Merge pull request #2 from maximumspatium/master

Various CPU emulation fixes + new command-line debugger.

CMakeLists.txt

@@ -21,6 +21,7 @@ set(SOURCE_FILES
         viacuda.cpp
         main.cpp
         davbus.cpp
+        debugger.cpp
         )
  
 set(HEADER_FILES
@@ -33,7 +34,8 @@ set(HEADER_FILES
         ppcmemory.h
         viacuda.h
         davbus.h
+        debugger.h
         )
  
 add_executable(dingusppc ${SOURCE_FILES} ${HEADER_FILES})
-install (TARGETS dingusppc DESTINATION bin)
+install (TARGETS dingusppc DESTINATION bin)

debugger.cpp

@@ -0,0 +1,111 @@
+#include <stdio.h>
+#include <string>
+#include <sstream>
+#include <iostream>
+#include <map>
+#include "ppcemumain.h"
+#include "ppcmemory.h"
+
+
+using namespace std;
+
+void show_help()
+{
+    cout << "Debugger commands:" << endl;
+    cout << "  step      -- execute single instruction" << endl;
+    cout << "  until X   -- execute until address X is reached" << endl;
+    cout << "  regs      -- dump content of the GRPs" << endl;
+    cout << "  disas X,n -- disassemble N instructions starting at address X" << endl;
+    cout << "  quit      -- quit the debugger" << endl << endl;
+    cout << "Pressing ENTER will repeat last command." << endl;
+}
+
+void dump_regs()
+{
+    for (uint32_t i = 0; i < 32; i++)
+        cout << "GPR " << dec << i << " : " << hex << ppc_state.ppc_gpr[i] << endl;
+
+    cout << "PC: "  << hex << ppc_state.ppc_pc     << endl;
+    cout << "LR: "  << hex << ppc_state.ppc_spr[8] << endl;
+    cout << "CR: "  << hex << ppc_state.ppc_cr     << endl;
+    cout << "CTR: " << hex << ppc_state.ppc_spr[9] << endl;
+    cout << "XER: " << hex << ppc_state.ppc_spr[1] << endl;
+    cout << "MSR: " << hex << ppc_state.ppc_msr    << endl;
+}
+
+void execute_single_instr()
+{
+    quickinstruction_translate(ppc_state.ppc_pc);
+    //cout << "Current instruction: " << hex << ppc_cur_instruction << endl;
+    ppc_main_opcode();
+    if (grab_branch && !grab_exception) {
+        //cout << "Grab branch, EA: " << hex << ppc_next_instruction_address << endl;
+        ppc_state.ppc_pc = ppc_next_instruction_address;
+        grab_branch = 0;
+        ppc_tbr_update();
+    }
+    else if (grab_return || grab_exception) {
+        ppc_state.ppc_pc = ppc_next_instruction_address;
+        grab_exception = 0;
+        grab_return = 0;
+        ppc_tbr_update();
+    }
+    else {
+        ppc_state.ppc_pc += 4;
+        ppc_tbr_update();
+    }
+    ppc_cur_instruction = 0;
+}
+
+void execute_until(uint32_t goal_addr)
+{
+    while(ppc_state.ppc_pc != goal_addr)
+        execute_single_instr();
+}
+
+void enter_debugger()
+{
+    string inp, cmd, addr_str, last_cmd;
+    uint32_t addr;
+    std::stringstream ss;
+
+    cout << "Welcome to the PowerPC debugger." << endl;
+    cout << "Please enter a command or 'help'." << endl << endl;
+
+    while (1) {
+        cout << "ppcdbg> ";
+
+        /* reset string stream */
+        ss.str("");
+        ss.clear();
+
+        cmd = "";
+        getline(cin, inp, '\n');
+        ss.str(inp);
+        ss >> cmd;
+
+        if (cmd.empty() && !last_cmd.empty()) {
+            cmd = last_cmd;
+            cout << cmd << endl;
+        }
+        if (cmd == "help") {
+            show_help();
+        } else if (cmd == "quit") {
+            break;
+        } else if (cmd == "regs") {
+            dump_regs();
+        } else if (cmd == "step") {
+            execute_single_instr();
+        } else if (cmd == "until") {
+            ss >> addr_str;
+            addr = stol(addr_str, NULL, 16);
+            execute_until(addr);
+        } else if (cmd == "disas") {
+            cout << "Disassembling not implemented yet. Sorry!" << endl;
+        } else {
+            cout << "Unknown command: " << cmd << endl;
+            continue;
+        }
+        last_cmd = cmd;
+    }
+}

debugger.h

@@ -0,0 +1,6 @@
+#ifndef DEBUGGER_H_
+#define DEBUGGER_H_
+
+void enter_debugger(void);
+
+#endif // DEBUGGER_H_

main.cpp

@@ -25,6 +25,7 @@
 #include "viacuda.h"
 #include "mpc106.h"
 #include "openpic.h"
+#include "debugger.h"
 //#include <vector>
 
 #define max_16b_int 65535
@@ -729,7 +730,7 @@ int main(int argc, char **argv)
             uint32_t grab_bp = 0x0;
 
             std::cout << hex << "Enter the address in hex for where to stop execution." << endl;
-            cin >> hex >> opcode_entered;
+            cin >> hex >> grab_bp;
 
             execute_interpreter_bp(grab_bp);
         }
@@ -757,7 +758,7 @@ int main(int argc, char **argv)
                 quickinstruction_translate(ppc_state.ppc_pc);
                 ppc_main_opcode();
                 if (grab_branch & !grab_exception){
-                    ppc_state.ppc_pc = ppc_effective_address;
+                    ppc_state.ppc_pc = ppc_next_instruction_address;
                     grab_branch = 0;
                     ppc_tbr_update();
                 }
@@ -846,6 +847,8 @@ int main(int argc, char **argv)
                     ppc_cur_instruction = 0;
                 }
             }
+        } else if (checker == "debugger") {
+            enter_debugger();
         }
     }
     else{

makefile

@@ -1,6 +1,6 @@
-OBJS	= main.o macioserial.o macscsi.o macswim3.o mpc106.o openpic.o poweropcodes.o ppcfpopcodes.o ppcgekkoopcodes.o ppcmemory.o ppcopcodes.o viacuda.o davbus.o
-SOURCE	= main.cpp macioserial.cpp macscsi.cpp macswim3.cpp mpc106.cpp openpic.cpp poweropcodes.cpp ppcfpopcodes.cpp ppcgekkoopcodes.cpp ppcmemory.cpp ppcopcodes.cpp viacuda.cpp davbus.cpp
-HEADER	= macioserial.h macscsi.h macswim3.h mpc106.h openpic.h ppcemumain.h ppcmemory.h viacuda.h
+OBJS	= main.o macioserial.o macscsi.o macswim3.o mpc106.o openpic.o poweropcodes.o ppcfpopcodes.o ppcgekkoopcodes.o ppcmemory.o ppcopcodes.o viacuda.o davbus.o debugger.o
+SOURCE	= main.cpp macioserial.cpp macscsi.cpp macswim3.cpp mpc106.cpp openpic.cpp poweropcodes.cpp ppcfpopcodes.cpp ppcgekkoopcodes.cpp ppcmemory.cpp ppcopcodes.cpp viacuda.cpp davbus.cpp debugger.cpp
+HEADER	= macioserial.h macscsi.h macswim3.h mpc106.h openpic.h ppcemumain.h ppcmemory.h viacuda.h debugger.h
 OUT	    = dingusppc
 CC	    = g++
 FLAGS	= -g -c -Wall -std=c++11
@@ -46,7 +46,10 @@ viacuda.o: viacuda.cpp
 	$(CC) $(FLAGS) viacuda.cpp 
 
 davbus.o: davbus.cpp
-	$(CC) $(FLAGS) davbus.cpp 
+	$(CC) $(FLAGS) davbus.cpp
+
+debugger.o: debugger.cpp
+	$(CC) $(FLAGS) debugger.cpp
 
 clean:
 	rm -f $(OBJS) $(OUT)

ppcmemory.cpp

@@ -163,7 +163,7 @@ void get_pointer_pteg1(uint32_t address_grab){
             grab_pteg1_ptr = machine_sysconfig_mem;
         }
         else{
-            printf("Uncharted territory: %x", address_grab);
+            printf("Uncharted territory: %x \n", address_grab);
         }
     }
     else if (address_grab < 0x80800000){
@@ -240,7 +240,7 @@ void get_pointer_pteg2(uint32_t address_grab){
             grab_pteg2_ptr = machine_sysconfig_mem;
         }
         else{
-            printf("Uncharted territory: %x", address_grab);
+            printf("Uncharted territory: %x \n", address_grab);
         }
     }
     else if (address_grab < 0x80800000){
@@ -959,7 +959,7 @@ void quickinstruction_translate(uint32_t address_grab){
         else{
             storage_area = address_grab % 0x04000000;
             grab_macmem_ptr = machine_sysram_mem;
-            printf("Uncharted territory: %x", address_grab);
+            printf("Uncharted territory: %x \n", address_grab);
         }
     }
     else if (address_grab < 0x80800000){

ppcopcodes.cpp

@@ -168,7 +168,7 @@ void ppc_changecrf0(uint32_t set_result){
 
 //Affects the XER register's Carry Bit
 void ppc_carry(uint32_t a, uint32_t b){
-    if (b > ~a){
+    if (b < a){ // TODO: ensure it works everywhere
         ppc_state.ppc_spr[1] |= 0x20000000;
     }
     else{
@@ -384,9 +384,9 @@ void ppc_addcodot(){
 
 void ppc_adde(){
     ppc_grab_regsdab();
-    uint32_t grab_xer = ppc_state.ppc_spr[1] & 0x20000000;
-    ppc_result_d = ppc_result_a + ppc_result_b + grab_xer;
-    if (((grab_xer != 0) && (grab_xer > (~(ppc_result_b + ppc_result_a)))) || (ppc_result_d > ~ppc_result_a)){
+    uint32_t xer_ca = !!(ppc_state.ppc_spr[1] & 0x20000000);
+    ppc_result_d = ppc_result_a + ppc_result_b + xer_ca;
+    if ((ppc_result_d < ppc_result_a) || (xer_ca && (ppc_result_d == ppc_result_a))){
         ppc_state.ppc_spr[1] |= 0x20000000;
     }
     else{
@@ -646,7 +646,7 @@ void ppc_subfic(){
     ppc_grab_regsdasimm();
     not_this = ~ppc_result_a;
     ppc_result_d = not_this + simm + 1;
-    if (ppc_result_d < (not_this + 1)){
+    if (ppc_result_d <= not_this) {
         ppc_state.ppc_spr[1] |= 0x20000000;
     }
     else{
@@ -1272,7 +1272,7 @@ void ppc_rlwimi(){
     rot_sh = (ppc_cur_instruction >> 11) & 31;
     rot_mb = (ppc_cur_instruction >> 6) & 31;
     rot_me = (ppc_cur_instruction >> 1) & 31;
-    uint32_t step1 = (0xFFFFFFFF >> (rot_me + 1)) ^ (0xFFFFFFFF >> rot_mb);
+    uint32_t step1 = (0xFFFFFFFFUL << (31 - rot_me)) & (0xFFFFFFFFUL >> rot_mb);
     uint32_t step2 = (rot_me < rot_mb)? ~step1 : step1;
     uint32_t step3 = ((ppc_result_d << rot_sh) | (ppc_result_d >> (32-rot_sh)));
     ppc_result_a = (ppc_result_a & ~step2) | (step3 & step2);
@@ -1287,7 +1287,7 @@ void ppc_rlwinm(){
     rot_sh = (ppc_cur_instruction >> 11) & 31;
     rot_mb = (ppc_cur_instruction >> 6) & 31;
     rot_me = (ppc_cur_instruction >> 1) & 31;
-    uint32_t step1 = (0xFFFFFFFF >> (rot_me + 1)) ^ (0xFFFFFFFF >> rot_mb);
+    uint32_t step1 = (0xFFFFFFFFUL << (31 - rot_me)) & (0xFFFFFFFFUL >> rot_mb);
     uint32_t step2 = (rot_me < rot_mb)? ~step1 : step1;
     uint32_t step3 = ((ppc_result_d << rot_sh) | (ppc_result_d >> (32-rot_sh)));
     ppc_result_a = step2 & step3;
@@ -1301,7 +1301,7 @@ void ppc_rlwnm(){
     ppc_grab_regssab();
     rot_mb = (ppc_cur_instruction >> 6) & 31;
     rot_me = (ppc_cur_instruction >> 1) & 31;
-    uint32_t step1 = (0xFFFFFFFF >> (rot_me + 1)) ^ (0xFFFFFFFF >> rot_mb);
+    uint32_t step1 = (0xFFFFFFFFUL << (31 - rot_me)) & (0xFFFFFFFFUL >> rot_mb);
     uint32_t step2 = (rot_me < rot_mb)? ~step1 : step1;
     uint32_t step3 = ((ppc_result_d << ppc_result_b) | (ppc_result_d >> (32-ppc_result_b)));
     ppc_result_a = step2 & step3;
@@ -1355,7 +1355,6 @@ void ppc_mfmsr(){
     if ((ppc_state.ppc_msr & 0x4000) == 0){
         reg_d = (ppc_cur_instruction >> 21) & 31;
         ppc_state.ppc_gpr[reg_d] = ppc_state.ppc_msr;
-        ppc_store_result_regd();
     }
 }