Revert r108369, sorting llvm.dbg.declare information by source position,

since it doesn't work for front-ends which don't emit column information
(which includes llvm-gcc in its present configuration), and doesn't
work for clang for K&R style variables where the variables are declared
in a different order from the parameter list.

Instead, make a separate pass through the instructions to collect the
llvm.dbg.declare instructions in order. This ensures that the debug
information for variables is emitted in this order.

llvm-svn: 108538

include/llvm/CodeGen/MachineModuleInfo.h

@@ -344,7 +344,7 @@ public:
     VariableDbgInfo.push_back(std::make_pair(N, std::make_pair(Slot, Loc)));
   }
 
-  VariableDbgInfoMapTy &getVariableDbgInfo();
+  VariableDbgInfoMapTy &getVariableDbgInfo() { return VariableDbgInfo; }
 
 }; // End class MachineModuleInfo
 

lib/CodeGen/MachineModuleInfo.cpp

@@ -579,10 +579,3 @@ namespace {
     }
   };
 }
-
-MachineModuleInfo::VariableDbgInfoMapTy &
-MachineModuleInfo::getVariableDbgInfo() {
-  std::stable_sort(VariableDbgInfo.begin(), VariableDbgInfo.end(),
-                   VariableDebugSorter());
-  return VariableDbgInfo;
-}

lib/CodeGen/SelectionDAG/FastISel.cpp

@@ -472,17 +472,7 @@ bool FastISel::SelectCall(const User *I) {
       return true;
     const AllocaInst *AI = dyn_cast<AllocaInst>(Address);
     // Don't handle byval struct arguments or VLAs, for example.
-    // Note that if we have a byval struct argument, fast ISel is turned off;
-    // those are handled in SelectionDAGBuilder.
-    if (AI) {
-      DenseMap<const AllocaInst*, int>::iterator SI =
-        FuncInfo.StaticAllocaMap.find(AI);
-      if (SI == FuncInfo.StaticAllocaMap.end()) break; // VLAs.
-      int FI = SI->second;
-      if (!DI->getDebugLoc().isUnknown())
-        FuncInfo.MF->getMMI().setVariableDbgInfo(DI->getVariable(),
-                                                 FI, DI->getDebugLoc());
-    } else
+    if (!AI)
       // Building the map above is target independent.  Generating DBG_VALUE
       // inline is target dependent; do this now.
       (void)TargetSelectInstruction(cast<Instruction>(I));

lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp

@@ -20,6 +20,7 @@
 #include "llvm/IntrinsicInst.h"
 #include "llvm/LLVMContext.h"
 #include "llvm/Module.h"
+#include "llvm/Analysis/DebugInfo.h"
 #include "llvm/CodeGen/Analysis.h"
 #include "llvm/CodeGen/MachineFunction.h"
 #include "llvm/CodeGen/MachineFrameInfo.h"
@@ -116,12 +117,43 @@ void FunctionLoweringInfo::set(const Function &fn, MachineFunction &mf) {
       }
 
   for (; BB != EB; ++BB)
-    for (BasicBlock::const_iterator I = BB->begin(), E = BB->end(); I != E; ++I)
+    for (BasicBlock::const_iterator I = BB->begin(), E = BB->end(); I != E; ++I) {
+      // Mark values used outside their block as exported, by allocating
+      // a virtual register for them.
       if (isUsedOutsideOfDefiningBlock(I))
         if (!isa<AllocaInst>(I) ||
             !StaticAllocaMap.count(cast<AllocaInst>(I)))
           InitializeRegForValue(I);
 
+      // Collect llvm.dbg.declare information. This is done now instead of
+      // during the initial isel pass through the IR so that it is done
+      // in a predictable order.
+      if (const DbgDeclareInst *DI = dyn_cast<DbgDeclareInst>(I)) {
+        MachineModuleInfo &MMI = MF->getMMI();
+        if (MMI.hasDebugInfo() &&
+            DIVariable(DI->getVariable()).Verify() &&
+            !DI->getDebugLoc().isUnknown()) {
+          // Don't handle byval struct arguments or VLAs, for example.
+          // Non-byval arguments are handled here (they refer to the stack
+          // temporary alloca at this point).
+          const Value *Address = DI->getAddress();
+          if (Address) {
+            if (const BitCastInst *BCI = dyn_cast<BitCastInst>(Address))
+              Address = BCI->getOperand(0);
+            if (const AllocaInst *AI = dyn_cast<AllocaInst>(Address)) {
+              DenseMap<const AllocaInst *, int>::iterator SI =
+                StaticAllocaMap.find(AI);
+              if (SI != StaticAllocaMap.end()) { // Check for VLAs.
+                int FI = SI->second;
+                MMI.setVariableDbgInfo(DI->getVariable(),
+                                       FI, DI->getDebugLoc());
+              }
+            }
+          }
+        }
+      }
+    }
+
   // Create an initial MachineBasicBlock for each LLVM BasicBlock in F.  This
   // also creates the initial PHI MachineInstrs, though none of the input
   // operands are populated.

lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp

@@ -4009,20 +4009,6 @@ SelectionDAGBuilder::visitIntrinsicCall(const CallInst &I, unsigned Intrinsic) {
     if (const BitCastInst *BCI = dyn_cast<BitCastInst>(Address))
       Address = BCI->getOperand(0);
     const AllocaInst *AI = dyn_cast<AllocaInst>(Address);
-    if (AI) {
-      // Don't handle byval arguments or VLAs, for example.
-      // Non-byval arguments are handled here (they refer to the stack temporary
-      // alloca at this point).
-      DenseMap<const AllocaInst*, int>::iterator SI =
-        FuncInfo.StaticAllocaMap.find(AI);
-      if (SI == FuncInfo.StaticAllocaMap.end())
-        return 0; // VLAs.
-      int FI = SI->second;
-
-      MachineModuleInfo &MMI = DAG.getMachineFunction().getMMI();
-      if (!DI.getDebugLoc().isUnknown() && MMI.hasDebugInfo())
-        MMI.setVariableDbgInfo(Variable, FI, DI.getDebugLoc());
-    }
 
     // Build an entry in DbgOrdering.  Debug info input nodes get an SDNodeOrder
     // but do not always have a corresponding SDNode built.  The SDNodeOrder