Trial command line option to suppress updating PRIMOS' DATNOW variable.

The link in README.md to install instructions was either old or
never quite right.  Point to DRB's overview document now, which
points (near) to the version specific ones.

README.md

@@ -55,7 +55,7 @@ business unit ceased to exist.  A reformatted copy is available
 A growing collection of Prime and related documentation is available
 at [sysovl.info](https://sysovl.info/reference_prime.html).
 A howto on installing PRIMOS in the emulator is
-[here](https://sysovl.info/reference_prime_drb_installing_primos.html).
+[here](https://sysovl.info/reference_prime_drb_installoview.html).
 Discussion of adapting these instructions to
 22.1.4 has been occurring on the [cctalk mailing
 list](http://classiccmp.org/pipermail/cctalk/2020-March/052126.html).

devamlc.h

@@ -1,4 +1,4 @@
-/* 
+/*
   Implements the AMLC subsystem for Primos.  In earlier versions
   (r186), a more hardware-centric implementation was used that closely
   followed the design of Prime's real AMLC board.  For example, every
@@ -52,9 +52,9 @@
   NOTE: varying the AMLC poll rates dynamically is the default, but
         this can lead to unpredictable performance.  If consistent,
         predictable performance is more important than absolute
-        performance, MAXAMLCSPEEDUP can be set to 1.  Then this 
+        performance, MAXAMLCSPEEDUP can be set to 1.  Then this
         implementation will function more or less like a real Prime.
-    
+
 
   AMLC I/O operations:
 
@@ -133,7 +133,7 @@
 AMLC status word (from AMLCT5):
 
      BITS                 DESCRIPTION
-  
+
       1                   END OF RANGE INTERRUPT
       2                   CLOCK RUNNING
       3-6                 LINE # OF LINE WHOSE DATA SET STATUS HAS CHANGED
@@ -150,6 +150,8 @@ AMLC status word (from AMLCT5):
 
 */
 
+#include <termio.h>
+
 /* this macro closes an AMLC connection - used in several places
 
    NOTE: don't print disconnect message on dedicated lines */
@@ -202,11 +204,11 @@ int devamlc (int class, int func, int device) {
 #define DSSCOUNTDOWN 25
 
   /* connection types for each line.  This _doesn't_ imply the line is
-     actually connected, ie, an AMLC line may be tied to a specific 
+     actually connected, ie, an AMLC line may be tied to a specific
      serial device (like a USB->serial gizmo), but the USB device may
      not be plugged in.  The connection type would be CT_SERIAL but
      the line's fd would be -1 and the "connected" bit would be 0 */
-     
+
 #define CT_SOCKET 1
 #define CT_SERIAL 2
 #define CT_DEDIP 3
@@ -324,7 +326,7 @@ int devamlc (int class, int func, int device) {
       int tempport;
       struct hostent* host;
       char *p;
-  
+
       /* initially, we don't know about any AMLC boards */
 
       for (dx=0; dx<MAXBOARDS; dx++) {
@@ -346,7 +348,7 @@ int devamlc (int class, int func, int device) {
       /* read the amlc.cfg file.  This file has 3 uses:
 
          1. maps Prime async lines to real serial devices, like host
-            serial ports or USB serial boxes.  
+            serial ports or USB serial boxes.
 
             Format: <line #> /dev/<Unix usb device name>
 
@@ -418,7 +420,7 @@ int devamlc (int class, int func, int device) {
               fprintf(stderr,"Line %d of amlc.cfg ignored: IP address too long\n", lc);
               continue;
             }
-            
+
             /* break out host and port number; no port means this is
                an incoming dedicated line: no connects out.  With a
                port means we need to connect to it. */
@@ -553,13 +555,13 @@ int devamlc (int class, int func, int device) {
     /* XXX: this constant is redefined because of a bug in the
        OSX Prolific USB serial driver at version 1.2.1r2.  They should be
        turning on bit 0100, but are turning on 0x0100. */
-#define TIOCM_CD 0x0100    
+#define TIOCM_CD 0x0100
 
     if (func == 00) {             /* input Data Set Sense (carrier) */
       if (dc[dx].serial) {        /* any serial connections? */
         if (--dc[dx].dsstime == 0) {
           dc[dx].dsstime = DSSCOUNTDOWN;
-#ifdef __APPLE__
+/* #ifdef __APPLE__ */
           for (lx = 0; lx < 16; lx++) {  /* yes, poll them */
             if (dc[dx].ctype[lx] == CT_SERIAL) {
               int modemstate;
@@ -575,7 +577,7 @@ int devamlc (int class, int func, int device) {
               }
             }
           }
-#endif
+/* #endif */
         }
       }
       //printf("devamlc: dss for device '%o = 0x%x\n", device, dc[dx].dss);
@@ -634,10 +636,10 @@ int devamlc (int class, int func, int device) {
         }
         break;
 
-        
+
       case CT_SERIAL: {
         int fd;
-            
+
         /* setup line characteristics if they have changed (check for
            something other than DTR changing) */
 
@@ -707,7 +709,7 @@ int devamlc (int class, int func, int device) {
              1_0 - cts/rts flow control (2413 becomes 6413)
              1_1 - dsr/dtr flow control (2413 becomes 7413)
 
-             NOTE: bit 11 also appears to be free, but Primos doesn't 
+             NOTE: bit 11 also appears to be free, but Primos doesn't
              let it flow through to the AMLC controller. :(
           */
 
@@ -758,7 +760,6 @@ int devamlc (int class, int func, int device) {
 
         /* set DTR high (02000) or low if it has changed */
 
-#ifdef __APPLE__
         if ((getcrs16(A) ^ dc[dx].lconf[lx]) & 02000) {
           int modemstate;
           //printf("devamlc: DTR state changed\n");
@@ -771,7 +772,6 @@ int devamlc (int class, int func, int device) {
           }
           ioctl(fd, TIOCMSET, &modemstate);
         }
-#endif
         break;
       }
 
@@ -841,7 +841,7 @@ int devamlc (int class, int func, int device) {
     double ts;
     int neweor, activelines;
     //printf("poll device '%o, speedup=%5.2f, cti=%x, xmit=%x, recv=%x, dss=%x\n", device, pollspeedup, dc[dx].ctinterrupt, dc[dx].xmitenabled, dc[dx].recvenabled, dc[dx].dss);
-    
+
     /* check for 1 new telnet connection every AMLCACCEPTSECS seconds
        (10 times per second) */
 
@@ -1036,7 +1036,7 @@ int devamlc (int class, int func, int device) {
 
                 int fd, sockflags;
                 struct sockaddr_in raddr;
-  
+
                 dc[dx].obtimer[lx] = tv.tv_sec + AMLCCONNECT;
                 //printf("em: trying to connect to 0x%08x:%d\n", dc[dx].obhost[lx], dc[dx].obport[lx]); /***/
                 fd = socket(AF_INET, SOCK_STREAM, 0);
@@ -1121,7 +1121,7 @@ int devamlc (int class, int func, int device) {
     }
 
     /* process input, but only as much as will fit into the DMC
-       buffer.  
+       buffer.
 
        Because the size of the AMLC tumble tables is limited, this
        could pose a denial of service issue.  Input is processed in a

em.c

@@ -274,6 +274,7 @@ static void macheck (unsigned short p300vec, unsigned short chkvec, unsigned int
    T_EAV        trace V-mode effective address calculation
    T_EAI        trace I-mode effective address calculation
    T_FLOW       instruction summary
+   T_FP         floating point
    T_INST       detailed instruction trace
    T_MODE       trace CPU mode changes
    T_EAAP       AP effective address calculation
@@ -311,6 +312,7 @@ static void macheck (unsigned short p300vec, unsigned short chkvec, unsigned int
 #define T_EAS   0x00040000
 #define T_TLB   0x00080000
 #define T_SMLC  0x00100000
+#define T_FP    0x00200000
 
 #define BITMASK16(b) (0x8000 >> ((b)-1))
 #define BITMASK32(b) ((unsigned int)(0x80000000) >> ((b)-1))
@@ -657,6 +659,7 @@ static unsigned short *physmem = NULL; /* system's physical memory */
 #define LASTFAULT     077
 
 //static ea_t tnoua_ea=0, tnou_ea=0, tsrc_ea=0;
+static int noclock;                         /* -noclock arg */
 static int domemdump;                       /* -memdump arg */
 static int dolinecleararg;                  /* -dolineclear arg */
 
@@ -4454,6 +4457,7 @@ int main (int argc, char **argv) {
 
 #include "dispatch.h"
 
+  noclock = 0;
   domemdump = 0;
   dolinecleararg = 0;
   bootarg = NULL;
@@ -4472,6 +4476,9 @@ int main (int argc, char **argv) {
       while (i+1 < argc && argv[i+1][0] != '-')
         readloadmap(argv[++i], 1);
 
+    } else if (strcmp(argv[i],"-noclock") == 0) {
+      noclock = 1;
+
     } else if (strcmp(argv[i],"-memdump") == 0) {
       domemdump = 1;
 
@@ -4618,6 +4625,8 @@ int main (int argc, char **argv) {
           gv.traceflags |= T_TLB;
         else if (strcmp(argv[i],"smlc") == 0)
           gv.traceflags |= T_SMLC;
+        else if (strcmp(argv[i],"fp") == 0)
+          gv.traceflags |= T_FP;
         else if (isdigit(argv[i][0]) && strlen(argv[i]) <= 3 && sscanf(argv[i],"%d", &templ) == 1)
           gv.traceuser = 0100000 | (templ<<6);   /* form OWNERL for user # */
         else if (strlen(argv[i]) == 6 && sscanf(argv[i],"%o", &templ) == 1)

emdev.h

@@ -51,7 +51,7 @@
    '50 = #1 HSSMLC/MDLC (synchronous comm)
    '51 = #2 HSSMLC/MDLC
 *  '52 = #3 AMLC or ICS1
-*  '53 = #2 AMLC 
+*  '53 = #2 AMLC
 *  '54 = #1 AMLC
    '55 = MACI autocall unit
    '56 = old SMLC (RTOS User Guide, A-1 & Hacker's Guide)
@@ -229,7 +229,7 @@ int devnone (int class, int func, int device) {
    OCP '0604 = enable transmit DMA/C
    OCP '0704 = reset transmit interrupt mask and DMA/C enable
    OCP '1004 = Full duplex; software must echo
-   OCP '1104 = output a sync pulse (diagnostics) 
+   OCP '1104 = output a sync pulse (diagnostics)
    OCP '1204 = Prime normal, independent xmit and recv w/echoplex
    OCP '1304 = Self test mode (internally connects transmitter to receiver)
    OCP '1504 = Set both xmit & rcv interrupt masks
@@ -302,7 +302,7 @@ int devasr (int class, int func, int device) {
   int doblock;
   time_t unixtime;
   struct tm *tms;
-  
+
   doblock = BLOCKIO;
 
   switch (class) {
@@ -330,7 +330,7 @@ int devasr (int class, int func, int device) {
       perror(" unable to get tty attributes");
       fatal(NULL);
     }
-    
+
     /* save initial terminal setup to restore when exiting */
 
     origterminfo = terminfo;
@@ -497,7 +497,7 @@ readasr:
           goto readasr;
         }
 #endif
-        
+
         /* if doing local echo, do xon/xoff processing here.  If Unix
            does it, the emulator might block on a console write.  If
            the console is running full-duplex (no local echo), we can
@@ -650,7 +650,7 @@ readasr:
 
 /* Device '14 - magtape controller #1
 
-   NOTES: 
+   NOTES:
 
    This code only supports 1 tape controller (4 units), but could be
    extended to support 2 controllers (eg, see disk controller code)
@@ -863,7 +863,7 @@ fmterr:
       *mtstat |= 0x100;        /* set filemark status */
       goto repo;
     }
-    
+
     /* ignore attempts to backspace over error records.  This will
        cause Magsav to read the next record instead, and it may
        recover.  Re-reading the error record 10 times won't help! */
@@ -881,7 +881,7 @@ fmterr:
     }
 
     /* read leading reclen again to make sure we're positioned correctly */
-      
+
     n = read(fd, buf, 4);
     if (n == -1) goto readerr;
     if (n != 4) {
@@ -974,7 +974,7 @@ int devmt (int class, int func, int device) {
       enabled = 1;
       if (interrupting == 1)              /* if interrupt is pending */
         devpoll[device] = 10;             /* try to interrupt soon */
-      
+
     } else if (func == 016) {             /* reset interrupt mask */
       enabled = 0;
 
@@ -1092,7 +1092,7 @@ int devmt (int class, int func, int device) {
         } else
           unit[u].mtstat = 0x00C8;   /* Ready, Online, BOT */
       }
-      
+
       /* "select only" is ignored.  On a real tape controller, this
        blocks (I think) if the previous tape operation is in progress */
 
@@ -1276,12 +1276,12 @@ int devmt (int class, int func, int device) {
       }
       IOSKIP;
       break;
-        
+
     } else if (func == 02) {
       ready = 1;
       if (getcrs16(A) & 0x8000) {      /* status word 1 */
         datareg = unit[usel].mtstat;
-        
+
         /* if the tape was rewinding, return rewinding status once, then
            change it to BOT */
 
@@ -1413,7 +1413,9 @@ void initclock(ea_t datnowea) {
   unixtime = time(NULL);
   tms = localtime(&unixtime);
   datnow = tms->tm_year<<25 | (tms->tm_mon+1)<<21 | tms->tm_mday<<16 | ((tms->tm_hour*3600 + tms->tm_min*60 + tms->tm_sec)/4);
-  put32r0(datnow, datnowea);
+  if (! noclock) {
+    put32r0(datnow, datnowea);
+  }
 }
 
 
@@ -1438,7 +1440,7 @@ int devcp (int class, int func, int device) {
 
   case -1:
 
-    /* if -map is used, lookup DATNOW symbol and set the 32-bit 
+    /* if -map is used, lookup DATNOW symbol and set the 32-bit
        Primos time value (DATNOW+TIMNOW) */
 
     datnowea = 0;
@@ -1455,10 +1457,10 @@ int devcp (int class, int func, int device) {
       ;
 
     } else if (func == 01) {    /* ack PIC interrupt */
-      ; 
+      ;
 
     } else if (func == 02) {    /* stop LFC (IO.PNC DIAG) */
-      ; 
+      ;
 
     } else if (func == 04) {    /* does something on VCP during boot */
       ;
@@ -1581,7 +1583,7 @@ int devcp (int class, int func, int device) {
           previnstcount = gv.instcount;
           if (datnowea != 0)
             initclock(datnowea);
-        } 
+        }
         elapsedms = (tv.tv_sec-start_tv.tv_sec)*1000.0 + (tv.tv_usec-start_tv.tv_usec)/1000.0;
         targetticks = elapsedms/(-clkpic*clkrate/1000);
 #if 0
@@ -1595,7 +1597,7 @@ int devcp (int class, int func, int device) {
            available (no Primos maps), then we have to tick our way to
            the correct time.  In addition to lowering overhead, slower
            clock tick rates make catching up much faster.
-           
+
            When ticking faster, we need to be careful not to tick too
            fast, because that will cause timed events like disk I/O to
            timeout prematurely.  With rev 20 Primos, setting the
@@ -1812,7 +1814,7 @@ int devdisk (int class, int func, int device) {
       dc[dx].unit[u].modrecs = NULL;
     }
     return 0;
-      
+
   case 0:
     TRACE(T_INST|T_DIO, " OCP '%2o%2o\n", func, device);
     if (func == 016) {                /* reset interrupt */
@@ -2017,7 +2019,7 @@ int devdisk (int class, int func, int device) {
             }
             dmaaddr = ((getar16(REGDMX16+dmareg) & 3)<<16) | getar16(REGDMX16+dmareg+1);
             TRACE(T_INST|T_DIO,  " DMA channels: nch-1=%d, ['%o]='%o, ['%o]='%o, nwords=%d\n", dc[dx].dmanch, dc[dx].dmachan, swap16(regs.sym.regdmx[dmareg]), dc[dx].dmachan+1, dmaaddr, dmanw);
-            
+
             if (order == 5) {    /* read */
               if (getcrs16(MODALS) & 020)  /* mapped read */
                 if ((dmaaddr & 01777) || dmanw > 1024)
@@ -2078,7 +2080,7 @@ int devdisk (int class, int func, int device) {
         }
         TRACE(T_INST|T_DIO, " seek track %d, restore=%d, clear=%d\n", track, (m1 & 0100000) != 0, (m1 & 040000) != 0);
 #if 0
-        /* this has been disabled because SCSI drives sometimes seek to 
+        /* this has been disabled because SCSI drives sometimes seek to
            track 512 (special meaning in controller?) */
 
         if (track > dc[dx].unit[u].maxtrack) {

fp.h

@@ -40,6 +40,7 @@ http://tima-cmp.imag.fr/~guyot/Cours/Oparithm/english/Op_Ar2.htm
 
 inline void getdp (unsigned long long p, long long *frac64, int *exp32) {
 
+  TRACE(T_FP, "  getdp(%016llx)\n", p);
   *frac64 = p & 0xFFFFFFFFFFFF0000LL;  /* unpack fraction */
   *exp32 = (short) (p & 0xFFFFLL);     /* unpack SIGNED exponent */
 }
@@ -59,22 +60,29 @@ int prieee8(unsigned long long dp, double *d) {
   /* unpack Prime DPFP */
 
   getdp (dp, &frac64, &exp32);
+  TRACE(T_FP, "  prieee8: unpacked frac %016llx exp %08x\n", frac64, exp32);
 
   /* if negative, change to sign-magnitude */
 
   sign = 0;
   if (frac64 < 0) {
+    TRACE(T_FP, "  prieee8: changing to sign-magnitude\n");
 
     /* special case: negative power of 2 */
 
     if (frac64 == 0x8000000000000000LL) {
+      TRACE(T_FP, "  prieee8: frac is negative power of 2\n");
       exp32 += (1023-128);
       if (exp32 < 0 || exp32 > 0x7fe)
+      {
+        TRACE(T_FP, "  prieee8: exp %x out of range\n", exp32);
         return 0;
+      }
       frac64 |= ((long long)exp32 << 52);
       *d = *(double *)&frac64;
       return 1;
     } else {
+      TRACE(T_FP, "  prieee8: frac is just negative\n");
       sign = 0x8000000000000000LL;
       frac64 = -frac64;
     }
@@ -82,13 +90,15 @@ int prieee8(unsigned long long dp, double *d) {
   /* special case: zero */
 
   } else if (frac64 == 0) {
+    TRACE(T_FP, "  prieee8: frac is 0\n");
     *d = 0.0;
     return 1;
-  } 
+  }
 
   /* normalize positive fraction until bit 2 is 1 */
 
   while ((frac64 & 0x4000000000000000LL) == 0) {
+    TRACE(T_FP, "  prieee8: normalizing positive fraction\n");
     frac64 = frac64 << 1;
     exp32--;
   }
@@ -98,7 +108,10 @@ int prieee8(unsigned long long dp, double *d) {
   exp32 += (1023-128) - 1;
 #if 1
   if (exp32 < 0 || exp32 > 0x7fe)
+  {
+    TRACE(T_FP, "  prieee8: exponent %x out of range\n", exp32);
     return 0;
+  }
 #else
   if (exp32 < 0) {
     *d = 0.0;
@@ -113,6 +126,7 @@ int prieee8(unsigned long long dp, double *d) {
   /* pack into an IEEE DPFP, losing the leading 1 bit in the process */
 
   frac64 = sign | ((long long)exp32 << 52) | ((frac64 >> 10) & 0xfffffffffffffLL);
+  TRACE(T_FP, "  prieee8: packed ieee dpfp %016llx\n", frac64);
   *d = *(double *)&frac64;
   return 1;
 }
@@ -134,7 +148,7 @@ retry:
   neg = frac64 < 0;
   exp32 = (frac64 >> 52) & 0x7ff;
   frac64 &= 0xfffffffffffffLL;
-  //printf("dp=%llx, neg=%d, frac64=%llx, exp32=%d, \n", *(long long *)dp, neg, frac64, exp32);
+  TRACE(T_FP, "d=%016llx, neg=%x, frac64=%016llx, exp32=%08x, \n", (long long)d, neg, frac64, exp32);
 
   /* special case: NaN & +-infinity */
 
@@ -159,12 +173,21 @@ retry:
      and subnormal */
 
   if (exp32 != 0)           /* typical IEEE normalized */
+  {
+    TRACE(T_FP, "  ieeepr8: is normalized\n");
     frac64 |= 0x10000000000000LL;
-  else if (frac64 == 0) {   /* IEEE +-0.0 (zero exp+frac) */
+  }
+  else if (frac64 == 0)     /* IEEE +-0.0 (zero exp+frac) */
+  {
+    TRACE(T_FP, "  ieeepr8: zero exp and frac\n");
     *p = 0;                 /* IEEE and Prime zero are the same */
     return okay;
-  } else
+  }
+  else
+  {
+    TRACE(T_FP, "  ieeepr8: subnormal value\n");
       ;                     /* subnormal: no hidden 1 bit */
+  }
 
   /* adjust exponent, change sign-magnitude to 2's complement,
      and shift fraction into Prime placement (high 48 bits) */
@@ -173,12 +196,14 @@ retry:
   if (neg)
     frac64 = -frac64;
   frac64 <<= 10;
+  TRACE(T_FP, "  ieeepr8: de-biased prime-ised frac %016llx exp %08x\n", frac64, exp32);
 
   /* normalize Prime DPFP */
 
   while ((frac64 ^ (frac64 << 1)) >= 0) {
     frac64 = frac64 << 1;
     exp32--;
+    TRACE(T_FP, "  ieeepr8: normalized prime frac %016llx exp %08x\n", frac64, exp32);
   }
 
 #if 0
@@ -204,8 +229,11 @@ retry:
 
   if (round)
     if ((frac64 & 0x8000) && ((frac64 & 0x7fffffffffff0000LL) !=  0x7fffffffffff0000LL))
+    {
       /* XXX: should this be a subtract for negative numbers? */
       frac64 += 0x10000;
+      TRACE(T_FP, "  ieeepr8: rounded frac %016llx\n", frac64);
+    }
 
   *p = swap64((frac64 & 0xffffffffffff0000LL) | (exp32 & 0xffff));
   return okay;
@@ -260,6 +288,7 @@ unsigned long long dfcm (unsigned long long dp, int *oflow) {
   CLEARC;
   *oflow = 0;
   getdp(dp, &frac64, &exp32);
+  TRACE(T_FP, "  dfcm: unpacked frac %016llx exp %08x\n", frac64, exp32);
   if (frac64 != 0) {                          /* can't normalize zero */
     if (frac64 == 0x8000000000000000LL) {     /* overflow case? */
       frac64 = 0x4000000000000000LL;          /* complement power of 2 */
@@ -290,6 +319,7 @@ unsigned long long norm(unsigned long long dp, int *oflow) {
 
   *oflow = 0;
   getdp(dp, &frac64, &exp32);
+  TRACE(T_FP, "  norm: unpacked frac %016llx exp %08x\n", frac64, exp32);
   while ((frac64 ^ (frac64 << 1)) >= 0) {
     frac64 = frac64 << 1;
     exp32--;
@@ -314,11 +344,16 @@ unsigned long long frn(unsigned long long dp, int *oflow) {
 
   *oflow = 0;
   getdp(dp, &frac64, &exp32);
+  TRACE(T_FP, "  frn: unpacked frac %016llx exp %08x\n", frac64, exp32);
   if (frac64 == 0)
+  {
+    TRACE(T_FP, "  frn: returning 0\n");
     return 0;
+  }
   else {
     doround1 = ((frac64 & 0x18000000000LL) != 0);
     doround2 = ((frac64 &  0x8000000000LL) != 0) && ((frac64 & 0x7FFFFF0000LL) != 0);
+    TRACE(T_FP, "  frn: doround1 %x doround2 %x\n", doround1, doround2);
     if (doround1 || doround2) {
       frac64 &= 0xFFFFFF0000000000LL;
       if (frac64 != 0x7FFFFF0000000000LL)
@@ -329,8 +364,10 @@ unsigned long long frn(unsigned long long dp, int *oflow) {
       }
       frac64 |= (exp32 & 0xFFFF);
       frac64 = norm(frac64, oflow);
+      TRACE(T_FP, "  frn: rounded frac %016llx\n", frac64);
       return frac64;
     }
+    TRACE(T_FP, "  frn: dp %016llx\n", dp);
     return dp;
   }
 }
@@ -356,26 +393,37 @@ int fcs (unsigned long long fac, int fop) {
   fop = fop & 0xffffff00;
   if (fop == 0)                                      /* fix dirty zero */
     fopexp = 0;
+  TRACE(T_FP, "  fcs: FAC: %016llx %04x; op: %016llx %04x\n", templ, facexp, fop, fopexp);
   if ((templ & 0x80000000) == (fop & 0x80000000)) {  /* compare signs */
     if (facexp == fopexp)                            /* compare exponents */
       if (templ == fop) {                            /* compare fractions */
+        TRACE(T_FP, "  fcs: frac cmp returning eq / skip 1\n");
         SETEQ;
         return 1;
       } else if (templ < fop) {                      /* compare fractions */
+        TRACE(T_FP, "  fcs: frac cmp returning lt / skip 2\n");
         SETLT;                                       /* FAC < operand */
         return 2;
-      } else
+      } else {
+        TRACE(T_FP, "  fcs: frac cmp returning gt / skip 0\n");
         return 0;                                    /* FAC > operand */
+      }
     else if (facexp < fopexp) {                      /* compare exponents */
+      TRACE(T_FP, "  fcs: exp cmp returning lt / skip 2\n");
       SETLT;                                         /* FAC < operand */
       return 2;
-    } else
+    } else {
+      TRACE(T_FP, "  fcs: exp cmp returning gt / skip 0\n");
       return 0;
+    }
   } else if (templ & 0x80000000) {
+    TRACE(T_FP, "  fcs: sign cmp returning lt / skip 2\n");
     SETLT;                                           /* FAC < operand */
     return 2;
-  } else
+  } else {
+    TRACE(T_FP, "  fcs: sign cmp returning gt / skip 0\n");
     return 0;                                        /* FAC > operand */
+  }
 }
 
 
@@ -386,7 +434,7 @@ int fcs (unsigned long long fac, int fop) {
 
    NOTE: This code doesn't pass Prime diagnostics for higher model
    CPU's, I'm guessing because comparison is implemented as subtract,
-   and we can't do that because numbers with huge exponents (and 
+   and we can't do that because numbers with huge exponents (and
    Prime ASCII characters in the DAC) won't convert to IEEE.
 */
 
@@ -404,27 +452,35 @@ int dfcs (unsigned long long fac, long long fop) {
   fop = fop & 0xffffffffffff0000LL;
   if (fop == 0)                                      /* fix dirty zero */
     fopexp = 0;
-#if 0
+  TRACE(T_FP, "  dfcs: FAC: %016llx %04x; op: %016llx %04x\n", templl, facexp, fop, fopexp);
-  printf("dfcs: FAC: %016llx %04x; op: %016llx %04x\n", templl, facexp, fop, fopexp);
-#endif
   if ((templl & 0x8000000000000000LL) == (fop & 0x8000000000000000LL)) {  /* compare signs */
     if (facexp == fopexp)                            /* compare exponents */
       if (templl == fop) {                           /* compare fractions */
+        TRACE(T_FP, "  dfcs: frac cmp returning eq / skip 1\n");
         SETEQ;
         return 1;
       } else if (templl < fop) {                     /* compare fractions */
+        TRACE(T_FP, "  dfcs: frac cmp returning lt / skip 2\n");
         SETLT;                                       /* FAC < operand */
         return 2;
-      } else
+      } else {
+        TRACE(T_FP, "  dfcs: frac cmp returning gt / skip 0\n");
         return 0;                                    /* FAC > operand */
+      }
     else if (facexp < fopexp) {                      /* compare exponents */
+      TRACE(T_FP, "  dfcs: exp cmp returning lt / skip 2\n");
       SETLT;                                         /* FAC < operand */
       return 2;
-    } else
+    } else {
+      TRACE(T_FP, "  dfcs: exp cmp returning eq / skip 1\n");
       return 0;
+    }
   } else if (templl & 0x8000000000000000LL) {
+    TRACE(T_FP, "  dfcs: sign cmp returning lt / skip 2\n");
     SETLT;                                           /* FAC < operand */
     return 2;
-  } else
+  } else {
+    TRACE(T_FP, "  dfcs: sign cmp returning gt / skip 0\n");
     return 0;                                        /* FAC > operand */
+  }
 }

util/utextp.c

@@ -1,5 +1,5 @@
 /* utextp.c, Jim Wilcoxson, March 16, 2005
-   Reads a Unix text file and converts it to a compressed Prime text file. 
+   Reads a Unix text file and converts it to a compressed Prime text file.
    This means:
    - turn high bit on
    - expand Unix tabs to spaces
@@ -29,7 +29,7 @@ main () {
     else {                    /* not a space character */
       while (space) {         /* dump held-back spaces first */
 	if (space < 3) {      /* write regular spaces */
-	  putchar(' ');
+	  putchar(0240);
 	  space--;
 	  n++;
 	} else {              /* write compressed spaces */