shader: own control flow on IR blocks with direct targets

This commit is contained in:
nmzik
2026-10-09 01:59:41 +02:00
parent 8abf99c56e
commit 3df456675d
13 changed files with 477 additions and 472 deletions
@@ -83,44 +83,31 @@ void StoreDispatcherPhiEdge(ValueEmitContext& ctx, const DispatcherFunctionState
}
}
const IR::Block* TargetBlock(const IR::Program& program, uint32_t id) {
const auto found = std::ranges::find_if(
program.block_info, [&](const IR::BlockInfo& info) { return info.id == id; });
if (found == program.block_info.end()) {
return nullptr;
}
return program.blocks[static_cast<size_t>(found - program.block_info.begin())];
}
void EmitReturn(ValueEmitContext& ctx) {
EmitKillIfPixelValidMaskInactive(ctx.state);
ctx.state.builder.AddFunction(spv::OpReturn);
}
void EmitStructuredTerminator(ValueEmitContext& ctx, const IR::Block* block,
const IR::BlockInfo& info) {
const auto& program = ctx.state.program;
const auto& term = info.terminator;
void EmitStructuredTerminator(ValueEmitContext& ctx, const IR::Block* block) {
const auto& term = block->terminator;
const auto emit_merge = [&]() {
if (term.loop_header) {
const auto* merge = TargetBlock(program, term.merge_block);
const auto* cont = TargetBlock(program, term.continue_block);
const auto* merge = term.merge_block;
const auto* cont = term.continue_block;
if (merge != nullptr && cont != nullptr) {
ctx.state.builder.AddFunction(spv::OpLoopMerge, merge->Definition(),
cont->Definition(), spv::LoopControlMaskNone);
}
} else if (term.kind == CFG::TerminatorKind::ConditionalBranch &&
term.merge_block != UINT32_MAX) {
if (const auto* merge = TargetBlock(program, term.merge_block); merge != nullptr) {
ctx.state.builder.AddFunction(spv::OpSelectionMerge, merge->Definition(),
spv::SelectionControlMaskNone);
}
term.merge_block != nullptr) {
ctx.state.builder.AddFunction(spv::OpSelectionMerge, term.merge_block->Definition(),
spv::SelectionControlMaskNone);
}
};
switch (term.kind) {
case CFG::TerminatorKind::Branch: {
const auto* target = TargetBlock(program, term.true_block);
const auto* target = term.true_block;
if (target == nullptr) {
EmitReturn(ctx);
return;
@@ -130,13 +117,13 @@ void EmitStructuredTerminator(ValueEmitContext& ctx, const IR::Block* block,
return;
}
case CFG::TerminatorKind::ConditionalBranch: {
const auto* true_block = TargetBlock(program, term.true_block);
const auto* false_block = TargetBlock(program, term.false_block);
if (true_block == nullptr || false_block == nullptr || info.condition.IsEmpty()) {
const auto* true_block = term.true_block;
const auto* false_block = term.false_block;
if (true_block == nullptr || false_block == nullptr || block->condition.IsEmpty()) {
EmitReturn(ctx);
return;
}
const auto condition = ctx.Def(info.condition);
const auto condition = ctx.Def(block->condition);
emit_merge();
ctx.state.builder.AddFunction(spv::OpBranchConditional, condition,
true_block->Definition(), false_block->Definition());
@@ -147,8 +134,7 @@ void EmitStructuredTerminator(ValueEmitContext& ctx, const IR::Block* block,
}
void EmitDispatcherTarget(ValueEmitContext& ctx, const DispatcherFunctionState& dispatcher,
const IR::Block* from, uint32_t target) {
const auto* block = TargetBlock(ctx.state.program, target);
const IR::Block* from, const IR::Block* block) {
if (block != nullptr) {
StoreDispatcherPhiEdge(ctx, dispatcher, from, block);
if (ctx.other_half != nullptr) {
@@ -158,41 +144,37 @@ void EmitDispatcherTarget(ValueEmitContext& ctx, const DispatcherFunctionState&
}
uint32_t EmitDispatcherNextPc(ValueEmitContext& ctx, const DispatcherFunctionState& dispatcher,
const IR::Block* block, const IR::BlockInfo& info) {
const auto& term = info.terminator;
const IR::Block* block) {
const auto& term = block->terminator;
switch (term.kind) {
case CFG::TerminatorKind::Branch:
EmitDispatcherTarget(ctx, dispatcher, block, term.true_block);
return ConstantU32(ctx.state, term.true_block);
return ConstantU32(ctx.state, term.true_block->id);
case CFG::TerminatorKind::ConditionalBranch: {
EmitDispatcherTarget(ctx, dispatcher, block, term.true_block);
EmitDispatcherTarget(ctx, dispatcher, block, term.false_block);
const auto selected = ctx.state.builder.AllocateId();
ctx.state.builder.AddFunction(
spv::OpSelect, TypeU32(ctx.state), selected, ctx.Def(info.condition),
ConstantU32(ctx.state, term.true_block), ConstantU32(ctx.state, term.false_block));
ctx.state.builder.AddFunction(spv::OpSelect, TypeU32(ctx.state), selected,
ctx.Def(block->condition),
ConstantU32(ctx.state, term.true_block->id),
ConstantU32(ctx.state, term.false_block->id));
return selected;
}
case CFG::TerminatorKind::IndirectBranch: {
for (const auto target: term.indirect_targets) {
for (const auto* target: block->ImmSuccessors()) {
EmitDispatcherTarget(ctx, dispatcher, block, target);
}
uint32_t selected = ConstantU32(ctx.state, UINT32_MAX);
if (!info.indirect_target.IsEmpty()) {
const auto selector = ctx.Def(info.indirect_target);
const auto& values = term.indirect_selector_code != UINT32_MAX
? term.indirect_selector_values
: term.indirect_target_pcs;
const auto& targets = term.indirect_selector_code != UINT32_MAX
? term.indirect_selector_targets
: term.indirect_targets;
for (size_t index = 0; index < std::min(values.size(), targets.size()); index++) {
if (!block->indirect_target.IsEmpty()) {
const auto selector = ctx.Def(block->indirect_target);
for (const auto& branch: term.cases) {
const auto match = ctx.state.builder.AllocateId();
const auto next = ctx.state.builder.AllocateId();
ctx.state.builder.AddFunction(spv::OpIEqual, TypeBool(ctx.state), match,
selector, ConstantU32(ctx.state, values[index]));
selector, ConstantU32(ctx.state, branch.value));
ctx.state.builder.AddFunction(spv::OpSelect, TypeU32(ctx.state), next, match,
ConstantU32(ctx.state, targets[index]), selected);
ConstantU32(ctx.state, branch.target->id),
selected);
selected = next;
}
}
@@ -349,7 +331,7 @@ void EmitStructuredFunction(ValueEmitContext& ctx) {
EmitStructuredInstruction(lane, structured, inst);
});
structured.block_exit_labels.emplace(block, ctx.state.current_label);
EmitStructuredTerminator(ctx, block, program.block_info[index]);
EmitStructuredTerminator(ctx, block);
}
PatchStructuredPhis(ctx, structured);
}
@@ -361,8 +343,7 @@ void EmitDispatcherFunction(ValueEmitContext& ctx, const DispatcherFunctionState
EmitBlock(ctx, entry, [&](ValueEmitContext& lane, const IR::Inst& inst) {
EmitDispatcherInstruction(lane, dispatcher, inst);
});
const auto initial_pc =
EmitDispatcherNextPc(ctx, dispatcher, entry, state.program.block_info.front());
const auto initial_pc = EmitDispatcherNextPc(ctx, dispatcher, entry);
const auto initial_parent = state.current_label;
state.builder.AddFunction(spv::OpBranch, dispatcher.header_label);
@@ -384,7 +365,7 @@ void EmitDispatcherFunction(ValueEmitContext& ctx, const DispatcherFunctionState
spv::SelectionControlMaskNone);
std::vector<uint32_t> words {spv::OpSwitch, pc, dispatcher.after_switch_label};
for (size_t index = 1; index < state.program.blocks.size(); index++) {
words.push_back(state.program.block_info[index].id);
words.push_back(state.program.blocks[index]->id);
words.push_back(state.program.blocks[index]->Definition());
}
state.builder.AddFunction(words);
@@ -396,8 +377,7 @@ void EmitDispatcherFunction(ValueEmitContext& ctx, const DispatcherFunctionState
[&](ValueEmitContext& lane, const IR::Inst& inst) {
EmitDispatcherInstruction(lane, dispatcher, inst);
});
const auto selected = EmitDispatcherNextPc(ctx, dispatcher, state.program.blocks[index],
state.program.block_info[index]);
const auto selected = EmitDispatcherNextPc(ctx, dispatcher, state.program.blocks[index]);
next_pc_words.push_back(selected);
next_pc_words.push_back(state.current_label);
state.builder.AddFunction(spv::OpBranch, dispatcher.after_switch_label);
@@ -668,8 +648,8 @@ void EmitProgram(EmitterState& state) {
}
}
for (size_t index = 0; index < program.blocks.size(); index++) {
mark_cross_block(program.block_info[index].condition, program.blocks[index]);
mark_cross_block(program.block_info[index].indirect_target, program.blocks[index]);
mark_cross_block(program.blocks[index]->condition, program.blocks[index]);
mark_cross_block(program.blocks[index]->indirect_target, program.blocks[index]);
}
dispatch.header_label = state.builder.AllocateId();
dispatch.select_label = state.builder.AllocateId();