control_flow: Avoid adding unnecessary divergant blocks

This commit is contained in:
IndecisiveTurtle 2024-12-05 02:30:31 +02:00
parent 6244d00795
commit 29b51567ea
2 changed files with 28 additions and 15 deletions

View file

@ -47,6 +47,15 @@ static IR::Condition MakeCondition(const GcnInst& inst) {
}
}
static bool IgnoresExecMask(Opcode opcode) {
switch (opcode) {
case Opcode::V_WRITELANE_B32:
return true;
default:
return false;
}
}
static constexpr size_t LabelReserveSize = 32;
CFG::CFG(Common::ObjectPool<Block>& block_pool_, std::span<const GcnInst> inst_list_)
@ -133,20 +142,24 @@ void CFG::EmitDivergenceLabels() {
curr_begin = -1;
continue;
}
// Add a label to the instruction right after the open scope call.
// It is the start of a new basic block.
const auto& save_inst = inst_list[curr_begin];
const Label label = index_to_pc[curr_begin] + save_inst.length;
AddLabel(label);
// Add a label to the close scope instruction.
// There are 3 cases where we need to close a scope.
// * Close scope instruction inside the block
// * Close scope instruction at the end of the block (cbranch or endpgm)
// * Normal instruction at the end of the block
// For the last case we must NOT add a label as that would cause
// the instruction to be separated into its own basic block.
if (is_close) {
AddLabel(index_to_pc[index]);
// If all instructions in the scope ignore exec masking, we shouldn't insert a scope.
const auto start = inst_list.begin() + curr_begin + 1;
if (!std::ranges::all_of(start, inst_list.begin() + index, IgnoresExecMask, &GcnInst::opcode)) {
// Add a label to the instruction right after the open scope call.
// It is the start of a new basic block.
const auto& save_inst = inst_list[curr_begin];
const Label label = index_to_pc[curr_begin] + save_inst.length;
AddLabel(label);
// Add a label to the close scope instruction.
// There are 3 cases where we need to close a scope.
// * Close scope instruction inside the block
// * Close scope instruction at the end of the block (cbranch or endpgm)
// * Normal instruction at the end of the block
// For the last case we must NOT add a label as that would cause
// the instruction to be separated into its own basic block.
if (is_close) {
AddLabel(index_to_pc[index]);
}
}
// Reset scope begin.
curr_begin = -1;

View file

@ -702,7 +702,7 @@ Liverpool::Task Liverpool::ProcessCompute(std::span<const u32> acb, int vqid) {
false);
} else if (dma_data->src_sel == DmaDataSrc::Gds &&
dma_data->dst_sel == DmaDataDst::Memory) {
LOG_WARNING(Render_Vulkan, "GDS memory read");
// LOG_WARNING(Render_Vulkan, "GDS memory read");
} else if (dma_data->src_sel == DmaDataSrc::Memory &&
dma_data->dst_sel == DmaDataDst::Memory) {
rasterizer->InlineData(dma_data->DstAddress<VAddr>(),