diff options
Diffstat (limited to 'ir')
| -rw-r--r-- | ir/regalloc.c | 33 |
1 files changed, 25 insertions, 8 deletions
diff --git a/ir/regalloc.c b/ir/regalloc.c index 794cdd6..7056dfd 100644 --- a/ir/regalloc.c +++ b/ir/regalloc.c @@ -560,10 +560,19 @@ usereg(struct rega *ra, int reg, struct block *blk, int pos) static bool defreg(struct rega *ra, int reg, int pos) { if (rstest(mctarg->rglob, reg)) return 1; - for (struct fixinterval *fxit = ra->intervals.fixed; fxit; fxit = fxit->next) { + for (struct fixinterval *prev = NULL, *fxit = ra->intervals.fixed; fxit; prev = fxit, fxit = fxit->next) { if (fxit->rs == 1<<reg) { if (fxit->range.from <= pos) { fxit->range.from = pos; + struct fixinterval **at = &ra->intervals.fixed; + if ((*at)->range.from > pos) { + /* keep sorted */ + //DBG("moved %s\n", mctarg->rnames[reg]); + if (prev) prev->next = fxit->next; + while ((*at)->range.from < pos) at = &(*at)->next; + fxit->next = *at; + *at = fxit; + } //DBG(">>>def REG %s range %d-%d\n", mctarg->rnames[reg], fxit->range.from, fxit->range.to); return 1; } @@ -649,14 +658,21 @@ buildintervals(struct rega *ra) /* gather fixed intervals */ if (ins->op == Omove) { assert(ins->l.t == RREG); - if (ins->l.bits == ins->r.bits) /* special case `move Rx,Rx`: clobber reg, not a real use */ + if (ins->l.bits == ins->r.bits) {/* special case `move Rx,Rx`: clobber reg, not a real use */ usereg(ra, ins->l.i, blk, pos); + //DBG("@ %d clob %s\n", pos, mctarg->rnames[ins->l.i]); + } if (!defreg(ra, ins->l.i, pos)) { - /* dead register use. for example if - * move RCX, %1 - * %2 = shl 1, RCX - * and %2 is dead, the move to RCX can be killed */ - *ins = mkinstr(Onop,0,); + if (ins->keep) { /* clobber here */ + usereg(ra, ins->l.i, blk, pos); + assert(defreg(ra, ins->l.i, pos)); + } else { + /* dead register use. for example if + * move RCX, %1 + * %2 = shl 1, RCX + * and %2 is dead, the move to RCX can be killed */ + *ins = mkinstr(Onop,0,); + } } if (ins->l.bits == ins->r.bits) continue; @@ -917,7 +933,8 @@ linearscan(struct rega *ra) int end = itrange(current, current->nrange-1).to; /* exclude regs from overlapping fixed intervals */ - for (struct fixinterval *fxit = intervals->fixed; fxit; fxit = fxit->next) { + for (struct fixinterval *last = NULL, *fxit = intervals->fixed; fxit; last = fxit, fxit = fxit->next) { + if (last) assert(last->range.from <= fxit->range.from && "unsorted fixintervals"); if (fxit->range.to <= pos) { intervals->fixed = fxit->next; continue; |