From: Duncan P. N. Exon Smith <dexonsmith@apple.com>
Date: Fri, 17 Apr 2015 16:33:37 +0000 (+0000)
Subject: AsmPrinter: Stop storing MDLocalVariable in DebugLocEntry
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=f98df953fb9dc50411d9c6582a7f4e830c13845b;p=oota-llvm.git

AsmPrinter: Stop storing MDLocalVariable in DebugLocEntry

Stop storing the `MDLocalVariable` in the `DebugLocEntry::Value`s.  We
generate the list of `DebugLocEntry`s separately for each
variable/inlined-at pair, so the variable never actually changes here.

This is effectively NFC (aside from saving some memory and CPU time).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235202 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/AsmPrinter/DebugLocEntry.h b/lib/CodeGen/AsmPrinter/DebugLocEntry.h
index 8dc003f1820..184fb295784 100644
--- a/lib/CodeGen/AsmPrinter/DebugLocEntry.h
+++ b/lib/CodeGen/AsmPrinter/DebugLocEntry.h
@@ -28,27 +28,23 @@ class DebugLocEntry {
 public:
   /// \brief A single location or constant.
   struct Value {
-    Value(const MDNode *Var, const MDNode *Expr, int64_t i)
-        : Variable(Var), Expression(Expr), EntryKind(E_Integer) {
+    Value(const MDNode *Expr, int64_t i)
+        : Expression(Expr), EntryKind(E_Integer) {
       Constant.Int = i;
     }
-    Value(const MDNode *Var, const MDNode *Expr, const ConstantFP *CFP)
-        : Variable(Var), Expression(Expr), EntryKind(E_ConstantFP) {
+    Value(const MDNode *Expr, const ConstantFP *CFP)
+        : Expression(Expr), EntryKind(E_ConstantFP) {
       Constant.CFP = CFP;
     }
-    Value(const MDNode *Var, const MDNode *Expr, const ConstantInt *CIP)
-        : Variable(Var), Expression(Expr), EntryKind(E_ConstantInt) {
+    Value(const MDNode *Expr, const ConstantInt *CIP)
+        : Expression(Expr), EntryKind(E_ConstantInt) {
       Constant.CIP = CIP;
     }
-    Value(const MDNode *Var, const MDNode *Expr, MachineLocation Loc)
-        : Variable(Var), Expression(Expr), EntryKind(E_Location), Loc(Loc) {
-      assert(isa<MDLocalVariable>(Var));
+    Value(const MDNode *Expr, MachineLocation Loc)
+        : Expression(Expr), EntryKind(E_Location), Loc(Loc) {
       assert(cast<MDExpression>(Expr)->isValid());
     }
 
-    /// The variable to which this location entry corresponds.
-    const MDNode *Variable;
-
     /// Any complex address location expression for this Value.
     const MDNode *Expression;
 
@@ -74,7 +70,6 @@ public:
     const ConstantFP *getConstantFP() const { return Constant.CFP; }
     const ConstantInt *getConstantInt() const { return Constant.CIP; }
     MachineLocation getLoc() const { return Loc; }
-    DIVariable getVariable() const { return cast<MDLocalVariable>(Variable); }
     bool isBitPiece() const { return getExpression()->isBitPiece(); }
     DIExpression getExpression() const {
       return cast_or_null<MDExpression>(Expression);
@@ -103,11 +98,9 @@ public:
   bool MergeValues(const DebugLocEntry &Next) {
     if (Begin == Next.Begin) {
       DIExpression Expr = cast_or_null<MDExpression>(Values[0].Expression);
-      DIVariable Var = cast_or_null<MDLocalVariable>(Values[0].Variable);
       DIExpression NextExpr =
           cast_or_null<MDExpression>(Next.Values[0].Expression);
-      DIVariable NextVar = cast_or_null<MDLocalVariable>(Next.Values[0].Variable);
-      if (Var == NextVar && Expr->isBitPiece() && NextExpr->isBitPiece()) {
+      if (Expr->isBitPiece() && NextExpr->isBitPiece()) {
         addValues(Next.Values);
         End = Next.End;
         return true;
@@ -144,12 +137,12 @@ public:
   // Remove any duplicate entries by dropping all but the first.
   void sortUniqueValues() {
     std::sort(Values.begin(), Values.end());
-    Values.erase(std::unique(Values.begin(), Values.end(),
-                             [](const Value &A, const Value &B) {
-                   return A.getVariable() == B.getVariable() &&
-                          A.getExpression() == B.getExpression();
-                 }),
-                 Values.end());
+    Values.erase(
+        std::unique(
+            Values.begin(), Values.end(), [](const Value &A, const Value &B) {
+              return A.getExpression() == B.getExpression();
+            }),
+        Values.end());
   }
 
   /// \brief Lower this entry into a DWARF expression.
@@ -170,9 +163,6 @@ inline bool operator==(const DebugLocEntry::Value &A,
   if (A.Expression != B.Expression)
     return false;
 
-  if (A.Variable != B.Variable)
-    return false;
-
   switch (A.EntryKind) {
   case DebugLocEntry::Value::E_Location:
     return A.Loc == B.Loc;
diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index 853f6264e93..7c13f1384aa 100644
--- a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -734,7 +734,6 @@ void DwarfDebug::collectVariableInfoFromMMITable(
 // Get .debug_loc entry for the instruction range starting at MI.
 static DebugLocEntry::Value getDebugLocValue(const MachineInstr *MI) {
   const MDNode *Expr = MI->getDebugExpression();
-  const MDNode *Var = MI->getDebugVariable();
 
   assert(MI->getNumOperands() == 4);
   if (MI->getOperand(0).isReg()) {
@@ -745,14 +744,14 @@ static DebugLocEntry::Value getDebugLocValue(const MachineInstr *MI) {
       MLoc.set(MI->getOperand(0).getReg());
     else
       MLoc.set(MI->getOperand(0).getReg(), MI->getOperand(1).getImm());
-    return DebugLocEntry::Value(Var, Expr, MLoc);
+    return DebugLocEntry::Value(Expr, MLoc);
   }
   if (MI->getOperand(0).isImm())
-    return DebugLocEntry::Value(Var, Expr, MI->getOperand(0).getImm());
+    return DebugLocEntry::Value(Expr, MI->getOperand(0).getImm());
   if (MI->getOperand(0).isFPImm())
-    return DebugLocEntry::Value(Var, Expr, MI->getOperand(0).getFPImm());
+    return DebugLocEntry::Value(Expr, MI->getOperand(0).getFPImm());
   if (MI->getOperand(0).isCImm())
-    return DebugLocEntry::Value(Var, Expr, MI->getOperand(0).getCImm());
+    return DebugLocEntry::Value(Expr, MI->getOperand(0).getCImm());
 
   llvm_unreachable("Unexpected 4-operand DBG_VALUE instruction!");
 }
@@ -865,7 +864,6 @@ DwarfDebug::buildLocationList(SmallVectorImpl<DebugLocEntry> &DebugLoc,
     DEBUG({
       dbgs() << CurEntry->getValues().size() << " Values:\n";
       for (auto Value : CurEntry->getValues()) {
-        Value.getVariable()->dump();
         Value.getExpression()->dump();
       }
       dbgs() << "-----\n";