diff options
| -rw-r--r-- | yjit_core.c | 35 |
1 files changed, 17 insertions, 18 deletions
diff --git a/yjit_core.c b/yjit_core.c index 479a1e9020..17006f7b2c 100644 --- a/yjit_core.c +++ b/yjit_core.c @@ -418,13 +418,14 @@ uint8_t* gen_entry_point(const rb_iseq_t *iseq, uint32_t insn_idx, rb_execution_ // Called by the generated code when a branch stub is executed // Triggers compilation of branches and code patching static uint8_t * -branch_stub_hit(const uint32_t branch_idx, const uint32_t target_idx, rb_execution_context_t* ec) +branch_stub_hit(uint32_t branch_idx, uint32_t target_idx, rb_execution_context_t* ec) { uint8_t* dst_addr; + // Stop other ractors since we are going to patch machine code. + // This is how the GC does it. RB_VM_LOCK_ENTER(); - rb_vm_barrier(); // Stop other ractors since we are going to patch machine code. - // It's how the GC does it. + rb_vm_barrier(); RUBY_ASSERT(branch_idx < num_branches); RUBY_ASSERT(target_idx < 2); @@ -454,6 +455,18 @@ branch_stub_hit(const uint32_t branch_idx, const uint32_t target_idx, rb_executi // If this block hasn't yet been compiled if (!p_block) { + // If the new block will be placed next right after the branch + if (cb->write_pos == branch->end_pos) { + //fprintf(stderr, "target idx %d will be placed next\n", target_idx); + branch->shape = (uint8_t)target_idx; + + // Rewrite the branch with the new, potentially more compact shape + cb_set_pos(cb, branch->start_pos); + branch->gen_fn(cb, branch->dst_addrs[0], branch->dst_addrs[1], branch->shape); + RUBY_ASSERT(cb->write_pos <= branch->end_pos && "can't enlarge branches"); + branch->end_pos = cb->write_pos; + } + // Limit the number of block versions ctx_t generic_ctx = DEFAULT_CTX; generic_ctx.stack_size = target_ctx->stack_size; @@ -475,26 +488,12 @@ branch_stub_hit(const uint32_t branch_idx, const uint32_t target_idx, rb_executi dst_addr = cb_get_ptr(cb, p_block->start_pos); branch->dst_addrs[target_idx] = dst_addr; - // Adjust brach shape based on block placement relative to the branch - if (branch->end_pos == p_block->start_pos) { - branch->shape = (branch_shape_t)target_idx; - } - // Rewrite the branch with the new jump target address RUBY_ASSERT(branch->dst_addrs[0] != NULL); uint32_t cur_pos = cb->write_pos; cb_set_pos(cb, branch->start_pos); branch->gen_fn(cb, branch->dst_addrs[0], branch->dst_addrs[1], branch->shape); - RUBY_ASSERT(cb->write_pos <= branch->end_pos && "can't enlarge a branch"); - - // If the branch got smaller - if (cb->write_pos < branch->end_pos) { - // fill the difference with nops - uint32_t shrinkage = branch->end_pos - cb->write_pos; - nop(cb, shrinkage); - } - - // Done patching the branch. Restore write position. + RUBY_ASSERT(cb->write_pos == branch->end_pos); cb_set_pos(cb, cur_pos); // Restore interpreter sp, since the code hitting the stub expects the original. |