Keep track of incoming argument's location while emitting LiveIns.

[oota-llvm.git] / lib / CodeGen / SelectionDAG / SelectionDAGISel.cpp

diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
index 6a999c2dc9f4ffef3b5741030c19845bc2d56c28..62ebc81ef86e21ea009a726eb38adbca38e4b08a 100644 (file)
--- a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -771,8 +771,16 @@ bool SelectionDAGISel::TryToFoldFastISelLoad(const LoadInst *LI,
   assert(RI.getOperand().isUse() &&
          "The only use of the vreg must be a use, we haven't emitted the def!");
 
+  MachineInstr *User = &*RI;
+  
+  // Set the insertion point properly.  Folding the load can cause generation of
+  // other random instructions (like sign extends) for addressing modes, make
+  // sure they get inserted in a logical place before the new instruction.
+  FuncInfo->InsertPt = User;
+  FuncInfo->MBB = User->getParent();
+
   // Ask the target to try folding the load.
-  return FastIS->TryToFoldLoad(&*RI, RI.getOperandNo(), LI);
+  return FastIS->TryToFoldLoad(User, RI.getOperandNo(), LI);
 }
 
 #ifndef NDEBUG
@@ -843,8 +851,17 @@ void SelectionDAGISel::SelectAllBasicBlocks(const Function &Fn) {
       PrepareEHLandingPad();
 
     // Lower any arguments needed in this block if this is the entry block.
-    if (LLVMBB == &Fn.getEntryBlock())
+    if (LLVMBB == &Fn.getEntryBlock()) {
+      for (BasicBlock::const_iterator DBI = LLVMBB->begin(), DBE = LLVMBB->end();
+           DBI != DBE; ++DBI) {
+        if (const DbgInfoIntrinsic *DI = dyn_cast<DbgInfoIntrinsic>(DBI)) {
+          const DebugLoc DL = DI->getDebugLoc();
+          SDB->setCurDebugLoc(DL);
+          break;
+        }
+      }
       LowerArguments(LLVMBB);
+    }
 
     // Before doing SelectionDAG ISel, see if FastISel has been requested.
     if (FastIS) {
@@ -890,11 +907,9 @@ void SelectionDAGISel::SelectAllBasicBlocks(const Function &Fn) {
           if (Inst != Begin)
             BeforeInst = llvm::prior(llvm::prior(BI));
           if (BeforeInst && isa<LoadInst>(BeforeInst) &&
-              BeforeInst->hasOneUse() && *BeforeInst->use_begin() == Inst) {
-            FastIS->recomputeInsertPt();
-            if (TryToFoldFastISelLoad(cast<LoadInst>(BeforeInst), FastIS))
-              --BI; // If we succeeded, don't re-select the load.
-          }
+              BeforeInst->hasOneUse() && *BeforeInst->use_begin() == Inst &&
+              TryToFoldFastISelLoad(cast<LoadInst>(BeforeInst), FastIS))
+            --BI; // If we succeeded, don't re-select the load.
           continue;
         }
 
@@ -1135,7 +1150,7 @@ SelectionDAGISel::FinishBasicBlock() {
   // additional DAGs necessary.
   for (unsigned i = 0, e = SDB->SwitchCases.size(); i != e; ++i) {
     // Set the current basic block to the mbb we wish to insert the code into
-    MachineBasicBlock *ThisBB = FuncInfo->MBB = SDB->SwitchCases[i].ThisBB;
+    FuncInfo->MBB = SDB->SwitchCases[i].ThisBB;
     FuncInfo->InsertPt = FuncInfo->MBB->end();
 
     // Determine the unique successors.
@@ -1144,13 +1159,15 @@ SelectionDAGISel::FinishBasicBlock() {
     if (SDB->SwitchCases[i].TrueBB != SDB->SwitchCases[i].FalseBB)
       Succs.push_back(SDB->SwitchCases[i].FalseBB);
 
-    // Emit the code. Note that this could result in ThisBB being split, so
-    // we need to check for updates.
+    // Emit the code. Note that this could result in FuncInfo->MBB being split.
     SDB->visitSwitchCase(SDB->SwitchCases[i], FuncInfo->MBB);
     CurDAG->setRoot(SDB->getRoot());
     SDB->clear();
     CodeGenAndEmitDAG();
-    ThisBB = FuncInfo->MBB;
+
+    // Remember the last block, now that any splitting is done, for use in
+    // populating PHI nodes in successors.
+    MachineBasicBlock *ThisBB = FuncInfo->MBB;
 
     // Handle any PHI nodes in successors of this chunk, as if we were coming
     // from the original BB before switch expansion.  Note that PHI nodes can