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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: set ts=8 sts=2 et sw=2 tw=80:
+ */
+// Copyright 2011 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef jit_arm_disasm_Constants_arm_h
+#define jit_arm_disasm_Constants_arm_h
+
+#ifdef JS_DISASM_ARM
+
+# include "mozilla/Assertions.h"
+# include "mozilla/Types.h"
+
+# include <string.h>
+
+namespace js {
+namespace jit {
+namespace disasm {
+
+// Constant pool marker.
+// Use UDF, the permanently undefined instruction.
+const int kConstantPoolMarkerMask = 0xfff000f0;
+const int kConstantPoolMarker = 0xe7f000f0;
+const int kConstantPoolLengthMaxMask = 0xffff;
+
+inline int EncodeConstantPoolLength(int length) {
+ MOZ_ASSERT((length & kConstantPoolLengthMaxMask) == length);
+ return ((length & 0xfff0) << 4) | (length & 0xf);
+}
+
+inline int DecodeConstantPoolLength(int instr) {
+ MOZ_ASSERT((instr & kConstantPoolMarkerMask) == kConstantPoolMarker);
+ return ((instr >> 4) & 0xfff0) | (instr & 0xf);
+}
+
+// Used in code age prologue - ldr(pc, MemOperand(pc, -4))
+const int kCodeAgeJumpInstruction = 0xe51ff004;
+
+// Number of registers in normal ARM mode.
+const int kNumRegisters = 16;
+
+// VFP support.
+const int kNumVFPSingleRegisters = 32;
+const int kNumVFPDoubleRegisters = 32;
+const int kNumVFPRegisters = kNumVFPSingleRegisters + kNumVFPDoubleRegisters;
+
+// PC is register 15.
+const int kPCRegister = 15;
+const int kNoRegister = -1;
+
+// -----------------------------------------------------------------------------
+// Conditions.
+
+// Defines constants and accessor classes to assemble, disassemble and
+// simulate ARM instructions.
+//
+// Section references in the code refer to the "ARM Architecture Reference
+// Manual" from July 2005 (available at http://www.arm.com/miscPDFs/14128.pdf)
+//
+// Constants for specific fields are defined in their respective named enums.
+// General constants are in an anonymous enum in class Instr.
+
+// Values for the condition field as defined in section A3.2
+enum Condition {
+ kNoCondition = -1,
+
+ eq = 0 << 28, // Z set Equal.
+ ne = 1 << 28, // Z clear Not equal.
+ cs = 2 << 28, // C set Unsigned higher or same.
+ cc = 3 << 28, // C clear Unsigned lower.
+ mi = 4 << 28, // N set Negative.
+ pl = 5 << 28, // N clear Positive or zero.
+ vs = 6 << 28, // V set Overflow.
+ vc = 7 << 28, // V clear No overflow.
+ hi = 8 << 28, // C set, Z clear Unsigned higher.
+ ls = 9 << 28, // C clear or Z set Unsigned lower or same.
+ ge = 10 << 28, // N == V Greater or equal.
+ lt = 11 << 28, // N != V Less than.
+ gt = 12 << 28, // Z clear, N == V Greater than.
+ le = 13 << 28, // Z set or N != V Less then or equal
+ al = 14 << 28, // Always.
+
+ kSpecialCondition = 15 << 28, // Special condition (refer to section A3.2.1).
+ kNumberOfConditions = 16,
+
+ // Aliases.
+ hs = cs, // C set Unsigned higher or same.
+ lo = cc // C clear Unsigned lower.
+};
+
+inline Condition NegateCondition(Condition cond) {
+ MOZ_ASSERT(cond != al);
+ return static_cast<Condition>(cond ^ ne);
+}
+
+// Commute a condition such that {a cond b == b cond' a}.
+inline Condition CommuteCondition(Condition cond) {
+ switch (cond) {
+ case lo:
+ return hi;
+ case hi:
+ return lo;
+ case hs:
+ return ls;
+ case ls:
+ return hs;
+ case lt:
+ return gt;
+ case gt:
+ return lt;
+ case ge:
+ return le;
+ case le:
+ return ge;
+ default:
+ return cond;
+ }
+}
+
+// -----------------------------------------------------------------------------
+// Instructions encoding.
+
+// Instr is merely used by the Assembler to distinguish 32bit integers
+// representing instructions from usual 32 bit values.
+// Instruction objects are pointers to 32bit values, and provide methods to
+// access the various ISA fields.
+typedef int32_t Instr;
+
+// Opcodes for Data-processing instructions (instructions with a type 0 and 1)
+// as defined in section A3.4
+enum Opcode {
+ AND = 0 << 21, // Logical AND.
+ EOR = 1 << 21, // Logical Exclusive OR.
+ SUB = 2 << 21, // Subtract.
+ RSB = 3 << 21, // Reverse Subtract.
+ ADD = 4 << 21, // Add.
+ ADC = 5 << 21, // Add with Carry.
+ SBC = 6 << 21, // Subtract with Carry.
+ RSC = 7 << 21, // Reverse Subtract with Carry.
+ TST = 8 << 21, // Test.
+ TEQ = 9 << 21, // Test Equivalence.
+ CMP = 10 << 21, // Compare.
+ CMN = 11 << 21, // Compare Negated.
+ ORR = 12 << 21, // Logical (inclusive) OR.
+ MOV = 13 << 21, // Move.
+ BIC = 14 << 21, // Bit Clear.
+ MVN = 15 << 21 // Move Not.
+};
+
+// The bits for bit 7-4 for some type 0 miscellaneous instructions.
+enum MiscInstructionsBits74 {
+ // With bits 22-21 01.
+ BX = 1 << 4,
+ BXJ = 2 << 4,
+ BLX = 3 << 4,
+ BKPT = 7 << 4,
+
+ // With bits 22-21 11.
+ CLZ = 1 << 4
+};
+
+// Load and store exclusive instructions.
+
+// Bit positions.
+enum {
+ ExclusiveOpHi = 24, // Hi bit of opcode field
+ ExclusiveOpLo = 23, // Lo bit of opcode field
+ ExclusiveSizeHi = 22, // Hi bit of operand size field
+ ExclusiveSizeLo = 21, // Lo bit of operand size field
+ ExclusiveLoad = 20 // Bit indicating load
+};
+
+// Opcode bits for exclusive instructions.
+enum { ExclusiveOpcode = 3 };
+
+// Operand size, Bits(ExclusiveSizeHi,ExclusiveSizeLo).
+enum {
+ ExclusiveWord = 0,
+ ExclusiveDouble = 1,
+ ExclusiveByte = 2,
+ ExclusiveHalf = 3
+};
+
+// Instruction encoding bits and masks.
+enum {
+ H = 1 << 5, // Halfword (or byte).
+ S6 = 1 << 6, // Signed (or unsigned).
+ L = 1 << 20, // Load (or store).
+ S = 1 << 20, // Set condition code (or leave unchanged).
+ W = 1 << 21, // Writeback base register (or leave unchanged).
+ A = 1 << 21, // Accumulate in multiply instruction (or not).
+ B = 1 << 22, // Unsigned byte (or word).
+ N = 1 << 22, // Long (or short).
+ U = 1 << 23, // Positive (or negative) offset/index.
+ P = 1 << 24, // Offset/pre-indexed addressing (or post-indexed addressing).
+ I = 1 << 25, // Immediate shifter operand (or not).
+ B0 = 1 << 0,
+ B4 = 1 << 4,
+ B5 = 1 << 5,
+ B6 = 1 << 6,
+ B7 = 1 << 7,
+ B8 = 1 << 8,
+ B9 = 1 << 9,
+ B12 = 1 << 12,
+ B16 = 1 << 16,
+ B17 = 1 << 17,
+ B18 = 1 << 18,
+ B19 = 1 << 19,
+ B20 = 1 << 20,
+ B21 = 1 << 21,
+ B22 = 1 << 22,
+ B23 = 1 << 23,
+ B24 = 1 << 24,
+ B25 = 1 << 25,
+ B26 = 1 << 26,
+ B27 = 1 << 27,
+ B28 = 1 << 28,
+
+ // Instruction bit masks.
+ kCondMask = 15 << 28,
+ kALUMask = 0x6f << 21,
+ kRdMask = 15 << 12, // In str instruction.
+ kCoprocessorMask = 15 << 8,
+ kOpCodeMask = 15 << 21, // In data-processing instructions.
+ kImm24Mask = (1 << 24) - 1,
+ kImm16Mask = (1 << 16) - 1,
+ kImm8Mask = (1 << 8) - 1,
+ kOff12Mask = (1 << 12) - 1,
+ kOff8Mask = (1 << 8) - 1
+};
+
+// -----------------------------------------------------------------------------
+// Addressing modes and instruction variants.
+
+// Condition code updating mode.
+enum SBit {
+ SetCC = 1 << 20, // Set condition code.
+ LeaveCC = 0 << 20 // Leave condition code unchanged.
+};
+
+// Status register selection.
+enum SRegister { CPSR = 0 << 22, SPSR = 1 << 22 };
+
+// Shifter types for Data-processing operands as defined in section A5.1.2.
+enum ShiftOp {
+ LSL = 0 << 5, // Logical shift left.
+ LSR = 1 << 5, // Logical shift right.
+ ASR = 2 << 5, // Arithmetic shift right.
+ ROR = 3 << 5, // Rotate right.
+
+ // RRX is encoded as ROR with shift_imm == 0.
+ // Use a special code to make the distinction. The RRX ShiftOp is only used
+ // as an argument, and will never actually be encoded. The Assembler will
+ // detect it and emit the correct ROR shift operand with shift_imm == 0.
+ RRX = -1,
+ kNumberOfShifts = 4
+};
+
+// Status register fields.
+enum SRegisterField {
+ CPSR_c = CPSR | 1 << 16,
+ CPSR_x = CPSR | 1 << 17,
+ CPSR_s = CPSR | 1 << 18,
+ CPSR_f = CPSR | 1 << 19,
+ SPSR_c = SPSR | 1 << 16,
+ SPSR_x = SPSR | 1 << 17,
+ SPSR_s = SPSR | 1 << 18,
+ SPSR_f = SPSR | 1 << 19
+};
+
+// Status register field mask (or'ed SRegisterField enum values).
+typedef uint32_t SRegisterFieldMask;
+
+// Memory operand addressing mode.
+enum AddrMode {
+ // Bit encoding P U W.
+ Offset = (8 | 4 | 0) << 21, // Offset (without writeback to base).
+ PreIndex = (8 | 4 | 1) << 21, // Pre-indexed addressing with writeback.
+ PostIndex = (0 | 4 | 0) << 21, // Post-indexed addressing with writeback.
+ NegOffset =
+ (8 | 0 | 0) << 21, // Negative offset (without writeback to base).
+ NegPreIndex = (8 | 0 | 1) << 21, // Negative pre-indexed with writeback.
+ NegPostIndex = (0 | 0 | 0) << 21 // Negative post-indexed with writeback.
+};
+
+// Load/store multiple addressing mode.
+enum BlockAddrMode {
+ // Bit encoding P U W .
+ da = (0 | 0 | 0) << 21, // Decrement after.
+ ia = (0 | 4 | 0) << 21, // Increment after.
+ db = (8 | 0 | 0) << 21, // Decrement before.
+ ib = (8 | 4 | 0) << 21, // Increment before.
+ da_w = (0 | 0 | 1) << 21, // Decrement after with writeback to base.
+ ia_w = (0 | 4 | 1) << 21, // Increment after with writeback to base.
+ db_w = (8 | 0 | 1) << 21, // Decrement before with writeback to base.
+ ib_w = (8 | 4 | 1) << 21, // Increment before with writeback to base.
+
+ // Alias modes for comparison when writeback does not matter.
+ da_x = (0 | 0 | 0) << 21, // Decrement after.
+ ia_x = (0 | 4 | 0) << 21, // Increment after.
+ db_x = (8 | 0 | 0) << 21, // Decrement before.
+ ib_x = (8 | 4 | 0) << 21, // Increment before.
+
+ kBlockAddrModeMask = (8 | 4 | 1) << 21
+};
+
+// Coprocessor load/store operand size.
+enum LFlag {
+ Long = 1 << 22, // Long load/store coprocessor.
+ Short = 0 << 22 // Short load/store coprocessor.
+};
+
+// NEON data type
+enum NeonDataType {
+ NeonS8 = 0x1, // U = 0, imm3 = 0b001
+ NeonS16 = 0x2, // U = 0, imm3 = 0b010
+ NeonS32 = 0x4, // U = 0, imm3 = 0b100
+ NeonU8 = 1 << 24 | 0x1, // U = 1, imm3 = 0b001
+ NeonU16 = 1 << 24 | 0x2, // U = 1, imm3 = 0b010
+ NeonU32 = 1 << 24 | 0x4, // U = 1, imm3 = 0b100
+ NeonDataTypeSizeMask = 0x7,
+ NeonDataTypeUMask = 1 << 24
+};
+
+enum NeonListType { nlt_1 = 0x7, nlt_2 = 0xA, nlt_3 = 0x6, nlt_4 = 0x2 };
+
+enum NeonSize { Neon8 = 0x0, Neon16 = 0x1, Neon32 = 0x2, Neon64 = 0x3 };
+
+// -----------------------------------------------------------------------------
+// Supervisor Call (svc) specific support.
+
+// Special Software Interrupt codes when used in the presence of the ARM
+// simulator.
+// svc (formerly swi) provides a 24bit immediate value. Use bits 22:0 for
+// standard SoftwareInterrupCode. Bit 23 is reserved for the stop feature.
+enum SoftwareInterruptCodes {
+ // transition to C code
+ kCallRtRedirected = 0x10,
+ // break point
+ kBreakpoint = 0x20,
+ // stop
+ kStopCode = 1 << 23
+};
+const uint32_t kStopCodeMask = kStopCode - 1;
+const uint32_t kMaxStopCode = kStopCode - 1;
+const int32_t kDefaultStopCode = -1;
+
+// Type of VFP register. Determines register encoding.
+enum VFPRegPrecision { kSinglePrecision = 0, kDoublePrecision = 1 };
+
+// VFP FPSCR constants.
+enum VFPConversionMode { kFPSCRRounding = 0, kDefaultRoundToZero = 1 };
+
+// This mask does not include the "inexact" or "input denormal" cumulative
+// exceptions flags, because we usually don't want to check for it.
+const uint32_t kVFPExceptionMask = 0xf;
+const uint32_t kVFPInvalidOpExceptionBit = 1 << 0;
+const uint32_t kVFPOverflowExceptionBit = 1 << 2;
+const uint32_t kVFPUnderflowExceptionBit = 1 << 3;
+const uint32_t kVFPInexactExceptionBit = 1 << 4;
+const uint32_t kVFPFlushToZeroMask = 1 << 24;
+const uint32_t kVFPDefaultNaNModeControlBit = 1 << 25;
+
+const uint32_t kVFPNConditionFlagBit = 1 << 31;
+const uint32_t kVFPZConditionFlagBit = 1 << 30;
+const uint32_t kVFPCConditionFlagBit = 1 << 29;
+const uint32_t kVFPVConditionFlagBit = 1 << 28;
+
+// VFP rounding modes. See ARM DDI 0406B Page A2-29.
+enum VFPRoundingMode {
+ RN = 0 << 22, // Round to Nearest.
+ RP = 1 << 22, // Round towards Plus Infinity.
+ RM = 2 << 22, // Round towards Minus Infinity.
+ RZ = 3 << 22, // Round towards zero.
+
+ // Aliases.
+ kRoundToNearest = RN,
+ kRoundToPlusInf = RP,
+ kRoundToMinusInf = RM,
+ kRoundToZero = RZ
+};
+
+const uint32_t kVFPRoundingModeMask = 3 << 22;
+
+enum CheckForInexactConversion {
+ kCheckForInexactConversion,
+ kDontCheckForInexactConversion
+};
+
+// -----------------------------------------------------------------------------
+// Hints.
+
+// Branch hints are not used on the ARM. They are defined so that they can
+// appear in shared function signatures, but will be ignored in ARM
+// implementations.
+enum Hint { no_hint };
+
+// Hints are not used on the arm. Negating is trivial.
+inline Hint NegateHint(Hint ignored) { return no_hint; }
+
+// -----------------------------------------------------------------------------
+// Instruction abstraction.
+
+// The class Instruction enables access to individual fields defined in the ARM
+// architecture instruction set encoding as described in figure A3-1.
+// Note that the Assembler uses typedef int32_t Instr.
+//
+// Example: Test whether the instruction at ptr does set the condition code
+// bits.
+//
+// bool InstructionSetsConditionCodes(byte* ptr) {
+// Instruction* instr = Instruction::At(ptr);
+// int type = instr->TypeValue();
+// return ((type == 0) || (type == 1)) && instr->HasS();
+// }
+//
+class Instruction {
+ public:
+ enum { kInstrSize = 4, kInstrSizeLog2 = 2, kPCReadOffset = 8 };
+
+ // Helper macro to define static accessors.
+ // We use the cast to char* trick to bypass the strict anti-aliasing rules.
+# define DECLARE_STATIC_TYPED_ACCESSOR(return_type, Name) \
+ static inline return_type Name(Instr instr) { \
+ char* temp = reinterpret_cast<char*>(&instr); \
+ return reinterpret_cast<Instruction*>(temp)->Name(); \
+ }
+
+# define DECLARE_STATIC_ACCESSOR(Name) DECLARE_STATIC_TYPED_ACCESSOR(int, Name)
+
+ // Get the raw instruction bits.
+ inline Instr InstructionBits() const {
+ return *reinterpret_cast<const Instr*>(this);
+ }
+
+ // Set the raw instruction bits to value.
+ inline void SetInstructionBits(Instr value) {
+ *reinterpret_cast<Instr*>(this) = value;
+ }
+
+ // Read one particular bit out of the instruction bits.
+ inline int Bit(int nr) const { return (InstructionBits() >> nr) & 1; }
+
+ // Read a bit field's value out of the instruction bits.
+ inline int Bits(int hi, int lo) const {
+ return (InstructionBits() >> lo) & ((2 << (hi - lo)) - 1);
+ }
+
+ // Read a bit field out of the instruction bits.
+ inline int BitField(int hi, int lo) const {
+ return InstructionBits() & (((2 << (hi - lo)) - 1) << lo);
+ }
+
+ // Static support.
+
+ // Read one particular bit out of the instruction bits.
+ static inline int Bit(Instr instr, int nr) { return (instr >> nr) & 1; }
+
+ // Read the value of a bit field out of the instruction bits.
+ static inline int Bits(Instr instr, int hi, int lo) {
+ return (instr >> lo) & ((2 << (hi - lo)) - 1);
+ }
+
+ // Read a bit field out of the instruction bits.
+ static inline int BitField(Instr instr, int hi, int lo) {
+ return instr & (((2 << (hi - lo)) - 1) << lo);
+ }
+
+ // Accessors for the different named fields used in the ARM encoding.
+ // The naming of these accessor corresponds to figure A3-1.
+ //
+ // Two kind of accessors are declared:
+ // - <Name>Field() will return the raw field, i.e. the field's bits at their
+ // original place in the instruction encoding.
+ // e.g. if instr is the 'addgt r0, r1, r2' instruction, encoded as
+ // 0xC0810002 ConditionField(instr) will return 0xC0000000.
+ // - <Name>Value() will return the field value, shifted back to bit 0.
+ // e.g. if instr is the 'addgt r0, r1, r2' instruction, encoded as
+ // 0xC0810002 ConditionField(instr) will return 0xC.
+
+ // Generally applicable fields
+ inline Condition ConditionValue() const {
+ return static_cast<Condition>(Bits(31, 28));
+ }
+ inline Condition ConditionField() const {
+ return static_cast<Condition>(BitField(31, 28));
+ }
+ DECLARE_STATIC_TYPED_ACCESSOR(Condition, ConditionValue);
+ DECLARE_STATIC_TYPED_ACCESSOR(Condition, ConditionField);
+
+ inline int TypeValue() const { return Bits(27, 25); }
+ inline int SpecialValue() const { return Bits(27, 23); }
+
+ inline int RnValue() const { return Bits(19, 16); }
+ DECLARE_STATIC_ACCESSOR(RnValue);
+ inline int RdValue() const { return Bits(15, 12); }
+ DECLARE_STATIC_ACCESSOR(RdValue);
+
+ inline int CoprocessorValue() const { return Bits(11, 8); }
+ // Support for VFP.
+ // Vn(19-16) | Vd(15-12) | Vm(3-0)
+ inline int VnValue() const { return Bits(19, 16); }
+ inline int VmValue() const { return Bits(3, 0); }
+ inline int VdValue() const { return Bits(15, 12); }
+ inline int NValue() const { return Bit(7); }
+ inline int MValue() const { return Bit(5); }
+ inline int DValue() const { return Bit(22); }
+ inline int RtValue() const { return Bits(15, 12); }
+ inline int PValue() const { return Bit(24); }
+ inline int UValue() const { return Bit(23); }
+ inline int Opc1Value() const { return (Bit(23) << 2) | Bits(21, 20); }
+ inline int Opc2Value() const { return Bits(19, 16); }
+ inline int Opc3Value() const { return Bits(7, 6); }
+ inline int SzValue() const { return Bit(8); }
+ inline int VLValue() const { return Bit(20); }
+ inline int VCValue() const { return Bit(8); }
+ inline int VAValue() const { return Bits(23, 21); }
+ inline int VBValue() const { return Bits(6, 5); }
+ inline int VFPNRegValue(VFPRegPrecision pre) {
+ return VFPGlueRegValue(pre, 16, 7);
+ }
+ inline int VFPMRegValue(VFPRegPrecision pre) {
+ return VFPGlueRegValue(pre, 0, 5);
+ }
+ inline int VFPDRegValue(VFPRegPrecision pre) {
+ return VFPGlueRegValue(pre, 12, 22);
+ }
+
+ // Fields used in Data processing instructions
+ inline int OpcodeValue() const { return static_cast<Opcode>(Bits(24, 21)); }
+ inline Opcode OpcodeField() const {
+ return static_cast<Opcode>(BitField(24, 21));
+ }
+ inline int SValue() const { return Bit(20); }
+ // with register
+ inline int RmValue() const { return Bits(3, 0); }
+ DECLARE_STATIC_ACCESSOR(RmValue);
+ inline int ShiftValue() const { return static_cast<ShiftOp>(Bits(6, 5)); }
+ inline ShiftOp ShiftField() const {
+ return static_cast<ShiftOp>(BitField(6, 5));
+ }
+ inline int RegShiftValue() const { return Bit(4); }
+ inline int RsValue() const { return Bits(11, 8); }
+ inline int ShiftAmountValue() const { return Bits(11, 7); }
+ // with immediate
+ inline int RotateValue() const { return Bits(11, 8); }
+ DECLARE_STATIC_ACCESSOR(RotateValue);
+ inline int Immed8Value() const { return Bits(7, 0); }
+ DECLARE_STATIC_ACCESSOR(Immed8Value);
+ inline int Immed4Value() const { return Bits(19, 16); }
+ inline int ImmedMovwMovtValue() const {
+ return Immed4Value() << 12 | Offset12Value();
+ }
+ DECLARE_STATIC_ACCESSOR(ImmedMovwMovtValue);
+
+ // Fields used in Load/Store instructions
+ inline int PUValue() const { return Bits(24, 23); }
+ inline int PUField() const { return BitField(24, 23); }
+ inline int BValue() const { return Bit(22); }
+ inline int WValue() const { return Bit(21); }
+ inline int LValue() const { return Bit(20); }
+ // with register uses same fields as Data processing instructions above
+ // with immediate
+ inline int Offset12Value() const { return Bits(11, 0); }
+ // multiple
+ inline int RlistValue() const { return Bits(15, 0); }
+ // extra loads and stores
+ inline int SignValue() const { return Bit(6); }
+ inline int HValue() const { return Bit(5); }
+ inline int ImmedHValue() const { return Bits(11, 8); }
+ inline int ImmedLValue() const { return Bits(3, 0); }
+
+ // Fields used in Branch instructions
+ inline int LinkValue() const { return Bit(24); }
+ inline int SImmed24Value() const { return ((InstructionBits() << 8) >> 8); }
+
+ // Fields used in Software interrupt instructions
+ inline SoftwareInterruptCodes SvcValue() const {
+ return static_cast<SoftwareInterruptCodes>(Bits(23, 0));
+ }
+
+ // Test for special encodings of type 0 instructions (extra loads and stores,
+ // as well as multiplications).
+ inline bool IsSpecialType0() const { return (Bit(7) == 1) && (Bit(4) == 1); }
+
+ // Test for miscellaneous instructions encodings of type 0 instructions.
+ inline bool IsMiscType0() const {
+ return (Bit(24) == 1) && (Bit(23) == 0) && (Bit(20) == 0) &&
+ ((Bit(7) == 0));
+ }
+
+ // Test for a nop instruction, which falls under type 1.
+ inline bool IsNopType1() const { return Bits(24, 0) == 0x0120F000; }
+
+ // Test for a nop instruction, which falls under type 1.
+ inline bool IsCsdbType1() const { return Bits(24, 0) == 0x0120F014; }
+
+ // Test for a stop instruction.
+ inline bool IsStop() const {
+ return (TypeValue() == 7) && (Bit(24) == 1) && (SvcValue() >= kStopCode);
+ }
+
+ // Special accessors that test for existence of a value.
+ inline bool HasS() const { return SValue() == 1; }
+ inline bool HasB() const { return BValue() == 1; }
+ inline bool HasW() const { return WValue() == 1; }
+ inline bool HasL() const { return LValue() == 1; }
+ inline bool HasU() const { return UValue() == 1; }
+ inline bool HasSign() const { return SignValue() == 1; }
+ inline bool HasH() const { return HValue() == 1; }
+ inline bool HasLink() const { return LinkValue() == 1; }
+
+ // Decoding the double immediate in the vmov instruction.
+ double DoubleImmedVmov() const;
+
+ // Instructions are read of out a code stream. The only way to get a
+ // reference to an instruction is to convert a pointer. There is no way
+ // to allocate or create instances of class Instruction.
+ // Use the At(pc) function to create references to Instruction.
+ static Instruction* At(uint8_t* pc) {
+ return reinterpret_cast<Instruction*>(pc);
+ }
+
+ private:
+ // Join split register codes, depending on single or double precision.
+ // four_bit is the position of the least-significant bit of the four
+ // bit specifier. one_bit is the position of the additional single bit
+ // specifier.
+ inline int VFPGlueRegValue(VFPRegPrecision pre, int four_bit, int one_bit) {
+ if (pre == kSinglePrecision) {
+ return (Bits(four_bit + 3, four_bit) << 1) | Bit(one_bit);
+ }
+ return (Bit(one_bit) << 4) | Bits(four_bit + 3, four_bit);
+ }
+
+ // We need to prevent the creation of instances of class Instruction.
+ Instruction() = delete;
+ Instruction(const Instruction&) = delete;
+ void operator=(const Instruction&) = delete;
+};
+
+// Helper functions for converting between register numbers and names.
+class Registers {
+ public:
+ // Return the name of the register.
+ static const char* Name(int reg);
+
+ // Lookup the register number for the name provided.
+ static int Number(const char* name);
+
+ struct RegisterAlias {
+ int reg;
+ const char* name;
+ };
+
+ private:
+ static const char* names_[kNumRegisters];
+ static const RegisterAlias aliases_[];
+};
+
+// Helper functions for converting between VFP register numbers and names.
+class VFPRegisters {
+ public:
+ // Return the name of the register.
+ static const char* Name(int reg, bool is_double);
+
+ // Lookup the register number for the name provided.
+ // Set flag pointed by is_double to true if register
+ // is double-precision.
+ static int Number(const char* name, bool* is_double);
+
+ private:
+ static const char* names_[kNumVFPRegisters];
+};
+
+} // namespace disasm
+} // namespace jit
+} // namespace js
+
+#endif // JS_DISASM_ARM
+
+#endif // jit_arm_disasm_Constants_arm_h