add shared loop creation helpers

add shared checked arithmetic helpers
refactor pim passes into Pim/Transforms
more robust memory coalescing pass

src/PIM/Compiler/PimCompilerUtils.cpp

@@ -40,7 +40,6 @@ void addPassesPim(OwningOpRef<ModuleOp>& module,
 
   if (pimEmissionTarget >= EmitPimBufferized) {
     pm.addPass(createPimBufferizationPass());
-    pm.addPass(createPimStaticMemoryCoalescingPass());
     pm.addPass(createMessagePass("Pim bufferized"));
   }
 
@@ -48,6 +47,7 @@ void addPassesPim(OwningOpRef<ModuleOp>& module,
     pm.addPass(createPimHostConstantFoldingPass());
     pm.addPass(createMessagePass("Pim host constants folded"));
     pm.addPass(createPimMaterializeHostConstantsPass());
+    pm.addPass(createPimMemoryCoalescingPass());
     pm.addPass(createPimVerificationPass());
     pm.addPass(createMessagePass("Pim verified"));
     pm.addPass(createEmitPimCodePass());