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Fix types, signatures, and arguments.

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This commit is contained in:
sBubshait 2024-06-12 00:49:25 +01:00
parent 17d31a74e3
commit 269a150926
4 changed files with 15 additions and 461 deletions
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11
src/assemble.c
View File

@ -14,19 +14,20 @@ int main(int argc, char **argv) {
}
// Load the source file into memory
char **source = readAssemblyFile(argv[1]);
int lineCount = countLines(argv[1]);
char **source = readAssemblyFile(argv[1], lineCount);
// Parse the source file
a64inst_instruction *instructions = parse(source);
a64inst_instruction *instructions = parse(source, lineCount);
// First Pass: Create the symbol table
st *table = firstPass(instructions, 1000); // 1000 is just a temp fix.
st *table = firstPass(instructions, lineCount);
// Second Pass: Assemble the instructions
word *binary = secondPass(instructions, 1000, table); // 1000 is just a temp fix.
word *binary = secondPass(instructions, lineCount, table); // 1000 is just a temp fix.
// Write the binary to the output file
writeBinaryFile(binary, argv[2], 1000); // 1000 is just a temp fix.
writeBinaryFile(binary, argv[2], lineCount); // 1000 is just a temp fix.
/* TODO: FREE MEMORY!! */

448
src/execute.c
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@ -1,448 +0,0 @@
#include <stdlib.h>
#include <assert.h>
#include "execute.h"
#include "print.h"
// Defines the maximum value that can be held in a register
#define MAX_REG_VAL ((1 << DWORD_BITS) - 1)
// The number of bits to shift the immediate value in an arithmetic immediate data processing
// instruction if the shift flag is enabled.
#define DPI_ARITHM_SHIFT 12
// The number of bits to shift the immediate value in a wide move immediate data processing
// instruction if the shift flag is enabled.
#define DPI_WIDEMOV_SHIFT 16
// Prototypes
void execute_SDT(Machine *state, a64inst_instruction *inst);
void execute_Branch(Machine *state, a64inst_instruction *inst);
void executeMultiply(Machine *state, a64inst_instruction *inst);
// Return maximum of two dwords
static dword max(dword a, dword b) {
return a > b ? a : b;
}
// Truncate a given value to the size of a word or dword depending on the register type
static dword truncateValue(dword value, a64inst_regType regType) {
if (regType == a64inst_X) {
return value;
} else {
return (word)value;
//return value & (dword)(((dword)1 << WORD_BITS) - 1);
}
}
// Sign extend a given value to a 64-bit signed integer given the number of bits
static int64_t signExtend(dword value, unsigned int n) {
if (n == 0 || n >= 64) {
// If n_bits is 0 or greater than or equal to 64, return the value as is
return (int64_t)value;
}
uint64_t sign_bit_mask = (uint64_t)1 << (n - 1);
// Mask to isolate the n-bit value
uint64_t n_bit_mask = (sign_bit_mask << 1) - 1;
// Check if the sign bit is set
if (value & sign_bit_mask) {
// Sign bit is set, extend the sign
return (int64_t)(value | ~n_bit_mask);
} else {
// Sign bit is not set, return the value as is
return (int64_t)(value & n_bit_mask);
}
}
// Read from processor register, ensuring that a valid register specifier is given
// and accounting for the case where the zero register is accessed. Truncate
// the 32 most significant bits stored in the R register when reading W register.
static dword readRegister(Machine *state, a64inst_regSpecifier reg, a64inst_regType regType) {
assert(reg <= REGISTER_COUNT);
if (reg == ZERO_REGISTER) {
return 0;
} else {
return truncateValue(state->registers[reg], regType);
}
}
// TODO:
// Write to a processor register, ensuring that a valid register specifier is given
// and truncating the value being written when it can't fit in the specified register
static void writeRegister(Machine *state, a64inst_regSpecifier reg, a64inst_regType regType, dword value) {
assert(reg <= REGISTER_COUNT);
if (reg != ZERO_REGISTER) {
state->registers[reg] = truncateValue(value, regType);
}
}
// Returns the position of the MSB of the given register type
inline static dword getMSBPos(a64inst_regType regType) {
return (regType ? DWORD_BITS : WORD_BITS) - 1;
}
// Returns the MSB of the given value assuming it's of the size stored in the given register type
inline static uint8_t getMSB(dword value, a64inst_regType regType) {
return value >> getMSBPos(regType);
}
// Updates N and Z condition codes given the machine and a result value
static void updateCondNZ(Machine *state, dword result, a64inst_regType regType) {
state->conditionCodes.Negative = getMSB(result, regType);
state->conditionCodes.Zero = result == 0;
}
// Execute a data processing immediate instruction
static void executeDPImmediate(Machine *state, a64inst_instruction *inst) {
assert(inst->type == a64inst_DPIMMEDIATE);
a64inst_regType regType = inst->data.DPImmediateData.regType;
a64inst_regSpecifier dest = inst->data.DPImmediateData.dest;
switch(inst->data.DPImmediateData.DPIOpType) {
// Execute an arithmetic immediate data processing instruction
case a64inst_DPI_ARITHM:;
// If shift flag is enabled, logical left shift by the number of bits specified by the architecture
dword arithmImm = inst->data.DPImmediateData.processOpData.arithmData.immediate;
dword srcVal = state->registers[inst->data.DPImmediateData.processOpData.arithmData.src];
if (inst->data.DPImmediateData.processOpData.arithmData.shiftImmediate) {
arithmImm = truncateValue(arithmImm << DPI_ARITHM_SHIFT, regType);
}
switch(inst->data.DPImmediateData.processOp) {
dword result;
case(a64inst_ADDS):
result = srcVal + arithmImm;
writeRegister(state, dest, regType, result);
updateCondNZ(state, result, regType);
state->conditionCodes.Overflow = max(srcVal, arithmImm) > result;
state->conditionCodes.Carry = state->conditionCodes.Overflow;
break;
case(a64inst_ADD):
writeRegister(state, dest, regType, srcVal + arithmImm);
break;
case(a64inst_SUBS):
result = srcVal - arithmImm;
writeRegister(state, dest, regType, result);
updateCondNZ(state, result, regType);
state->conditionCodes.Overflow = srcVal < result;
state->conditionCodes.Carry = state->conditionCodes.Overflow;
break;
case(a64inst_SUB):
writeRegister(state, dest, regType, srcVal - arithmImm);
break;
// Unknown opcode detected!
default:
fprintf(stderr, "Unknown opcode detected in a DPI arithmetic instruction!\n");
break;
}
break;
// Execute a wide move immediate data processing instruction
case a64inst_DPI_WIDEMOV:;
uint8_t shiftScalar = inst->data.DPImmediateData.processOpData.wideMovData.shiftScalar;
dword wideMovImm = inst->data.DPImmediateData.processOpData.wideMovData.immediate;
// NOTE: Not checking that shiftScalar has valid value for 32bit registers. Possibly add explicit error.
//printf("%x\n", wideMovImm << (shiftScalar * DPI_WIDEMOV_SHIFT) & );
wideMovImm = truncateValue(wideMovImm << (shiftScalar * DPI_WIDEMOV_SHIFT), regType);
switch(inst->data.DPImmediateData.processOp) {
case(a64inst_MOVN):
writeRegister(state, dest, regType, ~wideMovImm);
break;
case(a64inst_MOVZ):
writeRegister(state, dest, regType, wideMovImm);
break;
case(a64inst_MOVK):;
dword result = readRegister(state, dest, regType);
result = (result & ~(((1lu << DPI_WIDEMOV_SHIFT) - 1) << shiftScalar * DPI_WIDEMOV_SHIFT)) | wideMovImm;
writeRegister(state, dest, regType, result);
break;
default:
fprintf(stderr, "Unknown opcode detected in a DPI wide move instruction!\n");
break;
}
break;
// Unknown instruction detected!
default:
fprintf(stderr, "Attempting to execute instruction with unknown DPI operand type!\n");
break;
}
}
// Execute a data processing register instruction
static void executeDPRegister(Machine *state, a64inst_instruction *inst) {
assert(inst->type == a64inst_DPREGISTER);
a64inst_regType regType = inst->data.DPRegisterData.regType;
a64inst_regSpecifier dest = inst->data.DPRegisterData.dest;
dword src1Val = readRegister(state, inst->data.DPRegisterData.src1, regType);
dword src2Val = readRegister(state, inst->data.DPRegisterData.src2, regType);
switch(inst->data.DPRegisterData.DPROpType) {
// Execute an arithmetic or logic register data processing instruction
case a64inst_DPR_ARITHMLOGIC:;
// Apply shift to value held in second register
a64inst_DPRegister_ArithmLogicData *arithmLogicData = &inst->data.DPRegisterData.processOpData.arithmLogicData;
uint8_t shiftAmount = arithmLogicData->shiftAmount;
switch(arithmLogicData->shiftType) {
case a64inst_LSL:
src2Val = truncateValue(src2Val << shiftAmount, regType);
break;
case a64inst_LSR:
src2Val = truncateValue(src2Val >> shiftAmount, regType);
break;
case a64inst_ASR:
if (regType == a64inst_X) {
src2Val = truncateValue((int64_t)src2Val >> shiftAmount, regType);
} else {
src2Val = truncateValue((int32_t)src2Val >> shiftAmount, regType);
}
break;
case a64inst_ROR:
if (arithmLogicData->type != a64inst_DPR_LOGIC) {
fprintf(stderr, "Attempting to perform ROR shift on non-logic register data processing instruction!\n");
}
src2Val = truncateValue(src2Val >> shiftAmount | src2Val << (getMSBPos(regType) - shiftAmount), regType);
break;
default:
fprintf(stderr, "Attempting to execute arithmetic/logic register data processing instruction with invalid shift type!\n");
break;
}
// Negate second operand if negShiftedSrc2 flag is enabled
if (arithmLogicData->negShiftedSrc2) {
src2Val = truncateValue(~src2Val, regType);
}
dword result;
switch(arithmLogicData->type) {
case a64inst_DPR_ARITHM:
switch(inst->data.DPRegisterData.processOp) {
case(a64inst_ADDS):
result = src1Val + src2Val;
writeRegister(state, dest, regType, result);
updateCondNZ(state, result, regType);
state->conditionCodes.Overflow = max(src1Val, src2Val) > result;
state->conditionCodes.Carry = state->conditionCodes.Overflow;
break;
case(a64inst_ADD):
writeRegister(state, dest, regType, src1Val + src2Val);
break;
case(a64inst_SUBS):
result = src1Val - src2Val;
writeRegister(state, dest, regType, result);
updateCondNZ(state, result, regType);
state->conditionCodes.Overflow = getMSB(src1Val, regType) != getMSB(src2Val, regType) && getMSB(src1Val, regType) != getMSB(result, regType);
state->conditionCodes.Carry = src1Val >= src2Val;
break;
case(a64inst_SUB):
writeRegister(state, dest, regType, src1Val - src2Val);
break;
// Unknown opcode detected!
default:
fprintf(stderr, "Unknown opcode detected in a DPI arithmetic instruction!\n");
break;
}
break;
case a64inst_DPR_LOGIC:
switch(inst->data.DPRegisterData.processOp) {
case a64inst_AND:
writeRegister(state, dest, regType, src1Val & src2Val);
break;
case a64inst_OR:
writeRegister(state, dest, regType, src1Val | src2Val);
break;
case a64inst_XOR:
writeRegister(state, dest, regType, src1Val ^ src2Val);
break;
case a64inst_AND_FLAGGED:;
result = src1Val & src2Val;
writeRegister(state, dest, regType, result);
state->conditionCodes.Overflow = 0;
state->conditionCodes.Carry = 0;
updateCondNZ(state, result, regType);
break;
}
break;
default:
fprintf(stderr, "Attempting to execute an instruction with an unknown DPR arithmetic or logic subtype!\n");
break;
}
break;
// Execute a multiply register data processing instruction
case a64inst_DPR_MULTIPLY:
break;
// Unknown instruction detected!
default:
fprintf(stderr, "Attempting to execute instruction with unknown DPR operand type!\n");
break;
}
}
void execute(Machine *state, a64inst_instruction *inst) {
switch (inst->type) {
// Halt the program
case a64inst_HALT:
break;
// Execute a data processing immediate instruction
case a64inst_DPIMMEDIATE:
executeDPImmediate(state, inst);
break;
// Execute a branch instruction
case a64inst_BRANCH:
execute_Branch(state, inst);
break;
// Execute a data processing register instruction
case a64inst_DPREGISTER:
if (inst->data.DPRegisterData.DPROpType == a64inst_DPR_MULTIPLY)
executeMultiply(state, inst);
else
executeDPRegister(state, inst);
break;
case a64inst_SINGLETRANSFER:
execute_SDT(state, inst);
break;
// Unknown instruction
default:
break;
}
}
void execute_SDT(Machine *state, a64inst_instruction *inst) {
word address;
bool isLoad;
if (inst->data.SingleTransferData.SingleTransferOpType == a64inst_SINGLE_TRANSFER_LOAD_LITERAL) {
// Load Literal
isLoad = true;
address = state->pc + inst->data.SingleTransferData.processOpData.loadLiteralData.offset * 4;
} else {
address = state->registers[inst->data.SingleTransferData.processOpData.singleDataTransferData.base];
isLoad = inst->data.SingleTransferData.processOpData.singleDataTransferData.transferType == a64inst_LOAD;
switch (inst->data.SingleTransferData.processOpData.singleDataTransferData.addressingMode) {
case a64inst_UNSIGNED_OFFSET:
address += inst->data.SingleTransferData.processOpData.singleDataTransferData.a64inst_addressingModeData.unsignedOffset * (inst->data.SingleTransferData.regType == a64inst_W ? 4 : 8);
break;
case a64inst_REGISTER_OFFSET:
address += state->registers[inst->data.SingleTransferData.processOpData.singleDataTransferData.a64inst_addressingModeData.offsetReg];
break;
case a64inst_PRE_INDEXED:
address += inst->data.SingleTransferData.processOpData.singleDataTransferData.a64inst_addressingModeData.indexedOffset;
state->registers[inst->data.SingleTransferData.processOpData.singleDataTransferData.base] = address;
break;
case a64inst_POST_INDEXED:
state->registers[inst->data.SingleTransferData.processOpData.singleDataTransferData.base] = address + inst->data.SingleTransferData.processOpData.singleDataTransferData.a64inst_addressingModeData.indexedOffset;
break;
}
}
if (isLoad) {
if (inst->data.SingleTransferData.regType == a64inst_W) {
// 32 bit access
state->registers[inst->data.SingleTransferData.target] = readWord(state->memory, address);
} else {
state->registers[inst->data.SingleTransferData.target] = readDoubleWord(state->memory, address);
}
} else {
*(word *)(state->memory + address) = state->registers[inst->data.SingleTransferData.target];
// Update base register if post indexed
if (inst->data.SingleTransferData.processOpData.singleDataTransferData.addressingMode == a64inst_POST_INDEXED) {
writeRegister(state, inst->data.SingleTransferData.processOpData.singleDataTransferData.base, inst->data.SingleTransferData.regType == a64inst_W, address + inst->data.SingleTransferData.processOpData.singleDataTransferData.a64inst_addressingModeData.indexedOffset);
}
}
}
static bool isConditionMet(Machine* state, a64inst_ConditionType cond) {
switch(cond) {
case EQ:
return state->conditionCodes.Zero;
case NE:
return !state->conditionCodes.Zero;
case GE:
return state->conditionCodes.Negative == state->conditionCodes.Overflow;
case LT:
return state->conditionCodes.Negative != state->conditionCodes.Overflow;
case GT:
return !state->conditionCodes.Zero && (state->conditionCodes.Negative == state->conditionCodes.Overflow);
case LE:
return state->conditionCodes.Zero || (state->conditionCodes.Negative != state->conditionCodes.Overflow);
case AL:
return true;
default:
fprintf(stderr, "Unknown condition specified!\n");
exit(1);
}
}
void execute_Branch(Machine *state, a64inst_instruction *inst) {
switch (inst->data.BranchData.BranchType) {
case a64inst_UNCONDITIONAL:
state->pc += signExtend(inst->data.BranchData.processOpData.unconditionalData.unconditionalOffset * 4, 26);
break;
case a64inst_REGISTER:
state->pc = state->registers[inst->data.BranchData.processOpData.registerData.src];
break;
case a64inst_CONDITIONAL:
if (isConditionMet(state, inst->data.BranchData.processOpData.conditionalData.cond)) {
state->pc += signExtend(inst->data.BranchData.processOpData.conditionalData.offset * 4, 19);
}
break;
}
}
void executeMultiply(Machine *state, a64inst_instruction *inst) {
dword product = state->registers[inst->data.DPRegisterData.src1] * state->registers[inst->data.DPRegisterData.src2];
dword sum = readRegister(state, inst->data.DPRegisterData.processOpData.multiplydata.summand, inst->data.DPRegisterData.regType) + (inst->data.DPRegisterData.processOpData.multiplydata.negProd ? -product : product);
writeRegister(state, inst->data.DPRegisterData.dest, inst->data.DPRegisterData.regType, sum);
}

15
src/parser.c
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@ -1,3 +1,4 @@
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
@ -172,8 +173,9 @@ void classifyOpcode(char* opcode, a64inst_instruction *instr, char *operandList[
}
void tokeniseOperands(char* str, int *operandCount, char *operands[], int *numOperands){
char *operandsDupe = NULL;
operandsDupe = strcpy(operandsDupe, str);
assert(str != NULL);
char operandsDupe[strlen(str)+1];
strcpy(operandsDupe, str);
char *operand = strtok(operandsDupe, OPERAND_DELIMITER);
operands[0] = operand;
@ -200,8 +202,8 @@ void parser_instruction(char asmLine[], a64inst_instruction *instr) {
//"opcode operand1, {operand2}, ..."
//duplicated as strtok modifies the input string
char *stringptr = NULL;
stringptr = strcpy(stringptr, asmLine);
char stringptr[strlen(asmLine) + 1];
strcpy(stringptr, asmLine);
char *opcode = strtok(stringptr, " ");
char *operands = strtok(NULL, "");
@ -254,9 +256,8 @@ void parser_instruction(char asmLine[], a64inst_instruction *instr) {
// Takes an array of strings, each string representing an assembly instruction.
// Returns an array of a64inst_instruction pointers, each representing an instruction.
// Note. The array of strings must be NULL-terminated????
a64inst_instruction *parse(char **asmLines) {
a64inst_instruction *instructions = malloc(sizeof(a64inst_instruction) * 1000);
a64inst_instruction *parse(char **asmLines, int lineCount) {
a64inst_instruction *instructions = malloc(sizeof(a64inst_instruction) * lineCount);
int i = 0;
while (asmLines[i] != NULL) {

2
src/parser.h
View File

@ -3,4 +3,4 @@
#define OPERAND_DELIMITER ", "
#define HALT_ASM_CMD "and x0, x0, x0"
a64inst_instruction *parse(char **asmLines);
a64inst_instruction *parse(char **asmLines, int lineCount);