[MLIR] Fixup the LDBG() logging in dataflow/deadcodeanalysis (NFC)

[joker-eph]

This is improving the debug output:

• avoid printing pointers, print ops without regions in general.
• skip extra new-lines in the output
• minor other consistency aspects.

[llvmbot]

@llvm/pr-subscribers-mlir-core

@llvm/pr-subscribers-mlir

Author: Mehdi Amini (joker-eph)

Changes

This is improving the debug output:

• avoid printing pointers, print ops without regions in general.
• skip extra new-lines in the output
• minor other consistency aspects.

---

Full diff: https://github.com/llvm/llvm-project/pull/155085.diff

2 Files Affected:

• (modified) mlir/lib/Analysis/DataFlow/DeadCodeAnalysis.cpp (+35-15)
• (modified) mlir/lib/Analysis/DataFlowFramework.cpp (+5-4)

diff --git a/mlir/lib/Analysis/DataFlow/DeadCodeAnalysis.cpp b/mlir/lib/Analysis/DataFlow/DeadCodeAnalysis.cpp
index 4addff9610e88..b91da5a4c05d3 100644
--- a/mlir/lib/Analysis/DataFlow/DeadCodeAnalysis.cpp
+++ b/mlir/lib/Analysis/DataFlow/DeadCodeAnalysis.cpp
@@ -79,9 +79,17 @@ void Executable::onUpdate(DataFlowSolver *solver) const {
 void PredecessorState::print(raw_ostream &os) const {
   if (allPredecessorsKnown())
     os << "(all) ";
-  os << "predecessors:\n";
-  for (Operation *op : getKnownPredecessors())
-    os << "  " << *op << "\n";
+  os << "predecessors:";
+  if (getKnownPredecessors().empty())
+    os << " (none)";
+  else
+    os << "\n";
+  llvm::interleave(
+      getKnownPredecessors(), os,
+      [&](Operation *op) {
+        os << "  " << OpWithFlags(op, OpPrintingFlags().skipRegions());
+      },
+      "\n");
 }
 
 ChangeResult PredecessorState::join(Operation *predecessor) {
@@ -235,7 +243,8 @@ LogicalResult DeadCodeAnalysis::initializeRecursively(Operation *op) {
   // Initialize the analysis by visiting every op with control-flow semantics.
   if (op->getNumRegions() || op->getNumSuccessors() ||
       isRegionOrCallableReturn(op) || isa<CallOpInterface>(op)) {
-    LDBG() << "[init] Visiting op with control-flow semantics: " << *op;
+    LDBG() << "[init] Visiting op with control-flow semantics: "
+           << OpWithFlags(op, OpPrintingFlags().skipRegions());
     // When the liveness of the parent block changes, make sure to
     // re-invoke the analysis on the op.
     if (op->getBlock())
@@ -247,7 +256,8 @@ LogicalResult DeadCodeAnalysis::initializeRecursively(Operation *op) {
   }
   // Recurse on nested operations.
   for (Region &region : op->getRegions()) {
-    LDBG() << "[init] Recursing into region of op: " << op->getName();
+    LDBG() << "[init] Recursing into region of op: "
+           << OpWithFlags(op, OpPrintingFlags().skipRegions());
     for (Operation &nestedOp : region.getOps()) {
       LDBG() << "[init] Recursing into nested op: "
              << OpWithFlags(&nestedOp, OpPrintingFlags().skipRegions());
@@ -286,19 +296,22 @@ LogicalResult DeadCodeAnalysis::visit(ProgramPoint *point) {
   if (point->isBlockStart())
     return success();
   Operation *op = point->getPrevOp();
-  LDBG() << "Visiting operation: " << *op;
+  LDBG() << "Visiting operation: "
+         << OpWithFlags(op, OpPrintingFlags().skipRegions());
 
   // If the parent block is not executable, there is nothing to do.
   if (op->getBlock() != nullptr &&
       !getOrCreate<Executable>(getProgramPointBefore(op->getBlock()))
            ->isLive()) {
-    LDBG() << "Parent block not live, skipping op: " << *op;
+    LDBG() << "Parent block not live, skipping op: "
+           << OpWithFlags(op, OpPrintingFlags().skipRegions());
     return success();
   }
 
   // We have a live call op. Add this as a live predecessor of the callee.
   if (auto call = dyn_cast<CallOpInterface>(op)) {
-    LDBG() << "Visiting call operation: " << *op;
+    LDBG() << "Visiting call operation: "
+           << OpWithFlags(op, OpPrintingFlags().skipRegions());
     visitCallOperation(call);
   }
 
@@ -306,12 +319,14 @@ LogicalResult DeadCodeAnalysis::visit(ProgramPoint *point) {
   if (op->getNumRegions()) {
     // Check if we can reason about the region control-flow.
     if (auto branch = dyn_cast<RegionBranchOpInterface>(op)) {
-      LDBG() << "Visiting region branch operation: " << *op;
+      LDBG() << "Visiting region branch operation: "
+             << OpWithFlags(op, OpPrintingFlags().skipRegions());
       visitRegionBranchOperation(branch);
 
       // Check if this is a callable operation.
     } else if (auto callable = dyn_cast<CallableOpInterface>(op)) {
-      LDBG() << "Visiting callable operation: " << *op;
+      LDBG() << "Visiting callable operation: "
+             << OpWithFlags(op, OpPrintingFlags().skipRegions());
       const auto *callsites = getOrCreateFor<PredecessorState>(
           getProgramPointAfter(op), getProgramPointAfter(callable));
 
@@ -323,19 +338,22 @@ LogicalResult DeadCodeAnalysis::visit(ProgramPoint *point) {
 
       // Otherwise, conservatively mark all entry blocks as executable.
     } else {
-      LDBG() << "Marking all entry blocks live for op: " << *op;
+      LDBG() << "Marking all entry blocks live for op: "
+             << OpWithFlags(op, OpPrintingFlags().skipRegions());
       markEntryBlocksLive(op);
     }
   }
 
   if (isRegionOrCallableReturn(op)) {
     if (auto branch = dyn_cast<RegionBranchOpInterface>(op->getParentOp())) {
-      LDBG() << "Visiting region terminator: " << *op;
+      LDBG() << "Visiting region terminator: "
+             << OpWithFlags(op, OpPrintingFlags().skipRegions());
       // Visit the exiting terminator of a region.
       visitRegionTerminator(op, branch);
     } else if (auto callable =
                    dyn_cast<CallableOpInterface>(op->getParentOp())) {
-      LDBG() << "Visiting callable terminator: " << *op;
+      LDBG() << "Visiting callable terminator: "
+             << OpWithFlags(op, OpPrintingFlags().skipRegions());
       // Visit the exiting terminator of a callable.
       visitCallableTerminator(op, callable);
     }
@@ -344,12 +362,14 @@ LogicalResult DeadCodeAnalysis::visit(ProgramPoint *point) {
   if (op->getNumSuccessors()) {
     // Check if we can reason about the control-flow.
     if (auto branch = dyn_cast<BranchOpInterface>(op)) {
-      LDBG() << "Visiting branch operation: " << *op;
+      LDBG() << "Visiting branch operation: "
+             << OpWithFlags(op, OpPrintingFlags().skipRegions());
       visitBranchOperation(branch);
 
       // Otherwise, conservatively mark all successors as exectuable.
     } else {
-      LDBG() << "Marking all successors live for op: " << *op;
+      LDBG() << "Marking all successors live for op: "
+             << OpWithFlags(op, OpPrintingFlags().skipRegions());
       for (Block *successor : op->getSuccessors())
         markEdgeLive(op->getBlock(), successor);
     }
diff --git a/mlir/lib/Analysis/DataFlowFramework.cpp b/mlir/lib/Analysis/DataFlowFramework.cpp
index 76bf94aed9e02..7e1b4052027d3 100644
--- a/mlir/lib/Analysis/DataFlowFramework.cpp
+++ b/mlir/lib/Analysis/DataFlowFramework.cpp
@@ -62,11 +62,12 @@ void ProgramPoint::print(raw_ostream &os) const {
     return;
   }
   if (!isBlockStart()) {
-    os << "<after operation>:";
-    return getPrevOp()->print(os, OpPrintingFlags().skipRegions());
+    os << "<after operation>:"
+       << OpWithFlags(getPrevOp(), OpPrintingFlags().skipRegions());
+    return;
   }
-  os << "<before operation>:";
-  return getNextOp()->print(os, OpPrintingFlags().skipRegions());
+  os << "<before operation>:"
+     << OpWithFlags(getNextOp(), OpPrintingFlags().skipRegions());
 }
 
 //===----------------------------------------------------------------------===//