diff options
| -rw-r--r-- | instruction.c | 240 | ||||
| -rw-r--r-- | instruction.h | 42 | ||||
| -rw-r--r-- | load.c | 67 | ||||
| -rw-r--r-- | load.h | 10 | ||||
| -rwxr-xr-x | makefile | 5 | ||||
| -rwxr-xr-x | qdme.c | 303 | ||||
| -rwxr-xr-x | qdme.h | 40 |
7 files changed, 372 insertions, 335 deletions
diff --git a/instruction.c b/instruction.c new file mode 100644 index 0000000..a5fe208 --- /dev/null +++ b/instruction.c @@ -0,0 +1,240 @@ +#include "qdme.h" +#include "instruction.h" +#include <string.h> +#include <stdio.h> +#include <stdlib.h> + +/* InstFetch: Fetch the next instruction from memory into the given + * instruction */ +void InstFetch(inst_t *inst) { + uint32_t value = 0; + memcpy(&value, memory + pc, WORD_SIZE); + switch ((value & 0xFC000000) >> 26) { + case 0: + inst->type = RTYPE; + inst->r.op = (value & 0xFC000000) >> 26; + inst->r.rs = (value & 0x03E00000) >> 21; + inst->r.rt = (value & 0x001F0000) >> 16; + inst->r.rd = (value & 0x0000F800) >> 11; + inst->r.shamt = (value & 0x000007C0) >> 6; + inst->r.func = value & 0x0000002F; + break; + case 2: + case 3: + inst->type = JTYPE; + inst->j.op = (value & 0xFC000000) >> 26; + inst->j.addr = value & 0X03FFFFFF; + break; + default: + inst->type = ITYPE; + inst->i.op = (value & 0xFC000000) >> 26; + inst->i.rs = (value & 0x03E00000) >> 21; + inst->i.rt = (value & 0x001F0000) >> 16; + inst->i.imm = value & 0x0000FFFF; + break; + } + if (inst->value == 0) { + inst->type = NOP; + } + pc += WORD_SIZE; +} + +static void Syscall(void) { + char c, *s; + switch (regFile[V0]) { + case 1: // print integer + printf("%d", regFile[A0]); + break; + case 2: // print float + break; + case 3: // print double + break; + case 4: // print string + printf("%s", memory + regFile[A0]); + break; + case 5: // read integer + scanf("%d", (int *)regFile + V0); + break; + case 6: // read float + break; + case 7: // read double + break; + case 8: // read string + s = (char *)calloc(regFile[A0], sizeof(char)); + fgets(s, regFile[A0], stdin); + memcpy(memory + regFile[A1], s, regFile[A0]); + free(s); + break; + case 9: // sbrk + break; + case 10: //exit + exitStatus = 0; + run = false; + break; + case 11: // print char + printf("%c", regFile[A0]); + break; + case 12: // read char + c = 0; + scanf("%c", &c); + regFile[V0] = c; + break; + case 13: // open file + break; + case 14: // read from file + break; + case 15: // write to file + break; + case 16: // close file + break; + case 17: // exit2 + exitStatus = regFile[A0]; + run = false; + break; + } +} + +/* ExecRtype: Execute a given R-Type instruction */ +static void ExecRtype(const inst_t inst) { + rtype_t r = inst.r; + uint32_t a = regFile[r.rs], b = regFile[r.rt]; + uint64_t mult = 0; + switch (r.func) { + case 32: // add + regFile[r.rd] = (signed)a + (signed)b; + break; + case 33: // addu + regFile[r.rd] = a + b; + break; + case 36: // and + regFile[r.rd] = a & b; + break; + case 37: // or + regFile[r.rd] = a | b; + break; + case 42: // slt + regFile[r.rd] = (signed)a < (signed)b; + break; + case 43: // sltu + regFile[r.rd] = a < b; + break; + case 34: // sub + regFile[r.rd] = (signed)a - (signed)b; + break; + case 35: // subu + regFile[r.rd] = a - b; + break; + case 38: // xor + regFile[r.rd] = a ^ b; + break; + case 0: // sll + regFile[r.rd] = b << r.shamt; + break; + case 3: // sra + regFile[r.rd] = (signed)b >> r.shamt; + break; + case 2: // srl + regFile[r.rd] = b >> r.shamt; + break; + case 26: // div + hi = (signed)a % (signed)b; + lo = (signed)a / (signed)b; + break; + case 27: // divu + hi = a % b; + lo = a / b; + break; + case 24: // mult + mult = (signed)a * (signed)b; + hi = (0xFFFFFFFF00000000 & mult) >> 32; + lo = 0x00000000FFFFFFFF & mult; + break; + case 25: // multu + mult = a * b; + hi = (0xFFFFFFFF00000000 & mult) >> 32; + lo = 0x00000000FFFFFFFF & mult; + break; + case 16: // MFHI + regFile[r.rd] = hi; + break; + case 18: // MFLO + regFile[r.rd] = lo; + break; + case 17: // MTHI + hi = regFile[r.rs]; + break; + case 19: // MTLO + lo = regFile[r.rs]; + break; + case 9: // jalr + regFile[r.rd] = pc; + /* Intentional Fall Through */ + case 8: // jr + pc = a; + break; + case 12: // syscall + Syscall(); + break; + } +} + +/* InstExec: Execute a given instruction */ +void InstExec(const inst_t inst) { + if (inst.type == NOP) { + return; + } + int16_t imm = inst.i.imm; + int32_t a = regFile[inst.i.rs]; + switch (inst.j.op) { + case 0: // R-type instruction + ExecRtype(inst); + break; + case 3: // jal + regFile[RA] = pc; + /* intentional fall through */ + case 2: // j + pc = (0xF0000000 & pc ) | (signed)inst.j.addr; + break; + case 4: // beq + pc = (regFile[inst.i.rs] == regFile[inst.i.rt]) ? pc + 4 + + imm : pc; + break; + case 5: // bne + pc = (regFile[inst.i.rs] != regFile[inst.i.rt]) ? pc + 4 + + imm : pc; + break; + case 8: // addi + regFile[inst.i.rt] = a + imm; + break; + case 9: // addiu + regFile[inst.i.rt] = (unsigned)a + imm; + break; + case 12: // andi + regFile[inst.i.rt] = a & imm; + break; + case 13: // ori + regFile[inst.i.rt] = a | imm; + break; + case 14: // xori + regFile[inst.i.rt] = a ^ imm; + break; + case 10: // slti + regFile[inst.i.rt] = a < imm; + break; + case 11: // sltiu + regFile[inst.i.rt] = (unsigned)a < (uint16_t)imm; + break; + case 15: // lui + regFile[inst.i.rt] = imm << 16; + break; + case 35: // lw + memcpy(regFile + inst.i.rt, memory + regFile[inst.i.rs] + imm, + WORD_SIZE); + break; + case 43: // sw + memcpy(memory + regFile[inst.i.rs] + imm, regFile + inst.i.rt, + WORD_SIZE); + break; + } +} + diff --git a/instruction.h b/instruction.h new file mode 100644 index 0000000..2e10ed6 --- /dev/null +++ b/instruction.h @@ -0,0 +1,42 @@ +#ifndef INSTRUCTION_H +#define INSTRUCTION_H + +#include <stdint.h> + +typedef struct { + unsigned int op: 6; + unsigned int rs: 5; + unsigned int rt: 5; + unsigned int rd: 5; + unsigned int shamt: 5; + unsigned int func: 6; +} rtype_t; + +typedef struct { + unsigned int op: 6; + unsigned int rs: 5; + unsigned int rt: 5; + unsigned int imm: 16; +} itype_t; + +typedef struct { + unsigned int op: 6; + unsigned int addr: 26; +} jtype_t; + +typedef enum { NOP, RTYPE, ITYPE, JTYPE } type_t; + +typedef struct { + type_t type; + union { + rtype_t r; + jtype_t j; + itype_t i; + uint32_t value; + }; +} inst_t; + +void InstFetch(inst_t *inst); +void InstExec(const inst_t inst); + +#endif @@ -0,0 +1,67 @@ +#include "load.h" +#include "qdme.h" +#include "elf.h" +#include <stdlib.h> + +int LoadBinary(const char * const path) { + FILE *fp = fopen(path, "r"); + if (fp == NULL) { + perror("LoadBinary"); + return -1; + } + + ElfHeader_t e = ReadElf(fp); + if (!ValidateElf(e)) { + return -1; + } + + pc = e.e_entry; + + const size_t n = e.e_phnum; + ProgramHeader_t *p = (ProgramHeader_t *)calloc(n, e.e_phentsize); + if (p == NULL) { + perror("calloc"); + return -1; + } + ReadProgramHeader(n, p, fp); + + for (size_t i = 0; i < n; i++) { + memsize += p[i].memsz; + } + + if ((memory = (uint8_t *)calloc(memsize, sizeof(uint8_t))) == NULL) { + perror("calloc"); + free((void *)p); + fclose(fp); + return -1; + } + + for (size_t i = 0; i < n; i++) { + if (LoadProgramHeader(p[i], fp) == -1) { + free((void *)p); + fclose(fp); + return -1; + } + } + + free((void *)p); + fclose(fp); + return 0; +} + +/* LoadProgramHeader: Load the program segment described by the given program + * header from file fp. Returns 0 on success and -1 on failure. */ +int LoadProgramHeader(ProgramHeader_t p, FILE *fp) { + uint8_t *memloc = memory + p.vaddr; + size_t s = p.filesz; + if (fseek(fp, p.offset, SEEK_SET) != 0) { + perror("fseek"); + return -1; + } + fread(memloc, sizeof(uint8_t), s, fp); + if (ferror(fp)) { + return -1; + } + return 0; +} + @@ -0,0 +1,10 @@ +#ifndef LOAD_H +#define LOAD_H + +#include "elf.h" +#include <stdio.h> + +int LoadBinary(const char * const path); +int LoadProgramHeader(ProgramHeader_t p, FILE *fp); + +#endif @@ -1,7 +1,7 @@ CC=gcc CFLAGS=-Wall -Werror -pedantic --std=c17 -OBJS=qdme.o elf.o -SRCS=qdme.c elf.c +OBJS=qdme.o elf.o instruction.o load.o +SRCS=qdme.c elf.c instruction.c load.c TARGET=qdme %.o: %.c %.h @@ -17,3 +17,4 @@ qdme: $(OBJS) clean: rm -rf $(TARGET) $(OBJS) + @@ -1,10 +1,9 @@ #include <stdio.h> #include <stdlib.h> -#include <stdbool.h> #include <string.h> -#include <arpa/inet.h> #include "qdme.h" -#include "elf.h" +#include "load.h" +#include "instruction.h" uint8_t *memory = NULL; size_t memsize = MEM_PADD; @@ -13,242 +12,6 @@ uint32_t regFile[32] = {0}; int exitStatus = 0; bool run = true; -int LoadProgramHeader(ProgramHeader_t p, FILE *fp); - -/* InstFetch: Fetch the next instruction from memory into the given - * instruction */ -void InstFetch(inst_t *inst) { - uint32_t value = 0; - memcpy(&value, memory + pc, WORD_SIZE); - switch ((value & 0xFC000000) >> 26) { - case 0: - inst->type = RTYPE; - inst->r.op = (value & 0xFC000000) >> 26; - inst->r.rs = (value & 0x03E00000) >> 21; - inst->r.rt = (value & 0x001F0000) >> 16; - inst->r.rd = (value & 0x0000F800) >> 11; - inst->r.shamt = (value & 0x000007C0) >> 6; - inst->r.func = value & 0x0000002F; - break; - case 2: - case 3: - inst->type = JTYPE; - inst->j.op = (value & 0xFC000000) >> 26; - inst->j.addr = value & 0X03FFFFFF; - break; - default: - inst->type = ITYPE; - inst->i.op = (value & 0xFC000000) >> 26; - inst->i.rs = (value & 0x03E00000) >> 21; - inst->i.rt = (value & 0x001F0000) >> 16; - inst->i.imm = value & 0x0000FFFF; - break; - } - if (inst->value == 0) { - inst->type = NOP; - } - pc += WORD_SIZE; -} - -void Syscall(void) { - char c, *s; - switch (regFile[V0]) { - case 1: // print integer - printf("%d", regFile[A0]); - break; - case 2: // print float - break; - case 3: // print double - break; - case 4: // print string - printf("%s", memory + regFile[A0]); - break; - case 5: // read integer - scanf("%d", (int *)regFile + V0); - break; - case 6: // read float - break; - case 7: // read double - break; - case 8: // read string - s = (char *)calloc(regFile[A0], sizeof(char)); - fgets(s, regFile[A0], stdin); - memcpy(memory + regFile[A1], s, regFile[A0]); - free(s); - break; - case 9: // sbrk - break; - case 10: //exit - exitStatus = 0; - run = false; - break; - case 11: // print char - printf("%c", regFile[A0]); - break; - case 12: // read char - c = 0; - scanf("%c", &c); - regFile[V0] = c; - break; - case 13: // open file - break; - case 14: // read from file - break; - case 15: // write to file - break; - case 16: // close file - break; - case 17: // exit2 - exitStatus = regFile[A0]; - run = false; - break; - } -} - -/* ExecRtype: Execute a given R-Type instruction */ -void ExecRtype(const inst_t inst) { - rtype_t r = inst.r; - uint32_t a = regFile[r.rs], b = regFile[r.rt]; - uint64_t mult = 0; - switch (r.func) { - case 32: // add - regFile[r.rd] = (signed)a + (signed)b; - break; - case 33: // addu - regFile[r.rd] = a + b; - break; - case 36: // and - regFile[r.rd] = a & b; - break; - case 37: // or - regFile[r.rd] = a | b; - break; - case 42: // slt - regFile[r.rd] = (signed)a < (signed)b; - break; - case 43: // sltu - regFile[r.rd] = a < b; - break; - case 34: // sub - regFile[r.rd] = (signed)a - (signed)b; - break; - case 35: // subu - regFile[r.rd] = a - b; - break; - case 38: // xor - regFile[r.rd] = a ^ b; - break; - case 0: // sll - regFile[r.rd] = b << r.shamt; - break; - case 3: // sra - regFile[r.rd] = (signed)b >> r.shamt; - break; - case 2: // srl - regFile[r.rd] = b >> r.shamt; - break; - case 26: // div - hi = (signed)a % (signed)b; - lo = (signed)a / (signed)b; - break; - case 27: // divu - hi = a % b; - lo = a / b; - break; - case 24: // mult - mult = (signed)a * (signed)b; - hi = (0xFFFFFFFF00000000 & mult) >> 32; - lo = 0x00000000FFFFFFFF & mult; - break; - case 25: // multu - mult = a * b; - hi = (0xFFFFFFFF00000000 & mult) >> 32; - lo = 0x00000000FFFFFFFF & mult; - break; - case 16: // MFHI - regFile[r.rd] = hi; - break; - case 18: // MFLO - regFile[r.rd] = lo; - break; - case 17: // MTHI - hi = regFile[r.rs]; - break; - case 19: // MTLO - lo = regFile[r.rs]; - break; - case 9: // jalr - regFile[r.rd] = pc; - /* Intentional Fall Through */ - case 8: // jr - pc = a; - break; - case 12: // syscall - Syscall(); - break; - } -} - -/* InstExec: Execute a given instruction */ -void InstExec(const inst_t inst) { - if (inst.type == NOP) { - return; - } - int16_t imm = inst.i.imm; - int32_t a = regFile[inst.i.rs]; - switch (inst.j.op) { - case 0: // R-type instruction - ExecRtype(inst); - break; - case 3: // jal - regFile[RA] = pc; - /* intentional fall through */ - case 2: // j - pc = (0xF0000000 & pc ) | (signed)inst.j.addr; - break; - case 4: // beq - pc = (regFile[inst.i.rs] == regFile[inst.i.rt]) ? pc + 4 + - imm : pc; - break; - case 5: // bne - pc = (regFile[inst.i.rs] != regFile[inst.i.rt]) ? pc + 4 + - imm : pc; - break; - case 8: // addi - regFile[inst.i.rt] = a + imm; - break; - case 9: // addiu - regFile[inst.i.rt] = (unsigned)a + imm; - break; - case 12: // andi - regFile[inst.i.rt] = a & imm; - break; - case 13: // ori - regFile[inst.i.rt] = a | imm; - break; - case 14: // xori - regFile[inst.i.rt] = a ^ imm; - break; - case 10: // slti - regFile[inst.i.rt] = a < imm; - break; - case 11: // sltiu - regFile[inst.i.rt] = (unsigned)a < (uint16_t)imm; - break; - case 15: // lui - regFile[inst.i.rt] = imm << 16; - break; - case 35: // lw - memcpy(regFile + inst.i.rt, memory + regFile[inst.i.rs] + imm, - WORD_SIZE); - break; - case 43: // sw - memcpy(memory + regFile[inst.i.rs] + imm, regFile + inst.i.rt, - WORD_SIZE); - break; - } -} - void CycleCpu(void) { inst_t instFetch, instExec; memset(&instFetch, 0, sizeof(inst_t)); @@ -260,68 +23,6 @@ void CycleCpu(void) { } } -int LoadBinary(const char * const path) { - FILE *fp = fopen(path, "r"); - if (fp == NULL) { - perror("LoadBinary"); - return -1; - } - - ElfHeader_t e = ReadElf(fp); - if (!ValidateElf(e)) { - return -1; - } - - pc = e.e_entry; - - const size_t n = e.e_phnum; - ProgramHeader_t *p = (ProgramHeader_t *)calloc(n, e.e_phentsize); - if (p == NULL) { - perror("calloc"); - return -1; - } - ReadProgramHeader(n, p, fp); - - for (size_t i = 0; i < n; i++) { - memsize += p[i].memsz; - } - - if ((memory = (uint8_t *)calloc(memsize, sizeof(uint8_t))) == NULL) { - perror("calloc"); - free((void *)p); - fclose(fp); - return -1; - } - - for (size_t i = 0; i < n; i++) { - if (LoadProgramHeader(p[i], fp) == -1) { - free((void *)p); - fclose(fp); - return -1; - } - } - - free((void *)p); - fclose(fp); - return 0; -} - -/* LoadProgramHeader: Load the program segment described by the given program - * header from file fp. Returns 0 on success and -1 on failure. */ -int LoadProgramHeader(ProgramHeader_t p, FILE *fp) { - uint8_t *memloc = memory + p.vaddr; - size_t s = p.filesz; - if (fseek(fp, p.offset, SEEK_SET) != 0) { - perror("fseek"); - return -1; - } - fread(memloc, sizeof(uint8_t), s, fp); - if (ferror(fp)) { - return -1; - } - return 0; -} - int main(int argc, char *argv[]) { if (LoadBinary(*++argv) == -1) { return -1; @@ -1,7 +1,9 @@ #ifndef _QDME_H #define _QDME_H +#include <stdbool.h> #include <stdint.h> +#include <stddef.h> #define MEM_PADD 12 #define RA 31 @@ -13,38 +15,12 @@ #define A3 7 #define WORD_SIZE 4 -typedef struct { - unsigned int op: 6; - unsigned int rs: 5; - unsigned int rt: 5; - unsigned int rd: 5; - unsigned int shamt: 5; - unsigned int func: 6; -} rtype_t; - -typedef struct { - unsigned int op: 6; - unsigned int rs: 5; - unsigned int rt: 5; - unsigned int imm: 16; -} itype_t; - -typedef struct { - unsigned int op: 6; - unsigned int addr: 26; -} jtype_t; - -typedef enum { NOP, RTYPE, ITYPE, JTYPE } type_t; - -typedef struct { - type_t type; - union { - rtype_t r; - jtype_t j; - itype_t i; - uint32_t value; - }; -} inst_t; +extern uint8_t *memory; +extern size_t memsize; +extern uint32_t pc, hi, lo; +extern uint32_t regFile[32]; +extern int exitStatus; +extern bool run; #endif |