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This commit is contained in:
Dmitry Stogov 2023-07-04 09:22:28 +03:00
parent 51d1bbbe09
commit 5eb09ce7a5
1 changed files with 15 additions and 6 deletions
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21
ir_ra.c
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@ -932,6 +932,7 @@ int ir_compute_live_ranges(ir_ctx *ctx)
live_in_block[v] = b; \
} while (0)
/* Returns the last virtual register alive at the end of the block (it is used as an already-visited marker) */
IR_ALWAYS_INLINE uint32_t ir_live_out_top(ir_ctx *ctx, uint32_t *live_outs, ir_list *live_lists, uint32_t b)
{
#if 0
@ -944,6 +945,7 @@ IR_ALWAYS_INLINE uint32_t ir_live_out_top(ir_ctx *ctx, uint32_t *live_outs, ir_l
#endif
}
/* Remember a virtual register alive at the end of the block */
IR_ALWAYS_INLINE void ir_live_out_push(ir_ctx *ctx, uint32_t *live_outs, ir_list *live_lists, uint32_t b, uint32_t v)
{
#if 0
@ -956,9 +958,10 @@ IR_ALWAYS_INLINE void ir_live_out_push(ir_ctx *ctx, uint32_t *live_outs, ir_list
if (live_lists->len >= live_lists->a.size) {
ir_array_grow(&live_lists->a, live_lists->a.size + 1024);
}
ir_list_push_unchecked(live_lists, live_outs[b]);
ir_list_push_unchecked(live_lists, v);
live_outs[b] = ir_list_len(live_lists) - 1;
/* Form a linked list of virtual register live at the end of the block */
ir_list_push_unchecked(live_lists, live_outs[b]); /* push old root of the list (previous element of the list) */
live_outs[b] = ir_list_len(live_lists); /* remember the new root */
ir_list_push_unchecked(live_lists, v); /* push a virtual register */
#endif
}
@ -977,6 +980,7 @@ static void ir_compute_live_sets(ir_ctx *ctx, uint32_t *live_outs, ir_list *live
ir_list_init(&fuse_queue, 16);
ir_list_init(&block_queue, 256);
/* For each virtual register explore paths from all uses to definition */
for (i = ctx->insns_count - 1; i > 0; i--) {
uint32_t v = ctx->vregs[i];
@ -985,6 +989,7 @@ static void ir_compute_live_sets(ir_ctx *ctx, uint32_t *live_outs, ir_list *live
ir_use_list *use_list = &ctx->use_lists[i];
ir_ref *p, n = use_list->count;
/* Collect all blocks where 'v' is used in a 'block_queue' */
for (p = &ctx->use_edges[use_list->refs]; n > 0; p++, n--) {
ir_ref use = *p;
ir_insn *insn = &ctx->ir_base[use];
@ -1032,13 +1037,14 @@ static void ir_compute_live_sets(ir_ctx *ctx, uint32_t *live_outs, ir_list *live
} else {
uint32_t use_block = ctx->cfg_map[use];
/* Check if the vitual register is alive at the start of 'use_block' */
if (def_block != use_block && ir_live_out_top(ctx, live_outs, live_lists, use_block) != v) {
ir_list_push(&block_queue, use_block);
}
}
}
/* UP_AND_MARK */
/* UP_AND_MARK: Traverse through predecessor blocks until we reache the block where 'v' is defined*/
while (ir_list_len(&block_queue)) {
uint32_t b = ir_list_pop(&block_queue);
ir_block *bb = &ctx->cfg_blocks[b];
@ -1061,7 +1067,9 @@ static void ir_compute_live_sets(ir_ctx *ctx, uint32_t *live_outs, ir_list *live
for (p = &ctx->cfg_edges[bb->predecessors]; n > 0; p++, n--) {
uint32_t pred_block = *p;
/* Check if 'pred_block' wasn't traversed before */
if (ir_live_out_top(ctx, live_outs, live_lists, pred_block) != v) {
/* Mark a virtual register 'v' alive at the end of 'pred_block' */
ir_live_out_push(ctx, live_outs, live_lists, pred_block, v);
if (pred_block != def_block) {
ir_list_push(&block_queue, pred_block);
@ -1266,6 +1274,7 @@ int ir_compute_live_ranges(ir_ctx *ctx)
bb = &ctx->cfg_blocks[b];
IR_ASSERT(!(bb->flags & IR_BB_UNREACHABLE));
/* For all virtual register alive at the end of the block */
n = live_outs[b];
while (n != 0) {
i = ir_list_at(&live_lists, n);
@ -1277,7 +1286,7 @@ int ir_compute_live_ranges(ir_ctx *ctx)
}
if (bb->successors_count == 1) {
/* for each phi function phi of successor */
/* for each phi function of the successor */
succ = ctx->cfg_edges[bb->successors];
succ_bb = &ctx->cfg_blocks[succ];
if (succ_bb->flags & IR_BB_HAS_PHI) {
@ -1304,7 +1313,7 @@ int ir_compute_live_ranges(ir_ctx *ctx)
}
}
/* for each operation op of b in reverse order */
/* for each operation of the block in reverse order */
ref = bb->end;
insn = &ctx->ir_base[ref];
if (insn->op == IR_END || insn->op == IR_LOOP_END) {