[cleanup] visualize register allocation before and after splintering

This also adds support in the c1 visualizer output generator to resolve
splintered live ranges before they have been merged back in.

Bug: v8:8238
Change-Id: I61e5f6da2e8b77ca9b42fae9004c77163d11960f
Reviewed-on: https://chromium-review.googlesource.com/c/1270817Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Stephan Herhut <herhut@chromium.org>
Cr-Commit-Position: refs/heads/master@{#56595}

src/compiler/graph-visualizer.cc

@@ -774,8 +774,11 @@ void GraphC1Visualizer::PrintLiveRange(const LiveRange* range, const char* type,
       }
     }
 
-    // The toplevel range is always suffixed with :0. Use that as parent.
-    os_ << " " << vreg << ":0";
+    // The toplevel range might be a splinter. Pre-resolve those here so that
+    // they have a proper parent.
+    const TopLevelLiveRange* parent = range->TopLevel();
+    if (parent->IsSplinter()) parent = parent->splintered_from();
+    os_ << " " << parent->vreg() << ":" << parent->relative_id();
 
     // TODO(herhut) Find something useful to print for the hint field
     os_ << " unknown";

src/compiler/pipeline.cc

@@ -2710,8 +2710,20 @@ void PipelineImpl::AllocateRegisters(const RegisterConfiguration* config,
               ->RangesDefinedInDeferredStayInDeferred());
   }
 
+  if (info()->trace_turbo_json_enabled() && !data->MayHaveUnverifiableGraph()) {
+    TurboCfgFile tcf(isolate());
+    tcf << AsC1VRegisterAllocationData("PreAllocation",
+                                       data->register_allocation_data());
+  }
+
   if (FLAG_turbo_preprocess_ranges) {
     Run<SplinterLiveRangesPhase>();
+    if (info()->trace_turbo_json_enabled() &&
+        !data->MayHaveUnverifiableGraph()) {
+      TurboCfgFile tcf(isolate());
+      tcf << AsC1VRegisterAllocationData("PostSplinter",
+                                         data->register_allocation_data());
+    }
   }
 
   Run<AllocateGeneralRegistersPhase<LinearScanAllocator>>();