diff options
| -rw-r--r-- | src/panfrost/midgard/compiler.h | 15 | ||||
| -rw-r--r-- | src/panfrost/midgard/midgard_compile.c | 57 |
2 files changed, 43 insertions, 29 deletions
diff --git a/src/panfrost/midgard/compiler.h b/src/panfrost/midgard/compiler.h index 2aad68f14dd..e35789fcfcd 100644 --- a/src/panfrost/midgard/compiler.h +++ b/src/panfrost/midgard/compiler.h @@ -160,11 +160,9 @@ typedef struct midgard_block { /* Number of quadwords _actually_ emitted, as determined after scheduling */ unsigned quadword_count; - /* Successors: always one forward (the block after us), maybe - * one backwards (for a backward branch). No need for a second - * forward, since graph traversal would get there eventually - * anyway */ - struct midgard_block *successors[2]; + /* Succeeding blocks. The compiler should not necessarily rely on + * source-order traversal */ + struct midgard_block *successors[4]; unsigned nr_successors; /* The successors pointer form a graph, and in the case of @@ -221,13 +219,12 @@ typedef struct compiler_context { int block_count; struct list_head blocks; - midgard_block *initial_block; - midgard_block *previous_source_block; - midgard_block *final_block; - /* List of midgard_instructions emitted for the current block */ midgard_block *current_block; + /* If there is a preset after block, use this, otherwise emit_block will create one if NULL */ + midgard_block *after_block; + /* The current "depth" of the loop, for disambiguating breaks/continues * when using nested loops */ int current_loop_depth; diff --git a/src/panfrost/midgard/midgard_compile.c b/src/panfrost/midgard/midgard_compile.c index 517eabedf32..4758677aa76 100644 --- a/src/panfrost/midgard/midgard_compile.c +++ b/src/panfrost/midgard/midgard_compile.c @@ -78,6 +78,15 @@ midgard_is_branch_unit(unsigned unit) static void midgard_block_add_successor(midgard_block *block, midgard_block *successor) { + assert(block); + assert(successor); + + /* Deduplicate */ + for (unsigned i = 0; i < block->nr_successors; ++i) { + if (block->successors[i] == successor) + return; + } + block->successors[block->nr_successors++] = successor; assert(block->nr_successors <= ARRAY_SIZE(block->successors)); } @@ -2082,7 +2091,12 @@ emit_fragment_epilogue(compiler_context *ctx) static midgard_block * emit_block(compiler_context *ctx, nir_block *block) { - midgard_block *this_block = calloc(sizeof(midgard_block), 1); + midgard_block *this_block = ctx->after_block; + ctx->after_block = NULL; + + if (!this_block) + this_block = calloc(sizeof(midgard_block), 1); + list_addtail(&this_block->link, &ctx->blocks); this_block->is_scheduled = false; @@ -2091,10 +2105,6 @@ emit_block(compiler_context *ctx, nir_block *block) ctx->texture_index[0] = -1; ctx->texture_index[1] = -1; - /* Add us as a successor to the block we are following */ - if (ctx->current_block) - midgard_block_add_successor(ctx->current_block, this_block); - /* Set up current block */ list_inithead(&this_block->instructions); ctx->current_block = this_block; @@ -2114,19 +2124,10 @@ emit_block(compiler_context *ctx, nir_block *block) } } - if (block == nir_start_block(ctx->func->impl)) - ctx->initial_block = this_block; - - if (block == nir_impl_last_block(ctx->func->impl)) - ctx->final_block = this_block; - /* Allow the next control flow to access us retroactively, for * branching etc */ ctx->current_block = this_block; - /* Document the fallthrough chain */ - ctx->previous_source_block = this_block; - return this_block; } @@ -2135,6 +2136,8 @@ static midgard_block *emit_cf_list(struct compiler_context *ctx, struct exec_lis static void emit_if(struct compiler_context *ctx, nir_if *nif) { + midgard_block *before_block = ctx->current_block; + /* Conditional branches expect the condition in r31.w; emit a move for * that in the _previous_ block (which is the current block). */ emit_condition(ctx, &nif->condition, true, COMPONENT_X); @@ -2143,8 +2146,9 @@ emit_if(struct compiler_context *ctx, nir_if *nif) EMIT(branch, true, true); midgard_instruction *then_branch = mir_last_in_block(ctx->current_block); - /* Emit the two subblocks */ + /* Emit the two subblocks. */ midgard_block *then_block = emit_cf_list(ctx, &nif->then_list); + midgard_block *end_then_block = ctx->current_block; /* Emit a jump from the end of the then block to the end of the else */ EMIT(branch, false, false); @@ -2155,6 +2159,7 @@ emit_if(struct compiler_context *ctx, nir_if *nif) int else_idx = ctx->block_count; int count_in = ctx->instruction_count; midgard_block *else_block = emit_cf_list(ctx, &nif->else_list); + midgard_block *end_else_block = ctx->current_block; int after_else_idx = ctx->block_count; /* Now that we have the subblocks emitted, fix up the branches */ @@ -2170,6 +2175,16 @@ emit_if(struct compiler_context *ctx, nir_if *nif) then_branch->branch.target_block = else_idx; then_exit->branch.target_block = after_else_idx; } + + /* Wire up the successors */ + + ctx->after_block = calloc(sizeof(midgard_block), 1); + + midgard_block_add_successor(before_block, then_block); + midgard_block_add_successor(before_block, else_block); + + midgard_block_add_successor(end_then_block, ctx->after_block); + midgard_block_add_successor(end_else_block, ctx->after_block); } static void @@ -2185,17 +2200,16 @@ emit_loop(struct compiler_context *ctx, nir_loop *nloop) int start_idx = ctx->block_count; /* Emit the body itself */ - emit_cf_list(ctx, &nloop->body); + midgard_block *loop_block = emit_cf_list(ctx, &nloop->body); /* Branch back to loop back */ struct midgard_instruction br_back = v_branch(false, false); br_back.branch.target_block = start_idx; emit_mir_instruction(ctx, br_back); - /* Mark down that branch in the graph. Note that we're really branching - * to the block *after* we started in. TODO: Why doesn't the branch - * itself have an off-by-one then...? */ - midgard_block_add_successor(ctx->current_block, start_block->successors[0]); + /* Mark down that branch in the graph. */ + midgard_block_add_successor(start_block, loop_block); + midgard_block_add_successor(ctx->current_block, loop_block); /* Find the index of the block about to follow us (note: we don't add * one; blocks are 0-indexed so we get a fencepost problem) */ @@ -2203,6 +2217,7 @@ emit_loop(struct compiler_context *ctx, nir_loop *nloop) /* Fix up the break statements we emitted to point to the right place, * now that we can allocate a block number for them */ + ctx->after_block = calloc(sizeof(midgard_block), 1); list_for_each_entry_from(struct midgard_block, block, start_block, &ctx->blocks, link) { mir_foreach_instr_in_block(block, ins) { @@ -2221,6 +2236,8 @@ emit_loop(struct compiler_context *ctx, nir_loop *nloop) ins->branch.target_type = TARGET_GOTO; ins->branch.target_block = break_block_idx; + + midgard_block_add_successor(block, ctx->after_block); } } |