* sim/ucsim/cmd.src/cmdutil.cc: NUL device is detected as CG_FILE type
[fw/sdcc] / src / pic / device.c
index ce4746aebdf440fd449ca050dce1348ad7b23f8d..36c0caf0e70a639aae4bf40fece02bf99661c3f4 100644 (file)
 #include "ralloc.h"
 #include "device.h"
 
-#if defined(__BORLANDC__) || defined(_MSC_VER)
-#define STRCASECMP stricmp
-#define STRNCASECMP strnicmp
-#else
-#define STRCASECMP strcasecmp
-#define STRNCASECMP strncasecmp
-#endif
-
 extern int Gstack_base_addr;
 extern int Gstack_size;
 
@@ -49,7 +41,6 @@ static int num_of_supported_PICS = 0;
 static PIC_device *pic=NULL;
 
 int maxRAMaddress = 0;
-AssignedMemory *finalMapping=NULL;
 
 #define CONFIG_WORD_ADDRESS 0x2007
 #define CONFIG2_WORD_ADDRESS 0x2008
@@ -62,9 +53,7 @@ AssignedMemory *finalMapping=NULL;
 
 static unsigned int config_word = DEFAULT_CONFIG_WORD;
 static unsigned int config2_word = DEFAULT_CONFIG2_WORD;
-
-extern int pic14_is_shared (regs *reg);
-extern void emitSymbolToFile (FILE *of, const char *name, const char *section_type, int size, int addr, int useEQU, int globalize);
+static memRange *rangeRAM = NULL;
 
 
 /* parse a value from the configuration file */
@@ -113,15 +102,12 @@ static char *sanitise_processor_name(char *name)
        if (name == NULL)
                return NULL;
        
-       if (STRNCASECMP(proc_pos, "pic16", 5) == 0)
-               proc_pos += 5;
-
-       else if (STRNCASECMP(proc_pos, "p16", 3) == 0)
+       if (STRNCASECMP(proc_pos, "pic", 3) == 0)
                proc_pos += 3;
+
+       else if (tolower(*proc_pos) == 'p')
+               proc_pos += 1;
                                
-       else if (STRNCASECMP(proc_pos, "16", 2) == 0)
-               proc_pos += 2;
-                                       
        return proc_pos;
 }
 
@@ -133,14 +119,8 @@ static PIC_device *create_pic(char *pic_name, int maxram, int bankmsk, int confs
        char *simple_pic_name = sanitise_processor_name(pic_name);
        
        new_pic = Safe_calloc(1, sizeof(PIC_device));
-       new_pic->name[0] = Safe_calloc(strlen(simple_pic_name)+3, sizeof(char));
-       sprintf(new_pic->name[0], "16%s", simple_pic_name);
-       new_pic->name[1] = Safe_calloc(strlen(simple_pic_name)+4, sizeof(char));
-       sprintf(new_pic->name[1], "p16%s", simple_pic_name);
-       new_pic->name[2] = Safe_calloc(strlen(simple_pic_name)+6, sizeof(char));
-       sprintf(new_pic->name[2], "pic16%s", simple_pic_name);
-       new_pic->name[3] = Safe_calloc(strlen(simple_pic_name)+1, sizeof(char));
-       strcpy(new_pic->name[3], simple_pic_name);
+       new_pic->name = Safe_calloc(strlen(simple_pic_name)+1, sizeof(char));
+       strcpy(new_pic->name, simple_pic_name);
                        
        new_pic->defMaxRAMaddrs = maxram;
        new_pic->bankMask = bankmsk;
@@ -150,6 +130,8 @@ static PIC_device *create_pic(char *pic_name, int maxram, int bankmsk, int confs
        new_pic->dataMemSize = data;
        new_pic->eepromMemSize = eeprom;
        new_pic->ioPins = io;
+
+       new_pic->ram = rangeRAM;
        
        Pics[num_of_supported_PICS] = new_pic;
        num_of_supported_PICS++;
@@ -161,23 +143,24 @@ static PIC_device *create_pic(char *pic_name, int maxram, int bankmsk, int confs
 /* mark some registers as being duplicated across banks */
 static void register_map(int num_words, char word[SPLIT_WORDS_MAX][PIC14_STRING_LEN])
 {
-       memRange r;
+       memRange *r;
        int pcount;
        
        if (num_words < 3) {
                fprintf(stderr, "WARNING: not enough values in %s regmap directive\n", DEVICE_FILE_NAME);
                return;
        }
-       
-       r.alias = parse_config_value(word[1]);
 
        for (pcount = 2; pcount < num_words; pcount++) {
-           
-               r.start_address = parse_config_value(word[pcount]);
-               r.end_address = parse_config_value(word[pcount]);
-               r.bank = (r.start_address >> 7) & 3;
+               r = Safe_calloc(1, sizeof(memRange));
                
-               addMemRange(&r, 1);
+               r->start_address = parse_config_value(word[pcount]);
+               r->end_address = parse_config_value(word[pcount]);
+               r->alias = parse_config_value(word[1]);
+               r->bank = (r->start_address >> 7) & 3;
+               // add memRange to device entry for future lookup (sharebanks)
+               r->next = rangeRAM;
+               rangeRAM = r;
        }
 }
 
@@ -185,19 +168,24 @@ static void register_map(int num_words, char word[SPLIT_WORDS_MAX][PIC14_STRING_
 /* define ram areas - may be duplicated across banks */
 static void ram_map(int num_words, char word[SPLIT_WORDS_MAX][PIC14_STRING_LEN])
 {
-       memRange r;
+       memRange *r;
        
        if (num_words < 4) {
                fprintf(stderr, "WARNING: not enough values in %s memmap directive\n", DEVICE_FILE_NAME);
                return;
        }
+
+       r = Safe_calloc(1, sizeof(memRange));
+       //fprintf (stderr, "%s: %s %s %s\n", __FUNCTION__, word[1], word[2], word[3]);
        
-       r.start_address = parse_config_value(word[1]);
-       r.end_address = parse_config_value(word[2]);
-       r.alias = parse_config_value(word[3]);
-       r.bank = (r.start_address >> 7) & 3;
+       r->start_address = parse_config_value(word[1]);
+       r->end_address = parse_config_value(word[2]);
+       r->alias = parse_config_value(word[3]);
+       r->bank = (r->start_address >> 7) & 3;
                
-       addMemRange(&r, 0);
+       // add memRange to device entry for future lookup (sharebanks)
+       r->next = rangeRAM;
+       rangeRAM = r;
 }
 
 extern set *includeDirsSet;
@@ -228,8 +216,8 @@ static PIC_device *find_device(char *pic_name)
        char filename[512];
        int len = 512;
        
+       /* allow abbreviations of the form "f877" - convert to "16f877" */
        simple_pic_name = sanitise_processor_name(pic_name);
-       
        num_of_supported_PICS = 0;
        
        /* open the piclist file */
@@ -409,50 +397,8 @@ static PIC_device *find_device(char *pic_name)
        return NULL;
 }
 
-void addMemRange(memRange *r, int type)
-{
-       int i;
-       int alias = r->alias;
-       
-       if (maxRAMaddress < 0) {
-               fprintf(stderr, "missing maxram setting in %s\n", DEVICE_FILE_NAME);
-               return;
-       }
-       
-       do {
-               for (i=r->start_address; i<= r->end_address; i++) {
-                       if ((i|alias) <= maxRAMaddress) {
-                               /* if we haven't seen this address before, enter it */
-                               if (!finalMapping[i | alias].isValid) {
-                               finalMapping[i | alias].isValid = 1;
-                               finalMapping[i | alias].alias = r->alias;
-                               finalMapping[i | alias].bank  = r->bank;
-                               if(type) {
-                                       /* hack for now */
-                                       finalMapping[i | alias].isSFR  = 1;
-                               } else {
-                                       finalMapping[i | alias].isSFR  = 0;
-                               }
-                               }
-                       } else {
-                               fprintf(stderr, "WARNING: %s:%s memory at 0x%x is beyond max ram = 0x%x\n",
-                                       __FILE__,__FUNCTION__,(i|alias), maxRAMaddress);
-                       }
-               }
-               
-               /* Decrement alias */
-               if (alias) {
-                       alias -= ((alias & (alias - 1)) ^ alias);
-               } else {
-                       alias--;
-               }
-               
-       } while (alias >= 0);
-}
-
 void setMaxRAM(int size)
 {
-       int i;
        maxRAMaddress = size;
        
        if (maxRAMaddress < 0) {
@@ -460,17 +406,6 @@ void setMaxRAM(int size)
                        maxRAMaddress, DEVICE_FILE_NAME);
                return;
        }
-       
-       finalMapping = Safe_calloc(1+maxRAMaddress,
-               sizeof(AssignedMemory));
-       
-       /* Now initialize the finalMapping array */
-       
-       for(i=0; i<=maxRAMaddress; i++) {
-               finalMapping[i].reg = NULL;
-               finalMapping[i].isValid = 0;
-               finalMapping[i].bank = (i>>7);
-       }
 }
 
 /*-----------------------------------------------------------------*
@@ -501,174 +436,31 @@ int REGallBanks(regs *reg)
 }
 
 /*-----------------------------------------------------------------*
-*-----------------------------------------------------------------*/
-
-int isSFR(int address)
-{
-       
-       if( (address > maxRAMaddress) || !finalMapping[address].isSFR)
-               return 0;
-       
-       return 1;
-       
-}
-
-/*
-*  dump_map -- debug stuff
-*/
-
-void dump_map(void)
-{
-       int i;
-       
-       for(i=0; i<=maxRAMaddress; i++) {
-               //fprintf(stdout , "addr 0x%02x is %s\n", i, ((finalMapping[i].isValid) ? "valid":"invalid"));
-               
-               if(finalMapping[i].isValid) {
-                       fprintf(stderr,"addr: 0x%02x",i);
-                       if(finalMapping[i].isSFR)
-                               fprintf(stderr," isSFR");
-                       if(finalMapping[i].reg) 
-                               fprintf( stderr, "  reg %s", finalMapping[i].reg->name);
-                       fprintf(stderr, "\n");
-               }
-       }
-       
-}
-
-void dump_sfr(FILE *of)
-{
-#if 0
-       int start=-1;
-       int bank_base;
-       static int udata_flag=0;
-#endif
-       int addr=0;
-       
-       //dump_map();   /* display the register map */
-       //fprintf(stdout,";dump_sfr  \n");
-       if (maxRAMaddress < 0) {
-               fprintf(stderr, "missing maxram setting in %s\n", DEVICE_FILE_NAME);
-               return;
-       }
-       
-       for (addr = 0; addr <= maxRAMaddress; addr++)
-       {
-               regs *reg = finalMapping[addr].reg;
-               
-               if (reg && !reg->isEmitted)
-               {
-                 if (pic14_options.isLibrarySource && pic14_is_shared (reg))
-                 {
-                   /* rely on external declarations for the non-fixed stack */
-                   /* Update: We always emit the STACK symbols into a
-                    * udata_shr section, so no extern declaration is
-                    * required. */
-                   //fprintf (of, "\textern\t%s\n", reg->name);
-                 } else {
-                   emitSymbolToFile (of, reg->name, "udata", reg->size, reg->isFixed ? reg->address : -1, 0, pic14_is_shared (reg));
-                 }
-                 
-                 reg->isEmitted = 1;
-               }
-       } // for
-
-#if 0
-       do {
-
-               if(finalMapping[addr].reg && !finalMapping[addr].reg->isEmitted) {
-                       
-                       if(start<0)
-                               start = addr;
-               } else {
-                       if(start>=0) {
-                               
-                               /* clear the lower 7-bits of the start address of the first
-                               * variable declared in this bank. The upper bits for the mid
-                               * range pics are the bank select bits.
-                               */
-                               
-                               bank_base = start & 0xfff8;
-                               
-                               /* The bank number printed in the cblock comment tacitly
-                               * assumes that the first register in the contiguous group
-                               * of registers represents the bank for the whole group */
-                               
-                               if ( (start != addr) && (!udata_flag) ) {
-                                       udata_flag = 1;
-                                       //fprintf(of,"\tudata\n");
-                               }
-                               
-                               for( ; start < addr; start++) {
-                                       if((finalMapping[start].reg) && 
-                                               (!finalMapping[start].reg->isEmitted) &&
-                                               (!finalMapping[start].instance) && 
-                                               (!finalMapping[start].isSFR)) {
-                                               
-                                               if (finalMapping[start].reg->isFixed) {
-                                                       unsigned i;
-                                                       for (i=0; i<finalMapping[start].reg->size; i++) {
-                                                               fprintf(of,"%s\tEQU\t0x%04x\n",
-                                                                       finalMapping[start].reg->name, 
-                                                                       finalMapping[start].reg->address+i);
-                                                       }
-                                               } else {
-                                                       emitSymbolToFile (of, finalMapping[start].reg->name, finalMapping[start].reg->size);
-#if 0
-                                                       fprintf(of,"%s\tres\t%i\n",
-                                                               finalMapping[start].reg->name, 
-                                                               finalMapping[start].reg->size);
-#endif
-                                               }
-                                               finalMapping[start].reg->isEmitted = 1;
-                                       }
-                               }
-                               
-                               start = -1;
-                       }
-                       
-               }
-               
-               addr++;
-               
-       } while(addr <= maxRAMaddress);
-
-
-#endif
-}
-
-/*-----------------------------------------------------------------*
-*  void list_valid_pics(int ncols, int list_alias)
-*
-* Print out a formatted list of valid PIC devices
-*
-* ncols - number of columns in the list.
-*
-* list_alias - if non-zero, print all of the supported aliases
-*              for a device (e.g. F84, 16F84, etc...)
-*-----------------------------------------------------------------*/
-void list_valid_pics(int ncols, int list_alias)
+ *  void list_valid_pics(int ncols, int list_alias)
+ *
+ * Print out a formatted list of valid PIC devices
+ *
+ * ncols - number of columns in the list.
+ *
+ * list_alias - if non-zero, print all of the supported aliases
+ *              for a device (e.g. F84, 16F84, etc...)
+ *-----------------------------------------------------------------*/
+void list_valid_pics(int ncols)
 {
        int col=0,longest;
-       int i,j,k,l;
-       int max_alias = 1;
+       int i,k,l;
        
        if (num_of_supported_PICS == 0)
                find_device(NULL);          /* load all the definitions */
        
-       if(list_alias)
-               max_alias = PROCESSOR_NAMES;
-       
        /* decrement the column number if it's greater than zero */
        ncols = (ncols > 1) ? ncols-1 : 4;
        
        /* Find the device with the longest name */
        for(i=0,longest=0; i<num_of_supported_PICS; i++) {
-               for(j=0; j<max_alias; j++) {
-                       k = strlen(Pics[i]->name[j]);
-                       if(k>longest)
-                               longest = k;
-               }
+               k = strlen(Pics[i]->name);
+               if(k>longest)
+                       longest = k;
        }
        
 #if 1
@@ -681,8 +473,8 @@ void list_valid_pics(int ncols, int list_alias)
        fprintf(stderr, "-----------------------------------------------------\n");
        
        for(i=0;  i < num_of_supported_PICS; i++) {
-               fprintf(stderr,"  %s", Pics[i]->name[0]);
-               l = longest + 2 - strlen(Pics[i]->name[0]);
+               fprintf(stderr,"  %s", Pics[i]->name);
+               l = longest + 2 - strlen(Pics[i]->name);
                for(k=0; k<l; k++)
                        fputc(' ',stderr);
        
@@ -701,21 +493,17 @@ void list_valid_pics(int ncols, int list_alias)
        fprintf(stderr, "\nPIC14 processors supported:\n");
        for(i=0;  i < num_of_supported_PICS; i++) {
                        
-               for (j = 0; j<max_alias; j++) {
-                       
-                       fprintf(stderr,"%s", Pics[i]->name[j]);
-                       if(col<ncols) {
-                               l = longest + 2 - strlen(Pics[i]->name[j]);
-                               for(k=0; k<l; k++)
-                                       fputc(' ',stderr);
+               fprintf(stderr,"%s", Pics[i]->name);
+               if(col<ncols) {
+                       l = longest + 2 - strlen(Pics[i]->name);
+                       for(k=0; k<l; k++)
+                               fputc(' ',stderr);
                                
-                               col++;
+                       col++;
                                
-                       } else {
-                               fputc('\n',stderr);
-                               col = 0;
-                       }
-                       
+               } else {
+                       fputc('\n',stderr);
+                       col = 0;
                }
                
        }
@@ -727,19 +515,27 @@ void list_valid_pics(int ncols, int list_alias)
 /*-----------------------------------------------------------------*
 *  
 *-----------------------------------------------------------------*/
-void init_pic(char *pic_type)
+PIC_device *init_pic(char *pic_type)
 {
+       char long_name[PIC14_STRING_LEN];
+       
        pic = find_device(pic_type);
        
-       if(!pic) {
-               if(pic_type)
-                       fprintf(stderr, "'%s' was not found.\n", pic_type);
-               else
-                       fprintf(stderr, "No processor has been specified (use -pPROCESSOR_NAME)\n");
+       if (pic == NULL) {
+               /* check for shortened "16xxx" form */
+               sprintf(long_name, "16%s", pic_type);
+               pic = find_device(long_name);
+               if (pic == NULL) {
+                       if(pic_type != NULL && pic_type[0] != '\0')
+                               fprintf(stderr, "'%s' was not found.\n", pic_type);
+                       else
+                               fprintf(stderr, "No processor has been specified (use -pPROCESSOR_NAME)\n");
                
-               list_valid_pics(7,0);
-               exit(1);
+                       list_valid_pics(7);
+                       exit(1);
+               }
        }
+       return pic;
 }
 
 /*-----------------------------------------------------------------*
@@ -763,15 +559,13 @@ char *processor_base_name(void)
        if(!pic)
                return NULL;
        
-       return pic->name[1];
+       return pic->name;
 }
 
 /*-----------------------------------------------------------------*
 *-----------------------------------------------------------------*/
 int validAddress(int address, int reg_size)
 {
-       int i;
-       
        if (maxRAMaddress < 0) {
                fprintf(stderr, "missing maxram setting in %s\n", DEVICE_FILE_NAME);
                return 0;
@@ -781,15 +575,12 @@ int validAddress(int address, int reg_size)
        if(address + (reg_size - 1) > maxRAMaddress)
                return 0;
        
-       for (i=0; i<reg_size; i++)
-               if(!finalMapping[address + i].isValid || 
-                       finalMapping[address+i].reg ||
-                       finalMapping[address+i].isSFR )
-                       return 0;
-               
-               return 1;
+       return 1;
 }
 
+#if 0
+/* The following code should be (and is) implemented in the linker. */
+
 /*-----------------------------------------------------------------*
 *-----------------------------------------------------------------*/
 void mapRegister(regs *reg)
@@ -810,6 +601,8 @@ void mapRegister(regs *reg)
        
        for(i=0; i<reg->size; i++) {
                
+               assert(reg->address >= 0 && reg->address < maxRAMaddress);
+               
                alias = finalMapping[reg->address].alias;
                reg->alias = alias;
                
@@ -850,14 +643,11 @@ int assignRegister(regs *reg, int start_address)
                        return reg->address;
                }
                
-               if( isSFR(reg->address)) {
-                       mapRegister(reg);
-                       return reg->address;
+               if (getenv("SDCCPICDEBUG")) {
+                       fprintf(stderr, "WARNING: Ignoring Out of Range register assignment at fixed address %d, %s\n",
+                           reg->address, reg->name);
                }
                
-               fprintf(stderr, "WARNING: Ignoring Out of Range register assignment at fixed address %d, %s\n",
-                   reg->address, reg->name);
-               
        } else {
                
        /* This register does not have a fixed address requirement
@@ -931,18 +721,21 @@ void assignRelocatableRegisters(set *regset, int used)
        }
        
 }
+#endif
 
+/* Keep track of whether we found an assignment to the __config words. */
+static int pic14_hasSetConfigWord = 0;
 
 /*-----------------------------------------------------------------*
-*  void assignConfigWordValue(int address, int value)
-*
-* Most midrange PICs have one config word at address 0x2007.
-* Newer PIC14s have a second config word at address 0x2008.
-* This routine will assign values to those addresses.
-*
-*-----------------------------------------------------------------*/
+ *  void assignConfigWordValue(int address, int value)
+ *
+ * Most midrange PICs have one config word at address 0x2007.
+ * Newer PIC14s have a second config word at address 0x2008.
+ * This routine will assign values to those addresses.
+ *
+ *-----------------------------------------------------------------*/
 
-void assignConfigWordValue(int address, int value)
+void pic14_assignConfigWordValue(int address, int value)
 {
        if (CONFIG_WORD_ADDRESS == address)
                config_word = value;
@@ -951,16 +744,44 @@ void assignConfigWordValue(int address, int value)
                config2_word = value;
        
        //fprintf(stderr,"setting config word 0x%x to 0x%x\n", address, value);
-       
+       pic14_hasSetConfigWord = 1;
 }
+
 /*-----------------------------------------------------------------*
-* int getConfigWord(int address)
-*
-* Get the current value of a config word.
-*
-*-----------------------------------------------------------------*/
+ * int pic14_emitConfigWord (FILE * vFile)
+ * 
+ * Emit the __config directives iff we found a previous assignment
+ * to the config word.
+ *-----------------------------------------------------------------*/
+extern char *iComments2;
+int pic14_emitConfigWord (FILE * vFile)
+{
+  if (pic14_hasSetConfigWord)
+  {
+    fprintf (vFile, "%s", iComments2);
+    fprintf (vFile, "; config word \n");
+    fprintf (vFile, "%s", iComments2);
+    if (pic14_getHasSecondConfigReg())
+    {
+      fprintf (vFile, "\t__config _CONFIG1, 0x%x\n", pic14_getConfigWord(0x2007));
+      fprintf (vFile, "\t__config _CONFIG2, 0x%x\n", pic14_getConfigWord(0x2008));
+    }
+    else
+      fprintf (vFile, "\t__config 0x%x\n", pic14_getConfigWord(0x2007));
+
+    return 1;
+  }
+  return 0;
+}
 
-int getConfigWord(int address)
+/*-----------------------------------------------------------------*
+ * int pic14_getConfigWord(int address)
+ *
+ * Get the current value of a config word.
+ *
+ *-----------------------------------------------------------------*/
+
+int pic14_getConfigWord(int address)
 {
        switch (address)
        {
@@ -978,7 +799,7 @@ int getConfigWord(int address)
 /*-----------------------------------------------------------------*
 *  
 *-----------------------------------------------------------------*/
-unsigned getMaxRam(void)
+unsigned pic14_getMaxRam(void)
 {
        return pic->defMaxRAMaddrs;
 }
@@ -988,7 +809,7 @@ unsigned getMaxRam(void)
 *  int getHasSecondConfigReg(void) - check if the device has a 
 *  second config register, rather than just one.
 *-----------------------------------------------------------------*/
-int getHasSecondConfigReg(void)
+int pic14_getHasSecondConfigReg(void)
 {
        if(!pic)
                return 0;
@@ -997,29 +818,118 @@ int getHasSecondConfigReg(void)
 }
 
 /*-----------------------------------------------------------------*
- * Query the size of the sharebank of the selected device.
- * FIXME: Currently always returns 16.
+ * True iff the device has memory aliased in every bank.
+ * If true, low and high will be set to the low and high address
+ * occupied by the (last) sharebank found.
  *-----------------------------------------------------------------*/
-int pic14_getSharebankSize(void)
+int pic14_hasSharebank(int *low, int *high, int *size)
 {
-       return 16;
+       memRange *r;
+
+       assert(pic);
+       r = pic->ram;
+
+       while (r) {
+           //fprintf (stderr, "%s: region %x..%x, bank %x, alias %x, pic->bankmask %x, min_size %d\n",  __FUNCTION__, r->start_address, r->end_address, r->bank, r->alias, pic->bankMask, size ? *size : 0);
+           // find sufficiently large shared region
+           if ((r->alias == pic->bankMask)
+                   && (r->end_address != r->start_address) // ignore SFRs
+                   && (!size || (*size <= (r->end_address - r->start_address + 1))))
+           {
+               if (low) *low = r->start_address;
+               if (high) *high = r->end_address;
+               if (size) *size = r->end_address - r->start_address + 1;
+               return 1;
+           } // if
+           r = r->next;
+       } // while
+
+       if (low) *low = 0x0;
+       if (high) *high = 0x0;
+       if (size) *size = 0x0;
+       //fprintf (stderr, "%s: no shared bank found\n", __FUNCTION__);
+       return 0;
 }
 
-/*-----------------------------------------------------------------*
- * Query the highest byte address occupied by the sharebank of the
- * selected device.
- * FIXME: Currently always returns 0x7f.
- * THINK: Might not be needed, if we assign all shareable objects to
- *        a `udata_shr' section and let the linker do the rest...
- * Tried it, but yields `no target memory available' for pic16f877...
- *-----------------------------------------------------------------*/
-int pic14_getSharebankAddress(void)
+/*
+ * True iff the memory region [low, high] is aliased in all banks.
+ */
+int pic14_isShared(int low, int high)
 {
-       int sharebankAddress = 0x7f;
-       /* If total RAM is less than 0x7f as with 16f84 then reduce
-        * sharebankAddress to fit */
-       if ((unsigned)sharebankAddress > getMaxRam())
-               sharebankAddress = (int)getMaxRam();
-       return sharebankAddress;
+       memRange *r;
+
+       assert(pic);
+       r = pic->ram;
+
+       while (r) {
+           //fprintf (stderr, "%s: region %x..%x, bank %x, alias %x, pic->bankmask %x\n", __FUNCTION__, r->start_address, r->end_address, r->bank, r->alias, pic->bankMask);
+           if ((r->alias == pic->bankMask) && (r->start_address <= low) && (r->end_address >= high)) {
+               return 1;
+           } // if
+           r = r->next;
+       } // while
+
+       return 0;
 }
 
+/*
+ * True iff all RAM is aliased in all banks (no BANKSELs required except for
+ * SFRs).
+ */
+int pic14_allRAMShared(void)
+{
+       memRange *r;
+
+       assert(pic);
+       r = pic->ram;
+
+       while (r) {
+           if (r->alias != pic->bankMask) return 0;
+           r = r->next;
+       } // while
+       
+       return 1;
+}
+
+/*
+ * True iff the pseudo stack is a sharebank --> let linker place it.
+ * [low, high] denotes a size byte long block of (shared or banked)
+ * memory to be used.
+ */
+int pic14_getSharedStack(int *low, int *high, int *size)
+{
+    int haveShared;
+    int l, h, s;
+
+    s = options.stack_size ? options.stack_size : 0x10;
+    haveShared = pic14_hasSharebank(&l, &h, &s);
+    if ((options.stack_loc != 0) || !haveShared)
+    {
+       // sharebank not available or not to be used
+       s = options.stack_size ? options.stack_size : 0x10;
+       l = options.stack_loc ? options.stack_loc : 0x20;
+       h = l + s - 1;
+       if (low) *low = l;
+       if (high) *high = h;
+       if (size) *size = s;
+       // return 1 iff [low, high] is present in all banks
+       //fprintf(stderr, "%s: low %x, high %x, size %x, shared %d\n", __FUNCTION__, l, h, s, pic14_isShared(l, h));
+       return (pic14_isShared(l, h));
+    } else {
+       // sharebanks available for use by the stack
+       if (options.stack_size) s = options.stack_size;
+       else if (!s || s > 16) s = 16; // limit stack to 16 bytes in SHAREBANK
+
+       // provide addresses for sharebank
+       if (low) *low = l;
+       if (high) *high = l + s - 1;
+       if (size) *size = s;
+       //fprintf(stderr, "%s: low %x, high %x, size %x, shared 1\n", __FUNCTION__, l, h, s);
+       return 1;
+    }
+}
+
+PIC_device * pic14_getPIC(void)
+{
+    return pic;
+}