[analysis] Make it easier to implement a transfer function (#6077)

Combine the `transfer` and `getDependents` methods of a transfer function so
that a transfer function only has to implement `transfer`, which now returns a
range of basic blocks that may need to be re-analyzed.

To make it easier to implement the returned basic block range, change the
requirement so that it provides iterators to `const BasicBlock*` rather than
`BasicBlock`. This allows us to entirely remove cfg-impl.h.

1 files changed, 6 insertions, 6 deletions

diff --git a/src/analysis/cfg.cpp b/src/analysis/cfg.cpp
index 0d651526b..ba638ec5a 100644
--- a/src/analysis/cfg.cpp
+++ b/src/analysis/cfg.cpp
@@ -80,19 +80,19 @@ void CFG::print(std::ostream& os, Module* wasm) const {
 
 void BasicBlock::print(std::ostream& os, Module* wasm, size_t start) const {
   os << ";; preds: [";
-  for (auto& pred : preds()) {
-    if (&pred != &*preds().begin()) {
+  for (const auto* pred : preds()) {
+    if (pred != *preds().begin()) {
       os << ", ";
     }
-    os << pred.index;
+    os << pred->index;
   }
   os << "], succs: [";
 
-  for (auto& succ : succs()) {
-    if (&succ != &*succs().begin()) {
+  for (const auto* succ : succs()) {
+    if (succ != *succs().begin()) {
       os << ", ";
     }
-    os << succ.index;
+    os << succ->index;
   }
   os << "]\n";