From 4147f39769d404cab02da4beea852ad2600dadbb Mon Sep 17 00:00:00 2001
From: Chandler Carruth <chandlerc@gmail.com>
Date: Fri, 5 Aug 2011 00:51:31 +0000
Subject: [PATCH] Temporarily revert r135528 which distinguishes between two
 copies of one inlined variable, based on the discussion in PR10542.

This explodes the runtime of several passes down the pipeline due to
a large number of "copies" remaining live across a large function. This
only shows up with both debug and opt, but when it does it creates
a many-minute compile when self-hosting LLVM+Clang. There are several
other cases that show these types of regressions.

All of this is tracked in PR10542, and progress is being made on fixing
the issue. Once its addressed, the re-instated, but until then this
restores the performance for self-hosting and other opt+debug builds.

Devang, let me know if this causes any trouble, or impedes fixing it in
any way, and thanks for working on this!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@136953 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/llvm/Analysis/DebugInfo.h       |  3 ---
 lib/Analysis/DebugInfo.cpp              | 11 -----------
 lib/CodeGen/AsmPrinter/DwarfDebug.cpp   |  8 ++------
 lib/Transforms/Utils/InlineFunction.cpp |  9 +--------
 4 files changed, 3 insertions(+), 28 deletions(-)

diff --git a/include/llvm/Analysis/DebugInfo.h b/include/llvm/Analysis/DebugInfo.h
index 929dd1d13a7..88372b27999 100644
--- a/include/llvm/Analysis/DebugInfo.h
+++ b/include/llvm/Analysis/DebugInfo.h
@@ -727,9 +727,6 @@ namespace llvm {
   DIVariable createInlinedVariable(MDNode *DV, MDNode *InlinedScope,
                                    LLVMContext &VMContext);
 
-  /// cleanseInlinedVariable - Remove inlined scope from the variable.
-  DIVariable cleanseInlinedVariable(MDNode *DV, LLVMContext &VMContext);
-
   class DebugInfoFinder {
   public:
     /// processModule - Process entire module and collect debug info
diff --git a/lib/Analysis/DebugInfo.cpp b/lib/Analysis/DebugInfo.cpp
index dd85a4fcc80..43408eea698 100644
--- a/lib/Analysis/DebugInfo.cpp
+++ b/lib/Analysis/DebugInfo.cpp
@@ -782,17 +782,6 @@ DIVariable llvm::createInlinedVariable(MDNode *DV, MDNode *InlinedScope,
   return DIVariable(MDNode::get(VMContext, Elts));
 }
 
-/// cleanseInlinedVariable - Remove inlined scope from the variable.
-DIVariable llvm::cleanseInlinedVariable(MDNode *DV, LLVMContext &VMContext) {
-  SmallVector<Value *, 16> Elts;
-  // Insert inlined scope as 7th element.
-  for (unsigned i = 0, e = DV->getNumOperands(); i != e; ++i)
-    i == 7 ? 
-      Elts.push_back(llvm::Constant::getNullValue(Type::getInt32Ty(VMContext))):
-      Elts.push_back(DV->getOperand(i));
-  return DIVariable(MDNode::get(VMContext, Elts));
-}
-
 //===----------------------------------------------------------------------===//
 // DebugInfoFinder implementations.
 //===----------------------------------------------------------------------===//
diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index 4900e943104..0a3f75037b1 100644
--- a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -1286,18 +1286,14 @@ void DwarfDebug::endModule() {
 }
 
 /// findAbstractVariable - Find abstract variable, if any, associated with Var.
-DbgVariable *DwarfDebug::findAbstractVariable(DIVariable &DV,
+DbgVariable *DwarfDebug::findAbstractVariable(DIVariable &Var,
                                               DebugLoc ScopeLoc) {
-  LLVMContext &Ctx = DV->getContext();
-
-  // More then one inlined variable corresponds to one abstract variable.
-  DIVariable Var = cleanseInlinedVariable(DV, Ctx);
 
   DbgVariable *AbsDbgVariable = AbstractVariables.lookup(Var);
   if (AbsDbgVariable)
     return AbsDbgVariable;
 
-
+  LLVMContext &Ctx = Var->getContext();
   DbgScope *Scope = AbstractScopes.lookup(ScopeLoc.getScope(Ctx));
   if (!Scope)
     return NULL;
diff --git a/lib/Transforms/Utils/InlineFunction.cpp b/lib/Transforms/Utils/InlineFunction.cpp
index 714b12c7d29..6d8a319635c 100644
--- a/lib/Transforms/Utils/InlineFunction.cpp
+++ b/lib/Transforms/Utils/InlineFunction.cpp
@@ -770,15 +770,8 @@ static void fixupLineNumbers(Function *Fn, Function::iterator FI,
     for (BasicBlock::iterator BI = FI->begin(), BE = FI->end();
          BI != BE; ++BI) {
       DebugLoc DL = BI->getDebugLoc();
-      if (!DL.isUnknown()) {
+      if (!DL.isUnknown())
         BI->setDebugLoc(updateInlinedAtInfo(DL, TheCallDL, BI->getContext()));
-        if (DbgValueInst *DVI = dyn_cast<DbgValueInst>(BI)) {
-          LLVMContext &Ctx = BI->getContext();
-          MDNode *InlinedAt = BI->getDebugLoc().getInlinedAt(Ctx);
-          DVI->setOperand(2, createInlinedVariable(DVI->getVariable(), 
-                                                   InlinedAt, Ctx));
-        }
-      }
     }
   }
 }