[llvm-commits] [llvm] r90632 - /llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp

[Dan Gohman]

Author: djg
Date: Fri Dec  4 18:27:08 2009
New Revision: 90632

URL: http://llvm.org/viewvc/llvm-project?rev=90632&view=rev
Log:
The debug information for an LLVM Instruction applies to that Instruction
and that Instruction only. Implement this by setting the "current debug position"
back to Unknown after processing each instruction.

Modified:
    llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp?rev=90632&r1=90631&r2=90632&view=diff

==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp Fri Dec  4 18:27:08 2009
@@ -362,6 +362,39 @@
   return true;
 }
 
+/// SetDebugLoc - Update MF's and SDB's DebugLocs if debug information is
+/// attached with this instruction.
+static void SetDebugLoc(unsigned MDDbgKind,
+                        MetadataContext &TheMetadata,
+                        Instruction *I,
+                        SelectionDAGBuilder *SDB,
+                        FastISel *FastIS,
+                        MachineFunction *MF) {
+  if (!isa<DbgInfoIntrinsic>(I)) 
+    if (MDNode *Dbg = TheMetadata.getMD(MDDbgKind, I)) {
+      DILocation DILoc(Dbg);
+      DebugLoc Loc = ExtractDebugLocation(DILoc, MF->getDebugLocInfo());
+
+      SDB->setCurDebugLoc(Loc);
+
+      if (FastIS)
+        FastIS->setCurDebugLoc(Loc);
+
+      // If the function doesn't have a default debug location yet, set
+      // it. This is kind of a hack.
+      if (MF->getDefaultDebugLoc().isUnknown())
+        MF->setDefaultDebugLoc(Loc);
+    }
+}
+
+/// ResetDebugLoc - Set MF's and SDB's DebugLocs to Unknown.
+static void ResetDebugLoc(SelectionDAGBuilder *SDB,
+                          FastISel *FastIS) {
+  SDB->setCurDebugLoc(DebugLoc::getUnknownLoc());
+  if (FastIS)
+    SDB->setCurDebugLoc(DebugLoc::getUnknownLoc());
+}
+
 void SelectionDAGISel::SelectBasicBlock(BasicBlock *LLVMBB,
                                         BasicBlock::iterator Begin,
                                         BasicBlock::iterator End,
@@ -373,20 +406,16 @@
   // Lower all of the non-terminator instructions. If a call is emitted
   // as a tail call, cease emitting nodes for this block.
   for (BasicBlock::iterator I = Begin; I != End && !SDB->HasTailCall; ++I) {
-    if (MDDbgKind) {
-      // Update DebugLoc if debug information is attached with this
-      // instruction.
-      if (!isa<DbgInfoIntrinsic>(I)) 
-        if (MDNode *Dbg = TheMetadata.getMD(MDDbgKind, I)) {
-          DILocation DILoc(Dbg);
-          DebugLoc Loc = ExtractDebugLocation(DILoc, MF->getDebugLocInfo());
-          SDB->setCurDebugLoc(Loc);
-          if (MF->getDefaultDebugLoc().isUnknown())
-            MF->setDefaultDebugLoc(Loc);
-        }
-    }
-    if (!isa<TerminatorInst>(I))
+    if (MDDbgKind)
+      SetDebugLoc(MDDbgKind, TheMetadata, I, SDB, 0, MF);
+
+    if (!isa<TerminatorInst>(I)) {
       SDB->visit(*I);
+
+      // Set the current debug location back to "unknown" so that it doesn't
+      // spuriously apply to subsequent instructions.
+      ResetDebugLoc(SDB, 0);
+    }
   }
 
   if (!SDB->HasTailCall) {
@@ -401,7 +430,9 @@
       HandlePHINodesInSuccessorBlocks(LLVMBB);
 
       // Lower the terminator after the copies are emitted.
+      SetDebugLoc(MDDbgKind, TheMetadata, LLVMBB->getTerminator(), SDB, 0, MF);
       SDB->visit(*LLVMBB->getTerminator());
+      ResetDebugLoc(SDB, 0);
     }
   }
 
@@ -738,24 +769,14 @@
       FastIS->startNewBlock(BB);
       // Do FastISel on as many instructions as possible.
       for (; BI != End; ++BI) {
-        if (MDDbgKind) {
-          // Update DebugLoc if debug information is attached with this
-          // instruction.
-          if (!isa<DbgInfoIntrinsic>(BI)) 
-            if (MDNode *Dbg = TheMetadata.getMD(MDDbgKind, BI)) {
-              DILocation DILoc(Dbg);
-              DebugLoc Loc = ExtractDebugLocation(DILoc,
-                                                  MF.getDebugLocInfo());
-              FastIS->setCurDebugLoc(Loc);
-              if (MF.getDefaultDebugLoc().isUnknown())
-                MF.setDefaultDebugLoc(Loc);
-            }
-        }
+        if (MDDbgKind)
+          SetDebugLoc(MDDbgKind, TheMetadata, BI, SDB, FastIS, &MF);
 
         // Just before the terminator instruction, insert instructions to
         // feed PHI nodes in successor blocks.
         if (isa<TerminatorInst>(BI))
           if (!HandlePHINodesInSuccessorBlocksFast(LLVMBB, FastIS)) {
+            ResetDebugLoc(SDB, FastIS);
             if (EnableFastISelVerbose || EnableFastISelAbort) {
               errs() << "FastISel miss: ";
               BI->dump();
@@ -766,12 +787,20 @@
           }
 
         // First try normal tablegen-generated "fast" selection.
-        if (FastIS->SelectInstruction(BI))
+        if (FastIS->SelectInstruction(BI)) {
+          ResetDebugLoc(SDB, FastIS);
           continue;
+        }
 
         // Next, try calling the target to attempt to handle the instruction.
-        if (FastIS->TargetSelectInstruction(BI))
+        if (FastIS->TargetSelectInstruction(BI)) {
+          ResetDebugLoc(SDB, FastIS);
           continue;
+        }
+
+        // Clear out the debug location so that it doesn't carry over to
+        // unrelated instructions.
+        ResetDebugLoc(SDB, FastIS);
 
         // Then handle certain instructions as single-LLVM-Instruction blocks.
         if (isa<CallInst>(BI)) {
@@ -786,8 +815,6 @@
               R = FuncInfo->CreateRegForValue(BI);
           }
 
-          SDB->setCurDebugLoc(FastIS->getCurDebugLoc());
-
           bool HadTailCall = false;
           SelectBasicBlock(LLVMBB, BI, llvm::next(BI), HadTailCall);
 
@@ -823,9 +850,6 @@
     // not handled by FastISel. If FastISel is not run, this is the entire
     // block.
     if (BI != End) {
-      // If FastISel is run and it has known DebugLoc then use it.
-      if (FastIS && !FastIS->getCurDebugLoc().isUnknown())
-        SDB->setCurDebugLoc(FastIS->getCurDebugLoc());
       bool HadTailCall;
       SelectBasicBlock(LLVMBB, BI, End, HadTailCall);
     }