basic impl

This commit is contained in:
Fire Cube 2025-04-21 00:19:00 +02:00
parent ddf3df7f56
commit 005cec9f46
3 changed files with 60 additions and 8 deletions

View File

@ -67,6 +67,42 @@ static bool IgnoresExecMask(const GcnInst& inst) {
return false;
}
static std::optional<u32> ResolveSetPcTarget(std::span<const GcnInst> list, u32 setpc_index,
std::span<const u32> pc_map) {
if (setpc_index < 3)
return std::nullopt;
const auto& getpc = list[setpc_index - 3];
const auto& arith = list[setpc_index - 2];
const auto& setpc = list[setpc_index];
if (getpc.opcode != Opcode::S_GETPC_B64 ||
!(arith.opcode == Opcode::S_ADD_U32 || arith.opcode == Opcode::S_SUB_U32) ||
setpc.opcode != Opcode::S_SETPC_B64)
return std::nullopt;
// RegisterPaar prüfen
if (getpc.dst[0].code != setpc.src[0].code || arith.dst[0].code != setpc.src[0].code)
return std::nullopt;
// Sofortwert holen
if (arith.src_count < 2 || arith.src[1].field != OperandField::LiteralConst)
return std::nullopt;
const u32 imm = arith.src[1].code;
// Vorzeichenbehafteter Offset
const s32 signed_offset =
(arith.opcode == Opcode::S_ADD_U32) ? static_cast<s32>(imm) : -static_cast<s32>(imm);
const u32 base_pc = pc_map[setpc_index - 3] + getpc.length;
const u32 result_pc = static_cast<u32>(static_cast<s32>(base_pc) + signed_offset);
return result_pc & ~0x3u; // DWORD-aligned PC
}
static constexpr size_t LabelReserveSize = 32;
CFG::CFG(Common::ObjectPool<Block>& block_pool_, std::span<const GcnInst> inst_list_)
@ -89,19 +125,22 @@ void CFG::EmitLabels() {
index_to_pc[i] = pc;
const GcnInst inst = inst_list[i];
if (inst.IsUnconditionalBranch()) {
const u32 target = inst.BranchTarget(pc);
AddLabel(target);
// Emit this label so that the block ends with s_branch instruction
AddLabel(pc + inst.length);
u32 target = inst.BranchTarget(pc);
if (inst.opcode == Opcode::S_SETPC_B64) {
if (auto t = ResolveSetPcTarget(inst_list, i, index_to_pc))
target = *t;
}
AddLabel(target); // Ziel
AddLabel(pc + inst.length); // FallthroughLabel
} else if (inst.IsConditionalBranch()) {
const u32 true_label = inst.BranchTarget(pc);
const u32 false_label = pc + inst.length;
AddLabel(true_label);
AddLabel(false_label);
} else if (inst.opcode == Opcode::S_ENDPGM) {
const u32 next_label = pc + inst.length;
AddLabel(next_label);
AddLabel(pc + inst.length);
}
pc += inst.length;
}
index_to_pc[inst_list.size()] = pc;
@ -280,7 +319,18 @@ void CFG::LinkBlocks() {
// Find the branch targets from the instruction and link the blocks.
// Note: Block end address is one instruction after end_inst.
const u32 branch_pc = block.end - end_inst.length;
const u32 target_pc = end_inst.BranchTarget(branch_pc);
u32 target_pc = 0;
if (end_inst.opcode == Opcode::S_SETPC_B64) {
auto tgt = ResolveSetPcTarget(inst_list, block.end_index, index_to_pc);
ASSERT_MSG(tgt,
"S_SETPC_B64 ohne auflösbaren Offset bei PC {:#x} (Index {}): Beteiligte "
"Instruktionen nicht erkannt oder ungültiges Muster",
branch_pc, block.end_index);
target_pc = *tgt;
} else {
target_pc = end_inst.BranchTarget(branch_pc);
}
if (end_inst.IsUnconditionalBranch()) {
auto* target_block = get_block(target_pc);
++target_block->num_predecessors;

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@ -18,7 +18,7 @@ bool GcnInst::IsTerminateInstruction() const {
}
bool GcnInst::IsUnconditionalBranch() const {
return opcode == Opcode::S_BRANCH;
return opcode == Opcode::S_BRANCH or opcode == Opcode::S_SETPC_B64;
}
bool GcnInst::IsFork() const {

View File

@ -18,6 +18,8 @@ void Translator::EmitFlowControl(u32 pc, const GcnInst& inst) {
return;
case Opcode::S_GETPC_B64:
return S_GETPC_B64(pc, inst);
case Opcode::S_SETPC_B64:
return;
case Opcode::S_WAITCNT:
case Opcode::S_NOP:
case Opcode::S_ENDPGM: