Update prebuilt Clang to r416183b from Android.

https://android.googlesource.com/platform/prebuilts/clang/host/
linux-x86/+/06a71ddac05c22edb2d10b590e1769b3f8619bef

clang 12.0.5 (based on r416183b) from build 7284624.

Change-Id: I277a316abcf47307562d8b748b84870f31a72866
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/linux-x64/clang/include/llvm/Analysis/CFGPrinter.h b/linux-x64/clang/include/llvm/Analysis/CFGPrinter.h
index aaefc11..5370079 100644
--- a/linux-x64/clang/include/llvm/Analysis/CFGPrinter.h
+++ b/linux-x64/clang/include/llvm/Analysis/CFGPrinter.h
@@ -18,49 +18,120 @@
 #ifndef LLVM_ANALYSIS_CFGPRINTER_H
 #define LLVM_ANALYSIS_CFGPRINTER_H
 
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/Analysis/BlockFrequencyInfo.h"
+#include "llvm/Analysis/BranchProbabilityInfo.h"
+#include "llvm/Analysis/HeatUtils.h"
 #include "llvm/IR/CFG.h"
 #include "llvm/IR/Constants.h"
 #include "llvm/IR/Function.h"
 #include "llvm/IR/Instructions.h"
 #include "llvm/IR/PassManager.h"
+#include "llvm/Support/FormatVariadic.h"
 #include "llvm/Support/GraphWriter.h"
 
 namespace llvm {
-class CFGViewerPass
-    : public PassInfoMixin<CFGViewerPass> {
+class CFGViewerPass : public PassInfoMixin<CFGViewerPass> {
 public:
   PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM);
 };
 
-class CFGOnlyViewerPass
-    : public PassInfoMixin<CFGOnlyViewerPass> {
+class CFGOnlyViewerPass : public PassInfoMixin<CFGOnlyViewerPass> {
 public:
   PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM);
 };
 
-class CFGPrinterPass
-    : public PassInfoMixin<CFGPrinterPass> {
+class CFGPrinterPass : public PassInfoMixin<CFGPrinterPass> {
 public:
   PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM);
 };
 
-class CFGOnlyPrinterPass
-    : public PassInfoMixin<CFGOnlyPrinterPass> {
+class CFGOnlyPrinterPass : public PassInfoMixin<CFGOnlyPrinterPass> {
 public:
   PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM);
 };
 
-template<>
-struct DOTGraphTraits<const Function*> : public DefaultDOTGraphTraits {
+class DOTFuncInfo {
+private:
+  const Function *F;
+  const BlockFrequencyInfo *BFI;
+  const BranchProbabilityInfo *BPI;
+  uint64_t MaxFreq;
+  bool ShowHeat;
+  bool EdgeWeights;
+  bool RawWeights;
 
-  DOTGraphTraits (bool isSimple=false) : DefaultDOTGraphTraits(isSimple) {}
+public:
+  DOTFuncInfo(const Function *F) : DOTFuncInfo(F, nullptr, nullptr, 0) {}
 
-  static std::string getGraphName(const Function *F) {
-    return "CFG for '" + F->getName().str() + "' function";
+  DOTFuncInfo(const Function *F, const BlockFrequencyInfo *BFI,
+              const BranchProbabilityInfo *BPI, uint64_t MaxFreq)
+      : F(F), BFI(BFI), BPI(BPI), MaxFreq(MaxFreq) {
+    ShowHeat = false;
+    EdgeWeights = !!BPI; // Print EdgeWeights when BPI is available.
+    RawWeights = !!BFI;  // Print RawWeights when BFI is available.
   }
 
-  static std::string getSimpleNodeLabel(const BasicBlock *Node,
-                                        const Function *) {
+  const BlockFrequencyInfo *getBFI() { return BFI; }
+
+  const BranchProbabilityInfo *getBPI() { return BPI; }
+
+  const Function *getFunction() { return this->F; }
+
+  uint64_t getMaxFreq() { return MaxFreq; }
+
+  uint64_t getFreq(const BasicBlock *BB) {
+    return BFI->getBlockFreq(BB).getFrequency();
+  }
+
+  void setHeatColors(bool ShowHeat) { this->ShowHeat = ShowHeat; }
+
+  bool showHeatColors() { return ShowHeat; }
+
+  void setRawEdgeWeights(bool RawWeights) { this->RawWeights = RawWeights; }
+
+  bool useRawEdgeWeights() { return RawWeights; }
+
+  void setEdgeWeights(bool EdgeWeights) { this->EdgeWeights = EdgeWeights; }
+
+  bool showEdgeWeights() { return EdgeWeights; }
+};
+
+template <>
+struct GraphTraits<DOTFuncInfo *> : public GraphTraits<const BasicBlock *> {
+  static NodeRef getEntryNode(DOTFuncInfo *CFGInfo) {
+    return &(CFGInfo->getFunction()->getEntryBlock());
+  }
+
+  // nodes_iterator/begin/end - Allow iteration over all nodes in the graph
+  using nodes_iterator = pointer_iterator<Function::const_iterator>;
+
+  static nodes_iterator nodes_begin(DOTFuncInfo *CFGInfo) {
+    return nodes_iterator(CFGInfo->getFunction()->begin());
+  }
+
+  static nodes_iterator nodes_end(DOTFuncInfo *CFGInfo) {
+    return nodes_iterator(CFGInfo->getFunction()->end());
+  }
+
+  static size_t size(DOTFuncInfo *CFGInfo) {
+    return CFGInfo->getFunction()->size();
+  }
+};
+
+template <>
+struct DOTGraphTraits<DOTFuncInfo *> : public DefaultDOTGraphTraits {
+
+  // Cache for is hidden property
+  llvm::DenseMap<const BasicBlock *, bool> isHiddenBasicBlock;
+
+  DOTGraphTraits(bool isSimple = false) : DefaultDOTGraphTraits(isSimple) {}
+
+  static std::string getGraphName(DOTFuncInfo *CFGInfo) {
+    return "CFG for '" + CFGInfo->getFunction()->getName().str() + "' function";
+  }
+
+  static std::string getSimpleNodeLabel(const BasicBlock *Node, DOTFuncInfo *) {
     if (!Node->getName().empty())
       return Node->getName().str();
 
@@ -71,8 +142,18 @@
     return OS.str();
   }
 
-  static std::string getCompleteNodeLabel(const BasicBlock *Node,
-                                          const Function *) {
+  static void eraseComment(std::string &OutStr, unsigned &I, unsigned Idx) {
+    OutStr.erase(OutStr.begin() + I, OutStr.begin() + Idx);
+    --I;
+  }
+
+  static std::string getCompleteNodeLabel(
+      const BasicBlock *Node, DOTFuncInfo *,
+      llvm::function_ref<void(raw_string_ostream &, const BasicBlock &)>
+          HandleBasicBlock = [](raw_string_ostream &OS,
+                                const BasicBlock &Node) -> void { OS << Node; },
+      llvm::function_ref<void(std::string &, unsigned &, unsigned)>
+          HandleComment = eraseComment) {
     enum { MaxColumns = 80 };
     std::string Str;
     raw_string_ostream OS(Str);
@@ -82,24 +163,24 @@
       OS << ":";
     }
 
-    OS << *Node;
+    HandleBasicBlock(OS, *Node);
     std::string OutStr = OS.str();
-    if (OutStr[0] == '\n') OutStr.erase(OutStr.begin());
+    if (OutStr[0] == '\n')
+      OutStr.erase(OutStr.begin());
 
     // Process string output to make it nicer...
     unsigned ColNum = 0;
     unsigned LastSpace = 0;
     for (unsigned i = 0; i != OutStr.length(); ++i) {
-      if (OutStr[i] == '\n') {                            // Left justify
+      if (OutStr[i] == '\n') { // Left justify
         OutStr[i] = '\\';
-        OutStr.insert(OutStr.begin()+i+1, 'l');
+        OutStr.insert(OutStr.begin() + i + 1, 'l');
         ColNum = 0;
         LastSpace = 0;
-      } else if (OutStr[i] == ';') {                      // Delete comments!
-        unsigned Idx = OutStr.find('\n', i+1);            // Find end of line
-        OutStr.erase(OutStr.begin()+i, OutStr.begin()+Idx);
-        --i;
-      } else if (ColNum == MaxColumns) {                  // Wrap lines.
+      } else if (OutStr[i] == ';') {             // Delete comments!
+        unsigned Idx = OutStr.find('\n', i + 1); // Find end of line
+        HandleComment(OutStr, i, Idx);
+      } else if (ColNum == MaxColumns) { // Wrap lines.
         // Wrap very long names even though we can't find a space.
         if (!LastSpace)
           LastSpace = i;
@@ -107,8 +188,7 @@
         ColNum = i - LastSpace;
         LastSpace = 0;
         i += 3; // The loop will advance 'i' again.
-      }
-      else
+      } else
         ++ColNum;
       if (OutStr[i] == ' ')
         LastSpace = i;
@@ -116,16 +196,16 @@
     return OutStr;
   }
 
-  std::string getNodeLabel(const BasicBlock *Node,
-                           const Function *Graph) {
+  std::string getNodeLabel(const BasicBlock *Node, DOTFuncInfo *CFGInfo) {
+
     if (isSimple())
-      return getSimpleNodeLabel(Node, Graph);
+      return getSimpleNodeLabel(Node, CFGInfo);
     else
-      return getCompleteNodeLabel(Node, Graph);
+      return getCompleteNodeLabel(Node, CFGInfo);
   }
 
   static std::string getEdgeSourceLabel(const BasicBlock *Node,
-                                        succ_const_iterator I) {
+                                        const_succ_iterator I) {
     // Label source of conditional branches with "T" or "F"
     if (const BranchInst *BI = dyn_cast<BranchInst>(Node->getTerminator()))
       if (BI->isConditional())
@@ -135,7 +215,8 @@
     if (const SwitchInst *SI = dyn_cast<SwitchInst>(Node->getTerminator())) {
       unsigned SuccNo = I.getSuccessorIndex();
 
-      if (SuccNo == 0) return "def";
+      if (SuccNo == 0)
+        return "def";
 
       std::string Str;
       raw_string_ostream OS(Str);
@@ -147,12 +228,39 @@
   }
 
   /// Display the raw branch weights from PGO.
-  std::string getEdgeAttributes(const BasicBlock *Node, succ_const_iterator I,
-                                const Function *F) {
+  std::string getEdgeAttributes(const BasicBlock *Node, const_succ_iterator I,
+                                DOTFuncInfo *CFGInfo) {
+    if (!CFGInfo->showEdgeWeights())
+      return "";
+
     const Instruction *TI = Node->getTerminator();
     if (TI->getNumSuccessors() == 1)
+      return "penwidth=2";
+
+    unsigned OpNo = I.getSuccessorIndex();
+
+    if (OpNo >= TI->getNumSuccessors())
       return "";
 
+    BasicBlock *SuccBB = TI->getSuccessor(OpNo);
+    auto BranchProb = CFGInfo->getBPI()->getEdgeProbability(Node, SuccBB);
+    double WeightPercent = ((double)BranchProb.getNumerator()) /
+                           ((double)BranchProb.getDenominator());
+    double Width = 1 + WeightPercent;
+
+    if (!CFGInfo->useRawEdgeWeights())
+      return formatv("label=\"{0:P}\" penwidth={1}", WeightPercent, Width)
+          .str();
+
+    // Prepend a 'W' to indicate that this is a weight rather than the actual
+    // profile count (due to scaling).
+
+    uint64_t Freq = CFGInfo->getFreq(Node);
+    std::string Attrs = formatv("label=\"W:{0}\" penwidth={1}",
+                                (uint64_t)(Freq * WeightPercent), Width);
+    if (Attrs.size())
+      return Attrs;
+
     MDNode *WeightsNode = TI->getMetadata(LLVMContext::MD_prof);
     if (!WeightsNode)
       return "";
@@ -161,25 +269,41 @@
     if (MDName->getString() != "branch_weights")
       return "";
 
-    unsigned OpNo = I.getSuccessorIndex() + 1;
+    OpNo = I.getSuccessorIndex() + 1;
     if (OpNo >= WeightsNode->getNumOperands())
       return "";
     ConstantInt *Weight =
         mdconst::dyn_extract<ConstantInt>(WeightsNode->getOperand(OpNo));
     if (!Weight)
       return "";
-
-    // Prepend a 'W' to indicate that this is a weight rather than the actual
-    // profile count (due to scaling).
-    return ("label=\"W:" + Twine(Weight->getZExtValue()) + "\"").str();
+    return ("label=\"W:" + std::to_string(Weight->getZExtValue()) +
+            "\" penwidth=" + std::to_string(Width));
   }
+
+  std::string getNodeAttributes(const BasicBlock *Node, DOTFuncInfo *CFGInfo) {
+
+    if (!CFGInfo->showHeatColors())
+      return "";
+
+    uint64_t Freq = CFGInfo->getFreq(Node);
+    std::string Color = getHeatColor(Freq, CFGInfo->getMaxFreq());
+    std::string EdgeColor = (Freq <= (CFGInfo->getMaxFreq() / 2))
+                                ? (getHeatColor(0))
+                                : (getHeatColor(1));
+
+    std::string Attrs = "color=\"" + EdgeColor + "ff\", style=filled," +
+                        " fillcolor=\"" + Color + "70\"";
+    return Attrs;
+  }
+  bool isNodeHidden(const BasicBlock *Node, const DOTFuncInfo *CFGInfo);
+  void computeHiddenNodes(const Function *F);
 };
 } // End llvm namespace
 
 namespace llvm {
-  class FunctionPass;
-  FunctionPass *createCFGPrinterLegacyPassPass ();
-  FunctionPass *createCFGOnlyPrinterLegacyPassPass ();
+class FunctionPass;
+FunctionPass *createCFGPrinterLegacyPassPass();
+FunctionPass *createCFGOnlyPrinterLegacyPassPass();
 } // End llvm namespace
 
 #endif