From 948f7d0216cbd847a68fc6aaf391f01816a02494 Mon Sep 17 00:00:00 2001
From: Devang Patel <dpatel@apple.com>
Date: Mon, 25 Oct 2010 20:55:43 +0000
Subject: Add counters to count basic blocks and machine basic blocks with out
 of order line number info. Add counters to count how many basic blocks are
 entirely selected by fastisel.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117310 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp | 67 +++++++++++++++++++++++++--
 1 file changed, 63 insertions(+), 4 deletions(-)

(limited to 'lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp')

diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
index c9589ab..a47f645 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -53,7 +53,13 @@
 using namespace llvm;
 
 STATISTIC(NumFastIselFailures, "Number of instructions fast isel failed on");
+STATISTIC(NumFastIselBlocks, "Number of blocks selected entirely by fast isel");
+STATISTIC(NumDAGBlocks, "Number of blocks selected using DAG");
 STATISTIC(NumDAGIselRetries,"Number of times dag isel has to try another path");
+STATISTIC(NumBBWithOutOfOrderLineInfo, 
+          "Number of blocks with out of order line number info");
+STATISTIC(NumMBBWithOutOfOrderLineInfo, 
+          "Number of machine blocks with out of order line number info");
 
 static cl::opt<bool>
 EnableFastISelVerbose("fast-isel-verbose", cl::Hidden,
@@ -370,7 +376,7 @@ bool SelectionDAGISel::runOnMachineFunction(MachineFunction &mf) {
   return true;
 }
 
-void
+bool
 SelectionDAGISel::SelectBasicBlock(BasicBlock::const_iterator Begin,
                                    BasicBlock::const_iterator End,
                                    bool &HadTailCall) {
@@ -387,6 +393,7 @@ SelectionDAGISel::SelectBasicBlock(BasicBlock::const_iterator Begin,
 
   // Final step, emit the lowered DAG as machine code.
   CodeGenAndEmitDAG();
+  return Begin != End;
 }
 
 void SelectionDAGISel::ComputeLiveOutVRegInfo() {
@@ -726,8 +733,47 @@ bool SelectionDAGISel::TryToFoldFastISelLoad(const LoadInst *LI,
   return FastIS->TryToFoldLoad(&*RI, RI.getOperandNo(), LI);
 }
 
-  
+#ifndef NDEBUG
+/// CheckLineNumbers - Check if basic block instructions follow source order
+/// or not.
+static void CheckLineNumbers(const BasicBlock *BB) {
+  unsigned Line = 0;
+  unsigned Col = 0;
+  for (BasicBlock::const_iterator BI = BB->begin(),
+         BE = BB->end(); BI != BE; ++BI) {
+    const DebugLoc DL = BI->getDebugLoc();
+    if (DL.isUnknown()) continue;
+    unsigned L = DL.getLine();
+    unsigned C = DL.getCol();
+    if (L < Line || (L == Line && C < Col)) {
+      ++NumBBWithOutOfOrderLineInfo;
+      return;
+    }
+    Line = L;
+    Col = C;
+  }
+}  
 
+/// CheckLineNumbers - Check if machine basic block instructions follow source 
+/// order or not.
+static void CheckLineNumbers(const MachineBasicBlock *MBB) {
+  unsigned Line = 0;
+  unsigned Col = 0;
+  for (MachineBasicBlock::const_iterator MBI = MBB->begin(),
+         MBE = MBB->end(); MBI != MBE; ++MBI) {
+    const DebugLoc DL = MBI->getDebugLoc();
+    if (DL.isUnknown()) continue;
+    unsigned L = DL.getLine();
+    unsigned C = DL.getCol();
+    if (L < Line || (L == Line && C < Col)) {
+      ++NumMBBWithOutOfOrderLineInfo;
+      return;
+    }
+    Line = L;
+    Col = C;
+  }
+}  
+#endif
 
 void SelectionDAGISel::SelectAllBasicBlocks(const Function &Fn) {
   // Initialize the Fast-ISel state, if needed.
@@ -737,7 +783,11 @@ void SelectionDAGISel::SelectAllBasicBlocks(const Function &Fn) {
 
   // Iterate over all basic blocks in the function.
   for (Function::const_iterator I = Fn.begin(), E = Fn.end(); I != E; ++I) {
+    bool BBSelectedUsingDAG = false;
     const BasicBlock *LLVMBB = &*I;
+#ifndef NDEBUG
+    CheckLineNumbers(LLVMBB);
+#endif
     FuncInfo->MBB = FuncInfo->MBBMap[LLVMBB];
     FuncInfo->InsertPt = FuncInfo->MBB->getFirstNonPHI();
 
@@ -822,7 +872,7 @@ void SelectionDAGISel::SelectAllBasicBlocks(const Function &Fn) {
           }
 
           bool HadTailCall = false;
-          SelectBasicBlock(Inst, BI, HadTailCall);
+          BBSelectedUsingDAG |= SelectBasicBlock(Inst, BI, HadTailCall);
 
           // If the call was emitted as a tail call, we're done with the block.
           if (HadTailCall) {
@@ -856,13 +906,22 @@ void SelectionDAGISel::SelectAllBasicBlocks(const Function &Fn) {
     // not handled by FastISel. If FastISel is not run, this is the entire
     // block.
     bool HadTailCall;
-    SelectBasicBlock(Begin, BI, HadTailCall);
+    BBSelectedUsingDAG |= SelectBasicBlock(Begin, BI, HadTailCall);
 
     FinishBasicBlock();
     FuncInfo->PHINodesToUpdate.clear();
+    if (BBSelectedUsingDAG)
+      ++NumDAGBlocks;
+    else
+      ++NumFastIselBlocks;
   }
 
   delete FastIS;
+#ifndef NDEBUG
+  for (MachineFunction::const_iterator MBI = MF->begin(), MBE = MF->end();
+       MBI != MBE; ++MBI)
+    CheckLineNumbers(MBI);
+#endif
 }
 
 void
-- 
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