Added logging of GPU/DSP states on exit.

[virtualjaguar] / src / gpu.cpp

diff --git a/src/gpu.cpp b/src/gpu.cpp
index d5e9054c13716717ce47cce6b86be120920fb268..9ee426425e42c69f3624939930258765cfde8a92 100644 (file)
--- a/src/gpu.cpp
+++ b/src/gpu.cpp
@@ -319,9 +319,10 @@ static uint32_t gpu_pointer_to_matrix;
 static uint32_t gpu_data_organization;
 static uint32_t gpu_control;
 static uint32_t gpu_div_control;
-// There is a distinct advantage to having these separated out--there's no need to clear
-// a bit before writing a result. I.e., if the result of an operation leaves a zero in
-// the carry flag, you don't have to zero gpu_flag_c before you can write that zero!
+// There is a distinct advantage to having these separated out--there's no need
+// to clear a bit before writing a result. I.e., if the result of an operation
+// leaves a zero in the carry flag, you don't have to zero gpu_flag_c before
+// you can write that zero!
 static uint8_t gpu_flag_z, gpu_flag_n, gpu_flag_c;
 uint32_t gpu_reg_bank_0[32];
 uint32_t gpu_reg_bank_1[32];
@@ -1050,11 +1051,13 @@ void GPUReset(void)
                *((uint32_t *)(&gpu_ram_8[i])) = rand();
 }
 
+
 uint32_t GPUReadPC(void)
 {
        return gpu_pc;
 }
 
+
 void GPUResetStats(void)
 {
        for(uint32_t i=0; i<64; i++)
@@ -1062,6 +1065,7 @@ void GPUResetStats(void)
        WriteLog("--> GPU stats were reset!\n");
 }
 
+
 void GPUDumpDisassembly(void)
 {
        char buffer[512];
@@ -1076,6 +1080,7 @@ void GPUDumpDisassembly(void)
        }
 }
 
+
 void GPUDumpRegisters(void)
 {
        WriteLog("\n---[GPU flags: NCZ %d%d%d]-----------------------\n", gpu_flag_n, gpu_flag_c, gpu_flag_z);
@@ -1099,6 +1104,7 @@ void GPUDumpRegisters(void)
        }
 }
 
+
 void GPUDumpMemory(void)
 {
        WriteLog("\n---[GPU data at 00F03000]---------------------------\n");
@@ -1107,8 +1113,23 @@ void GPUDumpMemory(void)
                        gpu_ram_8[i+1], gpu_ram_8[i+2], gpu_ram_8[i+3]);
 }
 
+
 void GPUDone(void)
 {
+       WriteLog("\n\n---------------------------------------------------------------------\n");
+       WriteLog("GPU I/O Registers\n");
+       WriteLog("---------------------------------------------------------------------\n");
+       WriteLog("F0%04X   (G_FLAGS): $%06X\n", 0x2100, (gpu_flags & 0xFFFFFFF8) | (gpu_flag_n << 2) | (gpu_flag_c << 1) | gpu_flag_z);
+       WriteLog("F0%04X    (G_MTXC): $%04X\n", 0x2104, gpu_matrix_control);
+       WriteLog("F0%04X    (G_MTXA): $%04X\n", 0x2108, gpu_pointer_to_matrix);
+       WriteLog("F0%04X     (G_END): $%02X\n", 0x210C, gpu_data_organization);
+       WriteLog("F0%04X      (G_PC): $%06X\n", 0x2110, gpu_pc);
+       WriteLog("F0%04X    (G_CTRL): $%06X\n", 0x2114, gpu_control);
+       WriteLog("F0%04X  (G_HIDATA): $%08X\n", 0x2118, gpu_hidata);
+       WriteLog("F0%04X  (G_REMAIN): $%08X\n", 0x211C, gpu_remain);
+       WriteLog("F0%04X (G_DIVCTRL): $%02X\n", 0x211C, gpu_div_control);
+       WriteLog("---------------------------------------------------------------------\n\n\n");
+
        WriteLog("GPU: Stopped at PC=%08X (GPU %s running)\n", (unsigned int)gpu_pc, GPU_RUNNING ? "was" : "wasn't");
 
        // Get the interrupt latch & enable bits
@@ -1125,12 +1146,9 @@ void GPUDone(void)
                        WriteLog("\t%17s %lu\n", gpu_opcode_str[i], gpu_opcode_use[i]);
        }
        WriteLog("\n");
-
-//     memory_free(gpu_ram_8);
-//     memory_free(gpu_reg_bank_0);
-//     memory_free(gpu_reg_bank_1);
 }
 
+
 //
 // Main GPU execution core
 //
@@ -2390,13 +2408,7 @@ static void gpu_opcode_div(void) // RN / RM
        if (doGPUDis)
                WriteLog("%06X: DIV    R%02u, R%02u (%s) [NCZ:%u%u%u, R%02u=%08X, R%02u=%08X] -> ", gpu_pc-2, IMM_1, IMM_2, (gpu_div_control & 0x01 ? "16.16" : "32"), gpu_flag_n, gpu_flag_c, gpu_flag_z, IMM_1, RM, IMM_2, RN);
 #endif
-// NOTE: remainder is NOT calculated correctly here!
-//       The original tried to get it right by checking to see if the
-//       remainder was negative, but that's too late...
-// The code there should do it now, but I'm not 100% sure...
-// [Now it should be correct, but not displaying correct behavior of the actual
-//  hardware. A step in the right direction.]
-
+#if 0
        if (RM)
        {
                if (gpu_div_control & 0x01)             // 16.16 division
@@ -2411,16 +2423,35 @@ static void gpu_opcode_div(void)        // RN / RM
                        gpu_remain = RN % RM;
                        RN = RN / RM;
                }
-
-// What we really should do here is figure out why this condition
-// happens in the real divide unit and emulate *that* behavior.
-#if 0
-               if ((gpu_remain - RM) & 0x80000000)     // If the result would have been negative...
-                       gpu_remain -= RM;                       // Then make it negative!
-#endif
        }
        else
+       {
+               // This is what happens according to SCPCD. NYAN!
                RN = 0xFFFFFFFF;
+               gpu_remain = 0;
+       }
+#else
+       // Real algorithm, courtesy of SCPCD: NYAN!
+       uint32_t q = RN;
+       uint32_t r = 0;
+
+       // If 16.16 division, stuff top 16 bits of RN into remainder and put the
+       // bottom 16 of RN in top 16 of quotient
+       if (gpu_div_control & 0x01)
+               q <<= 16, r = RN >> 16;
+
+       for(int i=0; i<32; i++)
+       {
+//             uint32_t sign = (r >> 31) & 0x01;
+               uint32_t sign = r & 0x80000000;
+               r = (r << 1) | ((q >> 31) & 0x01);
+               r += (sign ? RM : -RM);
+               q = (q << 1) | (((~r) >> 31) & 0x01);
+       }
+
+       RN = q;
+       gpu_remain = r;
+#endif
 
 #ifdef GPU_DIS_DIV
        if (doGPUDis)