From ab08e1c1b474faf78fae154d90f917ee0f9280ea Mon Sep 17 00:00:00 2001
From: Stefan Rueger <stefan.rueger@urclocks.com>
Date: Thu, 18 Jul 2024 23:39:25 +0100
Subject: [PATCH] Wrap round flash on disasm

---
 src/disasm.c         | 28 ++++++++++++++++++++--------
 src/disasm_private.h |  1 +
 src/disasm_tagfile.c |  8 ++++----
 3 files changed, 25 insertions(+), 12 deletions(-)

diff --git a/src/disasm.c b/src/disasm.c
index 48c108a1..d621dda8 100644
--- a/src/disasm.c
+++ b/src/disasm.c
@@ -139,6 +139,19 @@ static int Get_Next_Opcode(const char *Bitstream) {
   return -1;
 }
 
+int disasm_wrap(int addr) {
+  int flashsz = cx->dis_opts.FlashSize;
+
+  if(flashsz > 0) {
+    while(addr >= flashsz)
+      addr -= flashsz;
+    while(addr < 0)
+      addr += flashsz;
+  }
+
+  return addr;
+}
+
 int disasm(const char *Bitstream, int Read, int addr) {
   int Pos;
   int Opcode;
@@ -154,7 +167,7 @@ int disasm(const char *Bitstream, int Read, int addr) {
       if(Opcode == -1) {
         Pos += 2;
       } else {
-        cx->dis_op[Opcode].Callback(Bitstream + Pos, Pos + addr, cx->dis_op[Opcode].mnemo);
+        cx->dis_op[Opcode].Callback(Bitstream + Pos, disasm_wrap(Pos + addr), cx->dis_op[Opcode].mnemo);
         Pos += Get_Bitmask_Length(cx->dis_op[Opcode].Opcode_String) / 8;
       }
     }
@@ -182,14 +195,13 @@ int disasm(const char *Bitstream, int Read, int addr) {
       cx->dis_code[0] = 0;
       cx->dis_comment[0] = 0;
       cx->dis_after_code[0] = 0;
-      cx->dis_op[Opcode].Callback(Bitstream + Pos, Pos + addr, cx->dis_op[Opcode].mnemo);
+      cx->dis_op[Opcode].Callback(Bitstream + Pos, disasm_wrap(Pos + addr), cx->dis_op[Opcode].mnemo);
 
-      if(cx->dis_opts.Process_Labels) {
-        Print_JumpCalls(Pos + addr);
-      }
+      if(cx->dis_opts.Process_Labels)
+        Print_JumpCalls(disasm_wrap(Pos + addr));
 
       if(cx->dis_opts.Show_Addresses)
-        term_out("%4x:   ", Pos + addr);
+        term_out("%4x:   ", disasm_wrap(Pos + addr));
       if(cx->dis_opts.Show_Cycles)
         term_out("[%-3s] ", avr_opcodes[cx->dis_op[Opcode].mnemo].clock[cx->dis_opts.cycle_index]);
 
@@ -221,8 +233,8 @@ int disasm(const char *Bitstream, int Read, int addr) {
 
       Pos += Get_Bitmask_Length(cx->dis_op[Opcode].Opcode_String) / 8;
     } else {
-      term_out(".word 0x%02x%02x    ; Invalid opcode at 0x%04x\n", // @@@ show unoffical opcode what it might do
-        ((unsigned char *) Bitstream)[Pos + 1], ((unsigned char *) Bitstream)[Pos], Pos + addr);
+      term_out(".word 0x%02x%02x    ; Invalid opcode at 0x%04x\n",
+        ((unsigned char *) Bitstream)[Pos + 1], ((unsigned char *) Bitstream)[Pos], disasm_wrap(Pos + addr));
       Pos += 2;
     }
   }
diff --git a/src/disasm_private.h b/src/disasm_private.h
index 04bd3293..017d2eff 100644
--- a/src/disasm_private.h
+++ b/src/disasm_private.h
@@ -42,6 +42,7 @@
 #define TYPE_STRING     4
 
 void disasm_init_regfile(const AVRPART *p);
+int disasm_wrap(int addr);
 int Tagfile_FindLabelAddress(int Address);
 char *Tagfile_GetLabel(int TagIndex);
 char *Tagfile_GetLabelComment(int TagIndex);
diff --git a/src/disasm_tagfile.c b/src/disasm_tagfile.c
index b73965cc..5e53d37e 100644
--- a/src/disasm_tagfile.c
+++ b/src/disasm_tagfile.c
@@ -397,7 +397,7 @@ int Tagfile_Process_Data(const char *Bitstream, int Position, int offset) {
   int (*ProcessingFunction)(const char *, int, int, int, const char *) = NULL;
   char Buffer[32];
 
-  Index = Tagfile_FindPGMAddress(Position + offset);
+  Index = Tagfile_FindPGMAddress(disasm_wrap(Position + offset));
   if(Index == -1)
     return 0;
 
@@ -433,7 +433,7 @@ int Tagfile_Process_Data(const char *Bitstream, int Position, int offset) {
   }
   if(cx->dis_PGMLabels[Index].Count != 1)
     term_out("s");
-  term_out(" starting at 0x%x", Position + offset);
+  term_out(" starting at 0x%x", disasm_wrap(Position + offset));
 
   if(cx->dis_PGMLabels[Index].Comment != NULL) {
     term_out(" (%s)", cx->dis_PGMLabels[Index].Comment);
@@ -442,10 +442,10 @@ int Tagfile_Process_Data(const char *Bitstream, int Position, int offset) {
 
   if((cx->dis_PGMLabels[Index].Type == TYPE_ASTRING) || (cx->dis_PGMLabels[Index].Type == TYPE_STRING)) {
     if(cx->dis_PGMLabels[Index].Comment != NULL) {
-      snprintf(Buffer, sizeof(Buffer), "%x_%s", Position + offset, cx->dis_PGMLabels[Index].Comment);
+      snprintf(Buffer, sizeof(Buffer), "%x_%s", disasm_wrap(Position + offset), cx->dis_PGMLabels[Index].Comment);
       Sanitize_String(Buffer);
     } else {
-      snprintf(Buffer, sizeof(Buffer), "%x", Position + offset);
+      snprintf(Buffer, sizeof(Buffer), "%x", disasm_wrap(Position + offset));
     }
   }