[Decompiler] Put likely delay slots in their own block (#237)

* first part of fix

* atomic op conversion fix

* update tests

* oops

decompiler/Function/BasicBlocks.cpp

@@ -23,7 +23,7 @@ std::vector<BasicBlock> find_blocks_in_function(const LinkedObjectFile& file,
     const auto& instr = func.instructions.at(i);
     const auto& instr_info = instr.get_info();
 
-    if (instr_info.is_branch || instr_info.is_branch_likely) {
+    if (instr_info.is_branch && !instr_info.is_branch_likely) {
       // make sure the delay slot of this branch is included in the function
       assert(i + func.start_word < func.end_word - 1);
       // divider after delay slot
@@ -37,6 +37,24 @@ std::vector<BasicBlock> find_blocks_in_function(const LinkedObjectFile& file,
       assert(label.offset / 4 < func.end_word - 1);
       dividers.push_back(label.offset / 4 - func.start_word);
     }
+
+    // for branch likely, we treat the likely instruction as a separate block.
+    if (instr_info.is_branch_likely) {
+      assert(i + func.start_word < func.end_word - 1);
+      // divider after branch instruction
+      dividers.push_back(i + 1);
+      // divider after likely delay slot.
+      dividers.push_back(i + 2);
+      // divider at the destination.
+      auto label_id = instr.get_label_target();
+      assert(label_id != -1);
+      const auto& label = file.labels.at(label_id);
+      // should only jump to within our own function
+      assert(label.target_segment == seg);
+      assert(label.offset / 4 > func.start_word);
+      assert(label.offset / 4 < func.end_word - 1);
+      dividers.push_back(label.offset / 4 - func.start_word);
+    }
   }
 
   std::sort(dividers.begin(), dividers.end());