/*
 * PowerPC table for ncg
 *
 * David Given created this table.
 * George Koehler made many changes in years 2016 to 2018.
 *
 * This back end provides 4-byte integers, 4-byte floats, and 8-byte
 * floats.  It should provide enough of EM for the ACK's compilers.
 *  - It doesn't provide "mon" (monitor call) nor "lor 2", "str 2"
 *    (heap pointer).  Programs should call procedures in libsys to
 *    make system calls or allocate heap memory.
 *  - It generates only a few EM traps:
 *     - EARRAY from aar, lar, sar
 *     - ERANGE from rck
 *     - ECASE from csa, csb
 *  - It uses floating-point registers to move 8-byte values that
 *    aren't floats.  This might cause extra FPU context switches in
 *    programs that don't use floating point.
 *
 * The EM stack is less than optimal for PowerPC, and incompatible
 * with the calling conventions of other compilers (like gcc).
 *  - EM and ncg use the stack to pass parameters to procedures.  For
 *    PowerPC, this is probably slower than passing them in registers.
 *  - This back end misaligns some 8-byte floats, because EM's stack
 *    has only 4-byte alignment.  (This kind of misalignment also
 *    happened in IBM's AIX and Apple's Mac OS, where data structures
 *    had 8-byte floats with only 4-byte alignment.)
 */

EM_WSIZE = 4
EM_PSIZE = 4
EM_BSIZE = 8    /* two words saved in call frame */

FP_OFFSET = 0   /* Offset of saved FP relative to our FP */
PC_OFFSET = 4   /* Offset of saved PC relative to our FP */

#define COMMENT(n) /* comment {LABEL, n} */

#define nicesize(x) ((x)==1 || (x)==2 || (x)==4 || (x)==8)

#define smalls(n) sfit(n, 16)
#define smallu(n) ufit(n, 16)

/* Finds FRAME_V tokens that overlap myoff, mysize. */
#define fover(myoff, mysize) (%off+%size>(myoff) && %off<((myoff)+(mysize)))

/* Checks if we can use {LXFRAME, x}. */
#define nicelx(x) ((x)>=1 && (x)<=0x8000)

#define lo(n) ((n) & 0xFFFF)
#define hi(n) (((n)>>16) & 0xFFFF)

/* Use these for instructions that treat the low half as signed --- his()
 * includes a modifier to produce the correct value when the low half gets
 * sign extended. Er, do make sure you load the low half second. */
#define los(n) (lo(n) | (((0-(lo(n)>>15)) & ~0xFFFF)))
#define his(n) ((hi(n) + (lo(n)>>15)) & 0xFFFF)


PROPERTIES

	GPR             /* general-purpose register */
	SPFP            /* sp or fp */
	REG             /* allocatable GPR */
	REG3            /* coercion to r3 */

	FPR(8)          /* floating-point register */
	FREG(8)         /* allocatable FPR */
	FSREG           /* allocatable single-precision FPR */

	SPR             /* special-purpose register */
	CR              /* condition register */


REGISTERS

	/*
	 * We use r1 as stack pointer and r2 as frame pointer.
	 * Our assembler has aliases sp -> r1 and fp -> r2.
	 *
	 * We preserve r13 to r31 and f14 to f31 across function
	 * calls to mimic other compilers (like gcc).  See
	 *  - http://refspecs.linuxbase.org/elf/elfspec_ppc.pdf
	 *  - https://github.com/ryanarn/powerabi -> chap3-elf32abi.sgml
	 *  - Apple's "32-bit PowerPC Function Calling Conventions"
	 *
	 * When ncg allocates regvars, it seems to start with the last
	 * register in the first class.  To encourage ncg to allocate
	 * them from r31 down, we list them in one class as
	 *   r13, r14, ..., r31: GPR, REG regvar(reg_any).
	 */

	r0, r12                           : GPR.
	sp, fp                            : GPR, SPFP.
	r3                                : GPR, REG, REG3.
	r4, r5, r6, r7, r8, r9, r10, r11  : GPR, REG.

	r13, r14, r15, r16, r17, r18, r19, r20, r21, r22, r23, r24,
	r25, r26, r27, r28, r29, r30, r31
	  : GPR, REG regvar(reg_any).

	f0          : FPR.

	f1, f2, f3, f4, f5, f6, f7, f8, f9, f10, f11, f12, f13
	  : FPR, FREG.

	f14, f15, f16, f17, f18, f19, f20, f21, f22, f23, f24, f25,
	f26, f27, f28, f29, f30, f31
	  : FPR, FREG regvar(reg_float).

	fs1("f1")=f1, fs2("f2")=f2, fs3("f3")=f3, fs4("f4")=f4,
	fs5("f5")=f5, fs6("f6")=f6, fs7("f7")=f7, fs8("f8")=f8,
	fs9("f9")=f9, fs10("f10")=f10, fs11("f11")=f11, fs12("f12")=f12,
	fs13("f13")=f13
	  : FSREG.

	/* reglap: reg_float may have subregister of different size */
	fs14("f14")=f14, fs15("f15")=f15, fs16("f16")=f16, fs17("f17")=f17,
	fs18("f18")=f18, fs19("f19")=f19, fs20("f20")=f20, fs21("f21")=f21,
	fs22("f22")=f22, fs23("f23")=f23, fs24("f24")=f24, fs25("f25")=f25,
	fs26("f26")=f26, fs27("f27")=f27, fs28("f28")=f28, fs29("f29")=f29,
	fs30("f30")=f30, fs31("f31")=f31
	  : FSREG regvar(reg_float).

	lr, ctr     : SPR.
	cr0         : CR.   /* We use cr0, ignore cr1 to cr7. */

	/* The stacking rules can't allocate registers.  We use these
	 * scratch registers to stack tokens.
	 */
#define RSCRATCH r0
#define FSCRATCH f0


TOKENS

/* Primitives */

	C /* constant */   = { INT val; }             4    val.
	LABEL              = { ADDR adr; }            4    adr.
	LABEL_HI           = { ADDR adr; }            4    "hi16[" adr "]".
	LABEL_HA           = { ADDR adr; }            4    "ha16[" adr "]".
	LABEL_LO           = { ADDR adr; }            4    "lo16[" adr "]".
	LOCAL              = { INT off; }             4    ">>> BUG IN LOCAL".
	DLOCAL             = { INT off; }             8    ">>> BUG IN DLOCAL".

/* Allows us to use regvar() to refer to registers */

	REG_EXPR           = { REG reg; }             4    reg.
	FREG_EXPR          = { FREG reg; }            8    reg.
	FSREG_EXPR         = { FSREG reg; }           4    reg.

/* Constants on the stack */

	CONST_N8000        = { INT val; }             4    val.
	CONST_N7FFF_N0001  = { INT val; }             4    val.
	CONST_0000_7FFF    = { INT val; }             4    val.
	CONST_8000         = { INT val; }             4    val.
	CONST_8001_FFFF    = { INT val; }             4    val.
	CONST_HI_ZR        = { INT val; }             4    val.
	CONST_HI_LO        = { INT val; }             4    val.

/* Expression partial results */

	SEX_B       = { GPR reg; }             4.   /* sign extension */
	SEX_H       = { GPR reg; }             4.

	SUM_RIS     = { GPR reg; INT offhi; }  4.   /* reg + (offhi << 16) */
	SUM_RC      = { GPR reg; INT off; }    4.   /* reg + off */
	SUM_RL      = { GPR reg; ADDR adr; }   4.   /* reg + lo16[adr] */
	SUM_RR      = { GPR reg1; GPR reg2; }  4.   /* reg1 + reg2 */

	SUB_CR      = { INT val; GPR reg; }    4.   /* val - reg */
	SUB_RR      = { GPR reg1; GPR reg2; }  4.   /* reg1 - reg2 */
	NEG_R       = { GPR reg; }             4.   /* -reg */
	MUL_RC      = { GPR reg; INT val; }    4.   /* reg * val */
	MUL_RR      = { GPR reg1; GPR reg2; }  4.   /* reg1 * reg2 */
	DIV_RR      = { GPR reg1; GPR reg2; }  4.   /* reg1 / reg2 signed */
	DIV_RR_U    = { GPR reg1; GPR reg2; }  4.   /* reg1 / reg2 unsigned */

/* Indirect loads and stores */

	IND_RC_B    = { GPR reg; INT off; }    4    off "(" reg ")".
	IND_RL_B    = { GPR reg; ADDR adr; }   4    "lo16[" adr "](" reg ")".
	IND_RR_B    = { GPR reg1; GPR reg2; }  4.
	IND_RC_H    = { GPR reg; INT off; }    4    off "(" reg ")".
	IND_RL_H    = { GPR reg; ADDR adr; }   4    "lo16[" adr "](" reg ")".
	IND_RR_H    = { GPR reg1; GPR reg2; }  4.
	IND_RC_H_S  = { GPR reg; INT off; }    4    off "(" reg ")".
	IND_RL_H_S  = { GPR reg; ADDR adr; }   4    "lo16[" adr "](" reg ")".
	IND_RR_H_S  = { GPR reg1; GPR reg2; }  4.
	IND_RC_W    = { GPR reg; INT off; }    4    off "(" reg ")".
	IND_RL_W    = { GPR reg; ADDR adr; }   4    "lo16[" adr "](" reg ")".
	IND_RR_W    = { GPR reg1; GPR reg2; }  4.
	IND_RC_D    = { GPR reg; INT off; }    8    off "(" reg ")".
	IND_RL_D    = { GPR reg; ADDR adr; }   8    "lo16[" adr "](" reg ")".
	IND_RR_D    = { GPR reg1; GPR reg2; }  8.

/* Local variables in frame */

	FRAME_B     = { INT level; GPR reg; INT off; INT size; }
	                                       4    off "(" reg ")".
	FRAME_H     = { INT level; GPR reg; INT off; INT size; }
	                                       4    off "(" reg ")".
	FRAME_H_S   = { INT level; GPR reg; INT off; INT size; }
	                                       4    off "(" reg ")".
	FRAME_W     = { INT level; GPR reg; INT off; INT size; }
	                                       4    off "(" reg ")".
	FRAME_D     = { INT level; GPR reg; INT off; INT size; }
	                                       8    off "(" reg ")".

	LXFRAME     = { INT level; }           4.

/* Bitwise logic */

	NOT_R       = { GPR reg; }             4.   /* ~reg */
	AND_RIS     = { GPR reg; INT valhi; }  4.
	AND_RC      = { GPR reg; INT val; }    4.
	AND_RR      = { GPR reg1; GPR reg2; }  4.
	ANDC_RR     = { GPR reg1; GPR reg2; }  4.   /* reg1 & ~reg2 */
	OR_RIS      = { GPR reg; INT valhi; }  4.
	OR_RC       = { GPR reg; INT val; }    4.
	OR_RR       = { GPR reg1; GPR reg2; }  4.
	ORC_RR      = { GPR reg1; GPR reg2; }  4.   /* reg1 | ~reg2 */
	XOR_RIS     = { GPR reg; INT valhi; }  4.
	XOR_RC      = { GPR reg; INT val; }    4.
	XOR_RR      = { GPR reg1; GPR reg2; }  4.
	NAND_RR     = { GPR reg1; GPR reg2; }  4.   /* ~(reg1 & reg2) */
	NOR_RR      = { GPR reg1; GPR reg2; }  4.   /* ~(reg1 | reg2) */
	EQV_RR      = { GPR reg1; GPR reg2; }  4.   /* ~(reg1 ^ reg2) */

/* Comparisons */

	COND_RC            = { GPR reg; INT val; }    4.
	COND_RR            = { GPR reg1; GPR reg2; }  4.
	CONDL_RC           = { GPR reg; INT val; }    4.
	CONDL_RR           = { GPR reg1; GPR reg2; }  4.
	COND_FS            = { FSREG reg1; FSREG reg2; } 4.
	COND_FD            = { FREG reg1; FREG reg2; }   4.

	XEQ                = { GPR reg; }             4.
	XNE                = { GPR reg; }             4.
	XGT                = { GPR reg; }             4.
	XGE                = { GPR reg; }             4.
	XLT                = { GPR reg; }             4.
	XLE                = { GPR reg; }             4.


SETS

	/* signed 16-bit integer */
	CONST2          = CONST_N8000 + CONST_N7FFF_N0001 + CONST_0000_7FFF.
	/* integer that, when negated, fits signed 16-bit */
	CONST2_WHEN_NEG = CONST_N7FFF_N0001 + CONST_0000_7FFF + CONST_8000.
	/* unsigned 16-bit integer */
	UCONST2         = CONST_0000_7FFF + CONST_8000 + CONST_8001_FFFF.
	/* any constant on stack */
	CONST_STACK     = CONST_N8000 + CONST_N7FFF_N0001 + CONST_0000_7FFF +
	                  CONST_8000 + CONST_8001_FFFF +
			  CONST_HI_ZR + CONST_HI_LO.

	CONST           = C + CONST_STACK.

	SET_RC_B        = IND_RC_B + IND_RL_B + FRAME_B.
	SET_RC_H        = IND_RC_H + IND_RL_H + FRAME_H.
	SET_RC_H_S      = IND_RC_H_S + IND_RL_H_S + FRAME_H_S.
	SET_RC_W        = IND_RC_W + IND_RL_W + FRAME_W.
	SET_RC_D        = IND_RC_D + IND_RL_D + FRAME_D.

	IND_ALL_B       = IND_RC_B + IND_RL_B + IND_RR_B.
	IND_ALL_H       = IND_RC_H + IND_RL_H + IND_RR_H +
	                  IND_RC_H_S + IND_RL_H_S + IND_RR_H_S.
	IND_ALL_W       = IND_RC_W + IND_RL_W + IND_RR_W.
	IND_ALL_D       = IND_RC_D + IND_RL_D + IND_RR_D.
	IND_V           = IND_ALL_B + IND_ALL_H + IND_ALL_W + IND_ALL_D.

	FRAME_V         = FRAME_B + FRAME_H + FRAME_H_S + FRAME_W + FRAME_D.

	/* anything killed by sti (store indirect) */
	MEMORY          = IND_V + FRAME_V.

	/* any integer from stack that we can easily move to GPR */
	INT_W   = SPFP + REG + CONST_STACK + SEX_B + SEX_H +
	          SUM_RIS + SUM_RC + SUM_RL + SUM_RR +
	          SUB_CR + SUB_RR + NEG_R +
	          MUL_RC + MUL_RR + DIV_RR + DIV_RR_U +
	          IND_ALL_B + IND_ALL_H + IND_ALL_W +
	          FRAME_B + FRAME_H + FRAME_H_S + FRAME_W +
	          NOT_R + AND_RIS + AND_RC + AND_RR + ANDC_RR +
	          OR_RIS + OR_RC + OR_RR + ORC_RR +
	          XOR_RIS + XOR_RC + XOR_RR + NAND_RR + NOR_RR + EQV_RR +
	          XEQ + XNE + XGT + XGE + XLT + XLE.

	FLOAT_D = FREG + IND_ALL_D + FRAME_D.
	FLOAT_W = FSREG + IND_ALL_W + FRAME_W.


INSTRUCTIONS

  /* We give time as cycles of total latency from Freescale
   * Semiconductor, MPC7450 RISC Microprocessor Family Reference
   * Manual, Rev. 5, section 6.6.
   *
   * We have only 4-byte alignment for doubles; 8-byte alignment is
   * optimal.  We guess the misalignment penalty by adding 1 cycle to
   * the cost of loading or storing a double:
   *   lfd lfdu lfdx: 4 -> 5
   *   stfd stfdu stfdx: 3 -> 4
   */
  cost(4, 1) /* space, time */

  add             GPR:wo, GPR:ro, GPR:ro.
  addX "add."     GPR:wo:cc, GPR:ro, GPR:ro.
  addi            GPR:wo, GPR:ro, CONST+LABEL_LO:ro.
    li            GPR:wo, CONST:ro.
  addis           GPR:wo, GPR:ro, CONST+LABEL_HI+LABEL_HA:ro.
    lis           GPR:wo, CONST+LABEL_HI+LABEL_HA:ro.
  and             GPR:wo, GPR:ro, GPR:ro.
  andc            GPR:wo, GPR:ro, GPR:ro.
  andiX  "andi."  GPR:wo:cc, GPR:ro, CONST:ro.
  andisX "andis." GPR:wo:cc, GPR:ro, CONST:ro.
  b               LABEL:ro.
  bc              CONST:ro, CONST:ro, LABEL:ro.
    bdnz          LABEL:ro.
    beq           LABEL:ro.
    bne           LABEL:ro.
    bgt           LABEL:ro.
    bge           LABEL:ro.
    blt           LABEL:ro.
    ble           LABEL:ro.
    bxx           LABEL:ro. /* dummy */
  bcctr           CONST:ro, CONST:ro, CONST:ro.
    bctr.
  bcctrl          CONST:ro, CONST:ro, CONST:ro.
    bctrl.
  bclr            CONST:ro, CONST:ro, CONST:ro.
    blr.
  bl              LABEL:ro.
  cmp             CR:wo, CONST:ro, GPR:ro, GPR:ro kills :cc.
    cmpw          GPR:ro, GPR:ro kills :cc.
  cmpi            CR:wo, CONST:ro, GPR:ro, CONST:ro kills :cc.
    cmpwi         GPR:ro, CONST:ro kills :cc.
  cmpl            CR:wo, CONST:ro, GPR:ro, GPR:ro kills :cc.
    cmplw         GPR:ro, GPR:ro kills :cc.
  cmpli           CR:wo, CONST:ro, GPR:ro, CONST:ro kills :cc.
    cmplwi        GPR:ro, CONST:ro kills :cc.
  divw            GPR:wo, GPR:ro, GPR:ro cost(4, 23).
  divwu           GPR:wo, GPR:ro, GPR:ro cost(4, 23).
  eqv             GPR:wo, GPR:ro, GPR:ro.
  extsb           GPR:wo, GPR:ro.
  extsh           GPR:wo, GPR:ro.
  fadd            FREG+DLOCAL:wo, FREG:ro, FREG:ro cost(4, 5).
  fadds           FSREG+LOCAL:wo, FSREG:ro, FSREG:ro cost(4, 5).
  fcmpo           CR:wo, FREG:ro, FREG:ro cost(4, 5).
  fcmpo           CR:wo, FSREG:ro, FSREG:ro cost(4, 5).
  fctiwz          FREG:wo, FREG:ro cost(4, 5).
  fdiv            FREG+DLOCAL:wo, FREG:ro, FREG:ro cost(4, 35).
  fdivs           FSREG+LOCAL:wo, FSREG:ro, FSREG:ro cost(4, 21).
  fmr             FPR:wo, FPR:ro cost(4, 5).
  fmr             FSREG:wo, FSREG:ro cost(4, 5).
  fmul            FREG+DLOCAL:wo, FREG:ro, FREG:ro cost(4, 5).
  fmuls           FSREG+LOCAL:wo, FSREG:ro, FSREG:ro cost(4, 5).
  fneg            FREG+DLOCAL:wo, FREG:ro cost(4, 5).
  fneg            FSREG+LOCAL:wo, FSREG:ro cost(4, 5).
  frsp            FSREG+LOCAL:wo, FREG:ro cost(4, 5).
  fsub            FREG+DLOCAL:wo, FREG:ro, FREG:ro cost(4, 5).
  fsubs           FSREG+LOCAL:wo, FSREG:ro, FSREG:ro cost(4, 5).
  lbz             GPR:wo, SET_RC_B:ro cost(4, 3).
  lbzx            GPR:wo, GPR:ro, GPR:ro cost(4, 3).
  lfd             FPR+DLOCAL:wo, SET_RC_D:ro cost(4, 5).
  lfdu            FPR:wo, IND_RC_D:rw cost(4, 5).
  lfdx            FPR:wo, GPR:ro, GPR:ro cost(4, 5).
  lfs             FSREG+LOCAL:wo, SET_RC_W:ro cost(4, 4).
  lfsu            FSREG:wo, IND_RC_W:rw cost(4, 4).
  lfsx            FSREG:wo, GPR:ro, GPR:ro cost(4, 4).
  lha             GPR:wo, SET_RC_H_S:ro cost(4, 3).
  lhax            GPR:wo, GPR:ro, GPR:ro cost(4, 3).
  lhz             GPR:wo, SET_RC_H:ro cost(4, 3).
  lhzx            GPR:wo, GPR:ro, GPR:ro cost(4, 3).
  lwz             GPR+LOCAL:wo, SET_RC_W:ro cost(4, 3).
  lwzu            GPR:wo, IND_RC_W:rw cost(4, 3).
  lwzx            GPR:wo, GPR:ro, GPR:ro cost(4, 3).
  mfcr            GPR:wo cost(4,2).
  mfspr           GPR:wo, SPR:ro cost(4, 3).
  mtspr           SPR:wo, GPR:ro cost(4, 2).
  mulli           GPR:wo, GPR:ro, CONST:ro cost(4, 3).
  mullw           GPR:wo, GPR:ro, GPR:ro cost(4, 4).
  nand            GPR:wo, GPR:ro, GPR:ro.
  neg             GPR:wo, GPR:ro.
  nor             GPR:wo, GPR:ro, GPR:ro.
  or              GPR:wo, GPR:ro, GPR:ro.
    mr            GPR:wo, GPR:ro.
  orX "or."       GPR:wo:cc, GPR:ro, GPR:ro.
    mrX_readonly "mr." GPR:ro:cc, GPR:ro.
  orc             GPR:wo, GPR:ro, GPR:ro.
  ori             GPR:wo, GPR:ro, CONST+LABEL_LO:ro.
  oris            GPR:wo, GPR:ro, CONST:ro.
  rlwinm          GPR:wo, GPR:ro, CONST:ro, CONST:ro, CONST:ro.
    extlwi        GPR:wo, GPR:ro, CONST:ro, CONST:ro.
    extrwi        GPR:wo, GPR:ro, CONST:ro, CONST:ro.
    rotlwi        GPR+LOCAL:wo, GPR:ro, CONST:ro.
    rotrwi        GPR+LOCAL:wo, GPR:ro, CONST:ro.
    slwi          GPR+LOCAL:wo, GPR:ro, CONST:ro.
    srwi          GPR+LOCAL:wo, GPR:ro, CONST:ro.
  rlwnm           GPR:wo, GPR:ro, GPR:ro, CONST:ro, CONST:ro.
    rotlw         GPR+LOCAL:wo, GPR:ro, GPR:ro.
  slw             GPR+LOCAL:wo, GPR:ro, GPR:ro.
  sraw            GPR+LOCAL:wo, GPR:ro, GPR:ro /* kills xer */ cost(4, 2).
  srawi           GPR+LOCAL:wo, GPR:ro, CONST:ro /* kills xer */ cost(4, 2).
  srw             GPR+LOCAL:wo, GPR:ro, GPR:ro.
  stb             GPR:ro, SET_RC_B:rw cost(4, 3).
  stbx            GPR:ro, GPR:ro, GPR:ro cost(4, 3).
  stfd            FPR:ro, SET_RC_D:rw cost(4, 4).
  stfdu           FPR:ro, IND_RC_D:rw cost(4, 4).
  stfdx           FPR:ro, GPR:ro, GPR:ro cost(4, 4).
  stfs            FSREG:ro, SET_RC_W:rw cost(4, 3).
  stfsu           FSREG:ro, IND_RC_W:rw cost(4, 3).
  stfsx           FSREG:ro, GPR:ro, GPR:ro cost(4, 3).
  sth             GPR:ro, SET_RC_H:rw cost(4, 3).
  sthx            GPR:ro, GPR:ro, GPR:ro cost(4, 3).
  stw             GPR:ro, SET_RC_W:rw cost(4, 3).
  stwx            GPR:ro, GPR:ro, GPR:ro cost(4, 3).
  stwu            GPR:ro, IND_RC_W:rw cost(4, 3).
  subf            GPR:wo, GPR:ro, GPR:ro.
  subfic          GPR:wo, GPR:ro, CONST:ro /* kills xer */.
  xor             GPR:wo, GPR:ro, GPR:ro.
  xori            GPR:wo, GPR:ro, CONST:ro.
  xoris           GPR:wo, GPR:ro, CONST:ro.

  bug ">>> BUG"           LABEL:ro cost(0, 0).
  comment "!"             LABEL:ro cost(0, 0).


MOVES

	from GPR to GPR
		gen mr %2, %1

	from FSREG to FSREG
		gen fmr %2, %1

	from FPR to FPR
		gen fmr %2, %1

/* Constants */

	from CONST smalls(%val) to GPR
		gen
			COMMENT("move CONST->GPR smalls")
			li %2, %1

	from CONST lo(%val)==0 to GPR
		gen
			COMMENT("move CONST->GPR shifted")
			lis %2, {C, hi(%1.val)}

	from CONST to GPR
		gen
			COMMENT("move CONST->GPR")
			lis %2, {C, hi(%1.val)}
			ori %2, %2, {C, lo(%1.val)}
			/* Can't use addi %2, %2, {C, los(%1.val)}
			 * because %2 might be R0. */

	from LABEL to GPR
		gen
			COMMENT("move LABEL->GPR")
			lis %2, {LABEL_HI, %1.adr}
			ori %2, %2, {LABEL_LO, %1.adr}

	from LABEL_HA to GPR
		gen lis %2, %1

/* Sign extension */

	from SEX_B to GPR
		gen extsb %2, %1.reg

	from SEX_H to GPR
		gen extsh %2, %1.reg

/* Register + something */

	from SUM_RIS to GPR
		gen addis %2, %1.reg, {C, %1.offhi}

	from SUM_RC to GPR
		gen addi %2, %1.reg, {C, %1.off}

	from SUM_RL to GPR
		gen addi %2, %1.reg, {LABEL_LO, %1.adr}

	from SUM_RR to GPR
		gen add %2, %1.reg1, %1.reg2

/* Other arithmetic */

	from SUB_CR to GPR
		/* val - reg -> subtract reg from val */
		gen subfic %2, %1.reg, {C, %1.val}

	from SUB_RR to GPR
		/* reg1 - reg2 -> subtract reg2 from reg1 */
		gen subf %2, %1.reg2, %1.reg1

	from NEG_R to GPR
		gen neg %2, %1.reg

	from MUL_RC to GPR
		gen mulli %2, %1.reg, {C, %1.val}

	from MUL_RR to GPR
		gen mullw %2, %1.reg1, %1.reg2

	from DIV_RR to GPR
		gen divw %2, %1.reg1, %1.reg2

	from DIV_RR_U to GPR
		gen divwu %2, %1.reg1, %1.reg2

/* Read byte */

	from SET_RC_B to GPR
		gen lbz %2, %1

	from IND_RR_B to GPR
		gen lbzx %2, %1.reg1, %1.reg2

/* Write byte */

	from GPR to SET_RC_B
		gen stb %1, %2

	from GPR to IND_RR_B
		gen stbx %1, %2.reg1, %2.reg2

/* Read halfword (short) */

	from SET_RC_H to GPR
		gen lhz %2, %1

	from IND_RR_H to GPR
		gen lhzx %2, %1.reg1, %1.reg2

	from SET_RC_H_S to GPR
		gen lha %2, %1

	from IND_RR_H_S to GPR
		gen lhax %2, %1.reg1, %1.reg2

/* Write halfword */

	from GPR to SET_RC_H
		gen sth %1, %2

	from GPR to IND_RR_H
		gen sthx %1, %2.reg1, %2.reg2

/* Read word */

	from SET_RC_W to GPR
		gen lwz %2, %1

	from IND_RR_W to GPR
		gen lwzx %2, %1.reg1, %1.reg2

	from SET_RC_W to FSREG
		gen lfs %2, %1

	from IND_RR_W to FSREG
		gen lfsx %2, %1.reg1, %1.reg2

/* Write word */

	from GPR to SET_RC_W
		gen stw %1, %2

	from GPR to IND_RR_W
		gen stwx %1, %2.reg1, %2.reg2

	from FSREG to SET_RC_W
		gen stfs %1, %2

	from FSREG to IND_RR_W
		gen stfsx %1, %2.reg1, %2.reg2

/* Read double */

	from SET_RC_D to FPR
		gen lfd %2, %1

	from IND_RR_D to FPR
		gen lfdx %2, %1.reg1, %1.reg2

/* Write double */

	from FPR to SET_RC_D
		gen stfd %1, %2

	from FPR to IND_RR_D
		gen stfdx %1, %2.reg1, %2.reg2

/* LXFRAME is a lexical frame from the static chain.  We define a move
   so "uses REG={LXFRAME, $1}" may find a register with the same
   frame, and not repeat the move.  This move can't search for a REG
   with {LXFRAME, $1-1}, but must always start from fp.  The static
   chain, if it exists, is the argument at fp + EM_BSIZE. */

	from LXFRAME %level==1 to REG
		gen	lwz %2, {IND_RC_W, fp, EM_BSIZE}
	from LXFRAME %level==2 to REG
		gen	lwz %2, {IND_RC_W, fp, EM_BSIZE}
			/* PowerPC can't add r0 + EM_BSIZE,
			 * so %2 must not be r0. */
			lwz %2, {IND_RC_W, %2, EM_BSIZE}
	from LXFRAME %level==3 to REG
		gen	lwz %2, {IND_RC_W, fp, EM_BSIZE}
			lwz %2, {IND_RC_W, %2, EM_BSIZE}
			lwz %2, {IND_RC_W, %2, EM_BSIZE}
	from LXFRAME %level==4 to REG
		gen	lwz %2, {IND_RC_W, fp, EM_BSIZE}
			lwz %2, {IND_RC_W, %2, EM_BSIZE}
			lwz %2, {IND_RC_W, %2, EM_BSIZE}
			lwz %2, {IND_RC_W, %2, EM_BSIZE}
	from LXFRAME to REG  /* assuming %level in 2 to 0x8000 */
		gen	li %2, {C, %1.level-1}
			mtspr ctr, %2
			lwz %2, {IND_RC_W, fp, EM_BSIZE}
		1:	lwz %2, {IND_RC_W, %2, EM_BSIZE}
			bdnz {LABEL, "1b"}

/* Logicals */

	from NOT_R to GPR
		gen nor %2, %1.reg, %1.reg

	from AND_RIS to GPR
		gen andisX %2, %1.reg, {C, %1.valhi}

	from AND_RC to GPR
		gen andiX %2, %1.reg, {C, %1.val}

	from AND_RR to GPR
		gen and %2, %1.reg1, %1.reg2

	from ANDC_RR to GPR
		gen andc %2, %1.reg1, %1.reg2

	from OR_RIS to GPR
		gen oris %2, %1.reg, {C, %1.valhi}

	from OR_RC to GPR
		gen ori %2, %1.reg, {C, %1.val}

	from OR_RR to GPR
		gen or %2, %1.reg1, %1.reg2

	from ORC_RR to GPR
		gen orc %2, %1.reg1, %1.reg2

	from XOR_RIS to GPR
		gen xoris %2, %1.reg, {C, %1.valhi}

	from XOR_RC to GPR
		gen xori %2, %1.reg, {C, %1.val}

	from XOR_RR to GPR
		gen xor %2, %1.reg1, %1.reg2

	from NAND_RR to GPR
		gen nand %2, %1.reg1, %1.reg2

	from NOR_RR to GPR
		gen nor %2, %1.reg1, %1.reg2

	from EQV_RR to GPR
		gen eqv %2, %1.reg1, %1.reg2

/* Conditions */

	/* Compare values, then copy cr0 to GPR. */

	from COND_RC to GPR
		gen
			cmpwi %1.reg, {C, %1.val}
			mfcr %2

	from COND_RR to GPR
		gen
			cmpw %1.reg1, %1.reg2
			mfcr %2

	from CONDL_RC to GPR
		gen
			cmplwi %1.reg, {C, %1.val}
			mfcr %2

	from CONDL_RR to GPR
		gen
			cmplw %1.reg1, %1.reg2
			mfcr %2

	from COND_FS to GPR
		gen
			fcmpo cr0, %1.reg1, %1.reg2
			mfcr %2

	from COND_FD to GPR
		gen
			fcmpo cr0, %1.reg1, %1.reg2
			mfcr %2

	/* Given a copy of cr0 in %1.reg, extract a condition bit
	 * (lt, gt, eq) and perhaps flip it.
	 */

	from XEQ to GPR
		gen
			extrwi %2, %1.reg, {C, 1}, {C, 2}

	from XNE to GPR
		gen
			extrwi %2, %1.reg, {C, 1}, {C, 2}
			xori %2, %2, {C, 1}

	from XGT to GPR
		gen
			extrwi %2, %1.reg, {C, 1}, {C, 1}

	from XGE to GPR
		gen
			extrwi %2, %1.reg, {C, 1}, {C, 0}
			xori %2, %2, {C, 1}

	from XLT to GPR
		gen
			extrwi %2, %1.reg, {C, 1}, {C, 0}

	from XLE to GPR
		gen
			extrwi %2, %1.reg, {C, 1}, {C, 1}
			xori %2, %2, {C, 1}

/* REG_EXPR exists solely to allow us to use regvar() (which can only
   be used in an expression) as a register constant.  We can then use
   our moves to GPR or REG to set register variables.  This is easier
   than defining moves to LOCAL, and avoids confusion between GPR and
   FSREG in LOCAL. */

	from INT_W + LXFRAME to REG_EXPR
		gen move %1, %2.reg

	from FLOAT_D to FREG_EXPR
		gen move %1, %2.reg

	from FLOAT_W to FSREG_EXPR
		gen move %1, %2.reg


TESTS

	/* Given "mrX %1, %1", ncgg would say, "Instruction destroys
	 * %1, not allowed here".  We use mrX_readonly to trick ncgg.
	 */
	to test GPR
		gen
			mrX_readonly %1, %1


STACKINGRULES

	from SPFP+REG to STACK
		gen
			COMMENT("stack SPFP+REG")
			stwu %1, {IND_RC_W, sp, 0-4}

	from INT_W-SPFP-REG to STACK
		gen
			COMMENT("stack INT_W-SPFP-REG")
			move %1, RSCRATCH
			stwu RSCRATCH, {IND_RC_W, sp, 0-4}

	from FLOAT_D-FREG to STACK
		gen
			COMMENT("stack FLOAT_D-FREG")
			move %1, FSCRATCH
			stfdu FSCRATCH, {IND_RC_D, sp, 0-8}

	from FREG to STACK
		gen
			COMMENT("stack FREG")
			stfdu %1, {IND_RC_D, sp, 0-8}

	from FSREG to STACK
		gen
			COMMENT("stack FSREG")
			stfsu %1, {IND_RC_W, sp, 0-4}

	/*
	 * We never stack LOCAL or DLOCAL tokens, because we only use
	 * them for register variables, so ncg pushes the register,
	 * not the token.  These rules only prevent an error in ncgg.
	 */
	from LOCAL to STACK
		gen bug {LABEL, "STACKING LOCAL"}
	from DLOCAL to STACK
		gen bug {LABEL, "STACKING DLOCAL"}


COERCIONS

	/* The unstacking coercions emit many "addi sp, sp, X"
	 * instructions; the target optimizer (top) will merge them.
	 */

	from STACK
		uses REG
		gen
			COMMENT("coerce STACK->REG")
			lwz %a, {IND_RC_W, sp, 0}
			addi sp, sp, {C, 4}
		yields %a

	from STACK
		uses FREG
		gen
			COMMENT("coerce STACK->FREG")
			lfd %a, {IND_RC_D, sp, 0}
			addi sp, sp, {C, 8}
		yields %a

	from STACK
		uses FSREG
		gen
			COMMENT("coerce STACK->FSREG")
			lfs %a, {IND_RC_W, sp, 0}
			addi sp, sp, {C, 4}
		yields %a

	/* "uses REG=%1" may find and reuse a register containing the
	 * same token.  For contrast, "uses REG gen move %1, %a" would
	 * pick a different register before doing the move.
	 *
	 * "reusing %1" helps when coercing an INT_W token like
	 * {SUM_RC, r3, 0-4} to REG3, by not stacking the token.
	 */

	from INT_W
		uses reusing %1, REG=%1
		yields %a

	from FLOAT_D
		uses reusing %1, FREG=%1
		yields %a

	from FLOAT_W
		uses reusing %1, FSREG=%1
		yields %a

	/* Splitting coercions can't allocate registers.
	 * PowerPC can't add r0 + constant.  Use r12.
	 */

	from IND_RC_D %off<=0x7FFA
		yields
			{IND_RC_W, %1.reg, %1.off+4}
			{IND_RC_W, %1.reg, %1.off}

	from IND_RC_D
		/* Don't move to %1.reg; it might be a regvar. */
		gen move {SUM_RC, %1.reg, %1.off}, r12
		yields {IND_RC_W, r12, 4} {IND_RC_W, r12, 0}

	from IND_RR_D
		gen move {SUM_RR, %1.reg1, %1.reg2}, r12
		yields {IND_RC_W, r12, 4} {IND_RC_W, r12, 0}

	from FRAME_D %off<=0x7FFA
		yields
			{FRAME_W, %1.level, %1.reg, %1.off+4, 4}
			{FRAME_W, %1.level, %1.reg, %1.off, 4}


PATTERNS

/* Constants */

	pat loc $1==(0-0x8000)             /* Load constant */
		yields {CONST_N8000, $1}
	pat loc $1>=(0-0x7FFF) && $1<=(0-1)
		yields {CONST_N7FFF_N0001, $1}
	pat loc $1>=0 && $1<=0x7FFF
		yields {CONST_0000_7FFF, $1}
	pat loc $1==0x8000
		yields {CONST_8000, $1}
	pat loc $1>=0x8001 && $1<=0xFFFF
		yields {CONST_8001_FFFF, $1}
	pat loc lo($1)==0
		yields {CONST_HI_ZR, $1}
	pat loc
		yields {CONST_HI_LO, $1}


/* Stack shuffles */

	/* The peephole optimizer does:  loc $1 ass 4 -> asp $1
	 * To optimize multiplication, it uses:  dup 8 asp 4
	 */

	pat asp $1==4                      /* Adjust stack by constant */
		with exact INT_W+FLOAT_W
			/* drop %1 */
		with STACK
			gen addi sp, sp, {C, 4}
	pat asp smalls($1)
		with STACK
			gen addi sp, sp, {C, $1}
	pat asp lo($1)==0
		with STACK
			gen addi sp, sp, {C, hi($1)}
	pat asp
		with STACK
			gen
				addis sp, sp, {C, his($1)}
				addi sp, sp, {C, los($1)}

	pat ass $1==4                      /* Adjust stack by variable */
		with REG STACK
			gen add sp, sp, %1

	/* To duplicate a token, we coerce the token into a register,
	 * then duplicate the register.  This decreases code size.
	 */

	pat dup $1==4                      /* Duplicate word on top of stack */
		with REG+FSREG
			yields %1 %1

	pat dup $1==8                      /* Duplicate double-word */
		with REG+FSREG REG+FSREG
			yields %2 %1 %2 %1
		with FREG
			yields %1 %1

	pat dup                            /* Duplicate other size */
		leaving
			loc $1
			dus 4

	pat dus $1==4                      /* Duplicate variable size */
		with REG STACK
			/* ( a size%1 -- a a ) */
			uses REG, REG
			gen
				srwi %a, %1, {C, 2}
				mtspr ctr, %a
				add %b, sp, %1
			1:	lwzu %a, {IND_RC_W, %b, 0-4}
				stwu %a, {IND_RC_W, sp, 0-4}
				bdnz {LABEL, "1b"}

	pat exg $1==4                      /* Exchange top two words */
		with INT_W+FLOAT_W INT_W+FLOAT_W
			yields %1 %2

	pat exg defined($1)                /* Exchange other size */
		leaving
			loc $1
			cal ".exg"

	pat exg !defined($1)
		leaving
			cal ".exg"


/* Type conversions */

	pat loc loc ciu                    /* signed -> unsigned */
		leaving
			loc $1
			loc $2
			cuu

	pat loc loc cui                    /* unsigned -> signed */
		leaving
			loc $1
			loc $2
			cuu

	pat loc loc cuu $1<=4 && $2<=4     /* unsigned -> unsigned */
		/* nop */

	pat loc loc cii $1<=4 && $2<=$1
		/* signed -> signed of smaller or same size,
		 * no sign extension */

	pat loc loc cii $1==1 && $2<=4     /* sign-extend char */
		with REG
			yields {SEX_B, %1}

	pat loc loc cii $1==2 && $2<=4     /* sign-extend short */
		with REG
			yields {SEX_H, %1}


/* Local variables */

	pat lal smalls($1)                 /* Load address of local */
		yields {SUM_RC, fp, $1}

	pat lal                            /* Load address of local */
		uses REG={SUM_RIS, fp, his($1)}
		yields {SUM_RC, %a, los($1)}

	pat lal loi smalls($1) && $2==1    /* Load byte from local */
		yields {FRAME_B, 0, fp, $1, 1}

	/* Load half-word from local and sign-extend */
	pat lal loi loc loc cii smalls($1) && $2==2 && $3==2 && $4==4
		yields {FRAME_H_S, 0, fp, $1, 1}

	pat lal loi smalls($1) && $2==2    /* Load half-word from local */
		yields {FRAME_H, 0, fp, $1, 1}

	/* Load word from local */
	pat lol inreg($1)==reg_any || inreg($1)==reg_float
		yields {LOCAL, $1}
	pat lol smalls($1)
		yields {FRAME_W, 0, fp, $1, 4}
	pat lol
		leaving
			lal $1
			loi 4

	pat ldl inreg($1)==reg_float       /* Load double-word from local */
		yields {DLOCAL, $1}
	pat ldl smalls($1) && smalls($1+4)
		/* smalls($1+4) implies FRAME_D %off<=0xFFFA */
		yields {FRAME_D, 0, fp, $1, 8}
	pat ldl
		leaving
			lal $1
			loi 8

	pat lal sti smalls($1) && $2==1    /* Store byte to local */
		with REG
			kills IND_V, FRAME_V %level==0 && fover($1, 1)
			gen move %1, {FRAME_B, 0, fp, $1, 1}

	pat lal sti smalls($1) && $2==2    /* Store half-word to local */
		with REG
			kills IND_V, FRAME_V %level==0 && fover($1, 2)
			gen move %1, {FRAME_H, 0, fp, $1, 2}

	pat stl inreg($1)==reg_any         /* Store word to local */
		with exact INT_W
			/* ncg fails to infer that regvar($1) is dead! */
			kills regvar($1)
			gen move %1, {REG_EXPR, regvar($1)}
		with STACK
			gen
				lwz {LOCAL, $1}, {IND_RC_W, sp, 0}
				addi sp, sp, {C, 4}
	pat stl inreg($1)==reg_float
		with exact FLOAT_W
			kills regvar_w($1, reg_float)
			gen move %1, {FSREG_EXPR, regvar_w($1, reg_float)}
		with STACK
			gen
				lfs {LOCAL, $1}, {IND_RC_W, sp, 0}
				addi sp, sp, {C, 4}
	pat stl smalls($1)
		with REG+FSREG
			kills IND_V, FRAME_V %level==0 && fover($1, 4)
			gen move %1, {FRAME_W, 0, fp, $1, 4}
	pat stl
		leaving
			lal $1
			sti 4

	pat sdl inreg($1)==reg_float       /* Store double-word to local */
		with exact FLOAT_D
			kills regvar_d($1, reg_float)
			gen move %1, {FREG_EXPR, regvar_d($1, reg_float)}
		with STACK
			gen
				lfd {DLOCAL, $1}, {IND_RC_D, sp, 0}
				addi sp, sp, {C, 8}
	pat sdl smalls($1) && smalls($1+4)
		with REG REG
			kills IND_V, FRAME_V %level==0 && fover($1, 8)
			gen
				move %1, {FRAME_W, 0, fp, $1, 4}
				move %2, {FRAME_W, 0, fp, $1+4, 4}
		with FREG
			kills IND_V, FRAME_V %level==0 && fover($1, 4)
			gen move %1, {FRAME_D, 0, fp, $1, 8}
	pat sdl
		leaving
			lal $1
			sti 8

	pat lil                            /* Load indirect from local */
		leaving
			lol $1
			loi 4

	pat sil                            /* Store indirect to local */
		leaving
			lol $1
			sti 4

	pat zrl                            /* Zero local */
		leaving
			loc 0
			stl $1

	pat inl                            /* Increment local */
		leaving
			lol $1
			loc 1
			adi 4
			stl $1

	pat del                            /* Decrement local */
		leaving
			lol $1
			loc 1
			sbi 4
			stl $1


/* Local variables of procedures on static chain */

	/* lxa (lexical argument base) -> lxl (lexical local base) */
	pat lxa adp nicelx($1)
		leaving lxl $1 adp $2+EM_BSIZE
	pat lxa lof nicelx($1)
		leaving lxl $1 lof $2+EM_BSIZE
	pat lxa ldf nicelx($1)
		leaving lxl $1 ldf $2+EM_BSIZE
	pat lxa stf nicelx($1)
		leaving lxl $1 stf $2+EM_BSIZE
	pat lxa sdf nicelx($1)
		leaving lxl $1 stf $2+EM_BSIZE
	pat lxa nicelx($1)
		leaving lxl $1 adp EM_BSIZE

	/* Load locals in statically enclosing procedures */
	pat lxl adp loi nicelx($1) && smalls($2) && $3==1
		uses REG={LXFRAME, $1}
		yields {FRAME_B, $1, %a, $2, 1}
	pat lxl adp loi loc loc cii nicelx($1) && smalls($2) &&
	                            $3==2 && $4==2 && $5==4
		uses REG={LXFRAME, $1}
		yields {FRAME_H_S, $1, %a, $2, 2}
	pat lxl adp loi nicelx($1) && smalls($2) && $3==2
		uses REG={LXFRAME, $1}
		yields {FRAME_H, $1, %a, $2, 2}
	pat lxl lof nicelx($1) && smalls($2)
		uses REG={LXFRAME, $1}
		yields {FRAME_W, $1, %a, $2, 4}
	pat lxl ldf nicelx($1) && smalls($2) && smalls($2+4)
		uses REG={LXFRAME, $1}
		/* smalls($2+4) implies FRAME_D %off<=0xFFFA */
		yields {FRAME_D, $1, %a, $2, 8}

	/* Store locals in statically enclosing procedures */
	pat lxl adp sti nicelx($1) && smalls($2) && $3==1
		with REG
			kills IND_V, FRAME_V %level==$1 && fover($2, 1)
			uses REG={LXFRAME, $1}
			gen move %1, {FRAME_B, $1, %a, $2, 1}
	pat lxl adp sti nicelx($1) && smalls($2) && $3==2
		with REG
			kills IND_V, FRAME_V %level==$1 && fover($2, 2)
			uses REG={LXFRAME, $1}
			gen move %1, {FRAME_H, $1, %a, $2, 2}
	pat lxl stf nicelx($1) && smalls($2)
		with REG+FSREG
			kills IND_V, FRAME_V %level==$1 && fover($2, 4)
			uses REG={LXFRAME, $1}
			gen move %1, {FRAME_W, $1, %a, $2, 4}
	pat lxl sdf nicelx($1) && smalls($2) && smalls($2+4)
		with REG REG
			kills IND_V, FRAME_V %level==$1 && fover($2, 8)
			uses REG={LXFRAME, $1}
			gen
				move %1, {FRAME_W, $1, %a, $2, 4}
				move %2, {FRAME_W, $1, %a, $2+4, 4}
		with FREG
			kills IND_V, FRAME_V %level==$1 && fover($2, 8)
			uses REG={LXFRAME, $1}
			gen move %1, {FRAME_D, $1, %a, $2, 8}

	pat lxl nicelx($1)                 /* Local base on static chain */
		uses REG={LXFRAME, $1}
		yields %a  /* Can't yield LXFRAME. */
	pat lxl stl nicelx($1) && inreg($2)==reg_any
		kills regvar($2)
		gen move {LXFRAME, $1}, {REG_EXPR, regvar($2)}

	pat lxl $1==0                      /* Our local base */
		yields fp

	pat lxa $1==0                      /* Our argument base */
		yields {SUM_RC, fp, EM_BSIZE}


/* Global variables */

	pat lpi                            /* Load address of function */
		leaving
			lae $1

	pat lae                            /* Load address of external */
		uses REG={LABEL_HA, $1}
		yields {SUM_RL, %a, $1}

	pat loe                            /* Load word external */
		leaving
			lae $1
			loi 4

	pat ste                            /* Store word external */
		leaving
			lae $1
			sti 4

	pat lde                            /* Load double-word external */
		leaving
			lae $1
			loi 8

	pat sde                            /* Store double-word external */
		leaving
			lae $1
			sti 8

	pat zre                            /* Zero external */
		leaving
			loc 0
			ste $1

	pat ine                            /* Increment external */
		leaving
			loe $1
			inc
			ste $1

	pat dee                            /* Decrement external */
		leaving
			loe $1
			dec
			ste $1


/* Structures */

	pat lof                            /* Load word offsetted */
		leaving
			adp $1
			loi 4

	pat ldf                            /* Load double-word offsetted */
		leaving
			adp $1
			loi 8

	pat stf                            /* Store word offsetted */
		leaving
			adp $1
			sti 4

	pat sdf                            /* Store double-word offsetted */
		leaving
			adp $1
			sti 8


/* Loads and stores */

	pat loi $1==1                      /* Load byte indirect */
		with REG
			yields {IND_RC_B, %1, 0}
		with exact SUM_RC
			yields {IND_RC_B, %1.reg, %1.off}
		with exact SUM_RL
			yields {IND_RL_B, %1.reg, %1.adr}
		with exact SUM_RR
			yields {IND_RR_B, %1.reg1, %1.reg2}

	/* Load half-word indirect and sign-extend */
	pat loi loc loc cii $1==2 && $2==2 && $3==4
		with REG
			yields {IND_RC_H_S, %1, 0}
		with exact SUM_RC
			yields {IND_RC_H_S, %1.reg, %1.off}
		with exact SUM_RL
			yields {IND_RL_H_S, %1.reg, %1.adr}
		with exact SUM_RR
			yields {IND_RR_H_S, %1.reg1, %1.reg2}

	pat loi $1==2                      /* Load half-word indirect */
		with REG
			yields {IND_RC_H, %1, 0}
		with exact SUM_RC
			yields {IND_RC_H, %1.reg, %1.off}
		with exact SUM_RL
			yields {IND_RL_H, %1.reg, %1.adr}
		with exact SUM_RR
			yields {IND_RR_H, %1.reg1, %1.reg2}

	pat loi $1==4                      /* Load word indirect */
		with REG
			yields {IND_RC_W, %1, 0}
		with exact SUM_RC
			yields {IND_RC_W, %1.reg, %1.off}
		with exact SUM_RL
			yields {IND_RL_W, %1.reg, %1.adr}
		with exact SUM_RR
			yields {IND_RR_W, %1.reg1, %1.reg2}

	pat loi $1==8                      /* Load double-word indirect */
		with REG
			yields {IND_RC_D, %1, 0}
		with exact SUM_RC
			yields {IND_RC_D, %1.reg, %1.off}
		with exact SUM_RL
			yields {IND_RL_D, %1.reg, %1.adr}
		with exact SUM_RR
			yields {IND_RR_D, %1.reg1, %1.reg2}

	pat loi                            /* Load arbitrary size */
		leaving
			loc $1
			los 4

	pat los $1==4                      /* Load arbitrary size */
		with REG3 STACK
			kills ALL
			gen bl {LABEL, ".los4"}

	pat sti $1==1                      /* Store byte indirect */
		with REG REG
			kills MEMORY
			gen move %2, {IND_RC_B, %1, 0}
		with SUM_RC REG
			kills MEMORY
			gen move %2, {IND_RC_B, %1.reg, %1.off}
		with SUM_RL REG
			kills MEMORY
			gen move %2, {IND_RL_B, %1.reg, %1.adr}
		with SUM_RR REG
			kills MEMORY
			gen move %2, {IND_RR_B, %1.reg1, %1.reg2}

	pat sti $1==2                      /* Store half-word indirect */
		with REG REG
			kills MEMORY
			gen move %2, {IND_RC_H, %1, 0}
		with SUM_RC REG
			kills MEMORY
			gen move %2, {IND_RC_H, %1.reg, %1.off}
		with SUM_RL REG
			kills MEMORY
			gen move %2, {IND_RL_H, %1.reg, %1.adr}
		with SUM_RR REG
			kills MEMORY
			gen move %2, {IND_RR_H, %1.reg1, %1.reg2}

	pat sti $1==4                      /* Store word indirect */
		with REG REG+FSREG
			kills MEMORY
			gen move %2, {IND_RC_W, %1, 0}
		with SUM_RC REG+FSREG
			kills MEMORY
			gen move %2, {IND_RC_W, %1.reg, %1.off}
		with SUM_RL REG+FSREG
			kills MEMORY
			gen move %2, {IND_RL_W, %1.reg, %1.adr}
		with SUM_RR REG+FSREG
			kills MEMORY
			gen move %2, {IND_RR_W, %1.reg1, %1.reg2}

	pat sti $1==8                      /* Store double-word indirect */
		with REG FREG
			kills MEMORY
			gen move %2, {IND_RC_D, %1, 0}
		with SUM_RC FREG
			kills MEMORY
			gen move %2, {IND_RC_D, %1.reg, %1.off}
		with SUM_RL FREG
			kills MEMORY
			gen move %2, {IND_RL_D, %1.reg, %1.adr}
		with SUM_RR FREG
			kills MEMORY
			gen move %2, {IND_RR_D, %1.reg1, %1.reg2}
		with REG REG REG
			kills MEMORY
			gen
				move %2, {IND_RC_W, %1, 0}
				move %3, {IND_RC_W, %1, 4}

	pat sti                            /* Store arbitrary size */
		leaving
			loc $1
			sts 4

	pat sts $1==4                      /* Store arbitrary size */
		with REG3 STACK
			kills ALL
			gen bl {LABEL, ".sts4"}


/* Arithmetic wrappers */

	pat ads $1==4                      /* Add var to pointer */
		leaving adi $1

	pat sbs $1==4                      /* Subtract var from pointer */
		leaving sbi $1

	pat adp                            /* Add constant to pointer */
		leaving
			loc $1
			adi 4

	pat adu                            /* Add unsigned */
		leaving
			adi $1

	pat sbu                            /* Subtract unsigned */
		leaving
			sbi $1

	pat inc                            /* Add 1 */
		leaving
			loc 1
			adi 4

	pat dec                            /* Subtract 1 */
		leaving
			loc 1
			sbi 4

	pat mlu                            /* Multiply unsigned */
		leaving
			mli $1

	pat slu                            /* Shift left unsigned */
		leaving
			sli $1


/* Word arithmetic */

	/* Like most back ends, this one doesn't trap EIOVFL, so it
	 * ignores overflow in signed integers.
	 */

	pat adi $1==4                      /* Add word (second + top) */
		with REG REG
			yields {SUM_RR, %1, %2}
		with CONST2 REG
			yields {SUM_RC, %2, %1.val}
		with REG CONST2
			yields {SUM_RC, %1, %2.val}
		with CONST_HI_ZR REG
			yields {SUM_RIS, %2, his(%1.val)}
		with REG CONST_HI_ZR
			yields {SUM_RIS, %1, his(%2.val)}
		with CONST_STACK-CONST2-CONST_HI_ZR REG
			uses reusing %2, REG={SUM_RIS, %2, his(%1.val)}
			yields {SUM_RC, %a, los(%1.val)}
		with REG CONST_STACK-CONST2-CONST_HI_ZR
			uses reusing %1, REG={SUM_RIS, %1, his(%2.val)}
			yields {SUM_RC, %a, los(%2.val)}

	pat sbi $1==4                      /* Subtract word (second - top) */
		with REG REG
			uses reusing %1, reusing %2, REG
			yields {SUB_RR, %2, %1}
		with CONST2_WHEN_NEG REG
			yields {SUM_RC, %2, 0-%1.val}
		with REG CONST2
			yields {SUB_CR, %2.val, %1}
		with CONST_HI_ZR REG
			yields {SUM_RIS, %2, his(0-%1.val)}
		with CONST_STACK-CONST2_WHEN_NEG-CONST_HI_ZR REG
			uses reusing %2, REG={SUM_RIS, %2, his(0-%1.val)}
			yields {SUM_RC, %a, los(0-%1.val)}

	pat ngi $1==4                      /* Negate word */
		with REG
			yields {NEG_R, %1}

	pat mli $1==4                      /* Multiply word (second * top) */
		with CONST2 REG
			yields {MUL_RC, %2, %1.val}
		with REG CONST2
			yields {MUL_RC, %1, %2.val}
		with REG REG
			yields {MUL_RR, %2, %1}

	pat dvi $1==4                      /* Divide word (second / top) */
		with REG REG
			yields {DIV_RR, %2, %1}

	pat dvu $1==4             /* Divide unsigned word (second / top) */
		with REG REG
			yields {DIV_RR_U, %2, %1}

	/* To calculate a remainder:  a % b = a - (a / b * b) */

	pat rmi $1==4                      /* Remainder word (second % top) */
		with REG REG
			uses REG={DIV_RR, %2, %1}, REG
			gen move {MUL_RR, %a, %1}, %b
			yields {SUB_RR, %2, %b}

	pat rmu $1==4             /* Remainder unsigned word (second % top) */
		with REG REG
			uses REG={DIV_RR_U, %2, %1}, REG
			gen move {MUL_RR, %a, %1}, %b
			yields {SUB_RR, %2, %b}


/* Bitwise logic */

	/* This back end doesn't know how to combine shifts and
	 * bitwise ops to emit rlwinm, rlwnm, or rlwimi instructions.
	 */

	pat and $1==4                      /* AND word */
		with REG NOT_R
			yields {ANDC_RR, %1, %2.reg}
		with NOT_R REG
			yields {ANDC_RR, %2, %1.reg}
		with REG REG
			yields {AND_RR, %1, %2}
		with REG UCONST2
			yields {AND_RC, %1, %2.val}
		with UCONST2 REG
			yields {AND_RC, %2, %1.val}
		with REG CONST_HI_ZR
			yields {AND_RIS, %1, hi(%2.val)}
		with CONST_HI_ZR REG
			yields {AND_RIS, %2, hi(%1.val)}

	pat and defined($1)                /* AND set */
		leaving
			loc $1
			cal ".and"

	pat and !defined($1)
		leaving
			cal ".and"

	pat ior $1==4                      /* OR word */
		with REG NOT_R
			yields {ORC_RR, %1, %2.reg}
		with NOT_R REG
			yields {ORC_RR, %2, %1.reg}
		with REG REG
			yields {OR_RR, %1, %2}
		with REG UCONST2
			yields {OR_RC, %1, %2.val}
		with UCONST2 REG
			yields {OR_RC, %2, %1.val}
		with REG CONST_HI_ZR
			yields {OR_RIS, %1, hi(%2.val)}
		with CONST_HI_ZR REG
			yields {OR_RIS, %2, hi(%1.val)}
		with REG CONST_STACK-UCONST2-CONST_HI_ZR
			uses reusing %1, REG={OR_RIS, %1, hi(%2.val)}
			yields {OR_RC, %1, lo(%2.val)}
		with CONST_STACK-UCONST2-CONST_HI_ZR REG
			uses reusing %2, REG={OR_RIS, %2, hi(%1.val)}
			yields {OR_RC, %2, lo(%1.val)}

	pat ior defined($1)                /* OR set */
		leaving
			loc $1
			cal ".ior"

	/* OR set (variable), used in lang/m2/libm2/LtoUset.e */
	pat ior !defined($1)
		leaving
			cal ".ior"

	pat xor $1==4                      /* XOR word */
		with REG REG
			yields {XOR_RR, %1, %2}
		with REG UCONST2
			yields {XOR_RC, %1, %2.val}
		with UCONST2 REG
			yields {XOR_RC, %2, %1.val}
		with REG CONST_HI_ZR
			yields {XOR_RIS, %1, hi(%2.val)}
		with CONST_HI_ZR REG
			yields {XOR_RIS, %2, hi(%1.val)}
		with REG CONST_STACK-UCONST2-CONST_HI_ZR
			uses reusing %1, REG={XOR_RIS, %1, hi(%2.val)}
			yields {XOR_RC, %1, lo(%2.val)}
		with CONST_STACK-UCONST2-CONST_HI_ZR REG
			uses reusing %2, REG={XOR_RIS, %2, hi(%1.val)}
			yields {XOR_RC, %2, lo(%1.val)}

	pat xor defined($1)                /* XOR set */
		leaving
			loc $1
			cal ".xor"

	pat xor !defined($1)
		leaving
			cal ".xor"

	pat com $1==4                      /* NOT word */
		with exact AND_RR
			yields {NAND_RR, %1.reg1, %1.reg2}
		with exact OR_RR
			yields {NOR_RR, %1.reg1, %1.reg2}
		with exact XOR_RR
			yields {EQV_RR, %1.reg1, %1.reg2}
		with REG
			yields {NOT_R, %1}

	pat com defined($1)                /* NOT set */
		leaving
			loc $1
			cal ".com"

	pat com !defined($1)
		leaving
			cal ".com"

	pat zer $1==4                      /* Push zero */
		leaving
			loc 0

	pat zer defined($1)                /* Create empty set */
		leaving
			loc $1
			cal ".zer"


/* Shifts and rotations */

	pat sli $1==4                      /* Shift left (second << top) */
		with CONST_STACK REG
			uses reusing %2, REG
			gen slwi %a, %2, {C, %1.val & 0x1F}
			yields %a
		with REG REG
			uses reusing %1, reusing %2, REG
			gen slw %a, %2, %1
			yields %a
	pat sli stl $1==4 && inreg($2)==reg_any
		with CONST_STACK REG
			gen slwi {LOCAL, $2}, %2, {C, %1.val & 0x1F}
		with REG REG
			gen slw {LOCAL, $2}, %2, %1

	pat sri $1==4               /* Shift right signed (second >> top) */
		with CONST_STACK REG
			uses reusing %2, REG
			gen srawi %a, %2, {C, %1.val & 0x1F}
			yields %a
		with REG REG
			uses reusing %1, reusing %2, REG
			gen sraw %a, %2, %1
			yields %a
	pat sri stl $1==4 && inreg($2)==reg_any
		with CONST_STACK REG
			gen srawi {LOCAL, $2}, %2, {C, %1.val & 0x1F}
		with REG REG
			gen sraw {LOCAL, $2}, %2, %1

	pat sru $1==4               /* Shift right unsigned (second >> top) */
		with CONST_STACK REG
			uses reusing %2, REG
			gen srwi %a, %2, {C, %1.val & 0x1F}
			yields %a
		with REG REG
			uses reusing %1, reusing %2, REG
			gen srw %a, %2, %1
			yields %a
	pat sru stl $1==4 && inreg($2)==reg_any
		with CONST_STACK REG
			gen srwi {LOCAL, $2}, %2, {C, %1.val & 0x1F}
		with REG REG
			gen srw {LOCAL, $2}, %2, %1

	pat rol $1==4                      /* Rotate left word */
		with CONST_STACK REG
			uses reusing %2, REG
			gen rotlwi %a, %2, {C, %1.val & 0x1F}
			yields %a
		with REG REG
			uses reusing %1, reusing %2, REG
			gen rotlw %a, %2, %1
			yields %a
	pat rol stl $1==4 && inreg($2)==reg_any
		with CONST_STACK REG
			gen rotlwi {LOCAL, $2}, %2, {C, %1.val & 0x1F}
		with REG REG
			gen rotlw {LOCAL, $2}, %2, %1

	/*
	 * ror 4 -> ngi 4, rol 4
	 *   because to rotate right by n bits is to rotate left by
	 *   (32 - n), which is to rotate left by -n.  PowerPC rotlw
	 *   handles -n as (-n & 0x1F).
	 */

	pat ror $1==4                      /* Rotate right word */
		with CONST_STACK REG
			uses reusing %2, REG
			gen rotrwi %a, %2, {C, %1.val & 0x1F}
			yields %a
		with /* anything */
			leaving
				ngi 4
				rol 4
	pat ror stl $1==4 && inreg($2)==reg_any
		with CONST_STACK REG
			gen rotrwi {LOCAL, $2}, %2, {C, %1.val & 0x1F}
		with /* anything */
			leaving
				ngi 4
				rol 4
				stl $2


/* Arrays */

	pat aar $1==4                      /* Address of array element */
		leaving cal ".aar4"

	pat lar $1==4                      /* Load from array */
		with STACK
			kills ALL
			gen
				bl {LABEL, ".aar4"}
				/* pass r3 = size from .aar4 to .los4 */
				bl {LABEL, ".los4"}

	pat lae lar $2==4 && nicesize(rom($1, 3))
		leaving
			lae $1
			aar 4
			loi rom($1, 3)

	pat sar $1==4                      /* Store to array */
		with STACK
			kills ALL
			gen
				bl {LABEL, ".aar4"}
				/* pass r3 = size from .aar4 to .sts4 */
				bl {LABEL, ".sts4"}

	pat lae sar $2==4 && nicesize(rom($1, 3))
		leaving
			lae $1
			aar 4
			sti rom($1, 3)


/* Sets */

	pat set defined($1)                /* Create singleton set */
		leaving
			loc $1
			cal ".set"

	/* Create set (variable), used in lang/m2/libm2/LtoUset.e */
	pat set !defined($1)
		leaving
			cal ".set"

	pat inn defined($1)                /* Test for set bit */
		leaving
			loc $1
			cal ".inn"

	pat inn !defined($1)
		leaving
			cal ".inn"


/* Boolean resolutions */

	pat teq                            /* top = (top == 0) */
		with REG
			uses reusing %1, REG
			gen
				test %1
				mfcr %a
			yields {XEQ, %a}

	pat tne                            /* top = (top != 0) */
		with REG
			uses reusing %1, REG
			gen
				test %1
				mfcr %a
			yields {XNE, %a}

	pat tlt                            /* top = (top < 0) */
		with REG
			uses reusing %1, REG
			gen
				test %1
				mfcr %a
			yields {XLT, %a}

	pat tle                            /* top = (top <= 0) */
		with REG
			uses reusing %1, REG
			gen
				test %1
				mfcr %a
			yields {XLE, %a}

	pat tgt                            /* top = (top > 0) */
		with REG
			uses reusing %1, REG
			gen
				test %1
				mfcr %a
			yields {XGT, %a}

	pat tge                            /* top = (top >= 0) */
		with REG
			uses reusing %1, REG
			gen
				test %1
				mfcr %a
			yields {XGE, %a}

	pat cmi teq $1==4                  /* Signed second == top */
		with REG CONST2
			uses reusing %1, REG={COND_RC, %1, %2.val}
			yields {XEQ, %a}
		with CONST2 REG
			uses reusing %2, REG={COND_RC, %2, %1.val}
			yields {XEQ, %a}
		with REG REG
			uses reusing %1, reusing %2, REG={COND_RR, %2, %1}
			yields {XEQ, %a}

	pat cmi tne $1==4                  /* Signed second != top */
		with REG CONST2
			uses reusing %1, REG={COND_RC, %1, %2.val}
			yields {XNE, %a}
		with CONST2 REG
			uses reusing %2, REG={COND_RC, %2, %1.val}
			yields {XNE, %a}
		with REG REG
			uses reusing %1, reusing %2, REG={COND_RR, %2, %1}
			yields {XNE, %a}

	pat cmi tgt $1==4                  /* Signed second > top */
		with REG CONST2
			uses reusing %1, REG={COND_RC, %1, %2.val}
			yields {XLT, %a}
		with CONST2 REG
			uses reusing %2, REG={COND_RC, %2, %1.val}
			yields {XGT, %a}
		with REG REG
			uses reusing %1, reusing %2, REG={COND_RR, %2, %1}
			yields {XGT, %a}

	pat cmi tge $1==4                  /* Signed second >= top */
		with REG CONST2
			uses reusing %1, REG={COND_RC, %1, %2.val}
			yields {XLE, %a}
		with CONST2 REG
			uses reusing %2, REG={COND_RC, %2, %1.val}
			yields {XGE, %a}
		with REG REG
			uses reusing %1, reusing %2, REG={COND_RR, %2, %1}
			yields {XGE, %a}

	pat cmi tlt $1==4                  /* Signed second < top */
		with REG CONST2
			uses reusing %1, REG={COND_RC, %1, %2.val}
			yields {XGT, %a}
		with CONST2 REG
			uses reusing %2, REG={COND_RC, %2, %1.val}
			yields {XLT, %a}
		with REG REG
			uses reusing %1, reusing %2, REG={COND_RR, %2, %1}
			yields {XLT, %a}

	pat cmi tle $1==4                  /* Signed second <= top */
		with REG CONST2
			uses reusing %1, REG={COND_RC, %1, %2.val}
			yields {XGE, %a}
		with CONST2 REG
			uses reusing %2, REG={COND_RC, %2, %1.val}
			yields {XLE, %a}
		with REG REG
			uses reusing %1, reusing %2, REG={COND_RR, %2, %1}
			yields {XLE, %a}

	pat cmu teq $1==4                  /* Unsigned second == top */
		with REG UCONST2
			uses reusing %1, REG={CONDL_RC, %1, %2.val}
			yields {XEQ, %a}
		with UCONST2 REG
			uses reusing %2, REG={CONDL_RC, %2, %1.val}
			yields {XEQ, %a}
		with REG REG
			uses reusing %1, reusing %2, REG={CONDL_RR, %2, %1}
			yields {XEQ, %a}

	pat cmu tne $1==4                  /* Unsigned second != top */
		with REG UCONST2
			uses reusing %1, REG={CONDL_RC, %1, %2.val}
			yields {XNE, %a}
		with UCONST2 REG
			uses reusing %2, REG={CONDL_RC, %2, %1.val}
			yields {XNE, %a}
		with REG REG
			uses reusing %1, reusing %2, REG={CONDL_RR, %2, %1}
			yields {XNE, %a}

	pat cmu tgt $1==4                  /* Unsigned second > top */
		with REG UCONST2
			uses reusing %1, REG={CONDL_RC, %1, %2.val}
			yields {XLT, %a}
		with UCONST2 REG
			uses reusing %2, REG={CONDL_RC, %2, %1.val}
			yields {XGT, %a}
		with REG REG
			uses reusing %1, reusing %2, REG={CONDL_RR, %2, %1}
			yields {XGT, %a}

	pat cmu tge $1==4                  /* Unsigned second >= top */
		with REG UCONST2
			uses reusing %1, REG={CONDL_RC, %1, %2.val}
			yields {XLE, %a}
		with UCONST2 REG
			uses reusing %2, REG={CONDL_RC, %2, %1.val}
			yields {XGE, %a}
		with REG REG
			uses reusing %1, reusing %2, REG={CONDL_RR, %2, %1}
			yields {XGE, %a}

	pat cmu tlt $1==4                  /* Unsigned second < top */
		with REG UCONST2
			uses reusing %1, REG={CONDL_RC, %1, %2.val}
			yields {XGT, %a}
		with UCONST2 REG
			uses reusing %2, REG={CONDL_RC, %2, %1.val}
			yields {XLT, %a}
		with REG REG
			uses reusing %1, reusing %2, REG={CONDL_RR, %2, %1}
			yields {XLT, %a}

	pat cmu tle $1==4                  /* Unsigned second <= top */
		with REG UCONST2
			uses reusing %1, REG={CONDL_RC, %1, %2.val}
			yields {XGE, %a}
		with UCONST2 REG
			uses reusing %2, REG={CONDL_RC, %2, %1.val}
			yields {XLE, %a}
		with REG REG
			uses reusing %1, reusing %2, REG={CONDL_RR, %2, %1}
			yields {XLE, %a}


/* Simple branches */

	proc zxx example zeq
		with REG STACK
			gen
				test %1
				bxx* {LABEL, $1}

	/* Pop signed int, branch if... */
	pat zeq    call zxx("beq")         /* top == 0 */
	pat zne    call zxx("bne")         /* top != 0 */
	pat zgt    call zxx("bgt")         /* top > 0 */
	pat zge    call zxx("bge")         /* top >= 0 */
	pat zlt    call zxx("blt")         /* top < 0 */
	pat zle    call zxx("ble")         /* top >= 0 */

	/* The peephole optimizer rewrites
	 *   cmi 4 zeq
	 * as beq, and does same for bne, bgt, and so on.
	 */

	proc bxx example beq
		with REG CONST2 STACK
			gen
				cmpwi %1, %2
				bxx[2] {LABEL, $1}
		with CONST2 REG STACK
			gen
				cmpwi %2, %1
				bxx[1] {LABEL, $1}
		with REG REG STACK
			gen
				cmpw %2, %1
				bxx[1] {LABEL, $1}

	/* Pop two signed ints, branch if... */
	pat beq    call bxx("beq", "beq")  /* second == top */
	pat bne    call bxx("bne", "bne")  /* second != top */
	pat bgt    call bxx("bgt", "blt")  /* second > top */
	pat bge    call bxx("bge", "ble")  /* second >= top */
	pat blt    call bxx("blt", "bgt")  /* second < top */
	pat ble    call bxx("ble", "bge")  /* second >= top */

	proc cmu4zxx example cmu zeq
		with REG CONST2 STACK
			gen
				cmplwi %1, %2
				bxx[2] {LABEL, $2}
		with CONST2 REG STACK
			gen
				cmplwi %2, %1
				bxx[1] {LABEL, $2}
		with REG REG STACK
			gen
				cmplw %2, %1
				bxx[1] {LABEL, $2}

	/* Pop two unsigned ints, branch if... */
	pat cmu zeq $1==4    call cmu4zxx("beq", "beq")
	pat cmu zne $1==4    call cmu4zxx("bne", "bne")
	pat cmu zgt $1==4    call cmu4zxx("bgt", "blt")
	pat cmu zge $1==4    call cmu4zxx("bge", "ble")
	pat cmu zlt $1==4    call cmu4zxx("blt", "bgt")
	pat cmu zle $1==4    call cmu4zxx("ble", "bge")


/* Comparisons */

	/* Each comparison extracts the lt and gt bits from cr0.
	 *   extlwi %a, %a, 2, 0
	 * puts lt in the sign bit, so lt yields a negative result,
	 * gt yields positive.
	 *   rlwinm %a, %a, 1, 31, 0
	 * puts gt in the sign bit, to reverse the comparison.
	 */

	pat cmi $1==4                      /* Signed tristate compare */
		with REG CONST2
			uses reusing %1, REG={COND_RC, %1, %2.val}
			gen rlwinm %a, %a, {C, 1}, {C, 31}, {C, 0}
			yields %a
		with CONST2 REG
			uses reusing %2, REG={COND_RC, %2, %1.val}
			gen extlwi %a, %a, {C, 2}, {C, 0}
			yields %a
		with REG REG
			uses reusing %1, reusing %2, REG={COND_RR, %2, %1}
			gen extlwi %a, %a, {C, 2}, {C, 0}
			yields %a

	pat cmu $1==4                      /* Unsigned tristate compare */
		with REG UCONST2
			uses reusing %1, REG={CONDL_RC, %1, %2.val}
			gen rlwinm %a, %a, {C, 1}, {C, 31}, {C, 0}
			yields %a
		with UCONST2 REG
			uses reusing %2, REG={CONDL_RC, %2, %1.val}
			gen extlwi %a, %a, {C, 2}, {C, 0}
			yields %a
		with REG REG
			uses reusing %1, reusing %2, REG={CONDL_RR, %2, %1}
			gen extlwi %a, %a, {C, 2}, {C, 0}
			yields %a

	pat cmp                            /* Compare pointers */
		leaving
			cmu 4

	pat cms $1==4                      /* Compare blocks (word sized) */
		leaving
			cmi 4

	pat cms defined($1)
		leaving
			loc $1
			cal ".cms"

	pat cms !defined($1)
		leaving
			cal ".cms"


/* Other branching and labelling */

	/* During an unconditional jump, if the top element on the
	 * stack has 4 bytes, then we hold it in register r3.
	 */
	pat lab topeltsize($1)==4 && !fallthrough($1)
		kills ALL
		gen labeldef $1
		yields r3

	pat lab topeltsize($1)==4 && fallthrough($1)
		with REG3 STACK
			kills ALL
			gen labeldef $1
			yields r3

	pat lab topeltsize($1)!=4          /* Label without r3 */
		with STACK
			kills ALL
			gen labeldef $1

	pat bra topeltsize($1)==4          /* Branch with r3 */
		with REG3 STACK
			gen b {LABEL, $1}

	pat bra topeltsize($1)!=4          /* Branch without r3 */
		with STACK
			gen b {LABEL, $1}


/* Miscellaneous */

	pat cal                            /* Call procedure */
		with STACK
			kills ALL
			gen bl {LABEL, $1}

	pat cai                            /* Call procedure indirect */
		with REG STACK
			kills ALL
			gen
				mtspr ctr, %1
				bctrl.

	pat lfr $1==4                      /* Load function result, word */
		yields r3

	pat lfr $1==8               /* Load function result, double-word */
		yields r4 r3

	pat ret $1==0                      /* Return from procedure */
		gen
			/* Restore saved registers. */
			return
			/* Epilog: restore lr and fp. */
			lwz r0, {IND_RC_W, fp, 4}
			mtspr lr, r0
			lwz r0, {IND_RC_W, fp, 0}
			/* Free our stack frame. */
			addi sp, fp, {C, 8}
			mr fp, r0
			blr.

	/* If "ret" coerces STACK to REG3, then top will delete the
	 * extra "addi sp, sp, 4".
	 */

	pat ret $1==4                      /* Return from procedure, word */
		with REG3
			leaving ret 0

	pat ret $1==8                      /* Return from proc, double-word */
		with REG3 INT_W
			gen move %2, r4
			leaving ret 0
		with REG3 STACK
			gen lwz r4, {IND_RC_W, sp, 0}
			leaving ret 0

	/*
	 * These rules for blm/bls are wrong if length is zero.
	 * So are several procedures in libem.
	 */

	pat blm                            /* Block move constant length */
		leaving
			loc $1
			bls

	pat bls                            /* Block move variable length */
		with REG SPFP+REG SPFP+REG
			/* allows sp as %2, %3 */
			/* ( src%3 dst%2 len%1 -- ) */
			uses reusing %1, REG, REG, REG
			gen
				srwi %a, %1, {C, 2}
				mtspr ctr, %a
				addi %b, %3, {C, 0-4}
				addi %c, %2, {C, 0-4}
			1:	lwzu %a, {IND_RC_W, %b, 4}
				stwu %a, {IND_RC_W, %c, 4}
				bdnz {LABEL, "1b"}

	pat csa                            /* Array-lookup switch */
		with STACK
			kills ALL
			gen b {LABEL, ".csa"}

	pat csb                            /* Table-lookup switch */
		with STACK
			kills ALL
			gen b {LABEL, ".csb"}


/* EM specials */

	pat fil                            /* Set current filename */
		leaving
			lae $1
			ste "hol0+4"

	pat lin                            /* Set current line number */
		leaving
			loc $1
			ste "hol0"

	pat lni                            /* Increment line number */
		leaving ine "hol0"

	pat lim                            /* Load EM trap ignore mask */
		leaving loe ".ignmask"

	pat sim                            /* Store EM trap ignore mask */
		leaving ste ".ignmask"

	pat sig                            /* Set trap handler, yield old */
		leaving
			loe ".trppc"
			exg 4
			ste ".trppc"

	pat trp                            /* Raise EM trap */
		with REG3
			kills ALL
			gen bl {LABEL, ".trp"}

	pat rtt                            /* Return from trap */
		leaving ret 0

	pat rck $1==4                      /* Range check */
		leaving cal ".rck"

	/* Our caller's local base, "lxl 0 dch", appears in
	 * lang/cem/libcc.ansi/setjmp/setjmp.e, lang/m2/libm2/par_misc.e
	 */
	pat lxl dch $1==0
		yields {IND_RC_W, fp, FP_OFFSET}

	pat dch               /* Dynamic chain: LB -> caller's LB */
		with REG
			yields {IND_RC_W, %1, FP_OFFSET}

	pat lpb                            /* LB -> argument base */
		leaving adp EM_BSIZE

	/* "gto" must preserve the function result for "lfr", so
	 * longjmp() can pass the return value to setjmp().
	 *  - See lang/cem/libcc.ansi/setjmp/setjmp.e
	 *
	 * Must preserve r3 and r4, so no "uses REG".
	 * PowerPC can't add r0 + constant.  Use r12.
	 */
	pat gto                            /* longjmp */
		with STACK
			gen
				move {LABEL, $1}, r12
				move {IND_RC_W, r12, 8}, fp
				move {IND_RC_W, r12, 4}, sp
				move {IND_RC_W, r12, 0}, r12
				mtspr ctr, r12
				bctr.

	pat lor $1==0                      /* Load local base */
		leaving lxl 0

	pat lor $1==1                      /* Load stack pointer */
		with STACK
			yields sp

	/* Next few patterns for "lor 1" appear in
	 * lang/m2/libm2/par_misc.e
	 */
	pat lor adp $1==1 && smalls($2)    /* sp + constant */
		with STACK
			yields {SUM_RC, sp, $2}

	/* Subtract stack pointer by doing %1 - (sp - 4)
	 * because sp - 4 would point to %1.
	 */
	pat lor sbs loc adu $1==1 && $2==4 && $4==4
		with REG STACK
			uses reusing %1, REG
			gen subf %a, sp, %1
			yields %a
			leaving loc $3+4 adu 4
	pat lor sbs $1==1 && $2==4
		with REG STACK
			uses reusing %1, REG
			gen subf %a, sp, %1
			yields {SUM_RC, %a, 4}

	pat str $1==0                      /* Store local base */
		with INT_W
			gen move %1, fp
		with STACK
			gen
				lwz fp, {IND_RC_W, sp, 0}
				addi sp, sp, {C, 4}

	pat str $1==1                      /* Store stack pointer */
		with INT_W
			kills ALL
			gen move %1, sp
		with STACK
			kills ALL
			gen lwz sp, {IND_RC_W, sp, 0}


/* Single-precision floating-point */

	pat zrf $1==4                      /* Push zero */
		leaving loe ".fs_00000000"

	pat adf $1==4                      /* Add single */
		with FSREG FSREG
			uses reusing %1, reusing %2, FSREG
			gen fadds %a, %2, %1
			yields %a
	pat adf stl $1==4 && inreg($2)==reg_float
		with FSREG FSREG
			gen fadds {LOCAL, $2}, %2, %1

	pat sbf $1==4                      /* Subtract single */
		with FSREG FSREG
			uses reusing %1, reusing %2, FSREG
			gen fsubs %a, %2, %1
			yields %a
	pat sbf stl $1==4 && inreg($2)==reg_float
		with FSREG FSREG
			gen fsubs {LOCAL, $2}, %2, %1

	pat mlf $1==4                      /* Multiply single */
		with FSREG FSREG
			uses reusing %1, reusing %2, FSREG
			gen fmuls %a, %2, %1
			yields %a
	pat mlf stl $1==4 && inreg($2)==reg_float
		with FSREG FSREG
			gen fmuls {LOCAL, $2}, %2, %1

	pat dvf $1==4                      /* Divide single */
		with FSREG FSREG
			uses reusing %1, reusing %2, FSREG
			gen fdivs %a, %2, %1
			yields %a
	pat dvf stl $1==4 && inreg($2)==reg_float
		with FSREG FSREG
			gen fdivs {LOCAL, $2}, %2, %1

	pat ngf $1==4                      /* Negate single */
		with FSREG
			uses reusing %1, FSREG
			gen fneg %a, %1
			yields %a
	pat ngf stl $1==4 && inreg($2)==reg_float
		with FSREG
			gen fneg {LOCAL, $2}, %1

	/* When a or b is NaN, then a < b, a <= b, a > b, a >= b
	 * should all be false.  We can't make them false, because
	 *  - EM's _cmf_ is only for ordered comparisons.
	 *  - The peephole optimizer assumes (a < b) == !(a >= b).
	 *
	 * We do make a == b false and a != b true, by checking the
	 * eq (equal) bit or un (unordered) bit in cr0.
	 */

	pat cmf $1==4                      /* Compare single */
		with FSREG FSREG
			uses REG={COND_FS, %2, %1}
			/* Extract lt, gt, un; put lt in sign bit. */
			gen andisX %a, %a, {C, 0xd000}
			yields %a

	pat cmf teq $1==4                  /* Single second == top */
		with FSREG FSREG
			uses REG={COND_FS, %2, %1}
			yields {XEQ, %a}

	pat cmf tne $1==4                  /* Single second == top */
		with FSREG FSREG
			uses REG={COND_FS, %2, %1}
			yields {XNE, %a}

	pat cmf tgt $1==4                  /* Single second > top */
		with FSREG FSREG
			uses REG={COND_FS, %2, %1}
			yields {XGT, %a}

	pat cmf tge $1==4                  /* Single second >= top */
		with FSREG FSREG
			uses REG={COND_FS, %2, %1}
			yields {XGE, %a}

	pat cmf tlt $1==4                  /* Single second < top */
		with FSREG FSREG
			uses REG={COND_FS, %2, %1}
			yields {XLT, %a}

	pat cmf tle $1==4                  /* Single second <= top */
		with FSREG FSREG
			uses REG={COND_FS, %2, %1}
			yields {XLE, %a}

	proc cmf4zxx example cmf zeq
		with FSREG FSREG STACK
			gen
				fcmpo cr0, %2, %1
				bxx* {LABEL, $2}

	/* Pop 2 singles, branch if... */
	pat cmf zeq $1==4    call cmf4zxx("beq")
	pat cmf zne $1==4    call cmf4zxx("bne")
	pat cmf zgt $1==4    call cmf4zxx("bgt")
	pat cmf zge $1==4    call cmf4zxx("bge")
	pat cmf zlt $1==4    call cmf4zxx("blt")
	pat cmf zle $1==4    call cmf4zxx("ble")

	pat loc loc cff $1==4 && $2==8     /* Convert single to double */
		with FSREG
			yields %1.1

	pat loc loc cfi $1==4 && $2==4     /* Single to signed int */
		leaving
			loc 4
			loc 8
			cff
			loc 8
			loc 4
			cfi

	pat loc loc cfu $1==4 && $2==4     /* Single to unsigned int */
		leaving
			loc 4
			loc 8
			cff
			loc 8
			loc 4
			cfu

	pat loc loc cif $1==4 && $2==4     /* Signed int to single */
		leaving
			loc 4
			loc 8
			cif
			loc 8
			loc 4
			cff

	pat loc loc cuf $1==4 && $2==4     /* Unsigned int to single */
		leaving
			loc 4
			loc 8
			cuf
			loc 8
			loc 4
			cff

	pat fef $1==4                      /* Split fraction, exponent */
		leaving cal ".fef4"

	/* Multiply two singles, then split fraction, integer */
	pat fif $1==4
		leaving cal ".fif4"


/* Double-precision floating-point */

	pat zrf $1==8                      /* Push zero */
		leaving lde ".fd_00000000"

	pat adf $1==8                      /* Add double */
		with FREG FREG
			uses reusing %1, reusing %2, FREG
			gen fadd %a, %2, %1
			yields %a
	pat adf sdl $1==8 && inreg($2)==reg_float
		with FREG FREG
			gen fadd {DLOCAL, $2}, %2, %1

	pat sbf $1==8                      /* Subtract double */
		with FREG FREG
			uses reusing %1, reusing %2, FREG
			gen fsub %a, %2, %1
			yields %a
	pat sbf sdl $1==8 && inreg($2)==reg_float
		with FREG FREG
			gen fsub {DLOCAL, $2}, %2, %1

	pat mlf $1==8                      /* Multiply double */
		with FREG FREG
			uses reusing %1, reusing %2, FREG
			gen fmul %a, %2, %1
			yields %a
	pat mlf sdl $1==8 && inreg($2)==reg_float
		with FREG FREG
			gen fmul {DLOCAL, $2}, %2, %1

	pat dvf $1==8                      /* Divide double */
		with FREG FREG
			uses reusing %1, reusing %2, FREG
			gen fdiv %a, %2, %1
			yields %a
	pat dvf sdl $1==8 && inreg($2)==reg_float
		with FREG FREG
			gen fdiv {DLOCAL, $2}, %2, %1

	pat ngf $1==8                      /* Negate double */
		with FREG
			uses reusing %1, FREG
			gen fneg %a, %1
			yields %a
	pat ngf sdl $1==8 && inreg($2)==reg_float
		with FREG
			gen fneg {DLOCAL, $2}, %1

	/* To compare NaN, see comment above pat cmf $1==4 */

	pat cmf $1==8                      /* Compare double */
		with FREG FREG
			uses REG={COND_FD, %2, %1}
			/* Extract lt, gt, un; put lt in sign bit. */
			gen andisX %a, %a, {C, 0xd000}
			yields %a

	pat cmf teq $1==8                  /* Double second == top */
		with FREG FREG
			uses REG={COND_FD, %2, %1}
			yields {XEQ, %a}

	pat cmf tne $1==8                  /* Double second == top */
		with FREG FREG
			uses REG={COND_FD, %2, %1}
			yields {XNE, %a}

	pat cmf tgt $1==8                  /* Double second > top */
		with FREG FREG
			uses REG={COND_FD, %2, %1}
			yields {XGT, %a}

	pat cmf tge $1==8                  /* Double second >= top */
		with FREG FREG
			uses REG={COND_FD, %2, %1}
			yields {XGE, %a}

	pat cmf tlt $1==8                  /* Double second < top */
		with FREG FREG
			uses REG={COND_FD, %2, %1}
			yields {XLT, %a}

	pat cmf tle $1==8                  /* Double second <= top */
		with FREG FREG
			uses REG={COND_FD, %2, %1}
			yields {XLE, %a}

	proc cmf8zxx example cmf zeq
		with FREG FREG STACK
			gen
				fcmpo cr0, %2, %1
				bxx* {LABEL, $2}

	/* Pop 2 doubles, branch if... */
	pat cmf zeq $1==8    call cmf8zxx("beq")
	pat cmf zne $1==8    call cmf8zxx("bne")
	pat cmf zgt $1==8    call cmf8zxx("bgt")
	pat cmf zge $1==8    call cmf8zxx("bge")
	pat cmf zlt $1==8    call cmf8zxx("blt")
	pat cmf zle $1==8    call cmf8zxx("ble")

	/* Convert double to single */
	/*   reg_float pattern must be first, or it goes unused! */
	pat loc loc cff stl $1==8 && $2==4 && inreg($4)==reg_float
		with FREG
			gen frsp {LOCAL, $4}, %1
	pat loc loc cff $1==8 && $2==4
		with FREG
			uses reusing %1, FSREG
			gen frsp %a, %1
			yields %a

	pat loc loc cfi $1==8 && $2==4     /* Double to signed int */
		with FREG STACK
			uses reusing %1, FREG
			gen
				fctiwz %a, %1
				stfdu %a, {IND_RC_D, sp, 0-8}
				addi sp, sp, {C, 4}

	pat loc loc cfu $1==8 && $2==4     /* Double to unsigned int */
		leaving cal ".cfu8"

	pat loc loc cif $1==4 && $2==8     /* Signed int to double */
		leaving cal ".cif8"

	pat loc loc cuf $1==4 && $2==8     /* Unsigned int to double */
		leaving cal ".cuf8"

	pat fef $1==8                      /* Split fraction, exponent */
		leaving cal ".fef8"

	/* Multiply two doubles, then split fraction, integer */
	pat fif $1==8
		leaving cal ".fif8"