- Re-apply 52748 and friends with fix. GetConstantStringInfo() returns an empty string for ConstantAggregateZero case which surprises selectiondag.

- Correctly handle memcpy from constant string which is zero-initialized.

llvm-svn: 52891

1 files changed, 1 insertions, 41 deletions

diff --git a/llvm/lib/VMCore/Constants.cpp b/llvm/lib/VMCore/Constants.cpp
index b9976a72070..7a08b5fb8f2 100644
--- a/llvm/lib/VMCore/Constants.cpp
+++ b/llvm/lib/VMCore/Constants.cpp
@@ -2658,44 +2658,4 @@ void ConstantExpr::replaceUsesOfWithOnConstant(Value *From, Value *ToV,
   
   // Delete the old constant!
   destroyConstant();
-}
-
-
-/// getStringValue - Turn an LLVM constant pointer that eventually points to a
-/// global into a string value.  Return an empty string if we can't do it.
-/// Parameter Chop determines if the result is chopped at the first null
-/// terminator.
-///
-std::string Constant::getStringValue(bool Chop, unsigned Offset) {
-  if (GlobalVariable *GV = dyn_cast<GlobalVariable>(this)) {
-    if (GV->hasInitializer() && isa<ConstantArray>(GV->getInitializer())) {
-      ConstantArray *Init = cast<ConstantArray>(GV->getInitializer());
-      if (Init->isString()) {
-        std::string Result = Init->getAsString();
-        if (Offset < Result.size()) {
-          // If we are pointing INTO The string, erase the beginning...
-          Result.erase(Result.begin(), Result.begin()+Offset);
-
-          // Take off the null terminator, and any string fragments after it.
-          if (Chop) {
-            std::string::size_type NullPos = Result.find_first_of((char)0);
-            if (NullPos != std::string::npos)
-              Result.erase(Result.begin()+NullPos, Result.end());
-          }
-          return Result;
-        }
-      }
-    }
-  } else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(this)) {
-    if (CE->getOpcode() == Instruction::GetElementPtr) {
-      // Turn a gep into the specified offset.
-      if (CE->getNumOperands() == 3 &&
-          cast<Constant>(CE->getOperand(1))->isNullValue() &&
-          isa<ConstantInt>(CE->getOperand(2))) {
-        Offset += cast<ConstantInt>(CE->getOperand(2))->getZExtValue();
-        return CE->getOperand(0)->getStringValue(Chop, Offset);
-      }
-    }
-  }
-  return "";
-}
+}
\ No newline at end of file