This reapplies r207130 with an additional testcase+and a missing check for

[opencl/llvm.git] / lib / CodeGen / CodeGenPrepare.cpp

diff --git a/lib/CodeGen/CodeGenPrepare.cpp b/lib/CodeGen/CodeGenPrepare.cpp
index 85734f715c9a170359648845b91af64312334219..875615c4c3e3584d4efed44aa8801fd522a24d27 100644 (file)
--- a/lib/CodeGen/CodeGenPrepare.cpp
+++ b/lib/CodeGen/CodeGenPrepare.cpp
@@ -3470,7 +3470,12 @@ bool CodeGenPrepare::PlaceDbgValues(Function &F) {
     for (BasicBlock::iterator BI = I->begin(), BE = I->end(); BI != BE;) {
       Instruction *Insn = BI; ++BI;
       DbgValueInst *DVI = dyn_cast<DbgValueInst>(Insn);
-      if (!DVI) {
+      // Leave dbg.values that refer to an alloca alone. These
+      // instrinsics describe the address of a variable (= the alloca)
+      // being taken.  They should not be moved next to the alloca
+      // (and to the beginning of the scope), but rather stay close to
+      // where said address is used.
+      if (!DVI || (DVI->getValue() && isa<AllocaInst>(DVI->getValue()))) {
         PrevNonDbgInst = Insn;
         continue;
       }