doylet/PerformanceAwareProgramming
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Prepare for part 3

Browse Source
This commit is contained in:
doylet
2024-03-03 22:33:57 +11:00
parent d01cf53ff8
commit 8083a7c782
20 changed files with 3283 additions and 131 deletions
Download Patch File Download Diff File Expand all files Collapse all files
part1/sim8086.c
+12 -22
View File
@@ -382,8 +382,7 @@ S86_Opcode S86_DecodeOpcode(S86_BufferIterator *buffer_it,
size_t op_code_size = 0;
op_code_bytes[op_code_size++] = S86_BufferIteratorNextByte(buffer_it);
// NOTE: Match the assembly bytes to the desired instruction
// =====================================================================
// NOTE: Match the assembly bytes to the desired instruction ///////////////////////////////////
S86_OpDecodeType op_decode_type = S86_OpDecodeType_Count;
S86_OpDecode const *op_decode = NULL;
for (size_t op_index = 0;
@@ -392,13 +391,11 @@ S86_Opcode S86_DecodeOpcode(S86_BufferIterator *buffer_it,
{
S86_OpDecode const *item = decode_table + op_index;
// NOTE: Check first instruction byte
// =================================================================
// NOTE: Check first instruction byte //////////////////////////////////////////////////////
if ((op_code_bytes[0] & item->op_mask0) != item->op_bits0)
continue;
// NOTE Check multi-byte instruction
// =================================================================
// NOTE Check multi-byte instruction ///////////////////////////////////////////////////////
// If the matched instruction has a bit mask for the 2nd byte, this
// is a multi-byte instruction. Check if the 2nd byte checks out.
bool op_match = true;
@@ -418,8 +415,7 @@ S86_Opcode S86_DecodeOpcode(S86_BufferIterator *buffer_it,
}
}
// NOTE: Disassemble bytes to assembly mnemonics
// =================================================================
// NOTE: Disassemble bytes to assembly mnemonics ///////////////////////////////////////////////
S86_ASSERT(op_code_size > 0 && op_code_size <= S86_ARRAY_UCOUNT(op_code_bytes));
S86_ASSERT(op_decode_type != S86_OpDecodeType_Count && "Unknown instruction");
@@ -677,8 +673,7 @@ S86_Opcode S86_DecodeOpcode(S86_BufferIterator *buffer_it,
case S86_OpDecodeType_ORImmediateToAccum: /*FALLTHRU*/
case S86_OpDecodeType_XORImmediateToAccum: /*FALLTHRU*/
case S86_OpDecodeType_MOVImmediateToReg: {
// NOTE: Parse opcode control bits
// =============================================================
// NOTE: Parse opcode control bits /////////////////////////////////////////////////////
S86_ASSERT(op_code_size == 1);
uint8_t w = 0;
if (op_decode_type == S86_OpDecodeType_ADDImmediateToAccum ||
@@ -695,16 +690,14 @@ S86_Opcode S86_DecodeOpcode(S86_BufferIterator *buffer_it,
w = (op_code_bytes[0] & 0b0000'1000) >> 3;
}
// NOTE: Parse data payload
// =============================================================
// NOTE: Parse data payload ////////////////////////////////////////////////////////////
uint16_t data = S86_BufferIteratorNextByte(buffer_it);
if (w) { // 16 bit data
uint8_t data_hi = S86_BufferIteratorNextByte(buffer_it);
data |= (uint16_t)(data_hi) << 8;
}
// NOTE: Disassemble
// =============================================================
// NOTE: Disassemble ///////////////////////////////////////////////////////////////////
result.effective_addr = S86_EffectiveAddress_Dest;
result.src = S86_MnemonicOp_Immediate;
result.wide = w;
@@ -893,8 +886,7 @@ char const CLI_ARG_DUMP[] = "--dump";
int main(int argc, char **argv)
{
// NOTE: Argument handling
// =========================================================================
// NOTE: Argument handling /////////////////////////////////////////////////////////////////////
if (argc < 2) {
PRINT_USAGE;
return -1;
@@ -965,8 +957,7 @@ int main(int argc, char **argv)
return -1;
}
// NOTE: Sim8086
// =========================================================================
// NOTE: Sim8086 ///////////////////////////////////////////////////////////////////////////////
S86_OpDecode const DECODE_TABLE[] = {
[S86_OpDecodeType_MOVRegOrMemToOrFromReg] = {.op_mask0 = 0b1111'1100, .op_mask1 = 0b0000'0000,
.op_bits0 = 0b1000'1000, .op_bits1 = 0b0000'0000, .mnemonic = S86_Mnemonic_MOV},
@@ -1257,8 +1248,7 @@ int main(int argc, char **argv)
.op_bits0 = 0b0010'0110, .op_bits1 = 0b0000'0000, .mnemonic = S86_Mnemonic_SEGMENT},
};
// NOTE: Decode assembly
// =========================================================================
// NOTE: Decode assembly ///////////////////////////////////////////////////////////////////////
if (exec_mode) {
if (log_cycle_counts != CycleCount_None) { // NOTE: Print disclaimer + header
S86_PrintLn(S86_STR8("**************"));
@@ -1337,7 +1327,7 @@ int main(int argc, char **argv)
continue;
}
// NOTE: Simulate instruction ==============================================================
// NOTE: Simulate instruction //////////////////////////////////////////////////////////////
bool cycle_count_8088 = log_cycle_counts == CycleCount_8088;
uint32_t base_clocks = 0;
uint32_t effective_address_clocks = 0;
@@ -1800,7 +1790,7 @@ int main(int argc, char **argv)
clocks_counter += base_clocks + effective_address_clocks + transfer_penalty_clocks;
// NOTE: Printing ==========================================================================
// NOTE: Printing //////////////////////////////////////////////////////////////////////////
S86_PrintFmt(" ; ");
// NOTE: Clocks
part1/sim8086.h
+1 -2
View File
@@ -1,5 +1,4 @@
// NOTE: Sim8086
// ============================================================================
// NOTE: Sim8086 ///////////////////////////////////////////////////////////////////////////////////
typedef enum S86_OpDecodeType {
S86_OpDecodeType_MOVRegOrMemToOrFromReg,
S86_OpDecodeType_MOVImmediateToRegOrMem,