Skip to content

Commit

Permalink
operators
Browse files Browse the repository at this point in the history
  • Loading branch information
pedrommaiaa committed Jun 18, 2021
1 parent 218e674 commit 3a11914
Show file tree
Hide file tree
Showing 15 changed files with 474 additions and 96 deletions.
Binary file modified flow
View file
Binary file not shown.
31 changes: 21 additions & 10 deletions grammar.txt
View file
Original file line number Diff line number Diff line change
Expand Up @@ -14,10 +14,10 @@ additive_expression:
| additive_expression '-' multiplicative_expression
;

multiplicative_expression:
number
| number '*' multiplicative_expression
| number '/' multiplicative_expression
multiplicative_expression: prefix_expression
| multiplicative_expression '*' prefix_expression
| multiplicative_expression '/' prefix_expression
| multiplicative_expression '%' prefix_expression
;

number: INTLIT_T
Expand Down Expand Up @@ -99,17 +99,28 @@ function_call : identifier '(' expression ')'
return_statement: 'return' '(' expression ')'
;

prefix_expression: primary
| '*' prefix_expression
| '%' prefix_expression
prefix_expression: postfix_expression
| '++' prefix_expression
| '--' prefix_expression
| prefix_operator prefix_expression
;

primary_expression: IDENTIFIER
| CONSTANT
| STRING_LITERAL
primary_expression: T_IDENT
| T_INTLIT
| T_STRLIT
| '(' expression ')'
;

postfix_expression : primary_expression
| postfix_expression '[' expression ']'
| postfix_expression '(' expression ')'
| postfix_expression '++'
| postfix_expression '--'
;

prefix_operator: '&'
| '*'
| '-'
| '~'
| '!'
;
126 changes: 110 additions & 16 deletions src/cg.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -76,34 +76,59 @@ int cgloadint(int value, int type) {
}

// Load a value from a variable into a register.
// Return the number of the register
int cgloadglob(int id) {
// Return the number of the register. If the
// operation is pre- or post-increment/decrement,
// also perform this action.
int cgloadglob(int id, int op) {
// Get a new register
int r = alloc_register();

// Print out the code to initialise it
switch (Gsym[id].type) {
case P_CHAR:
if (op == A_PREINC)
fprintf(Outfile, "\tincb\t%s(\%%rip)\n", Gsym[id].name);
if (op == A_PREDEC)
fprintf(Outfile, "\tdecb\t%s(\%%rip)\n", Gsym[id].name);
fprintf(Outfile, "\tmovzbq\t%s(%%rip), %s\n", Gsym[id].name,
reglist[r]);
if (op == A_POSTINC)
fprintf(Outfile, "\tincb\t%s(\%%rip)\n", Gsym[id].name);
if (op == A_POSTDEC)
fprintf(Outfile, "\tdecb\t%s(\%%rip)\n", Gsym[id].name);
break;
case P_INT:
fprintf(Outfile, "\tmovzbl\t%s(\%%rip), %s\n", Gsym[id].name,
if (op == A_PREINC)
fprintf(Outfile, "\tincl\t%s(\%%rip)\n", Gsym[id].name);
if (op == A_PREDEC)
fprintf(Outfile, "\tdecl\t%s(\%%rip)\n", Gsym[id].name);
fprintf(Outfile, "\tmovslq\t%s(\%%rip), %s\n", Gsym[id].name,
reglist[r]);
if (op == A_POSTINC)
fprintf(Outfile, "\tincl\t%s(\%%rip)\n", Gsym[id].name);
if (op == A_POSTDEC)
fprintf(Outfile, "\tdecl\t%s(\%%rip)\n", Gsym[id].name);
break;
case P_LONG:
case P_CHARPTR:
case P_INTPTR:
case P_LONGPTR:
if (op == A_PREINC)
fprintf(Outfile, "\tincq\t%s(\%%rip)\n", Gsym[id].name);
if (op == A_PREDEC)
fprintf(Outfile, "\tdecq\t%s(\%%rip)\n", Gsym[id].name);
fprintf(Outfile, "\tmovq\t%s(\%%rip), %s\n", Gsym[id].name, reglist[r]);
if (op == A_POSTINC)
fprintf(Outfile, "\tincq\t%s(\%%rip)\n", Gsym[id].name);
if (op == A_POSTDEC)
fprintf(Outfile, "\tdecq\t%s(\%%rip)\n", Gsym[id].name);
break;
default:
fatald("Bad type in cgloadglob:", Gsym[id].type);
}
return (r);
}


// Given the label number of a global string,
// load its address into a new register
int cgloadglobstr(int id) {
Expand All @@ -113,7 +138,6 @@ int cgloadglobstr(int id) {
return (r);
}


// Add two registers together and return
// the number of the register with the result
int cgadd(int r1, int r2) {
Expand Down Expand Up @@ -149,6 +173,71 @@ int cgdiv(int r1, int r2) {
return (r1);
}

int cgand(int r1, int r2) {
fprintf(Outfile, "\tandq\t%s, %s\n", reglist[r1], reglist[r2]);
free_register(r1);
return (r2);
}

int cgor(int r1, int r2) {
fprintf(Outfile, "\torq\t%s, %s\n", reglist[r1], reglist[r2]);
free_register(r1);
return (r2);
}

int cgxor(int r1, int r2) {
fprintf(Outfile, "\txorq\t%s, %s\n", reglist[r1], reglist[r2]);
free_register(r1);
return (r2);
}

int cgshl(int r1, int r2) {
fprintf(Outfile, "\tmovb\t%s, %%cl\n", breglist[r2]);
fprintf(Outfile, "\tshlq\t%%cl, %s\n", reglist[r1]);
free_register(r2);
return (r1);
}

int cgshr(int r1, int r2) {
fprintf(Outfile, "\tmovb\t%s, %%cl\n", breglist[r2]);
fprintf(Outfile, "\tshrq\t%%cl, %s\n", reglist[r1]);
free_register(r2);
return (r1);
}

// Negate a register's value
int cgnegate(int r) {
fprintf(Outfile, "\tnegq\t%s\n", reglist[r]);
return (r);
}

// Invert a register's value
int cginvert(int r) {
fprintf(Outfile, "\tnotq\t%s\n", reglist[r]);
return (r);
}

// Logically negate a register's value
int cglognot(int r) {
fprintf(Outfile, "\ttest\t%s, %s\n", reglist[r], reglist[r]);
fprintf(Outfile, "\tsete\t%s\n", breglist[r]);
fprintf(Outfile, "\tmovzbq\t%s, %s\n", breglist[r], reglist[r]);
return (r);
}

// Convert an integer value to a boolean value. Jump if
// it's an IF or WHILE operation
int cgboolean(int r, int op, int label) {
fprintf(Outfile, "\ttest\t%s, %s\n", reglist[r], reglist[r]);
if (op == A_IF || op == A_WHILE)
fprintf(Outfile, "\tje\tL%d\n", label);
else {
fprintf(Outfile, "\tsetnz\t%s\n", breglist[r]);
fprintf(Outfile, "\tmovzbq\t%s, %s\n", breglist[r], reglist[r]);
}
return (r);
}

// Call a function with one argument from the given register
// Return the register with the result
int cgcall(int r, int id) {
Expand All @@ -164,7 +253,7 @@ int cgcall(int r, int id) {
// Shift a register left by a constant
int cgshlconst(int r, int val) {
fprintf(Outfile, "\tsalq\t$%d, %s\n", val, reglist[r]);
return(r);
return (r);
}

// Store a register's value into a variable
Expand Down Expand Up @@ -214,28 +303,33 @@ void cgglobsym(int id) {
fprintf(Outfile, "%s:", Gsym[id].name);

// Generate the space
for (int i=0; i < Gsym[id].size; i++) {
switch(typesize) {
case 1: fprintf(Outfile, "\t.byte\t0\n"); break;
case 4: fprintf(Outfile, "\t.long\t0\n"); break;
case 8: fprintf(Outfile, "\t.quad\t0\n"); break;
default: fatald("Unknown typesize in cgglobsym: ", typesize);
for (int i = 0; i < Gsym[id].size; i++) {
switch (typesize) {
case 1:
fprintf(Outfile, "\t.byte\t0\n");
break;
case 4:
fprintf(Outfile, "\t.long\t0\n");
break;
case 8:
fprintf(Outfile, "\t.quad\t0\n");
break;
default:
fatald("Unknown typesize in cgglobsym: ", typesize);
}
}
}


// Generate a global string and its start label
void cgglobstr(int l, char *strvalue) {
char *cptr;
cglabel(l);
for (cptr= strvalue; *cptr; cptr++) {
for (cptr = strvalue; *cptr; cptr++) {
fprintf(Outfile, "\t.byte\t%d\n", *cptr);
}
fprintf(Outfile, "\t.byte\t0\n");
}


// List of comparison instructions,
// in AST order: A_EQ, A_NE, A_LT, A_GT, A_LE, A_GE
static char *cmplist[] =
Expand Down Expand Up @@ -327,7 +421,7 @@ int cgderef(int r, int type) {
fprintf(Outfile, "\tmovzbq\t(%s), %s\n", reglist[r], reglist[r]);
break;
case P_INTPTR:
fprintf(Outfile, "\tmovq\t(%s), %s\n", reglist[r], reglist[r]);
fprintf(Outfile, "\tmovslq\t(%s), %s\n", reglist[r], reglist[r]);
break;
case P_LONGPTR:
fprintf(Outfile, "\tmovq\t(%s), %s\n", reglist[r], reglist[r]);
Expand Down
Loading

0 comments on commit 3a11914

Please sign in to comment.