return alu;
}
+static midgard_branch_extended
+midgard_create_branch_extended( midgard_condition cond,
+ midgard_jmp_writeout_op op,
+ unsigned dest_tag,
+ signed quadword_offset)
+{
+ /* The condition code is actually a LUT describing a function to
+ * combine multiple condition codes. However, we only support a single
+ * condition code at the moment, so we just duplicate over a bunch of
+ * times. */
+
+ uint16_t duplicated_cond =
+ (cond << 14) |
+ (cond << 12) |
+ (cond << 10) |
+ (cond << 8) |
+ (cond << 6) |
+ (cond << 4) |
+ (cond << 2) |
+ (cond << 0);
+
+ midgard_branch_extended branch = {
+ .op = op,
+ .dest_tag = dest_tag,
+ .offset = quadword_offset,
+ .cond = duplicated_cond
+ };
+
+ return branch;
+}
+
+static void
+emit_branch(midgard_instruction *ins,
+ compiler_context *ctx,
+ midgard_block *block,
+ midgard_bundle *bundle,
+ struct util_dynarray *emission)
+{
+ /* Parse some basic branch info */
+ bool is_compact = ins->unit == ALU_ENAB_BR_COMPACT;
+ bool is_conditional = ins->branch.conditional;
+ bool is_inverted = ins->branch.invert_conditional;
+ bool is_discard = ins->branch.target_type == TARGET_DISCARD;
+ bool is_tilebuf_wait = ins->branch.target_type == TARGET_TILEBUF_WAIT;
+ bool is_special = is_discard || is_tilebuf_wait;
+ bool is_writeout = ins->writeout;
+
+ /* Determine the block we're jumping to */
+ int target_number = ins->branch.target_block;
+
+ /* Report the destination tag */
+ int dest_tag = is_discard ? 0 :
+ is_tilebuf_wait ? bundle->tag :
+ midgard_get_first_tag_from_block(ctx, target_number);
+
+ /* Count up the number of quadwords we're
+ * jumping over = number of quadwords until
+ * (br_block_idx, target_number) */
+
+ int quadword_offset = 0;
+
+ if (is_discard) {
+ /* Ignored */
+ } else if (is_tilebuf_wait) {
+ quadword_offset = -1;
+ } else if (target_number > block->base.name) {
+ /* Jump forward */
+
+ for (int idx = block->base.name+1; idx < target_number; ++idx) {
+ midgard_block *blk = mir_get_block(ctx, idx);
+ assert(blk);
+
+ quadword_offset += blk->quadword_count;
+ }
+ } else {
+ /* Jump backwards */
+
+ for (int idx = block->base.name; idx >= target_number; --idx) {
+ midgard_block *blk = mir_get_block(ctx, idx);
+ assert(blk);
+
+ quadword_offset -= blk->quadword_count;
+ }
+ }
+
+ /* Unconditional extended branches (far jumps)
+ * have issues, so we always use a conditional
+ * branch, setting the condition to always for
+ * unconditional. For compact unconditional
+ * branches, cond isn't used so it doesn't
+ * matter what we pick. */
+
+ midgard_condition cond =
+ !is_conditional ? midgard_condition_always :
+ is_inverted ? midgard_condition_false :
+ midgard_condition_true;
+
+ midgard_jmp_writeout_op op =
+ is_discard ? midgard_jmp_writeout_op_discard :
+ is_tilebuf_wait ? midgard_jmp_writeout_op_tilebuffer_pending :
+ is_writeout ? midgard_jmp_writeout_op_writeout :
+ (is_compact && !is_conditional) ?
+ midgard_jmp_writeout_op_branch_uncond :
+ midgard_jmp_writeout_op_branch_cond;
+
+ if (is_compact) {
+ unsigned size = sizeof(midgard_branch_cond);
+
+ if (is_conditional || is_special) {
+ midgard_branch_cond branch = {
+ .op = op,
+ .dest_tag = dest_tag,
+ .offset = quadword_offset,
+ .cond = cond
+ };
+ memcpy(util_dynarray_grow_bytes(emission, size, 1), &branch, size);
+ } else {
+ assert(op == midgard_jmp_writeout_op_branch_uncond);
+ midgard_branch_uncond branch = {
+ .op = op,
+ .dest_tag = dest_tag,
+ .offset = quadword_offset,
+ .unknown = 1
+ };
+ assert(branch.offset == quadword_offset);
+ memcpy(util_dynarray_grow_bytes(emission, size, 1), &branch, size);
+ }
+ } else { /* `ins->compact_branch`, misnomer */
+ unsigned size = sizeof(midgard_branch_extended);
+
+ midgard_branch_extended branch =
+ midgard_create_branch_extended(
+ cond, op,
+ dest_tag,
+ quadword_offset);
+
+ memcpy(util_dynarray_grow_bytes(emission, size, 1), &branch, size);
+ }
+}
+
static void
emit_alu_bundle(compiler_context *ctx,
+ midgard_block *block,
midgard_bundle *bundle,
struct util_dynarray *emission,
unsigned lookahead)
mir_lower_roundmode(ins);
}
- if (ins->unit & UNITS_ANY_VECTOR) {
+ if (midgard_is_branch_unit(ins->unit)) {
+ emit_branch(ins, ctx, block, bundle, emission);
+ } else if (ins->unit & UNITS_ANY_VECTOR) {
midgard_vector_alu source = vector_alu_from_instr(ins);
mir_pack_mask_alu(ins, &source);
mir_pack_vector_srcs(ins, &source);
unsigned size = sizeof(source);
memcpy(util_dynarray_grow_bytes(emission, size, 1), &source, size);
- } else if (ins->unit == ALU_ENAB_BR_COMPACT) {
- uint16_t source = ins->br_compact;
- unsigned size = sizeof(source);
- memcpy(util_dynarray_grow_bytes(emission, size, 1), &source, size);
- } else if (ins->compact_branch) { /* misnomer */
- midgard_branch_extended source = ins->branch_extended;
- unsigned size = sizeof(source);
- memcpy(util_dynarray_grow_bytes(emission, size, 1), &source, size);
} else {
midgard_scalar_alu source = vector_to_scalar_alu(vector_alu_from_instr(ins), ins);
unsigned size = sizeof(source);
case TAG_ALU_8 + 4:
case TAG_ALU_12 + 4:
case TAG_ALU_16 + 4:
- emit_alu_bundle(ctx, bundle, emission, lookahead);
+ emit_alu_bundle(ctx, block, bundle, emission, lookahead);
break;
case TAG_LOAD_STORE_4: {