add if and else, and fix nested loops (hopefully)

This commit is contained in:
r4 2021-12-23 19:58:00 +01:00
parent ef63742015
commit 97e8e32ebc
6 changed files with 87 additions and 14 deletions

14
ir.c
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@ -49,11 +49,21 @@ void irtoks_app(IRToks *v, IRTok t) {
v->toks[v->len++] = t; v->toks[v->len++] = t;
} }
void irtoks_app_irtoks(IRToks *v, IRToks *other) { void irtoks_eat_irtoks(IRToks *v, IRToks *other, size_t jmp_offset) {
if (v->len+other->len > v->cap) if (v->len+other->len > v->cap)
v->toks = xrealloc(v->toks, sizeof(IRTok) * (other->len + (v->cap *= 2))); v->toks = xrealloc(v->toks, sizeof(IRTok) * (other->len + (v->cap *= 2)));
for (size_t i = 0; i < other->len; i++) for (size_t i = 0; i < other->len; i++) {
/* correct for changed jump addresses */
if (other->toks[i].instr == IRJmp)
other->toks[i].Jmp.iaddr += jmp_offset;
else if (other->toks[i].instr == IRJnz)
other->toks[i].CJmp.iaddr += jmp_offset;
v->toks[v->len++] = other->toks[i]; v->toks[v->len++] = other->toks[i];
}
/* We're not calling irtoks_term() because we don't want associated items
* (for example function arguments) to get deallocated as well. */
free(other->toks);
} }
static void print_val(const Value *v); static void print_val(const Value *v);

2
ir.h
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@ -87,7 +87,7 @@ void irtoks_init_long(IRToks *v);
void irtoks_init_short(IRToks *v); void irtoks_init_short(IRToks *v);
void irtoks_term(IRToks *v); void irtoks_term(IRToks *v);
void irtoks_app(IRToks *v, IRTok t); void irtoks_app(IRToks *v, IRTok t);
void irtoks_app_irtoks(IRToks *v, IRToks *other); void irtoks_eat_irtoks(IRToks *v, IRToks *other, size_t jmp_offset);
void print_ir(IRToks *v, const BuiltinFunc *builtin_funcs); void print_ir(IRToks *v, const BuiltinFunc *builtin_funcs);

2
lex.c
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@ -54,6 +54,8 @@ TokList lex(const char *s) {
} }
if (streq_0_n("if", start, i)) if (streq_0_n("if", start, i))
emit(&toks, &pos, (Tok){ .kind = TokIf }); emit(&toks, &pos, (Tok){ .kind = TokIf });
else if (streq_0_n("else", start, i))
emit(&toks, &pos, (Tok){ .kind = TokElse });
else if (streq_0_n("while", start, i)) else if (streq_0_n("while", start, i))
emit(&toks, &pos, (Tok){ .kind = TokWhile }); emit(&toks, &pos, (Tok){ .kind = TokWhile });
else { else {

81
parse.c
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@ -5,6 +5,8 @@
#include "map.h" #include "map.h"
#include "runtime.h" #include "runtime.h"
static BuiltinFunc *bf;
typedef struct Scope { typedef struct Scope {
struct Scope *parent; struct Scope *parent;
size_t mem_addr; size_t mem_addr;
@ -589,8 +591,17 @@ static void stmt(IRToks *out_ir, TokList *toks, Map *funcs, Scope *sc, TokListIt
IRParam cond; IRParam cond;
TRY_ELSE(cond = expr_into_irparam(&cond_ir, toks, funcs, sc, t->next), irtoks_term(&cond_ir)); TRY_ELSE(cond = expr_into_irparam(&cond_ir, toks, funcs, sc, t->next), irtoks_term(&cond_ir));
/* parse loop body */
TRY_ELSE(stmt(out_ir, toks, funcs, sc, t->next), irtoks_term(&cond_ir));
/* finally we know where the jmp from the beginning has to jump to */
out_ir->toks[jmp_instr_iaddr].Jmp.iaddr = out_ir->len;
/* append condition IR to program IR, then terminate condition IR stream */
irtoks_eat_irtoks(out_ir, &cond_ir, out_ir->len-1);
/* add conditional jump */ /* add conditional jump */
irtoks_app(&cond_ir, (IRTok){ irtoks_app(out_ir, (IRTok){
.ln = t->next->tok.ln, .ln = t->next->tok.ln,
.col = t->next->tok.col, .col = t->next->tok.col,
.instr = IRJnz, .instr = IRJnz,
@ -600,17 +611,63 @@ static void stmt(IRToks *out_ir, TokList *toks, Map *funcs, Scope *sc, TokListIt
}, },
}); });
/* parse loop body */
TRY_ELSE(stmt(out_ir, toks, funcs, sc, t->next), irtoks_term(&cond_ir));
/* finally we know where the jmp from the beginning has to jump to */
out_ir->toks[jmp_instr_iaddr].Jmp.iaddr = out_ir->len;
/* append condition IR to program IR, then terminate condition IR stream */
irtoks_app_irtoks(out_ir, &cond_ir);
irtoks_term(&cond_ir);
t = t->next; t = t->next;
} else if (t->tok.kind == TokIf) {
/* How if is generally implemented in IR:
* 0: some stuff evaluating condition xyz
* 1: jmp to 5 if condition xyz is met
* 2: some_code in else
* 4: jmp to 6
* 5: some_code in if
* */
/* parse condition */
IRParam cond;
TRY(cond = expr_into_irparam(out_ir, toks, funcs, sc, t->next));
/* add conditional jmp instruction */
size_t if_cjmp_instr_iaddr = out_ir->len;
irtoks_app(out_ir, (IRTok){
.ln = t->tok.ln,
.col = t->tok.col,
.instr = IRJnz,
.CJmp = {
.iaddr = 0, /* unknown for now */
.condition = cond,
},
});
/* parse if body */
IRToks if_body;
irtoks_init_short(&if_body);
TRY_ELSE(stmt(&if_body, toks, funcs, sc, t->next), irtoks_term(&if_body));
if (t->next->tok.kind == TokElse) {
toklist_del(toks, t->next, t->next);
/* parse and add else body */
TRY_ELSE(stmt(out_ir, toks, funcs, sc, t->next), irtoks_term(&if_body));
}
/* add jmp instruction to jump back to common code */
size_t else_jmp_instr_iaddr = out_ir->len;
irtoks_app(out_ir, (IRTok){
.ln = t->tok.ln,
.col = t->tok.col,
.instr = IRJmp,
.Jmp = {
.iaddr = 0, /* unknown for now */
},
});
/* set if condition jmp target */
out_ir->toks[if_cjmp_instr_iaddr].CJmp.iaddr = out_ir->len;
/* add if body */
irtoks_eat_irtoks(out_ir, &if_body, out_ir->len-1);
/* set else jmp target */
out_ir->toks[else_jmp_instr_iaddr].CJmp.iaddr = out_ir->len;
} else if (t->tok.kind == TokOp && t->tok.Op == OpNewLn) { } else if (t->tok.kind == TokOp && t->tok.Op == OpNewLn) {
} else { } else {
/* assume expression */ /* assume expression */
@ -621,6 +678,8 @@ static void stmt(IRToks *out_ir, TokList *toks, Map *funcs, Scope *sc, TokListIt
} }
IRToks parse(TokList *toks, BuiltinFunc *builtin_funcs, size_t n_builtin_funcs) { IRToks parse(TokList *toks, BuiltinFunc *builtin_funcs, size_t n_builtin_funcs) {
bf = builtin_funcs;
Map funcs; Map funcs;
map_init(&funcs, sizeof(BuiltinFunc)); map_init(&funcs, sizeof(BuiltinFunc));
for (size_t i = 0; i < n_builtin_funcs; i++) { for (size_t i = 0; i < n_builtin_funcs; i++) {

1
tok.c
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@ -35,6 +35,7 @@ const char *tok_str[TokKindEnumSize] = {
[TokAssign] = "=", [TokAssign] = "=",
[TokDeclare] = ":=", [TokDeclare] = ":=",
[TokIf] = "if", [TokIf] = "if",
[TokElse] = "else",
[TokWhile] = "while", [TokWhile] = "while",
}; };

1
tok.h
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@ -69,6 +69,7 @@ typedef struct Tok {
TokAssign, TokAssign,
TokDeclare, TokDeclare,
TokIf, TokIf,
TokElse,
TokWhile, TokWhile,
TokKindEnumSize, TokKindEnumSize,
} kind; } kind;