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| author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2004-12-09 21:30:07 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-07 21:05:50 -0700 |
| commit | 0e23efe071d25eb48ef2b9f4b952cd11d5d95105 (patch) | |
| tree | 51eacd408cdfcf2c6525a3f6ce99228764e71ed4 | |
| parent | 6556b643f7a81474fbbbc4ae1b2ee793f36d0c56 (diff) | |
| download | sparse-dev-0e23efe071d25eb48ef2b9f4b952cd11d5d95105.tar.gz | |
Don't re-use registers for several different output storages.
We used to be lazy and just assume that if a value was in a
register when we exited, we could just use that register. Not
so, since now a register can contain multiple pseudos, that
may all need different output storages.
| -rw-r--r-- | example.c | 33 |
1 files changed, 27 insertions, 6 deletions
@@ -562,21 +562,41 @@ static void generate_one_insn(struct instruction *insn, struct bb_state *state) show_instruction(insn); } -static void write_reg_to_storage(struct bb_state *state, struct hardreg *reg, struct storage *storage) +static void write_reg_to_storage(struct bb_state *state, struct hardreg *reg, pseudo_t pseudo, struct storage *storage) { + int i; struct hardreg *out; switch (storage->type) { - case REG_UDEF: - storage->type = REG_REG; - storage->regno = reg - hardregs; - return; case REG_REG: out = hardregs + storage->regno; if (reg == out) return; printf("\tmovl %s,%s\n", reg->name, out->name); return; + case REG_UDEF: + if (reg->busy < 1000) { + storage->type = REG_REG; + storage->regno = reg - hardregs; + reg->busy = 1000; + return; + } + + /* Try to find a non-busy register.. */ + for (i = 0; i < REGNO; i++) { + out = hardregs + i; + if (out->busy) + continue; + printf("\tmovl %s,%s\n", reg->name, out->name); + storage->type = REG_REG; + storage->regno = i; + reg->busy = 1000; + return; + } + + /* Fall back on stack allocation ... */ + alloc_stack(state, storage); + /* Fallthroigh */ default: printf("\tmovl %s,%s\n", reg->name, show_memop(storage)); return; @@ -627,7 +647,7 @@ static void fill_output(struct bb_state *state, pseudo_t pseudo, struct storage FOR_EACH_PTR(reg->contains, p) { if (p == pseudo) { - write_reg_to_storage(state, reg, out); + write_reg_to_storage(state, reg, pseudo, out); return; } } END_FOR_EACH_PTR(p); @@ -670,6 +690,7 @@ static void generate_output_storage(struct bb_state *state) if (out->type == REG_REG) { struct hardreg *reg = hardregs + out->regno; pseudo_t p; + reg->busy = 1000; FOR_EACH_PTR(reg->contains, p) { if (p == entry->pseudo) goto ok; |