xref: /external/valgrind/main/VEX/priv/host_arm_defs.c

/*---------------------------------------------------------------*/
/*--- begin                                   host_arm_defs.c ---*/
/*---------------------------------------------------------------*/

/*
   This file is part of Valgrind, a dynamic binary instrumentation
   framework.

   Copyright (C) 2004-2013 OpenWorks LLP
      info@open-works.net

   NEON support is
   Copyright (C) 2010-2013 Samsung Electronics
   contributed by Dmitry Zhurikhin <zhur@ispras.ru>
              and Kirill Batuzov <batuzovk@ispras.ru>

   This program is free software; you can redistribute it and/or
   modify it under the terms of the GNU General Public License as
   published by the Free Software Foundation; either version 2 of the
   License, or (at your option) any later version.

   This program is distributed in the hope that it will be useful, but
   WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
   02110-1301, USA.

   The GNU General Public License is contained in the file COPYING.
*/

#include "libvex_basictypes.h"
#include "libvex.h"
#include "libvex_trc_values.h"

#include "main_util.h"
#include "host_generic_regs.h"
#include "host_arm_defs.h"

UInt arm_hwcaps = 0;


/* --------- Registers. --------- */

/* The usual HReg abstraction.
   There are 16 general purpose regs.
*/

void ppHRegARM ( HReg reg )  {
   Int r;
   /* Be generic for all virtual regs. */
   if (hregIsVirtual(reg)) {
      ppHReg(reg);
      return;
   }
   /* But specific for real regs. */
   switch (hregClass(reg)) {
      case HRcInt32:
         r = hregNumber(reg);
         vassert(r >= 0 && r < 16);
         vex_printf("r%d", r);
         return;
      case HRcFlt64:
         r = hregNumber(reg);
         vassert(r >= 0 && r < 32);
         vex_printf("d%d", r);
         return;
      case HRcFlt32:
         r = hregNumber(reg);
         vassert(r >= 0 && r < 32);
         vex_printf("s%d", r);
         return;
      case HRcVec128:
         r = hregNumber(reg);
         vassert(r >= 0 && r < 16);
         vex_printf("q%d", r);
         return;
      default:
         vpanic("ppHRegARM");
   }
}

HReg hregARM_R0  ( void ) { return mkHReg(0,  HRcInt32, False); }
HReg hregARM_R1  ( void ) { return mkHReg(1,  HRcInt32, False); }
HReg hregARM_R2  ( void ) { return mkHReg(2,  HRcInt32, False); }
HReg hregARM_R3  ( void ) { return mkHReg(3,  HRcInt32, False); }
HReg hregARM_R4  ( void ) { return mkHReg(4,  HRcInt32, False); }
HReg hregARM_R5  ( void ) { return mkHReg(5,  HRcInt32, False); }
HReg hregARM_R6  ( void ) { return mkHReg(6,  HRcInt32, False); }
HReg hregARM_R7  ( void ) { return mkHReg(7,  HRcInt32, False); }
HReg hregARM_R8  ( void ) { return mkHReg(8,  HRcInt32, False); }
HReg hregARM_R9  ( void ) { return mkHReg(9,  HRcInt32, False); }
HReg hregARM_R10 ( void ) { return mkHReg(10, HRcInt32, False); }
HReg hregARM_R11 ( void ) { return mkHReg(11, HRcInt32, False); }
HReg hregARM_R12 ( void ) { return mkHReg(12, HRcInt32, False); }
HReg hregARM_R13 ( void ) { return mkHReg(13, HRcInt32, False); }
HReg hregARM_R14 ( void ) { return mkHReg(14, HRcInt32, False); }
HReg hregARM_R15 ( void ) { return mkHReg(15, HRcInt32, False); }
HReg hregARM_D8  ( void ) { return mkHReg(8,  HRcFlt64, False); }
HReg hregARM_D9  ( void ) { return mkHReg(9,  HRcFlt64, False); }
HReg hregARM_D10 ( void ) { return mkHReg(10, HRcFlt64, False); }
HReg hregARM_D11 ( void ) { return mkHReg(11, HRcFlt64, False); }
HReg hregARM_D12 ( void ) { return mkHReg(12, HRcFlt64, False); }
HReg hregARM_S26 ( void ) { return mkHReg(26, HRcFlt32, False); }
HReg hregARM_S27 ( void ) { return mkHReg(27, HRcFlt32, False); }
HReg hregARM_S28 ( void ) { return mkHReg(28, HRcFlt32, False); }
HReg hregARM_S29 ( void ) { return mkHReg(29, HRcFlt32, False); }
HReg hregARM_S30 ( void ) { return mkHReg(30, HRcFlt32, False); }
HReg hregARM_Q8  ( void ) { return mkHReg(8,  HRcVec128, False); }
HReg hregARM_Q9  ( void ) { return mkHReg(9,  HRcVec128, False); }
HReg hregARM_Q10 ( void ) { return mkHReg(10, HRcVec128, False); }
HReg hregARM_Q11 ( void ) { return mkHReg(11, HRcVec128, False); }
HReg hregARM_Q12 ( void ) { return mkHReg(12, HRcVec128, False); }
HReg hregARM_Q13 ( void ) { return mkHReg(13, HRcVec128, False); }
HReg hregARM_Q14 ( void ) { return mkHReg(14, HRcVec128, False); }
HReg hregARM_Q15 ( void ) { return mkHReg(15, HRcVec128, False); }

void getAllocableRegs_ARM ( Int* nregs, HReg** arr )
{
   Int i = 0;
   *nregs = 26;
   *arr = LibVEX_Alloc(*nregs * sizeof(HReg));
   // callee saves ones are listed first, since we prefer them
   // if they're available
   (*arr)[i++] = hregARM_R4();
   (*arr)[i++] = hregARM_R5();
   (*arr)[i++] = hregARM_R6();
   (*arr)[i++] = hregARM_R7();
   (*arr)[i++] = hregARM_R10();
   (*arr)[i++] = hregARM_R11();
   // otherwise we'll have to slum it out with caller-saves ones
   (*arr)[i++] = hregARM_R0();
   (*arr)[i++] = hregARM_R1();
   (*arr)[i++] = hregARM_R2();
   (*arr)[i++] = hregARM_R3();
   (*arr)[i++] = hregARM_R9();
   // FP hreegisters.  Note: these are all callee-save.  Yay!
   // Hence we don't need to mention them as trashed in
   // getHRegUsage for ARMInstr_Call.
   (*arr)[i++] = hregARM_D8();
   (*arr)[i++] = hregARM_D9();
   (*arr)[i++] = hregARM_D10();
   (*arr)[i++] = hregARM_D11();
   (*arr)[i++] = hregARM_D12();
   (*arr)[i++] = hregARM_S26();
   (*arr)[i++] = hregARM_S27();
   (*arr)[i++] = hregARM_S28();
   (*arr)[i++] = hregARM_S29();
   (*arr)[i++] = hregARM_S30();

   (*arr)[i++] = hregARM_Q8();
   (*arr)[i++] = hregARM_Q9();
   (*arr)[i++] = hregARM_Q10();
   (*arr)[i++] = hregARM_Q11();
   (*arr)[i++] = hregARM_Q12();

   //(*arr)[i++] = hregARM_Q13();
   //(*arr)[i++] = hregARM_Q14();
   //(*arr)[i++] = hregARM_Q15();

   // unavail: r8 as GSP
   // r12 is used as a spill/reload temporary
   // r13 as SP
   // r14 as LR
   // r15 as PC
   //
   // All in all, we have 11 allocatable integer registers:
   // 0 1 2 3 4 5 6 7 9 10 11, with r8 dedicated as GSP
   // and r12 dedicated as a spill temporary.
   // 13 14 and 15 are not under the allocator's control.
   //
   // Hence for the allocatable registers we have:
   //
   // callee-saved: 4 5 6 7 (8) 9 10 11
   // caller-saved: 0 1 2 3
   // Note 9 is ambiguous: the base EABI does not give an e/r-saved
   // designation for it, but the Linux instantiation of the ABI
   // specifies it as callee-saved.
   //
   // If the set of available registers changes or if the e/r status
   // changes, be sure to re-check/sync the definition of
   // getHRegUsage for ARMInstr_Call too.
   vassert(i == *nregs);
}



/* --------- Condition codes, ARM encoding. --------- */

const HChar* showARMCondCode ( ARMCondCode cond ) {
   switch (cond) {
       case ARMcc_EQ:  return "eq";
       case ARMcc_NE:  return "ne";
       case ARMcc_HS:  return "hs";
       case ARMcc_LO:  return "lo";
       case ARMcc_MI:  return "mi";
       case ARMcc_PL:  return "pl";
       case ARMcc_VS:  return "vs";
       case ARMcc_VC:  return "vc";
       case ARMcc_HI:  return "hi";
       case ARMcc_LS:  return "ls";
       case ARMcc_GE:  return "ge";
       case ARMcc_LT:  return "lt";
       case ARMcc_GT:  return "gt";
       case ARMcc_LE:  return "le";
       case ARMcc_AL:  return "al"; // default
       case ARMcc_NV:  return "nv";
       default: vpanic("showARMCondCode");
   }
}


/* --------- Mem AModes: Addressing Mode 1 --------- */

ARMAMode1* ARMAMode1_RI  ( HReg reg, Int simm13 ) {
   ARMAMode1* am        = LibVEX_Alloc(sizeof(ARMAMode1));
   am->tag              = ARMam1_RI;
   am->ARMam1.RI.reg    = reg;
   am->ARMam1.RI.simm13 = simm13;
   vassert(-4095 <= simm13 && simm13 <= 4095);
   return am;
}
ARMAMode1* ARMAMode1_RRS ( HReg base, HReg index, UInt shift ) {
   ARMAMode1* am        = LibVEX_Alloc(sizeof(ARMAMode1));
   am->tag              = ARMam1_RRS;
   am->ARMam1.RRS.base  = base;
   am->ARMam1.RRS.index = index;
   am->ARMam1.RRS.shift = shift;
   vassert(0 <= shift && shift <= 3);
   return am;
}

void ppARMAMode1 ( ARMAMode1* am ) {
   switch (am->tag) {
      case ARMam1_RI:
         vex_printf("%d(", am->ARMam1.RI.simm13);
         ppHRegARM(am->ARMam1.RI.reg);
         vex_printf(")");
         break;
      case ARMam1_RRS:
         vex_printf("(");
         ppHRegARM(am->ARMam1.RRS.base);
         vex_printf(",");
         ppHRegARM(am->ARMam1.RRS.index);
         vex_printf(",%u)", am->ARMam1.RRS.shift);
         break;
      default:
         vassert(0);
   }
}

static void addRegUsage_ARMAMode1 ( HRegUsage* u, ARMAMode1* am ) {
   switch (am->tag) {
      case ARMam1_RI:
         addHRegUse(u, HRmRead, am->ARMam1.RI.reg);
         return;
      case ARMam1_RRS:
         //    addHRegUse(u, HRmRead, am->ARMam1.RRS.base);
         //    addHRegUse(u, HRmRead, am->ARMam1.RRS.index);
         //   return;
      default:
         vpanic("addRegUsage_ARMAmode1");
   }
}

static void mapRegs_ARMAMode1 ( HRegRemap* m, ARMAMode1* am ) {
   switch (am->tag) {
      case ARMam1_RI:
         am->ARMam1.RI.reg = lookupHRegRemap(m, am->ARMam1.RI.reg);
         return;
      case ARMam1_RRS:
         //am->ARMam1.RR.base =lookupHRegRemap(m, am->ARMam1.RR.base);
         //am->ARMam1.RR.index = lookupHRegRemap(m, am->ARMam1.RR.index);
         //return;
      default:
         vpanic("mapRegs_ARMAmode1");
   }
}


/* --------- Mem AModes: Addressing Mode 2 --------- */

ARMAMode2* ARMAMode2_RI ( HReg reg, Int simm9 ) {
   ARMAMode2* am       = LibVEX_Alloc(sizeof(ARMAMode2));
   am->tag             = ARMam2_RI;
   am->ARMam2.RI.reg   = reg;
   am->ARMam2.RI.simm9 = simm9;
   vassert(-255 <= simm9 && simm9 <= 255);
   return am;
}
ARMAMode2* ARMAMode2_RR ( HReg base, HReg index ) {
   ARMAMode2* am       = LibVEX_Alloc(sizeof(ARMAMode2));
   am->tag             = ARMam2_RR;
   am->ARMam2.RR.base  = base;
   am->ARMam2.RR.index = index;
   return am;
}

void ppARMAMode2 ( ARMAMode2* am ) {
   switch (am->tag) {
      case ARMam2_RI:
         vex_printf("%d(", am->ARMam2.RI.simm9);
         ppHRegARM(am->ARMam2.RI.reg);
         vex_printf(")");
         break;
      case ARMam2_RR:
         vex_printf("(");
         ppHRegARM(am->ARMam2.RR.base);
         vex_printf(",");
         ppHRegARM(am->ARMam2.RR.index);
         vex_printf(")");
         break;
      default:
         vassert(0);
   }
}

static void addRegUsage_ARMAMode2 ( HRegUsage* u, ARMAMode2* am ) {
   switch (am->tag) {
      case ARMam2_RI:
         addHRegUse(u, HRmRead, am->ARMam2.RI.reg);
         return;
      case ARMam2_RR:
         //    addHRegUse(u, HRmRead, am->ARMam2.RR.base);
         //    addHRegUse(u, HRmRead, am->ARMam2.RR.index);
         //   return;
      default:
         vpanic("addRegUsage_ARMAmode2");
   }
}

static void mapRegs_ARMAMode2 ( HRegRemap* m, ARMAMode2* am ) {
   switch (am->tag) {
      case ARMam2_RI:
         am->ARMam2.RI.reg = lookupHRegRemap(m, am->ARMam2.RI.reg);
         return;
      case ARMam2_RR:
         //am->ARMam2.RR.base =lookupHRegRemap(m, am->ARMam2.RR.base);
         //am->ARMam2.RR.index = lookupHRegRemap(m, am->ARMam2.RR.index);
         //return;
      default:
         vpanic("mapRegs_ARMAmode2");
   }
}


/* --------- Mem AModes: Addressing Mode VFP --------- */

ARMAModeV* mkARMAModeV ( HReg reg, Int simm11 ) {
   ARMAModeV* am = LibVEX_Alloc(sizeof(ARMAModeV));
   vassert(simm11 >= -1020 && simm11 <= 1020);
   vassert(0 == (simm11 & 3));
   am->reg    = reg;
   am->simm11 = simm11;
   return am;
}

void ppARMAModeV ( ARMAModeV* am ) {
   vex_printf("%d(", am->simm11);
   ppHRegARM(am->reg);
   vex_printf(")");
}

static void addRegUsage_ARMAModeV ( HRegUsage* u, ARMAModeV* am ) {
   addHRegUse(u, HRmRead, am->reg);
}

static void mapRegs_ARMAModeV ( HRegRemap* m, ARMAModeV* am ) {
   am->reg = lookupHRegRemap(m, am->reg);
}


/* --------- Mem AModes: Addressing Mode Neon ------- */

ARMAModeN *mkARMAModeN_RR ( HReg rN, HReg rM ) {
   ARMAModeN* am = LibVEX_Alloc(sizeof(ARMAModeN));
   am->tag = ARMamN_RR;
   am->ARMamN.RR.rN = rN;
   am->ARMamN.RR.rM = rM;
   return am;
}

ARMAModeN *mkARMAModeN_R ( HReg rN ) {
   ARMAModeN* am = LibVEX_Alloc(sizeof(ARMAModeN));
   am->tag = ARMamN_R;
   am->ARMamN.R.rN = rN;
   return am;
}

static void addRegUsage_ARMAModeN ( HRegUsage* u, ARMAModeN* am ) {
   if (am->tag == ARMamN_R) {
      addHRegUse(u, HRmRead, am->ARMamN.R.rN);
   } else {
      addHRegUse(u, HRmRead, am->ARMamN.RR.rN);
      addHRegUse(u, HRmRead, am->ARMamN.RR.rM);
   }
}

static void mapRegs_ARMAModeN ( HRegRemap* m, ARMAModeN* am ) {
   if (am->tag == ARMamN_R) {
      am->ARMamN.R.rN = lookupHRegRemap(m, am->ARMamN.R.rN);
   } else {
      am->ARMamN.RR.rN = lookupHRegRemap(m, am->ARMamN.RR.rN);
      am->ARMamN.RR.rM = lookupHRegRemap(m, am->ARMamN.RR.rM);
   }
}

void ppARMAModeN ( ARMAModeN* am ) {
   vex_printf("[");
   if (am->tag == ARMamN_R) {
      ppHRegARM(am->ARMamN.R.rN);
   } else {
      ppHRegARM(am->ARMamN.RR.rN);
   }
   vex_printf("]");
   if (am->tag == ARMamN_RR) {
      vex_printf(", ");
      ppHRegARM(am->ARMamN.RR.rM);
   }
}


/* --------- Reg or imm-8x4 operands --------- */

static UInt ROR32 ( UInt x, UInt sh ) {
   vassert(sh >= 0 && sh < 32);
   if (sh == 0)
      return x;
   else
      return (x << (32-sh)) | (x >> sh);
}

ARMRI84* ARMRI84_I84 ( UShort imm8, UShort imm4 ) {
   ARMRI84* ri84          = LibVEX_Alloc(sizeof(ARMRI84));
   ri84->tag              = ARMri84_I84;
   ri84->ARMri84.I84.imm8 = imm8;
   ri84->ARMri84.I84.imm4 = imm4;
   vassert(imm8 >= 0 && imm8 <= 255);
   vassert(imm4 >= 0 && imm4 <= 15);
   return ri84;
}
ARMRI84* ARMRI84_R ( HReg reg ) {
   ARMRI84* ri84       = LibVEX_Alloc(sizeof(ARMRI84));
   ri84->tag           = ARMri84_R;
   ri84->ARMri84.R.reg = reg;
   return ri84;
}

void ppARMRI84 ( ARMRI84* ri84 ) {
   switch (ri84->tag) {
      case ARMri84_I84:
         vex_printf("0x%x", ROR32(ri84->ARMri84.I84.imm8,
                                  2 * ri84->ARMri84.I84.imm4));
         break;
      case ARMri84_R:
         ppHRegARM(ri84->ARMri84.R.reg);
         break;
      default:
         vassert(0);
   }
}

static void addRegUsage_ARMRI84 ( HRegUsage* u, ARMRI84* ri84 ) {
   switch (ri84->tag) {
      case ARMri84_I84:
         return;
      case ARMri84_R:
         addHRegUse(u, HRmRead, ri84->ARMri84.R.reg);
         return;
      default:
         vpanic("addRegUsage_ARMRI84");
   }
}

static void mapRegs_ARMRI84 ( HRegRemap* m, ARMRI84* ri84 ) {
   switch (ri84->tag) {
      case ARMri84_I84:
         return;
      case ARMri84_R:
         ri84->ARMri84.R.reg = lookupHRegRemap(m, ri84->ARMri84.R.reg);
         return;
      default:
         vpanic("mapRegs_ARMRI84");
   }
}


/* --------- Reg or imm5 operands --------- */

ARMRI5* ARMRI5_I5 ( UInt imm5 ) {
   ARMRI5* ri5         = LibVEX_Alloc(sizeof(ARMRI5));
   ri5->tag            = ARMri5_I5;
   ri5->ARMri5.I5.imm5 = imm5;
   vassert(imm5 > 0 && imm5 <= 31); // zero is not allowed
   return ri5;
}
ARMRI5* ARMRI5_R ( HReg reg ) {
   ARMRI5* ri5       = LibVEX_Alloc(sizeof(ARMRI5));
   ri5->tag          = ARMri5_R;
   ri5->ARMri5.R.reg = reg;
   return ri5;
}

void ppARMRI5 ( ARMRI5* ri5 ) {
   switch (ri5->tag) {
      case ARMri5_I5:
         vex_printf("%u", ri5->ARMri5.I5.imm5);
         break;
      case ARMri5_R:
         ppHRegARM(ri5->ARMri5.R.reg);
         break;
      default:
         vassert(0);
   }
}

static void addRegUsage_ARMRI5 ( HRegUsage* u, ARMRI5* ri5 ) {
   switch (ri5->tag) {
      case ARMri5_I5:
         return;
      case ARMri5_R:
         addHRegUse(u, HRmRead, ri5->ARMri5.R.reg);
         return;
      default:
         vpanic("addRegUsage_ARMRI5");
   }
}

static void mapRegs_ARMRI5 ( HRegRemap* m, ARMRI5* ri5 ) {
   switch (ri5->tag) {
      case ARMri5_I5:
         return;
      case ARMri5_R:
         ri5->ARMri5.R.reg = lookupHRegRemap(m, ri5->ARMri5.R.reg);
         return;
      default:
         vpanic("mapRegs_ARMRI5");
   }
}

/* -------- Neon Immediate operatnd --------- */

ARMNImm* ARMNImm_TI ( UInt type, UInt imm8 ) {
   ARMNImm* i = LibVEX_Alloc(sizeof(ARMNImm));
   i->type = type;
   i->imm8 = imm8;
   return i;
}

ULong ARMNImm_to_Imm64 ( ARMNImm* imm ) {
   int i, j;
   ULong y, x = imm->imm8;
   switch (imm->type) {
      case 3:
         x = x << 8; /* fallthrough */
      case 2:
         x = x << 8; /* fallthrough */
      case 1:
         x = x << 8; /* fallthrough */
      case 0:
         return (x << 32) | x;
      case 5:
      case 6:
         if (imm->type == 5)
            x = x << 8;
         else
            x = (x << 8) | x;
         /* fallthrough */
      case 4:
         x = (x << 16) | x;
         return (x << 32) | x;
      case 8:
         x = (x << 8) | 0xFF;
         /* fallthrough */
      case 7:
         x = (x << 8) | 0xFF;
         return (x << 32) | x;
      case 9:
         x = 0;
         for (i = 7; i >= 0; i--) {
            y = ((ULong)imm->imm8 >> i) & 1;
            for (j = 0; j < 8; j++) {
               x = (x << 1) | y;
            }
         }
         return x;
      case 10:
         x |= (x & 0x80) << 5;
         x |= (~x & 0x40) << 5;
         x &= 0x187F; /* 0001 1000 0111 1111 */
         x |= (x & 0x40) << 4;
         x |= (x & 0x40) << 3;
         x |= (x & 0x40) << 2;
         x |= (x & 0x40) << 1;
         x = x << 19;
         x = (x << 32) | x;
         return x;
      default:
         vpanic("ARMNImm_to_Imm64");
   }
}

ARMNImm* Imm64_to_ARMNImm ( ULong x ) {
   ARMNImm tmp;
   if ((x & 0xFFFFFFFF) == (x >> 32)) {
      if ((x & 0xFFFFFF00) == 0)
         return ARMNImm_TI(0, x & 0xFF);
      if ((x & 0xFFFF00FF) == 0)
         return ARMNImm_TI(1, (x >> 8) & 0xFF);
      if ((x & 0xFF00FFFF) == 0)
         return ARMNImm_TI(2, (x >> 16) & 0xFF);
      if ((x & 0x00FFFFFF) == 0)
         return ARMNImm_TI(3, (x >> 24) & 0xFF);
      if ((x & 0xFFFF00FF) == 0xFF)
         return ARMNImm_TI(7, (x >> 8) & 0xFF);
      if ((x & 0xFF00FFFF) == 0xFFFF)
         return ARMNImm_TI(8, (x >> 16) & 0xFF);
      if ((x & 0xFFFF) == ((x >> 16) & 0xFFFF)) {
         if ((x & 0xFF00) == 0)
            return ARMNImm_TI(4, x & 0xFF);
         if ((x & 0x00FF) == 0)
            return ARMNImm_TI(5, (x >> 8) & 0xFF);
         if ((x & 0xFF) == ((x >> 8) & 0xFF))
            return ARMNImm_TI(6, x & 0xFF);
      }
      if ((x & 0x7FFFF) == 0) {
         tmp.type = 10;
         tmp.imm8 = ((x >> 19) & 0x7F) | ((x >> 24) & 0x80);
         if (ARMNImm_to_Imm64(&tmp) == x)
            return ARMNImm_TI(tmp.type, tmp.imm8);
      }
   } else {
      /* This can only be type 9. */
      tmp.imm8 = (((x >> 56) & 1) << 7)
               | (((x >> 48) & 1) << 6)
               | (((x >> 40) & 1) << 5)
               | (((x >> 32) & 1) << 4)
               | (((x >> 24) & 1) << 3)
               | (((x >> 16) & 1) << 2)
               | (((x >>  8) & 1) << 1)
               | (((x >>  0) & 1) << 0);
      tmp.type = 9;
      if (ARMNImm_to_Imm64 (&tmp) == x)
         return ARMNImm_TI(tmp.type, tmp.imm8);
   }
   return NULL;
}

void ppARMNImm (ARMNImm* i) {
   ULong x = ARMNImm_to_Imm64(i);
   vex_printf("0x%llX%llX", x, x);
}

/* -- Register or scalar operand --- */

ARMNRS* mkARMNRS(ARMNRS_tag tag, HReg reg, UInt index)
{
   ARMNRS *p = LibVEX_Alloc(sizeof(ARMNRS));
   p->tag = tag;
   p->reg = reg;
   p->index = index;
   return p;
}

void ppARMNRS(ARMNRS *p)
{
   ppHRegARM(p->reg);
   if (p->tag == ARMNRS_Scalar) {
      vex_printf("[%d]", p->index);
   }
}

/* --------- Instructions. --------- */

const HChar* showARMAluOp ( ARMAluOp op ) {
   switch (op) {
      case ARMalu_ADD:  return "add";
      case ARMalu_ADDS: return "adds";
      case ARMalu_ADC:  return "adc";
      case ARMalu_SUB:  return "sub";
      case ARMalu_SUBS: return "subs";
      case ARMalu_SBC:  return "sbc";
      case ARMalu_AND:  return "and";
      case ARMalu_BIC:  return "bic";
      case ARMalu_OR:   return "orr";
      case ARMalu_XOR:  return "xor";
      default: vpanic("showARMAluOp");
   }
}

const HChar* showARMShiftOp ( ARMShiftOp op ) {
   switch (op) {
      case ARMsh_SHL: return "shl";
      case ARMsh_SHR: return "shr";
      case ARMsh_SAR: return "sar";
      default: vpanic("showARMShiftOp");
   }
}

const HChar* showARMUnaryOp ( ARMUnaryOp op ) {
   switch (op) {
      case ARMun_NEG: return "neg";
      case ARMun_NOT: return "not";
      case ARMun_CLZ: return "clz";
      default: vpanic("showARMUnaryOp");
   }
}

const HChar* showARMMulOp ( ARMMulOp op ) {
   switch (op) {
      case ARMmul_PLAIN: return "mul";
      case ARMmul_ZX:    return "umull";
      case ARMmul_SX:    return "smull";
      default: vpanic("showARMMulOp");
   }
}

const HChar* showARMVfpOp ( ARMVfpOp op ) {
   switch (op) {
      case ARMvfp_ADD: return "add";
      case ARMvfp_SUB: return "sub";
      case ARMvfp_MUL: return "mul";
      case ARMvfp_DIV: return "div";
      default: vpanic("showARMVfpOp");
   }
}

const HChar* showARMVfpUnaryOp ( ARMVfpUnaryOp op ) {
   switch (op) {
      case ARMvfpu_COPY: return "cpy";
      case ARMvfpu_NEG:  return "neg";
      case ARMvfpu_ABS:  return "abs";
      case ARMvfpu_SQRT: return "sqrt";
      default: vpanic("showARMVfpUnaryOp");
   }
}

const HChar* showARMNeonBinOp ( ARMNeonBinOp op ) {
   switch (op) {
      case ARMneon_VAND: return "vand";
      case ARMneon_VORR: return "vorr";
      case ARMneon_VXOR: return "veor";
      case ARMneon_VADD: return "vadd";
      case ARMneon_VRHADDS: return "vrhadd";
      case ARMneon_VRHADDU: return "vrhadd";
      case ARMneon_VADDFP: return "vadd";
      case ARMneon_VPADDFP: return "vpadd";
      case ARMneon_VABDFP: return "vabd";
      case ARMneon_VSUB: return "vsub";
      case ARMneon_VSUBFP: return "vsub";
      case ARMneon_VMINU: return "vmin";
      case ARMneon_VMINS: return "vmin";
      case ARMneon_VMINF: return "vmin";
      case ARMneon_VMAXU: return "vmax";
      case ARMneon_VMAXS: return "vmax";
      case ARMneon_VMAXF: return "vmax";
      case ARMneon_VQADDU: return "vqadd";
      case ARMneon_VQADDS: return "vqadd";
      case ARMneon_VQSUBU: return "vqsub";
      case ARMneon_VQSUBS: return "vqsub";
      case ARMneon_VCGTU:  return "vcgt";
      case ARMneon_VCGTS:  return "vcgt";
      case ARMneon_VCGTF:  return "vcgt";
      case ARMneon_VCGEF:  return "vcgt";
      case ARMneon_VCGEU:  return "vcge";
      case ARMneon_VCGES:  return "vcge";
      case ARMneon_VCEQ:  return "vceq";
      case ARMneon_VCEQF:  return "vceq";
      case ARMneon_VPADD:   return "vpadd";
      case ARMneon_VPMINU:   return "vpmin";
      case ARMneon_VPMINS:   return "vpmin";
      case ARMneon_VPMINF:   return "vpmin";
      case ARMneon_VPMAXU:   return "vpmax";
      case ARMneon_VPMAXS:   return "vpmax";
      case ARMneon_VPMAXF:   return "vpmax";
      case ARMneon_VEXT:   return "vext";
      case ARMneon_VMUL:   return "vmuli";
      case ARMneon_VMULLU:   return "vmull";
      case ARMneon_VMULLS:   return "vmull";
      case ARMneon_VMULP:  return "vmul";
      case ARMneon_VMULFP:  return "vmul";
      case ARMneon_VMULLP:  return "vmul";
      case ARMneon_VQDMULH: return "vqdmulh";
      case ARMneon_VQRDMULH: return "vqrdmulh";
      case ARMneon_VQDMULL: return "vqdmull";
      case ARMneon_VTBL: return "vtbl";
      case ARMneon_VRECPS: return "vrecps";
      case ARMneon_VRSQRTS: return "vrecps";
      case ARMneon_INVALID: return "??invalid??";
      /* ... */
      default: vpanic("showARMNeonBinOp");
   }
}

const HChar* showARMNeonBinOpDataType ( ARMNeonBinOp op ) {
   switch (op) {
      case ARMneon_VAND:
      case ARMneon_VORR:
      case ARMneon_VXOR:
         return "";
      case ARMneon_VADD:
      case ARMneon_VSUB:
      case ARMneon_VEXT:
      case ARMneon_VMUL:
      case ARMneon_VPADD:
      case ARMneon_VTBL:
      case ARMneon_VCEQ:
         return ".i";
      case ARMneon_VRHADDU:
      case ARMneon_VMINU:
      case ARMneon_VMAXU:
      case ARMneon_VQADDU:
      case ARMneon_VQSUBU:
      case ARMneon_VCGTU:
      case ARMneon_VCGEU:
      case ARMneon_VMULLU:
      case ARMneon_VPMINU:
      case ARMneon_VPMAXU:
         return ".u";
      case ARMneon_VRHADDS:
      case ARMneon_VMINS:
      case ARMneon_VMAXS:
      case ARMneon_VQADDS:
      case ARMneon_VQSUBS:
      case ARMneon_VCGTS:
      case ARMneon_VCGES:
      case ARMneon_VQDMULL:
      case ARMneon_VMULLS:
      case ARMneon_VPMINS:
      case ARMneon_VPMAXS:
      case ARMneon_VQDMULH:
      case ARMneon_VQRDMULH:
         return ".s";
      case ARMneon_VMULP:
      case ARMneon_VMULLP:
         return ".p";
      case ARMneon_VADDFP:
      case ARMneon_VABDFP:
      case ARMneon_VPADDFP:
      case ARMneon_VSUBFP:
      case ARMneon_VMULFP:
      case ARMneon_VMINF:
      case ARMneon_VMAXF:
      case ARMneon_VPMINF:
      case ARMneon_VPMAXF:
      case ARMneon_VCGTF:
      case ARMneon_VCGEF:
      case ARMneon_VCEQF:
      case ARMneon_VRECPS:
      case ARMneon_VRSQRTS:
         return ".f";
      /* ... */
      default: vpanic("showARMNeonBinOpDataType");
   }
}

const HChar* showARMNeonUnOp ( ARMNeonUnOp op ) {
   switch (op) {
      case ARMneon_COPY: return "vmov";
      case ARMneon_COPYLS: return "vmov";
      case ARMneon_COPYLU: return "vmov";
      case ARMneon_COPYN: return "vmov";
      case ARMneon_COPYQNSS: return "vqmovn";
      case ARMneon_COPYQNUS: return "vqmovun";
      case ARMneon_COPYQNUU: return "vqmovn";
      case ARMneon_NOT: return "vmvn";
      case ARMneon_EQZ: return "vceq";
      case ARMneon_CNT: return "vcnt";
      case ARMneon_CLS: return "vcls";
      case ARMneon_CLZ: return "vclz";
      case ARMneon_DUP: return "vdup";
      case ARMneon_PADDLS: return "vpaddl";
      case ARMneon_PADDLU: return "vpaddl";
      case ARMneon_VQSHLNSS: return "vqshl";
      case ARMneon_VQSHLNUU: return "vqshl";
      case ARMneon_VQSHLNUS: return "vqshlu";
      case ARMneon_REV16: return "vrev16";
      case ARMneon_REV32: return "vrev32";
      case ARMneon_REV64: return "vrev64";
      case ARMneon_VCVTFtoU: return "vcvt";
      case ARMneon_VCVTFtoS: return "vcvt";
      case ARMneon_VCVTUtoF: return "vcvt";
      case ARMneon_VCVTStoF: return "vcvt";
      case ARMneon_VCVTFtoFixedU: return "vcvt";
      case ARMneon_VCVTFtoFixedS: return "vcvt";
      case ARMneon_VCVTFixedUtoF: return "vcvt";
      case ARMneon_VCVTFixedStoF: return "vcvt";
      case ARMneon_VCVTF32toF16: return "vcvt";
      case ARMneon_VCVTF16toF32: return "vcvt";
      case ARMneon_VRECIP: return "vrecip";
      case ARMneon_VRECIPF: return "vrecipf";
      case ARMneon_VNEGF: return "vneg";
      case ARMneon_ABS: return "vabs";
      case ARMneon_VABSFP: return "vabsfp";
      case ARMneon_VRSQRTEFP: return "vrsqrtefp";
      case ARMneon_VRSQRTE: return "vrsqrte";
      /* ... */
      default: vpanic("showARMNeonUnOp");
   }
}

const HChar* showARMNeonUnOpDataType ( ARMNeonUnOp op ) {
   switch (op) {
      case ARMneon_COPY:
      case ARMneon_NOT:
         return "";
      case ARMneon_COPYN:
      case ARMneon_EQZ:
      case ARMneon_CNT:
      case ARMneon_DUP:
      case ARMneon_REV16:
      case ARMneon_REV32:
      case ARMneon_REV64:
         return ".i";
      case ARMneon_COPYLU:
      case ARMneon_PADDLU:
      case ARMneon_COPYQNUU:
      case ARMneon_VQSHLNUU:
      case ARMneon_VRECIP:
      case ARMneon_VRSQRTE:
         return ".u";
      case ARMneon_CLS:
      case ARMneon_CLZ:
      case ARMneon_COPYLS:
      case ARMneon_PADDLS:
      case ARMneon_COPYQNSS:
      case ARMneon_COPYQNUS:
      case ARMneon_VQSHLNSS:
      case ARMneon_VQSHLNUS:
      case ARMneon_ABS:
         return ".s";
      case ARMneon_VRECIPF:
      case ARMneon_VNEGF:
      case ARMneon_VABSFP:
      case ARMneon_VRSQRTEFP:
         return ".f";
      case ARMneon_VCVTFtoU: return ".u32.f32";
      case ARMneon_VCVTFtoS: return ".s32.f32";
      case ARMneon_VCVTUtoF: return ".f32.u32";
      case ARMneon_VCVTStoF: return ".f32.s32";
      case ARMneon_VCVTF16toF32: return ".f32.f16";
      case ARMneon_VCVTF32toF16: return ".f16.f32";
      case ARMneon_VCVTFtoFixedU: return ".u32.f32";
      case ARMneon_VCVTFtoFixedS: return ".s32.f32";
      case ARMneon_VCVTFixedUtoF: return ".f32.u32";
      case ARMneon_VCVTFixedStoF: return ".f32.s32";
      /* ... */
      default: vpanic("showARMNeonUnOpDataType");
   }
}

const HChar* showARMNeonUnOpS ( ARMNeonUnOpS op ) {
   switch (op) {
      case ARMneon_SETELEM: return "vmov";
      case ARMneon_GETELEMU: return "vmov";
      case ARMneon_GETELEMS: return "vmov";
      case ARMneon_VDUP: return "vdup";
      /* ... */
      default: vpanic("showARMNeonUnarySOp");
   }
}

const HChar* showARMNeonUnOpSDataType ( ARMNeonUnOpS op ) {
   switch (op) {
      case ARMneon_SETELEM:
      case ARMneon_VDUP:
         return ".i";
      case ARMneon_GETELEMS:
         return ".s";
      case ARMneon_GETELEMU:
         return ".u";
      /* ... */
      default: vpanic("showARMNeonUnarySOp");
   }
}

const HChar* showARMNeonShiftOp ( ARMNeonShiftOp op ) {
   switch (op) {
      case ARMneon_VSHL: return "vshl";
      case ARMneon_VSAL: return "vshl";
      case ARMneon_VQSHL: return "vqshl";
      case ARMneon_VQSAL: return "vqshl";
      /* ... */
      default: vpanic("showARMNeonShiftOp");
   }
}

const HChar* showARMNeonShiftOpDataType ( ARMNeonShiftOp op ) {
   switch (op) {
      case ARMneon_VSHL:
      case ARMneon_VQSHL:
         return ".u";
      case ARMneon_VSAL:
      case ARMneon_VQSAL:
         return ".s";
      /* ... */
      default: vpanic("showARMNeonShiftOpDataType");
   }
}

const HChar* showARMNeonDualOp ( ARMNeonDualOp op ) {
   switch (op) {
      case ARMneon_TRN: return "vtrn";
      case ARMneon_ZIP: return "vzip";
      case ARMneon_UZP: return "vuzp";
      /* ... */
      default: vpanic("showARMNeonDualOp");
   }
}

const HChar* showARMNeonDualOpDataType ( ARMNeonDualOp op ) {
   switch (op) {
      case ARMneon_TRN:
      case ARMneon_ZIP:
      case ARMneon_UZP:
         return "i";
      /* ... */
      default: vpanic("showARMNeonDualOp");
   }
}

static const HChar* showARMNeonDataSize_wrk ( UInt size )
{
   switch (size) {
      case 0: return "8";
      case 1: return "16";
      case 2: return "32";
      case 3: return "64";
      default: vpanic("showARMNeonDataSize");
   }
}

static const HChar* showARMNeonDataSize ( ARMInstr* i )
{
   switch (i->tag) {
      case ARMin_NBinary:
         if (i->ARMin.NBinary.op == ARMneon_VEXT)
            return "8";
         if (i->ARMin.NBinary.op == ARMneon_VAND ||
             i->ARMin.NBinary.op == ARMneon_VORR ||
             i->ARMin.NBinary.op == ARMneon_VXOR)
            return "";
         return showARMNeonDataSize_wrk(i->ARMin.NBinary.size);
      case ARMin_NUnary:
         if (i->ARMin.NUnary.op == ARMneon_COPY ||
             i->ARMin.NUnary.op == ARMneon_NOT ||
             i->ARMin.NUnary.op == ARMneon_VCVTF32toF16||
             i->ARMin.NUnary.op == ARMneon_VCVTF16toF32||
             i->ARMin.NUnary.op == ARMneon_VCVTFtoFixedS ||
             i->ARMin.NUnary.op == ARMneon_VCVTFtoFixedU ||
             i->ARMin.NUnary.op == ARMneon_VCVTFixedStoF ||
             i->ARMin.NUnary.op == ARMneon_VCVTFixedUtoF ||
             i->ARMin.NUnary.op == ARMneon_VCVTFtoS ||
             i->ARMin.NUnary.op == ARMneon_VCVTFtoU ||
             i->ARMin.NUnary.op == ARMneon_VCVTStoF ||
             i->ARMin.NUnary.op == ARMneon_VCVTUtoF)
            return "";
         if (i->ARMin.NUnary.op == ARMneon_VQSHLNSS ||
             i->ARMin.NUnary.op == ARMneon_VQSHLNUU ||
             i->ARMin.NUnary.op == ARMneon_VQSHLNUS) {
            UInt size;
            size = i->ARMin.NUnary.size;
            if (size & 0x40)
               return "64";
            if (size & 0x20)
               return "32";
            if (size & 0x10)
               return "16";
            if (size & 0x08)
               return "8";
            vpanic("showARMNeonDataSize");
         }
         return showARMNeonDataSize_wrk(i->ARMin.NUnary.size);
      case ARMin_NUnaryS:
         if (i->ARMin.NUnaryS.op == ARMneon_VDUP) {
            int size;
            size = i->ARMin.NUnaryS.size;
            if ((size & 1) == 1)
               return "8";
            if ((size & 3) == 2)
               return "16";
            if ((size & 7) == 4)
               return "32";
            vpanic("showARMNeonDataSize");
         }
         return showARMNeonDataSize_wrk(i->ARMin.NUnaryS.size);
      case ARMin_NShift:
         return showARMNeonDataSize_wrk(i->ARMin.NShift.size);
      case ARMin_NDual:
         return showARMNeonDataSize_wrk(i->ARMin.NDual.size);
      default:
         vpanic("showARMNeonDataSize");
   }
}

ARMInstr* ARMInstr_Alu ( ARMAluOp op,
                         HReg dst, HReg argL, ARMRI84* argR ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag            = ARMin_Alu;
   i->ARMin.Alu.op   = op;
   i->ARMin.Alu.dst  = dst;
   i->ARMin.Alu.argL = argL;
   i->ARMin.Alu.argR = argR;
   return i;
}
ARMInstr* ARMInstr_Shift  ( ARMShiftOp op,
                            HReg dst, HReg argL, ARMRI5* argR ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag              = ARMin_Shift;
   i->ARMin.Shift.op   = op;
   i->ARMin.Shift.dst  = dst;
   i->ARMin.Shift.argL = argL;
   i->ARMin.Shift.argR = argR;
   return i;
}
ARMInstr* ARMInstr_Unary ( ARMUnaryOp op, HReg dst, HReg src ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag             = ARMin_Unary;
   i->ARMin.Unary.op  = op;
   i->ARMin.Unary.dst = dst;
   i->ARMin.Unary.src = src;
   return i;
}
ARMInstr* ARMInstr_CmpOrTst ( Bool isCmp, HReg argL, ARMRI84* argR ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag                  = ARMin_CmpOrTst;
   i->ARMin.CmpOrTst.isCmp = isCmp;
   i->ARMin.CmpOrTst.argL  = argL;
   i->ARMin.CmpOrTst.argR  = argR;
   return i;
}
ARMInstr* ARMInstr_Mov ( HReg dst, ARMRI84* src ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag           = ARMin_Mov;
   i->ARMin.Mov.dst = dst;
   i->ARMin.Mov.src = src;
   return i;
}
ARMInstr* ARMInstr_Imm32  ( HReg dst, UInt imm32 ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag               = ARMin_Imm32;
   i->ARMin.Imm32.dst   = dst;
   i->ARMin.Imm32.imm32 = imm32;
   return i;
}
ARMInstr* ARMInstr_LdSt32 ( ARMCondCode cc,
                            Bool isLoad, HReg rD, ARMAMode1* amode ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag                 = ARMin_LdSt32;
   i->ARMin.LdSt32.cc     = cc;
   i->ARMin.LdSt32.isLoad = isLoad;
   i->ARMin.LdSt32.rD     = rD;
   i->ARMin.LdSt32.amode  = amode;
   vassert(cc != ARMcc_NV);
   return i;
}
ARMInstr* ARMInstr_LdSt16 ( ARMCondCode cc,
                            Bool isLoad, Bool signedLoad,
                            HReg rD, ARMAMode2* amode ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag                     = ARMin_LdSt16;
   i->ARMin.LdSt16.cc         = cc;
   i->ARMin.LdSt16.isLoad     = isLoad;
   i->ARMin.LdSt16.signedLoad = signedLoad;
   i->ARMin.LdSt16.rD         = rD;
   i->ARMin.LdSt16.amode      = amode;
   vassert(cc != ARMcc_NV);
   return i;
}
ARMInstr* ARMInstr_LdSt8U ( ARMCondCode cc,
                            Bool isLoad, HReg rD, ARMAMode1* amode ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag                 = ARMin_LdSt8U;
   i->ARMin.LdSt8U.cc     = cc;
   i->ARMin.LdSt8U.isLoad = isLoad;
   i->ARMin.LdSt8U.rD     = rD;
   i->ARMin.LdSt8U.amode  = amode;
   vassert(cc != ARMcc_NV);
   return i;
}
ARMInstr* ARMInstr_Ld8S ( ARMCondCode cc, HReg rD, ARMAMode2* amode ) {
   ARMInstr* i         = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag              = ARMin_Ld8S;
   i->ARMin.Ld8S.cc    = cc;
   i->ARMin.Ld8S.rD    = rD;
   i->ARMin.Ld8S.amode = amode;
   vassert(cc != ARMcc_NV);
   return i;
}
ARMInstr* ARMInstr_XDirect ( Addr32 dstGA, ARMAMode1* amR15T,
                             ARMCondCode cond, Bool toFastEP ) {
   ARMInstr* i               = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag                    = ARMin_XDirect;
   i->ARMin.XDirect.dstGA    = dstGA;
   i->ARMin.XDirect.amR15T   = amR15T;
   i->ARMin.XDirect.cond     = cond;
   i->ARMin.XDirect.toFastEP = toFastEP;
   return i;
}
ARMInstr* ARMInstr_XIndir ( HReg dstGA, ARMAMode1* amR15T,
                            ARMCondCode cond ) {
   ARMInstr* i            = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag                 = ARMin_XIndir;
   i->ARMin.XIndir.dstGA  = dstGA;
   i->ARMin.XIndir.amR15T = amR15T;
   i->ARMin.XIndir.cond   = cond;
   return i;
}
ARMInstr* ARMInstr_XAssisted ( HReg dstGA, ARMAMode1* amR15T,
                               ARMCondCode cond, IRJumpKind jk ) {
   ARMInstr* i               = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag                    = ARMin_XAssisted;
   i->ARMin.XAssisted.dstGA  = dstGA;
   i->ARMin.XAssisted.amR15T = amR15T;
   i->ARMin.XAssisted.cond   = cond;
   i->ARMin.XAssisted.jk     = jk;
   return i;
}
ARMInstr* ARMInstr_CMov ( ARMCondCode cond, HReg dst, ARMRI84* src ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag             = ARMin_CMov;
   i->ARMin.CMov.cond = cond;
   i->ARMin.CMov.dst  = dst;
   i->ARMin.CMov.src  = src;
   vassert(cond != ARMcc_AL);
   return i;
}
ARMInstr* ARMInstr_Call ( ARMCondCode cond, HWord target, Int nArgRegs,
                          RetLoc rloc ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag                 = ARMin_Call;
   i->ARMin.Call.cond     = cond;
   i->ARMin.Call.target   = target;
   i->ARMin.Call.nArgRegs = nArgRegs;
   i->ARMin.Call.rloc     = rloc;
   vassert(is_sane_RetLoc(rloc));
   return i;
}
ARMInstr* ARMInstr_Mul ( ARMMulOp op ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag          = ARMin_Mul;
   i->ARMin.Mul.op = op;
   return i;
}
ARMInstr* ARMInstr_LdrEX ( Int szB ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag             = ARMin_LdrEX;
   i->ARMin.LdrEX.szB = szB;
   vassert(szB == 8 || szB == 4 || szB == 2 || szB == 1);
   return i;
}
ARMInstr* ARMInstr_StrEX ( Int szB ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag             = ARMin_StrEX;
   i->ARMin.StrEX.szB = szB;
   vassert(szB == 8 || szB == 4 || szB == 2 || szB == 1);
   return i;
}
ARMInstr* ARMInstr_VLdStD ( Bool isLoad, HReg dD, ARMAModeV* am ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag                 = ARMin_VLdStD;
   i->ARMin.VLdStD.isLoad = isLoad;
   i->ARMin.VLdStD.dD     = dD;
   i->ARMin.VLdStD.amode  = am;
   return i;
}
ARMInstr* ARMInstr_VLdStS ( Bool isLoad, HReg fD, ARMAModeV* am ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag                 = ARMin_VLdStS;
   i->ARMin.VLdStS.isLoad = isLoad;
   i->ARMin.VLdStS.fD     = fD;
   i->ARMin.VLdStS.amode  = am;
   return i;
}
ARMInstr* ARMInstr_VAluD ( ARMVfpOp op, HReg dst, HReg argL, HReg argR ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag              = ARMin_VAluD;
   i->ARMin.VAluD.op   = op;
   i->ARMin.VAluD.dst  = dst;
   i->ARMin.VAluD.argL = argL;
   i->ARMin.VAluD.argR = argR;
   return i;
}
ARMInstr* ARMInstr_VAluS ( ARMVfpOp op, HReg dst, HReg argL, HReg argR ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag              = ARMin_VAluS;
   i->ARMin.VAluS.op   = op;
   i->ARMin.VAluS.dst  = dst;
   i->ARMin.VAluS.argL = argL;
   i->ARMin.VAluS.argR = argR;
   return i;
}
ARMInstr* ARMInstr_VUnaryD ( ARMVfpUnaryOp op, HReg dst, HReg src ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag               = ARMin_VUnaryD;
   i->ARMin.VUnaryD.op  = op;
   i->ARMin.VUnaryD.dst = dst;
   i->ARMin.VUnaryD.src = src;
   return i;
}
ARMInstr* ARMInstr_VUnaryS ( ARMVfpUnaryOp op, HReg dst, HReg src ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag               = ARMin_VUnaryS;
   i->ARMin.VUnaryS.op  = op;
   i->ARMin.VUnaryS.dst = dst;
   i->ARMin.VUnaryS.src = src;
   return i;
}
ARMInstr* ARMInstr_VCmpD ( HReg argL, HReg argR ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag              = ARMin_VCmpD;
   i->ARMin.VCmpD.argL = argL;
   i->ARMin.VCmpD.argR = argR;
   return i;
}
ARMInstr* ARMInstr_VCMovD ( ARMCondCode cond, HReg dst, HReg src ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag               = ARMin_VCMovD;
   i->ARMin.VCMovD.cond = cond;
   i->ARMin.VCMovD.dst  = dst;
   i->ARMin.VCMovD.src  = src;
   vassert(cond != ARMcc_AL);
   return i;
}
ARMInstr* ARMInstr_VCMovS ( ARMCondCode cond, HReg dst, HReg src ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag               = ARMin_VCMovS;
   i->ARMin.VCMovS.cond = cond;
   i->ARMin.VCMovS.dst  = dst;
   i->ARMin.VCMovS.src  = src;
   vassert(cond != ARMcc_AL);
   return i;
}
ARMInstr* ARMInstr_VCvtSD ( Bool sToD, HReg dst, HReg src ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag               = ARMin_VCvtSD;
   i->ARMin.VCvtSD.sToD = sToD;
   i->ARMin.VCvtSD.dst  = dst;
   i->ARMin.VCvtSD.src  = src;
   return i;
}
ARMInstr* ARMInstr_VXferD ( Bool toD, HReg dD, HReg rHi, HReg rLo ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag              = ARMin_VXferD;
   i->ARMin.VXferD.toD = toD;
   i->ARMin.VXferD.dD  = dD;
   i->ARMin.VXferD.rHi = rHi;
   i->ARMin.VXferD.rLo = rLo;
   return i;
}
ARMInstr* ARMInstr_VXferS ( Bool toS, HReg fD, HReg rLo ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag              = ARMin_VXferS;
   i->ARMin.VXferS.toS = toS;
   i->ARMin.VXferS.fD  = fD;
   i->ARMin.VXferS.rLo = rLo;
   return i;
}
ARMInstr* ARMInstr_VCvtID ( Bool iToD, Bool syned,
                            HReg dst, HReg src ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag                = ARMin_VCvtID;
   i->ARMin.VCvtID.iToD  = iToD;
   i->ARMin.VCvtID.syned = syned;
   i->ARMin.VCvtID.dst   = dst;
   i->ARMin.VCvtID.src   = src;
   return i;
}
ARMInstr* ARMInstr_FPSCR ( Bool toFPSCR, HReg iReg ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag                 = ARMin_FPSCR;
   i->ARMin.FPSCR.toFPSCR = toFPSCR;
   i->ARMin.FPSCR.iReg    = iReg;
   return i;
}
ARMInstr* ARMInstr_MFence ( void ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag      = ARMin_MFence;
   return i;
}
ARMInstr* ARMInstr_CLREX( void ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag      = ARMin_CLREX;
   return i;
}

ARMInstr* ARMInstr_NLdStQ ( Bool isLoad, HReg dQ, ARMAModeN *amode ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag                  = ARMin_NLdStQ;
   i->ARMin.NLdStQ.isLoad  = isLoad;
   i->ARMin.NLdStQ.dQ      = dQ;
   i->ARMin.NLdStQ.amode   = amode;
   return i;
}

ARMInstr* ARMInstr_NLdStD ( Bool isLoad, HReg dD, ARMAModeN *amode ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag                  = ARMin_NLdStD;
   i->ARMin.NLdStD.isLoad  = isLoad;
   i->ARMin.NLdStD.dD      = dD;
   i->ARMin.NLdStD.amode   = amode;
   return i;
}

ARMInstr* ARMInstr_NUnary ( ARMNeonUnOp op, HReg dQ, HReg nQ,
                            UInt size, Bool Q ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag                = ARMin_NUnary;
   i->ARMin.NUnary.op   = op;
   i->ARMin.NUnary.src  = nQ;
   i->ARMin.NUnary.dst  = dQ;
   i->ARMin.NUnary.size = size;
   i->ARMin.NUnary.Q    = Q;
   return i;
}

ARMInstr* ARMInstr_NUnaryS ( ARMNeonUnOpS op, ARMNRS* dst, ARMNRS* src,
                             UInt size, Bool Q ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag                = ARMin_NUnaryS;
   i->ARMin.NUnaryS.op   = op;
   i->ARMin.NUnaryS.src  = src;
   i->ARMin.NUnaryS.dst  = dst;
   i->ARMin.NUnaryS.size = size;
   i->ARMin.NUnaryS.Q    = Q;
   return i;
}

ARMInstr* ARMInstr_NDual ( ARMNeonDualOp op, HReg nQ, HReg mQ,
                           UInt size, Bool Q ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag                = ARMin_NDual;
   i->ARMin.NDual.op   = op;
   i->ARMin.NDual.arg1 = nQ;
   i->ARMin.NDual.arg2 = mQ;
   i->ARMin.NDual.size = size;
   i->ARMin.NDual.Q    = Q;
   return i;
}

ARMInstr* ARMInstr_NBinary ( ARMNeonBinOp op,
                             HReg dst, HReg argL, HReg argR,
                             UInt size, Bool Q ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag                = ARMin_NBinary;
   i->ARMin.NBinary.op   = op;
   i->ARMin.NBinary.argL = argL;
   i->ARMin.NBinary.argR = argR;
   i->ARMin.NBinary.dst  = dst;
   i->ARMin.NBinary.size = size;
   i->ARMin.NBinary.Q    = Q;
   return i;
}

ARMInstr* ARMInstr_NeonImm (HReg dst, ARMNImm* imm ) {
   ARMInstr *i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag         = ARMin_NeonImm;
   i->ARMin.NeonImm.dst = dst;
   i->ARMin.NeonImm.imm = imm;
   return i;
}

ARMInstr* ARMInstr_NCMovQ ( ARMCondCode cond, HReg dst, HReg src ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag               = ARMin_NCMovQ;
   i->ARMin.NCMovQ.cond = cond;
   i->ARMin.NCMovQ.dst  = dst;
   i->ARMin.NCMovQ.src  = src;
   vassert(cond != ARMcc_AL);
   return i;
}

ARMInstr* ARMInstr_NShift ( ARMNeonShiftOp op,
                            HReg dst, HReg argL, HReg argR,
                            UInt size, Bool Q ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag                = ARMin_NShift;
   i->ARMin.NShift.op   = op;
   i->ARMin.NShift.argL = argL;
   i->ARMin.NShift.argR = argR;
   i->ARMin.NShift.dst  = dst;
   i->ARMin.NShift.size = size;
   i->ARMin.NShift.Q    = Q;
   return i;
}

ARMInstr* ARMInstr_NShl64 ( HReg dst, HReg src, UInt amt )
{
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag              = ARMin_NShl64;
   i->ARMin.NShl64.dst = dst;
   i->ARMin.NShl64.src = src;
   i->ARMin.NShl64.amt = amt;
   vassert(amt >= 1 && amt <= 63);
   return i;
}

/* Helper copy-pasted from isel.c */
static Bool fitsIn8x4 ( UInt* u8, UInt* u4, UInt u )
{
   UInt i;
   for (i = 0; i < 16; i++) {
      if (0 == (u & 0xFFFFFF00)) {
         *u8 = u;
         *u4 = i;
         return True;
      }
      u = ROR32(u, 30);
   }
   vassert(i == 16);
   return False;
}

ARMInstr* ARMInstr_Add32 ( HReg rD, HReg rN, UInt imm32 ) {
   UInt u8, u4;
   ARMInstr *i = LibVEX_Alloc(sizeof(ARMInstr));
   /* Try to generate single ADD if possible */
   if (fitsIn8x4(&u8, &u4, imm32)) {
      i->tag            = ARMin_Alu;
      i->ARMin.Alu.op   = ARMalu_ADD;
      i->ARMin.Alu.dst  = rD;
      i->ARMin.Alu.argL = rN;
      i->ARMin.Alu.argR = ARMRI84_I84(u8, u4);
   } else {
      i->tag               = ARMin_Add32;
      i->ARMin.Add32.rD    = rD;
      i->ARMin.Add32.rN    = rN;
      i->ARMin.Add32.imm32 = imm32;
   }
   return i;
}

ARMInstr* ARMInstr_EvCheck ( ARMAMode1* amCounter,
                             ARMAMode1* amFailAddr ) {
   ARMInstr* i                 = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag                      = ARMin_EvCheck;
   i->ARMin.EvCheck.amCounter  = amCounter;
   i->ARMin.EvCheck.amFailAddr = amFailAddr;
   return i;
}

ARMInstr* ARMInstr_ProfInc ( void ) {
   ARMInstr* i = LibVEX_Alloc(sizeof(ARMInstr));
   i->tag      = ARMin_ProfInc;
   return i;
}

/* ... */

void ppARMInstr ( ARMInstr* i ) {
   switch (i->tag) {
      case ARMin_Alu:
         vex_printf("%-4s  ", showARMAluOp(i->ARMin.Alu.op));
         ppHRegARM(i->ARMin.Alu.dst);
         vex_printf(", ");
         ppHRegARM(i->ARMin.Alu.argL);
         vex_printf(", ");
         ppARMRI84(i->ARMin.Alu.argR);
         return;
      case ARMin_Shift:
         vex_printf("%s   ", showARMShiftOp(i->ARMin.Shift.op));
         ppHRegARM(i->ARMin.Shift.dst);
         vex_printf(", ");
         ppHRegARM(i->ARMin.Shift.argL);
         vex_printf(", ");
         ppARMRI5(i->ARMin.Shift.argR);
         return;
      case ARMin_Unary:
         vex_printf("%s   ", showARMUnaryOp(i->ARMin.Unary.op));
         ppHRegARM(i->ARMin.Unary.dst);
         vex_printf(", ");
         ppHRegARM(i->ARMin.Unary.src);
         return;
      case ARMin_CmpOrTst:
         vex_printf("%s   ", i->ARMin.CmpOrTst.isCmp ? "cmp" : "tst");
         ppHRegARM(i->ARMin.CmpOrTst.argL);
         vex_printf(", ");
         ppARMRI84(i->ARMin.CmpOrTst.argR);
         return;
      case ARMin_Mov:
         vex_printf("mov   ");
         ppHRegARM(i->ARMin.Mov.dst);
         vex_printf(", ");
         ppARMRI84(i->ARMin.Mov.src);
         return;
      case ARMin_Imm32:
         vex_printf("imm   ");
         ppHRegARM(i->ARMin.Imm32.dst);
         vex_printf(", 0x%x", i->ARMin.Imm32.imm32);
         return;
      case ARMin_LdSt32:
         if (i->ARMin.LdSt32.isLoad) {
            vex_printf("ldr%s ", i->ARMin.LdSt32.cc == ARMcc_AL ? "  "
                                    : showARMCondCode(i->ARMin.LdSt32.cc));
            ppHRegARM(i->ARMin.LdSt32.rD);
            vex_printf(", ");
            ppARMAMode1(i->ARMin.LdSt32.amode);
         } else {
            vex_printf("str%s ", i->ARMin.LdSt32.cc == ARMcc_AL ? "  "
                                    : showARMCondCode(i->ARMin.LdSt32.cc));
            ppARMAMode1(i->ARMin.LdSt32.amode);
            vex_printf(", ");
            ppHRegARM(i->ARMin.LdSt32.rD);
         }
         return;
      case ARMin_LdSt16:
         if (i->ARMin.LdSt16.isLoad) {
            vex_printf("%s%s%s",
                       i->ARMin.LdSt16.signedLoad ? "ldrsh" : "ldrh",
                       i->ARMin.LdSt16.cc == ARMcc_AL ? "  "
                          : showARMCondCode(i->ARMin.LdSt16.cc),
                       i->ARMin.LdSt16.signedLoad ? " " : "  ");
            ppHRegARM(i->ARMin.LdSt16.rD);
            vex_printf(", ");
            ppARMAMode2(i->ARMin.LdSt16.amode);
         } else {
            vex_printf("strh%s  ",
                       i->ARMin.LdSt16.cc == ARMcc_AL ? "  "
                          : showARMCondCode(i->ARMin.LdSt16.cc));
            ppARMAMode2(i->ARMin.LdSt16.amode);
            vex_printf(", ");
            ppHRegARM(i->ARMin.LdSt16.rD);
         }
         return;
      case ARMin_LdSt8U:
         if (i->ARMin.LdSt8U.isLoad) {
            vex_printf("ldrb%s  ", i->ARMin.LdSt8U.cc == ARMcc_AL ? "  "
                                      : showARMCondCode(i->ARMin.LdSt8U.cc));
            ppHRegARM(i->ARMin.LdSt8U.rD);
            vex_printf(", ");
            ppARMAMode1(i->ARMin.LdSt8U.amode);
         } else {
            vex_printf("strb%s  ", i->ARMin.LdSt8U.cc == ARMcc_AL ? "  "
                                      : showARMCondCode(i->ARMin.LdSt8U.cc));
            ppARMAMode1(i->ARMin.LdSt8U.amode);
            vex_printf(", ");
            ppHRegARM(i->ARMin.LdSt8U.rD);
         }
         return;
      case ARMin_Ld8S:
         vex_printf("ldrsb%s ", i->ARMin.Ld8S.cc == ARMcc_AL ? "  "
                                   : showARMCondCode(i->ARMin.Ld8S.cc));
         ppARMAMode2(i->ARMin.Ld8S.amode);
         vex_printf(", ");
         ppHRegARM(i->ARMin.Ld8S.rD);
         return;
      case ARMin_XDirect:
         vex_printf("(xDirect) ");
         vex_printf("if (%%cpsr.%s) { ",
                    showARMCondCode(i->ARMin.XDirect.cond));
         vex_printf("movw r12,0x%x; ",
                    (UInt)(i->ARMin.XDirect.dstGA & 0xFFFF));
         vex_printf("movt r12,0x%x; ",
                    (UInt)((i->ARMin.XDirect.dstGA >> 16) & 0xFFFF));
         vex_printf("str r12,");
         ppARMAMode1(i->ARMin.XDirect.amR15T);
         vex_printf("; movw r12,LO16($disp_cp_chain_me_to_%sEP); ",
                    i->ARMin.XDirect.toFastEP ? "fast" : "slow");
         vex_printf("movt r12,HI16($disp_cp_chain_me_to_%sEP); ",
                    i->ARMin.XDirect.toFastEP ? "fast" : "slow");
         vex_printf("blx r12 }");
         return;
      case ARMin_XIndir:
         vex_printf("(xIndir) ");
         vex_printf("if (%%cpsr.%s) { ",
                    showARMCondCode(i->ARMin.XIndir.cond));
         vex_printf("str ");
         ppHRegARM(i->ARMin.XIndir.dstGA);
         vex_printf(",");
         ppARMAMode1(i->ARMin.XIndir.amR15T);
         vex_printf("; movw r12,LO16($disp_cp_xindir); ");
         vex_printf("movt r12,HI16($disp_cp_xindir); ");
         vex_printf("blx r12 }");
         return;
      case ARMin_XAssisted:
         vex_printf("(xAssisted) ");
         vex_printf("if (%%cpsr.%s) { ",
                    showARMCondCode(i->ARMin.XAssisted.cond));
         vex_printf("str ");
         ppHRegARM(i->ARMin.XAssisted.dstGA);
         vex_printf(",");
         ppARMAMode1(i->ARMin.XAssisted.amR15T);
         vex_printf("movw r8,$IRJumpKind_to_TRCVAL(%d); ",
                    (Int)i->ARMin.XAssisted.jk);
         vex_printf("movw r12,LO16($disp_cp_xassisted); ");
         vex_printf("movt r12,HI16($disp_cp_xassisted); ");
         vex_printf("blx r12 }");
         return;
      case ARMin_CMov:
         vex_printf("mov%s ", showARMCondCode(i->ARMin.CMov.cond));
         ppHRegARM(i->ARMin.CMov.dst);
         vex_printf(", ");
         ppARMRI84(i->ARMin.CMov.src);
         return;
      case ARMin_Call:
         vex_printf("call%s  ",
                    i->ARMin.Call.cond==ARMcc_AL
                       ? "" : showARMCondCode(i->ARMin.Call.cond));
         vex_printf("0x%lx [nArgRegs=%d, ",
                    i->ARMin.Call.target, i->ARMin.Call.nArgRegs);
         ppRetLoc(i->ARMin.Call.rloc);
         vex_printf("]");
         return;
      case ARMin_Mul:
         vex_printf("%-5s ", showARMMulOp(i->ARMin.Mul.op));
         if (i->ARMin.Mul.op == ARMmul_PLAIN) {
            vex_printf("r0, r2, r3");
         } else {
            vex_printf("r1:r0, r2, r3");
         }
         return;
      case ARMin_LdrEX: {
         const HChar* sz = "";
         switch (i->ARMin.LdrEX.szB) {
            case 1: sz = "b"; break; case 2: sz = "h"; break;
            case 8: sz = "d"; break; case 4: break;
            default: vassert(0);
         }
         vex_printf("ldrex%s %sr2, [r4]",
                    sz, i->ARMin.LdrEX.szB == 8 ? "r3:" : "");
         return;
      }
      case ARMin_StrEX: {
         const HChar* sz = "";
         switch (i->ARMin.StrEX.szB) {
            case 1: sz = "b"; break; case 2: sz = "h"; break;
            case 8: sz = "d"; break; case 4: break;
            default: vassert(0);
         }
         vex_printf("strex%s r0, %sr2, [r4]",
                    sz, i->ARMin.StrEX.szB == 8 ? "r3:" : "");
         return;
      }
      case ARMin_VLdStD:
         if (i->ARMin.VLdStD.isLoad) {
            vex_printf("fldd  ");
            ppHRegARM(i->ARMin.VLdStD.dD);
            vex_printf(", ");
            ppARMAModeV(i->ARMin.VLdStD.amode);
         } else {
            vex_printf("fstd  ");
            ppARMAModeV(i->ARMin.VLdStD.amode);
            vex_printf(", ");
            ppHRegARM(i->ARMin.VLdStD.dD);
         }
         return;
      case ARMin_VLdStS:
         if (i->ARMin.VLdStS.isLoad) {
            vex_printf("flds  ");
            ppHRegARM(i->ARMin.VLdStS.fD);
            vex_printf(", ");
            ppARMAModeV(i->ARMin.VLdStS.amode);
         } else {
            vex_printf("fsts  ");
            ppARMAModeV(i->ARMin.VLdStS.amode);
            vex_printf(", ");
            ppHRegARM(i->ARMin.VLdStS.fD);
         }
         return;
      case ARMin_VAluD:
         vex_printf("f%-3sd ", showARMVfpOp(i->ARMin.VAluD.op));
         ppHRegARM(i->ARMin.VAluD.dst);
         vex_printf(", ");
         ppHRegARM(i->ARMin.VAluD.argL);
         vex_printf(", ");
         ppHRegARM(i->ARMin.VAluD.argR);
         return;
      case ARMin_VAluS:
         vex_printf("f%-3ss ", showARMVfpOp(i->ARMin.VAluS.op));
         ppHRegARM(i->ARMin.VAluS.dst);
         vex_printf(", ");
         ppHRegARM(i->ARMin.VAluS.argL);
         vex_printf(", ");
         ppHRegARM(i->ARMin.VAluS.argR);
         return;
      case ARMin_VUnaryD:
         vex_printf("f%-3sd ", showARMVfpUnaryOp(i->ARMin.VUnaryD.op));
         ppHRegARM(i->ARMin.VUnaryD.dst);
         vex_printf(", ");
         ppHRegARM(i->ARMin.VUnaryD.src);
         return;
      case ARMin_VUnaryS:
         vex_printf("f%-3ss ", showARMVfpUnaryOp(i->ARMin.VUnaryS.op));
         ppHRegARM(i->ARMin.VUnaryS.dst);
         vex_printf(", ");
         ppHRegARM(i->ARMin.VUnaryS.src);
         return;
      case ARMin_VCmpD:
         vex_printf("fcmpd ");
         ppHRegARM(i->ARMin.VCmpD.argL);
         vex_printf(", ");
         ppHRegARM(i->ARMin.VCmpD.argR);
         vex_printf(" ; fmstat");
         return;
      case ARMin_VCMovD:
         vex_printf("fcpyd%s ", showARMCondCode(i->ARMin.VCMovD.cond));
         ppHRegARM(i->ARMin.VCMovD.dst);
         vex_printf(", ");
         ppHRegARM(i->ARMin.VCMovD.src);
         return;
      case ARMin_VCMovS:
         vex_printf("fcpys%s ", showARMCondCode(i->ARMin.VCMovS.cond));
         ppHRegARM(i->ARMin.VCMovS.dst);
         vex_printf(", ");
         ppHRegARM(i->ARMin.VCMovS.src);
         return;
      case ARMin_VCvtSD:
         vex_printf("fcvt%s ", i->ARMin.VCvtSD.sToD ? "ds" : "sd");
         ppHRegARM(i->ARMin.VCvtSD.dst);
         vex_printf(", ");
         ppHRegARM(i->ARMin.VCvtSD.src);
         return;
      case ARMin_VXferD:
         vex_printf("vmov  ");
         if (i->ARMin.VXferD.toD) {
            ppHRegARM(i->ARMin.VXferD.dD);
            vex_printf(", ");
            ppHRegARM(i->ARMin.VXferD.rLo);
            vex_printf(", ");
            ppHRegARM(i->ARMin.VXferD.rHi);
         } else {
            ppHRegARM(i->ARMin.VXferD.rLo);
            vex_printf(", ");
            ppHRegARM(i->ARMin.VXferD.rHi);
            vex_printf(", ");
            ppHRegARM(i->ARMin.VXferD.dD);
         }
         return;
      case ARMin_VXferS:
         vex_printf("vmov  ");
         if (i->ARMin.VXferS.toS) {
            ppHRegARM(i->ARMin.VXferS.fD);
            vex_printf(", ");
            ppHRegARM(i->ARMin.VXferS.rLo);
         } else {
            ppHRegARM(i->ARMin.VXferS.rLo);
            vex_printf(", ");
            ppHRegARM(i->ARMin.VXferS.fD);
         }
         return;
      case ARMin_VCvtID: {
         const HChar* nm = "?";
         if (i->ARMin.VCvtID.iToD) {
            nm = i->ARMin.VCvtID.syned ? "fsitod" : "fuitod";
         } else {
            nm = i->ARMin.VCvtID.syned ? "ftosid" : "ftouid";
         }
         vex_printf("%s ", nm);
         ppHRegARM(i->ARMin.VCvtID.dst);
         vex_printf(", ");
         ppHRegARM(i->ARMin.VCvtID.src);
         return;
      }
      case ARMin_FPSCR:
         if (i->ARMin.FPSCR.toFPSCR) {
            vex_printf("fmxr  fpscr, ");
            ppHRegARM(i->ARMin.FPSCR.iReg);
         } else {
            vex_printf("fmrx  ");
            ppHRegARM(i->ARMin.FPSCR.iReg);
            vex_printf(", fpscr");
         }
         return;
      case ARMin_MFence:
         vex_printf("(mfence) dsb sy; dmb sy; isb");
         return;
      case ARMin_CLREX:
         vex_printf("clrex");
         return;
      case ARMin_NLdStQ:
         if (i->ARMin.NLdStQ.isLoad)
            vex_printf("vld1.32 {");
         else
            vex_printf("vst1.32 {");
         ppHRegARM(i->ARMin.NLdStQ.dQ);
         vex_printf("} ");
         ppARMAModeN(i->ARMin.NLdStQ.amode);
         return;
      case ARMin_NLdStD:
         if (i->ARMin.NLdStD.isLoad)
            vex_printf("vld1.32 {");
         else
            vex_printf("vst1.32 {");
         ppHRegARM(i->ARMin.NLdStD.dD);
         vex_printf("} ");
         ppARMAModeN(i->ARMin.NLdStD.amode);
         return;
      case ARMin_NUnary:
         vex_printf("%s%s%s  ",
                    showARMNeonUnOp(i->ARMin.NUnary.op),
                    showARMNeonUnOpDataType(i->ARMin.NUnary.op),
                    showARMNeonDataSize(i));
         ppHRegARM(i->ARMin.NUnary.dst);
         vex_printf(", ");
         ppHRegARM(i->ARMin.NUnary.src);
         if (i->ARMin.NUnary.op == ARMneon_EQZ)
            vex_printf(", #0");
         if (i->ARMin.NUnary.op == ARMneon_VCVTFtoFixedS ||
             i->ARMin.NUnary.op == ARMneon_VCVTFtoFixedU ||
             i->ARMin.NUnary.op == ARMneon_VCVTFixedStoF ||
             i->ARMin.NUnary.op == ARMneon_VCVTFixedUtoF) {
            vex_printf(", #%d", i->ARMin.NUnary.size);
         }
         if (i->ARMin.NUnary.op == ARMneon_VQSHLNSS ||
             i->ARMin.NUnary.op == ARMneon_VQSHLNUU ||
             i->ARMin.NUnary.op == ARMneon_VQSHLNUS) {
            UInt size;
            size = i->ARMin.NUnary.size;
            if (size & 0x40) {
               vex_printf(", #%d", size - 64);
            } else if (size & 0x20) {
               vex_printf(", #%d", size - 32);
            } else if (size & 0x10) {
               vex_printf(", #%d", size - 16);
            } else if (size & 0x08) {
               vex_printf(", #%d", size - 8);
            }
         }
         return;
      case ARMin_NUnaryS:
         vex_printf("%s%s%s  ",
                    showARMNeonUnOpS(i->ARMin.NUnaryS.op),
                    showARMNeonUnOpSDataType(i->ARMin.NUnaryS.op),
                    showARMNeonDataSize(i));
         ppARMNRS(i->ARMin.NUnaryS.dst);
         vex_printf(", ");
         ppARMNRS(i->ARMin.NUnaryS.src);
         return;
      case ARMin_NShift:
         vex_printf("%s%s%s  ",
                    showARMNeonShiftOp(i->ARMin.NShift.op),
                    showARMNeonShiftOpDataType(i->ARMin.NShift.op),
                    showARMNeonDataSize(i));
         ppHRegARM(i->ARMin.NShift.dst);
         vex_printf(", ");
         ppHRegARM(i->ARMin.NShift.argL);
         vex_printf(", ");
         ppHRegARM(i->ARMin.NShift.argR);
         return;
      case ARMin_NShl64:
         vex_printf("vshl.i64 ");
         ppHRegARM(i->ARMin.NShl64.dst);
         vex_printf(", ");
         ppHRegARM(i->ARMin.NShl64.src);
         vex_printf(", #%u", i->ARMin.NShl64.amt);
         return;
      case ARMin_NDual:
         vex_printf("%s%s%s  ",
                    showARMNeonDualOp(i->ARMin.NDual.op),
                    showARMNeonDualOpDataType(i->ARMin.NDual.op),
                    showARMNeonDataSize(i));
         ppHRegARM(i->ARMin.NDual.arg1);
         vex_printf(", ");
         ppHRegARM(i->ARMin.NDual.arg2);
         return;
      case ARMin_NBinary:
         vex_printf("%s%s%s",
                    showARMNeonBinOp(i->ARMin.NBinary.op),
                    showARMNeonBinOpDataType(i->ARMin.NBinary.op),
                    showARMNeonDataSize(i));
         vex_printf("  ");
         ppHRegARM(i->ARMin.NBinary.dst);
         vex_printf(", ");
         ppHRegARM(i->ARMin.NBinary.argL);
         vex_printf(", ");
         ppHRegARM(i->ARMin.NBinary.argR);
         return;
      case ARMin_NeonImm:
         vex_printf("vmov  ");
         ppHRegARM(i->ARMin.NeonImm.dst);
         vex_printf(", ");
         ppARMNImm(i->ARMin.NeonImm.imm);
         return;
      case ARMin_NCMovQ:
         vex_printf("vmov%s ", showARMCondCode(i->ARMin.NCMovQ.cond));
         ppHRegARM(i->ARMin.NCMovQ.dst);
         vex_printf(", ");
         ppHRegARM(i->ARMin.NCMovQ.src);
         return;
      case ARMin_Add32:
         vex_printf("add32 ");
         ppHRegARM(i->ARMin.Add32.rD);
         vex_printf(", ");
         ppHRegARM(i->ARMin.Add32.rN);
         vex_printf(", ");
         vex_printf("%d", i->ARMin.Add32.imm32);
         return;
      case ARMin_EvCheck:
         vex_printf("(evCheck) ldr r12,");
         ppARMAMode1(i->ARMin.EvCheck.amCounter);
         vex_printf("; subs r12,r12,$1; str r12,");
         ppARMAMode1(i->ARMin.EvCheck.amCounter);
         vex_printf("; bpl nofail; ldr r12,");
         ppARMAMode1(i->ARMin.EvCheck.amFailAddr);
         vex_printf("; bx r12; nofail:");
         return;
      case ARMin_ProfInc:
         vex_printf("(profInc) movw r12,LO16($NotKnownYet); "
                    "movw r12,HI16($NotKnownYet); "
                    "ldr r11,[r12]; "
                    "adds r11,r11,$1; "
                    "str r11,[r12]; "
                    "ldr r11,[r12+4]; "
                    "adc r11,r11,$0; "
                    "str r11,[r12+4]");
         return;
      default:
         vex_printf("ppARMInstr: unhandled case (tag %d)", (Int)i->tag);
         vpanic("ppARMInstr(1)");
         return;
   }
}


/* --------- Helpers for register allocation. --------- */

void getRegUsage_ARMInstr ( HRegUsage* u, ARMInstr* i, Bool mode64 )
{
   vassert(mode64 == False);
   initHRegUsage(u);
   switch (i->tag) {
      case ARMin_Alu:
         addHRegUse(u, HRmWrite, i->ARMin.Alu.dst);
         addHRegUse(u, HRmRead, i->ARMin.Alu.argL);
         addRegUsage_ARMRI84(u, i->ARMin.Alu.argR);
         return;
      case ARMin_Shift:
         addHRegUse(u, HRmWrite, i->ARMin.Shift.dst);
         addHRegUse(u, HRmRead, i->ARMin.Shift.argL);
         addRegUsage_ARMRI5(u, i->ARMin.Shift.argR);
         return;
      case ARMin_Unary:
         addHRegUse(u, HRmWrite, i->ARMin.Unary.dst);
         addHRegUse(u, HRmRead, i->ARMin.Unary.src);
         return;
      case ARMin_CmpOrTst:
         addHRegUse(u, HRmRead, i->ARMin.CmpOrTst.argL);
         addRegUsage_ARMRI84(u, i->ARMin.CmpOrTst.argR);
         return;
      case ARMin_Mov:
         addHRegUse(u, HRmWrite, i->ARMin.Mov.dst);
         addRegUsage_ARMRI84(u, i->ARMin.Mov.src);
         return;
      case ARMin_Imm32:
         addHRegUse(u, HRmWrite, i->ARMin.Imm32.dst);
         return;
      case ARMin_LdSt32:
         addRegUsage_ARMAMode1(u, i->ARMin.LdSt32.amode);
         if (i->ARMin.LdSt32.isLoad) {
            addHRegUse(u, HRmWrite, i->ARMin.LdSt32.rD);
            if (i->ARMin.LdSt32.cc != ARMcc_AL)
               addHRegUse(u, HRmRead, i->ARMin.LdSt32.rD);
         } else {
            addHRegUse(u, HRmRead, i->ARMin.LdSt32.rD);
         }
         return;
      case ARMin_LdSt16:
         addRegUsage_ARMAMode2(u, i->ARMin.LdSt16.amode);
         if (i->ARMin.LdSt16.isLoad) {
            addHRegUse(u, HRmWrite, i->ARMin.LdSt16.rD);
            if (i->ARMin.LdSt16.cc != ARMcc_AL)
               addHRegUse(u, HRmRead, i->ARMin.LdSt16.rD);
         } else {
            addHRegUse(u, HRmRead, i->ARMin.LdSt16.rD);
         }
         return;
      case ARMin_LdSt8U:
         addRegUsage_ARMAMode1(u, i->ARMin.LdSt8U.amode);
         if (i->ARMin.LdSt8U.isLoad) {
            addHRegUse(u, HRmWrite, i->ARMin.LdSt8U.rD);
            if (i->ARMin.LdSt8U.cc != ARMcc_AL)
               addHRegUse(u, HRmRead, i->ARMin.LdSt8U.rD);
         } else {
            addHRegUse(u, HRmRead, i->ARMin.LdSt8U.rD);
         }
         return;
      case ARMin_Ld8S:
         addRegUsage_ARMAMode2(u, i->ARMin.Ld8S.amode);
         addHRegUse(u, HRmWrite, i->ARMin.Ld8S.rD);
         if (i->ARMin.Ld8S.cc != ARMcc_AL)
            addHRegUse(u, HRmRead, i->ARMin.Ld8S.rD);
         return;
      /* XDirect/XIndir/XAssisted are also a bit subtle.  They
         conditionally exit the block.  Hence we only need to list (1)
         the registers that they read, and (2) the registers that they
         write in the case where the block is not exited.  (2) is
         empty, hence only (1) is relevant here. */
      case ARMin_XDirect:
         addRegUsage_ARMAMode1(u, i->ARMin.XDirect.amR15T);
         return;
      case ARMin_XIndir:
         addHRegUse(u, HRmRead, i->ARMin.XIndir.dstGA);
         addRegUsage_ARMAMode1(u, i->ARMin.XIndir.amR15T);
         return;
      case ARMin_XAssisted:
         addHRegUse(u, HRmRead, i->ARMin.XAssisted.dstGA);
         addRegUsage_ARMAMode1(u, i->ARMin.XAssisted.amR15T);
         return;
      case ARMin_CMov:
         addHRegUse(u, HRmWrite, i->ARMin.CMov.dst);
         addHRegUse(u, HRmRead,  i->ARMin.CMov.dst);
         addRegUsage_ARMRI84(u, i->ARMin.CMov.src);
         return;
      case ARMin_Call:
         /* logic and comments copied/modified from x86 back end */
         /* This is a bit subtle. */
         /* First off, claim it trashes all the caller-saved regs
            which fall within the register allocator's jurisdiction.
            These I believe to be r0,1,2,3.  If it turns out that r9
            is also caller-saved, then we'll have to add that here
            too. */
         addHRegUse(u, HRmWrite, hregARM_R0());
         addHRegUse(u, HRmWrite, hregARM_R1());
         addHRegUse(u, HRmWrite, hregARM_R2());
         addHRegUse(u, HRmWrite, hregARM_R3());
         /* Now we have to state any parameter-carrying registers
            which might be read.  This depends on nArgRegs. */
         switch (i->ARMin.Call.nArgRegs) {
            case 4: addHRegUse(u, HRmRead, hregARM_R3()); /*fallthru*/
            case 3: addHRegUse(u, HRmRead, hregARM_R2()); /*fallthru*/
            case 2: addHRegUse(u, HRmRead, hregARM_R1()); /*fallthru*/
            case 1: addHRegUse(u, HRmRead, hregARM_R0()); break;
            case 0: break;
            default: vpanic("getRegUsage_ARM:Call:regparms");
         }
         /* Finally, there is the issue that the insn trashes a
            register because the literal target address has to be
            loaded into a register.  Fortunately, for the nArgRegs=
            0/1/2/3 case, we can use r0, r1, r2 or r3 respectively, so
            this does not cause any further damage.  For the
            nArgRegs=4 case, we'll have to choose another register
            arbitrarily since all the caller saved regs are used for
            parameters, and so we might as well choose r11.
            */
         if (i->ARMin.Call.nArgRegs == 4)
            addHRegUse(u, HRmWrite, hregARM_R11());
         /* Upshot of this is that the assembler really must observe
            the here-stated convention of which register to use as an
            address temporary, depending on nArgRegs: 0==r0,
            1==r1, 2==r2, 3==r3, 4==r11 */
         return;
      case ARMin_Mul:
         addHRegUse(u, HRmRead, hregARM_R2());
         addHRegUse(u, HRmRead, hregARM_R3());
         addHRegUse(u, HRmWrite, hregARM_R0());
         if (i->ARMin.Mul.op != ARMmul_PLAIN)
            addHRegUse(u, HRmWrite, hregARM_R1());
         return;
      case ARMin_LdrEX:
         addHRegUse(u, HRmRead, hregARM_R4());
         addHRegUse(u, HRmWrite, hregARM_R2());
         if (i->ARMin.LdrEX.szB == 8)
            addHRegUse(u, HRmWrite, hregARM_R3());
         return;
      case ARMin_StrEX:
         addHRegUse(u, HRmRead, hregARM_R4());
         addHRegUse(u, HRmWrite, hregARM_R0());
         addHRegUse(u, HRmRead, hregARM_R2());
         if (i->ARMin.StrEX.szB == 8)
            addHRegUse(u, HRmRead, hregARM_R3());
         return;
      case ARMin_VLdStD:
         addRegUsage_ARMAModeV(u, i->ARMin.VLdStD.amode);
         if (i->ARMin.VLdStD.isLoad) {
            addHRegUse(u, HRmWrite, i->ARMin.VLdStD.dD);
         } else {
            addHRegUse(u, HRmRead, i->ARMin.VLdStD.dD);
         }
         return;
      case ARMin_VLdStS:
         addRegUsage_ARMAModeV(u, i->ARMin.VLdStS.amode);
         if (i->ARMin.VLdStS.isLoad) {
            addHRegUse(u, HRmWrite, i->ARMin.VLdStS.fD);
         } else {
            addHRegUse(u, HRmRead, i->ARMin.VLdStS.fD);
         }
         return;
      case ARMin_VAluD:
         addHRegUse(u, HRmWrite, i->ARMin.VAluD.dst);
         addHRegUse(u, HRmRead, i->ARMin.VAluD.argL);
         addHRegUse(u, HRmRead, i->ARMin.VAluD.argR);
         return;
      case ARMin_VAluS:
         addHRegUse(u, HRmWrite, i->ARMin.VAluS.dst);
         addHRegUse(u, HRmRead, i->ARMin.VAluS.argL);
         addHRegUse(u, HRmRead, i->ARMin.VAluS.argR);
         return;
      case ARMin_VUnaryD:
         addHRegUse(u, HRmWrite, i->ARMin.VUnaryD.dst);
         addHRegUse(u, HRmRead, i->ARMin.VUnaryD.src);
         return;
      case ARMin_VUnaryS:
         addHRegUse(u, HRmWrite, i->ARMin.VUnaryS.dst);
         addHRegUse(u, HRmRead, i->ARMin.VUnaryS.src);
         return;
      case ARMin_VCmpD:
         addHRegUse(u, HRmRead, i->ARMin.VCmpD.argL);
         addHRegUse(u, HRmRead, i->ARMin.VCmpD.argR);
         return;
      case ARMin_VCMovD:
         addHRegUse(u, HRmWrite, i->ARMin.VCMovD.dst);
         addHRegUse(u, HRmRead,  i->ARMin.VCMovD.dst);
         addHRegUse(u, HRmRead,  i->ARMin.VCMovD.src);
         return;
      case ARMin_VCMovS:
         addHRegUse(u, HRmWrite, i->ARMin.VCMovS.dst);
         addHRegUse(u, HRmRead,  i->ARMin.VCMovS.dst);
         addHRegUse(u, HRmRead,  i->ARMin.VCMovS.src);
         return;
      case ARMin_VCvtSD:
         addHRegUse(u, HRmWrite, i->ARMin.VCvtSD.dst);
         addHRegUse(u, HRmRead,  i->ARMin.VCvtSD.src);
         return;
      case ARMin_VXferD:
         if (i->ARMin.VXferD.toD) {
            addHRegUse(u, HRmWrite, i->ARMin.VXferD.dD);
            addHRegUse(u, HRmRead,  i->ARMin.VXferD.rHi);
            addHRegUse(u, HRmRead,  i->ARMin.VXferD.rLo);
         } else {
            addHRegUse(u, HRmRead,  i->ARMin.VXferD.dD);
            addHRegUse(u, HRmWrite, i->ARMin.VXferD.rHi);
            addHRegUse(u, HRmWrite, i->ARMin.VXferD.rLo);
         }
         return;
      case ARMin_VXferS:
         if (i->ARMin.VXferS.toS) {
            addHRegUse(u, HRmWrite, i->ARMin.VXferS.fD);
            addHRegUse(u, HRmRead,  i->ARMin.VXferS.rLo);
         } else {
            addHRegUse(u, HRmRead,  i->ARMin.VXferS.fD);
            addHRegUse(u, HRmWrite, i->ARMin.VXferS.rLo);
         }
         return;
      case ARMin_VCvtID:
         addHRegUse(u, HRmWrite, i->ARMin.VCvtID.dst);
         addHRegUse(u, HRmRead,  i->ARMin.VCvtID.src);
         return;
      case ARMin_FPSCR:
         if (i->ARMin.FPSCR.toFPSCR)
            addHRegUse(u, HRmRead, i->ARMin.FPSCR.iReg);
         else
            addHRegUse(u, HRmWrite, i->ARMin.FPSCR.iReg);
         return;
      case ARMin_MFence:
         return;
      case ARMin_CLREX:
         return;
      case ARMin_NLdStQ:
         if (i->ARMin.NLdStQ.isLoad)
            addHRegUse(u, HRmWrite, i->ARMin.NLdStQ.dQ);
         else
            addHRegUse(u, HRmRead, i->ARMin.NLdStQ.dQ);
         addRegUsage_ARMAModeN(u, i->ARMin.NLdStQ.amode);
         return;
      case ARMin_NLdStD:
         if (i->ARMin.NLdStD.isLoad)
            addHRegUse(u, HRmWrite, i->ARMin.NLdStD.dD);
         else
            addHRegUse(u, HRmRead, i->ARMin.NLdStD.dD);
         addRegUsage_ARMAModeN(u, i->ARMin.NLdStD.amode);
         return;
      case ARMin_NUnary:
         addHRegUse(u, HRmWrite, i->ARMin.NUnary.dst);
         addHRegUse(u, HRmRead, i->ARMin.NUnary.src);
         return;
      case ARMin_NUnaryS:
         addHRegUse(u, HRmWrite, i->ARMin.NUnaryS.dst->reg);
         addHRegUse(u, HRmRead, i->ARMin.NUnaryS.src->reg);
         return;
      case ARMin_NShift:
         addHRegUse(u, HRmWrite, i->ARMin.NShift.dst);
         addHRegUse(u, HRmRead, i->ARMin.NShift.argL);
         addHRegUse(u, HRmRead, i->ARMin.NShift.argR);
         return;
      case ARMin_NShl64:
         addHRegUse(u, HRmWrite, i->ARMin.NShl64.dst);
         addHRegUse(u, HRmRead, i->ARMin.NShl64.src);
         return;
      case ARMin_NDual:
         addHRegUse(u, HRmWrite, i->ARMin.NDual.arg1);
         addHRegUse(u, HRmWrite, i->ARMin.NDual.arg2);
         addHRegUse(u, HRmRead, i->ARMin.NDual.arg1);
         addHRegUse(u, HRmRead, i->ARMin.NDual.arg2);
         return;
      case ARMin_NBinary:
         addHRegUse(u, HRmWrite, i->ARMin.NBinary.dst);
         /* TODO: sometimes dst is also being read! */
         // XXX fix this
         addHRegUse(u, HRmRead, i->ARMin.NBinary.argL);
         addHRegUse(u, HRmRead, i->ARMin.NBinary.argR);
         return;
      case ARMin_NeonImm:
         addHRegUse(u, HRmWrite, i->ARMin.NeonImm.dst);
         return;
      case ARMin_NCMovQ:
         addHRegUse(u, HRmWrite, i->ARMin.NCMovQ.dst);
         addHRegUse(u, HRmRead,  i->ARMin.NCMovQ.dst);
         addHRegUse(u, HRmRead,  i->ARMin.NCMovQ.src);
         return;
      case ARMin_Add32:
         addHRegUse(u, HRmWrite, i->ARMin.Add32.rD);
         addHRegUse(u, HRmRead, i->ARMin.Add32.rN);
         return;
      case ARMin_EvCheck:
         /* We expect both amodes only to mention r8, so this is in
            fact pointless, since r8 isn't allocatable, but
            anyway.. */
         addRegUsage_ARMAMode1(u, i->ARMin.EvCheck.amCounter);
         addRegUsage_ARMAMode1(u, i->ARMin.EvCheck.amFailAddr);
         addHRegUse(u, HRmWrite, hregARM_R12()); /* also unavail to RA */
         return;
      case ARMin_ProfInc:
         addHRegUse(u, HRmWrite, hregARM_R12());
         addHRegUse(u, HRmWrite, hregARM_R11());
         return;
      default:
         ppARMInstr(i);
         vpanic("getRegUsage_ARMInstr");
   }
}


void mapRegs_ARMInstr ( HRegRemap* m, ARMInstr* i, Bool mode64 )
{
   vassert(mode64 == False);
   switch (i->tag) {
      case ARMin_Alu:
         i->ARMin.Alu.dst = lookupHRegRemap(m, i->ARMin.Alu.dst);
         i->ARMin.Alu.argL = lookupHRegRemap(m, i->ARMin.Alu.argL);
         mapRegs_ARMRI84(m, i->ARMin.Alu.argR);
         return;
      case ARMin_Shift:
         i->ARMin.Shift.dst = lookupHRegRemap(m, i->ARMin.Shift.dst);
         i->ARMin.Shift.argL = lookupHRegRemap(m, i->ARMin.Shift.argL);
         mapRegs_ARMRI5(m, i->ARMin.Shift.argR);
         return;
      case ARMin_Unary:
         i->ARMin.Unary.dst = lookupHRegRemap(m, i->ARMin.Unary.dst);
         i->ARMin.Unary.src = lookupHRegRemap(m, i->ARMin.Unary.src);
         return;
      case ARMin_CmpOrTst:
         i->ARMin.CmpOrTst.argL = lookupHRegRemap(m, i->ARMin.CmpOrTst.argL);
         mapRegs_ARMRI84(m, i->ARMin.CmpOrTst.argR);
         return;
      case ARMin_Mov:
         i->ARMin.Mov.dst = lookupHRegRemap(m, i->ARMin.Mov.dst);
         mapRegs_ARMRI84(m, i->ARMin.Mov.src);
         return;
      case ARMin_Imm32:
         i->ARMin.Imm32.dst = lookupHRegRemap(m, i->ARMin.Imm32.dst);
         return;
      case ARMin_LdSt32:
         i->ARMin.LdSt32.rD = lookupHRegRemap(m, i->ARMin.LdSt32.rD);
         mapRegs_ARMAMode1(m, i->ARMin.LdSt32.amode);
         return;
      case ARMin_LdSt16:
         i->ARMin.LdSt16.rD = lookupHRegRemap(m, i->ARMin.LdSt16.rD);
         mapRegs_ARMAMode2(m, i->ARMin.LdSt16.amode);
         return;
      case ARMin_LdSt8U:
         i->ARMin.LdSt8U.rD = lookupHRegRemap(m, i->ARMin.LdSt8U.rD);
         mapRegs_ARMAMode1(m, i->ARMin.LdSt8U.amode);
         return;
      case ARMin_Ld8S:
         i->ARMin.Ld8S.rD = lookupHRegRemap(m, i->ARMin.Ld8S.rD);
         mapRegs_ARMAMode2(m, i->ARMin.Ld8S.amode);
         return;
      case ARMin_XDirect:
         mapRegs_ARMAMode1(m, i->ARMin.XDirect.amR15T);
         return;
      case ARMin_XIndir:
         i->ARMin.XIndir.dstGA
            = lookupHRegRemap(m, i->ARMin.XIndir.dstGA);
         mapRegs_ARMAMode1(m, i->ARMin.XIndir.amR15T);
         return;
      case ARMin_XAssisted:
         i->ARMin.XAssisted.dstGA
            = lookupHRegRemap(m, i->ARMin.XAssisted.dstGA);
         mapRegs_ARMAMode1(m, i->ARMin.XAssisted.amR15T);
         return;
      case ARMin_CMov:
         i->ARMin.CMov.dst = lookupHRegRemap(m, i->ARMin.CMov.dst);
         mapRegs_ARMRI84(m, i->ARMin.CMov.src);
         return;
      case ARMin_Call:
         return;
      case ARMin_Mul:
         return;
      case ARMin_LdrEX:
         return;
      case ARMin_StrEX:
         return;
      case ARMin_VLdStD:
         i->ARMin.VLdStD.dD = lookupHRegRemap(m, i->ARMin.VLdStD.dD);
         mapRegs_ARMAModeV(m, i->ARMin.VLdStD.amode);
         return;
      case ARMin_VLdStS:
         i->ARMin.VLdStS.fD = lookupHRegRemap(m, i->ARMin.VLdStS.fD);
         mapRegs_ARMAModeV(m, i->ARMin.VLdStS.amode);
         return;
      case ARMin_VAluD:
         i->ARMin.VAluD.dst  = lookupHRegRemap(m, i->ARMin.VAluD.dst);
         i->ARMin.VAluD.argL = lookupHRegRemap(m, i->ARMin.VAluD.argL);
         i->ARMin.VAluD.argR = lookupHRegRemap(m, i->ARMin.VAluD.argR);
         return;
      case ARMin_VAluS:
         i->ARMin.VAluS.dst  = lookupHRegRemap(m, i->ARMin.VAluS.dst);
         i->ARMin.VAluS.argL = lookupHRegRemap(m, i->ARMin.VAluS.argL);
         i->ARMin.VAluS.argR = lookupHRegRemap(m, i->ARMin.VAluS.argR);
         return;
      case ARMin_VUnaryD:
         i->ARMin.VUnaryD.dst = lookupHRegRemap(m, i->ARMin.VUnaryD.dst);
         i->ARMin.VUnaryD.src = lookupHRegRemap(m, i->ARMin.VUnaryD.src);
         return;
      case ARMin_VUnaryS:
         i->ARMin.VUnaryS.dst = lookupHRegRemap(m, i->ARMin.VUnaryS.dst);
         i->ARMin.VUnaryS.src = lookupHRegRemap(m, i->ARMin.VUnaryS.src);
         return;
      case ARMin_VCmpD:
         i->ARMin.VCmpD.argL = lookupHRegRemap(m, i->ARMin.VCmpD.argL);
         i->ARMin.VCmpD.argR = lookupHRegRemap(m, i->ARMin.VCmpD.argR);
         return;
      case ARMin_VCMovD:
         i->ARMin.VCMovD.dst = lookupHRegRemap(m, i->ARMin.VCMovD.dst);
         i->ARMin.VCMovD.src = lookupHRegRemap(m, i->ARMin.VCMovD.src);
         return;
      case ARMin_VCMovS:
         i->ARMin.VCMovS.dst = lookupHRegRemap(m, i->ARMin.VCMovS.dst);
         i->ARMin.VCMovS.src = lookupHRegRemap(m, i->ARMin.VCMovS.src);
         return;
      case ARMin_VCvtSD:
         i->ARMin.VCvtSD.dst = lookupHRegRemap(m, i->ARMin.VCvtSD.dst);
         i->ARMin.VCvtSD.src = lookupHRegRemap(m, i->ARMin.VCvtSD.src);
         return;
      case ARMin_VXferD:
         i->ARMin.VXferD.dD  = lookupHRegRemap(m, i->ARMin.VXferD.dD);
         i->ARMin.VXferD.rHi = lookupHRegRemap(m, i->ARMin.VXferD.rHi);
         i->ARMin.VXferD.rLo = lookupHRegRemap(m, i->ARMin.VXferD.rLo);
         return;
      case ARMin_VXferS:
         i->ARMin.VXferS.fD  = lookupHRegRemap(m, i->ARMin.VXferS.fD);
         i->ARMin.VXferS.rLo = lookupHRegRemap(m, i->ARMin.VXferS.rLo);
         return;
      case ARMin_VCvtID:
         i->ARMin.VCvtID.dst = lookupHRegRemap(m, i->ARMin.VCvtID.dst);
         i->ARMin.VCvtID.src = lookupHRegRemap(m, i->ARMin.VCvtID.src);
         return;
      case ARMin_FPSCR:
         i->ARMin.FPSCR.iReg = lookupHRegRemap(m, i->ARMin.FPSCR.iReg);
         return;
      case ARMin_MFence:
         return;
      case ARMin_CLREX:
         return;
      case ARMin_NLdStQ:
         i->ARMin.NLdStQ.dQ = lookupHRegRemap(m, i->ARMin.NLdStQ.dQ);
         mapRegs_ARMAModeN(m, i->ARMin.NLdStQ.amode);
         return;
      case ARMin_NLdStD:
         i->ARMin.NLdStD.dD = lookupHRegRemap(m, i->ARMin.NLdStD.dD);
         mapRegs_ARMAModeN(m, i->ARMin.NLdStD.amode);
         return;
      case ARMin_NUnary:
         i->ARMin.NUnary.src = lookupHRegRemap(m, i->ARMin.NUnary.src);
         i->ARMin.NUnary.dst = lookupHRegRemap(m, i->ARMin.NUnary.dst);
         return;
      case ARMin_NUnaryS:
         i->ARMin.NUnaryS.src->reg
            = lookupHRegRemap(m, i->ARMin.NUnaryS.src->reg);
         i->ARMin.NUnaryS.dst->reg
            = lookupHRegRemap(m, i->ARMin.NUnaryS.dst->reg);
         return;
      case ARMin_NShift:
         i->ARMin.NShift.dst = lookupHRegRemap(m, i->ARMin.NShift.dst);
         i->ARMin.NShift.argL = lookupHRegRemap(m, i->ARMin.NShift.argL);
         i->ARMin.NShift.argR = lookupHRegRemap(m, i->ARMin.NShift.argR);
         return;
      case ARMin_NShl64:
         i->ARMin.NShl64.dst = lookupHRegRemap(m, i->ARMin.NShl64.dst);
         i->ARMin.NShl64.src = lookupHRegRemap(m, i->ARMin.NShl64.src);
         return;
      case ARMin_NDual:
         i->ARMin.NDual.arg1 = lookupHRegRemap(m, i->ARMin.NDual.arg1);
         i->ARMin.NDual.arg2 = lookupHRegRemap(m, i->ARMin.NDual.arg2);
         return;
      case ARMin_NBinary:
         i->ARMin.NBinary.argL = lookupHRegRemap(m, i->ARMin.NBinary.argL);
         i->ARMin.NBinary.argR = lookupHRegRemap(m, i->ARMin.NBinary.argR);
         i->ARMin.NBinary.dst  = lookupHRegRemap(m, i->ARMin.NBinary.dst);
         return;
      case ARMin_NeonImm:
         i->ARMin.NeonImm.dst = lookupHRegRemap(m, i->ARMin.NeonImm.dst);
         return;
      case ARMin_NCMovQ:
         i->ARMin.NCMovQ.dst = lookupHRegRemap(m, i->ARMin.NCMovQ.dst);
         i->ARMin.NCMovQ.src = lookupHRegRemap(m, i->ARMin.NCMovQ.src);
         return;
      case ARMin_Add32:
         i->ARMin.Add32.rD = lookupHRegRemap(m, i->ARMin.Add32.rD);
         i->ARMin.Add32.rN = lookupHRegRemap(m, i->ARMin.Add32.rN);
         return;
      case ARMin_EvCheck:
         /* We expect both amodes only to mention r8, so this is in
            fact pointless, since r8 isn't allocatable, but
            anyway.. */
         mapRegs_ARMAMode1(m, i->ARMin.EvCheck.amCounter);
         mapRegs_ARMAMode1(m, i->ARMin.EvCheck.amFailAddr);
         return;
      case ARMin_ProfInc:
         /* hardwires r11 and r12 -- nothing to modify. */
         return;
      default:
         ppARMInstr(i);
         vpanic("mapRegs_ARMInstr");
   }
}

/* Figure out if i represents a reg-reg move, and if so assign the
   source and destination to *src and *dst.  If in doubt say No.  Used
   by the register allocator to do move coalescing.
*/
Bool isMove_ARMInstr ( ARMInstr* i, HReg* src, HReg* dst )
{
   /* Moves between integer regs */
   switch (i->tag) {
      case ARMin_Mov:
         if (i->ARMin.Mov.src->tag == ARMri84_R) {
            *src = i->ARMin.Mov.src->ARMri84.R.reg;
            *dst = i->ARMin.Mov.dst;
            return True;
         }
         break;
      case ARMin_VUnaryD:
         if (i->ARMin.VUnaryD.op == ARMvfpu_COPY) {
            *src = i->ARMin.VUnaryD.src;
            *dst = i->ARMin.VUnaryD.dst;
            return True;
         }
         break;
      case ARMin_VUnaryS:
         if (i->ARMin.VUnaryS.op == ARMvfpu_COPY) {
            *src = i->ARMin.VUnaryS.src;
            *dst = i->ARMin.VUnaryS.dst;
            return True;
         }
         break;
      case ARMin_NUnary:
         if (i->ARMin.NUnary.op == ARMneon_COPY) {
            *src = i->ARMin.NUnary.src;
            *dst = i->ARMin.NUnary.dst;
            return True;
         }
         break;
      default:
         break;
   }

   return False;
}


/* Generate arm spill/reload instructions under the direction of the
   register allocator.  Note it's critical these don't write the
   condition codes. */

void genSpill_ARM ( /*OUT*/HInstr** i1, /*OUT*/HInstr** i2,
                    HReg rreg, Int offsetB, Bool mode64 )
{
   HRegClass rclass;
   vassert(offsetB >= 0);
   vassert(!hregIsVirtual(rreg));
   vassert(mode64 == False);
   *i1 = *i2 = NULL;
   rclass = hregClass(rreg);
   switch (rclass) {
      case HRcInt32:
         vassert(offsetB <= 4095);
         *i1 = ARMInstr_LdSt32( ARMcc_AL, False/*!isLoad*/,
                                rreg,
                                ARMAMode1_RI(hregARM_R8(), offsetB) );
         return;
      case HRcFlt32:
      case HRcFlt64: {
         HReg r8   = hregARM_R8();  /* baseblock */
         HReg r12  = hregARM_R12(); /* spill temp */
         HReg base = r8;
         vassert(0 == (offsetB & 3));
         if (offsetB >= 1024) {
            Int offsetKB = offsetB / 1024;
            /* r12 = r8 + (1024 * offsetKB) */
            *i1 = ARMInstr_Alu(ARMalu_ADD, r12, r8,
                               ARMRI84_I84(offsetKB, 11));
            offsetB -= (1024 * offsetKB);
            base = r12;
         }
         vassert(offsetB <= 1020);
         if (rclass == HRcFlt32) {
            *i2 = ARMInstr_VLdStS( False/*!isLoad*/,
                                   rreg,
                                   mkARMAModeV(base, offsetB) );
         } else {
            *i2 = ARMInstr_VLdStD( False/*!isLoad*/,
                                   rreg,
                                   mkARMAModeV(base, offsetB) );
         }
         return;
      }
      case HRcVec128: {
         HReg r8  = hregARM_R8();
         HReg r12 = hregARM_R12();
         *i1 = ARMInstr_Add32(r12, r8, offsetB);
         *i2 = ARMInstr_NLdStQ(False, rreg, mkARMAModeN_R(r12));
         return;
      }
      default:
         ppHRegClass(rclass);
         vpanic("genSpill_ARM: unimplemented regclass");
   }
}

void genReload_ARM ( /*OUT*/HInstr** i1, /*OUT*/HInstr** i2,
                     HReg rreg, Int offsetB, Bool mode64 )
{
   HRegClass rclass;
   vassert(offsetB >= 0);
   vassert(!hregIsVirtual(rreg));
   vassert(mode64 == False);
   *i1 = *i2 = NULL;
   rclass = hregClass(rreg);
   switch (rclass) {
      case HRcInt32:
         vassert(offsetB <= 4095);
         *i1 = ARMInstr_LdSt32( ARMcc_AL, True/*isLoad*/,
                                rreg,
                                ARMAMode1_RI(hregARM_R8(), offsetB) );
         return;
      case HRcFlt32:
      case HRcFlt64: {
         HReg r8   = hregARM_R8();  /* baseblock */
         HReg r12  = hregARM_R12(); /* spill temp */
         HReg base = r8;
         vassert(0 == (offsetB & 3));
         if (offsetB >= 1024) {
            Int offsetKB = offsetB / 1024;
            /* r12 = r8 + (1024 * offsetKB) */
            *i1 = ARMInstr_Alu(ARMalu_ADD, r12, r8,
                               ARMRI84_I84(offsetKB, 11));
            offsetB -= (1024 * offsetKB);
            base = r12;
         }
         vassert(offsetB <= 1020);
         if (rclass == HRcFlt32) {
            *i2 = ARMInstr_VLdStS( True/*isLoad*/,
                                   rreg,
                                   mkARMAModeV(base, offsetB) );
         } else {
            *i2 = ARMInstr_VLdStD( True/*isLoad*/,
                                   rreg,
                                   mkARMAModeV(base, offsetB) );
         }
         return;
      }
      case HRcVec128: {
         HReg r8  = hregARM_R8();
         HReg r12 = hregARM_R12();
         *i1 = ARMInstr_Add32(r12, r8, offsetB);
         *i2 = ARMInstr_NLdStQ(True, rreg, mkARMAModeN_R(r12));
         return;
      }
      default:
         ppHRegClass(rclass);
         vpanic("genReload_ARM: unimplemented regclass");
   }
}


/* Emit an instruction into buf and return the number of bytes used.
   Note that buf is not the insn's final place, and therefore it is
   imperative to emit position-independent code. */

static inline UChar iregNo ( HReg r )
{
   UInt n;
   vassert(hregClass(r) == HRcInt32);
   vassert(!hregIsVirtual(r));
   n = hregNumber(r);
   vassert(n <= 15);
   return toUChar(n);
}

static inline UChar dregNo ( HReg r )
{
   UInt n;
   if (hregClass(r) != HRcFlt64)
      ppHRegClass(hregClass(r));
   vassert(hregClass(r) == HRcFlt64);
   vassert(!hregIsVirtual(r));
   n = hregNumber(r);
   vassert(n <= 31);
   return toUChar(n);
}

static inline UChar fregNo ( HReg r )
{
   UInt n;
   vassert(hregClass(r) == HRcFlt32);
   vassert(!hregIsVirtual(r));
   n = hregNumber(r);
   vassert(n <= 31);
   return toUChar(n);
}

static inline UChar qregNo ( HReg r )
{
   UInt n;
   vassert(hregClass(r) == HRcVec128);
   vassert(!hregIsVirtual(r));
   n = hregNumber(r);
   vassert(n <= 15);
   return toUChar(n);
}

#define BITS4(zzb3,zzb2,zzb1,zzb0) \
   (((zzb3) << 3) | ((zzb2) << 2) | ((zzb1) << 1) | (zzb0))
#define X0000  BITS4(0,0,0,0)
#define X0001  BITS4(0,0,0,1)
#define X0010  BITS4(0,0,1,0)
#define X0011  BITS4(0,0,1,1)
#define X0100  BITS4(0,1,0,0)
#define X0101  BITS4(0,1,0,1)
#define X0110  BITS4(0,1,1,0)
#define X0111  BITS4(0,1,1,1)
#define X1000  BITS4(1,0,0,0)
#define X1001  BITS4(1,0,0,1)
#define X1010  BITS4(1,0,1,0)
#define X1011  BITS4(1,0,1,1)
#define X1100  BITS4(1,1,0,0)
#define X1101  BITS4(1,1,0,1)
#define X1110  BITS4(1,1,1,0)
#define X1111  BITS4(1,1,1,1)

#define XXXXX___(zzx7,zzx6,zzx5,zzx4,zzx3) \
   ((((zzx7) & 0xF) << 28) | (((zzx6) & 0xF) << 24) |  \
    (((zzx5) & 0xF) << 20) | (((zzx4) & 0xF) << 16) |  \
    (((zzx3) & 0xF) << 12))

#define XXXXXX__(zzx7,zzx6,zzx5,zzx4,zzx3,zzx2)        \
   ((((zzx7) & 0xF) << 28) | (((zzx6) & 0xF) << 24) |  \
    (((zzx5) & 0xF) << 20) | (((zzx4) & 0xF) << 16) |  \
    (((zzx3) & 0xF) << 12) | (((zzx2) & 0xF) <<  8))

#define XXXXX__X(zzx7,zzx6,zzx5,zzx4,zzx3,zzx0)        \
   ((((zzx7) & 0xF) << 28) | (((zzx6) & 0xF) << 24) |  \
    (((zzx5) & 0xF) << 20) | (((zzx4) & 0xF) << 16) |  \
    (((zzx3) & 0xF) << 12) | (((zzx0) & 0xF) <<  0))

#define XXX___XX(zzx7,zzx6,zzx5,zzx1,zzx0) \
  ((((zzx7) & 0xF) << 28) | (((zzx6) & 0xF) << 24) | \
   (((zzx5) & 0xF) << 20) | (((zzx1) & 0xF) << 4) | \
   (((zzx0) & 0xF) << 0))

#define XXXXXXXX(zzx7,zzx6,zzx5,zzx4,zzx3,zzx2,zzx1,zzx0)  \
   ((((zzx7) & 0xF) << 28) | (((zzx6) & 0xF) << 24) |  \
    (((zzx5) & 0xF) << 20) | (((zzx4) & 0xF) << 16) |  \
    (((zzx3) & 0xF) << 12) | (((zzx2) & 0xF) <<  8) |  \
    (((zzx1) & 0xF) <<  4) | (((zzx0) & 0xF) <<  0))

#define XX______(zzx7,zzx6) \
   ((((zzx7) & 0xF) << 28) | (((zzx6) & 0xF) << 24))

/* Generate a skeletal insn that involves an a RI84 shifter operand.
   Returns a word which is all zeroes apart from bits 25 and 11..0,
   since it is those that encode the shifter operand (at least to the
   extent that we care about it.) */
static UInt skeletal_RI84 ( ARMRI84* ri )
{
   UInt instr;
   if (ri->tag == ARMri84_I84) {
      vassert(0 == (ri->ARMri84.I84.imm4 & ~0x0F));
      vassert(0 == (ri->ARMri84.I84.imm8 & ~0xFF));
      instr = 1 << 25;
      instr |= (ri->ARMri84.I84.imm4 << 8);
      instr |= ri->ARMri84.I84.imm8;
   } else {
      instr = 0 << 25;
      instr |= iregNo(ri->ARMri84.R.reg);
   }
   return instr;
}

/* Ditto for RI5.  Resulting word is zeroes apart from bit 4 and bits
   11..7. */
static UInt skeletal_RI5 ( ARMRI5* ri )
{
   UInt instr;
   if (ri->tag == ARMri5_I5) {
      UInt imm5 = ri->ARMri5.I5.imm5;
      vassert(imm5 >= 1 && imm5 <= 31);
      instr = 0 << 4;
      instr |= imm5 << 7;
   } else {
      instr = 1 << 4;
      instr |= iregNo(ri->ARMri5.R.reg) << 8;
   }
   return instr;
}


/* Get an immediate into a register, using only that
   register.  (very lame..) */
static UInt* imm32_to_iregNo ( UInt* p, Int rD, UInt imm32 )
{
   UInt instr;
   vassert(rD >= 0 && rD <= 14); // r15 not good to mess with!
#if 0
   if (0 == (imm32 & ~0xFF)) {
      /* mov with a immediate shifter operand of (0, imm32) (??) */
      instr = XXXXXX__(X1110,X0011,X1010,X0000,rD,X0000);
      instr |= imm32;
      *p++ = instr;
   } else {
      // this is very bad; causes Dcache pollution
      // ldr  rD, [pc]
      instr = XXXXX___(X1110,X0101,X1001,X1111,rD);
      *p++ = instr;
      // b .+8
      instr = 0xEA000000;
      *p++ = instr;
      // .word imm32
      *p++ = imm32;
   }
#else
   if (VEX_ARM_ARCHLEVEL(arm_hwcaps) > 6) {
      /* Generate movw rD, #low16.  Then, if the high 16 are
         nonzero, generate movt rD, #high16. */
      UInt lo16 = imm32 & 0xFFFF;
      UInt hi16 = (imm32 >> 16) & 0xFFFF;
      instr = XXXXXXXX(0xE, 0x3, 0x0, (lo16 >> 12) & 0xF, rD,
                       (lo16 >> 8) & 0xF, (lo16 >> 4) & 0xF,
                       lo16 & 0xF);
      *p++ = instr;
      if (hi16 != 0) {
         instr = XXXXXXXX(0xE, 0x3, 0x4, (hi16 >> 12) & 0xF, rD,
                          (hi16 >> 8) & 0xF, (hi16 >> 4) & 0xF,
                          hi16 & 0xF);
         *p++ = instr;
      }
   } else {
      UInt imm, rot;
      UInt op = X1010;
      UInt rN = 0;
      if ((imm32 & 0xFF) || (imm32 == 0)) {
         imm = imm32 & 0xFF;
         rot = 0;
         instr = XXXXXXXX(0xE, 0x3, op, rN, rD, rot, imm >> 4, imm & 0xF);
         *p++ = instr;
         op = X1000;
         rN = rD;
      }
      if (imm32 & 0xFF000000) {
         imm = (imm32 >> 24) & 0xFF;
         rot = 4;
         instr = XXXXXXXX(0xE, 0x3, op, rN, rD, rot, imm >> 4, imm & 0xF);
         *p++ = instr;
         op = X1000;
         rN = rD;
      }
      if (imm32 & 0xFF0000) {
         imm = (imm32 >> 16) & 0xFF;
         rot = 8;
         instr = XXXXXXXX(0xE, 0x3, op, rN, rD, rot, imm >> 4, imm & 0xF);
         *p++ = instr;
         op = X1000;
         rN = rD;
      }
      if (imm32 & 0xFF00) {
         imm = (imm32 >> 8) & 0xFF;
         rot = 12;
         instr = XXXXXXXX(0xE, 0x3, op, rN, rD, rot, imm >> 4, imm & 0xF);
         *p++ = instr;
         op = X1000;
         rN = rD;
      }
   }
#endif
   return p;
}

/* Get an immediate into a register, using only that register, and
   generating exactly 2 instructions, regardless of the value of the
   immediate. This is used when generating sections of code that need
   to be patched later, so as to guarantee a specific size. */
static UInt* imm32_to_iregNo_EXACTLY2 ( UInt* p, Int rD, UInt imm32 )
{
   if (VEX_ARM_ARCHLEVEL(arm_hwcaps) > 6) {
      /* Generate movw rD, #low16 ;  movt rD, #high16. */
      UInt lo16 = imm32 & 0xFFFF;
      UInt hi16 = (imm32 >> 16) & 0xFFFF;
      UInt instr;
      instr = XXXXXXXX(0xE, 0x3, 0x0, (lo16 >> 12) & 0xF, rD,
                       (lo16 >> 8) & 0xF, (lo16 >> 4) & 0xF,
                       lo16 & 0xF);
      *p++ = instr;
      instr = XXXXXXXX(0xE, 0x3, 0x4, (hi16 >> 12) & 0xF, rD,
                       (hi16 >> 8) & 0xF, (hi16 >> 4) & 0xF,
                       hi16 & 0xF);
      *p++ = instr;
   } else {
      vassert(0); /* lose */
   }
   return p;
}

/* Check whether p points at a 2-insn sequence cooked up by
   imm32_to_iregNo_EXACTLY2(). */
static Bool is_imm32_to_iregNo_EXACTLY2 ( UInt* p, Int rD, UInt imm32 )
{
   if (VEX_ARM_ARCHLEVEL(arm_hwcaps) > 6) {
      /* Generate movw rD, #low16 ;  movt rD, #high16. */
      UInt lo16 = imm32 & 0xFFFF;
      UInt hi16 = (imm32 >> 16) & 0xFFFF;
      UInt i0, i1;
      i0 = XXXXXXXX(0xE, 0x3, 0x0, (lo16 >> 12) & 0xF, rD,
                    (lo16 >> 8) & 0xF, (lo16 >> 4) & 0xF,
                    lo16 & 0xF);
      i1 = XXXXXXXX(0xE, 0x3, 0x4, (hi16 >> 12) & 0xF, rD,
                    (hi16 >> 8) & 0xF, (hi16 >> 4) & 0xF,
                    hi16 & 0xF);
      return p[0] == i0 && p[1] == i1;
   } else {
      vassert(0); /* lose */
   }
}


static UInt* do_load_or_store32 ( UInt* p,
                                  Bool isLoad, UInt rD, ARMAMode1* am )
{
   vassert(rD <= 12);
   vassert(am->tag == ARMam1_RI); // RR case is not handled
   UInt bB = 0;
   UInt bL = isLoad ? 1 : 0;
   Int  simm12;
   UInt instr, bP;
   if (am->ARMam1.RI.simm13 < 0) {
      bP = 0;
      simm12 = -am->ARMam1.RI.simm13;
   } else {
      bP = 1;
      simm12 = am->ARMam1.RI.simm13;
   }
   vassert(simm12 >= 0 && simm12 <= 4095);
   instr = XXXXX___(X1110,X0101,BITS4(bP,bB,0,bL),
                    iregNo(am->ARMam1.RI.reg),
                    rD);
   instr |= simm12;
   *p++ = instr;
   return p;
}


/* Emit an instruction into buf and return the number of bytes used.
   Note that buf is not the insn's final place, and therefore it is
   imperative to emit position-independent code.  If the emitted
   instruction was a profiler inc, set *is_profInc to True, else
   leave it unchanged. */

Int emit_ARMInstr ( /*MB_MOD*/Bool* is_profInc,
                    UChar* buf, Int nbuf, ARMInstr* i,
                    Bool mode64,
                    void* disp_cp_chain_me_to_slowEP,
                    void* disp_cp_chain_me_to_fastEP,
                    void* disp_cp_xindir,
                    void* disp_cp_xassisted )
{
   UInt* p = (UInt*)buf;
   vassert(nbuf >= 32);
   vassert(mode64 == False);
   vassert(0 == (((HWord)buf) & 3));

   switch (i->tag) {
      case ARMin_Alu: {
         UInt     instr, subopc;
         UInt     rD   = iregNo(i->ARMin.Alu.dst);
         UInt     rN   = iregNo(i->ARMin.Alu.argL);
         ARMRI84* argR = i->ARMin.Alu.argR;
         switch (i->ARMin.Alu.op) {
            case ARMalu_ADDS: /* fallthru */
            case ARMalu_ADD:  subopc = X0100; break;
            case ARMalu_ADC:  subopc = X0101; break;
            case ARMalu_SUBS: /* fallthru */
            case ARMalu_SUB:  subopc = X0010; break;
            case ARMalu_SBC:  subopc = X0110; break;
            case ARMalu_AND:  subopc = X0000; break;
            case ARMalu_BIC:  subopc = X1110; break;
            case ARMalu_OR:   subopc = X1100; break;
            case ARMalu_XOR:  subopc = X0001; break;
            default: goto bad;
         }
         instr = skeletal_RI84(argR);
         instr |= XXXXX___(X1110, (1 & (subopc >> 3)),
                           (subopc << 1) & 0xF, rN, rD);
         if (i->ARMin.Alu.op == ARMalu_ADDS
             || i->ARMin.Alu.op == ARMalu_SUBS) {
            instr |= 1<<20;  /* set the S bit */
         }
         *p++ = instr;
         goto done;
      }
      case ARMin_Shift: {
         UInt    instr, subopc;
         UInt    rD   = iregNo(i->ARMin.Shift.dst);
         UInt    rM   = iregNo(i->ARMin.Shift.argL);
         ARMRI5* argR = i->ARMin.Shift.argR;
         switch (i->ARMin.Shift.op) {
            case ARMsh_SHL: subopc = X0000; break;
            case ARMsh_SHR: subopc = X0001; break;
            case ARMsh_SAR: subopc = X0010; break;
            default: goto bad;
         }
         instr = skeletal_RI5(argR);
         instr |= XXXXX__X(X1110,X0001,X1010,X0000,rD, /* _ _ */ rM);
         instr |= (subopc & 3) << 5;
         *p++ = instr;
         goto done;
      }
      case ARMin_Unary: {
         UInt instr;
         UInt rDst = iregNo(i->ARMin.Unary.dst);
         UInt rSrc = iregNo(i->ARMin.Unary.src);
         switch (i->ARMin.Unary.op) {
            case ARMun_CLZ:
               instr = XXXXXXXX(X1110,X0001,X0110,X1111,
                                rDst,X1111,X0001,rSrc);
               *p++ = instr;
               goto done;
            case ARMun_NEG: /* RSB rD,rS,#0 */
               instr = XXXXX___(X1110,0x2,0x6,rSrc,rDst);
               *p++ = instr;
               goto done;
            case ARMun_NOT: {
               UInt subopc = X1111; /* MVN */
               instr = rSrc;
               instr |= XXXXX___(X1110, (1 & (subopc >> 3)),
                                 (subopc << 1) & 0xF, 0, rDst);
               *p++ = instr;
               goto done;
            }
            default:
               break;
         }
         goto bad;
      }
      case ARMin_CmpOrTst: {
         UInt instr  = skeletal_RI84(i->ARMin.CmpOrTst.argR);
         UInt subopc = i->ARMin.CmpOrTst.isCmp ? X1010 : X1000;
         UInt SBZ    = 0;
         instr |= XXXXX___(X1110, (1 & (subopc >> 3)),
                           ((subopc << 1) & 0xF) | 1,
                           iregNo(i->ARMin.CmpOrTst.argL), SBZ );
         *p++ = instr;
         goto done;
      }
      case ARMin_Mov: {
         UInt instr  = skeletal_RI84(i->ARMin.Mov.src);
         UInt subopc = X1101; /* MOV */
         UInt SBZ    = 0;
         instr |= XXXXX___(X1110, (1 & (subopc >> 3)),
                           (subopc << 1) & 0xF, SBZ,
                           iregNo(i->ARMin.Mov.dst));
         *p++ = instr;
         goto done;
      }
      case ARMin_Imm32: {
         p = imm32_to_iregNo( (UInt*)p, iregNo(i->ARMin.Imm32.dst),
                                        i->ARMin.Imm32.imm32 );
         goto done;
      }
      case ARMin_LdSt32:
      case ARMin_LdSt8U: {
         UInt        bL, bB;
         HReg        rD;
         ARMAMode1*  am;
         ARMCondCode cc;
         if (i->tag == ARMin_LdSt32) {
            bB = 0;
            bL = i->ARMin.LdSt32.isLoad ? 1 : 0;
            am = i->ARMin.LdSt32.amode;
            rD = i->ARMin.LdSt32.rD;
            cc = i->ARMin.LdSt32.cc;
         } else {
            bB = 1;
            bL = i->ARMin.LdSt8U.isLoad ? 1 : 0;
            am = i->ARMin.LdSt8U.amode;
            rD = i->ARMin.LdSt8U.rD;
            cc = i->ARMin.LdSt8U.cc;
         }
         vassert(cc != ARMcc_NV);
         if (am->tag == ARMam1_RI) {
            Int  simm12;
            UInt instr, bP;
            if (am->ARMam1.RI.simm13 < 0) {
               bP = 0;
               simm12 = -am->ARMam1.RI.simm13;
            } else {
               bP = 1;
               simm12 = am->ARMam1.RI.simm13;
            }
            vassert(simm12 >= 0 && simm12 <= 4095);
            instr = XXXXX___(cc,X0101,BITS4(bP,bB,0,bL),
                             iregNo(am->ARMam1.RI.reg),
                             iregNo(rD));
            instr |= simm12;
            *p++ = instr;
            goto done;
         } else {
            // RR case
            goto bad;
         }
      }
      case ARMin_LdSt16: {
         HReg        rD = i->ARMin.LdSt16.rD;
         UInt        bS = i->ARMin.LdSt16.signedLoad ? 1 : 0;
         UInt        bL = i->ARMin.LdSt16.isLoad ? 1 : 0;
         ARMAMode2*  am = i->ARMin.LdSt16.amode;
         ARMCondCode cc = i->ARMin.LdSt16.cc;
         vassert(cc != ARMcc_NV);
         if (am->tag == ARMam2_RI) {
            HReg rN = am->ARMam2.RI.reg;
            Int  simm8;
            UInt bP, imm8hi, imm8lo, instr;
            if (am->ARMam2.RI.simm9 < 0) {
               bP = 0;
               simm8 = -am->ARMam2.RI.simm9;
            } else {
               bP = 1;
               simm8 = am->ARMam2.RI.simm9;
            }
            vassert(simm8 >= 0 && simm8 <= 255);
            imm8hi = (simm8 >> 4) & 0xF;
            imm8lo = simm8 & 0xF;
            vassert(!(bL == 0 && bS == 1)); // "! signed store"
            /**/ if (bL == 0 && bS == 0) {
               // strh
               instr = XXXXXXXX(cc,X0001, BITS4(bP,1,0,0), iregNo(rN),
                                iregNo(rD), imm8hi, X1011, imm8lo);
               *p++ = instr;
               goto done;
            }
            else if (bL == 1 && bS == 0) {
               // ldrh
               instr = XXXXXXXX(cc,X0001, BITS4(bP,1,0,1), iregNo(rN),
                                iregNo(rD), imm8hi, X1011, imm8lo);
               *p++ = instr;
               goto done;
            }
            else if (bL == 1 && bS == 1) {
               // ldrsh
               instr = XXXXXXXX(cc,X0001, BITS4(bP,1,0,1), iregNo(rN),
                                iregNo(rD), imm8hi, X1111, imm8lo);
               *p++ = instr;
               goto done;
            }
            else vassert(0); // ill-constructed insn
         } else {
            // RR case
            goto bad;
         }
      }
      case ARMin_Ld8S: {
         HReg        rD = i->ARMin.Ld8S.rD;
         ARMAMode2*  am = i->ARMin.Ld8S.amode;
         ARMCondCode cc = i->ARMin.Ld8S.cc;
         vassert(cc != ARMcc_NV);
         if (am->tag == ARMam2_RI) {
            HReg rN = am->ARMam2.RI.reg;
            Int  simm8;
            UInt bP, imm8hi, imm8lo, instr;
            if (am->ARMam2.RI.simm9 < 0) {
               bP = 0;
               simm8 = -am->ARMam2.RI.simm9;
            } else {
               bP = 1;
               simm8 = am->ARMam2.RI.simm9;
            }
            vassert(simm8 >= 0 && simm8 <= 255);
            imm8hi = (simm8 >> 4) & 0xF;
            imm8lo = simm8 & 0xF;
            // ldrsb
            instr = XXXXXXXX(cc,X0001, BITS4(bP,1,0,1), iregNo(rN),
                             iregNo(rD), imm8hi, X1101, imm8lo);
            *p++ = instr;
            goto done;
         } else {
            // RR case
            goto bad;
         }
      }

      case ARMin_XDirect: {
         /* NB: what goes on here has to be very closely coordinated
            with the chainXDirect_ARM and unchainXDirect_ARM below. */
         /* We're generating chain-me requests here, so we need to be
            sure this is actually allowed -- no-redir translations
            can't use chain-me's.  Hence: */
         vassert(disp_cp_chain_me_to_slowEP != NULL);
         vassert(disp_cp_chain_me_to_fastEP != NULL);

         /* Use ptmp for backpatching conditional jumps. */
         UInt* ptmp = NULL;

         /* First off, if this is conditional, create a conditional
            jump over the rest of it.  Or at least, leave a space for
            it that we will shortly fill in. */
         if (i->ARMin.XDirect.cond != ARMcc_AL) {
            vassert(i->ARMin.XDirect.cond != ARMcc_NV);
            ptmp = p;
            *p++ = 0;
         }

         /* Update the guest R15T. */
         /* movw r12, lo16(dstGA) */
         /* movt r12, hi16(dstGA) */
         /* str r12, amR15T */
         p = imm32_to_iregNo(p, /*r*/12, i->ARMin.XDirect.dstGA);
         p = do_load_or_store32(p, False/*!isLoad*/,
                                /*r*/12, i->ARMin.XDirect.amR15T);

         /* --- FIRST PATCHABLE BYTE follows --- */
         /* VG_(disp_cp_chain_me_to_{slowEP,fastEP}) (where we're
            calling to) backs up the return address, so as to find the
            address of the first patchable byte.  So: don't change the
            number of instructions (3) below. */
         /* movw r12, lo16(VG_(disp_cp_chain_me_to_{slowEP,fastEP})) */
         /* movt r12, hi16(VG_(disp_cp_chain_me_to_{slowEP,fastEP})) */
         /* blx  r12  (A1) */
         void* disp_cp_chain_me
                  = i->ARMin.XDirect.toFastEP ? disp_cp_chain_me_to_fastEP
                                              : disp_cp_chain_me_to_slowEP;
         p = imm32_to_iregNo_EXACTLY2(p, /*r*/12,
                                      (UInt)Ptr_to_ULong(disp_cp_chain_me));
         *p++ = 0xE12FFF3C;
         /* --- END of PATCHABLE BYTES --- */

         /* Fix up the conditional jump, if there was one. */
         if (i->ARMin.XDirect.cond != ARMcc_AL) {
            Int delta = (UChar*)p - (UChar*)ptmp; /* must be signed */
            vassert(delta > 0 && delta < 40);
            vassert((delta & 3) == 0);
            UInt notCond = 1 ^ (UInt)i->ARMin.XDirect.cond;
            vassert(notCond <= 13); /* Neither AL nor NV */
            delta = (delta >> 2) - 2;
            *ptmp = XX______(notCond, X1010) | (delta & 0xFFFFFF);
         }
         goto done;
      }

      case ARMin_XIndir: {
         /* We're generating transfers that could lead indirectly to a
            chain-me, so we need to be sure this is actually allowed
            -- no-redir translations are not allowed to reach normal
            translations without going through the scheduler.  That
            means no XDirects or XIndirs out from no-redir
            translations.  Hence: */
         vassert(disp_cp_xindir != NULL);

         /* Use ptmp for backpatching conditional jumps. */
         UInt* ptmp = NULL;

         /* First off, if this is conditional, create a conditional
            jump over the rest of it.  Or at least, leave a space for
            it that we will shortly fill in. */
         if (i->ARMin.XIndir.cond != ARMcc_AL) {
            vassert(i->ARMin.XIndir.cond != ARMcc_NV);
            ptmp = p;
            *p++ = 0;
         }

         /* Update the guest R15T. */
         /* str r-dstGA, amR15T */
         p = do_load_or_store32(p, False/*!isLoad*/,
                                iregNo(i->ARMin.XIndir.dstGA),
                                i->ARMin.XIndir.amR15T);

         /* movw r12, lo16(VG_(disp_cp_xindir)) */
         /* movt r12, hi16(VG_(disp_cp_xindir)) */
         /* bx   r12  (A1) */
         p = imm32_to_iregNo(p, /*r*/12,
                             (UInt)Ptr_to_ULong(disp_cp_xindir));
         *p++ = 0xE12FFF1C;

         /* Fix up the conditional jump, if there was one. */
         if (i->ARMin.XIndir.cond != ARMcc_AL) {
            Int delta = (UChar*)p - (UChar*)ptmp; /* must be signed */
            vassert(delta > 0 && delta < 40);
            vassert((delta & 3) == 0);
            UInt notCond = 1 ^ (UInt)i->ARMin.XIndir.cond;
            vassert(notCond <= 13); /* Neither AL nor NV */
            delta = (delta >> 2) - 2;
            *ptmp = XX______(notCond, X1010) | (delta & 0xFFFFFF);
         }
         goto done;
      }

      case ARMin_XAssisted: {
         /* Use ptmp for backpatching conditional jumps. */
         UInt* ptmp = NULL;

         /* First off, if this is conditional, create a conditional
            jump over the rest of it.  Or at least, leave a space for
            it that we will shortly fill in. */
         if (i->ARMin.XAssisted.cond != ARMcc_AL) {
            vassert(i->ARMin.XAssisted.cond != ARMcc_NV);
            ptmp = p;
            *p++ = 0;
         }

         /* Update the guest R15T. */
         /* str r-dstGA, amR15T */
         p = do_load_or_store32(p, False/*!isLoad*/,
                                iregNo(i->ARMin.XAssisted.dstGA),
                                i->ARMin.XAssisted.amR15T);

         /* movw r8,  $magic_number */
         UInt trcval = 0;
         switch (i->ARMin.XAssisted.jk) {
            case Ijk_ClientReq:   trcval = VEX_TRC_JMP_CLIENTREQ;   break;
            case Ijk_Sys_syscall: trcval = VEX_TRC_JMP_SYS_SYSCALL; break;
            //case Ijk_Sys_int128:  trcval = VEX_TRC_JMP_SYS_INT128;  break;
            case Ijk_Yield:       trcval = VEX_TRC_JMP_YIELD;       break;
            //case Ijk_EmWarn:      trcval = VEX_TRC_JMP_EMWARN;      break;
            //case Ijk_MapFail:     trcval = VEX_TRC_JMP_MAPFAIL;     break;
            case Ijk_NoDecode:    trcval = VEX_TRC_JMP_NODECODE;    break;
            case Ijk_InvalICache: trcval = VEX_TRC_JMP_INVALICACHE; break;
            case Ijk_NoRedir:     trcval = VEX_TRC_JMP_NOREDIR;     break;
            //case Ijk_SigTRAP:     trcval = VEX_TRC_JMP_SIGTRAP;     break;
            //case Ijk_SigSEGV:     trcval = VEX_TRC_JMP_SIGSEGV;     break;
            case Ijk_Boring:      trcval = VEX_TRC_JMP_BORING;      break;
            /* We don't expect to see the following being assisted. */
            //case Ijk_Ret:
            //case Ijk_Call:
            /* fallthrough */
            default:
               ppIRJumpKind(i->ARMin.XAssisted.jk);
               vpanic("emit_ARMInstr.ARMin_XAssisted: unexpected jump kind");
         }
         vassert(trcval != 0);
         p = imm32_to_iregNo(p, /*r*/8, trcval);

         /* movw r12, lo16(VG_(disp_cp_xassisted)) */
         /* movt r12, hi16(VG_(disp_cp_xassisted)) */
         /* bx   r12  (A1) */
         p = imm32_to_iregNo(p, /*r*/12,
                             (UInt)Ptr_to_ULong(disp_cp_xassisted));
         *p++ = 0xE12FFF1C;

         /* Fix up the conditional jump, if there was one. */
         if (i->ARMin.XAssisted.cond != ARMcc_AL) {
            Int delta = (UChar*)p - (UChar*)ptmp; /* must be signed */
            vassert(delta > 0 && delta < 40);
            vassert((delta & 3) == 0);
            UInt notCond = 1 ^ (UInt)i->ARMin.XAssisted.cond;
            vassert(notCond <= 13); /* Neither AL nor NV */
            delta = (delta >> 2) - 2;
            *ptmp = XX______(notCond, X1010) | (delta & 0xFFFFFF);
         }
         goto done;
      }

      case ARMin_CMov: {
         UInt instr  = skeletal_RI84(i->ARMin.CMov.src);
         UInt subopc = X1101; /* MOV */
         UInt SBZ    = 0;
         instr |= XXXXX___(i->ARMin.CMov.cond, (1 & (subopc >> 3)),
                           (subopc << 1) & 0xF, SBZ,
                           iregNo(i->ARMin.CMov.dst));
         *p++ = instr;
         goto done;
      }

      case ARMin_Call: {
         UInt instr;
         /* Decide on a scratch reg used to hold to the call address.
            This has to be done as per the comments in getRegUsage. */
         Int scratchNo;
         switch (i->ARMin.Call.nArgRegs) {
            case 0:  scratchNo = 0;  break;
            case 1:  scratchNo = 1;  break;
            case 2:  scratchNo = 2;  break;
            case 3:  scratchNo = 3;  break;
            case 4:  scratchNo = 11; break;
            default: vassert(0);
         }
         /* If we don't need to do any fixup actions in the case that
            the call doesn't happen, just do the simple thing and emit
            straight-line code.  We hope this is the common case. */
         if (i->ARMin.Call.cond == ARMcc_AL/*call always happens*/
             || i->ARMin.Call.rloc.pri == RLPri_None/*no fixup action*/) {
            // r"scratchNo" = &target
            p = imm32_to_iregNo( (UInt*)p,
                                 scratchNo, (UInt)i->ARMin.Call.target );
            // blx{cond} r"scratchNo"
            instr = XXX___XX(i->ARMin.Call.cond, X0001, X0010, /*___*/
                             X0011, scratchNo);
            instr |= 0xFFF << 8; // stick in the SBOnes
            *p++ = instr;
         } else {
            Int delta;
            /* Complex case.  We have to generate an if-then-else
               diamond. */
            // before:
            //   b{!cond} else:
            //   r"scratchNo" = &target
            //   blx{AL} r"scratchNo"
            // preElse:
            //   b after:
            // else:
            //   mov r0, #0x55555555  // possibly
            //   mov r1, r0           // possibly
            // after:

            // before:
            UInt* pBefore = p;

            //   b{!cond} else:  // ptmp1 points here
            *p++ = 0; // filled in later

            //   r"scratchNo" = &target
            p = imm32_to_iregNo( (UInt*)p,
                                 scratchNo, (UInt)i->ARMin.Call.target );

            //   blx{AL} r"scratchNo"
            instr = XXX___XX(ARMcc_AL, X0001, X0010, /*___*/
                             X0011, scratchNo);
            instr |= 0xFFF << 8; // stick in the SBOnes
            *p++ = instr;

            // preElse:
            UInt* pPreElse = p;

            //   b after:
            *p++ = 0; // filled in later

            // else:
            delta = (UChar*)p - (UChar*)pBefore;
            delta = (delta >> 2) - 2;
            *pBefore
               = XX______(1 ^ i->ARMin.Call.cond, X1010) | (delta & 0xFFFFFF);

            /* Do the 'else' actions */
            switch (i->ARMin.Call.rloc.pri) {
               case RLPri_Int:
                  p = imm32_to_iregNo_EXACTLY2(p, /*r*/0, 0x55555555);
                  break;
               case RLPri_2Int:
                  vassert(0); //ATC
                  p = imm32_to_iregNo_EXACTLY2(p, /*r*/0, 0x55555555);
                  /* mov r1, r0 */
                  *p++ = 0xE1A01000;
                  break;
               case RLPri_None: case RLPri_INVALID: default:
                  vassert(0);
            }

            // after:
            delta = (UChar*)p - (UChar*)pPreElse;
            delta = (delta >> 2) - 2;
            *pPreElse = XX______(ARMcc_AL, X1010) | (delta & 0xFFFFFF);
         }

         goto done;
      }

      case ARMin_Mul: {
         /* E0000392   mul     r0, r2, r3
            E0810392   umull   r0(LO), r1(HI), r2, r3
            E0C10392   smull   r0(LO), r1(HI), r2, r3
         */
         switch (i->ARMin.Mul.op) {
            case ARMmul_PLAIN: *p++ = 0xE0000392; goto done;
            case ARMmul_ZX:    *p++ = 0xE0810392; goto done;
            case ARMmul_SX:    *p++ = 0xE0C10392; goto done;
            default: vassert(0);
         }
         goto bad;
      }
      case ARMin_LdrEX: {
         /* E1D42F9F   ldrexb r2, [r4]
            E1F42F9F   ldrexh r2, [r4]
            E1942F9F   ldrex  r2, [r4]
            E1B42F9F   ldrexd r2, r3, [r4]
         */
         switch (i->ARMin.LdrEX.szB) {
            case 1: *p++ = 0xE1D42F9F; goto done;
            case 2: *p++ = 0xE1F42F9F; goto done;
            case 4: *p++ = 0xE1942F9F; goto done;
            case 8: *p++ = 0xE1B42F9F; goto done;
            default: break;
         }
         goto bad;
      }
      case ARMin_StrEX: {
         /* E1C40F92   strexb r0, r2, [r4]
            E1E40F92   strexh r0, r2, [r4]
            E1840F92   strex  r0, r2, [r4]
            E1A40F92   strexd r0, r2, r3, [r4]
         */
         switch (i->ARMin.StrEX.szB) {
            case 1: *p++ = 0xE1C40F92; goto done;
            case 2: *p++ = 0xE1E40F92; goto done;
            case 4: *p++ = 0xE1840F92; goto done;
            case 8: *p++ = 0xE1A40F92; goto done;
            default: break;
         }
         goto bad;
      }
      case ARMin_VLdStD: {
         UInt dD     = dregNo(i->ARMin.VLdStD.dD);
         UInt rN     = iregNo(i->ARMin.VLdStD.amode->reg);
         Int  simm11 = i->ARMin.VLdStD.amode->simm11;
         UInt off8   = simm11 >= 0 ? simm11 : ((UInt)(-simm11));
         UInt bU     = simm11 >= 0 ? 1 : 0;
         UInt bL     = i->ARMin.VLdStD.isLoad ? 1 : 0;
         UInt insn;
         vassert(0 == (off8 & 3));
         off8 >>= 2;
         vassert(0 == (off8 & 0xFFFFFF00));
         insn = XXXXXX__(0xE,X1101,BITS4(bU,0,0,bL),rN,dD,X1011);
         insn |= off8;
         *p++ = insn;
         goto done;
      }
      case ARMin_VLdStS: {
         UInt fD     = fregNo(i->ARMin.VLdStS.fD);
         UInt rN     = iregNo(i->ARMin.VLdStS.amode->reg);
         Int  simm11 = i->ARMin.VLdStS.amode->simm11;
         UInt off8   = simm11 >= 0 ? simm11 : ((UInt)(-simm11));
         UInt bU     = simm11 >= 0 ? 1 : 0;
         UInt bL     = i->ARMin.VLdStS.isLoad ? 1 : 0;
         UInt bD     = fD & 1;
         UInt insn;
         vassert(0 == (off8 & 3));
         off8 >>= 2;
         vassert(0 == (off8 & 0xFFFFFF00));
         insn = XXXXXX__(0xE,X1101,BITS4(bU,bD,0,bL),rN, (fD >> 1), X1010);
         insn |= off8;
         *p++ = insn;
         goto done;
      }
      case ARMin_VAluD: {
         UInt dN = dregNo(i->ARMin.VAluD.argL);
         UInt dD = dregNo(i->ARMin.VAluD.dst);
         UInt dM = dregNo(i->ARMin.VAluD.argR);
         UInt pqrs = X1111; /* undefined */
         switch (i->ARMin.VAluD.op) {
            case ARMvfp_ADD: pqrs = X0110; break;
            case ARMvfp_SUB: pqrs = X0111; break;
            case ARMvfp_MUL: pqrs = X0100; break;
            case ARMvfp_DIV: pqrs = X1000; break;
            default: goto bad;
         }
         vassert(pqrs != X1111);
         UInt bP  = (pqrs >> 3) & 1;
         UInt bQ  = (pqrs >> 2) & 1;
         UInt bR  = (pqrs >> 1) & 1;
         UInt bS  = (pqrs >> 0) & 1;
         UInt insn = XXXXXXXX(0xE, X1110, BITS4(bP,0,bQ,bR), dN, dD,
                              X1011, BITS4(0,bS,0,0), dM);
         *p++ = insn;
         goto done;
      }
      case ARMin_VAluS: {
         UInt dN = fregNo(i->ARMin.VAluS.argL);
         UInt dD = fregNo(i->ARMin.VAluS.dst);
         UInt dM = fregNo(i->ARMin.VAluS.argR);
         UInt bN = dN & 1;
         UInt bD = dD & 1;
         UInt bM = dM & 1;
         UInt pqrs = X1111; /* undefined */
         switch (i->ARMin.VAluS.op) {
            case ARMvfp_ADD: pqrs = X0110; break;
            case ARMvfp_SUB: pqrs = X0111; break;
            case ARMvfp_MUL: pqrs = X0100; break;
            case ARMvfp_DIV: pqrs = X1000; break;
            default: goto bad;
         }
         vassert(pqrs != X1111);
         UInt bP  = (pqrs >> 3) & 1;
         UInt bQ  = (pqrs >> 2) & 1;
         UInt bR  = (pqrs >> 1) & 1;
         UInt bS  = (pqrs >> 0) & 1;
         UInt insn = XXXXXXXX(0xE, X1110, BITS4(bP,bD,bQ,bR),
                              (dN >> 1), (dD >> 1),
                              X1010, BITS4(bN,bS,bM,0), (dM >> 1));
         *p++ = insn;
         goto done;
      }
      case ARMin_VUnaryD: {
         UInt dD   = dregNo(i->ARMin.VUnaryD.dst);
         UInt dM   = dregNo(i->ARMin.VUnaryD.src);
         UInt insn = 0;
         switch (i->ARMin.VUnaryD.op) {
            case ARMvfpu_COPY:
               insn = XXXXXXXX(0xE, X1110,X1011,X0000,dD,X1011,X0100,dM);
               break;
            case ARMvfpu_ABS:
               insn = XXXXXXXX(0xE, X1110,X1011,X0000,dD,X1011,X1100,dM);
               break;
            case ARMvfpu_NEG:
               insn = XXXXXXXX(0xE, X1110,X1011,X0001,dD,X1011,X0100,dM);
               break;
            case ARMvfpu_SQRT:
               insn = XXXXXXXX(0xE, X1110,X1011,X0001,dD,X1011,X1100,dM);
               break;
            default:
               goto bad;
         }
         *p++ = insn;
         goto done;
      }
      case ARMin_VUnaryS: {
         UInt fD   = fregNo(i->ARMin.VUnaryS.dst);
         UInt fM   = fregNo(i->ARMin.VUnaryS.src);
         UInt insn = 0;
         switch (i->ARMin.VUnaryS.op) {
            case ARMvfpu_COPY:
               insn = XXXXXXXX(0xE, X1110, BITS4(1,(fD & 1),1,1), X0000,
                               (fD >> 1), X1010, BITS4(0,1,(fM & 1),0),
                               (fM >> 1));
               break;
            case ARMvfpu_ABS:
               insn = XXXXXXXX(0xE, X1110, BITS4(1,(fD & 1),1,1), X0000,
                               (fD >> 1), X1010, BITS4(1,1,(fM & 1),0),
                               (fM >> 1));
               break;
            case ARMvfpu_NEG:
               insn = XXXXXXXX(0xE, X1110, BITS4(1,(fD & 1),1,1), X0001,
                               (fD >> 1), X1010, BITS4(0,1,(fM & 1),0),
                               (fM >> 1));
               break;
            case ARMvfpu_SQRT:
               insn = XXXXXXXX(0xE, X1110, BITS4(1,(fD & 1),1,1), X0001,
                               (fD >> 1), X1010, BITS4(1,1,(fM & 1),0),
                               (fM >> 1));
               break;
            default:
               goto bad;
         }
         *p++ = insn;
         goto done;
      }
      case ARMin_VCmpD: {
         UInt dD   = dregNo(i->ARMin.VCmpD.argL);
         UInt dM   = dregNo(i->ARMin.VCmpD.argR);
         UInt insn = XXXXXXXX(0xE, X1110, X1011, X0100, dD, X1011, X0100, dM);
         *p++ = insn;       /* FCMPD dD, dM */
         *p++ = 0xEEF1FA10; /* FMSTAT */
         goto done;
      }
      case ARMin_VCMovD: {
         UInt cc = (UInt)i->ARMin.VCMovD.cond;
         UInt dD = dregNo(i->ARMin.VCMovD.dst);
         UInt dM = dregNo(i->ARMin.VCMovD.src);
         vassert(cc < 16 && cc != ARMcc_AL);
         UInt insn = XXXXXXXX(cc, X1110,X1011,X0000,dD,X1011,X0100,dM);
         *p++ = insn;
         goto done;
      }
      case ARMin_VCMovS: {
         UInt cc = (UInt)i->ARMin.VCMovS.cond;
         UInt fD = fregNo(i->ARMin.VCMovS.dst);
         UInt fM = fregNo(i->ARMin.VCMovS.src);
         vassert(cc < 16 && cc != ARMcc_AL);
         UInt insn = XXXXXXXX(cc, X1110, BITS4(1,(fD & 1),1,1),
                              X0000,(fD >> 1),X1010,
                              BITS4(0,1,(fM & 1),0), (fM >> 1));
         *p++ = insn;
         goto done;
      }
      case ARMin_VCvtSD: {
         if (i->ARMin.VCvtSD.sToD) {
            UInt dD = dregNo(i->ARMin.VCvtSD.dst);
            UInt fM = fregNo(i->ARMin.VCvtSD.src);
            UInt insn = XXXXXXXX(0xE, X1110, X1011, X0111, dD, X1010,
                                 BITS4(1,1, (fM & 1), 0),
                                 (fM >> 1));
            *p++ = insn;
            goto done;
         } else {
            UInt fD = fregNo(i->ARMin.VCvtSD.dst);
            UInt dM = dregNo(i->ARMin.VCvtSD.src);
            UInt insn = XXXXXXXX(0xE, X1110, BITS4(1,(fD & 1),1,1),
                                 X0111, (fD >> 1),
                                 X1011, X1100, dM);
            *p++ = insn;
            goto done;
         }
      }
      case ARMin_VXferD: {
         UInt dD  = dregNo(i->ARMin.VXferD.dD);
         UInt rHi = iregNo(i->ARMin.VXferD.rHi);
         UInt rLo = iregNo(i->ARMin.VXferD.rLo);
         /* vmov dD, rLo, rHi is
            E C 4 rHi rLo B (0,0,dD[4],1) dD[3:0]
            vmov rLo, rHi, dD is
            E C 5 rHi rLo B (0,0,dD[4],1) dD[3:0]
         */
         UInt insn
            = XXXXXXXX(0xE, 0xC, i->ARMin.VXferD.toD ? 4 : 5,
                       rHi, rLo, 0xB,
                       BITS4(0,0, ((dD >> 4) & 1), 1), (dD & 0xF));
         *p++ = insn;
         goto done;
      }
      case ARMin_VXferS: {
         UInt fD  = fregNo(i->ARMin.VXferS.fD);
         UInt rLo = iregNo(i->ARMin.VXferS.rLo);
         /* vmov fD, rLo is
            E E 0 fD[4:1] rLo A (fD[0],0,0,1) 0
            vmov rLo, fD is
            E E 1 fD[4:1] rLo A (fD[0],0,0,1) 0
         */
         UInt insn
            = XXXXXXXX(0xE, 0xE, i->ARMin.VXferS.toS ? 0 : 1,
                       (fD >> 1) & 0xF, rLo, 0xA,
                       BITS4((fD & 1),0,0,1), 0);
         *p++ = insn;
         goto done;
      }
      case ARMin_VCvtID: {
         Bool iToD = i->ARMin.VCvtID.iToD;
         Bool syned = i->ARMin.VCvtID.syned;
         if (iToD && syned) {
            // FSITOD: I32S-in-freg to F64-in-dreg
            UInt regF = fregNo(i->ARMin.VCvtID.src);
            UInt regD = dregNo(i->ARMin.VCvtID.dst);
            UInt insn = XXXXXXXX(0xE, X1110, X1011, X1000, regD,
                                 X1011, BITS4(1,1,(regF & 1),0),
                                 (regF >> 1) & 0xF);
            *p++ = insn;
            goto done;
         }
         if (iToD && (!syned)) {
            // FUITOD: I32U-in-freg to F64-in-dreg
            UInt regF = fregNo(i->ARMin.VCvtID.src);
            UInt regD = dregNo(i->ARMin.VCvtID.dst);
            UInt insn = XXXXXXXX(0xE, X1110, X1011, X1000, regD,
                                 X1011, BITS4(0,1,(regF & 1),0),
                                 (regF >> 1) & 0xF);
            *p++ = insn;
            goto done;
         }
         if ((!iToD) && syned) {
            // FTOSID: F64-in-dreg to I32S-in-freg
            UInt regD = dregNo(i->ARMin.VCvtID.src);
            UInt regF = fregNo(i->ARMin.VCvtID.dst);
            UInt insn = XXXXXXXX(0xE, X1110, BITS4(1,(regF & 1),1,1),
                                 X1101, (regF >> 1) & 0xF,
                                 X1011, X0100, regD);
            *p++ = insn;
            goto done;
         }
         if ((!iToD) && (!syned)) {
            // FTOUID: F64-in-dreg to I32U-in-freg
            UInt regD = dregNo(i->ARMin.VCvtID.src);
            UInt regF = fregNo(i->ARMin.VCvtID.dst);
            UInt insn = XXXXXXXX(0xE, X1110, BITS4(1,(regF & 1),1,1),
                                 X1100, (regF >> 1) & 0xF,
                                 X1011, X0100, regD);
            *p++ = insn;
            goto done;
         }
         /*UNREACHED*/
         vassert(0);
      }
      case ARMin_FPSCR: {
         Bool toFPSCR = i->ARMin.FPSCR.toFPSCR;
         UInt iReg    = iregNo(i->ARMin.FPSCR.iReg);
         if (toFPSCR) {
            /* fmxr fpscr, iReg is EEE1 iReg A10 */
            *p++ = 0xEEE10A10 | ((iReg & 0xF) << 12);
            goto done;
         }
         goto bad; // FPSCR -> iReg case currently ATC
      }
      case ARMin_MFence: {
         // It's not clear (to me) how these relate to the ARMv7
         // versions, so let's just use the v7 versions as they
         // are at least well documented.
         //*p++ = 0xEE070F9A; /* mcr 15,0,r0,c7,c10,4 (DSB) */
         //*p++ = 0xEE070FBA; /* mcr 15,0,r0,c7,c10,5 (DMB) */
         //*p++ = 0xEE070F95; /* mcr 15,0,r0,c7,c5,4  (ISB) */
         *p++ = 0xF57FF04F; /* DSB sy */
         *p++ = 0xF57FF05F; /* DMB sy */
         *p++ = 0xF57FF06F; /* ISB */
         goto done;
      }
      case ARMin_CLREX: {
         *p++ = 0xF57FF01F; /* clrex */
         goto done;
      }

      case ARMin_NLdStQ: {
         UInt regD = qregNo(i->ARMin.NLdStQ.dQ) << 1;
         UInt regN, regM;
         UInt D = regD >> 4;
         UInt bL = i->ARMin.NLdStQ.isLoad ? 1 : 0;
         UInt insn;
         vassert(hregClass(i->ARMin.NLdStQ.dQ) == HRcVec128);
         regD &= 0xF;
         if (i->ARMin.NLdStQ.amode->tag == ARMamN_RR) {
            regN = iregNo(i->ARMin.NLdStQ.amode->ARMamN.RR.rN);
            regM = iregNo(i->ARMin.NLdStQ.amode->ARMamN.RR.rM);
         } else {
            regN = iregNo(i->ARMin.NLdStQ.amode->ARMamN.R.rN);
            regM = 15;
         }
         insn = XXXXXXXX(0xF, X0100, BITS4(0, D, bL, 0),
                              regN, regD, X1010, X1000, regM);
         *p++ = insn;
         goto done;
      }
      case ARMin_NLdStD: {
         UInt regD = dregNo(i->ARMin.NLdStD.dD);
         UInt regN, regM;
         UInt D = regD >> 4;
         UInt bL = i->ARMin.NLdStD.isLoad ? 1 : 0;
         UInt insn;
         vassert(hregClass(i->ARMin.NLdStD.dD) == HRcFlt64);
         regD &= 0xF;
         if (i->ARMin.NLdStD.amode->tag == ARMamN_RR) {
            regN = iregNo(i->ARMin.NLdStD.amode->ARMamN.RR.rN);
            regM = iregNo(i->ARMin.NLdStD.amode->ARMamN.RR.rM);
         } else {
            regN = iregNo(i->ARMin.NLdStD.amode->ARMamN.R.rN);
            regM = 15;
         }
         insn = XXXXXXXX(0xF, X0100, BITS4(0, D, bL, 0),
                              regN, regD, X0111, X1000, regM);
         *p++ = insn;
         goto done;
      }
      case ARMin_NUnaryS: {
         UInt Q = i->ARMin.NUnaryS.Q ? 1 : 0;
         UInt regD, D;
         UInt regM, M;
         UInt size = i->ARMin.NUnaryS.size;
         UInt insn;
         UInt opc, opc1, opc2;
         switch (i->ARMin.NUnaryS.op) {
	    case ARMneon_VDUP:
               if (i->ARMin.NUnaryS.size >= 16)
                  goto bad;
               if (i->ARMin.NUnaryS.dst->tag != ARMNRS_Reg)
                  goto bad;
               if (i->ARMin.NUnaryS.src->tag != ARMNRS_Scalar)
                  goto bad;
               regD = (hregClass(i->ARMin.NUnaryS.dst->reg) == HRcVec128)
                        ? (qregNo(i->ARMin.NUnaryS.dst->reg) << 1)
                        : dregNo(i->ARMin.NUnaryS.dst->reg);
               regM = (hregClass(i->ARMin.NUnaryS.src->reg) == HRcVec128)
                        ? (qregNo(i->ARMin.NUnaryS.src->reg) << 1)
                        : dregNo(i->ARMin.NUnaryS.src->reg);
               D = regD >> 4;
               M = regM >> 4;
               regD &= 0xf;
               regM &= 0xf;
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1),
                               (i->ARMin.NUnaryS.size & 0xf), regD,
                               X1100, BITS4(0,Q,M,0), regM);
               *p++ = insn;
               goto done;
            case ARMneon_SETELEM:
               regD = Q ? (qregNo(i->ARMin.NUnaryS.dst->reg) << 1) :
                                dregNo(i->ARMin.NUnaryS.dst->reg);
               regM = iregNo(i->ARMin.NUnaryS.src->reg);
               M = regM >> 4;
               D = regD >> 4;
               regM &= 0xF;
               regD &= 0xF;
               if (i->ARMin.NUnaryS.dst->tag != ARMNRS_Scalar)
                  goto bad;
               switch (size) {
                  case 0:
                     if (i->ARMin.NUnaryS.dst->index > 7)
                        goto bad;
                     opc = X1000 | i->ARMin.NUnaryS.dst->index;
                     break;
                  case 1:
                     if (i->ARMin.NUnaryS.dst->index > 3)
                        goto bad;
                     opc = X0001 | (i->ARMin.NUnaryS.dst->index << 1);
                     break;
                  case 2:
                     if (i->ARMin.NUnaryS.dst->index > 1)
                        goto bad;
                     opc = X0000 | (i->ARMin.NUnaryS.dst->index << 2);
                     break;
                  default:
                     goto bad;
               }
               opc1 = (opc >> 2) & 3;
               opc2 = opc & 3;
               insn = XXXXXXXX(0xE, X1110, BITS4(0,(opc1 >> 1),(opc1 & 1),0),
                               regD, regM, X1011,
                               BITS4(D,(opc2 >> 1),(opc2 & 1),1), X0000);
               *p++ = insn;
               goto done;
            case ARMneon_GETELEMU:
               regM = Q ? (qregNo(i->ARMin.NUnaryS.src->reg) << 1) :
                                dregNo(i->ARMin.NUnaryS.src->reg);
               regD = iregNo(i->ARMin.NUnaryS.dst->reg);
               M = regM >> 4;
               D = regD >> 4;
               regM &= 0xF;
               regD &= 0xF;
               if (i->ARMin.NUnaryS.src->tag != ARMNRS_Scalar)
                  goto bad;
               switch (size) {
                  case 0:
                     if (Q && i->ARMin.NUnaryS.src->index > 7) {
                        regM++;
                        i->ARMin.NUnaryS.src->index -= 8;
                     }
                     if (i->ARMin.NUnaryS.src->index > 7)
                        goto bad;
                     opc = X1000 | i->ARMin.NUnaryS.src->index;
                     break;
                  case 1:
                     if (Q && i->ARMin.NUnaryS.src->index > 3) {
                        regM++;
                        i->ARMin.NUnaryS.src->index -= 4;
                     }
                     if (i->ARMin.NUnaryS.src->index > 3)
                        goto bad;
                     opc = X0001 | (i->ARMin.NUnaryS.src->index << 1);
                     break;
                  case 2:
                     goto bad;
                  default:
                     goto bad;
               }
               opc1 = (opc >> 2) & 3;
               opc2 = opc & 3;
               insn = XXXXXXXX(0xE, X1110, BITS4(1,(opc1 >> 1),(opc1 & 1),1),
                               regM, regD, X1011,
                               BITS4(M,(opc2 >> 1),(opc2 & 1),1), X0000);
               *p++ = insn;
               goto done;
            case ARMneon_GETELEMS:
               regM = Q ? (qregNo(i->ARMin.NUnaryS.src->reg) << 1) :
                                dregNo(i->ARMin.NUnaryS.src->reg);
               regD = iregNo(i->ARMin.NUnaryS.dst->reg);
               M = regM >> 4;
               D = regD >> 4;
               regM &= 0xF;
               regD &= 0xF;
               if (i->ARMin.NUnaryS.src->tag != ARMNRS_Scalar)
                  goto bad;
               switch (size) {
                  case 0:
                     if (Q && i->ARMin.NUnaryS.src->index > 7) {
                        regM++;
                        i->ARMin.NUnaryS.src->index -= 8;
                     }
                     if (i->ARMin.NUnaryS.src->index > 7)
                        goto bad;
                     opc = X1000 | i->ARMin.NUnaryS.src->index;
                     break;
                  case 1:
                     if (Q && i->ARMin.NUnaryS.src->index > 3) {
                        regM++;
                        i->ARMin.NUnaryS.src->index -= 4;
                     }
                     if (i->ARMin.NUnaryS.src->index > 3)
                        goto bad;
                     opc = X0001 | (i->ARMin.NUnaryS.src->index << 1);
                     break;
                  case 2:
                     if (Q && i->ARMin.NUnaryS.src->index > 1) {
                        regM++;
                        i->ARMin.NUnaryS.src->index -= 2;
                     }
                     if (i->ARMin.NUnaryS.src->index > 1)
                        goto bad;
                     opc = X0000 | (i->ARMin.NUnaryS.src->index << 2);
                     break;
                  default:
                     goto bad;
               }
               opc1 = (opc >> 2) & 3;
               opc2 = opc & 3;
               insn = XXXXXXXX(0xE, X1110, BITS4(0,(opc1 >> 1),(opc1 & 1),1),
                               regM, regD, X1011,
                               BITS4(M,(opc2 >> 1),(opc2 & 1),1), X0000);
               *p++ = insn;
               goto done;
            default:
               goto bad;
         }
      }
      case ARMin_NUnary: {
         UInt Q = i->ARMin.NUnary.Q ? 1 : 0;
         UInt regD = (hregClass(i->ARMin.NUnary.dst) == HRcVec128)
                       ? (qregNo(i->ARMin.NUnary.dst) << 1)
                       : dregNo(i->ARMin.NUnary.dst);
         UInt regM, M;
         UInt D = regD >> 4;
         UInt sz1 = i->ARMin.NUnary.size >> 1;
         UInt sz2 = i->ARMin.NUnary.size & 1;
         UInt sz = i->ARMin.NUnary.size;
         UInt insn;
         UInt F = 0; /* TODO: floating point EQZ ??? */
         if (i->ARMin.NUnary.op != ARMneon_DUP) {
            regM = (hregClass(i->ARMin.NUnary.src) == HRcVec128)
                     ? (qregNo(i->ARMin.NUnary.src) << 1)
                     : dregNo(i->ARMin.NUnary.src);
            M = regM >> 4;
         } else {
            regM = iregNo(i->ARMin.NUnary.src);
            M = regM >> 4;
         }
         regD &= 0xF;
         regM &= 0xF;
         switch (i->ARMin.NUnary.op) {
            case ARMneon_COPY: /* VMOV reg, reg */
               insn = XXXXXXXX(0xF, X0010, BITS4(0,D,1,0), regM, regD, X0001,
                               BITS4(M,Q,M,1), regM);
               break;
            case ARMneon_COPYN: /* VMOVN regD, regQ */
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), BITS4(sz1,sz2,1,0),
                               regD, X0010, BITS4(0,0,M,0), regM);
               break;
            case ARMneon_COPYQNSS: /* VQMOVN regD, regQ */
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), BITS4(sz1,sz2,1,0),
                               regD, X0010, BITS4(1,0,M,0), regM);
               break;
            case ARMneon_COPYQNUS: /* VQMOVUN regD, regQ */
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), BITS4(sz1,sz2,1,0),
                               regD, X0010, BITS4(0,1,M,0), regM);
               break;
            case ARMneon_COPYQNUU: /* VQMOVN regD, regQ */
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), BITS4(sz1,sz2,1,0),
                               regD, X0010, BITS4(1,1,M,0), regM);
               break;
            case ARMneon_COPYLS: /* VMOVL regQ, regD */
               if (sz >= 3)
                  goto bad;
               insn = XXXXXXXX(0xF, X0010,
                               BITS4(1,D,(sz == 2) ? 1 : 0,(sz == 1) ? 1 : 0),
                               BITS4((sz == 0) ? 1 : 0,0,0,0),
                               regD, X1010, BITS4(0,0,M,1), regM);
               break;
            case ARMneon_COPYLU: /* VMOVL regQ, regD */
               if (sz >= 3)
                  goto bad;
               insn = XXXXXXXX(0xF, X0011,
                               BITS4(1,D,(sz == 2) ? 1 : 0,(sz == 1) ? 1 : 0),
                               BITS4((sz == 0) ? 1 : 0,0,0,0),
                               regD, X1010, BITS4(0,0,M,1), regM);
               break;
            case ARMneon_NOT: /* VMVN reg, reg*/
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), X0000, regD, X0101,
                               BITS4(1,Q,M,0), regM);
               break;
            case ARMneon_EQZ:
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), BITS4(sz1,sz2,0,1),
                               regD, BITS4(0,F,0,1), BITS4(0,Q,M,0), regM);
               break;
            case ARMneon_CNT:
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), X0000, regD, X0101,
                               BITS4(0,Q,M,0), regM);
               break;
            case ARMneon_CLZ:
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), BITS4(sz1,sz2,0,0),
                               regD, X0100, BITS4(1,Q,M,0), regM);
               break;
            case ARMneon_CLS:
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), BITS4(sz1,sz2,0,0),
                               regD, X0100, BITS4(0,Q,M,0), regM);
               break;
            case ARMneon_ABS:
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), BITS4(sz1,sz2,0,1),
                               regD, X0011, BITS4(0,Q,M,0), regM);
               break;
            case ARMneon_DUP:
               sz1 = i->ARMin.NUnary.size == 0 ? 1 : 0;
               sz2 = i->ARMin.NUnary.size == 1 ? 1 : 0;
               vassert(sz1 + sz2 < 2);
               insn = XXXXXXXX(0xE, X1110, BITS4(1, sz1, Q, 0), regD, regM,
                               X1011, BITS4(D,0,sz2,1), X0000);
               break;
            case ARMneon_REV16:
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), BITS4(sz1,sz2,0,0),
                               regD, BITS4(0,0,0,1), BITS4(0,Q,M,0), regM);
               break;
            case ARMneon_REV32:
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), BITS4(sz1,sz2,0,0),
                               regD, BITS4(0,0,0,0), BITS4(1,Q,M,0), regM);
               break;
            case ARMneon_REV64:
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), BITS4(sz1,sz2,0,0),
                               regD, BITS4(0,0,0,0), BITS4(0,Q,M,0), regM);
               break;
            case ARMneon_PADDLU:
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), BITS4(sz1,sz2,0,0),
                               regD, X0010, BITS4(1,Q,M,0), regM);
               break;
            case ARMneon_PADDLS:
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), BITS4(sz1,sz2,0,0),
                               regD, X0010, BITS4(0,Q,M,0), regM);
               break;
            case ARMneon_VQSHLNUU:
               insn = XXXXXXXX(0xF, X0011,
                               (1 << 3) | (D << 2) | ((sz >> 4) & 3),
                               sz & 0xf, regD, X0111,
                               BITS4(sz >> 6,Q,M,1), regM);
               break;
            case ARMneon_VQSHLNSS:
               insn = XXXXXXXX(0xF, X0010,
                               (1 << 3) | (D << 2) | ((sz >> 4) & 3),
                               sz & 0xf, regD, X0111,
                               BITS4(sz >> 6,Q,M,1), regM);
               break;
            case ARMneon_VQSHLNUS:
               insn = XXXXXXXX(0xF, X0011,
                               (1 << 3) | (D << 2) | ((sz >> 4) & 3),
                               sz & 0xf, regD, X0110,
                               BITS4(sz >> 6,Q,M,1), regM);
               break;
            case ARMneon_VCVTFtoS:
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), X1011, regD, X0111,
                               BITS4(0,Q,M,0), regM);
               break;
            case ARMneon_VCVTFtoU:
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), X1011, regD, X0111,
                               BITS4(1,Q,M,0), regM);
               break;
            case ARMneon_VCVTStoF:
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), X1011, regD, X0110,
                               BITS4(0,Q,M,0), regM);
               break;
            case ARMneon_VCVTUtoF:
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), X1011, regD, X0110,
                               BITS4(1,Q,M,0), regM);
               break;
            case ARMneon_VCVTFtoFixedU:
               sz1 = (sz >> 5) & 1;
               sz2 = (sz >> 4) & 1;
               sz &= 0xf;
               insn = XXXXXXXX(0xF, X0011,
                               BITS4(1,D,sz1,sz2), sz, regD, X1111,
                               BITS4(0,Q,M,1), regM);
               break;
            case ARMneon_VCVTFtoFixedS:
               sz1 = (sz >> 5) & 1;
               sz2 = (sz >> 4) & 1;
               sz &= 0xf;
               insn = XXXXXXXX(0xF, X0010,
                               BITS4(1,D,sz1,sz2), sz, regD, X1111,
                               BITS4(0,Q,M,1), regM);
               break;
            case ARMneon_VCVTFixedUtoF:
               sz1 = (sz >> 5) & 1;
               sz2 = (sz >> 4) & 1;
               sz &= 0xf;
               insn = XXXXXXXX(0xF, X0011,
                               BITS4(1,D,sz1,sz2), sz, regD, X1110,
                               BITS4(0,Q,M,1), regM);
               break;
            case ARMneon_VCVTFixedStoF:
               sz1 = (sz >> 5) & 1;
               sz2 = (sz >> 4) & 1;
               sz &= 0xf;
               insn = XXXXXXXX(0xF, X0010,
                               BITS4(1,D,sz1,sz2), sz, regD, X1110,
                               BITS4(0,Q,M,1), regM);
               break;
            case ARMneon_VCVTF32toF16:
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), X0110, regD, X0110,
                               BITS4(0,0,M,0), regM);
               break;
            case ARMneon_VCVTF16toF32:
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), X0110, regD, X0111,
                               BITS4(0,0,M,0), regM);
               break;
            case ARMneon_VRECIP:
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), X1011, regD, X0100,
                               BITS4(0,Q,M,0), regM);
               break;
            case ARMneon_VRECIPF:
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), X1011, regD, X0101,
                               BITS4(0,Q,M,0), regM);
               break;
            case ARMneon_VABSFP:
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), X1001, regD, X0111,
                               BITS4(0,Q,M,0), regM);
               break;
            case ARMneon_VRSQRTEFP:
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), X1011, regD, X0101,
                               BITS4(1,Q,M,0), regM);
               break;
            case ARMneon_VRSQRTE:
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), X1011, regD, X0100,
                               BITS4(1,Q,M,0), regM);
               break;
            case ARMneon_VNEGF:
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), X1001, regD, X0111,
                               BITS4(1,Q,M,0), regM);
               break;

            default:
               goto bad;
         }
         *p++ = insn;
         goto done;
      }
      case ARMin_NDual: {
         UInt Q = i->ARMin.NDual.Q ? 1 : 0;
         UInt regD = (hregClass(i->ARMin.NDual.arg1) == HRcVec128)
                       ? (qregNo(i->ARMin.NDual.arg1) << 1)
                       : dregNo(i->ARMin.NDual.arg1);
         UInt regM = (hregClass(i->ARMin.NDual.arg2) == HRcVec128)
                       ? (qregNo(i->ARMin.NDual.arg2) << 1)
                       : dregNo(i->ARMin.NDual.arg2);
         UInt D = regD >> 4;
         UInt M = regM >> 4;
         UInt sz1 = i->ARMin.NDual.size >> 1;
         UInt sz2 = i->ARMin.NDual.size & 1;
         UInt insn;
         regD &= 0xF;
         regM &= 0xF;
         switch (i->ARMin.NDual.op) {
            case ARMneon_TRN: /* VTRN reg, reg */
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), BITS4(sz1,sz2,1,0),
                               regD, X0000, BITS4(1,Q,M,0), regM);
               break;
            case ARMneon_ZIP: /* VZIP reg, reg */
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), BITS4(sz1,sz2,1,0),
                               regD, X0001, BITS4(1,Q,M,0), regM);
               break;
            case ARMneon_UZP: /* VUZP reg, reg */
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), BITS4(sz1,sz2,1,0),
                               regD, X0001, BITS4(0,Q,M,0), regM);
               break;
            default:
               goto bad;
         }
         *p++ = insn;
         goto done;
      }
      case ARMin_NBinary: {
         UInt Q = i->ARMin.NBinary.Q ? 1 : 0;
         UInt regD = (hregClass(i->ARMin.NBinary.dst) == HRcVec128)
                       ? (qregNo(i->ARMin.NBinary.dst) << 1)
                       : dregNo(i->ARMin.NBinary.dst);
         UInt regN = (hregClass(i->ARMin.NBinary.argL) == HRcVec128)
                       ? (qregNo(i->ARMin.NBinary.argL) << 1)
                       : dregNo(i->ARMin.NBinary.argL);
         UInt regM = (hregClass(i->ARMin.NBinary.argR) == HRcVec128)
                       ? (qregNo(i->ARMin.NBinary.argR) << 1)
                       : dregNo(i->ARMin.NBinary.argR);
         UInt sz1 = i->ARMin.NBinary.size >> 1;
         UInt sz2 = i->ARMin.NBinary.size & 1;
         UInt D = regD >> 4;
         UInt N = regN >> 4;
         UInt M = regM >> 4;
         UInt insn;
         regD &= 0xF;
         regM &= 0xF;
         regN &= 0xF;
         switch (i->ARMin.NBinary.op) {
            case ARMneon_VAND: /* VAND reg, reg, reg */
               insn = XXXXXXXX(0xF, X0010, BITS4(0,D,0,0), regN, regD, X0001,
                               BITS4(N,Q,M,1), regM);
               break;
            case ARMneon_VORR: /* VORR reg, reg, reg*/
               insn = XXXXXXXX(0xF, X0010, BITS4(0,D,1,0), regN, regD, X0001,
                               BITS4(N,Q,M,1), regM);
               break;
            case ARMneon_VXOR: /* VEOR reg, reg, reg */
               insn = XXXXXXXX(0xF, X0011, BITS4(0,D,0,0), regN, regD, X0001,
                               BITS4(N,Q,M,1), regM);
               break;
            case ARMneon_VADD: /* VADD reg, reg, reg */
               insn = XXXXXXXX(0xF, X0010, BITS4(0,D,sz1,sz2), regN, regD,
                               X1000, BITS4(N,Q,M,0), regM);
               break;
            case ARMneon_VSUB: /* VSUB reg, reg, reg */
               insn = XXXXXXXX(0xF, X0011, BITS4(0,D,sz1,sz2), regN, regD,
                               X1000, BITS4(N,Q,M,0), regM);
               break;
            case ARMneon_VMINU: /* VMIN.Uxx reg, reg, reg */
               insn = XXXXXXXX(0xF, X0011, BITS4(0,D,sz1,sz2), regN, regD,
                               X0110, BITS4(N,Q,M,1), regM);
               break;
            case ARMneon_VMINS: /* VMIN.Sxx reg, reg, reg */
               insn = XXXXXXXX(0xF, X0010, BITS4(0,D,sz1,sz2), regN, regD,
                               X0110, BITS4(N,Q,M,1), regM);
               break;
            case ARMneon_VMAXU: /* VMAX.Uxx reg, reg, reg */
               insn = XXXXXXXX(0xF, X0011, BITS4(0,D,sz1,sz2), regN, regD,
                               X0110, BITS4(N,Q,M,0), regM);
               break;
            case ARMneon_VMAXS: /* VMAX.Sxx reg, reg, reg */
               insn = XXXXXXXX(0xF, X0010, BITS4(0,D,sz1,sz2), regN, regD,
                               X0110, BITS4(N,Q,M,0), regM);
               break;
            case ARMneon_VRHADDS: /* VRHADD.Sxx reg, reg, reg */
               insn = XXXXXXXX(0xF, X0010, BITS4(0,D,sz1,sz2), regN, regD,
                               X0001, BITS4(N,Q,M,0), regM);
               break;
            case ARMneon_VRHADDU: /* VRHADD.Uxx reg, reg, reg */
               insn = XXXXXXXX(0xF, X0011, BITS4(0,D,sz1,sz2), regN, regD,
                               X0001, BITS4(N,Q,M,0), regM);
               break;
            case ARMneon_VQADDU: /* VQADD unsigned reg, reg, reg */
               insn = XXXXXXXX(0xF, X0011, BITS4(0,D,sz1,sz2), regN, regD,
                               X0000, BITS4(N,Q,M,1), regM);
               break;
            case ARMneon_VQADDS: /* VQADD signed reg, reg, reg */
               insn = XXXXXXXX(0xF, X0010, BITS4(0,D,sz1,sz2), regN, regD,
                               X0000, BITS4(N,Q,M,1), regM);
               break;
            case ARMneon_VQSUBU: /* VQSUB unsigned reg, reg, reg */
               insn = XXXXXXXX(0xF, X0011, BITS4(0,D,sz1,sz2), regN, regD,
                               X0010, BITS4(N,Q,M,1), regM);
               break;
            case ARMneon_VQSUBS: /* VQSUB signed reg, reg, reg */
               insn = XXXXXXXX(0xF, X0010, BITS4(0,D,sz1,sz2), regN, regD,
                               X0010, BITS4(N,Q,M,1), regM);
               break;
            case ARMneon_VCGTU: /* VCGT unsigned reg, reg, reg */
               insn = XXXXXXXX(0xF, X0011, BITS4(0,D,sz1,sz2), regN, regD,
                               X0011, BITS4(N,Q,M,0), regM);
               break;
            case ARMneon_VCGTS: /* VCGT signed reg, reg, reg */
               insn = XXXXXXXX(0xF, X0010, BITS4(0,D,sz1,sz2), regN, regD,
                               X0011, BITS4(N,Q,M,0), regM);
               break;
            case ARMneon_VCGEU: /* VCGE unsigned reg, reg, reg */
               insn = XXXXXXXX(0xF, X0011, BITS4(0,D,sz1,sz2), regN, regD,
                               X0011, BITS4(N,Q,M,1), regM);
               break;
            case ARMneon_VCGES: /* VCGE signed reg, reg, reg */
               insn = XXXXXXXX(0xF, X0010, BITS4(0,D,sz1,sz2), regN, regD,
                               X0011, BITS4(N,Q,M,1), regM);
               break;
            case ARMneon_VCEQ: /* VCEQ reg, reg, reg */
               insn = XXXXXXXX(0xF, X0011, BITS4(0,D,sz1,sz2), regN, regD,
                               X1000, BITS4(N,Q,M,1), regM);
               break;
            case ARMneon_VEXT: /* VEXT.8 reg, reg, #imm4*/
               if (i->ARMin.NBinary.size >= 16)
                  goto bad;
               insn = XXXXXXXX(0xF, X0010, BITS4(1,D,1,1), regN, regD,
                               i->ARMin.NBinary.size & 0xf, BITS4(N,Q,M,0),
                               regM);
               break;
            case ARMneon_VMUL:
               insn = XXXXXXXX(0xF, X0010, BITS4(0,D,sz1,sz2), regN, regD,
                               X1001, BITS4(N,Q,M,1), regM);
               break;
            case ARMneon_VMULLU:
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,sz1,sz2), regN, regD,
                               X1100, BITS4(N,0,M,0), regM);
               break;
            case ARMneon_VMULLS:
               insn = XXXXXXXX(0xF, X0010, BITS4(1,D,sz1,sz2), regN, regD,
                               X1100, BITS4(N,0,M,0), regM);
               break;
            case ARMneon_VMULP:
               insn = XXXXXXXX(0xF, X0011, BITS4(0,D,sz1,sz2), regN, regD,
                               X1001, BITS4(N,Q,M,1), regM);
               break;
            case ARMneon_VMULFP:
               insn = XXXXXXXX(0xF, X0011, BITS4(0,D,0,0), regN, regD,
                               X1101, BITS4(N,Q,M,1), regM);
               break;
            case ARMneon_VMULLP:
               insn = XXXXXXXX(0xF, X0010, BITS4(1,D,sz1,sz2), regN, regD,
                               X1110, BITS4(N,0,M,0), regM);
               break;
            case ARMneon_VQDMULH:
               insn = XXXXXXXX(0xF, X0010, BITS4(0,D,sz1,sz2), regN, regD,
                               X1011, BITS4(N,Q,M,0), regM);
               break;
            case ARMneon_VQRDMULH:
               insn = XXXXXXXX(0xF, X0011, BITS4(0,D,sz1,sz2), regN, regD,
                               X1011, BITS4(N,Q,M,0), regM);
               break;
            case ARMneon_VQDMULL:
               insn = XXXXXXXX(0xF, X0010, BITS4(1,D,sz1,sz2), regN, regD,
                               X1101, BITS4(N,0,M,0), regM);
               break;
            case ARMneon_VTBL:
               insn = XXXXXXXX(0xF, X0011, BITS4(1,D,1,1), regN, regD,
                               X1000, BITS4(N,0,M,0), regM);
               break;
            case ARMneon_VPADD:
               insn = XXXXXXXX(0xF, X0010, BITS4(0,D,sz1,sz2), regN, regD,
                               X1011, BITS4(N,Q,M,1), regM);
               break;
            case ARMneon_VPADDFP:
               insn = XXXXXXXX(0xF, X0011, BITS4(0,D,0,0), regN, regD,
                               X1101, BITS4(N,Q,M,0), regM);
               break;
            case ARMneon_VPMINU:
               insn = XXXXXXXX(0xF, X0011, BITS4(0,D,sz1,sz2), regN, regD,
                               X1010, BITS4(N,Q,M,1), regM);
               break;
            case ARMneon_VPMINS:
               insn = XXXXXXXX(0xF, X0010, BITS4(0,D,sz1,sz2), regN, regD,
                               X1010, BITS4(N,Q,M,1), regM);
               break;
            case ARMneon_VPMAXU:
               insn = XXXXXXXX(0xF, X0011, BITS4(0,D,sz1,sz2), regN, regD,
                               X1010, BITS4(N,Q,M,0), regM);
               break;
            case ARMneon_VPMAXS:
               insn = XXXXXXXX(0xF, X0010, BITS4(0,D,sz1,sz2), regN, regD,
                               X1010, BITS4(N,Q,M,0), regM);
               break;
            case ARMneon_VADDFP: /* VADD reg, reg, reg */
               insn = XXXXXXXX(0xF, X0010, BITS4(0,D,0,0), regN, regD,
                               X1101, BITS4(N,Q,M,0), regM);
               break;
            case ARMneon_VSUBFP: /* VADD reg, reg, reg */
               insn = XXXXXXXX(0xF, X0010, BITS4(0,D,1,0), regN, regD,
                               X1101, BITS4(N,Q,M,0), regM);
               break;
            case ARMneon_VABDFP: /* VABD reg, reg, reg */
               insn = XXXXXXXX(0xF, X0011, BITS4(0,D,1,0), regN, regD,
                               X1101, BITS4(N,Q,M,0), regM);
               break;
            case ARMneon_VMINF:
               insn = XXXXXXXX(0xF, X0010, BITS4(0,D,1,0), regN, regD,
                               X1111, BITS4(N,Q,M,0), regM);
               break;
            case ARMneon_VMAXF:
               insn = XXXXXXXX(0xF, X0010, BITS4(0,D,0,0), regN, regD,
                               X1111, BITS4(N,Q,M,0), regM);
               break;
            case ARMneon_VPMINF:
               insn = XXXXXXXX(0xF, X0011, BITS4(0,D,1,0), regN, regD,
                               X1111, BITS4(N,Q,M,0), regM);
               break;
            case ARMneon_VPMAXF:
               insn = XXXXXXXX(0xF, X0011, BITS4(0,D,0,0), regN, regD,
                               X1111, BITS4(N,Q,M,0), regM);
               break;
            case ARMneon_VRECPS:
               insn = XXXXXXXX(0xF, X0010, BITS4(0,D,0,0), regN, regD, X1111,
                               BITS4(N,Q,M,1), regM);
               break;
            case ARMneon_VCGTF:
               insn = XXXXXXXX(0xF, X0011, BITS4(0,D,1,0), regN, regD, X1110,
                               BITS4(N,Q,M,0), regM);
               break;
            case ARMneon_VCGEF:
               insn = XXXXXXXX(0xF, X0011, BITS4(0,D,0,0), regN, regD, X1110,
                               BITS4(N,Q,M,0), regM);
               break;
            case ARMneon_VCEQF:
               insn = XXXXXXXX(0xF, X0010, BITS4(0,D,0,0), regN, regD, X1110,
                               BITS4(N,Q,M,0), regM);
               break;
            case ARMneon_VRSQRTS:
               insn = XXXXXXXX(0xF, X0010, BITS4(0,D,1,0), regN, regD, X1111,
                               BITS4(N,Q,M,1), regM);
               break;
            default:
               goto bad;
         }
         *p++ = insn;
         goto done;
      }
      case ARMin_NShift: {
         UInt Q = i->ARMin.NShift.Q ? 1 : 0;
         UInt regD = (hregClass(i->ARMin.NShift.dst) == HRcVec128)
                       ? (qregNo(i->ARMin.NShift.dst) << 1)
                       : dregNo(i->ARMin.NShift.dst);
         UInt regM = (hregClass(i->ARMin.NShift.argL) == HRcVec128)
                       ? (qregNo(i->ARMin.NShift.argL) << 1)
                       : dregNo(i->ARMin.NShift.argL);
         UInt regN = (hregClass(i->ARMin.NShift.argR) == HRcVec128)
                       ? (qregNo(i->ARMin.NShift.argR) << 1)
                       : dregNo(i->ARMin.NShift.argR);
         UInt sz1 = i->ARMin.NShift.size >> 1;
         UInt sz2 = i->ARMin.NShift.size & 1;
         UInt D = regD >> 4;
         UInt N = regN >> 4;
         UInt M = regM >> 4;
         UInt insn;
         regD &= 0xF;
         regM &= 0xF;
         regN &= 0xF;
         switch (i->ARMin.NShift.op) {
            case ARMneon_VSHL:
               insn = XXXXXXXX(0xF, X0011, BITS4(0,D,sz1,sz2), regN, regD,
                               X0100, BITS4(N,Q,M,0), regM);
               break;
            case ARMneon_VSAL:
               insn = XXXXXXXX(0xF, X0010, BITS4(0,D,sz1,sz2), regN, regD,
                               X0100, BITS4(N,Q,M,0), regM);
               break;
            case ARMneon_VQSHL:
               insn = XXXXXXXX(0xF, X0011, BITS4(0,D,sz1,sz2), regN, regD,
                               X0100, BITS4(N,Q,M,1), regM);
               break;
            case ARMneon_VQSAL:
               insn = XXXXXXXX(0xF, X0010, BITS4(0,D,sz1,sz2), regN, regD,
                               X0100, BITS4(N,Q,M,1), regM);
               break;
            default:
               goto bad;
         }
         *p++ = insn;
         goto done;
      }
      case ARMin_NShl64: {
         HReg regDreg = i->ARMin.NShl64.dst;
         HReg regMreg = i->ARMin.NShl64.src;
         UInt amt     = i->ARMin.NShl64.amt;
         vassert(amt >= 1 && amt <= 63);
         vassert(hregClass(regDreg) == HRcFlt64);
         vassert(hregClass(regMreg) == HRcFlt64);
         UInt regD = dregNo(regDreg);
         UInt regM = dregNo(regMreg);
         UInt D    = (regD >> 4) & 1;
         UInt Vd   = regD & 0xF;
         UInt L    = 1;
         UInt Q    = 0; /* always 64-bit */
         UInt M    = (regM >> 4) & 1;
         UInt Vm   = regM & 0xF;
         UInt insn = XXXXXXXX(X1111,X0010, BITS4(1,D,(amt>>5)&1,(amt>>4)&1),
                              amt & 0xF, Vd, X0101, BITS4(L,Q,M,1), Vm);
         *p++ = insn;
         goto done;
      }
      case ARMin_NeonImm: {
         UInt Q = (hregClass(i->ARMin.NeonImm.dst) == HRcVec128) ? 1 : 0;
         UInt regD = Q ? (qregNo(i->ARMin.NeonImm.dst) << 1) :
                          dregNo(i->ARMin.NeonImm.dst);
         UInt D = regD >> 4;
         UInt imm = i->ARMin.NeonImm.imm->imm8;
         UInt tp = i->ARMin.NeonImm.imm->type;
         UInt j = imm >> 7;
         UInt imm3 = (imm >> 4) & 0x7;
         UInt imm4 = imm & 0xF;
         UInt cmode, op;
         UInt insn;
         regD &= 0xF;
         if (tp == 9)
            op = 1;
         else
            op = 0;
         switch (tp) {
            case 0:
            case 1:
            case 2:
            case 3:
            case 4:
            case 5:
               cmode = tp << 1;
               break;
            case 9:
            case 6:
               cmode = 14;
               break;
            case 7:
               cmode = 12;
               break;
            case 8:
               cmode = 13;
               break;
            case 10:
               cmode = 15;
               break;
            default:
               vpanic("ARMin_NeonImm");

         }
         insn = XXXXXXXX(0xF, BITS4(0,0,1,j), BITS4(1,D,0,0), imm3, regD,
                         cmode, BITS4(0,Q,op,1), imm4);
         *p++ = insn;
         goto done;
      }
      case ARMin_NCMovQ: {
         UInt cc = (UInt)i->ARMin.NCMovQ.cond;
         UInt qM = qregNo(i->ARMin.NCMovQ.src) << 1;
         UInt qD = qregNo(i->ARMin.NCMovQ.dst) << 1;
         UInt vM = qM & 0xF;
         UInt vD = qD & 0xF;
         UInt M  = (qM >> 4) & 1;
         UInt D  = (qD >> 4) & 1;
         vassert(cc < 16 && cc != ARMcc_AL && cc != ARMcc_NV);
         /* b!cc here+8: !cc A00 0000 */
         UInt insn = XXXXXXXX(cc ^ 1, 0xA, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0);
         *p++ = insn;
         /* vmov qD, qM */
         insn = XXXXXXXX(0xF, 0x2, BITS4(0,D,1,0),
                         vM, vD, BITS4(0,0,0,1), BITS4(M,1,M,1), vM);
         *p++ = insn;
         goto done;
      }
      case ARMin_Add32: {
         UInt regD = iregNo(i->ARMin.Add32.rD);
         UInt regN = iregNo(i->ARMin.Add32.rN);
         UInt imm32 = i->ARMin.Add32.imm32;
         vassert(regD != regN);
         /* MOV regD, imm32 */
         p = imm32_to_iregNo((UInt *)p, regD, imm32);
         /* ADD regD, regN, regD */
         UInt insn = XXXXXXXX(0xE, 0, X1000, regN, regD, 0, 0, regD);
         *p++ = insn;
         goto done;
      }

      case ARMin_EvCheck: {
         /* We generate:
               ldr  r12, [r8 + #4]   4 == offsetof(host_EvC_COUNTER)
               subs r12, r12, #1  (A1)
               str  r12, [r8 + #4]   4 == offsetof(host_EvC_COUNTER)
               bpl  nofail
               ldr  r12, [r8 + #0]   0 == offsetof(host_EvC_FAILADDR)
               bx   r12
              nofail:
         */
         UInt* p0 = p;
         p = do_load_or_store32(p, True/*isLoad*/, /*r*/12,
                                i->ARMin.EvCheck.amCounter);
         *p++ = 0xE25CC001; /* subs r12, r12, #1 */
         p = do_load_or_store32(p, False/*!isLoad*/, /*r*/12,
                                i->ARMin.EvCheck.amCounter);
         *p++ = 0x5A000001; /* bpl nofail */
         p = do_load_or_store32(p, True/*isLoad*/, /*r*/12,
                                i->ARMin.EvCheck.amFailAddr);
         *p++ = 0xE12FFF1C; /* bx r12 */
         /* nofail: */

         /* Crosscheck */
         vassert(evCheckSzB_ARM() == (UChar*)p - (UChar*)p0);
         goto done;
      }

      case ARMin_ProfInc: {
         /* We generate:
              (ctrP is unknown now, so use 0x65556555 in the
              expectation that a later call to LibVEX_patchProfCtr
              will be used to fill in the immediate fields once the
              right value is known.)
            movw r12, lo16(0x65556555)
            movt r12, lo16(0x65556555)
            ldr  r11, [r12]
            adds r11, r11, #1
            str  r11, [r12]
            ldr  r11, [r12+4]
            adc  r11, r11, #0
            str  r11, [r12+4]
         */
         p = imm32_to_iregNo_EXACTLY2(p, /*r*/12, 0x65556555);
         *p++ = 0xE59CB000;
         *p++ = 0xE29BB001;
         *p++ = 0xE58CB000;
         *p++ = 0xE59CB004;
         *p++ = 0xE2ABB000;
         *p++ = 0xE58CB004;
         /* Tell the caller .. */
         vassert(!(*is_profInc));
         *is_profInc = True;
         goto done;
      }

      /* ... */
      default:
         goto bad;
    }

  bad:
   ppARMInstr(i);
   vpanic("emit_ARMInstr");
   /*NOTREACHED*/

  done:
   vassert(((UChar*)p) - &buf[0] <= 32);
   return ((UChar*)p) - &buf[0];
}


/* How big is an event check?  See case for ARMin_EvCheck in
   emit_ARMInstr just above.  That crosschecks what this returns, so
   we can tell if we're inconsistent. */
Int evCheckSzB_ARM ( void )
{
   return 24;
}


/* NB: what goes on here has to be very closely coordinated with the
   emitInstr case for XDirect, above. */
VexInvalRange chainXDirect_ARM ( void* place_to_chain,
                                 void* disp_cp_chain_me_EXPECTED,
                                 void* place_to_jump_to )
{
   /* What we're expecting to see is:
        movw r12, lo16(disp_cp_chain_me_to_EXPECTED)
        movt r12, hi16(disp_cp_chain_me_to_EXPECTED)
        blx  r12
      viz
        <8 bytes generated by imm32_to_iregNo_EXACTLY2>
        E1 2F FF 3C
   */
   UInt* p = (UInt*)place_to_chain;
   vassert(0 == (3 & (HWord)p));
   vassert(is_imm32_to_iregNo_EXACTLY2(
              p, /*r*/12, (UInt)Ptr_to_ULong(disp_cp_chain_me_EXPECTED)));
   vassert(p[2] == 0xE12FFF3C);
   /* And what we want to change it to is either:
        (general case)
          movw r12, lo16(place_to_jump_to)
          movt r12, hi16(place_to_jump_to)
          bx   r12
        viz
          <8 bytes generated by imm32_to_iregNo_EXACTLY2>
          E1 2F FF 1C
      ---OR---
        in the case where the displacement falls within 26 bits
          b disp24; undef; undef
        viz
          EA <3 bytes == disp24>
          FF 00 00 00
          FF 00 00 00

      In both cases the replacement has the same length as the original.
      To remain sane & verifiable,
      (1) limit the displacement for the short form to
          (say) +/- 30 million, so as to avoid wraparound
          off-by-ones
      (2) even if the short form is applicable, once every (say)
          1024 times use the long form anyway, so as to maintain
          verifiability
   */

   /* This is the delta we need to put into a B insn.  It's relative
      to the start of the next-but-one insn, hence the -8.  */
   Long delta   = (Long)((UChar*)place_to_jump_to - (UChar*)p) - (Long)8;
   Bool shortOK = delta >= -30*1000*1000 && delta < 30*1000*1000;
   vassert(0 == (delta & (Long)3));

   static UInt shortCTR = 0; /* DO NOT MAKE NON-STATIC */
   if (shortOK) {
      shortCTR++; // thread safety bleh
      if (0 == (shortCTR & 0x3FF)) {
         shortOK = False;
         if (0)
            vex_printf("QQQ chainXDirect_ARM: shortCTR = %u, "
                       "using long form\n", shortCTR);
      }
   }

   /* And make the modifications. */
   if (shortOK) {
      Int simm24 = (Int)(delta >> 2);
      vassert(simm24 == ((simm24 << 8) >> 8));
      p[0] = 0xEA000000 | (simm24 & 0x00FFFFFF);
      p[1] = 0xFF000000;
      p[2] = 0xFF000000;
   } else {
      (void)imm32_to_iregNo_EXACTLY2(
               p, /*r*/12, (UInt)Ptr_to_ULong(place_to_jump_to));
      p[2] = 0xE12FFF1C;
   }

   VexInvalRange vir = {(HWord)p, 12};
   return vir;
}


/* NB: what goes on here has to be very closely coordinated with the
   emitInstr case for XDirect, above. */
VexInvalRange unchainXDirect_ARM ( void* place_to_unchain,
                                   void* place_to_jump_to_EXPECTED,
                                   void* disp_cp_chain_me )
{
   /* What we're expecting to see is:
        (general case)
          movw r12, lo16(place_to_jump_to_EXPECTED)
          movt r12, lo16(place_to_jump_to_EXPECTED)
          bx   r12
        viz
          <8 bytes generated by imm32_to_iregNo_EXACTLY2>
          E1 2F FF 1C
      ---OR---
        in the case where the displacement falls within 26 bits
          b disp24; undef; undef
        viz
          EA <3 bytes == disp24>
          FF 00 00 00
          FF 00 00 00
   */
   UInt* p = (UInt*)place_to_unchain;
   vassert(0 == (3 & (HWord)p));

   Bool valid = False;
   if (is_imm32_to_iregNo_EXACTLY2(
          p, /*r*/12, (UInt)Ptr_to_ULong(place_to_jump_to_EXPECTED))
       && p[2] == 0xE12FFF1C) {
      valid = True; /* it's the long form */
      if (0)
         vex_printf("QQQ unchainXDirect_ARM: found long form\n");
   } else
   if ((p[0] >> 24) == 0xEA && p[1] == 0xFF000000 && p[2] == 0xFF000000) {
      /* It's the short form.  Check the displacement is right. */
      Int simm24 = p[0] & 0x00FFFFFF;
      simm24 <<= 8; simm24 >>= 8;
      if ((UChar*)p + (simm24 << 2) + 8 == (UChar*)place_to_jump_to_EXPECTED) {
         valid = True;
         if (0)
            vex_printf("QQQ unchainXDirect_ARM: found short form\n");
      }
   }
   vassert(valid);

   /* And what we want to change it to is:
        movw r12, lo16(disp_cp_chain_me)
        movt r12, hi16(disp_cp_chain_me)
        blx  r12
      viz
        <8 bytes generated by imm32_to_iregNo_EXACTLY2>
        E1 2F FF 3C
   */
   (void)imm32_to_iregNo_EXACTLY2(
            p, /*r*/12, (UInt)Ptr_to_ULong(disp_cp_chain_me));
   p[2] = 0xE12FFF3C;
   VexInvalRange vir = {(HWord)p, 12};
   return vir;
}


/* Patch the counter address into a profile inc point, as previously
   created by the ARMin_ProfInc case for emit_ARMInstr. */
VexInvalRange patchProfInc_ARM ( void*  place_to_patch,
                                 ULong* location_of_counter )
{
   vassert(sizeof(ULong*) == 4);
   UInt* p = (UInt*)place_to_patch;
   vassert(0 == (3 & (HWord)p));
   vassert(is_imm32_to_iregNo_EXACTLY2(p, /*r*/12, 0x65556555));
   vassert(p[2] == 0xE59CB000);
   vassert(p[3] == 0xE29BB001);
   vassert(p[4] == 0xE58CB000);
   vassert(p[5] == 0xE59CB004);
   vassert(p[6] == 0xE2ABB000);
   vassert(p[7] == 0xE58CB004);
   imm32_to_iregNo_EXACTLY2(p, /*r*/12,
                            (UInt)Ptr_to_ULong(location_of_counter));
   VexInvalRange vir = {(HWord)p, 8};
   return vir;
}


#undef BITS4
#undef X0000
#undef X0001
#undef X0010
#undef X0011
#undef X0100
#undef X0101
#undef X0110
#undef X0111
#undef X1000
#undef X1001
#undef X1010
#undef X1011
#undef X1100
#undef X1101
#undef X1110
#undef X1111
#undef XXXXX___
#undef XXXXXX__
#undef XXX___XX
#undef XXXXX__X
#undef XXXXXXXX
#undef XX______

/*---------------------------------------------------------------*/
/*--- end                                     host_arm_defs.c ---*/
/*---------------------------------------------------------------*/