const Instruction* instr) {
+ instrbits_ = instr->InstructionBits();
+ SetFormatMaps(IntegerFormatMap());
+ }
+ NEONFormatDecoder(const Instruction* instr,
+ const NEONFormatMap* format) {
+ instrbits_ = instr->InstructionBits();
+ SetFormatMaps(format);
+ }
+ NEONFormatDecoder(const Instruction* instr,
+ const NEONFormatMap* format0,
+ const NEONFormatMap* format1) {
+ instrbits_ = instr->InstructionBits();
+ SetFormatMaps(format0, format1);
+ }
+ NEONFormatDecoder(const Instruction* instr,
+ const NEONFormatMap* format0,
+ const NEONFormatMap* format1,
+ const NEONFormatMap* format2) {
+ instrbits_ = instr->InstructionBits();
+ SetFormatMaps(format0, format1, format2);
+ }
+
+ // Set the format mapping for all or individual substitutions.
+ void SetFormatMaps(const NEONFormatMap* format0,
+ const NEONFormatMap* format1 = NULL,
+ const NEONFormatMap* format2 = NULL) {
+ VIXL_ASSERT(format0 != NULL);
+ formats_[0] = format0;
+ formats_[1] = (format1 == NULL) ? formats_[0] : format1;
+ formats_[2] = (format2 == NULL) ? formats_[1] : format2;
+ }
+ void SetFormatMap(unsigned index, const NEONFormatMap* format) {
+ VIXL_ASSERT(index <= (sizeof(formats_) / sizeof(formats_[0])));
+ VIXL_ASSERT(format != NULL);
+ formats_[index] = format;
+ }
+
+ // Substitute %s in the input string with the placeholder string for each
+ // register, ie. "'B", "'H", etc.
+ const char* SubstitutePlaceholders(const char* string) {
+ return Substitute(string, kPlaceholder, kPlaceholder, kPlaceholder);
+ }
+
+ // Substitute %s in the input string with a new string based on the
+ // substitution mode.
+ const char* Substitute(const char* string,
+ SubstitutionMode mode0 = kFormat,
+ SubstitutionMode mode1 = kFormat,
+ SubstitutionMode mode2 = kFormat) {
+ snprintf(form_buffer_, sizeof(form_buffer_), string,
+ GetSubstitute(0, mode0),
+ GetSubstitute(1, mode1),
+ GetSubstitute(2, mode2));
+ return form_buffer_;
+ }
+
+ // Append a "2" to a mnemonic string based of the state of the Q bit.
+ const char* Mnemonic(const char* mnemonic) {
+ if ((instrbits_ & NEON_Q) != 0) {
+ snprintf(mne_buffer_, sizeof(mne_buffer_), "%s2", mnemonic);
+ return mne_buffer_;
+ }
+ return mnemonic;
+ }
+
+ VectorFormat GetVectorFormat(int format_index = 0) {
+ return GetVectorFormat(formats_[format_index]);
+ }
+
+ VectorFormat GetVectorFormat(const NEONFormatMap* format_map) {
+ static const VectorFormat vform[] = {
+ kFormatUndefined,
+ kFormat8B, kFormat16B, kFormat4H, kFormat8H,
+ kFormat2S, kFormat4S, kFormat1D, kFormat2D,
+ kFormatB, kFormatH, kFormatS, kFormatD
+ };
+ VIXL_ASSERT(GetNEONFormat(format_map) < (sizeof(vform) / sizeof(vform[0])));
+ return vform[GetNEONFormat(format_map)];
+ }
+
+ // Built in mappings for common cases.
+
+ // The integer format map uses three bits (Q, size<1:0>) to encode the
+ // "standard" set of NEON integer vector formats.
+ static const NEONFormatMap* IntegerFormatMap() {
+ static const NEONFormatMap map = {
+ {23, 22, 30},
+ {NF_8B, NF_16B, NF_4H, NF_8H, NF_2S, NF_4S, NF_UNDEF, NF_2D}
+ };
+ return &map;
+ }
+
+ // The long integer format map uses two bits (size<1:0>) to encode the
+ // long set of NEON integer vector formats. These are used in narrow, wide
+ // and long operations.
+ static const NEONFormatMap* LongIntegerFormatMap() {
+ static const NEONFormatMap map = {
+ {23, 22}, {NF_8H, NF_4S, NF_2D}
+ };
+ return &map;
+ }
+
+ // The FP format map uses two bits (Q, size<0>) to encode the NEON FP vector
+ // formats: NF_2S, NF_4S, NF_2D.
+ static const NEONFormatMap* FPFormatMap() {
+ // The FP format map assumes two bits (Q, size<0>) are used to encode the
+ // NEON FP vector formats: NF_2S, NF_4S, NF_2D.
+ static const NEONFormatMap map = {
+ {22, 30}, {NF_2S, NF_4S, NF_UNDEF, NF_2D}
+ };
+ return &map;
+ }
+
+ // The load/store format map uses three bits (Q, 11, 10) to encode the
+ // set of NEON vector formats.
+ static const NEONFormatMap* LoadStoreFormatMap() {
+ static const NEONFormatMap map = {
+ {11, 10, 30},
+ {NF_8B, NF_16B, NF_4H, NF_8H, NF_2S, NF_4S, NF_1D, NF_2D}
+ };
+ return &map;
+ }
+
+ // The logical format map uses one bit (Q) to encode the NEON vector format:
+ // NF_8B, NF_16B.
+ static const NEONFormatMap* LogicalFormatMap() {
+ static const NEONFormatMap map = {
+ {30}, {NF_8B, NF_16B}
+ };
+ return &map;
+ }
+
+ // The triangular format map uses between two and five bits to encode the NEON
+ // vector format:
+ // xxx10->8B, xxx11->16B, xx100->4H, xx101->8H
+ // x1000->2S, x1001->4S, 10001->2D, all others undefined.
+ static const NEONFormatMap* TriangularFormatMap() {
+ static const NEONFormatMap map = {
+ {19, 18, 17, 16, 30},
+ {NF_UNDEF, NF_UNDEF, NF_8B, NF_16B, NF_4H, NF_8H, NF_8B, NF_16B, NF_2S,
+ NF_4S, NF_8B, NF_16B, NF_4H, NF_8H, NF_8B, NF_16B, NF_UNDEF, NF_2D,
+ NF_8B, NF_16B, NF_4H, NF_8H, NF_8B, NF_16B, NF_2S, NF_4S, NF_8B, NF_16B,
+ NF_4H, NF_8H, NF_8B, NF_16B}
+ };
+ return &map;
+ }
+
+ // The scalar format map uses two bits (size<1:0>) to encode the NEON scalar
+ // formats: NF_B, NF_H, NF_S, NF_D.
+ static const NEONFormatMap* ScalarFormatMap() {
+ static const NEONFormatMap map = {
+ {23, 22}, {NF_B, NF_H, NF_S, NF_D}
+ };
+ return &map;
+ }
+
+ // The long scalar format map uses two bits (size<1:0>) to encode the longer
+ // NEON scalar formats: NF_H, NF_S, NF_D.
+ static const NEONFormatMap* LongScalarFormatMap() {
+ static const NEONFormatMap map = {
+ {23, 22}, {NF_H, NF_S, NF_D}
+ };
+ return &map;
+ }
+
+ // The FP scalar format map assumes one bit (size<0>) is used to encode the
+ // NEON FP scalar formats: NF_S, NF_D.
+ static const NEONFormatMap* FPScalarFormatMap() {
+ static const NEONFormatMap map = {
+ {22}, {NF_S, NF_D}
+ };
+ return &map;
+ }
+
+ // The triangular scalar format map uses between one and four bits to encode
+ // the NEON FP scalar formats:
+ // xxx1->B, xx10->H, x100->S, 1000->D, all others undefined.
+ static const NEONFormatMap* TriangularScalarFormatMap() {
+ static const NEONFormatMap map = {
+ {19, 18, 17, 16},
+ {NF_UNDEF, NF_B, NF_H, NF_B, NF_S, NF_B, NF_H, NF_B,
+ NF_D, NF_B, NF_H, NF_B, NF_S, NF_B, NF_H, NF_B}
+ };
+ return &map;
+ }
+
+ private:
+ // Get a pointer to a string that represents the format or placeholder for
+ // the specified substitution index, based on the format map and instruction.
+ const char* GetSubstitute(int index, SubstitutionMode mode) {
+ if (mode == kFormat) {
+ return NEONFormatAsString(GetNEONFormat(formats_[index]));
+ }
+ VIXL_ASSERT(mode == kPlaceholder);
+ return NEONFormatAsPlaceholder(GetNEONFormat(formats_[index]));
+ }
+
+ // Get the NEONFormat enumerated value for bits obtained from the
+ // instruction based on the specified format mapping.
+ NEONFormat GetNEONFormat(const NEONFormatMap* format_map) {
+ return format_map->map[PickBits(format_map->bits)];
+ }
+
+ // Convert a NEONFormat into a string.
+ static const char* NEONFormatAsString(NEONFormat format) {
+ static const char* formats[] = {
+ "undefined",
+ "8b", "16b", "4h", "8h", "2s", "4s", "1d", "2d",
+ "b", "h", "s", "d"
+ };
+ VIXL_ASSERT(format < (sizeof(formats) / sizeof(formats[0])));
+ return formats[format];
+ }
+
+ // Convert a NEONFormat into a register placeholder string.
+ static const char* NEONFormatAsPlaceholder(NEONFormat format) {
+ VIXL_ASSERT((format == NF_B) || (format == NF_H) ||
+ (format == NF_S) || (format == NF_D) ||
+ (format == NF_UNDEF));
+ static const char* formats[] = {
+ "undefined",
+ "undefined", "undefined", "undefined", "undefined",
+ "undefined", "undefined", "undefined", "undefined",
+ "'B", "'H", "'S", "'D"
+ };
+ return formats[format];
+ }
+
+ // Select bits from instrbits_ defined by the bits array, concatenate them,
+ // and return the value.
+ uint8_t PickBits(const uint8_t bits[]) {
+ uint8_t result = 0;
+ for (unsigned b = 0; b < kNEONFormatMaxBits; b++) {
+ if (bits[b] == 0) break;
+ result <<= 1;
+ result |= ((instrbits_ & (1 << bits[b])) == 0) ? 0 : 1;
+ }
+ return result;
+ }
+
+ Instr instrbits_;
+ const NEONFormatMap* formats_[3];
+ char form_buffer_[64];
+ char mne_buffer_[16];
+};
+} // namespace vixl
+
+#endif // VIXL_A64_INSTRUCTIONS_A64_H_