MIPS: r6 compact branch optimization.

src/mips/constants-mips.h

Index: src/mips/constants-mips.h
diff --git a/src/mips/constants-mips.h b/src/mips/constants-mips.h
index 813e33a7f09ce002a22afc96be1ffcae237d1c49..b0c2ebbdf8ac20a88dccd196d0e44d488951eb58 100644
--- a/src/mips/constants-mips.h
+++ b/src/mips/constants-mips.h
@@ -298,311 +298,319 @@ const int kFBtrueBits    = 1;
 
 // ----- Miscellaneous useful masks.
 // Instruction bit masks.
-const int  kOpcodeMask   = ((1 << kOpcodeBits) - 1) << kOpcodeShift;
-const int  kImm16Mask    = ((1 << kImm16Bits) - 1) << kImm16Shift;
+const int kOpcodeMask = ((1 << kOpcodeBits) - 1) << kOpcodeShift;
+const int kImm16Mask = ((1 << kImm16Bits) - 1) << kImm16Shift;
 const int kImm18Mask = ((1 << kImm18Bits) - 1) << kImm18Shift;
 const int kImm19Mask = ((1 << kImm19Bits) - 1) << kImm19Shift;
 const int kImm21Mask = ((1 << kImm21Bits) - 1) << kImm21Shift;
-const int  kImm26Mask    = ((1 << kImm26Bits) - 1) << kImm26Shift;
-const int  kImm28Mask    = ((1 << kImm28Bits) - 1) << kImm28Shift;
-const int  kRsFieldMask  = ((1 << kRsBits) - 1) << kRsShift;
-const int  kRtFieldMask  = ((1 << kRtBits) - 1) << kRtShift;
-const int  kRdFieldMask  = ((1 << kRdBits) - 1) << kRdShift;
-const int  kSaFieldMask  = ((1 << kSaBits) - 1) << kSaShift;
-const int  kFunctionFieldMask = ((1 << kFunctionBits) - 1) << kFunctionShift;
+const int kImm26Mask = ((1 << kImm26Bits) - 1) << kImm26Shift;
+const int kImm28Mask = ((1 << kImm28Bits) - 1) << kImm28Shift;
+const int kRsFieldMask = ((1 << kRsBits) - 1) << kRsShift;
+const int kRtFieldMask = ((1 << kRtBits) - 1) << kRtShift;
+const int kRdFieldMask = ((1 << kRdBits) - 1) << kRdShift;
+const int kSaFieldMask = ((1 << kSaBits) - 1) << kSaShift;
+const int kFunctionFieldMask = ((1 << kFunctionBits) - 1) << kFunctionShift;
 // Misc masks.
-const int  kHiMask       =   0xffff << 16;
-const int  kLoMask       =   0xffff;
-const int  kSignMask     =   0x80000000;
-const int  kJumpAddrMask = (1 << (kImm26Bits + kImmFieldShift)) - 1;
+const int kHiMask = 0xffff << 16;
+const int kLoMask = 0xffff;
+const int kSignMask = 0x80000000;
+const int kJumpAddrMask = (1 << (kImm26Bits + kImmFieldShift)) - 1;
 
 // ----- MIPS Opcodes and Function Fields.
 // We use this presentation to stay close to the table representation in
 // MIPS32 Architecture For Programmers, Volume II: The MIPS32 Instruction Set.
-enum Opcode {
-  SPECIAL = 0 << kOpcodeShift,
-  REGIMM = 1 << kOpcodeShift,
-
-  J = ((0 << 3) + 2) << kOpcodeShift,
-  JAL = ((0 << 3) + 3) << kOpcodeShift,
-  BEQ = ((0 << 3) + 4) << kOpcodeShift,
-  BNE = ((0 << 3) + 5) << kOpcodeShift,
-  BLEZ = ((0 << 3) + 6) << kOpcodeShift,
-  BGTZ = ((0 << 3) + 7) << kOpcodeShift,
-
-  ADDI = ((1 << 3) + 0) << kOpcodeShift,
-  ADDIU = ((1 << 3) + 1) << kOpcodeShift,
-  SLTI = ((1 << 3) + 2) << kOpcodeShift,
-  SLTIU = ((1 << 3) + 3) << kOpcodeShift,
-  ANDI = ((1 << 3) + 4) << kOpcodeShift,
-  ORI = ((1 << 3) + 5) << kOpcodeShift,
-  XORI = ((1 << 3) + 6) << kOpcodeShift,
-  LUI = ((1 << 3) + 7) << kOpcodeShift,  // LUI/AUI family.
-
-  BEQC = ((2 << 3) + 0) << kOpcodeShift,
-  COP1 = ((2 << 3) + 1) << kOpcodeShift,  // Coprocessor 1 class.
-  BEQL = ((2 << 3) + 4) << kOpcodeShift,
-  BNEL = ((2 << 3) + 5) << kOpcodeShift,
-  BLEZL = ((2 << 3) + 6) << kOpcodeShift,
-  BGTZL = ((2 << 3) + 7) << kOpcodeShift,
-
-  DADDI = ((3 << 3) + 0) << kOpcodeShift,  // This is also BNEC.
-  SPECIAL2 = ((3 << 3) + 4) << kOpcodeShift,
-  SPECIAL3 = ((3 << 3) + 7) << kOpcodeShift,
-
-  LB = ((4 << 3) + 0) << kOpcodeShift,
-  LH = ((4 << 3) + 1) << kOpcodeShift,
-  LWL = ((4 << 3) + 2) << kOpcodeShift,
-  LW = ((4 << 3) + 3) << kOpcodeShift,
-  LBU = ((4 << 3) + 4) << kOpcodeShift,
-  LHU = ((4 << 3) + 5) << kOpcodeShift,
-  LWR = ((4 << 3) + 6) << kOpcodeShift,
-  SB = ((5 << 3) + 0) << kOpcodeShift,
-  SH = ((5 << 3) + 1) << kOpcodeShift,
-  SWL = ((5 << 3) + 2) << kOpcodeShift,
-  SW = ((5 << 3) + 3) << kOpcodeShift,
-  SWR = ((5 << 3) + 6) << kOpcodeShift,
-
-  LWC1 = ((6 << 3) + 1) << kOpcodeShift,
-  BC = ((6 << 3) + 2) << kOpcodeShift,
-  LDC1 = ((6 << 3) + 5) << kOpcodeShift,
-  POP66 = ((6 << 3) + 6) << kOpcodeShift,
-
-  PREF = ((6 << 3) + 3) << kOpcodeShift,
-
-  SWC1 = ((7 << 3) + 1) << kOpcodeShift,
-  BALC = ((7 << 3) + 2) << kOpcodeShift,
-  PCREL = ((7 << 3) + 3) << kOpcodeShift,
-  SDC1 = ((7 << 3) + 5) << kOpcodeShift,
-  POP76 = ((7 << 3) + 6) << kOpcodeShift,
-
-  COP1X = ((1 << 4) + 3) << kOpcodeShift
+enum Opcode : uint32_t {
+  SPECIAL = 0U << kOpcodeShift,
+  REGIMM = 1U << kOpcodeShift,
+
+  J = ((0U << 3) + 2) << kOpcodeShift,
+  JAL = ((0U << 3) + 3) << kOpcodeShift,
+  BEQ = ((0U << 3) + 4) << kOpcodeShift,
+  BNE = ((0U << 3) + 5) << kOpcodeShift,
+  BLEZ = ((0U << 3) + 6) << kOpcodeShift,
+  BGTZ = ((0U << 3) + 7) << kOpcodeShift,
+
+  ADDI = ((1U << 3) + 0) << kOpcodeShift,
+  ADDIU = ((1U << 3) + 1) << kOpcodeShift,
+  SLTI = ((1U << 3) + 2) << kOpcodeShift,
+  SLTIU = ((1U << 3) + 3) << kOpcodeShift,
+  ANDI = ((1U << 3) + 4) << kOpcodeShift,
+  ORI = ((1U << 3) + 5) << kOpcodeShift,
+  XORI = ((1U << 3) + 6) << kOpcodeShift,
+  LUI = ((1U << 3) + 7) << kOpcodeShift,  // LUI/AUI family.
+
+  BEQC = ((2U << 3) + 0) << kOpcodeShift,
+  COP1 = ((2U << 3) + 1) << kOpcodeShift,  // Coprocessor 1 class.
+  BEQL = ((2U << 3) + 4) << kOpcodeShift,
+  BNEL = ((2U << 3) + 5) << kOpcodeShift,
+  BLEZL = ((2U << 3) + 6) << kOpcodeShift,
+  BGTZL = ((2U << 3) + 7) << kOpcodeShift,
+
+  DADDI = ((3U << 3) + 0) << kOpcodeShift,  // This is also BNEC.
+  SPECIAL2 = ((3U << 3) + 4) << kOpcodeShift,
+  SPECIAL3 = ((3U << 3) + 7) << kOpcodeShift,
+
+  LB = ((4U << 3) + 0) << kOpcodeShift,
+  LH = ((4U << 3) + 1) << kOpcodeShift,
+  LWL = ((4U << 3) + 2) << kOpcodeShift,
+  LW = ((4U << 3) + 3) << kOpcodeShift,
+  LBU = ((4U << 3) + 4) << kOpcodeShift,
+  LHU = ((4U << 3) + 5) << kOpcodeShift,
+  LWR = ((4U << 3) + 6) << kOpcodeShift,
+  SB = ((5U << 3) + 0) << kOpcodeShift,
+  SH = ((5U << 3) + 1) << kOpcodeShift,
+  SWL = ((5U << 3) + 2) << kOpcodeShift,
+  SW = ((5U << 3) + 3) << kOpcodeShift,
+  SWR = ((5U << 3) + 6) << kOpcodeShift,
+
+  LWC1 = ((6U << 3) + 1) << kOpcodeShift,
+  BC = ((6U << 3) + 2) << kOpcodeShift,
+  LDC1 = ((6U << 3) + 5) << kOpcodeShift,
+  POP66 = ((6U << 3) + 6) << kOpcodeShift,  // beqzc, jic
+
+  PREF = ((6U << 3) + 3) << kOpcodeShift,
+
+  SWC1 = ((7U << 3) + 1) << kOpcodeShift,
+  BALC = ((7U << 3) + 2) << kOpcodeShift,
+  PCREL = ((7U << 3) + 3) << kOpcodeShift,
+  SDC1 = ((7U << 3) + 5) << kOpcodeShift,
+  POP76 = ((7U << 3) + 6) << kOpcodeShift,  // bnezc, jialc
+
+  COP1X = ((1U << 4) + 3) << kOpcodeShift,
+
+  // New r6 instruction.
+  POP06 = BLEZ,   // bgeuc/bleuc, blezalc, bgezalc
+  POP07 = BGTZ,   // bltuc/bgtuc, bgtzalc, bltzalc
+  POP10 = ADDI,   // beqzalc, bovc, beqc
+  POP26 = BLEZL,  // bgezc, blezc, bgec/blec
+  POP27 = BGTZL,  // bgtzc, bltzc, bltc/bgtc
+  POP30 = DADDI,  // bnezalc, bvnc, bnec
 };
 
-enum SecondaryField {
+enum SecondaryField : uint32_t {
   // SPECIAL Encoding of Function Field.
-  SLL = ((0 << 3) + 0),
-  MOVCI = ((0 << 3) + 1),
-  SRL = ((0 << 3) + 2),
-  SRA = ((0 << 3) + 3),
-  SLLV = ((0 << 3) + 4),
-  SRLV = ((0 << 3) + 6),
-  SRAV = ((0 << 3) + 7),
-
-  JR = ((1 << 3) + 0),
-  JALR = ((1 << 3) + 1),
-  MOVZ = ((1 << 3) + 2),
-  MOVN = ((1 << 3) + 3),
-  BREAK = ((1 << 3) + 5),
-
-  MFHI = ((2 << 3) + 0),
-  CLZ_R6 = ((2 << 3) + 0),
-  CLO_R6 = ((2 << 3) + 1),
-  MFLO = ((2 << 3) + 2),
-
-  MULT = ((3 << 3) + 0),
-  MULTU = ((3 << 3) + 1),
-  DIV = ((3 << 3) + 2),
-  DIVU = ((3 << 3) + 3),
-
-  ADD = ((4 << 3) + 0),
-  ADDU = ((4 << 3) + 1),
-  SUB = ((4 << 3) + 2),
-  SUBU = ((4 << 3) + 3),
-  AND = ((4 << 3) + 4),
-  OR = ((4 << 3) + 5),
-  XOR = ((4 << 3) + 6),
-  NOR = ((4 << 3) + 7),
-
-  SLT = ((5 << 3) + 2),
-  SLTU = ((5 << 3) + 3),
-
-  TGE = ((6 << 3) + 0),
-  TGEU = ((6 << 3) + 1),
-  TLT = ((6 << 3) + 2),
-  TLTU = ((6 << 3) + 3),
-  TEQ = ((6 << 3) + 4),
-  SELEQZ_S = ((6 << 3) + 5),
-  TNE = ((6 << 3) + 6),
-  SELNEZ_S = ((6 << 3) + 7),
+  SLL = ((0U << 3) + 0),
+  MOVCI = ((0U << 3) + 1),
+  SRL = ((0U << 3) + 2),
+  SRA = ((0U << 3) + 3),
+  SLLV = ((0U << 3) + 4),
+  SRLV = ((0U << 3) + 6),
+  SRAV = ((0U << 3) + 7),
+
+  JR = ((1U << 3) + 0),
+  JALR = ((1U << 3) + 1),
+  MOVZ = ((1U << 3) + 2),
+  MOVN = ((1U << 3) + 3),
+  BREAK = ((1U << 3) + 5),
+
+  MFHI = ((2U << 3) + 0),
+  CLZ_R6 = ((2U << 3) + 0),
+  CLO_R6 = ((2U << 3) + 1),
+  MFLO = ((2U << 3) + 2),
+
+  MULT = ((3U << 3) + 0),
+  MULTU = ((3U << 3) + 1),
+  DIV = ((3U << 3) + 2),
+  DIVU = ((3U << 3) + 3),
+
+  ADD = ((4U << 3) + 0),
+  ADDU = ((4U << 3) + 1),
+  SUB = ((4U << 3) + 2),
+  SUBU = ((4U << 3) + 3),
+  AND = ((4U << 3) + 4),
+  OR = ((4U << 3) + 5),
+  XOR = ((4U << 3) + 6),
+  NOR = ((4U << 3) + 7),
+
+  SLT = ((5U << 3) + 2),
+  SLTU = ((5U << 3) + 3),
+
+  TGE = ((6U << 3) + 0),
+  TGEU = ((6U << 3) + 1),
+  TLT = ((6U << 3) + 2),
+  TLTU = ((6U << 3) + 3),
+  TEQ = ((6U << 3) + 4),
+  SELEQZ_S = ((6U << 3) + 5),
+  TNE = ((6U << 3) + 6),
+  SELNEZ_S = ((6U << 3) + 7),
 
   // Multiply integers in r6.
-  MUL_MUH = ((3 << 3) + 0),    // MUL, MUH.
-  MUL_MUH_U = ((3 << 3) + 1),  // MUL_U, MUH_U.
-  RINT = ((3 << 3) + 2),
+  MUL_MUH = ((3U << 3) + 0),    // MUL, MUH.
+  MUL_MUH_U = ((3U << 3) + 1),  // MUL_U, MUH_U.
+  RINT = ((3U << 3) + 2),
 
-  MUL_OP = ((0 << 3) + 2),
-  MUH_OP = ((0 << 3) + 3),
-  DIV_OP = ((0 << 3) + 2),
-  MOD_OP = ((0 << 3) + 3),
+  MUL_OP = ((0U << 3) + 2),
+  MUH_OP = ((0U << 3) + 3),
+  DIV_OP = ((0U << 3) + 2),
+  MOD_OP = ((0U << 3) + 3),
 
-  DIV_MOD = ((3 << 3) + 2),
-  DIV_MOD_U = ((3 << 3) + 3),
+  DIV_MOD = ((3U << 3) + 2),
+  DIV_MOD_U = ((3U << 3) + 3),
 
   // SPECIAL2 Encoding of Function Field.
-  MUL = ((0 << 3) + 2),
-  CLZ = ((4 << 3) + 0),
-  CLO = ((4 << 3) + 1),
+  MUL = ((0U << 3) + 2),
+  CLZ = ((4U << 3) + 0),
+  CLO = ((4U << 3) + 1),
 
   // SPECIAL3 Encoding of Function Field.
-  EXT = ((0 << 3) + 0),
-  INS = ((0 << 3) + 4),
-  BSHFL = ((4 << 3) + 0),
+  EXT = ((0U << 3) + 0),
+  INS = ((0U << 3) + 4),
+  BSHFL = ((4U << 3) + 0),
 
   // SPECIAL3 Encoding of sa Field.
-  BITSWAP = ((0 << 3) + 0),
-  ALIGN = ((0 << 3) + 2),
-  WSBH = ((0 << 3) + 2),
-  SEB = ((2 << 3) + 0),
-  SEH = ((3 << 3) + 0),
+  BITSWAP = ((0U << 3) + 0),
+  ALIGN = ((0U << 3) + 2),
+  WSBH = ((0U << 3) + 2),
+  SEB = ((2U << 3) + 0),
+  SEH = ((3U << 3) + 0),
 
   // REGIMM  encoding of rt Field.
-  BLTZ = ((0 << 3) + 0) << 16,
-  BGEZ = ((0 << 3) + 1) << 16,
-  BLTZAL = ((2 << 3) + 0) << 16,
-  BGEZAL = ((2 << 3) + 1) << 16,
-  BGEZALL = ((2 << 3) + 3) << 16,
+  BLTZ = ((0U << 3) + 0) << 16,
+  BGEZ = ((0U << 3) + 1) << 16,
+  BLTZAL = ((2U << 3) + 0) << 16,
+  BGEZAL = ((2U << 3) + 1) << 16,
+  BGEZALL = ((2U << 3) + 3) << 16,
 
   // COP1 Encoding of rs Field.
-  MFC1 = ((0 << 3) + 0) << 21,
-  CFC1 = ((0 << 3) + 2) << 21,
-  MFHC1 = ((0 << 3) + 3) << 21,
-  MTC1 = ((0 << 3) + 4) << 21,
-  CTC1 = ((0 << 3) + 6) << 21,
-  MTHC1 = ((0 << 3) + 7) << 21,
-  BC1 = ((1 << 3) + 0) << 21,
-  S = ((2 << 3) + 0) << 21,
-  D = ((2 << 3) + 1) << 21,
-  W = ((2 << 3) + 4) << 21,
-  L = ((2 << 3) + 5) << 21,
-  PS = ((2 << 3) + 6) << 21,
+  MFC1 = ((0U << 3) + 0) << 21,
+  CFC1 = ((0U << 3) + 2) << 21,
+  MFHC1 = ((0U << 3) + 3) << 21,
+  MTC1 = ((0U << 3) + 4) << 21,
+  CTC1 = ((0U << 3) + 6) << 21,
+  MTHC1 = ((0U << 3) + 7) << 21,
+  BC1 = ((1U << 3) + 0) << 21,
+  S = ((2U << 3) + 0) << 21,
+  D = ((2U << 3) + 1) << 21,
+  W = ((2U << 3) + 4) << 21,
+  L = ((2U << 3) + 5) << 21,
+  PS = ((2U << 3) + 6) << 21,
   // COP1 Encoding of Function Field When rs=S.
 
-  ADD_S = ((0 << 3) + 0),
-  SUB_S = ((0 << 3) + 1),
-  MUL_S = ((0 << 3) + 2),
-  DIV_S = ((0 << 3) + 3),
-  ABS_S = ((0 << 3) + 5),
-  SQRT_S = ((0 << 3) + 4),
-  MOV_S = ((0 << 3) + 6),
-  NEG_S = ((0 << 3) + 7),
-  ROUND_L_S = ((1 << 3) + 0),
-  TRUNC_L_S = ((1 << 3) + 1),
-  CEIL_L_S = ((1 << 3) + 2),
-  FLOOR_L_S = ((1 << 3) + 3),
-  ROUND_W_S = ((1 << 3) + 4),
-  TRUNC_W_S = ((1 << 3) + 5),
-  CEIL_W_S = ((1 << 3) + 6),
-  FLOOR_W_S = ((1 << 3) + 7),
-  RECIP_S = ((2 << 3) + 5),
-  RSQRT_S = ((2 << 3) + 6),
-  CLASS_S = ((3 << 3) + 3),
-  CVT_D_S = ((4 << 3) + 1),
-  CVT_W_S = ((4 << 3) + 4),
-  CVT_L_S = ((4 << 3) + 5),
-  CVT_PS_S = ((4 << 3) + 6),
+  ADD_S = ((0U << 3) + 0),
+  SUB_S = ((0U << 3) + 1),
+  MUL_S = ((0U << 3) + 2),
+  DIV_S = ((0U << 3) + 3),
+  ABS_S = ((0U << 3) + 5),
+  SQRT_S = ((0U << 3) + 4),
+  MOV_S = ((0U << 3) + 6),
+  NEG_S = ((0U << 3) + 7),
+  ROUND_L_S = ((1U << 3) + 0),
+  TRUNC_L_S = ((1U << 3) + 1),
+  CEIL_L_S = ((1U << 3) + 2),
+  FLOOR_L_S = ((1U << 3) + 3),
+  ROUND_W_S = ((1U << 3) + 4),
+  TRUNC_W_S = ((1U << 3) + 5),
+  CEIL_W_S = ((1U << 3) + 6),
+  FLOOR_W_S = ((1U << 3) + 7),
+  RECIP_S = ((2U << 3) + 5),
+  RSQRT_S = ((2U << 3) + 6),
+  CLASS_S = ((3U << 3) + 3),
+  CVT_D_S = ((4U << 3) + 1),
+  CVT_W_S = ((4U << 3) + 4),
+  CVT_L_S = ((4U << 3) + 5),
+  CVT_PS_S = ((4U << 3) + 6),
 
   // COP1 Encoding of Function Field When rs=D.
-  ADD_D = ((0 << 3) + 0),
-  SUB_D = ((0 << 3) + 1),
-  MUL_D = ((0 << 3) + 2),
-  DIV_D = ((0 << 3) + 3),
-  SQRT_D = ((0 << 3) + 4),
-  ABS_D = ((0 << 3) + 5),
-  MOV_D = ((0 << 3) + 6),
-  NEG_D = ((0 << 3) + 7),
-  ROUND_L_D = ((1 << 3) + 0),
-  TRUNC_L_D = ((1 << 3) + 1),
-  CEIL_L_D = ((1 << 3) + 2),
-  FLOOR_L_D = ((1 << 3) + 3),
-  ROUND_W_D = ((1 << 3) + 4),
-  TRUNC_W_D = ((1 << 3) + 5),
-  CEIL_W_D = ((1 << 3) + 6),
-  FLOOR_W_D = ((1 << 3) + 7),
-  RECIP_D = ((2 << 3) + 5),
-  RSQRT_D = ((2 << 3) + 6),
-  CLASS_D = ((3 << 3) + 3),
-  MIN = ((3 << 3) + 4),
-  MINA = ((3 << 3) + 5),
-  MAX = ((3 << 3) + 6),
-  MAXA = ((3 << 3) + 7),
-  CVT_S_D = ((4 << 3) + 0),
-  CVT_W_D = ((4 << 3) + 4),
-  CVT_L_D = ((4 << 3) + 5),
-  C_F_D = ((6 << 3) + 0),
-  C_UN_D = ((6 << 3) + 1),
-  C_EQ_D = ((6 << 3) + 2),
-  C_UEQ_D = ((6 << 3) + 3),
-  C_OLT_D = ((6 << 3) + 4),
-  C_ULT_D = ((6 << 3) + 5),
-  C_OLE_D = ((6 << 3) + 6),
-  C_ULE_D = ((6 << 3) + 7),
+  ADD_D = ((0U << 3) + 0),
+  SUB_D = ((0U << 3) + 1),
+  MUL_D = ((0U << 3) + 2),
+  DIV_D = ((0U << 3) + 3),
+  SQRT_D = ((0U << 3) + 4),
+  ABS_D = ((0U << 3) + 5),
+  MOV_D = ((0U << 3) + 6),
+  NEG_D = ((0U << 3) + 7),
+  ROUND_L_D = ((1U << 3) + 0),
+  TRUNC_L_D = ((1U << 3) + 1),
+  CEIL_L_D = ((1U << 3) + 2),
+  FLOOR_L_D = ((1U << 3) + 3),
+  ROUND_W_D = ((1U << 3) + 4),
+  TRUNC_W_D = ((1U << 3) + 5),
+  CEIL_W_D = ((1U << 3) + 6),
+  FLOOR_W_D = ((1U << 3) + 7),
+  RECIP_D = ((2U << 3) + 5),
+  RSQRT_D = ((2U << 3) + 6),
+  CLASS_D = ((3U << 3) + 3),
+  MIN = ((3U << 3) + 4),
+  MINA = ((3U << 3) + 5),
+  MAX = ((3U << 3) + 6),
+  MAXA = ((3U << 3) + 7),
+  CVT_S_D = ((4U << 3) + 0),
+  CVT_W_D = ((4U << 3) + 4),
+  CVT_L_D = ((4U << 3) + 5),
+  C_F_D = ((6U << 3) + 0),
+  C_UN_D = ((6U << 3) + 1),
+  C_EQ_D = ((6U << 3) + 2),
+  C_UEQ_D = ((6U << 3) + 3),
+  C_OLT_D = ((6U << 3) + 4),
+  C_ULT_D = ((6U << 3) + 5),
+  C_OLE_D = ((6U << 3) + 6),
+  C_ULE_D = ((6U << 3) + 7),
 
   // COP1 Encoding of Function Field When rs=W or L.
-  CVT_S_W = ((4 << 3) + 0),
-  CVT_D_W = ((4 << 3) + 1),
-  CVT_S_L = ((4 << 3) + 0),
-  CVT_D_L = ((4 << 3) + 1),
-  BC1EQZ = ((2 << 2) + 1) << 21,
-  BC1NEZ = ((3 << 2) + 1) << 21,
+  CVT_S_W = ((4U << 3) + 0),
+  CVT_D_W = ((4U << 3) + 1),
+  CVT_S_L = ((4U << 3) + 0),
+  CVT_D_L = ((4U << 3) + 1),
+  BC1EQZ = ((2U << 2) + 1) << 21,
+  BC1NEZ = ((3U << 2) + 1) << 21,
   // COP1 CMP positive predicates Bit 5..4 = 00.
-  CMP_AF = ((0 << 3) + 0),
-  CMP_UN = ((0 << 3) + 1),
-  CMP_EQ = ((0 << 3) + 2),
-  CMP_UEQ = ((0 << 3) + 3),
-  CMP_LT = ((0 << 3) + 4),
-  CMP_ULT = ((0 << 3) + 5),
-  CMP_LE = ((0 << 3) + 6),
-  CMP_ULE = ((0 << 3) + 7),
-  CMP_SAF = ((1 << 3) + 0),
-  CMP_SUN = ((1 << 3) + 1),
-  CMP_SEQ = ((1 << 3) + 2),
-  CMP_SUEQ = ((1 << 3) + 3),
-  CMP_SSLT = ((1 << 3) + 4),
-  CMP_SSULT = ((1 << 3) + 5),
-  CMP_SLE = ((1 << 3) + 6),
-  CMP_SULE = ((1 << 3) + 7),
+  CMP_AF = ((0U << 3) + 0),
+  CMP_UN = ((0U << 3) + 1),
+  CMP_EQ = ((0U << 3) + 2),
+  CMP_UEQ = ((0U << 3) + 3),
+  CMP_LT = ((0U << 3) + 4),
+  CMP_ULT = ((0U << 3) + 5),
+  CMP_LE = ((0U << 3) + 6),
+  CMP_ULE = ((0U << 3) + 7),
+  CMP_SAF = ((1U << 3) + 0),
+  CMP_SUN = ((1U << 3) + 1),
+  CMP_SEQ = ((1U << 3) + 2),
+  CMP_SUEQ = ((1U << 3) + 3),
+  CMP_SSLT = ((1U << 3) + 4),
+  CMP_SSULT = ((1U << 3) + 5),
+  CMP_SLE = ((1U << 3) + 6),
+  CMP_SULE = ((1U << 3) + 7),
   // COP1 CMP negative predicates Bit 5..4 = 01.
-  CMP_AT = ((2 << 3) + 0),  // Reserved, not implemented.
-  CMP_OR = ((2 << 3) + 1),
-  CMP_UNE = ((2 << 3) + 2),
-  CMP_NE = ((2 << 3) + 3),
-  CMP_UGE = ((2 << 3) + 4),  // Reserved, not implemented.
-  CMP_OGE = ((2 << 3) + 5),  // Reserved, not implemented.
-  CMP_UGT = ((2 << 3) + 6),  // Reserved, not implemented.
-  CMP_OGT = ((2 << 3) + 7),  // Reserved, not implemented.
-  CMP_SAT = ((3 << 3) + 0),  // Reserved, not implemented.
-  CMP_SOR = ((3 << 3) + 1),
-  CMP_SUNE = ((3 << 3) + 2),
-  CMP_SNE = ((3 << 3) + 3),
-  CMP_SUGE = ((3 << 3) + 4),  // Reserved, not implemented.
-  CMP_SOGE = ((3 << 3) + 5),  // Reserved, not implemented.
-  CMP_SUGT = ((3 << 3) + 6),  // Reserved, not implemented.
-  CMP_SOGT = ((3 << 3) + 7),  // Reserved, not implemented.
-
-  SEL = ((2 << 3) + 0),
-  MOVZ_C = ((2 << 3) + 2),
-  MOVN_C = ((2 << 3) + 3),
-  SELEQZ_C = ((2 << 3) + 4),  // COP1 on FPR registers.
-  MOVF = ((2 << 3) + 1),      // Function field for MOVT.fmt and MOVF.fmt
-  SELNEZ_C = ((2 << 3) + 7),  // COP1 on FPR registers.
+  CMP_AT = ((2U << 3) + 0),  // Reserved, not implemented.
+  CMP_OR = ((2U << 3) + 1),
+  CMP_UNE = ((2U << 3) + 2),
+  CMP_NE = ((2U << 3) + 3),
+  CMP_UGE = ((2U << 3) + 4),  // Reserved, not implemented.
+  CMP_OGE = ((2U << 3) + 5),  // Reserved, not implemented.
+  CMP_UGT = ((2U << 3) + 6),  // Reserved, not implemented.
+  CMP_OGT = ((2U << 3) + 7),  // Reserved, not implemented.
+  CMP_SAT = ((3U << 3) + 0),  // Reserved, not implemented.
+  CMP_SOR = ((3U << 3) + 1),
+  CMP_SUNE = ((3U << 3) + 2),
+  CMP_SNE = ((3U << 3) + 3),
+  CMP_SUGE = ((3U << 3) + 4),  // Reserved, not implemented.
+  CMP_SOGE = ((3U << 3) + 5),  // Reserved, not implemented.
+  CMP_SUGT = ((3U << 3) + 6),  // Reserved, not implemented.
+  CMP_SOGT = ((3U << 3) + 7),  // Reserved, not implemented.
+
+  SEL = ((2U << 3) + 0),
+  MOVZ_C = ((2U << 3) + 2),
+  MOVN_C = ((2U << 3) + 3),
+  SELEQZ_C = ((2U << 3) + 4),  // COP1 on FPR registers.
+  MOVF = ((2U << 3) + 1),      // Function field for MOVT.fmt and MOVF.fmt
+  SELNEZ_C = ((2U << 3) + 7),  // COP1 on FPR registers.
   // COP1 Encoding of Function Field When rs=PS.
   // COP1X Encoding of Function Field.
-  MADD_D = ((4 << 3) + 1),
+  MADD_D = ((4U << 3) + 1),
 
   // PCREL Encoding of rt Field.
-  ADDIUPC = ((0 << 2) + 0),
-  LWPC = ((0 << 2) + 1),
-  AUIPC = ((3 << 3) + 6),
-  ALUIPC = ((3 << 3) + 7),
+  ADDIUPC = ((0U << 2) + 0),
+  LWPC = ((0U << 2) + 1),
+  AUIPC = ((3U << 3) + 6),
+  ALUIPC = ((3U << 3) + 7),
 
   // POP66 Encoding of rs Field.
-  JIC = ((0 << 5) + 0),
+  JIC = ((0U << 5) + 0),
 
   // POP76 Encoding of rs Field.
-  JIALC = ((0 << 5) + 0),
+  JIALC = ((0U << 5) + 0),
 
-  NULLSF = 0
+  NULLSF = 0U
 };
 
 
@@ -820,6 +828,10 @@ const Instr rtCallRedirInstr = SPECIAL | BREAK | call_rt_redirected << 6;
 // A nop instruction. (Encoding of sll 0 0 0).
 const Instr nopInstr = 0;
 
+static constexpr uint64_t OpcodeToBitNumber(Opcode opcode) {
+  return 1ULL << (static_cast<uint32_t>(opcode) >> kOpcodeShift);
+}
+
 
 class Instruction {
  public:
@@ -848,7 +860,7 @@ class Instruction {
 
   // Read a bit field out of the instruction bits.
   inline int Bits(int hi, int lo) const {
-    return (InstructionBits() >> lo) & ((2 << (hi - lo)) - 1);
+    return (InstructionBits() >> lo) & ((2U << (hi - lo)) - 1);
   }
 
   // Instruction type.
@@ -862,10 +874,7 @@ class Instruction {
   enum TypeChecks { NORMAL, EXTRA };
 
 
-#define OpcodeToBitNumber(opcode) \
-  (1ULL << (static_cast<uint32_t>(opcode) >> kOpcodeShift))
-
-  static const uint64_t kOpcodeImmediateTypeMask =
+  static constexpr uint64_t kOpcodeImmediateTypeMask =
       OpcodeToBitNumber(REGIMM) | OpcodeToBitNumber(BEQ) |
       OpcodeToBitNumber(BNE) | OpcodeToBitNumber(BLEZ) |
       OpcodeToBitNumber(BGTZ) | OpcodeToBitNumber(ADDI) |
@@ -1032,6 +1041,11 @@ class Instruction {
     }
   }
 
+  inline int32_t ImmValue(int bits) const {
+    DCHECK(InstructionType() == kImmediateType);
+    return Bits(bits - 1, 0);
+  }
+
   inline int32_t Imm16Value() const {
     DCHECK(InstructionType() == kImmediateType);
     return Bits(kImm16Shift + kImm16Bits - 1, kImm16Shift);
@@ -1058,8 +1072,18 @@ class Instruction {
     return Bits(kImm26Shift + kImm26Bits - 1, kImm26Shift);
   }
 
-  // Say if the instruction should not be used in a branch delay slot.
-  bool IsForbiddenInBranchDelay() const;
+  static bool IsForbiddenAfterBranchInstr(Instr instr);
+
+  // Say if the instruction should not be used in a branch delay slot or
+  // immediately after a compact branch.
+  inline bool IsForbiddenAfterBranch() const {
+    return IsForbiddenAfterBranchInstr(InstructionBits());
+  }
+
+  inline bool IsForbiddenInBranchDelay() const {
+    return IsForbiddenAfterBranch();
+  }
+
   // Say if the instruction 'links'. e.g. jal, bal.
   bool IsLinkingInstruction() const;
   // Say if the instruction is a break or a trap.