Refactor interaction between Pass and PassRunner (#5093)

Previously only WalkerPasses had access to the `getPassRunner` and
`getPassOptions` methods. Move those methods to `Pass` so all passes can use
them. As a result, the `PassRunner` passed to `Pass::run` and
`Pass::runOnFunction` is no longer necessary, so remove it.

Also update `Pass::create` to return a unique_ptr, which is more efficient than
having it return a raw pointer only to have the `PassRunner` wrap that raw
pointer in a `unique_ptr`.

Delete the unused template `PassRunner::getLast()`, which looks like it was
intended to enable retrieving previous analyses and has been in the code base
since 2015 but is not implemented anywhere.

1 files changed, 12 insertions, 6 deletions

diff --git a/src/passes/pass.cpp b/src/passes/pass.cpp
index c548b66c5..4036b8f47 100644
--- a/src/passes/pass.cpp
+++ b/src/passes/pass.cpp
@@ -896,7 +896,11 @@ void PassRunner::runPass(Pass* pass) {
     checker = std::unique_ptr<AfterEffectModuleChecker>(
       new AfterEffectModuleChecker(wasm));
   }
-  pass->run(this, wasm);
+  // Passes can only be run once and we deliberately do not clear the pass
+  // runner after running the pass, so there must not already be a runner here.
+  assert(!pass->getPassRunner());
+  pass->setPassRunner(this);
+  pass->run(wasm);
   handleAfterEffects(pass);
   if (getPassDebug()) {
     checker->check();
@@ -925,15 +929,17 @@ void PassRunner::runPassOnFunction(Pass* pass, Function* func) {
     bodyBefore << *func->body << '\n';
   }
 
-  // function-parallel passes get a new instance per function
-  auto instance = std::unique_ptr<Pass>(pass->create());
   std::unique_ptr<AfterEffectFunctionChecker> checker;
   if (passDebug) {
-    checker = std::unique_ptr<AfterEffectFunctionChecker>(
-      new AfterEffectFunctionChecker(func));
+    checker = std::make_unique<AfterEffectFunctionChecker>(func);
   }
-  instance->runOnFunction(this, wasm, func);
+
+  // Function-parallel passes get a new instance per function
+  auto instance = pass->create();
+  instance->setPassRunner(this);
+  instance->runOnFunction(wasm, func);
   handleAfterEffects(pass, func);
+
   if (passDebug) {
     checker->check();
   }