[turbofan]: Improved source position information

src/compiler/simplified-lowering.cc

Index: src/compiler/simplified-lowering.cc
diff --git a/src/compiler/simplified-lowering.cc b/src/compiler/simplified-lowering.cc
index de33f9611ee25831b5669c8439f6446de46e4713..217e5a5bd055d0dc02830163ae703ee708c92119 100644
--- a/src/compiler/simplified-lowering.cc
+++ b/src/compiler/simplified-lowering.cc
@@ -17,6 +17,7 @@
 #include "src/compiler/representation-change.h"
 #include "src/compiler/simplified-lowering.h"
 #include "src/compiler/simplified-operator.h"
+#include "src/compiler/source-position.h"
 #include "src/objects.h"
 
 namespace v8 {
@@ -65,7 +66,8 @@ class RepresentationSelector {
   };
 
   RepresentationSelector(JSGraph* jsgraph, Zone* zone,
-                         RepresentationChanger* changer)
+                         RepresentationChanger* changer,
+                         SourcePositionTable* source_positions)
       : jsgraph_(jsgraph),
         count_(jsgraph->graph()->NodeCount()),
         info_(zone->NewArray<NodeInfo>(count_)),
@@ -73,7 +75,8 @@ class RepresentationSelector {
         replacements_(zone),
         phase_(PROPAGATE),
         changer_(changer),
-        queue_(zone) {
+        queue_(zone),
+        source_positions_(source_positions) {
     memset(info_, 0, sizeof(NodeInfo) * count_);
 
     safe_int_additive_range_ =
@@ -92,6 +95,8 @@ class RepresentationSelector {
       queue_.pop();
       info->queued = false;
       TRACE((" visit #%d: %s\n", node->id(), node->op()->mnemonic()));
+      SourcePositionTable::Scope scope(

[titzer, 2015/02/04 13:23:44]

You shouldn't need the scope during the propagation phase.

[danno, 2015/02/04 13:42:17]

Done.

+          source_positions_, source_positions_->GetSourcePosition(node));
       VisitNode(node, info->use, NULL);
       TRACE(("  ==> output "));
       PrintInfo(info->output);
@@ -454,10 +459,21 @@ class RepresentationSelector {
     return (use & (kTypeInt32 | kTypeNumber | kTypeAny)) != 0;
   }
 
-  // Dispatching routine for visiting the node {node} with the usage {use}.
-  // Depending on the operator, propagate new usage info to the inputs.
   void VisitNode(Node* node, MachineTypeUnion use,

[titzer, 2015/02/04 13:23:44]

I'd rather see this inlined into the second loop (or two loop versions) in the
Run() method, since it's not needed during propagation.

[danno, 2015/02/04 13:42:17]

Done.

                  SimplifiedLowering* lowering) {
+    if (FLAG_turbo_source_positions) {
+      SourcePositionTable::Scope scope(
+          source_positions_, source_positions_->GetSourcePosition(node));
+      VisitNodeDispatch(node, use, lowering);
+    } else {
+      VisitNodeDispatch(node, use, lowering);
+    }
+  }
+
+  // Dispatching routine for visiting the node {node} with the usage {use}.
+  // Depending on the operator, propagate new usage info to the inputs.
+  void VisitNodeDispatch(Node* node, MachineTypeUnion use,
+                         SimplifiedLowering* lowering) {
     switch (node->opcode()) {
       //------------------------------------------------------------------
       // Common operators.
@@ -1071,6 +1087,12 @@ class RepresentationSelector {
   Phase phase_;                     // current phase of algorithm
   RepresentationChanger* changer_;  // for inserting representation changes
   ZoneQueue<Node*> queue_;          // queue for traversing the graph
+  // TODO(danno): RepresentationSelector shouldn't know anything about the
+  // source positions table, but must for now since there currently is no other
+  // way to pass down source position information to nodes created during
+  // lowering. Once this phase becomes a vanilla reducer, it should get source
+  // position information via the SourcePositionWrapper like all other reducers.
+  SourcePositionTable* source_positions_;
   Type* safe_int_additive_range_;
 
   NodeInfo* GetInfo(Node* node) {
@@ -1094,7 +1116,8 @@ Node* SimplifiedLowering::IsTagged(Node* node) {
 void SimplifiedLowering::LowerAllNodes() {
   SimplifiedOperatorBuilder simplified(graph()->zone());
   RepresentationChanger changer(jsgraph(), &simplified, jsgraph()->isolate());
-  RepresentationSelector selector(jsgraph(), zone_, &changer);
+  RepresentationSelector selector(jsgraph(), zone_, &changer,
+                                  source_positions_);
   selector.Run(this);
 }