isDereferenceablePointer: look through gc.relocate calls
While a theoretical GC might change dereferenceability on collection,
there is no such known collector and no need to account for the case
with a flag yet.
Differential Revision: http://reviews.llvm.org/D7454
llvm-svn: 228606
diff --git a/llvm/lib/IR/Value.cpp b/llvm/lib/IR/Value.cpp
index 52dcd63..7d205f9 100644
--- a/llvm/lib/IR/Value.cpp
+++ b/llvm/lib/IR/Value.cpp
@@ -23,8 +23,10 @@
#include "llvm/IR/GetElementPtrTypeIterator.h"
#include "llvm/IR/InstrTypes.h"
#include "llvm/IR/Instructions.h"
+#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Operator.h"
+#include "llvm/IR/Statepoint.h"
#include "llvm/IR/ValueHandle.h"
#include "llvm/IR/ValueSymbolTable.h"
#include "llvm/Support/Debug.h"
@@ -570,6 +572,13 @@
return true;
}
+ // For gc.relocate, look through relocations
+ if (const IntrinsicInst *I = dyn_cast<IntrinsicInst>(V))
+ if (I->getIntrinsicID() == Intrinsic::experimental_gc_relocate) {
+ GCRelocateOperands RelocateInst(I);
+ return isDereferenceablePointer(RelocateInst.derivedPtr(), DL, Visited);
+ }
+
if (const AddrSpaceCastInst *ASC = dyn_cast<AddrSpaceCastInst>(V))
return isDereferenceablePointer(ASC->getOperand(0), DL, Visited);