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| author | Quentin Carbonneaux <quentin@c9x.me> | 2017-08-17 04:47:10 -0400 |
|---|---|---|
| committer | Quentin Carbonneaux <quentin@c9x.me> | 2017-08-17 04:50:22 -0400 |
| commit | ae80e4f7caa6be31f83ae6a94a26ab3b60a5b064 (patch) | |
| tree | 46a064f691ca3aa20f4273facc164a3db91b64dd | |
| parent | 2b64b75c845d0491c7a701e44485d2856eeb686d (diff) | |
| download | roux-ae80e4f7caa6be31f83ae6a94a26ab3b60a5b064.tar.gz | |
fix bug in jumps simplification
In presence of jump loops, the algorithm would create cycles in the disjoint-set data structure. This caused infinite recursion and stack overflows.
| -rw-r--r-- | cfg.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/cfg.c b/cfg.c index ea1ae12..b1c80c7 100644 --- a/cfg.c +++ b/cfg.c @@ -304,8 +304,11 @@ simpljmp(Fn *fn) for (b=fn->start; b; b=b->link) { assert(!b->phi); if (b->nins == 0) - if (b->jmp.type == Jjmp) - uf[b->id] = b->s1; + if (b->jmp.type == Jjmp) { + uffind(&b->s1, uf); + if (b->s1 != b) + uf[b->id] = b->s1; + } } for (b=fn->start; b; b=b->link) { if (b->s1) |