syn68k/syngen/generatecode.c

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38 KiB
C
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2008-09-26 14:25:10 +00:00
#include "common.h"
#include "list.h"
#include "generatecode.h"
#include "bitstring.h"
#include "error.h"
#include "reduce.h"
#include "uniquestring.h"
#include <assert.h>
#include <string.h>
#include <stdlib.h>
/* #define TEMPS_AT_TOP */
static char *cc_bits_string (int bits, char *buf);
static char *opcode_bits_string (int bits, const ParsedOpcodeInfo *info,
const CCVariant *var, char *buf);
static void generate_code_for_list (List *ls, int m68kop,
const ParsedOpcodeInfo *info,
const CCVariant *var);
static void binary_op_list (const char *op, List *ls, int m68kop,
const ParsedOpcodeInfo *info,
const CCVariant *var);
static List *replace_dollar_elements (List *code, int m68kop,
const ParsedOpcodeInfo *info,
const CCVariant *var);
static void handle_constant_dollar_field (List *ls, int constant,
int field_length);
static void output_c_for_amode_ptr (const Token *t, BOOL reversed);
static void generate_temp_decls (List *code);
static void transform_reg_to_var_and_decl (List *code);
/* These are used to make sure that things like preincrement
* and postdecrement (and other one-time side effects) only happen
* once even if the responsible expression occurs multiple times.
*/
static char c_preamble[8192], c_postamble[8192];
/* This routine outputs a case synop: to syn68k_c_stream. */
void
generate_c_code (const ParsedOpcodeInfo *info, const CCVariant *var,
int m68kop, int synop, SymbolTable *sym,
const char *operand_decls, const char *postcode,
const OpcodeMappingInfo *map)
{
static const char cc_name[][16] = { "cpu_state.ccc", "cpu_state.ccn",
"cpu_state.ccv", "cpu_state.ccx",
"cpu_state.ccnz" };
char buf1[6], buf2[6], buf3[6], buf4[17];
int opcw;
List *code = copy_list (var->code);
int i;
/* Clear out preamble and postamble. */
c_preamble[0] = c_postamble[0] = '\0';
/* Replace $ elements with appropriate things. */
code = replace_dollar_elements (code, m68kop, info, var);
/* Simplify the resulting code. */
code = reduce (code, sym, 0);
/* Output human-readable comment describing this synthetic opcode. */
fprintf (syn68k_c_stream,
"\n /* %s %s ms:%s mns:%s needs:%s */\n",
info->name, opcode_bits_string (m68kop, info, var, buf4),
cc_bits_string (var->cc_may_set, buf1),
cc_bits_string (var->cc_may_not_set, buf2),
cc_bits_string (var->cc_needed, buf3));
/* Output case. */
fprintf (syn68k_c_stream, " CASE (0x%04X)\n", (unsigned) synop);
fprintf (syn68k_c_stream, " CASE_PREAMBLE (\"%s\", \"%s\", \"%s\", "
"\"%s\", \"%s\")\n",
info->name, opcode_bits_string (m68kop, info, var, buf4),
cc_bits_string (var->cc_may_set, buf1),
cc_bits_string (var->cc_may_not_set, buf2),
cc_bits_string (var->cc_needed, buf3));
/* Output operand declarations. */
fputs (operand_decls, syn68k_c_stream);
/* Transform temp variables only used as one type to temp_variables,
* and output decls for those variables.
*/
transform_reg_to_var_and_decl (code);
/* Output temp variable declarations. */
generate_temp_decls (code);
if (code->token.type != TOK_LIST)
{
parse_error (code, "Expecting code description list!\n");
return;
}
/* Output preamble. */
if (c_preamble[0] != '\0')
fprintf (syn68k_c_stream, " %s\n", c_preamble);
/* Generate the code they specified. */
fputs (" ", syn68k_c_stream);
generate_code_for_list (code, m68kop, info, var);
fputs (";\n", syn68k_c_stream);
/* Output postamble. */
if (c_postamble[0] != '\0')
fprintf (syn68k_c_stream, " %s\n", c_postamble);
/* Set any cc bits to 0 or 1 that are explicitly mentioned in the
* cc variant description. This saves the user some work generating
* the 68k description file and reduces the chance of error.
*/
for (i = 0; i < 4; i++)
if ((var->cc_to_known_value >> (4 - i)) & 1)
fprintf (syn68k_c_stream, " %s = %d;\n", cc_name[i],
(var->cc_known_values >> (4 - i)) & 1);
if (var->cc_to_known_value & 1) /* Invert sense of Z bit. */
fprintf (syn68k_c_stream, " %s = %d;\n", cc_name[4],
!(var->cc_known_values & 1));
if (postcode != NULL && postcode[0] != '\0')
fprintf (syn68k_c_stream, " %s\n", postcode);
/* Count opcode words. */
opcw = synthetic_opcode_size (map) + info->operand_words_to_skip;
/* Only adjust code ptr if we didn't just end a block. */
if (!info->ends_block)
{
/* Always increment enough so that the next opcode is guaranteed
* to be a properly aligned pointer.
*/
fprintf (syn68k_c_stream, " CASE_POSTAMBLE (ROUND_UP (%d))\n",
(int) opcw);
}
else /* If we end a block, profile the next block. */
{
/* #if !defined (__alpha) /* FIXME -- TODO -- just use __alpha case for everyone */
#if SIZEOF_CHAR_P != 8
2008-09-26 14:25:10 +00:00
fputs ("\n#ifdef PROFILE\n"
" profile_block (hash_lookup "
"(READUL (US_TO_SYN68K (code) - 4)));\n"
"#endif\n",
syn68k_c_stream);
#else
fputs ("\n#ifdef PROFILE\n"
" profile_block (hash_lookup "
"(READUL_US ((unsigned long)code - 4)));\n"
"#endif\n",
syn68k_c_stream);
#endif
#if defined (SYNCHRONOUS_INTERRUPTS) && !defined (GENERATE_NATIVE_CODE)
fprintf (syn68k_c_stream,
"#if SIZEOF_CHAR_P != 8\n"
2008-09-26 14:25:10 +00:00
" CHECK_FOR_INTERRUPT (READUL (US_TO_SYN68K (code - PTR_WORDS)));\n"
"#else\n"
" CHECK_FOR_INTERRUPT (READUL_US (code - PTR_WORDS));\n"
"#endif\n");
#endif
fprintf (syn68k_c_stream, " CASE_POSTAMBLE "
"(ROUND_UP (PTR_WORDS))\n");
}
/* Done with this instruction. */
}
/* Handy tables. */
static const char *ctypes[2][5] = {
{ "void", "uint8", "uint16", "INTERNAL_ERROR", "uint32" },
{ "void", "int8", "int16", "INTERNAL_ERROR", "int32" }
};
static const char *regdesc[2][5] = {
{ "", ".ub.n", ".uw.n", "", ".ul.n" },
{ "", ".sb.n", ".sw.n", "", ".sl.n" }
};
static void
generate_code_for_list (List *ls, int m68kop, const ParsedOpcodeInfo *info,
const CCVariant *var)
{
char buf[512];
Token *t;
BOOL done;
if (ls == NULL)
return;
/* If they have several sublists of code, generate code for each of them. */
t = &ls->token;
switch (t->type) {
/* If we've found a list, look at the operator for that list and
* generate code appropriately. */
case TOK_LIST:
if (ls->car == NULL)
return;
ls = ls->car;
t = &ls->token;
switch (ls->token.type) {
case TOK_EXPLICIT_LIST:
/* Loop over all the lists of code and generate c for them. */
for (ls = ls->cdr; ls != NULL; ls = ls->cdr)
{
generate_code_for_list (ls, m68kop, info, var);
fputs (";\n", syn68k_c_stream);
fputs (" ", syn68k_c_stream);
}
break;
case TOK_ASSIGN:
putc ('(', syn68k_c_stream);
done = FALSE;
/* If they are writing out to a long, generate appropriate code
* that will work on a QUADALIGN machine.
*/
if (ls->cdr->token.type == TOK_LIST
&& CADR (ls)->token.type == TOK_DEREF
&& CADR (ls)->token.u.derefinfo.size == 4)
{
fprintf (syn68k_c_stream,
"WRITE%cL_UNSWAPPED (SYN68K_TO_US (CLEAN (",
CADR (ls)->token.u.derefinfo.sgnd ? 'S' : 'U');
generate_code_for_list (CDADR (ls), m68kop, info, var);
fputs (")), ", syn68k_c_stream);
generate_code_for_list (CDDR (ls), m68kop, info, var);
fputs (") ", syn68k_c_stream);
done = TRUE;
}
if ((ls->cdr->token.type == TOK_AMODE
|| ls->cdr->token.type == TOK_REVERSED_AMODE
|| ls->cdr->token.type == TOK_DOLLAR_AMODE
|| ls->cdr->token.type == TOK_DOLLAR_REVERSED_AMODE)
&& ls->cdr->token.u.amodeinfo.size == 4)
{
fprintf (syn68k_c_stream,
"WRITE%cL_UNSWAPPED (SYN68K_TO_US (CLEAN (",
ls->cdr->token.u.derefinfo.sgnd ? 'S' : 'U');
switch (ls->cdr->token.type) {
case TOK_DOLLAR_AMODE:
fputs ("US_TO_SYN68K (cpu_state.amode_p) ", syn68k_c_stream);
break;
case TOK_DOLLAR_REVERSED_AMODE:
fputs ("US_TO_SYN68K (cpu_state.reversed_amode_p) ",
syn68k_c_stream);
break;
case TOK_AMODE:
ls->cdr->token.type = TOK_AMODE_PTR;
generate_code_for_list (ls->cdr, m68kop, info, var);
ls->cdr->token.type = TOK_AMODE;
break;
case TOK_REVERSED_AMODE:
default:
ls->cdr->token.type = TOK_REVERSED_AMODE_PTR;
generate_code_for_list (ls->cdr, m68kop, info, var);
ls->cdr->token.type = TOK_REVERSED_AMODE;
break;
}
fputs (")), ", syn68k_c_stream);
generate_code_for_list (CDDR (ls), m68kop, info, var);
fputs (") ", syn68k_c_stream);
done = TRUE;
}
/* Do stuff like (assign d0.ul.n (+ d0.ul.n 5)) -> "d0.ul.n += 5" */
if (!done && CDDR (ls)->token.type == TOK_LIST
&& list_length (CADDR (ls)) == 3
&& tokens_equal (&CDR (CADDR (ls))->token, &CDR (ls)->token))
{
if (CDR (ls)->token.type != TOK_LIST
|| lists_equal (CADR (ls), CADR (CADDR (ls))))
{
switch (CADDR (ls)->token.type) {
case TOK_BITWISE_AND:
case TOK_BITWISE_OR:
case TOK_BITWISE_XOR:
case TOK_PLUS:
case TOK_MINUS:
case TOK_MULTIPLY:
case TOK_DIVIDE:
case TOK_MOD:
case TOK_SHIFT_LEFT:
case TOK_SHIFT_RIGHT:
/* Word-sized operations to address registers deal with
* the entire address register; the RHS is sign extended.
*/
if (ls->cdr->token.type == TOK_ADDRESS_REGISTER
&& ls->cdr->token.u.reginfo.size == 2)
{
ls->cdr->token.u.reginfo.size = 4;
generate_code_for_list (ls->cdr, m68kop, info, var);
fputs (unparse_token (&CADDR (ls)->token, buf),
syn68k_c_stream);
fputs ("= (int16)", syn68k_c_stream);
generate_code_for_list (CDDR (CADDR (ls)), m68kop,
info, var);
}
else /* Not a word-sized op to an address register. */
{
TokenType optype = CADDR (ls)->token.type;
/* Change foo += 1 to ++foo. Why? It turns out
* that gcc sometimes generates better code for ++foo.
* Annoying, isn't it?
*/
if ((optype == TOK_PLUS || optype == TOK_MINUS)
&& CDDR (CADDR (ls))->token.type == TOK_NUMBER
&& (CDDR (CADDR (ls))->token.u.n == 1
|| CDDR (CADDR (ls))->token.u.n == -1))
{
if ((optype == TOK_PLUS)
^ (CDDR (CADDR (ls))->token.u.n == -1))
fputs ("(++", syn68k_c_stream);
else
fputs ("(--", syn68k_c_stream);
generate_code_for_list (ls->cdr, m68kop, info, var);
fputs (") ", syn68k_c_stream);
}
/* Change foo += 5 to a weird macro...this also seems
* to help gcc.
*/
else if ((optype == TOK_PLUS || optype == TOK_MINUS)
&& CDDR (CADDR (ls))->token.type == TOK_NUMBER
&& ls->cdr->token.u.reginfo.size == 4
&& ls->cdr->token.u.n != (int32) 0x80000000)
{
int32 val = CDDR (CADDR (ls))->token.u.n;
if (val >= 0)
{
if (optype == TOK_PLUS)
fputs ("(INC_VAR (", syn68k_c_stream);
else
fputs ("(DEC_VAR (", syn68k_c_stream);
generate_code_for_list (ls->cdr, m68kop, info,
var);
fprintf (syn68k_c_stream, ", %ld)) ", (long) val);
}
else /* val < 0 */
{
if (optype == TOK_PLUS)
fputs ("(DEC_VAR (", syn68k_c_stream);
else
fputs ("(INC_VAR (", syn68k_c_stream);
generate_code_for_list (ls->cdr, m68kop, info,
var);
fprintf (syn68k_c_stream, ", %ld)) ", (long) -val);
}
}
else
{
generate_code_for_list (ls->cdr, m68kop, info, var);
fputs (unparse_token (&CADDR (ls)->token, buf),
syn68k_c_stream);
fputs ("= ", syn68k_c_stream);
generate_code_for_list (CDDR (CADDR (ls)), m68kop,
info, var);
}
}
done = TRUE;
break;
default:
break;
}
}
}
/* See if we are assigning something to itself. This can happen
* when expanding out code, and gcc hasn't been eliminating these
* pointless assigns. Here we just output the LHS of the assignment,
* in case the value of the assignment as a whole is being used for
* something (eg, "d0.ul.n = d0.ul.n" -> "d0.ul.n")
*/
if (!done)
{
if (tokens_equal (&ls->cdr->token, &(CDDR (ls))->token)
&& lists_equal (CADR (ls), CADDR (ls)))
{
generate_code_for_list (ls->cdr, m68kop, info, var);
done = TRUE;
}
}
if (!done)
{
/* Force word moves into address registers to be sign extended. */
if (ls->cdr->token.type == TOK_ADDRESS_REGISTER
&& ls->cdr->token.u.reginfo.size == 2)
{
ls->cdr->token.u.reginfo.size = 4;
generate_code_for_list (ls->cdr, m68kop, info, var);
fputs ("= (int16) ", syn68k_c_stream);
}
else
{
generate_code_for_list (ls->cdr, m68kop, info, var);
fputs ("= ", syn68k_c_stream);
}
generate_code_for_list (CDDR (ls), m68kop, info, var);
}
fputs (") ", syn68k_c_stream);
break;
/* Have to special case boolean xor since C doesn't have ^^ analagous to
* && and ||.
*/
case TOK_XOR:
for (ls = ls->cdr; ls != NULL; ls = ls->cdr)
{
fputs ("(!", syn68k_c_stream);
generate_code_for_list (ls, m68kop, info, var);
fputs (") ", syn68k_c_stream);
if (ls->cdr != NULL)
fputs ("^ ", syn68k_c_stream);
}
break;
case TOK_NOT:
if (ls->cdr == NULL)
{
parse_error (ls, "\"not\" missing an argument!\n");
fputs ("0 ", syn68k_c_stream);
}
else
{
fputs ("(!", syn68k_c_stream);
generate_code_for_list (ls->cdr, m68kop, info, var);
fputs (") ", syn68k_c_stream);
}
break;
case TOK_BITWISE_NOT:
if (ls->cdr == NULL)
{
parse_error (ls, "\"~\" missing an argument!\n");
fputs ("0 ", syn68k_c_stream);
}
else
{
fputs ("(~", syn68k_c_stream);
generate_code_for_list (ls->cdr, m68kop, info, var);
fputs (") ", syn68k_c_stream);
}
break;
case TOK_AND:
binary_op_list ("&&", ls->cdr, m68kop, info, var);
break;
case TOK_OR:
binary_op_list ("||", ls->cdr, m68kop, info, var);
break;
case TOK_EQUAL:
binary_op_list ("==", ls->cdr, m68kop, info, var); /* 2 args but OK. */
break;
case TOK_NOT_EQUAL:
binary_op_list ("!=", ls->cdr, m68kop, info, var); /* 2 args but OK. */
break;
case TOK_GREATER_THAN:
case TOK_LESS_THAN:
case TOK_GREATER_OR_EQUAL:
case TOK_PLUS:
case TOK_MINUS:
case TOK_LESS_OR_EQUAL:
case TOK_MULTIPLY:
case TOK_DIVIDE:
case TOK_MOD:
case TOK_BITWISE_AND:
case TOK_BITWISE_OR:
case TOK_BITWISE_XOR:
unparse_token (&ls->token, buf);
binary_op_list (buf, ls->cdr, m68kop, info, var);
break;
case TOK_SHIFT_LEFT:
case TOK_SHIFT_RIGHT:
unparse_token (&ls->token, buf);
binary_op_list (buf, ls->cdr, m68kop, info, var);
break;
case TOK_DEFAULT:
fputs ("default ", syn68k_c_stream);
break;
case TOK_SWITCH:
fputs ("switch (", syn68k_c_stream);
generate_code_for_list (ls->cdr, m68kop, info, var);
fputs (") {\n", syn68k_c_stream);
for (ls = CDDR (ls); ls != NULL; ls = ls->cdr)
{
if (ls->car->token.type == TOK_DEFAULT)
fputs (" default: ", syn68k_c_stream);
else
{
fputs (" case ", syn68k_c_stream);
generate_code_for_list (ls->car, m68kop, info, var);
fputs (": ", syn68k_c_stream);
}
generate_code_for_list (CDAR (ls), m68kop, info, var);
fputs ("; break;\n", syn68k_c_stream);
}
fputs ("}\n ", syn68k_c_stream);
break;
case TOK_IF:
fputs ("if (", syn68k_c_stream);
generate_code_for_list (ls->cdr, m68kop, info, var);
fputs (") { ", syn68k_c_stream);
generate_code_for_list (CDDR (ls), m68kop, info, var);
fputs (";} ", syn68k_c_stream);
if (CDDDR (ls) != NULL)
{
fputs ("else { ", syn68k_c_stream);
generate_code_for_list (CDDDR (ls), m68kop, info, var);
fputs (";} ", syn68k_c_stream);
}
break;
case TOK_SWAP:
{
static const char *swap_macro[2][2][5] = {
{{ "ERR", "((uint8) (", "(SWAPUW_IFLE (", "ERR", "(SWAPUL_IFLE (" },
{ "ERR", "((int8) (", "(SWAPSW_IFLE (", "ERR", "(SWAPSL_IFLE (" }},
{{ "ERR", "((uint8) (", "(SLOW_SWAPUW_IFLE (", "ERR",
"(SLOW_SWAPUL_IFLE (" },
{ "ERR", "((int8) (", "(SLOW_SWAPSW_IFLE (", "ERR",
"(SLOW_SWAPSL_IFLE (" }}
};
fputs (swap_macro[(ls->cdr->token.type == TOK_NUMBER)]
[t->u.swapinfo.sgnd][t->u.swapinfo.size],
syn68k_c_stream);
generate_code_for_list (ls->cdr, m68kop, info, var);
fputs (")) ", syn68k_c_stream);
}
break;
case TOK_CAST:
if (ls->cdr == NULL || ls->cdr->token.type != TOK_QUOTED_STRING)
{
parse_error (ls, "\"cast\" must be followed by a C type "
"in quotes.\n");
}
else
{
fprintf (syn68k_c_stream, "((%s) ", ls->cdr->token.u.string);
generate_code_for_list (CDDR (ls), m68kop, info, var);
fputs (") ", syn68k_c_stream);
}
break;
case TOK_DEREF:
if (t->u.derefinfo.size == 0) /* Untyped deref? */
{
if (list_length (ls) != 4)
parse_error (ls, "Untyped deref requires three args (ptr type, "
"value, offset).\n");
else if (ls->cdr->token.type != TOK_QUOTED_STRING)
parse_error (ls, "Untyped deref must have second arg be "
"a quoted string C type.\n");
else
{
/* We intentionally leave out the CLEAN here; you don't
* want to CLEAN the code pointer, for instance! In general
* if you use an untyped deref you have to be more careful...
*/
fprintf (syn68k_c_stream, "(*(((%s) ",
ls->cdr->token.u.string);
generate_code_for_list (CDDR (ls), m68kop, info, var);
fputs (") + ", syn68k_c_stream);
generate_code_for_list (CDDDR (ls), m68kop, info, var);
fputs (")) ", syn68k_c_stream);
}
}
else
{
if (list_length (ls) != 2)
parse_error (ls, "Typed deref must have exactly one argument!\n");
else
{
if (t->u.derefinfo.size != 4)
fprintf (syn68k_c_stream, "DEREF(%s, SYN68K_TO_US (CLEAN (",
ctypes[t->u.derefinfo.sgnd][t->u.derefinfo.size]);
else
fprintf (syn68k_c_stream,
"READ%cL_UNSWAPPED ((CLEAN (",
t->u.derefinfo.sgnd ? 'S' : 'U');
generate_code_for_list (ls->cdr, m68kop, info, var);
fputs ("))) ", syn68k_c_stream);
}
}
break;
case TOK_FUNC_CALL:
if (ls->cdr == NULL || ls->cdr->token.type != TOK_QUOTED_STRING)
{
parse_error (ls, "\"call\" must be followed by a function name "
"in quotes.\n");
}
else
{
List *l2;
fprintf (syn68k_c_stream, "%s (", ls->cdr->token.u.string);
for (l2 = CDDR (ls); l2 != NULL; l2 = l2->cdr)
{
generate_code_for_list (l2, m68kop, info, var);
if (l2->cdr != NULL)
fputs (", ", syn68k_c_stream);
}
fputs (") ", syn68k_c_stream);
}
break;
/* Skip NOPs, however they were introduced. */
case TOK_NOP:
break;
default:
parse_error (ls, "Unknown operator for code list: %s\n",
unparse_token (&ls->token, buf));
break;
}
break;
/* Skip NOPs, however they were introduced. */
case TOK_NOP:
break;
case TOK_TRUE:
fputs ("1 ", syn68k_c_stream);
break;
case TOK_FALSE:
fputs ("0 ", syn68k_c_stream);
break;
case TOK_CODE:
fputs ("code ", syn68k_c_stream);
break;
case TOK_DOLLAR_DATA_REGISTER:
{
Token temp = *t;
/* Compensate for gcc i386 brain damage. */
fprintf (syn68k_c_stream, "DATA_REGISTER_%c%c (",
t->u.dollarinfo.sgnd ? 'S' : 'U',
"?BW?L"[t->u.dollarinfo.size]);
t->type = TOK_DOLLAR_NUMBER;
t->u.dollarinfo.sgnd = FALSE;
t->u.dollarinfo.size = 4;
generate_code_for_list (ls, m68kop, info, var);
*t = temp;
fputs (") ", syn68k_c_stream);
}
break;
case TOK_DOLLAR_ADDRESS_REGISTER:
{
Token temp = *t;
fprintf (syn68k_c_stream, "ADDRESS_REGISTER_%c%c ( ",
t->u.dollarinfo.sgnd ? 'S' : 'U',
"?BW?L"[t->u.dollarinfo.size]);
t->type = TOK_DOLLAR_NUMBER;
t->u.dollarinfo.sgnd = FALSE;
t->u.dollarinfo.size = 4;
generate_code_for_list (ls, m68kop, info, var);
*t = temp;
fputs (") ", syn68k_c_stream);
}
break;
case TOK_DOLLAR_GENERAL_REGISTER:
{
Token temp = *t;
fprintf (syn68k_c_stream, "GENERAL_REGISTER_%c%c (",
t->u.dollarinfo.sgnd ? 'S' : 'U',
"?BW?L"[t->u.dollarinfo.size]);
t->type = TOK_DOLLAR_NUMBER;
t->u.dollarinfo.sgnd = FALSE;
t->u.dollarinfo.size = 4;
generate_code_for_list (ls, m68kop, info, var);
*t = temp;
fputs (") ", syn68k_c_stream);
}
break;
case TOK_TEMP_REGISTER:
fprintf (syn68k_c_stream, "tmp%d%s ", t->u.reginfo.which,
regdesc[t->u.reginfo.sgnd][t->u.reginfo.size]);
break;
case TOK_DATA_REGISTER:
fprintf (syn68k_c_stream, "DATA_REGISTER_%c%c (%d) ",
t->u.dollarinfo.sgnd ? 'S' : 'U',
"?BW?L"[t->u.dollarinfo.size],
t->u.reginfo.which);
break;
case TOK_ADDRESS_REGISTER:
fprintf (syn68k_c_stream, "ADDRESS_REGISTER_%c%c (%d) ",
t->u.dollarinfo.sgnd ? 'S' : 'U',
"?BW?L"[t->u.dollarinfo.size],
t->u.reginfo.which);
break;
case TOK_AMODE_PTR:
case TOK_REVERSED_AMODE_PTR:
fputs ("(US_TO_SYN68K (", syn68k_c_stream);
output_c_for_amode_ptr (t, (t->type == TOK_REVERSED_AMODE_PTR));
fputs ("))", syn68k_c_stream);
break;
case TOK_AMODE:
case TOK_REVERSED_AMODE:
if (t->u.dollarinfo.size != 4)
{
fprintf (syn68k_c_stream, "DEREF(%s, CLEAN (",
ctypes[t->u.dollarinfo.sgnd][t->u.dollarinfo.size]);
output_c_for_amode_ptr (t, (t->type == TOK_REVERSED_AMODE));
fputs (")) ", syn68k_c_stream);
}
else
{
#if 0
fputs ("\n"
"#ifdef QUADALIGN\n"
"# ifdef BIGENDIAN\n", syn68k_c_stream);
fprintf (syn68k_c_stream, "((%s) (((((uint16 *) CLEAN (",
ctypes[t->u.dollarinfo.sgnd][t->u.dollarinfo.size]);
output_c_for_amode_ptr (t, (t->type == TOK_REVERSED_AMODE));
fputs ("))[0]) << 16) | (((uint16 *) CLEAN (", syn68k_c_stream);
output_c_for_amode_ptr (t, (t->type == TOK_REVERSED_AMODE));
fputs ("))[1])))\n", syn68k_c_stream);
fputs ("# else\n", syn68k_c_stream);
fprintf (syn68k_c_stream, "((%s) ((((uint16 *) CLEAN (",
ctypes[t->u.dollarinfo.sgnd][t->u.dollarinfo.size]);
output_c_for_amode_ptr (t, (t->type == TOK_REVERSED_AMODE));
fputs ("))[0]) | ((((uint16 *) CLEAN (", syn68k_c_stream);
output_c_for_amode_ptr (t, (t->type == TOK_REVERSED_AMODE));
fputs ("))[1]) << 16)))\n", syn68k_c_stream);
fputs ("# endif\n"
"#else\n", syn68k_c_stream);
fprintf (syn68k_c_stream, "(*(%s *) CLEAN (",
ctypes[t->u.dollarinfo.sgnd][t->u.dollarinfo.size]);
output_c_for_amode_ptr (t, (t->type == TOK_REVERSED_AMODE));
fputs (")) ", syn68k_c_stream);
fputs ("\n#endif\n", syn68k_c_stream);
#else
fprintf (syn68k_c_stream, "READ%cL_UNSWAPPED (CLEAN",
t->u.dollarinfo.sgnd ? 'S' : 'U');
output_c_for_amode_ptr (t, (t->type == TOK_REVERSED_AMODE));
fputs (") ", syn68k_c_stream);
#endif
}
break;
case TOK_NUMBER:
if (t->u.n >= 100 || t->u.n <= -100)
fprintf (syn68k_c_stream, "((int32) 0x%lX) ", (unsigned long)t->u.n);
else fprintf (syn68k_c_stream, "%ld ", t->u.n);
break;
/* Pass quoted strings on to the C compiler. */
case TOK_QUOTED_STRING:
fprintf (syn68k_c_stream, "%s ", t->u.string); /* Append a space. */
break;
case TOK_CCC: fputs ("cpu_state.ccc ", syn68k_c_stream); break;
case TOK_CCN: fputs ("cpu_state.ccn ", syn68k_c_stream); break;
case TOK_CCV: fputs ("cpu_state.ccv ", syn68k_c_stream); break;
case TOK_CCX: fputs ("cpu_state.ccx ", syn68k_c_stream); break;
case TOK_CCNZ: fputs ("cpu_state.ccnz ", syn68k_c_stream); break;
/* If we still haven't been able to resolve the addressing mode,
* a pointer to the data should have been put in the appropriate
* local variable by a preceding instruction.
*/
case TOK_DOLLAR_AMODE:
if (t->u.dollarinfo.size != 4)
fprintf (syn68k_c_stream, "DEREF(%s, cpu_state.amode_p) ",
ctypes[t->u.dollarinfo.sgnd][t->u.dollarinfo.size]);
else
fprintf (syn68k_c_stream, "READ%cL_UNSWAPPED ( US_TO_SYN68K (cpu_state.amode_p)) ",
t->u.dollarinfo.sgnd ? 'S' : 'U');
break;
case TOK_DOLLAR_REVERSED_AMODE:
if (t->u.dollarinfo.size != 4)
fprintf (syn68k_c_stream, "DEREF(%s, cpu_state.reversed_amode_p) ",
ctypes[t->u.dollarinfo.sgnd][t->u.dollarinfo.size]);
else
fprintf (syn68k_c_stream,
"READ%cL_UNSWAPPED ( US_TO_SYN68K (cpu_state.reversed_amode_p)) ",
t->u.dollarinfo.sgnd ? 'S' : 'U');
break;
case TOK_DOLLAR_AMODE_PTR:
fprintf (syn68k_c_stream, "US_TO_SYN68K (cpu_state.amode_p) ");
break;
case TOK_DOLLAR_REVERSED_AMODE_PTR:
fprintf (syn68k_c_stream, "US_TO_SYN68K (cpu_state.reversed_amode_p) ");
break;
case TOK_DOLLAR_NUMBER:
#if 1 || !defined(TEMPS_AT_TOP)
fprintf (syn68k_c_stream, "operand_%d ", t->u.dollarinfo.which);
#else /* defined(TEMPS_AT_TOP) */
fprintf (syn68k_c_stream, "operand_%s%d_%d ",
t->u.dollarinfo.sgnd ? "" : "u",
t->u.dollarinfo.size*8, t->u.dollarinfo.which);
#endif /* defined(TEMPS_AT_TOP) */
break;
default:
parse_error (ls, "Unknown code element: %s\n", unparse_token (t, buf));
break;
}
}
/* Writes out a human readable string describing a set of cc bits into buf.
* For example, "11001" becomes "CN--Z" (the cc bits are in alphabetical
* order). Returns buf.
*/
static char *
cc_bits_string (int bits, char *buf)
{
int i;
/* Generate the string. */
for (i = 0; i < 5; i++)
buf[i] = (bits & (1 << (4 - i))) ? "CNVXZ"[i] : '-';
buf[5] = '\0';
return buf;
}
/* Generates a string describing what bits were expanded for this particular
* CC variant of this opcode.
*/
static char *
opcode_bits_string (int bits, const ParsedOpcodeInfo *info,
const CCVariant *var, char *buf)
{
const char *p, *i = info->opcode_bits;
char *b = buf;
int mask;
/* Generate the string. */
for (mask = 1 << 15, p = var->bits_to_expand; mask != 0; i++,p++, mask >>= 1)
*b++ = ((*p == '-' && *i != '0' && *i != '1')
? '-' : ((bits & mask) ? '1' : '0'));
buf[16] = '\0';
return buf;
}
/* Helper function; takes an operator string, like "+" or "&&" and a list
* of expressions and outputs c code: (expr1 op expr2 op expr3 op ... exprn)
*/
static void
binary_op_list (const char *op, List *ls, int m68kop,
const ParsedOpcodeInfo *info, const CCVariant *var)
{
putc ('(', syn68k_c_stream);
/* Output something for empty list. */
if (ls == NULL)
fputs ("0 ", syn68k_c_stream);
for (; ls != NULL; ls = ls->cdr)
{
generate_code_for_list (ls, m68kop, info, var);
if (ls->cdr != NULL)
fprintf (syn68k_c_stream, "%s ", op);
}
putc (')', syn68k_c_stream);
}
/* Recursive helper function for replace_dollar_elements(). */
static void
rde_aux (List *code, const PatternRange *ranges, int m68kop,
const ParsedOpcodeInfo *info, const CCVariant *var, int expand_mask)
{
Token *t;
/* Base case: NULL list. */
if (code == NULL)
return;
/* If we find a $ identifier, replace it with the appropriate expression. */
t = &code->token;
if (IS_DOLLAR_TOKEN (t->type))
{
int index, length;
BOOL is_constant = FALSE;
int constant;
/* Fetch the bit range of that field. */
index = ranges[t->u.dollarinfo.which].index;
length = ranges[t->u.dollarinfo.which].length;
/* See if this collapses to a known constant. */
if (index + length <= 16)
{
int i;
/* Grab the constant and see if it's legitimate. */
constant = 0;
is_constant = TRUE;
for (i = 0; i < length; i++)
{
if (var->bits_to_expand[i + index] == '-')
{
is_constant = FALSE;
break;
}
else if (m68kop & ((1 << (15 - index)) >> i))
constant |= (1 << (length - 1)) >> i;
}
}
else
constant = 0; /* To avoid compiler warnings. */
if (is_constant)
handle_constant_dollar_field (code, constant, length);
else
{
}
}
/* Recurse on the rest of the list. */
rde_aux (code->car, ranges, m68kop, info, var, expand_mask);
rde_aux (code->cdr, ranges, m68kop, info, var, expand_mask);
}
/* Replaces all of the dollar elements with non-dollar expressions. */
static List *
replace_dollar_elements (List *code, int m68kop, const ParsedOpcodeInfo *info,
const CCVariant *var)
{
int i, expand_mask = 0;
PatternRange ranges[32];
/* Compute the mask for the bits we are expanding. */
for (i = 0; i < 16; i++)
if (var->bits_to_expand[15 - i] != '-')
expand_mask = (1 << i);
/* Compute the field ranges for all of the fields. */
for (i = 1; pattern_range (info->opcode_bits, i, &ranges[i]); i++)
;
/* Recursively replace all of the $ identifiers with expressions. */
rde_aux (code, ranges, m68kop, info, var, expand_mask);
return code;
}
static void
handle_constant_dollar_field (List *ls, int constant, int field_length)
{
Token *t = &ls->token;
Token copy_of_t = *t;
/* Switch on what type of argument this is. */
switch (t->type) {
/* Data register. */
case TOK_DOLLAR_DATA_REGISTER:
t->type = TOK_DATA_REGISTER;
t->u.reginfo.which = constant;
t->u.reginfo.sgnd = copy_of_t.u.dollarinfo.sgnd;
t->u.reginfo.size = copy_of_t.u.dollarinfo.size;
break;
/* Address register. */
case TOK_DOLLAR_ADDRESS_REGISTER:
t->type = TOK_ADDRESS_REGISTER;
t->u.reginfo.which = constant;
t->u.reginfo.sgnd = copy_of_t.u.dollarinfo.sgnd;
t->u.reginfo.size = copy_of_t.u.dollarinfo.size;
break;
/* General register. */
case TOK_DOLLAR_GENERAL_REGISTER:
t->type = (constant >= 8 ? TOK_ADDRESS_REGISTER : TOK_DATA_REGISTER);
t->u.reginfo.which = constant % 8;
t->u.reginfo.sgnd = copy_of_t.u.dollarinfo.sgnd;
t->u.reginfo.size = copy_of_t.u.dollarinfo.size;
break;
case TOK_DOLLAR_AMODE:
if (((constant >> 3) & 7) == 0)
{
t->type = TOK_DATA_REGISTER;
t->u.reginfo.which = constant & 7;
t->u.reginfo.sgnd = copy_of_t.u.dollarinfo.sgnd;
t->u.reginfo.size = copy_of_t.u.dollarinfo.size;
}
else if (((constant >> 3) & 7) == 1)
{
t->type = TOK_ADDRESS_REGISTER;
t->u.reginfo.which = constant & 7;
t->u.reginfo.sgnd = copy_of_t.u.dollarinfo.sgnd;
t->u.reginfo.size = copy_of_t.u.dollarinfo.size;
}
else
{
t->type = TOK_AMODE;
t->u.amodeinfo.which = constant;
t->u.amodeinfo.sgnd = copy_of_t.u.dollarinfo.sgnd;
t->u.amodeinfo.size = copy_of_t.u.dollarinfo.size;
}
break;
case TOK_DOLLAR_REVERSED_AMODE:
if ((constant & 7) == 0)
{
t->type = TOK_DATA_REGISTER;
t->u.reginfo.which = constant & 7;
t->u.reginfo.sgnd = copy_of_t.u.dollarinfo.sgnd;
t->u.reginfo.size = copy_of_t.u.dollarinfo.size;
}
else if ((constant & 7) == 1)
{
t->type = TOK_ADDRESS_REGISTER;
t->u.reginfo.which = constant & 7;
t->u.reginfo.sgnd = copy_of_t.u.dollarinfo.sgnd;
t->u.reginfo.size = copy_of_t.u.dollarinfo.size;
}
else
{
t->type = TOK_REVERSED_AMODE; /* We swap the bits here anyway. */
t->u.amodeinfo.which = ((constant & 7) << 3) | ((constant >> 3) & 7);
t->u.amodeinfo.sgnd = copy_of_t.u.dollarinfo.sgnd;
t->u.amodeinfo.size = copy_of_t.u.dollarinfo.size;
}
break;
case TOK_DOLLAR_NUMBER:
t->type = TOK_NUMBER;
/* Sign extend if we have to. Assumes 2's complement machine. */
if (t->u.dollarinfo.sgnd && (constant & (1L << (field_length - 1))))
constant |= ~((1L << field_length) - 1);
/* Save the new, sign extended number. */
t->u.n = constant;
break;
default:
fatal_error ("Internal error: generate_code.c: IS_DOLLAR_TOKEN() "
"must be bad.\n");
break;
}
}
static void
output_c_for_amode_ptr (const Token *t, BOOL reversed)
{
int reg = t->u.amodeinfo.which & 7, mode = (t->u.amodeinfo.which >> 3) & 7;
char buf[512];
int size = t->u.amodeinfo.size;
switch (mode) {
case 0:
case 1:
fatal_error ("Internal error: called output_c_for_amode_ptr with "
"a register addressing mode!");
break;
case 2:
fprintf (syn68k_c_stream, "(ADDRESS_REGISTER_UL (%d)) ", reg);
break;
case 3:
fprintf (syn68k_c_stream, "(ADDRESS_REGISTER_UL (%d)) ", reg);
/* Perform postincrement, but force sp to remain even! */
if (size == 1 && reg != 7)
sprintf (buf, "++ADDRESS_REGISTER_UL (%d); ", reg);
else
sprintf (buf, "INC_VAR (ADDRESS_REGISTER_UL (%d), %d); ", reg,
(reg != 7 || size != 1) ? size : 2);
if (strstr (c_postamble, buf) == NULL)
strcat (c_postamble, buf);
break;
case 4:
fprintf (syn68k_c_stream, "(ADDRESS_REGISTER_UL (%d) - %d) ", reg,
(reg != 7 || size != 1) ? size : 2);
/* Perform predecrement, but force sp to remain even! */
if (size == 1 && reg != 7)
sprintf (buf, "--ADDRESS_REGISTER_UL (%d); ", reg);
else
sprintf (buf, "DEC_VAR (ADDRESS_REGISTER_UL (%d), %d); ", reg,
(reg != 7 || size != 1) ? size : 2);
if (strstr (c_postamble, buf) == NULL)
strcat (c_postamble, buf);
break;
case 5:
fatal_error ("Internal error: attempting to generate code for fixed "
"amode 5. It should have been expanded and replaced with "
"explicit code to compute the pointer.\n");
break;
/* Modes 6 and 7 are too complicated to expand; a pointer to the data
* will be placed in the appropriate place by the synthetic instruction
* right before this one.
*/
case 6:
case 7:
if (!reversed)
fprintf (syn68k_c_stream, "US_TO_SYN68K (cpu_state.amode_p) ");
else
fprintf (syn68k_c_stream, "US_TO_SYN68K (cpu_state.reversed_amode_p) ");
break;
}
}
/* Helper function for generate_temp_decls, below. */
static void
gtd_aux (List *code, BOOL *decld, BOOL *any_so_far)
{
Token *t;
if (code == NULL)
return;
t = &code->token;
if (t->type == TOK_TEMP_REGISTER)
{
if (!decld[t->u.reginfo.which])
{
if (!*any_so_far)
{
fputs (" M68kReg", syn68k_c_stream);
*any_so_far = TRUE;
}
else
putc (',', syn68k_c_stream);
fprintf (syn68k_c_stream, " tmp%d", t->u.reginfo.which);
decld[t->u.reginfo.which] = TRUE;
}
}
gtd_aux (code->car, decld, any_so_far);
gtd_aux (code->cdr, decld, any_so_far);
}
/* This generates local declarations for all of the temp variables we
* actually use. We declare a new set for each case statement to help
* the compiler identify dead variables.
*/
static void
generate_temp_decls (List *code)
{
#if !defined(TEMPS_AT_TOP)
BOOL decld[128];
BOOL found = FALSE;
memset (decld, 0, sizeof decld);
gtd_aux (code, decld, &found);
if (found)
fputs (";\n", syn68k_c_stream);
#endif
}
/* Helper function for transform_rtvad_aux, below. This replaces all
* instances of a given temp register with a TOK_QUOTED_STRING containing
* the name of the C variable that is replacing it.
*/
static void
transform_reg_to_var (List *code, Token *to_replace, const char *var_name)
{
/* Recursion base case. */
if (code == NULL)
return;
/* If this is the appropriate temp register, replace it. */
if (tokens_equal (&code->token, to_replace))
{
code->token.type = TOK_QUOTED_STRING;
code->token.u.string = var_name;
}
/* Recurse. */
transform_reg_to_var (code->car, to_replace, var_name);
transform_reg_to_var (code->cdr, to_replace, var_name);
}
/* Helper function for transform_rtvad_aux, below. This function takes
* an example usage of a given temp register, and determines whether every
* other usage of that temp register is of the same form. For example,
* for (assign foo (+ tmp2.ub tmp2.ub)) this would return TRUE,
* but for (assign foo (+ tmp2.ub tmp2.sl)) this would return FALSE.
*/
static BOOL
temp_use_consistent (List *code, Token *one_use)
{
Token *t;
/* Recursion base case. */
if (code == NULL)
return TRUE;
/* If this is a usage of the specified temp reg, see if it is used in
* the same way as ONE_USE.
*/
t = &code->token;
if (t->type == TOK_TEMP_REGISTER
&& t->u.reginfo.which == one_use->u.reginfo.which)
{
if (t->u.reginfo.sgnd != one_use->u.reginfo.sgnd
|| t->u.reginfo.size != one_use->u.reginfo.size)
return FALSE;
}
/* Recurse. */
return (temp_use_consistent (code->car, one_use)
&& temp_use_consistent (code->cdr, one_use));
}
/* Helper function for transform_reg_to_var_and_decl, below. This
* recurses over all of the code and determines when it can replace
* a given temp register with a variable of a simpler C type.
*/
static void
transform_rtvad_aux (List *root, List *code, char decls[2][5][1024])
{
Token *t;
/* Recursion base case. */
if (code == NULL)
return;
t = &code->token;
if (t->type == TOK_TEMP_REGISTER && temp_use_consistent (root, t))
{
char buf[128], *s = decls[t->u.reginfo.sgnd][t->u.reginfo.size];
const char *name;
Token copy_of_t = *t;
/* Choose a descriptive + unique name for this new temp variable. */
sprintf (buf, "tmp%c%c%d", t->u.reginfo.sgnd ? 's' : 'u',
"?bw?l"[t->u.reginfo.size], t->u.reginfo.which);
name = unique_string (buf);
/* Add this variable's name to the list of variables of this type
* to declare.
*/
if (s[0] != '\0') /* Add a comma if there are previous decls. */
strcat (s, ",");
sprintf (s + strlen (s), " %s", name);
/* Replace all occurrences of this temp register with the temp
* variable we just made.
*/
transform_reg_to_var (root, &copy_of_t, name);
}
/* Recurse on the rest of the code. */
transform_rtvad_aux (root, code->car, decls);
transform_rtvad_aux (root, code->cdr, decls);
}
/* This function simplifies TEMP_REGISTERs that are only used in one way
* by transforming them from the complex union they normally comprise to
* a simple C type. For example, if "tmp2" is only used as "tmp2.ub" in the
* entire scope of its lifetime, we can replace it with a variable of
* type "uint8". This should help the compiler and make syn68k.c somewhat
* easier to read.
*/
static void
transform_reg_to_var_and_decl (List *code)
{
#if !defined(TEMPS_AT_TOP)
char decls[2][5][1024]; /* decls[signed][byte size][variable names] */
int sgnd, i;
/* Clear out all decls. */
for (i = 0; i < 5; i++)
decls[0][i][0] = decls[1][i][0] = '\0';
/* Recursively make all the transformations and declarations. */
transform_rtvad_aux (code, code, decls);
/* Loop through and output decls for each variable type that we use. */
for (sgnd = 0; sgnd <= 1; sgnd++)
for (i = 1; i < 5; i++)
{
if (decls[sgnd][i][0] != '\0')
fprintf (syn68k_c_stream, " %s%s;\n", ctypes[sgnd][i],
decls[sgnd][i]);
}
#endif
}