/**************************************************************************
 *
 * Copyright (C) 2008 Tungsten Graphics, Inc.   All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 **************************************************************************/

/**
 * PPC code generation.
 * For reference, see http://www.power.org/resources/reading/PowerISA_V2.05.pdf
 * ABI info: http://www.cs.utsa.edu/~whaley/teach/cs6463FHPO/LEC/lec12_ho.pdf
 *
 * Other PPC refs:
 * http://www-01.ibm.com/chips/techlib/techlib.nsf/techdocs/852569B20050FF778525699600719DF2
 * http://www.ibm.com/developerworks/eserver/library/es-archguide-v2.html
 * http://www.freescale.com/files/product/doc/MPCFPE32B.pdf
 *
 * \author Brian Paul
 */


#include <stdio.h>
#include "util/u_memory.h"
#include "pipe/p_debug.h"
#include "rtasm_ppc.h"


void
ppc_init_func(struct ppc_function *p, unsigned max_inst)
{
   uint i;

   p->store = align_malloc(max_inst * PPC_INST_SIZE, 16);
   p->num_inst = 0;
   p->max_inst = max_inst;
   p->fp_used = ~0x0;
   p->vec_used = ~0x0;

   /* only allow using gp registers 7..12 for now */
   p->reg_used = 0x0;
   for (i = 7; i < 13; i++)
      p->reg_used |= (1 << i);
}


void
ppc_release_func(struct ppc_function *p)
{
   assert(p->num_inst <= p->max_inst);
   if (p->store != NULL) {
      align_free(p->store);
   }
   p->store = NULL;
}


void (*ppc_get_func(struct ppc_function *p))(void)
{
#if 0
   DUMP_END();
   if (DISASSEM && p->store)
      debug_printf("disassemble %p %p\n", p->store, p->csr);

   if (p->store == p->error_overflow)
      return (void (*)(void)) NULL;
   else
#endif
      return (void (*)(void)) p->store;
}


void
ppc_dump_func(const struct ppc_function *p)
{
   uint i;
   for (i = 0; i < p->num_inst; i++) {
      debug_printf("%3u: 0x%08x\n", i, p->store[i]);
   }
}


/**
 * Allocate a general purpose register.
 * \return register index or -1 if none left.
 */
int
ppc_allocate_register(struct ppc_function *p)
{
   unsigned i;
   for (i = 0; i < PPC_NUM_REGS; i++) {
      const uint64_t mask = 1 << i;
      if ((p->reg_used & mask) != 0) {
         p->reg_used &= ~mask;
         return i;
      }
   }
   return -1;
}


/**
 * Mark the given general purpose register as "unallocated".
 */
void
ppc_release_register(struct ppc_function *p, int reg)
{
   assert(reg < PPC_NUM_REGS);
   assert((p->reg_used & (1 << reg)) == 0);
   p->reg_used |= (1 << reg);
}


/**
 * Allocate a floating point register.
 * \return register index or -1 if none left.
 */
int
ppc_allocate_fp_register(struct ppc_function *p)
{
   unsigned i;
   for (i = 0; i < PPC_NUM_FP_REGS; i++) {
      const uint64_t mask = 1 << i;
      if ((p->fp_used & mask) != 0) {
         p->fp_used &= ~mask;
         return i;
      }
   }
   return -1;
}


/**
 * Mark the given floating point register as "unallocated".
 */
void
ppc_release_fp_register(struct ppc_function *p, int reg)
{
   assert(reg < PPC_NUM_FP_REGS);
   assert((p->fp_used & (1 << reg)) == 0);
   p->fp_used |= (1 << reg);
}


/**
 * Allocate a vector register.
 * \return register index or -1 if none left.
 */
int
ppc_allocate_vec_register(struct ppc_function *p)
{
   unsigned i;
   for (i = 0; i < PPC_NUM_VEC_REGS; i++) {
      const uint64_t mask = 1 << i;
      if ((p->vec_used & mask) != 0) {
         p->vec_used &= ~mask;
         return i;
      }
   }
   return -1;
}


/**
 * Mark the given vector register as "unallocated".
 */
void
ppc_release_vec_register(struct ppc_function *p, int reg)
{
   assert(reg < PPC_NUM_VEC_REGS);
   assert((p->vec_used & (1 << reg)) == 0);
   p->vec_used |= (1 << reg);
}



union vx_inst {
   uint32_t bits;
   struct {
      unsigned op:6;
      unsigned vD:5;
      unsigned vA:5;
      unsigned vB:5;
      unsigned op2:11;
   } inst;
};

static inline void
emit_vx(struct ppc_function *p, uint op2, uint vD, uint vA, uint vB)
{
   union vx_inst inst;
   inst.inst.op = 4;
   inst.inst.vD = vD;
   inst.inst.vA = vA;
   inst.inst.vB = vB;
   inst.inst.op2 = op2;
   p->store[p->num_inst++] = inst.bits;
   assert(p->num_inst <= p->max_inst);
};


union vxr_inst {
   uint32_t bits;
   struct {
      unsigned op:6;
      unsigned vD:5;
      unsigned vA:5;
      unsigned vB:5;
      unsigned rC:1;
      unsigned op2:10;
   } inst;
};

static inline void
emit_vxr(struct ppc_function *p, uint op2, uint vD, uint vA, uint vB)
{
   union vxr_inst inst;
   inst.inst.op = 4;
   inst.inst.vD = vD;
   inst.inst.vA = vA;
   inst.inst.vB = vB;
   inst.inst.rC = 0;
   inst.inst.op2 = op2;
   p->store[p->num_inst++] = inst.bits;
   assert(p->num_inst <= p->max_inst);
};


union va_inst {
   uint32_t bits;
   struct {
      unsigned op:6;
      unsigned vD:5;
      unsigned vA:5;
      unsigned vB:5;
      unsigned vC:5;
      unsigned op2:6;
   } inst;
};

static inline void
emit_va(struct ppc_function *p, uint op2, uint vD, uint vA, uint vB, uint vC)
{
   union va_inst inst;
   inst.inst.op = 4;
   inst.inst.vD = vD;
   inst.inst.vA = vA;
   inst.inst.vB = vB;
   inst.inst.vC = vC;
   inst.inst.op2 = op2;
   p->store[p->num_inst++] = inst.bits;
   assert(p->num_inst <= p->max_inst);
};


union i_inst {
   uint32_t bits;
   struct {
      unsigned op:6;
      unsigned li:24;
      unsigned aa:1;
      unsigned lk:1;
   } inst;
};

static INLINE void
emit_i(struct ppc_function *p, uint op, uint li, uint aa, uint lk)
{
   union i_inst inst;
   inst.inst.op = op;
   inst.inst.li = li;
   inst.inst.aa = aa;
   inst.inst.lk = lk;
   p->store[p->num_inst++] = inst.bits;
   assert(p->num_inst <= p->max_inst);
}


union xl_inst {
   uint32_t bits;
   struct {
      unsigned op:6;
      unsigned bo:5;
      unsigned bi:5;
      unsigned unused:3;
      unsigned bh:2;
      unsigned op2:10;
      unsigned lk:1;
   } inst;
};

static INLINE void
emit_xl(struct ppc_function *p, uint op, uint bo, uint bi, uint bh,
        uint op2, uint lk)
{
   union xl_inst inst;
   inst.inst.op = op;
   inst.inst.bo = bo;
   inst.inst.bi = bi;
   inst.inst.unused = 0x0;
   inst.inst.bh = bh;
   inst.inst.op2 = op2;
   inst.inst.lk = lk;
   p->store[p->num_inst++] = inst.bits;
   assert(p->num_inst <= p->max_inst);
}

static INLINE void
dump_xl(const char *name, uint inst)
{
   union xl_inst i;

   i.bits = inst;
   debug_printf("%s = 0x%08x\n", name, inst);
   debug_printf(" op: %d 0x%x\n", i.inst.op, i.inst.op);
   debug_printf(" bo: %d 0x%x\n", i.inst.bo, i.inst.bo);
   debug_printf(" bi: %d 0x%x\n", i.inst.bi, i.inst.bi);
   debug_printf(" unused: %d 0x%x\n", i.inst.unused, i.inst.unused);
   debug_printf(" bh: %d 0x%x\n", i.inst.bh, i.inst.bh);
   debug_printf(" op2: %d 0x%x\n", i.inst.op2, i.inst.op2);
   debug_printf(" lk: %d 0x%x\n", i.inst.lk, i.inst.lk);
}


union x_inst {
   uint32_t bits;
   struct {
      unsigned op:6;
      unsigned vrs:5;
      unsigned ra:5;
      unsigned rb:5;
      unsigned op2:10;
      unsigned unused:1;
   } inst;
};

static INLINE void
emit_x(struct ppc_function *p, uint op, uint vrs, uint ra, uint rb, uint op2)
{
   union x_inst inst;
   inst.inst.op = op;
   inst.inst.vrs = vrs;
   inst.inst.ra = ra;
   inst.inst.rb = rb;
   inst.inst.op2 = op2;
   inst.inst.unused = 0x0;
   p->store[p->num_inst++] = inst.bits;
   assert(p->num_inst <= p->max_inst);
}


union d_inst {
   uint32_t bits;
   struct {
      unsigned op:6;
      unsigned rt:5;
      unsigned ra:5;
      unsigned si:16;
   } inst;
};

static inline void
emit_d(struct ppc_function *p, uint op, uint rt, uint ra, int si)
{
   union d_inst inst;
   assert(si >= -32768);
   assert(si <= 32767);
   inst.inst.op = op;
   inst.inst.rt = rt;
   inst.inst.ra = ra;
   inst.inst.si = (unsigned) (si & 0xffff);
   p->store[p->num_inst++] = inst.bits;
   assert(p->num_inst <= p->max_inst);
};


union a_inst {
   uint32_t bits;
   struct {
      unsigned op:6;
      unsigned frt:5;
      unsigned fra:5;
      unsigned frb:5;
      unsigned unused:5;
      unsigned op2:5;
      unsigned rc:1;
   } inst;
};

static inline void
emit_a(struct ppc_function *p, uint op, uint frt, uint fra, uint frb, uint op2,
       uint rc)
{
   union a_inst inst;
   inst.inst.op = op;
   inst.inst.frt = frt;
   inst.inst.fra = fra;
   inst.inst.frb = frb;
   inst.inst.unused = 0x0;
   inst.inst.op2 = op2;
   inst.inst.rc = rc;
   p->store[p->num_inst++] = inst.bits;
   assert(p->num_inst <= p->max_inst);
};


union xo_inst {
   uint32_t bits;
   struct {
      unsigned op:6;
      unsigned rt:5;
      unsigned ra:5;
      unsigned rb:5;
      unsigned oe:1;
      unsigned op2:9;
      unsigned rc:1;
   } inst;
};

static INLINE void
emit_xo(struct ppc_function *p, uint op, uint rt, uint ra, uint rb, uint oe,
        uint op2, uint rc)
{
   union xo_inst inst;
   inst.inst.op = op;
   inst.inst.rt = rt;
   inst.inst.ra = ra;
   inst.inst.rb = rb;
   inst.inst.oe = oe;
   inst.inst.op2 = op2;
   inst.inst.rc = rc;
   p->store[p->num_inst++] = inst.bits;
   assert(p->num_inst <= p->max_inst);
}





/**
 ** float vector arithmetic
 **/

/** vector float add */
void
ppc_vaddfp(struct ppc_function *p, uint vD, uint vA, uint vB)
{
   emit_vx(p, 10, vD, vA, vB);
}

/** vector float substract */
void
ppc_vsubfp(struct ppc_function *p, uint vD, uint vA, uint vB)
{
   emit_vx(p, 74, vD, vA, vB);
}

/** vector float min */
void
ppc_vminfp(struct ppc_function *p, uint vD, uint vA, uint vB)
{
   emit_vx(p, 1098, vD, vA, vB);
}

/** vector float max */
void
ppc_vmaxfp(struct ppc_function *p, uint vD, uint vA, uint vB)
{
   emit_vx(p, 1034, vD, vA, vB);
}

/** vector float mult add: vD = vA * vB + vC */
void
ppc_vmaddfp(struct ppc_function *p, uint vD, uint vA, uint vB, uint vC)
{
   emit_va(p, 46, vD, vA, vC, vB); /* note arg order */
}

/** vector float compare greater than */
void
ppc_vcmpgtfpx(struct ppc_function *p, uint vD, uint vA, uint vB)
{
   emit_vxr(p, 710, vD, vA, vB);
}

/** vector float compare greater than or equal to */
void
ppc_vcmpgefpx(struct ppc_function *p, uint vD, uint vA, uint vB)
{
   emit_vxr(p, 454, vD, vA, vB);
}

/** vector float compare equal */
void
ppc_vcmpeqfpx(struct ppc_function *p, uint vD, uint vA, uint vB)
{
   emit_vxr(p, 198, vD, vA, vB);
}

/** vector float 2^x */
void
ppc_vexptefp(struct ppc_function *p, uint vD, uint vB)
{
   emit_vx(p, 394, vD, 0, vB);
}

/** vector float log2(x) */
void
ppc_vlogefp(struct ppc_function *p, uint vD, uint vB)
{
   emit_vx(p, 458, vD, 0, vB);
}

/** vector float reciprocol */
void
ppc_vrefp(struct ppc_function *p, uint vD, uint vB)
{
   emit_vx(p, 266, vD, 0, vB);
}

/** vector float reciprocol sqrt estimate */
void
ppc_vrsqrtefp(struct ppc_function *p, uint vD, uint vB)
{
   emit_vx(p, 330, vD, 0, vB);
}

/** vector float round to negative infinity */
void
ppc_vrfim(struct ppc_function *p, uint vD, uint vB)
{
   emit_vx(p, 714, vD, 0, vB);
}

/** vector float round to positive infinity */
void
ppc_vrfip(struct ppc_function *p, uint vD, uint vB)
{
   emit_vx(p, 650, vD, 0, vB);
}

/** vector float round to nearest int */
void
ppc_vrfin(struct ppc_function *p, uint vD, uint vB)
{
   emit_vx(p, 522, vD, 0, vB);
}

/** vector float round to int toward zero */
void
ppc_vrfiz(struct ppc_function *p, uint vD, uint vB)
{
   emit_vx(p, 586, vD, 0, vB);
}

/** vector store: store vR at mem[vA+vB] */
void
ppc_stvx(struct ppc_function *p, uint vR, uint vA, uint vB)
{
   emit_x(p, 31, vR, vA, vB, 231);
}

/** vector load: vR = mem[vA+vB] */
void
ppc_lvx(struct ppc_function *p, uint vR, uint vA, uint vB)
{
   emit_x(p, 31, vR, vA, vB, 103);
}



/**
 ** vector bitwise operations
 **/

/** vector and */
void
ppc_vand(struct ppc_function *p, uint vD, uint vA, uint vB)
{
   emit_vx(p, 1028, vD, vA, vB);
}

/** vector and complement */
void
ppc_vandc(struct ppc_function *p, uint vD, uint vA, uint vB)
{
   emit_vx(p, 1092, vD, vA, vB);
}

/** vector or */
void
ppc_vor(struct ppc_function *p, uint vD, uint vA, uint vB)
{
   emit_vx(p, 1156, vD, vA, vB);
}

/** vector nor */
void
ppc_vnor(struct ppc_function *p, uint vD, uint vA, uint vB)
{
   emit_vx(p, 1284, vD, vA, vB);
}

/** vector xor */
void
ppc_vxor(struct ppc_function *p, uint vD, uint vA, uint vB)
{
   emit_vx(p, 1220, vD, vA, vB);
}

/** Pseudo-instruction: vector move */
void
ppc_vecmove(struct ppc_function *p, uint vD, uint vA)
{
   ppc_vor(p, vD, vA, vA);
}



/**
 ** Vector shuffle / select / splat / etc
 **/

/** vector permute */
void
ppc_vperm(struct ppc_function *p, uint vD, uint vA, uint vB, uint vC)
{
   emit_va(p, 43, vD, vA, vB, vC);
}

/** vector select */
void
ppc_vsel(struct ppc_function *p, uint vD, uint vA, uint vB, uint vC)
{
   emit_va(p, 42, vD, vA, vB, vC);
}

/** vector splat byte */
void
ppc_vspltb(struct ppc_function *p, uint vD, uint vB, uint imm)
{
   emit_vx(p, 42, vD, imm, vB);
}

/** vector splat half word */
void
ppc_vsplthw(struct ppc_function *p, uint vD, uint vB, uint imm)
{
   emit_vx(p, 588, vD, imm, vB);
}

/** vector splat word */
void
ppc_vspltw(struct ppc_function *p, uint vD, uint vB, uint imm)
{
   emit_vx(p, 652, vD, imm, vB);
}

/** vector splat signed immediate word */
void
ppc_vspltisw(struct ppc_function *p, uint vD, int imm)
{
   assert(imm >= -16);
   assert(imm < 15);
   emit_vx(p, 908, vD, imm, 0);
}

/** vector shift left word: vD[word] = vA[word] << (vB[word] & 0x1f) */
void
ppc_vslw(struct ppc_function *p, uint vD, uint vA, uint vB)
{
   emit_vx(p, 388, vD, vA, vB);
}




/**
 ** integer arithmetic
 **/

/** rt = ra + imm */
void
ppc_addi(struct ppc_function *p, uint rt, uint ra, int imm)
{
   emit_d(p, 14, rt, ra, imm);
}

/** rt = ra + (imm << 16) */
void
ppc_addis(struct ppc_function *p, uint rt, uint ra, int imm)
{
   emit_d(p, 15, rt, ra, imm);
}

/** rt = ra + rb */
void
ppc_add(struct ppc_function *p, uint rt, uint ra, uint rb)
{
   emit_xo(p, 31, rt, ra, rb, 0, 266, 0);
}

/** rt = ra AND ra */
void
ppc_and(struct ppc_function *p, uint rt, uint ra, uint rb)
{
   emit_x(p, 31, ra, rt, rb, 28);  /* note argument order */
}

/** rt = ra AND imm */
void
ppc_andi(struct ppc_function *p, uint rt, uint ra, int imm)
{
   emit_d(p, 28, ra, rt, imm);  /* note argument order */
}

/** rt = ra OR ra */
void
ppc_or(struct ppc_function *p, uint rt, uint ra, uint rb)
{
   emit_x(p, 31, ra, rt, rb, 444);  /* note argument order */
}

/** rt = ra OR imm */
void
ppc_ori(struct ppc_function *p, uint rt, uint ra, int imm)
{
   emit_d(p, 24, ra, rt, imm);  /* note argument order */
}

/** rt = ra XOR ra */
void
ppc_xor(struct ppc_function *p, uint rt, uint ra, uint rb)
{
   emit_x(p, 31, ra, rt, rb, 316);  /* note argument order */
}

/** rt = ra XOR imm */
void
ppc_xori(struct ppc_function *p, uint rt, uint ra, int imm)
{
   emit_d(p, 26, ra, rt, imm);  /* note argument order */
}

/** pseudo instruction: move: rt = ra */
void
ppc_mr(struct ppc_function *p, uint rt, uint ra)
{
   ppc_or(p, rt, ra, ra);
}

/** pseudo instruction: load immediate: rt = imm */
void
ppc_li(struct ppc_function *p, uint rt, int imm)
{
   ppc_addi(p, rt, 0, imm);
}

/** rt = imm << 16 */
void
ppc_lis(struct ppc_function *p, uint rt, int imm)
{
   ppc_addis(p, rt, 0, imm);
}

/** rt = imm */
void
ppc_load_int(struct ppc_function *p, uint rt, int imm)
{
   ppc_lis(p, rt, (imm >> 16));          /* rt = imm >> 16 */
   ppc_ori(p, rt, rt, (imm & 0xffff));   /* rt = rt | (imm & 0xffff) */
}




/**
 ** integer load/store
 **/

/** store rs at memory[(ra)+d],
 * then update ra = (ra)+d
 */
void
ppc_stwu(struct ppc_function *p, uint rs, uint ra, int d)
{
   emit_d(p, 37, rs, ra, d);
}

/** store rs at memory[(ra)+d] */
void
ppc_stw(struct ppc_function *p, uint rs, uint ra, int d)
{
   emit_d(p, 36, rs, ra, d);
}

/** Load rt = mem[(ra)+d];  then zero set high 32 bits to zero. */
void
ppc_lwz(struct ppc_function *p, uint rt, uint ra, int d)
{
   emit_d(p, 32, rt, ra, d);
}



/**
 ** Float (non-vector) arithmetic
 **/

/** add: frt = fra + frb */
void
ppc_fadd(struct ppc_function *p, uint frt, uint fra, uint frb)
{
   emit_a(p, 63, frt, fra, frb, 21, 0);
}

/** sub: frt = fra - frb */
void
ppc_fsub(struct ppc_function *p, uint frt, uint fra, uint frb)
{
   emit_a(p, 63, frt, fra, frb, 20, 0);
}

/** convert to int: rt = (int) ra */
void
ppc_fctiwz(struct ppc_function *p, uint rt, uint fra)
{
   emit_x(p, 63, rt, 0, fra, 15);
}

/** store frs at mem[(ra)+offset] */
void
ppc_stfs(struct ppc_function *p, uint frs, uint ra, int offset)
{
   emit_d(p, 52, frs, ra, offset);
}

/** store frs at mem[(ra)+(rb)] */
void
ppc_stfiwx(struct ppc_function *p, uint frs, uint ra, uint rb)
{
   emit_x(p, 31, frs, ra, rb, 983);
}

/** load frt = mem[(ra)+offset] */
void
ppc_lfs(struct ppc_function *p, uint frt, uint ra, int offset)
{
   emit_d(p, 48, frt, ra, offset);
}





/**
 ** branch instructions
 **/

/** BLR: Branch to link register (p. 35) */
void
ppc_blr(struct ppc_function *p)
{
   emit_i(p, 18, 0, 0, 1);
}

/** Branch Conditional to Link Register (p. 36) */
void
ppc_bclr(struct ppc_function *p, uint condOp, uint branchHint, uint condReg)
{
   emit_xl(p, 19, condOp, condReg, branchHint, 16, 0);
}

/** Pseudo instruction: return from subroutine */
void
ppc_return(struct ppc_function *p)
{
   ppc_bclr(p, BRANCH_COND_ALWAYS, BRANCH_HINT_SUB_RETURN, 0);
}