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- /* $Header$ */
- /* EXPRESSION-CODE GENERATOR */
- /* main functions :
- EVAL() -- expression tree evaluator
- tmp_pointer_var() -- deliver temporary pointer variable
- free_tmp_var() -- return the pointer var
- store_val() -- store primary expression
- load_val() -- load primary expression
- auxiliary functions:
- assop()
- compare()
- */
- #include <em.h>
- #include "debug.h"
- #include "nobitfield.h"
- #include "dataflow.h"
- #include "arith.h"
- #include "type.h"
- #include "idf.h"
- #include "label.h"
- #include "code.h"
- #include "assert.h"
- #include "def.h"
- #include "expr.h"
- #include "sizes.h"
- #include "Lpars.h"
- #include "level.h"
- #include "stack.h"
- #include "align.h"
- #include "mes.h"
- #include "atw.h"
- #define CRASH() crash("EVAL: CRASH at line %u", __LINE__)
- #define roundup(n) ((n) < word_size ? word_size : (n))
- char *symbol2str();
- char *long2str();
- arith tmp_pointer_var();
- /* EVAL() serves as the main expression tree evaluator, which turns
- any legal expression tree into legal EM code.
- The parameters describe how EVAL should treat the expression tree:
- struct expr *expr: pointer to root of the expression tree to
- be evaluated
- int val: indicates whether the resulting expression
- is to be dereferenced (if val == RVAL and
- expr->ex_lvalue == 1) or not (val == LVAL).
- The latter case indicates that the resulting
- expression is an lvalue expression which should
- not be dereferenced by EVAL
-
- int code: indicates whether the expression tree must be
- turned into EM code or not. E.g. the expression
- statement "12;" delivers the expression "12" to
- EVAL while this should not result in any EM
- code
-
- label false_label:
- label true_label: if the expression is a logical or relational
- expression and if the loop of the program
- depends on the resulting value then EVAL
- generates jumps to the specified program
- labels, in case they are specified
- (i.e. are non-zero)
- */
- EVAL(expr, val, code, true_label, false_label)
- struct expr *expr; /* the expression tree itself */
- int val; /* either RVAL or LVAL */
- int code; /* generate explicit code or not */
- label true_label;
- label false_label; /* labels to jump to in logical expr's */
- {
- register gencode = (code == TRUE);
- switch (expr->ex_class) {
- case Value: /* just a simple value */
- if (gencode)
- load_val(expr, val);
- break;
- case String: /* a string constant */
- if (gencode) {
- label datlab = data_label();
-
- C_df_dlb(datlab);
- C_con_scon(expr->SG_VALUE, (arith)expr->SG_LEN);
- C_lae_dlb(datlab, (arith)0);
- }
- break;
- case Float: /* a floating constant */
- if (gencode) {
- label datlab = data_label();
-
- C_df_dlb(datlab);
- C_rom_fcon(expr->FL_VALUE, expr->ex_type->tp_size);
- C_lae_dlb(datlab, (arith)0);
- C_loi(expr->ex_type->tp_size);
- }
- break;
- case Oper: /* compound expression */
- {
- register int oper = expr->OP_OPER;
- register struct expr *leftop = expr->OP_LEFT;
- register struct expr *rightop = expr->OP_RIGHT;
- register struct type *tp = expr->OP_TYPE;
- if (tp->tp_fund == ERRONEOUS) /* stop immediately */
- break;
- switch (oper) {
- case '+':
- /* We have the following possibilities :
- int + int, pointer + int, pointer + long,
- long + long, double + double
- */
- EVAL(leftop, RVAL, code, NO_LABEL, NO_LABEL);
- EVAL(rightop, RVAL, code, NO_LABEL, NO_LABEL);
- if (gencode) {
- switch (tp->tp_fund) {
- case INT:
- case LONG:
- if (tp->tp_unsigned)
- C_adu(tp->tp_size);
- else
- C_adi(tp->tp_size);
- break;
- case POINTER:
- C_ads(rightop->ex_type->tp_size);
- break;
- case DOUBLE:
- C_adf(tp->tp_size);
- break;
- default:
- crash("bad type +");
- }
- }
- break;
- case '-':
- if (leftop == 0) { /* unary */
- EVAL(rightop, RVAL, code, NO_LABEL, NO_LABEL);
- if (gencode) {
- switch (tp->tp_fund) {
- case DOUBLE:
- C_ngf(tp->tp_size);
- break;
- case INT:
- case LONG:
- case POINTER:
- C_ngi(tp->tp_size);
- break;
- default:
- CRASH();
- }
- }
- break;
- }
- /* Binary: we have the following flavours:
- int - int, pointer - int, pointer - long,
- pointer - pointer, long - long, double - double
- */
- EVAL(leftop, RVAL, code, NO_LABEL, NO_LABEL);
- EVAL(rightop, RVAL, code, NO_LABEL, NO_LABEL);
- if (!gencode)
- break;
- switch (tp->tp_fund) {
- case INT:
- case LONG:
- if (tp->tp_unsigned)
- C_sbu(tp->tp_size);
- else
- C_sbi(tp->tp_size);
- break;
- case POINTER:
- if (rightop->ex_type->tp_fund == POINTER)
- C_sbs(pointer_size);
- else {
- C_ngi(rightop->ex_type->tp_size);
- C_ads(rightop->ex_type->tp_size);
- }
- break;
- case DOUBLE:
- C_sbf(tp->tp_size);
- break;
- default:
- crash("bad type -");
- }
- break;
- case '*':
- if (leftop == 0) /* unary */
- EVAL(rightop, RVAL, code, NO_LABEL, NO_LABEL);
- else { /* binary */
- EVAL(leftop, RVAL, code, NO_LABEL, NO_LABEL);
- EVAL(rightop, RVAL, code, NO_LABEL, NO_LABEL);
- if (gencode)
- switch (tp->tp_fund) {
- case INT:
- case LONG:
- case POINTER:
- if (tp->tp_unsigned)
- C_mlu(tp->tp_size);
- else
- C_mli(tp->tp_size);
- break;
- case DOUBLE:
- C_mlf(double_size);
- break;
- default:
- crash("bad type *");
- }
- }
- break;
- case '/':
- EVAL(leftop, RVAL, code, NO_LABEL, NO_LABEL);
- EVAL(rightop, RVAL, code, NO_LABEL, NO_LABEL);
- if (gencode)
- switch (tp->tp_fund) {
- case INT:
- case LONG:
- case POINTER:
- if (tp->tp_unsigned)
- C_dvu(tp->tp_size);
- else
- C_dvi(tp->tp_size);
- break;
- case DOUBLE:
- C_dvf(double_size);
- break;
- default:
- crash("bad type /");
- }
- break;
- case '%':
- EVAL(leftop, RVAL, code, NO_LABEL, NO_LABEL);
- EVAL(rightop, RVAL, code, NO_LABEL, NO_LABEL);
- if (gencode)
- if ( tp->tp_fund == INT
- || tp->tp_fund == LONG
- ) {
- if (tp->tp_unsigned)
- C_rmu(tp->tp_size);
- else
- C_rmi(tp->tp_size);
- }
- else
- crash("bad type %%");
- break;
- case LEFT:
- EVAL(leftop, RVAL, code, NO_LABEL, NO_LABEL);
- EVAL(rightop, RVAL, code, NO_LABEL, NO_LABEL);
- if (gencode)
- if (tp->tp_unsigned)
- C_slu(tp->tp_size);
- else
- C_sli(tp->tp_size);
- break;
- case RIGHT:
- EVAL(leftop, RVAL, code, NO_LABEL, NO_LABEL);
- EVAL(rightop, RVAL, code, NO_LABEL, NO_LABEL);
- if (gencode)
- if (tp->tp_unsigned)
- C_sru(tp->tp_size);
- else
- C_sri(tp->tp_size);
- break;
- case '<':
- case LESSEQ:
- case '>':
- case GREATEREQ:
- case EQUAL:
- case NOTEQUAL:
- EVAL(leftop, RVAL, code, NO_LABEL, NO_LABEL);
- EVAL(rightop, RVAL, code, NO_LABEL, NO_LABEL);
- if (gencode) {
- /* The operands have the same type */
- arith size = leftop->ex_type->tp_size;
-
- switch (tp->tp_fund) {
- case INT:
- case LONG:
- if (leftop->ex_type->tp_unsigned)
- C_cmu(size);
- else
- C_cmi(size);
- break;
- case FLOAT:
- case DOUBLE:
- C_cmf(size);
- break;
- case POINTER:
- C_cmp();
- break;
- case ENUM:
- C_cmi(size);
- break;
- default:
- CRASH();
- }
- if (true_label != 0) {
- compare(oper, true_label);
- C_bra(false_label);
- }
- else {
- label l_true = text_label();
- label l_end = text_label();
- compare(oper, l_true);
- C_loc((arith)0);
- C_bra(l_end);
- C_df_ilb(l_true);
- C_loc((arith)1);
- C_df_ilb(l_end);
- }
- }
- break;
- case '&':
- case '|':
- case '^':
- /* both operands should have type int */
- EVAL(leftop, RVAL, code, NO_LABEL, NO_LABEL);
- EVAL(rightop, RVAL, code, NO_LABEL, NO_LABEL);
- if (gencode) {
- arith size = tp->tp_size;
- if (size < word_size)
- size = word_size;
- switch (oper) {
- case '&':
- C_and(size);
- break;
- case '|':
- C_ior(size);
- break;
- case '^':
- C_xor(size);
- break;
- }
- }
- break;
- case '=':
- #ifndef NOBITFIELD
- if (leftop->ex_type->tp_fund == FIELD) {
- /* assignment to bitfield variable
- */
- eval_field(expr, code);
- break;
- }
- #endif NOBITFIELD
- EVAL(rightop, RVAL, TRUE, NO_LABEL, NO_LABEL);
- if (gencode)
- C_dup(ATW(tp->tp_size));
- if (leftop->ex_class != Value) {
- EVAL(leftop, LVAL, TRUE, NO_LABEL, NO_LABEL);
- store_block(tp->tp_size, tp->tp_align);
- }
- else
- store_val(leftop->VL_IDF, leftop->ex_type,
- leftop->VL_VALUE);
- break;
- case PLUSAB:
- case MINAB:
- case TIMESAB:
- case DIVAB:
- case MODAB:
- case LEFTAB:
- case RIGHTAB:
- case ANDAB:
- case XORAB:
- case ORAB:
- #ifndef NOBITFIELD
- if (leftop->ex_type->tp_fund == FIELD) {
- eval_field(expr, code);
- break;
- }
- #endif NOBITFIELD
- if (leftop->ex_class != Value) {
- arith old_offset;
- arith tmpvar = tmp_pointer_var(&old_offset);
- EVAL(leftop, LVAL, TRUE, NO_LABEL, NO_LABEL);
- C_lal(tmpvar);
- C_sti(pointer_size);
- C_lal(tmpvar);
- C_loi(pointer_size);
- C_loi(tp->tp_size);
- EVAL(rightop, RVAL, TRUE, NO_LABEL, NO_LABEL);
- assop(tp, oper);
- if (gencode)
- C_dup(roundup(tp->tp_size));
- C_lal(tmpvar);
- C_loi(pointer_size);
- C_sti(tp->tp_size);
- free_tmp_var(old_offset);
- }
- else {
- load_val(leftop, RVAL);
- EVAL(rightop, RVAL, TRUE, NO_LABEL, NO_LABEL);
- assop(tp, oper);
- if (gencode)
- C_dup(roundup(tp->tp_size));
- store_val(leftop->VL_IDF, leftop->ex_type,
- leftop->VL_VALUE);
- }
- break;
- case '(':
- {
- register struct expr *expr;
- arith ParSize = (arith)0;
- if (expr = rightop) {
- /* function call with parameters*/
- while ( expr->ex_class == Oper &&
- expr->OP_OPER == PARCOMMA
- ) {
- EVAL(expr->OP_RIGHT, RVAL, TRUE,
- NO_LABEL, NO_LABEL);
- ParSize +=
- ATW(expr->ex_type->tp_size);
- expr = expr->OP_LEFT;
- }
- EVAL(expr, RVAL, TRUE, NO_LABEL, NO_LABEL);
- ParSize += ATW(expr->ex_type->tp_size);
- }
- if (leftop->ex_class == Value && leftop->VL_IDF != 0) {
- /* just an example:
- main() { (*((int (*)())0))(); }
- */
- C_cal(leftop->VL_IDF->id_text);
- #ifdef DATAFLOW
- { extern char options[];
- if (options['d'])
- DfaCallFunction(
- leftop->VL_IDF->id_text
- );
- }
- #endif DATAFLOW
- }
- else {
- EVAL(leftop, LVAL, TRUE, NO_LABEL, NO_LABEL);
- C_cai();
- }
- /* remove parameters from stack */
- if (ParSize > (arith)0)
- C_asp(ParSize);
- if (!gencode)
- break;
- if (is_struct_or_union(tp->tp_fund)) {
- C_lfr(pointer_size);
- load_block(tp->tp_size, tp->tp_align);
- }
- else
- C_lfr(ATW(tp->tp_size));
- break;
- }
- case '.':
- EVAL(leftop, LVAL, code, NO_LABEL, NO_LABEL);
- if (gencode)
- C_adp(rightop->VL_VALUE);
- break;
- case ARROW:
- EVAL(leftop, RVAL, code, NO_LABEL, NO_LABEL);
- if (gencode)
- C_adp(rightop->VL_VALUE);
- break;
- case ',':
- EVAL(leftop, RVAL, FALSE, NO_LABEL, NO_LABEL);
- EVAL(rightop, RVAL, code, NO_LABEL, NO_LABEL);
- break;
- case '~':
- EVAL(rightop, RVAL, code, NO_LABEL, NO_LABEL);
- if (gencode)
- C_com(tp->tp_size);
- break;
- case POSTINCR:
- case POSTDECR:
- case PLUSPLUS:
- case MINMIN:
- {
- arith old_offset, tmp;
- arith esize = tp->tp_size;
- #ifndef NOBITFIELD
- if (leftop->ex_type->tp_fund == FIELD) {
- eval_field(expr, code);
- break;
- }
- #endif NOBITFIELD
- if (leftop->ex_class != Value) {
- tmp = tmp_pointer_var(&old_offset);
- EVAL(leftop, LVAL, TRUE, NO_LABEL, NO_LABEL);
- C_dup(pointer_size);
- C_lal(tmp);
- C_sti(pointer_size);
- C_loi(tp->tp_size);
- }
- else
- load_val(leftop, RVAL);
- /* We made the choice to put this stuff here
- and not to put the conversion in the expression
- tree because this conversion is EM dependent
- and not described in C
- */
- if (esize < word_size) {
- conversion(tp, word_type);
- esize = word_size;
- }
- if (gencode && (oper == POSTINCR || oper == POSTDECR))
- C_dup(esize);
- EVAL(rightop, RVAL, TRUE, NO_LABEL, NO_LABEL);
- assop(tp, oper);
- if (gencode && (oper == PLUSPLUS || oper == MINMIN))
- C_dup(esize);
- if (tp->tp_size < word_size)
- conversion(word_type, tp);
- if (leftop->ex_class != Value) {
- C_lal(tmp); /* always init'd */
- C_loi(pointer_size);
- C_sti(tp->tp_size);
- free_tmp_var(old_offset);
- }
- else
- store_val(leftop->VL_IDF, leftop->ex_type,
- leftop->VL_VALUE);
- break;
- }
- case '?': /* must be followed by ':' */
- {
- label l_true = text_label();
- label l_false = text_label();
- label l_end = text_label();
- EVAL(leftop, RVAL, TRUE, l_true, l_false);
- C_df_ilb(l_true);
- EVAL(rightop->OP_LEFT, RVAL, code,
- NO_LABEL, NO_LABEL);
- C_bra(l_end);
- C_df_ilb(l_false);
- EVAL(rightop->OP_RIGHT, RVAL, code,
- NO_LABEL, NO_LABEL);
- C_df_ilb(l_end);
- break;
- }
- case AND:
- if (true_label == 0) {
- label l_true = text_label();
- label l_false = text_label();
- label l_maybe = text_label();
- label l_end = text_label();
- EVAL(leftop, RVAL, TRUE, l_maybe, l_false);
- C_df_ilb(l_maybe);
- if (gencode) {
- EVAL(rightop, RVAL, TRUE,
- l_true, l_false);
- C_df_ilb(l_true);
- C_loc((arith)1);
- C_bra(l_end);
- C_df_ilb(l_false);
- C_loc((arith)0);
- C_df_ilb(l_end);
- }
- else {
- EVAL(rightop, RVAL, FALSE, l_false,
- l_false);
- C_df_ilb(l_false);
- }
- }
- else {
- label l_maybe = text_label();
- EVAL(leftop, RVAL, TRUE, l_maybe, false_label);
- C_df_ilb(l_maybe);
- EVAL(rightop, RVAL, code, true_label,
- false_label);
- }
- break;
- case OR:
- if (true_label == 0) {
- label l_true = text_label();
- label l_false = text_label();
- label l_maybe = text_label();
- label l_end = text_label();
- EVAL(leftop, RVAL, TRUE, l_true, l_maybe);
- C_df_ilb(l_maybe);
- if (gencode) {
- EVAL(rightop, RVAL, TRUE,
- l_true, l_false);
- C_df_ilb(l_false);
- C_loc((arith)0);
- C_bra(l_end);
- C_df_ilb(l_true);
- C_loc((arith)1);
- C_df_ilb(l_end);
- }
- else {
- EVAL(rightop, RVAL, FALSE, l_true,
- l_true);
- C_df_ilb(l_true);
- }
- }
- else {
- label l_maybe = text_label();
- EVAL(leftop, RVAL, TRUE, true_label, l_maybe);
- C_df_ilb(l_maybe);
- EVAL(rightop, RVAL, code, true_label,
- false_label);
- }
- break;
- case '!':
- if (true_label == 0) {
- if (gencode) {
- label l_true = text_label();
- label l_false = text_label();
- label l_end = text_label();
- EVAL(rightop, RVAL, TRUE,
- l_false, l_true);
- C_df_ilb(l_false);
- C_loc((arith)0);
- C_bra(l_end);
- C_df_ilb(l_true);
- C_loc((arith)1);
- C_df_ilb(l_end);
- }
- else
- EVAL(rightop, RVAL, FALSE,
- NO_LABEL, NO_LABEL);
- }
- else
- EVAL(rightop, RVAL, code, false_label,
- true_label);
- break;
- case INT2INT:
- case INT2FLOAT:
- case FLOAT2INT:
- case FLOAT2FLOAT:
- EVAL(rightop, RVAL, code, NO_LABEL, NO_LABEL);
- if (gencode)
- conversion(rightop->ex_type, leftop->ex_type);
- break;
- default:
- crash("(EVAL) bad operator %s\n", symbol2str(oper));
- }
- /* If the rvalue of the expression is required but
- only its lvalue is evaluated, its rvalue is
- loaded by the following statements:
- */
- if (gencode && val == RVAL && expr->ex_lvalue == 1)
- load_block(expr->ex_type->tp_size,
- expr->ex_type->tp_align);
- break;
- }
- case Type:
- default:
- crash("(EVAL) bad expression class");
- }
- }
- /* compare() serves as an auxiliary function of EVAL */
- compare(relop, lbl)
- int relop;
- label lbl;
- {
- switch (relop) {
- case '<':
- C_zlt(lbl);
- break;
- case LESSEQ:
- C_zle(lbl);
- break;
- case '>':
- C_zgt(lbl);
- break;
- case GREATEREQ:
- C_zge(lbl);
- break;
- case EQUAL:
- C_zeq(lbl);
- break;
- case NOTEQUAL:
- C_zne(lbl);
- break;
- default:
- CRASH();
- }
- }
- /* assop() generates the opcode of an assignment operators op= */
- assop(type, oper)
- struct type *type;
- int oper;
- {
- register arith size = type->tp_size;
- register uns = type->tp_unsigned;
- if (size < word_size)
- size = word_size;
- switch (type->tp_fund) {
- case CHAR:
- case SHORT:
- case INT:
- case LONG:
- case ENUM:
- switch (oper) {
- case PLUSAB:
- case PLUSPLUS:
- case POSTINCR:
- if (uns)
- C_adu(size);
- else
- C_adi(size);
- break;
- case MINAB:
- case MINMIN:
- case POSTDECR:
- if (uns)
- C_sbu(size);
- else
- C_sbi(size);
- break;
- case TIMESAB:
- if (uns)
- C_mlu(size);
- else
- C_mli(size);
- break;
- case DIVAB:
- if (uns)
- C_dvu(size);
- else
- C_dvi(size);
- break;
- case MODAB:
- if (uns)
- C_rmu(size);
- else
- C_rmi(size);
- break;
- case LEFTAB:
- if (uns)
- C_slu(size);
- else
- C_sli(size);
- break;
- case RIGHTAB:
- if (uns)
- C_sru(size);
- else
- C_sri(size);
- break;
- case ANDAB:
- C_and(size);
- break;
- case XORAB:
- C_xor(size);
- break;
- case ORAB:
- C_ior(size);
- break;
- }
- break;
- case FLOAT:
- case DOUBLE:
- switch (oper) {
- case PLUSAB:
- case PLUSPLUS:
- case POSTINCR:
- C_adf(size);
- break;
- case MINAB:
- case MINMIN:
- case POSTDECR:
- C_sbf(size);
- break;
- case TIMESAB:
- C_mlf(size);
- break;
- case DIVAB:
- C_dvf(size);
- break;
- }
- break;
- case POINTER:
- if (oper == MINAB || oper == MINMIN || oper == POSTDECR)
- C_ngi(size);
- C_ads(size);
- break;
- case ERRONEOUS:
- break;
- default:
- crash("(assop) bad type %s\n", symbol2str(type->tp_fund));
- }
- }
- /* tmp_pointer_var() returns the EM address of a new temporary
- pointer variable needed at increment, decrement and assignment
- operations to store the address of some variable or lvalue-expression.
- */
- arith
- tmp_pointer_var(oldoffset)
- arith *oldoffset; /* previous allocated address */
- {
- struct stack_level *stl = local_level;
- *oldoffset = stl->sl_local_offset;
- stl->sl_local_offset =
- - align(-stl->sl_local_offset + pointer_size, pointer_align);
- if (stl->sl_local_offset < stl->sl_max_block)
- stl->sl_max_block = stl->sl_local_offset;
- return stl->sl_local_offset;
- }
- /* free_tmp_var() returns the address allocated by tmp_pointer_var()
- and resets the last allocated address.
- */
- free_tmp_var(oldoffset)
- arith oldoffset;
- {
- local_level->sl_local_offset = oldoffset;
- }
- /* store_val() generates code for a store operation.
- There are four ways of storing data:
- - into a global variable
- - into an automatic local variable
- - into a local static variable
- - absolute addressing
- When the destination is described by an (lvalue) expression, the call
- is "store_val(ex->VL_IDF, ex->ex_type, ex->VL_VALUE)"
- */
- store_val(id, tp, offs)
- register struct idf *id;
- struct type *tp;
- arith offs;
- {
- arith size = tp->tp_size;
- int tpalign = tp->tp_align;
- if (id) {
- register struct def *df = id->id_def;
- int al_on_word = (tpalign % word_align == 0);
- register inword = (size == word_size && al_on_word);
- register indword = (size == dword_size && al_on_word);
- if (df->df_level == L_GLOBAL) {
- if (inword)
- C_ste_dnam(id->id_text, offs);
- else
- if (indword)
- C_sde_dnam(id->id_text, offs);
- else {
- C_lae_dnam(id->id_text, offs);
- store_block(size, tpalign);
- }
- }
- else
- if (df->df_sc == STATIC) {
- if (inword)
- C_ste_dlb((label)df->df_address, offs);
- else
- if (indword)
- C_sde_dlb((label)df->df_address, offs);
- else {
- C_lae_dlb((label)df->df_address, offs);
- store_block(size, tpalign);
- }
- }
- else {
- if (inword)
- C_stl(df->df_address + offs);
- else
- if (indword)
- C_sdl(df->df_address + offs);
- else {
- C_lal(df->df_address + offs);
- store_block(size, tpalign);
- df->df_register = REG_NONE;
- }
- }
- }
- else { /* absolute addressing */
- load_cst(offs, pointer_size);
- store_block(size, tpalign);
- }
- }
- /* load_val() generates code for stacking a certain value (from ex),
- which can be obtained in one of the following ways:
- - value from absolute addressed memory
- - constant value
- - function result
- - global variable
- - static variable
- - local variable
- */
- load_val(expr, val)
- struct expr *expr; /* expression containing the value */
- int val; /* generate either LVAL or RVAL */
- {
- register struct idf *id;
- register struct type *tp = expr->ex_type;
- register struct def *df;
- register rvalue = (val == RVAL && expr->ex_lvalue != 0);
- register arith exval = expr->VL_VALUE;
- register arith size = tp->tp_size;
- register tpalign = tp->tp_align;
- register al_on_word = (tpalign % word_align == 0);
- if ((id = expr->VL_IDF) == 0) {
- /* Note: enum constants are also dealt with here */
- if (rvalue) {
- /* absolute addressing
- */
- load_cst(exval, pointer_size);
- load_block(size, tpalign);
- }
- else /* integer, unsigned, long, enum etc */
- load_cst(exval, size);
- }
- else
- if ((df = id->id_def)->df_type->tp_fund == FUNCTION)
- /* the previous statement tried to catch a function
- identifier, which may be cast to a pointer to a
- function.
- ASSERT(!(rvalue)); ???
- */
- C_lpi(id->id_text);
- else
- if (df->df_level == L_GLOBAL) {
- if (rvalue) {
- if (size == word_size && al_on_word)
- C_loe_dnam(id->id_text, exval);
- else
- if (size == dword_size && al_on_word)
- C_lde_dnam(id->id_text, exval);
- else {
- C_lae_dnam(id->id_text, exval);
- load_block(size, tpalign);
- }
- }
- else {
- C_lae_dnam(id->id_text, (arith)0);
- C_adp(exval);
- }
- }
- else
- if (df->df_sc == STATIC) {
- if (rvalue) {
- if (size == word_size && al_on_word)
- C_loe_dlb((label)df->df_address, exval);
- else
- if (size == dword_size && al_on_word)
- C_lde_dlb((label)df->df_address, exval);
- else {
- C_lae_dlb((label)df->df_address, exval);
- load_block(size, tpalign);
- }
- }
- else {
- C_lae_dlb((label)df->df_address, (arith)0);
- C_adp(exval);
- }
- }
- else {
- if (rvalue) {
- if (size == word_size && al_on_word)
- C_lol(df->df_address + exval);
- else
- if (size == dword_size && al_on_word)
- C_ldl(df->df_address + exval);
- else {
- C_lal(df->df_address + exval);
- load_block(size, tpalign);
- df->df_register = REG_NONE;
- }
- }
- else {
- /* following code may be used when
- comparing addresses as in the following
- example:
- f() {
- int a[10], *i;
- for (i = &a[0]; i < &a[10]; i++) ...;
- }
- We don't accept the contents of a[10] to
- be legitimate, so the RVAL of it may
- contain a big mess.
- */
- C_lal(df->df_address);
- C_adp(exval);
- df->df_register = REG_NONE;
- }
- }
- }
- load_cst(val, siz)
- arith val, siz;
- {
- if (siz <= word_size)
- C_loc(val);
- else
- if (siz == dword_size)
- C_ldc(val);
- else {
- label datlab;
- C_df_dlb(datlab = data_label());
- C_rom_icon(long2str((long)val, 10), siz);
- C_lae_dlb(datlab, (arith)0);
- C_loi(siz);
- }
- }
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