Remove obsolete DEBUG only instance variable BasicBlock::bbLoopNum (#…

…34652)

* Remove obsolete DEBUG only instance variable BasicBlock::bbLoopNum

Comment at declaration in block.h

    // This is the label a loop gets as part of the second, reachability-based
    // loop discovery mechanism.  This is apparently only used for debugging.
    // We hope we'll eventually just have one loop-discovery mechanism, and this will go away.
    INDEBUG(loopNumber bbLoopNum;) // set to 'n' for a loop #n header

* Run jit-format

src/coreclr/src/jit/block.cpp

@@ -636,7 +636,6 @@ bool BasicBlock::CloneBlockState(
  VarSetOps::AssignAllowUninitRhs(compiler, to->bbScope, from->bbScope);
  to->bbNatLoopNum = from->bbNatLoopNum;
 #ifdef DEBUG
- to->bbLoopNum = from->bbLoopNum;
  to->bbTgtStkDepth = from->bbTgtStkDepth;
 #endif // DEBUG
 

src/coreclr/src/jit/block.h

@@ -847,11 +847,6 @@ struct BasicBlock : private LIR::Range
  typedef unsigned char loopNumber;
  static const unsigned NOT_IN_LOOP = UCHAR_MAX;
 
- // This is the label a loop gets as part of the second, reachability-based
- // loop discovery mechanism. This is apparently only used for debugging.
- // We hope we'll eventually just have one loop-discovery mechanism, and this will go away.
- INDEBUG(loopNumber bbLoopNum;) // set to 'n' for a loop #n header
-
  loopNumber bbNatLoopNum; // Index, in optLoopTable, of most-nested loop that contains this block,
  // or else NOT_IN_LOOP if this block is not in a loop.
 

src/coreclr/src/jit/optimizer.cpp

@@ -146,16 +146,16 @@ void Compiler::optMarkLoopBlocks(BasicBlock* begBlk, BasicBlock* endBlk, bool ex
  noway_assert(begBlk->bbNum <= endBlk->bbNum);
  noway_assert(begBlk->isLoopHead());
  noway_assert(fgReachable(begBlk, endBlk));
+ noway_assert(!opts.MinOpts());
 
 #ifdef DEBUG
  if (verbose)
  {
- printf("\nMarking loop L%02u", begBlk->bbLoopNum);
+ printf("\nMarking a loop from " FMT_BB " to " FMT_BB, begBlk->bbNum,
+ excludeEndBlk ? endBlk->bbPrev->bbNum : endBlk->bbNum);
  }
 #endif
 
- noway_assert(!opts.MinOpts());
-
  /* Build list of backedges for block begBlk */
  flowList* backedgeList = nullptr;
 
@@ -327,11 +327,11 @@ void Compiler::optUnmarkLoopBlocks(BasicBlock* begBlk, BasicBlock* endBlk)
  {
  if (backEdgeCount > 0)
  {
- printf("\nNot removing loop L%02u, due to an additional back edge", begBlk->bbLoopNum);
+ printf("\nNot removing loop at " FMT_BB ", due to an additional back edge", begBlk->bbNum);
  }
  else if (backEdgeCount == 0)
  {
- printf("\nNot removing loop L%02u, due to no back edge", begBlk->bbLoopNum);
+ printf("\nNot removing loop at " FMT_BB ", due to no back edge", begBlk->bbNum);
  }
  }
 #endif
@@ -343,7 +343,7 @@ void Compiler::optUnmarkLoopBlocks(BasicBlock* begBlk, BasicBlock* endBlk)
 #ifdef DEBUG
  if (verbose)
  {
- printf("\nUnmarking loop L%02u", begBlk->bbLoopNum);
+ printf("\nUnmarking loop at " FMT_BB, begBlk->bbNum);
  }
 #endif
 
@@ -651,14 +651,6 @@ void Compiler::optPrintLoopInfo(unsigned loopInd,
 {
  noway_assert(lpHead);
 
- //
- // NOTE: we take "loopInd" as an argument instead of using the one
- // stored in begBlk->bbLoopNum because sometimes begBlk->bbLoopNum
- // has not be set correctly. For example, in optRecordLoop().
- // However, in most of the cases, loops should have been recorded.
- // Therefore the correct way is to call the Compiler::optPrintLoopInfo(unsigned lnum)
- // version of this method.
- //
  printf("L%02u, from " FMT_BB, loopInd, lpFirst->bbNum);
  if (lpTop != lpFirst)
  {
@@ -4371,8 +4363,6 @@ void Compiler::optOptimizeLayout()
  continue;
  }
 
- assert(block->bbLoopNum == 0);
-
  if (compCodeOpt() != SMALL_CODE)
  {
  /* Optimize "while(cond){}" loops to "cond; do{}while(cond);" */
@@ -4480,11 +4470,6 @@ void Compiler::optOptimizeLoops()
  if (foundBottom)
  {
  loopNum++;
-#ifdef DEBUG
- /* Mark the loop header as such */
- assert(FitsIn<unsigned char>(loopNum));
- top->bbLoopNum = (unsigned char)loopNum;
-#endif
 
  /* Mark all blocks between 'top' and 'bottom' */