X-Git-Url: http://j8takagi.net/cgi-bin/gitweb.cgi?p=YACASL2.git;a=blobdiff_plain;f=src%2Fexec.c;h=8df0765e38c52da163d25e89fae000bd40671cab;hp=a6c7edcd830e280ef8a64938d7978e6c00363245;hb=b4050c46133a58386b6ff3962357a56cf84a19aa;hpb=03e322484530da78d796401413d9f5f493d95345

diff --git a/src/exec.c b/src/exec.c
index a6c7edc..8df0765 100644
--- a/src/exec.c
+++ b/src/exec.c
@@ -1,9 +1,4 @@
-#include <stdio.h>
-#include <assert.h>
-#include <time.h>
-
 #include "exec.h"
-#include "cerr.h"
 
 /**
  * @brief プログラムレジスタ（PR）を表すWORD値を文字列に変換
@@ -91,17 +86,9 @@ static CERR cerr_exec[] = {
 };
 
 /**
- * @brief アセンブル結果読み込みエラーの定義
- */
-static CERR cerr_load[] = {
-    { 210, "load - memory overflow" },
-    { 211, "object file not specified" },
-};
-
-/**
- * @brief 実行モード: trace, logical, dump
+ * @brief 実行モード: trace, logical, dump, dump_start, dump_end,  monitor, step
  */
-EXECMODE execmode = {false, false, false};
+EXECMODE execmode = {false, false, false, 0, 0xFFFF, false, false};
 
 char *pr2str(WORD pr)
 {
@@ -114,14 +101,14 @@ char *pr2str(WORD pr)
 void svcin()
 {
     int i;
-    char *buffer = malloc_chk(INSIZE + 1, "svcin.buffer");
+    char *buf = malloc_chk(INSIZE + 1, "svcin.buf");
 
-    if(fgets(buffer, INSIZE, stdin) == NULL) {
+    if(fgets(buf, INSIZE, stdin) == NULL) {
         sys->memory[sys->cpu->gr[1]] = sys->memory[sys->cpu->gr[2]] = 0x0;
         return;
     }
     for(i = 0; i < INSIZE; i++) {
-        if(*(buffer + i) == '\0' || *(buffer + i) == '\n') {
+        if(!buf[i] || buf[i] == '\n') {
             --i;
             break;
         }
@@ -129,10 +116,10 @@ void svcin()
             setcerr(208, "");    /* SVC input - memory overflow */
             break;
         }
-        sys->memory[sys->cpu->gr[1]+i] = *(buffer + i);
+        sys->memory[sys->cpu->gr[1] + i] = buf[i];
     }
     sys->memory[sys->cpu->gr[2]] = i + 1;
-    FREE(buffer);
+    FREE(buf);
 }
 
 void svcout()
@@ -174,8 +161,8 @@ void setfr(WORD adr)
 
 WORD get_r_r1(WORD oprx)
 {
-    WORD r;
-    char *s;
+    WORD r = 0;
+    char *s = NULL;
 
     if((r = ((oprx & 0x00F0) >>4)) > GRSIZE - 1) {
         setcerr(205, s = pr2str(sys->cpu->pr));    /* r/r1 in word #1 - not GR */
@@ -187,8 +174,8 @@ WORD get_r_r1(WORD oprx)
 
 WORD get_x_r2(WORD oprx)
 {
-    WORD x;
-    char *s;
+    WORD x = 0;
+    char *s = NULL;
 
     if((x = (oprx & 0x000F)) > GRSIZE - 1) {
         setcerr(206, s = pr2str(sys->cpu->pr));    /* r/r1 in word #1 - not GR */
@@ -200,8 +187,10 @@ WORD get_x_r2(WORD oprx)
 
 WORD get_adr_x(WORD adr, WORD oprx)
 {
-    WORD a = adr, x;
-    if((x = get_x_r2(oprx)) > 0) {
+    WORD a = adr;
+    WORD x = get_x_r2(oprx);
+
+    if(x > 0) {
         a += sys->cpu->gr[x];
     }
     return a;
@@ -209,8 +198,8 @@ WORD get_adr_x(WORD adr, WORD oprx)
 
 WORD get_val_adr_x(WORD adr, WORD oprx)
 {
-    WORD a;
-    char *s;
+    WORD a = 0;
+    char *s = NULL;
 
     if((a = get_adr_x(adr, oprx)) >= sys->memsize) {
         setcerr(207, s = pr2str(sys->cpu->pr + 1));    /* address in word #2 - out of memory */
@@ -221,37 +210,11 @@ WORD get_val_adr_x(WORD adr, WORD oprx)
 }
 
 /* exec.hで定義された関数群 */
-void addcerrlist_load()
-{
-    addcerrlist(ARRAYSIZE(cerr_load), cerr_load);
-}
-
 void addcerrlist_exec()
 {
     addcerrlist(ARRAYSIZE(cerr_exec), cerr_exec);
 }
 
-bool loadassemble(const char *file)
-{
-    FILE *fp;
-    bool stat = true;
-
-    assert(file != NULL);
-    if((fp = fopen(file, "r")) == NULL) {
-        perror(file);
-        return false;
-    }
-    execptr->end = execptr->start +
-        fread(sys->memory, sizeof(WORD), sys->memsize - execptr->start, fp);
-    if(execptr->end == sys->memsize) {
-        setcerr(210, file);    /* load - memory overflow */
-        fprintf(stderr, "Load error - %d: %s\n", cerr->num, cerr->msg);
-        stat = false;
-    }
-    fclose(fp);
-    return stat;
-}
-
 void nop()
 {
     sys->cpu->pr += 1;
@@ -259,35 +222,28 @@ void nop()
 
 void ld_r_adr_x()
 {
-    WORD w[2];
-    w[0] = sys->memory[sys->cpu->pr];
-    w[1] = sys->memory[sys->cpu->pr + 1];
+    WORD w[] = {sys->memory[sys->cpu->pr], sys->memory[sys->cpu->pr + 1]};
     setfr(sys->cpu->gr[get_r_r1(w[0])] = get_val_adr_x(w[1], w[0]));
     sys->cpu->pr += 2;
 }
 
 void ld_r1_r2()
 {
-    WORD w[1];
-    w[0] = sys->memory[sys->cpu->pr];
+    WORD w[] = {sys->memory[sys->cpu->pr]};
     setfr(sys->cpu->gr[get_r_r1(w[0])] = sys->cpu->gr[get_x_r2(w[0])]);
     sys->cpu->pr += 1;
 }
 
 void st()
 {
-    WORD w[2];
-    w[0] = sys->memory[sys->cpu->pr];
-    w[1] = sys->memory[sys->cpu->pr + 1];
+    WORD w[] = {sys->memory[sys->cpu->pr], sys->memory[sys->cpu->pr + 1]};
     sys->memory[get_adr_x(w[1], w[0])] = sys->cpu->gr[get_r_r1(w[0])];
     sys->cpu->pr += 2;
 }
 
 void lad()
 {
-    WORD w[2];
-    w[0] = sys->memory[sys->cpu->pr];
-    w[1] = sys->memory[sys->cpu->pr + 1];
+    WORD w[] = {sys->memory[sys->cpu->pr], sys->memory[sys->cpu->pr + 1]};
     sys->cpu->gr[get_r_r1(w[0])] = get_adr_x(w[1], w[0]);
     sys->cpu->pr += 2;
 }
@@ -313,141 +269,137 @@ void adda(WORD r, WORD val)
 
 void adda_r_adr_x()
 {
-    WORD w[2];
-    w[0] = sys->memory[sys->cpu->pr];
-    w[1] = sys->memory[sys->cpu->pr + 1];
+    WORD w[] = {sys->memory[sys->cpu->pr], sys->memory[sys->cpu->pr + 1]};
     adda(get_r_r1(w[0]), get_val_adr_x(w[1], w[0]));
     sys->cpu->pr += 2;
 }
 
 void adda_r1_r2()
 {
-    WORD w[1];
-    w[0] = sys->memory[sys->cpu->pr];
+    WORD w[] = {sys->memory[sys->cpu->pr]};
     adda(get_r_r1(w[0]), sys->cpu->gr[get_x_r2(w[0])]);
     sys->cpu->pr += 1;
 }
 
 void suba_r_adr_x()
 {
-    WORD w[2];
-    w[0] = sys->memory[sys->cpu->pr];
-    w[1] = sys->memory[sys->cpu->pr + 1];
+    WORD w[] = {sys->memory[sys->cpu->pr], sys->memory[sys->cpu->pr + 1]};
     adda(get_r_r1(w[0]), ~(get_val_adr_x(w[1], w[0])) + 1);
     sys->cpu->pr += 2;
 }
 
 void suba_r1_r2()
 {
-    WORD w[1];
-    w[0] = sys->memory[sys->cpu->pr];
+    WORD w[] = {sys->memory[sys->cpu->pr]};
     adda(get_r_r1(w[0]), ~(sys->cpu->gr[get_x_r2(w[0])]) + 1);
     sys->cpu->pr += 1;
 }
 
-void addl(WORD r, WORD val)
+void addl_gr(WORD r, WORD val, bool add)
 {
-    long tmp;
-    sys->cpu->fr = 0x0;
+    unsigned long o = 0;
+    unsigned long s = 0;
 
-    if((tmp = sys->cpu->gr[r] + val) < 0 || tmp > 65535) {
-        sys->cpu->fr += OF;
+    o = sys->cpu->gr[r];
+    sys->cpu->fr = 0;    /* flag initialize */
+
+    if(add == true) {
+        s = o + val;
+        if(s > 0xFFFF) {
+            sys->cpu->fr += OF;
+        }
+    } else {
+        if(o < val) {
+            sys->cpu->fr += OF;
+        }
+        s = o + (~val + 1);
+        if(s > 0xFFFF) {
+            s &= 0xFFFF;
+        }
     }
-    if(((sys->cpu->gr[r] = (WORD)(tmp & 0xFFFF)) & 0x8000) == 0x8000) {
+    sys->cpu->gr[r] = (WORD)s;
+
+    if((s & 0x8000) == 0x8000) {
         sys->cpu->fr += SF;
-    } else if(sys->cpu->gr[r] == 0x0) {
+    }
+    else if(s == 0x0) {
         sys->cpu->fr += ZF;
     }
 }
 
 void addl_r_adr_x()
 {
-    WORD w[2];
-    w[0] = sys->memory[sys->cpu->pr];
-    w[1] = sys->memory[sys->cpu->pr + 1];
-    addl(get_r_r1(w[0]), get_val_adr_x(w[1], w[0]));
+    WORD w[] = {sys->memory[sys->cpu->pr], sys->memory[sys->cpu->pr + 1]};
+    addl_gr(get_r_r1(w[0]), get_val_adr_x(w[1], w[0]), true);
     sys->cpu->pr += 2;
 }
 
 void addl_r1_r2()
 {
-    WORD w[1];
-    w[0] = sys->memory[sys->cpu->pr];
-    addl(get_r_r1(w[0]), sys->cpu->gr[get_x_r2(w[0])]);
+    WORD w[] = {sys->memory[sys->cpu->pr]};
+    addl_gr(get_r_r1(w[0]), sys->cpu->gr[get_x_r2(w[0])], true);
     sys->cpu->pr += 1;
 }
 
 void subl_r_adr_x()
 {
-    WORD w[2];
-    w[0] = sys->memory[sys->cpu->pr];
-    w[1] = sys->memory[sys->cpu->pr + 1];
-    addl(get_r_r1(w[0]), ~(get_val_adr_x(w[1], w[0])) + 1);
+    WORD w[] = {sys->memory[sys->cpu->pr], sys->memory[sys->cpu->pr + 1]};
+    addl_gr(get_r_r1(w[0]), get_val_adr_x(w[1], w[0]), false);
     sys->cpu->pr += 2;
 }
 
 void subl_r1_r2()
 {
-    WORD w[1];
-    w[0] = sys->memory[sys->cpu->pr];
-    addl(get_r_r1(w[0]), ~(sys->cpu->gr[get_x_r2(w[0])]) + 1);
+    WORD w[] = {sys->memory[sys->cpu->pr]};
+    addl_gr(get_r_r1(w[0]), sys->cpu->gr[get_x_r2(w[0])], false);
     sys->cpu->pr += 1;
 }
 
 void and_r_adr_x()
 {
-    WORD w[2];
-    w[0] = sys->memory[sys->cpu->pr];
-    w[1] = sys->memory[sys->cpu->pr + 1];
+    WORD w[] = {sys->memory[sys->cpu->pr], sys->memory[sys->cpu->pr + 1]};
     setfr(sys->cpu->gr[get_r_r1(w[0])] &= get_val_adr_x(w[1], w[0]));
     sys->cpu->pr += 2;
 }
 
 void and_r1_r2()
 {
-    WORD w[1];
-    w[0] = sys->memory[sys->cpu->pr];
+    WORD w[] = {sys->memory[sys->cpu->pr]};
     setfr(sys->cpu->gr[get_r_r1(w[0])] &= sys->cpu->gr[get_x_r2(w[0])]);
     sys->cpu->pr += 1;
 }
 
 void or_r_adr_x()
 {
-    WORD w[2];
-    w[0] = sys->memory[sys->cpu->pr];
-    w[1] = sys->memory[sys->cpu->pr + 1];
+    WORD w[] = {sys->memory[sys->cpu->pr], sys->memory[sys->cpu->pr + 1]};
     setfr(sys->cpu->gr[get_r_r1(w[0])] |= get_val_adr_x(w[1], w[0]));
     sys->cpu->pr += 2;
 }
 
 void or_r1_r2()
 {
-    WORD w[1];
-    w[0] = sys->memory[sys->cpu->pr];
+    WORD w[] = {sys->memory[sys->cpu->pr]};
     setfr(sys->cpu->gr[get_r_r1(w[0])] |= sys->cpu->gr[get_x_r2(w[0])]);
     sys->cpu->pr += 1;
 }
 
 void xor_r_adr_x()
 {
-    WORD w[2];
-    w[0] = sys->memory[sys->cpu->pr];
-    w[1] = sys->memory[sys->cpu->pr + 1];
+    WORD w[] = {sys->memory[sys->cpu->pr], sys->memory[sys->cpu->pr + 1]};
     setfr(sys->cpu->gr[get_r_r1(w[0])] ^= get_val_adr_x(w[1], w[0]));
     sys->cpu->pr += 2;
 }
 
 void xor_r1_r2()
 {
-    WORD w[1];
-    w[0] = sys->memory[sys->cpu->pr];
+    WORD w[] = {sys->memory[sys->cpu->pr]};
     setfr(sys->cpu->gr[get_r_r1(w[0])] ^= sys->cpu->gr[get_x_r2(w[0])]);
     sys->cpu->pr += 1;
 }
 
 void cpa(WORD r, WORD val)
 {
-    sys->cpu->fr = 0x0;
+    sys->cpu->fr = 0;
     if((short)sys->cpu->gr[r] < (short)val) {
         sys->cpu->fr = SF;
     } else if(sys->cpu->gr[r] == val) {
@@ -457,17 +409,14 @@ void cpa(WORD r, WORD val)
 
 void cpa_r_adr_x()
 {
-    WORD w[2];
-    w[0] = sys->memory[sys->cpu->pr];
-    w[1] = sys->memory[sys->cpu->pr + 1];
+    WORD w[] = {sys->memory[sys->cpu->pr], sys->memory[sys->cpu->pr + 1]};
     cpa(get_r_r1(w[0]), get_val_adr_x(w[1], w[0]));
     sys->cpu->pr += 2;
 }
 
 void cpa_r1_r2()
 {
-    WORD w[1];
-    w[0] = sys->memory[sys->cpu->pr];
+    WORD w[] = {sys->memory[sys->cpu->pr]};
     cpa(get_r_r1(w[0]), sys->cpu->gr[get_x_r2(w[0])]);
     sys->cpu->pr += 1;
 }
@@ -484,32 +433,28 @@ void cpl(WORD r, WORD val)
 
 void cpl_r_adr_x()
 {
-    WORD w[2];
-    w[0] = sys->memory[sys->cpu->pr];
-    w[1] = sys->memory[sys->cpu->pr + 1];
+    WORD w[] = {sys->memory[sys->cpu->pr], sys->memory[sys->cpu->pr + 1]};
     cpl(get_r_r1(w[0]), get_val_adr_x(w[1], w[0]));
     sys->cpu->pr += 2;
 }
 
 void cpl_r1_r2()
 {
-    WORD w[1];
-    w[0] = sys->memory[sys->cpu->pr];
+    WORD w[] = {sys->memory[sys->cpu->pr]};
     cpl(get_r_r1(w[0]), sys->cpu->gr[get_x_r2(w[0])]);
     sys->cpu->pr += 1;
 }
 
 void sla()
 {
-    WORD w[2], sign, last = 0x0, r;
-    int i;
+    WORD w[] = {sys->memory[sys->cpu->pr], sys->memory[sys->cpu->pr + 1]};
+    WORD r = get_r_r1(w[0]);
+    WORD sign = sys->cpu->gr[r] & 0x8000;
+    WORD last = 0;
 
-    w[0] = sys->memory[sys->cpu->pr];
-    w[1] = sys->memory[sys->cpu->pr + 1];
-    sys->cpu->fr = 0x0;
-    sign = sys->cpu->gr[(r = get_r_r1(w[0]))] & 0x8000;
+    sys->cpu->fr = 0;
     sys->cpu->gr[r] &= 0x7FFF;
-    for(i = 0; i < get_adr_x(w[1], w[0]); i++) {
+    for(int i = 0; i < get_adr_x(w[1], w[0]); i++) {
         last = sys->cpu->gr[r] & 0x4000;
         sys->cpu->gr[r] <<= 1;
     }
@@ -531,15 +476,14 @@ void sla()
 
 void sra()
 {
-    WORD w[2], sign, last = 0x0, r;
-    int i;
+    WORD w[] = {sys->memory[sys->cpu->pr], sys->memory[sys->cpu->pr + 1]};
+    WORD r = get_r_r1(w[0]);
+    WORD sign = sys->cpu->gr[r] & 0x8000;
+    WORD last = 0;
 
-    w[0] = sys->memory[sys->cpu->pr];
-    w[1] = sys->memory[sys->cpu->pr + 1];
-    sys->cpu->fr = 0x0;
-    sign = sys->cpu->gr[(r = get_r_r1(w[0]))] & 0x8000;
+    sys->cpu->fr = 0;
     sys->cpu->gr[r] &= 0x7FFF;
-    for(i = 0; i < get_adr_x(w[1], w[0]); i++) {
+    for(int i = 0; i < get_adr_x(w[1], w[0]); i++) {
         last = sys->cpu->gr[r] & 0x1;
         sys->cpu->gr[r] >>= 1;
         if(sign > 0) {
@@ -564,14 +508,13 @@ void sra()
 
 void sll()
 {
-    WORD w[2], last = 0x0, r;
-    int i;
+    WORD w[] = {sys->memory[sys->cpu->pr], sys->memory[sys->cpu->pr + 1]};
+    WORD last = 0;
+    WORD r = get_r_r1(w[0]);
 
-    w[0] = sys->memory[sys->cpu->pr];
-    w[1] = sys->memory[sys->cpu->pr + 1];
     sys->cpu->fr = 0x0;
-    for(i = 0; i < get_adr_x(w[1], w[0]); i++) {
-        last = sys->cpu->gr[(r = get_r_r1(w[0]))] & 0x8000;
+    for(int i = 0; i < get_adr_x(w[1], w[0]); i++) {
+        last = sys->cpu->gr[r] & 0x8000;
         sys->cpu->gr[r] <<= 1;
     }
     /* OFに、レジスタから最後に送り出されたビットの値を設定 */
@@ -591,14 +534,12 @@ void sll()
 
 void srl()
 {
-    WORD w[2], last = 0x0, r;
-    int i;
+    WORD w[] = {sys->memory[sys->cpu->pr], sys->memory[sys->cpu->pr + 1]};
+    WORD last = 0;
+    WORD r = get_r_r1(w[0]);
 
-    w[0] = sys->memory[sys->cpu->pr];
-    w[1] = sys->memory[sys->cpu->pr + 1];
     sys->cpu->fr = 0x0;
-    r = get_r_r1(w[0]);
-    for(i = 0; i < get_adr_x(w[1], w[0]); i++) {
+    for(int i = 0; i < get_adr_x(w[1], w[0]); i++) {
         last = sys->cpu->gr[r] & 0x0001;
         sys->cpu->gr[r] >>= 1;
     }
@@ -619,9 +560,7 @@ void srl()
 
 void jpl()
 {
-    WORD w[2];
-    w[0] = sys->memory[sys->cpu->pr];
-    w[1] = sys->memory[sys->cpu->pr + 1];
+    WORD w[] = {sys->memory[sys->cpu->pr], sys->memory[sys->cpu->pr + 1]};
     if((sys->cpu->fr & (SF | ZF)) == 0) {
         sys->cpu->pr = get_adr_x(w[1], w[0]);
     } else {
@@ -631,9 +570,7 @@ void jpl()
 
 void jmi()
 {
-    WORD w[2];
-    w[0] = sys->memory[sys->cpu->pr];
-    w[1] = sys->memory[sys->cpu->pr + 1];
+    WORD w[] = {sys->memory[sys->cpu->pr], sys->memory[sys->cpu->pr + 1]};
     if((sys->cpu->fr & SF) > 0) {
         sys->cpu->pr = get_adr_x(w[1], w[0]);
     } else {
@@ -643,9 +580,7 @@ void jmi()
 
 void jnz()
 {
-    WORD w[2];
-    w[0] = sys->memory[sys->cpu->pr];
-    w[1] = sys->memory[sys->cpu->pr + 1];
+    WORD w[] = {sys->memory[sys->cpu->pr], sys->memory[sys->cpu->pr + 1]};
     if((sys->cpu->fr & ZF) == 0) {
         sys->cpu->pr = get_adr_x(w[1], w[0]);
     } else {
@@ -655,9 +590,7 @@ void jnz()
 
 void jze()
 {
-    WORD w[2];
-    w[0] = sys->memory[sys->cpu->pr];
-    w[1] = sys->memory[sys->cpu->pr + 1];
+    WORD w[] = {sys->memory[sys->cpu->pr], sys->memory[sys->cpu->pr + 1]};
     if((sys->cpu->fr & ZF) > 0) {
         sys->cpu->pr = get_adr_x(w[1], w[0]);
     } else {
@@ -667,9 +600,7 @@ void jze()
 
 void jov()
 {
-    WORD w[2];
-    w[0] = sys->memory[sys->cpu->pr];
-    w[1] = sys->memory[sys->cpu->pr + 1];
+    WORD w[] = {sys->memory[sys->cpu->pr], sys->memory[sys->cpu->pr + 1]};
     if((sys->cpu->fr & OF) > 0) {
         sys->cpu->pr = get_adr_x(w[1], w[0]);
     } else {
@@ -679,19 +610,14 @@ void jov()
 
 void jump()
 {
-    WORD w[2];
-    w[0] = sys->memory[sys->cpu->pr];
-    w[1] = sys->memory[sys->cpu->pr + 1];
+    WORD w[] = {sys->memory[sys->cpu->pr], sys->memory[sys->cpu->pr + 1]};
     sys->cpu->pr = get_adr_x(w[1], w[0]);
 }
 
 void push()
 {
     assert(sys->cpu->sp > execptr->end && sys->cpu->sp <= sys->memsize);
-    WORD w[2];
-
-    w[0] = sys->memory[sys->cpu->pr];
-    w[1] = sys->memory[sys->cpu->pr + 1];
+    WORD w[] = {sys->memory[sys->cpu->pr], sys->memory[sys->cpu->pr + 1]};
     sys->memory[--(sys->cpu->sp)] = get_adr_x(w[1], w[0]);
     sys->cpu->pr += 2;
 }
@@ -699,15 +625,14 @@ void push()
 void pop()
 {
     assert(sys->cpu->sp > execptr->end);
-    WORD w;
-    char *s;
+    WORD w[] = {sys->memory[sys->cpu->pr]};
+    char *s = NULL;
 
     if(sys->cpu->sp >= sys->memsize) {
         setcerr(203, s = pr2str(sys->cpu->pr));        /* Stack Pointer (SP) - stack underflow */
         FREE(s);
     } else {
-        w = sys->memory[sys->cpu->pr];
-        sys->cpu->gr[get_r_r1(w)] = sys->memory[(sys->cpu->sp)++];
+        sys->cpu->gr[get_r_r1(w[0])] = sys->memory[(sys->cpu->sp)++];
         sys->cpu->pr += 1;
     }
 }
@@ -715,9 +640,7 @@ void pop()
 void call()
 {
     assert(sys->cpu->sp > execptr->end && sys->cpu->sp <= sys->memsize);
-    WORD w[2];
-    w[0] = sys->memory[sys->cpu->pr];
-    w[1] = sys->memory[sys->cpu->pr + 1];
+    WORD w[] = {sys->memory[sys->cpu->pr], sys->memory[sys->cpu->pr + 1]};
     sys->memory[--(sys->cpu->sp)] = sys->cpu->pr + 1;
     sys->cpu->pr = get_adr_x(w[1], w[0]);
 }
@@ -734,9 +657,7 @@ void ret()
 
 void svc()
 {
-    WORD w[2];
-    w[0] = sys->memory[sys->cpu->pr];
-    w[1] = sys->memory[sys->cpu->pr + 1];
+    WORD w[] = {sys->memory[sys->cpu->pr], sys->memory[sys->cpu->pr + 1]};
     switch(get_adr_x(w[1], w[0]))
     {
     case 0x0:                   /* STOP */
@@ -754,11 +675,14 @@ void svc()
 
 void exec()
 {
-    clock_t clock_begin, clock_end;
-    void (*cmdptr)();
-    char *s;
+    clock_t clock_begin = 0;
+    clock_t clock_end = 0;
+    void (*cmdptr)() = NULL;
+    char *s = NULL;
+    const char *monmsg = "COMET II machine code monitor. Type ? for help.\n";
+
+    create_cmdtable(HASH_CODE);                 /* 命令のコードとタイプがキーのハッシュ表を作成 */
 
-    create_code_cmdtype();                          /* 命令のコードとタイプがキーのハッシュ表を作成 */
     if(execmode.trace == true) {
         fprintf(stdout, "\nExecuting machine codes\n");
     }
@@ -772,27 +696,34 @@ void exec()
             }
             if(execmode.dump) {                    /* dumpオプション指定時、メモリを出力 */
                 fprintf(stdout, "#%04X: Memory::::\n", sys->cpu->pr);
-                dumpmemory();
+                dumpmemory(execmode.dump_start, execmode.dump_end);
             }
             fprintf(stdout, "\n");
         }
+        /* ステップモードまたはブレークポイントの場合、モニターを起動 */
+        if(
+            (execmode.monitor == true && sys->cpu->pr == execptr->start) ||
+            execmode.step == true || getbps(sys->cpu->pr) == true)
+        {
+            if(sys->cpu->pr == execptr->start) {
+                fprintf(stdout, "%s", monmsg);
+            }
+            monitor();
+        }
         /* プログラムレジスタをチェック */
         if(sys->cpu->pr >= sys->memsize) {
             setcerr(201, s = pr2str(sys->cpu->pr));        /* Program Register (PR) - memory overflow */
-            FREE(s);
             goto execfin;
         }
         /* スタックポインタをチェック */
         if(sys->cpu->sp <= execptr->end) {
             setcerr(202, s = pr2str(sys->cpu->pr));        /* Stack Pointer (SP) - stack overflow */
-            FREE(s);
             goto execfin;
         }
         /* コードから命令を取得 */
         /* 取得できない場合はエラー終了 */
         if((cmdptr = getcmdptr(sys->memory[sys->cpu->pr] & 0xFF00)) == NULL) {
             setcerr(204, s = pr2str(sys->cpu->pr));            /* OP in word #1 - not command code */
-            FREE(s);
             goto execfin;
         }
         /* 命令の実行 */
@@ -801,9 +732,14 @@ void exec()
         if(cerr->num > 0) {
             goto execfin;
         }
-        /* 終了フラグがtrueの場合は、正常終了 */
+        /* 終了フラグがtrueの場合は、モニターまたは正常終了 */
         if(execptr->stop == true) {
-            break;
+            if(execmode.monitor == true) {
+                fprintf(stdout, "Return to top.\n");
+                monitor();
+            } else {
+                break;
+            }
         }
         /* クロック周波数の設定 */
         do {
@@ -811,7 +747,9 @@ void exec()
         } while(clock_end - clock_begin < CLOCKS_PER_SEC / sys->clocks);
     }
 execfin:
-    free_code_cmdtype();                           /* 命令のコードとタイプがキーのハッシュ表を解放 */
+    FREE(s);
+    freebps();
+    free_cmdtable(HASH_CODE);              /* 命令のコードとタイプがキーのハッシュ表を解放 */
     if(cerr->num > 0) {
         fprintf(stderr, "Execute error - %d: %s\n", cerr->num, cerr->msg);
     }