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(uxnasm) Combine byte literals

This commit is contained in:
neauoire 2021-11-27 13:55:33 -08:00
parent 6ff202a23c
commit 4b6efa6fc6
1 changed files with 26 additions and 7 deletions
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33
src/uxnasm.c
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@ -47,6 +47,7 @@ typedef struct {
} Program;
Program p;
static int litlast = 0;
/* clang-format off */
@ -184,6 +185,7 @@ writebyte(Uint8 b, int lit)
if(lit) writebyte(findopcode("LIT"), 0);
p.data[p.ptr++] = b;
p.length = p.ptr;
litlast = 0;
}
static void
@ -194,6 +196,22 @@ writeshort(Uint16 s, int lit)
writebyte(s & 0xff, 0);
}
static void
writelitbyte(Uint8 b)
{
if(litlast) { /* combine literals */
Uint8 hb = p.data[p.ptr - 1];
p.ptr -= 2;
writeshort((hb << 8) + b, 1);
litlast = 0;
return;
}
p.data[p.ptr++] = findopcode("LIT");
p.data[p.ptr++] = b;
p.length = p.ptr;
litlast = 1;
}
static char *
sublabel(char *src, char *scope, char *name)
{
@ -216,11 +234,9 @@ prefill(char *scope, char *label, Uint16 addr)
static int
tokenize(char *w, FILE *f)
{
char word[64];
char subw[64];
char c;
Macro *m;
int i = 0;
char word[64], subw[64], c;
Macro *m;
if(slen(w) >= 63)
return error("Invalid token", w);
switch(w[0]) {
@ -259,14 +275,17 @@ tokenize(char *w, FILE *f)
if(!sihx(w + 1) || (slen(w) != 3 && slen(w) != 5))
return error("Invalid hex literal", w);
if(slen(w) == 3)
writebyte(shex(w + 1), 1);
writelitbyte(shex(w + 1));
else if(slen(w) == 5)
writeshort(shex(w + 1), 1);
break;
case '.': /* literal byte zero-page */
prefill(p.scope, w, p.ptr - litlast);
writelitbyte(0xff);
break;
case ',': /* literal byte relative */
prefill(p.scope, w, p.ptr);
writebyte(0xff, 1);
prefill(p.scope, w, p.ptr - litlast);
writelitbyte(0xff);
break;
case ';': /* literal short absolute */
prefill(p.scope, w, p.ptr);