Fix bugs and emit guards for latches that cut through and go to loop headers that are not immediate parent

Author: VedantParanjape

include/blocks/loops.h

@@ -7,10 +7,11 @@
 #include <unordered_set>
 
 using namespace block;
+class loop_info;
 class loop {
 public:
     loop(std::shared_ptr<basic_block> header): header_block(header) {}
-    stmt::Ptr convert_to_ast_impl(dominator_analysis &dta_, std::vector<std::pair<std::shared_ptr<basic_block>, stmt_block::Ptr>> &return_blocks);
+    stmt::Ptr convert_to_ast_impl(loop_info &li, dominator_analysis &dta_, std::vector<std::pair<std::shared_ptr<basic_block>, stmt_block::Ptr>> &return_blocks, stmt::Ptr &jump_condition_def, stmt::Ptr &jump_condition_block);
 
     struct loop_bounds_ {
         stmt::Ptr ind_var;
@@ -33,6 +34,7 @@ class loop {
     basic_block::cfg_block loop_latch_blocks;
     basic_block::cfg_block loop_exit_blocks;
     std::vector<std::shared_ptr<loop>> subloops;
+    while_stmt::Ptr structured_ast_loop;
 };
 
 class loop_info {

src/blocks/basic_blocks.cpp

@@ -96,7 +96,7 @@ basic_block::cfg_block generate_basic_blocks(block::stmt_block::Ptr ast) {
             work_list.pop_front();
             // push the exit block to the work_list
             work_list.push_front(exit_bb);
-
+            std::cerr << "inside if handler: " << bb->name << "\n";
             // if there is a then_stmt, create a basic block for it
             if (to<stmt_block>(if_stmt_->then_stmt)->stmts.size() != 0) {
                 auto then_bb = std::make_shared<basic_block>(std::to_string(++basic_block_count));
@@ -112,6 +112,7 @@ basic_block::cfg_block generate_basic_blocks(block::stmt_block::Ptr ast) {
                 bb->then_branch = then_bb;
                 // push the block to the work_list, to expand it further
                 work_list.push_front(then_bb);
+                std::cerr << "inside then" << "\n";
             }
             // if there is a else_stmt, create a basic block for it
             if (to<stmt_block>(if_stmt_->else_stmt)->stmts.size() != 0) {
@@ -128,6 +129,7 @@ basic_block::cfg_block generate_basic_blocks(block::stmt_block::Ptr ast) {
                 bb->else_branch = else_bb;
                 // push the block to the work_list, to expand it further
                 work_list.insert(work_list.begin() + 1, else_bb);
+                std::cerr << "inside else" << "\n";
             }
 
             // if there is no then/else block, then have the exit block as successor as well.