v0.2.0: splats, copy/paste, faster homes, seat facing, and a full bug sweep

Frame Studio
- Gaussian splats (PLY, SPZ v2-v4), PLY vertex colours, panorama skies
- Copy, cut, paste and duplicate for objects, splats and world items
- Walkable-area rebake moved off the UI thread; viewport one frame sooner;
  refresh-locked pacing (FS_PACE=timer for the old one)
- Fixed: bundle thumbnail use-after-free crash, auto-save deleting
  environments, saves into scratch copies, edits lost on non-ASCII paths,
  unopenable manifests with inf/nan, bundle save data loss, opening a home
  marking it changed, gizmo NaN, long paths, many malformed-file crashes
- Updater verifies sha256, journals the swap and never leaves the exe missing

Frame Home
- Seats turn you to face their way
- Draw batching (Hand Tutorials up to ~20% less GPU time), cut-out EQUAL pass,
  late head-pose read before submit
- Proper queue-family hand-over to the compositor layer; layer descriptor
  generations and seqlocked slots; structural SPIR-V check
- Fixed: hangs/crashes on damaged .fenv files and shaders, render-pass
  validation error, sync hazard in the foveation smoothing pass, unverified
  update downloads, half-done installs

Tests: tests_loco/env_share/spv_check wired into CMake (FRAME_TESTS) and CI.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01VsaXGU27gsrXjDoFtyFJP9

third_party/spirv-tools/source/opt/code_sink.cpp

@@ -0,0 +1,326 @@
+// Copyright (c) 2019 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "code_sink.h"
+
+#include <vector>
+
+#include "source/opt/instruction.h"
+#include "source/opt/ir_context.h"
+#include "source/util/bit_vector.h"
+
+namespace spvtools {
+namespace opt {
+
+Pass::Status CodeSinkingPass::Process() {
+  bool modified = false;
+  for (Function& function : *get_module()) {
+    cfg()->ForEachBlockInPostOrder(function.entry().get(),
+                                   [&modified, this](BasicBlock* bb) {
+                                     if (SinkInstructionsInBB(bb)) {
+                                       modified = true;
+                                     }
+                                   });
+  }
+  return modified ? Status::SuccessWithChange : Status::SuccessWithoutChange;
+}
+
+bool CodeSinkingPass::SinkInstructionsInBB(BasicBlock* bb) {
+  bool modified = false;
+  for (auto inst = bb->rbegin(); inst != bb->rend(); ++inst) {
+    if (SinkInstruction(&*inst)) {
+      inst = bb->rbegin();
+      modified = true;
+    }
+  }
+  return modified;
+}
+
+bool CodeSinkingPass::SinkInstruction(Instruction* inst) {
+  if (inst->opcode() != spv::Op::OpLoad &&
+      inst->opcode() != spv::Op::OpAccessChain) {
+    return false;
+  }
+
+  if (ReferencesMutableMemory(inst)) {
+    return false;
+  }
+
+  if (BasicBlock* target_bb = FindNewBasicBlockFor(inst)) {
+    Instruction* pos = &*target_bb->begin();
+    while (pos->opcode() == spv::Op::OpPhi) {
+      pos = pos->NextNode();
+    }
+
+    inst->InsertBefore(pos);
+    context()->set_instr_block(inst, target_bb);
+    return true;
+  }
+  return false;
+}
+
+BasicBlock* CodeSinkingPass::FindNewBasicBlockFor(Instruction* inst) {
+  assert(inst->result_id() != 0 && "Instruction should have a result.");
+  BasicBlock* original_bb = context()->get_instr_block(inst);
+  BasicBlock* bb = original_bb;
+
+  std::unordered_set<uint32_t> bbs_with_uses;
+  get_def_use_mgr()->ForEachUse(
+      inst, [&bbs_with_uses, this](Instruction* use, uint32_t idx) {
+        if (use->opcode() != spv::Op::OpPhi) {
+          BasicBlock* use_bb = context()->get_instr_block(use);
+          if (use_bb) {
+            bbs_with_uses.insert(use_bb->id());
+          }
+        } else {
+          bbs_with_uses.insert(use->GetSingleWordOperand(idx + 1));
+        }
+      });
+
+  while (true) {
+    // If |inst| is used in |bb|, then |inst| cannot be moved any further.
+    if (bbs_with_uses.count(bb->id())) {
+      break;
+    }
+
+    // If |bb| has one successor (succ_bb), and |bb| is the only predecessor
+    // of succ_bb, then |inst| can be moved to succ_bb.  If succ_bb, has move
+    // then one predecessor, then moving |inst| into succ_bb could cause it to
+    // be executed more often, so the search has to stop.
+    if (bb->terminator()->opcode() == spv::Op::OpBranch) {
+      uint32_t succ_bb_id = bb->terminator()->GetSingleWordInOperand(0);
+      if (cfg()->preds(succ_bb_id).size() == 1) {
+        bb = context()->get_instr_block(succ_bb_id);
+        continue;
+      } else {
+        break;
+      }
+    }
+
+    // The remaining checks need to know the merge node.  If there is no merge
+    // instruction or an OpLoopMerge, then it is a break or continue.  We could
+    // figure it out, but not worth doing it now.
+    Instruction* merge_inst = bb->GetMergeInst();
+    if (merge_inst == nullptr ||
+        merge_inst->opcode() != spv::Op::OpSelectionMerge) {
+      break;
+    }
+
+    // Check all of the successors of |bb| it see which lead to a use of |inst|
+    // before reaching the merge node.
+    bool used_in_multiple_blocks = false;
+    uint32_t bb_used_in = 0;
+    bb->ForEachSuccessorLabel([this, bb, &bb_used_in, &used_in_multiple_blocks,
+                               &bbs_with_uses](uint32_t* succ_bb_id) {
+      if (IntersectsPath(*succ_bb_id, bb->MergeBlockIdIfAny(), bbs_with_uses)) {
+        if (bb_used_in == 0) {
+          bb_used_in = *succ_bb_id;
+        } else {
+          used_in_multiple_blocks = true;
+        }
+      }
+    });
+
+    // If more than one successor, which is not the merge block, uses |inst|
+    // then we have to leave |inst| in bb because there is none of the
+    // successors dominate all uses of |inst|.
+    if (used_in_multiple_blocks) {
+      break;
+    }
+
+    if (bb_used_in == 0) {
+      // If |inst| is not used before reaching the merge node, then we can move
+      // |inst| to the merge node.
+      bb = context()->get_instr_block(bb->MergeBlockIdIfAny());
+    } else {
+      // If the only successor that leads to a used of |inst| has more than 1
+      // predecessor, then moving |inst| could cause it to be executed more
+      // often, so we cannot move it.
+      if (cfg()->preds(bb_used_in).size() != 1) {
+        break;
+      }
+
+      // If |inst| is used after the merge block, then |bb_used_in| does not
+      // dominate all of the uses.  So we cannot move |inst| any further.
+      if (IntersectsPath(bb->MergeBlockIdIfAny(), original_bb->id(),
+                         bbs_with_uses)) {
+        break;
+      }
+
+      // Otherwise, |bb_used_in| dominates all uses, so move |inst| into that
+      // block.
+      bb = context()->get_instr_block(bb_used_in);
+    }
+    continue;
+  }
+  return (bb != original_bb ? bb : nullptr);
+}
+
+bool CodeSinkingPass::ReferencesMutableMemory(Instruction* inst) {
+  if (!inst->IsLoad()) {
+    return false;
+  }
+
+  Instruction* base_ptr = inst->GetBaseAddress();
+  if (base_ptr->opcode() != spv::Op::OpVariable) {
+    return true;
+  }
+
+  if (base_ptr->IsReadOnlyPointer()) {
+    return false;
+  }
+
+  if (HasUniformMemorySync()) {
+    return true;
+  }
+
+  if (spv::StorageClass(base_ptr->GetSingleWordInOperand(0)) !=
+      spv::StorageClass::Uniform) {
+    return true;
+  }
+
+  return HasPossibleStore(base_ptr);
+}
+
+bool CodeSinkingPass::HasUniformMemorySync() {
+  if (checked_for_uniform_sync_) {
+    return has_uniform_sync_;
+  }
+
+  bool has_sync = false;
+  get_module()->ForEachInst([this, &has_sync](Instruction* inst) {
+    switch (inst->opcode()) {
+      case spv::Op::OpMemoryBarrier: {
+        uint32_t mem_semantics_id = inst->GetSingleWordInOperand(1);
+        if (IsSyncOnUniform(mem_semantics_id)) {
+          has_sync = true;
+        }
+        break;
+      }
+      case spv::Op::OpControlBarrier:
+      case spv::Op::OpAtomicLoad:
+      case spv::Op::OpAtomicStore:
+      case spv::Op::OpAtomicExchange:
+      case spv::Op::OpAtomicIIncrement:
+      case spv::Op::OpAtomicIDecrement:
+      case spv::Op::OpAtomicIAdd:
+      case spv::Op::OpAtomicFAddEXT:
+      case spv::Op::OpAtomicISub:
+      case spv::Op::OpAtomicSMin:
+      case spv::Op::OpAtomicUMin:
+      case spv::Op::OpAtomicFMinEXT:
+      case spv::Op::OpAtomicSMax:
+      case spv::Op::OpAtomicUMax:
+      case spv::Op::OpAtomicFMaxEXT:
+      case spv::Op::OpAtomicAnd:
+      case spv::Op::OpAtomicOr:
+      case spv::Op::OpAtomicXor:
+      case spv::Op::OpAtomicFlagTestAndSet:
+      case spv::Op::OpAtomicFlagClear: {
+        uint32_t mem_semantics_id = inst->GetSingleWordInOperand(2);
+        if (IsSyncOnUniform(mem_semantics_id)) {
+          has_sync = true;
+        }
+        break;
+      }
+      case spv::Op::OpAtomicCompareExchange:
+      case spv::Op::OpAtomicCompareExchangeWeak:
+        if (IsSyncOnUniform(inst->GetSingleWordInOperand(2)) ||
+            IsSyncOnUniform(inst->GetSingleWordInOperand(3))) {
+          has_sync = true;
+        }
+        break;
+      default:
+        break;
+    }
+  });
+  has_uniform_sync_ = has_sync;
+  checked_for_uniform_sync_ = true;
+  return has_sync;
+}
+
+bool CodeSinkingPass::IsSyncOnUniform(uint32_t mem_semantics_id) const {
+  const analysis::Constant* mem_semantics_const =
+      context()->get_constant_mgr()->FindDeclaredConstant(mem_semantics_id);
+  assert(mem_semantics_const != nullptr &&
+         "Expecting memory semantics id to be a constant.");
+  assert(mem_semantics_const->AsIntConstant() &&
+         "Memory semantics should be an integer.");
+  uint32_t mem_semantics_int = mem_semantics_const->GetU32();
+
+  // If it does not affect uniform memory, then it is does not apply to uniform
+  // memory.
+  if ((mem_semantics_int & uint32_t(spv::MemorySemanticsMask::UniformMemory)) ==
+      0) {
+    return false;
+  }
+
+  // Check if there is an acquire or release.  If so not, this it does not add
+  // any memory constraints.
+  return (mem_semantics_int &
+          uint32_t(spv::MemorySemanticsMask::Acquire |
+                   spv::MemorySemanticsMask::AcquireRelease |
+                   spv::MemorySemanticsMask::Release)) != 0;
+}
+
+bool CodeSinkingPass::HasPossibleStore(Instruction* var_inst) {
+  assert(var_inst->opcode() == spv::Op::OpVariable ||
+         var_inst->opcode() == spv::Op::OpAccessChain ||
+         var_inst->opcode() == spv::Op::OpPtrAccessChain);
+
+  return get_def_use_mgr()->WhileEachUser(var_inst, [this](Instruction* use) {
+    switch (use->opcode()) {
+      case spv::Op::OpStore:
+        return true;
+      case spv::Op::OpAccessChain:
+      case spv::Op::OpPtrAccessChain:
+        return HasPossibleStore(use);
+      default:
+        return false;
+    }
+  });
+}
+
+bool CodeSinkingPass::IntersectsPath(uint32_t start, uint32_t end,
+                                     const std::unordered_set<uint32_t>& set) {
+  std::vector<uint32_t> worklist;
+  worklist.push_back(start);
+  std::unordered_set<uint32_t> already_done;
+  already_done.insert(start);
+
+  while (!worklist.empty()) {
+    BasicBlock* bb = context()->get_instr_block(worklist.back());
+    worklist.pop_back();
+
+    if (bb->id() == end) {
+      continue;
+    }
+
+    if (set.count(bb->id())) {
+      return true;
+    }
+
+    bb->ForEachSuccessorLabel([&already_done, &worklist](uint32_t* succ_bb_id) {
+      if (already_done.insert(*succ_bb_id).second) {
+        worklist.push_back(*succ_bb_id);
+      }
+    });
+  }
+  return false;
+}
+
+// namespace opt
+
+}  // namespace opt
+}  // namespace spvtools