x86sse.c

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#if defined(__i386__) || defined(__386__)

#include "imports.h"
#include "x86sse.h"

#define DISASSEM 0
#define X86_TWOB 0x0f

static unsigned char *cptr( void (*label)() )
{
   return (unsigned char *)(unsigned long)label;
}


static void do_realloc( struct x86_function *p )
{
   if (p->size == 0) {
      p->size = 1024;
      p->store = _mesa_exec_malloc(p->size);
      p->csr = p->store;
   }
   else {
      unsigned used = p->csr - p->store;
      unsigned char *tmp = p->store;
      p->size *= 2;
      p->store = _mesa_exec_malloc(p->size);
      memcpy(p->store, tmp, used);
      p->csr = p->store + used;
      _mesa_exec_free(tmp);
   }
}

/* Emit bytes to the instruction stream:
 */
static unsigned char *reserve( struct x86_function *p, int bytes )
{
   if (p->csr + bytes - p->store > p->size)
      do_realloc(p);

   {
      unsigned char *csr = p->csr;
      p->csr += bytes;
      return csr;
   }
}



static void emit_1b( struct x86_function *p, char b0 )
{
   char *csr = (char *)reserve(p, 1);
   *csr = b0;
}

static void emit_1i( struct x86_function *p, int i0 )
{
   int *icsr = (int *)reserve(p, sizeof(i0));
   *icsr = i0;
}

static void emit_1ub( struct x86_function *p, unsigned char b0 )
{
   unsigned char *csr = reserve(p, 1);
   *csr++ = b0;
}

static void emit_2ub( struct x86_function *p, unsigned char b0, unsigned char b1 )
{
   unsigned char *csr = reserve(p, 2);
   *csr++ = b0;
   *csr++ = b1;
}

static void emit_3ub( struct x86_function *p, unsigned char b0, unsigned char b1, unsigned char b2 )
{
   unsigned char *csr = reserve(p, 3);
   *csr++ = b0;
   *csr++ = b1;
   *csr++ = b2;
}


/* Build a modRM byte + possible displacement.  No treatment of SIB
 * indexing.  BZZT - no way to encode an absolute address.
 */
static void emit_modrm( struct x86_function *p, 
			struct x86_reg reg, 
			struct x86_reg regmem )
{
   unsigned char val = 0;
   
   assert(reg.mod == mod_REG);
   
   val |= regmem.mod << 6;     	/* mod field */
   val |= reg.idx << 3;		/* reg field */
   val |= regmem.idx;		/* r/m field */
   
   emit_1ub(p, val);

   /* Oh-oh we've stumbled into the SIB thing.
    */
   if (regmem.file == file_REG32 &&
       regmem.idx == reg_SP) {
      emit_1ub(p, 0x24);		/* simplistic! */
   }

   switch (regmem.mod) {
   case mod_REG:
   case mod_INDIRECT:
      break;
   case mod_DISP8:
      emit_1b(p, regmem.disp);
      break;
   case mod_DISP32:
      emit_1i(p, regmem.disp);
      break;
   default:
      assert(0);
      break;
   }
}


static void emit_modrm_noreg( struct x86_function *p,
			      unsigned op,
			      struct x86_reg regmem )
{
   struct x86_reg dummy = x86_make_reg(file_REG32, op);
   emit_modrm(p, dummy, regmem);
}

/* Many x86 instructions have two opcodes to cope with the situations
 * where the destination is a register or memory reference
 * respectively.  This function selects the correct opcode based on
 * the arguments presented.
 */
static void emit_op_modrm( struct x86_function *p,
			   unsigned char op_dst_is_reg, 
			   unsigned char op_dst_is_mem,
			   struct x86_reg dst,
			   struct x86_reg src )
{  
   switch (dst.mod) {
   case mod_REG:
      emit_1ub(p, op_dst_is_reg);
      emit_modrm(p, dst, src);
      break;
   case mod_INDIRECT:
   case mod_DISP32:
   case mod_DISP8:
      assert(src.mod == mod_REG);
      emit_1ub(p, op_dst_is_mem);
      emit_modrm(p, src, dst);
      break;
   default:
      assert(0);
      break;
   }
}







/* Create and manipulate registers and regmem values:
 */
struct x86_reg x86_make_reg( enum x86_reg_file file,
			     enum x86_reg_name idx )
{
   struct x86_reg reg;

   reg.file = file;
   reg.idx = idx;
   reg.mod = mod_REG;
   reg.disp = 0;

   return reg;
}

struct x86_reg x86_make_disp( struct x86_reg reg,
			      int disp )
{
   assert(reg.file == file_REG32);

   if (reg.mod == mod_REG)
      reg.disp = disp;
   else
      reg.disp += disp;

   if (reg.disp == 0)
      reg.mod = mod_INDIRECT;
   else if (reg.disp <= 127 && reg.disp >= -128)
      reg.mod = mod_DISP8;
   else
      reg.mod = mod_DISP32;

   return reg;
}

struct x86_reg x86_deref( struct x86_reg reg )
{
   return x86_make_disp(reg, 0);
}

struct x86_reg x86_get_base_reg( struct x86_reg reg )
{
   return x86_make_reg( reg.file, reg.idx );
}

unsigned char *x86_get_label( struct x86_function *p )
{
   return p->csr;
}



/***********************************************************************
 * x86 instructions
 */


void x86_jcc( struct x86_function *p,
	      enum x86_cc cc,
	      unsigned char *label )
{
   int offset = label - (x86_get_label(p) + 2);
   
   if (offset <= 127 && offset >= -128) {
      emit_1ub(p, 0x70 + cc);
      emit_1b(p, (char) offset);
   }
   else {
      offset = label - (x86_get_label(p) + 6);
      emit_2ub(p, 0x0f, 0x80 + cc);
      emit_1i(p, offset);
   }
}

/* Always use a 32bit offset for forward jumps:
 */
unsigned char *x86_jcc_forward( struct x86_function *p,
			  enum x86_cc cc )
{
   emit_2ub(p, 0x0f, 0x80 + cc);
   emit_1i(p, 0);
   return x86_get_label(p);
}

unsigned char *x86_jmp_forward( struct x86_function *p)
{
   emit_1ub(p, 0xe9);
   emit_1i(p, 0);
   return x86_get_label(p);
}

unsigned char *x86_call_forward( struct x86_function *p)
{
   emit_1ub(p, 0xe8);
   emit_1i(p, 0);
   return x86_get_label(p);
}

/* Fixup offset from forward jump:
 */
void x86_fixup_fwd_jump( struct x86_function *p,
			 unsigned char *fixup )
{
   *(int *)(fixup - 4) = x86_get_label(p) - fixup;
}

void x86_jmp( struct x86_function *p, unsigned char *label)
{
   emit_1ub(p, 0xe9);
   emit_1i(p, label - x86_get_label(p) - 4);
}

#if 0
/* This doesn't work once we start reallocating & copying the
 * generated code on buffer fills, because the call is relative to the
 * current pc.
 */
void x86_call( struct x86_function *p, void (*label)())
{
   emit_1ub(p, 0xe8);
   emit_1i(p, cptr(label) - x86_get_label(p) - 4);
}
#else
void x86_call( struct x86_function *p, struct x86_reg reg)
{
   emit_1ub(p, 0xff);
   emit_modrm(p, reg, reg);
}
#endif


/* michal:
 * Temporary. As I need immediate operands, and dont want to mess with the codegen,
 * I load the immediate into general purpose register and use it.
 */
void x86_mov_reg_imm( struct x86_function *p, struct x86_reg dst, int imm )
{
   assert(dst.mod == mod_REG);
   emit_1ub(p, 0xb8 + dst.idx);
   emit_1i(p, imm);
}

void x86_push( struct x86_function *p,
	       struct x86_reg reg )
{
   assert(reg.mod == mod_REG);
   emit_1ub(p, 0x50 + reg.idx);
   p->stack_offset += 4;
}

void x86_pop( struct x86_function *p,
	      struct x86_reg reg )
{
   assert(reg.mod == mod_REG);
   emit_1ub(p, 0x58 + reg.idx);
   p->stack_offset -= 4;
}

void x86_inc( struct x86_function *p,
	      struct x86_reg reg )
{
   assert(reg.mod == mod_REG);
   emit_1ub(p, 0x40 + reg.idx);
}

void x86_dec( struct x86_function *p,
	      struct x86_reg reg )
{
   assert(reg.mod == mod_REG);
   emit_1ub(p, 0x48 + reg.idx);
}

void x86_ret( struct x86_function *p )
{
   emit_1ub(p, 0xc3);
}

void x86_sahf( struct x86_function *p )
{
   emit_1ub(p, 0x9e);
}

void x86_mov( struct x86_function *p,
	      struct x86_reg dst,
	      struct x86_reg src )
{
   emit_op_modrm( p, 0x8b, 0x89, dst, src );
}

void x86_xor( struct x86_function *p,
	      struct x86_reg dst,
	      struct x86_reg src )
{
   emit_op_modrm( p, 0x33, 0x31, dst, src );
}

void x86_cmp( struct x86_function *p,
	      struct x86_reg dst,
	      struct x86_reg src )
{
   emit_op_modrm( p, 0x3b, 0x39, dst, src );
}

void x86_lea( struct x86_function *p,
	      struct x86_reg dst,
	      struct x86_reg src )
{
   emit_1ub(p, 0x8d);
   emit_modrm( p, dst, src );
}

void x86_test( struct x86_function *p,
	       struct x86_reg dst,
	       struct x86_reg src )
{
   emit_1ub(p, 0x85);
   emit_modrm( p, dst, src );
}

void x86_add( struct x86_function *p,
	       struct x86_reg dst,
	       struct x86_reg src )
{
   emit_op_modrm(p, 0x03, 0x01, dst, src );
}

void x86_mul( struct x86_function *p,
	       struct x86_reg src )
{
   assert (src.file == file_REG32 && src.mod == mod_REG);
   emit_op_modrm(p, 0xf7, 0, x86_make_reg (file_REG32, reg_SP), src );
}

void x86_sub( struct x86_function *p,
	       struct x86_reg dst,
	       struct x86_reg src )
{
   emit_op_modrm(p, 0x2b, 0x29, dst, src );
}

void x86_or( struct x86_function *p,
             struct x86_reg dst,
             struct x86_reg src )
{
   emit_op_modrm( p, 0x0b, 0x09, dst, src );
}

void x86_and( struct x86_function *p,
              struct x86_reg dst,
              struct x86_reg src )
{
   emit_op_modrm( p, 0x23, 0x21, dst, src );
}



/***********************************************************************
 * SSE instructions
 */


void sse_movss( struct x86_function *p,
		struct x86_reg dst,
		struct x86_reg src )
{
   emit_2ub(p, 0xF3, X86_TWOB);
   emit_op_modrm( p, 0x10, 0x11, dst, src );
}

void sse_movaps( struct x86_function *p,
		 struct x86_reg dst,
		 struct x86_reg src )
{
   emit_1ub(p, X86_TWOB);
   emit_op_modrm( p, 0x28, 0x29, dst, src );
}

void sse_movups( struct x86_function *p,
		 struct x86_reg dst,
		 struct x86_reg src )
{
   emit_1ub(p, X86_TWOB);
   emit_op_modrm( p, 0x10, 0x11, dst, src );
}

void sse_movhps( struct x86_function *p,
		 struct x86_reg dst,
		 struct x86_reg src )
{
   assert(dst.mod != mod_REG || src.mod != mod_REG);
   emit_1ub(p, X86_TWOB);
   emit_op_modrm( p, 0x16, 0x17, dst, src ); /* cf movlhps */
}

void sse_movlps( struct x86_function *p,
		 struct x86_reg dst,
		 struct x86_reg src )
{
   assert(dst.mod != mod_REG || src.mod != mod_REG);
   emit_1ub(p, X86_TWOB);
   emit_op_modrm( p, 0x12, 0x13, dst, src ); /* cf movhlps */
}

void sse_maxps( struct x86_function *p,
		struct x86_reg dst,
		struct x86_reg src )
{
   emit_2ub(p, X86_TWOB, 0x5F);
   emit_modrm( p, dst, src );
}

void sse_maxss( struct x86_function *p,
		struct x86_reg dst,
		struct x86_reg src )
{
   emit_3ub(p, 0xF3, X86_TWOB, 0x5F);
   emit_modrm( p, dst, src );
}

void sse_divss( struct x86_function *p,
		struct x86_reg dst,
		struct x86_reg src )
{
   emit_3ub(p, 0xF3, X86_TWOB, 0x5E);
   emit_modrm( p, dst, src );
}

void sse_minps( struct x86_function *p,
		struct x86_reg dst,
		struct x86_reg src )
{
   emit_2ub(p, X86_TWOB, 0x5D);
   emit_modrm( p, dst, src );
}

void sse_subps( struct x86_function *p,
		struct x86_reg dst,
		struct x86_reg src )
{
   emit_2ub(p, X86_TWOB, 0x5C);
   emit_modrm( p, dst, src );
}

void sse_mulps( struct x86_function *p,
		struct x86_reg dst,
		struct x86_reg src )
{
   emit_2ub(p, X86_TWOB, 0x59);
   emit_modrm( p, dst, src );
}

void sse_mulss( struct x86_function *p,
		struct x86_reg dst,
		struct x86_reg src )
{
   emit_3ub(p, 0xF3, X86_TWOB, 0x59);
   emit_modrm( p, dst, src );
}

void sse_addps( struct x86_function *p,
		struct x86_reg dst,
		struct x86_reg src )
{
   emit_2ub(p, X86_TWOB, 0x58);
   emit_modrm( p, dst, src );
}

void sse_addss( struct x86_function *p,
		struct x86_reg dst,
		struct x86_reg src )
{
   emit_3ub(p, 0xF3, X86_TWOB, 0x58);
   emit_modrm( p, dst, src );
}

void sse_andnps( struct x86_function *p,
                 struct x86_reg dst,
                 struct x86_reg src )
{
   emit_2ub(p, X86_TWOB, 0x55);
   emit_modrm( p, dst, src );
}

void sse_andps( struct x86_function *p,
		struct x86_reg dst,
		struct x86_reg src )
{
   emit_2ub(p, X86_TWOB, 0x54);
   emit_modrm( p, dst, src );
}

void sse_rsqrtps( struct x86_function *p,
                  struct x86_reg dst,
                  struct x86_reg src )
{
   emit_2ub(p, X86_TWOB, 0x52);
   emit_modrm( p, dst, src );
}

void sse_rsqrtss( struct x86_function *p,
		  struct x86_reg dst,
		  struct x86_reg src )
{
   emit_3ub(p, 0xF3, X86_TWOB, 0x52);
   emit_modrm( p, dst, src );

}

void sse_movhlps( struct x86_function *p,
		  struct x86_reg dst,
		  struct x86_reg src )
{
   assert(dst.mod == mod_REG && src.mod == mod_REG);
   emit_2ub(p, X86_TWOB, 0x12);
   emit_modrm( p, dst, src );
}

void sse_movlhps( struct x86_function *p,
		  struct x86_reg dst,
		  struct x86_reg src )
{
   assert(dst.mod == mod_REG && src.mod == mod_REG);
   emit_2ub(p, X86_TWOB, 0x16);
   emit_modrm( p, dst, src );
}

void sse_orps( struct x86_function *p,
               struct x86_reg dst,
               struct x86_reg src )
{
   emit_2ub(p, X86_TWOB, 0x56);
   emit_modrm( p, dst, src );