Update LiveDebugVariables after live range splitting.

After a virtual register is split, update any debug user variables that resided
in the old register. This ensures that the LiveDebugVariables are still correct
after register allocation.

This may create DBG_VALUE instructions that place a user variable in a register
in parts of the function and in a stack slot in other parts. DwarfDebug
currently doesn't support that.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130998 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 6 insertions, 1 deletions

diff --git a/lib/CodeGen/LiveRangeEdit.h b/lib/CodeGen/LiveRangeEdit.h
index 14d227e619..db6740c1fb 100644
--- a/lib/CodeGen/LiveRangeEdit.h
+++ b/lib/CodeGen/LiveRangeEdit.h
@@ -18,8 +18,9 @@
 #ifndef LLVM_CODEGEN_LIVERANGEEDIT_H
 #define LLVM_CODEGEN_LIVERANGEEDIT_H
 
-#include "llvm/CodeGen/LiveInterval.h"
+#include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/CodeGen/LiveInterval.h"
 
 namespace llvm {
 
@@ -113,6 +114,10 @@ public:
   bool empty() const { return size() == 0; }
   LiveInterval *get(unsigned idx) const { return newRegs_[idx+firstNew_]; }
 
+  ArrayRef<LiveInterval*> regs() const {
+    return ArrayRef<LiveInterval*>(newRegs_).slice(firstNew_);
+  }
+
   /// FIXME: Temporary accessors until we can get rid of
   /// LiveIntervals::AddIntervalsForSpills
   SmallVectorImpl<LiveInterval*> *getNewVRegs() { return &newRegs_; }