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Let RGBASM write JR offsets in floating sections

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This requires some special-casing for `jr @` because the `jr` opcode has
already been emitted, but not the operand, so PC points to the middle.
Moved the RGBLINK test to RGBASM's folder, and created a new RGBLINK test.
This commit is contained in:
ISSOtm
2020-07-27 18:11:42 +02:00
parent b1adbcc77c
commit 762474d3ac
13 changed files with 47 additions and 25 deletions
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27
src/asm/rpn.c
View File

@@ -297,25 +297,28 @@ static int32_t shift(int32_t shiftee, int32_t amount)
}
}
static struct Symbol const *symbolOf(struct Expression const *expr)
struct Symbol const *rpn_SymbolOf(struct Expression const *expr)
{
if (!rpn_isSymbol(expr))
return NULL;
return sym_FindSymbol((char *)expr->tRPN + 1);
}
bool rpn_IsDiffConstant(struct Expression const *src, struct Symbol const *sym)
{
/* Check if both expressions only refer to a single symbol */
struct Symbol const *sym1 = rpn_SymbolOf(src);
if (!sym1 || !sym || sym1->type != SYM_LABEL || sym->type != SYM_LABEL)
return false;
return sym_GetSection(sym1) == sym_GetSection(sym);
}
static bool isDiffConstant(struct Expression const *src1,
struct Expression const *src2)
{
/* Check if both expressions only refer to a single symbol */
struct Symbol const *symbol1 = symbolOf(src1);
struct Symbol const *symbol2 = symbolOf(src2);
if (!symbol1 || !symbol2
|| symbol1->type != SYM_LABEL || symbol2->type != SYM_LABEL)
return false;
return sym_GetSection(symbol1) == sym_GetSection(symbol2);
return rpn_IsDiffConstant(src1, rpn_SymbolOf(src2));
}
void rpn_BinaryOp(enum RPNCommand op, struct Expression *expr,
@@ -428,8 +431,8 @@ void rpn_BinaryOp(enum RPNCommand op, struct Expression *expr,
}
} else if (op == RPN_SUB && isDiffConstant(src1, src2)) {
struct Symbol const *symbol1 = symbolOf(src1);
struct Symbol const *symbol2 = symbolOf(src2);
struct Symbol const *symbol1 = rpn_SymbolOf(src1);
struct Symbol const *symbol2 = rpn_SymbolOf(src2);
expr->nVal = sym_GetValue(symbol1) - sym_GetValue(symbol2);
expr->isKnown = true;

16
src/asm/section.c
View File

@@ -553,15 +553,21 @@ void out_PCRelByte(struct Expression *expr)
{
checkcodesection();
reserveSpace(1);
struct Symbol const *pc = sym_FindSymbol("@");
if (!rpn_isKnown(expr) || pCurrentSection->nOrg == -1) {
if (!rpn_IsDiffConstant(expr, pc)) {
createPatch(PATCHTYPE_JR, expr);
writebyte(0);
} else {
/* Target is relative to the byte *after* the operand */
uint16_t address = sym_GetPCValue() + 1;
/* The offset wraps (jump from ROM to HRAM, for loopexample) */
int16_t offset = expr->nVal - address;
struct Symbol const *sym = rpn_SymbolOf(expr);
/* The offset wraps (jump from ROM to HRAM, for example) */
int16_t offset;
/* Offset is relative to the byte *after* the operand */
if (sym == pc)
offset = -2; /* PC as operand to `jr` is lower than reference PC by 2 */
else
offset = sym_GetValue(sym) - (sym_GetValue(pc) + 1);
if (offset < -128 || offset > 127) {
yyerror("jr target out of reach (expected -129 < %" PRId16 " < 128)",