[llvm-branch-commits] [llvm-branch] r229588 - Merging r229352:

[Hans Wennborg]

Author: hans
Date: Tue Feb 17 17:40:20 2015
New Revision: 229588

URL: http://llvm.org/viewvc/llvm-project?rev=229588&view=rev
Log:
Merging r229352:
------------------------------------------------------------------------
r229352 | majnemer | 2015-02-15 20:02:09 -0800 (Sun, 15 Feb 2015) | 8 lines

IR: Properly return nullptr when getAggregateElement is out-of-bounds

We didn't properly handle the out-of-bounds case for
ConstantAggregateZero and UndefValue.  This would manifest as a crash
when the constant folder was asked to fold a load of a constant global
whose struct type has no operands.

This fixes PR22595.
------------------------------------------------------------------------

Added:
    llvm/branches/release_36/test/Transforms/InstSimplify/load.ll
      - copied unchanged from r229352, llvm/trunk/test/Transforms/InstSimplify/load.ll
Modified:
    llvm/branches/release_36/   (props changed)
    llvm/branches/release_36/include/llvm/IR/Constants.h
    llvm/branches/release_36/lib/IR/Constants.cpp

Propchange: llvm/branches/release_36/
------------------------------------------------------------------------------
--- svn:mergeinfo (original)
+++ svn:mergeinfo Tue Feb 17 17:40:20 2015
@@ -1,3 +1,3 @@
 /llvm/branches/Apple/Pertwee:110850,110961
 /llvm/branches/type-system-rewrite:133420-134817
-/llvm/trunk:155241,226023,226029,226044,226046,226048,226058,226075,226170-226171,226182,226473,226588,226616,226664,226708,226711,226755,226791,226808-226809,227005,227085,227250,227260-227261,227290,227294,227299,227319,227339,227491,227584,227603,227628,227670,227809,227815,227903,227934,227972,227983,228049,228129,228168,228331,228411,228444,228490,228500,228507,228518,228525,228565,228656,228760-228761,228793,228842,228899,228957,228969,228979,229029,229343,229351,229421,229495,229529
+/llvm/trunk:155241,226023,226029,226044,226046,226048,226058,226075,226170-226171,226182,226473,226588,226616,226664,226708,226711,226755,226791,226808-226809,227005,227085,227250,227260-227261,227290,227294,227299,227319,227339,227491,227584,227603,227628,227670,227809,227815,227903,227934,227972,227983,228049,228129,228168,228331,228411,228444,228490,228500,228507,228518,228525,228565,228656,228760-228761,228793,228842,228899,228957,228969,228979,229029,229343,229351-229352,229421,229495,229529

Modified: llvm/branches/release_36/include/llvm/IR/Constants.h
URL: http://llvm.org/viewvc/llvm-project/llvm/branches/release_36/include/llvm/IR/Constants.h?rev=229588&r1=229587&r2=229588&view=diff
==============================================================================
--- llvm/branches/release_36/include/llvm/IR/Constants.h (original)
+++ llvm/branches/release_36/include/llvm/IR/Constants.h Tue Feb 17 17:40:20 2015
@@ -325,6 +325,9 @@ public:
   /// index.
   Constant *getElementValue(unsigned Idx) const;
 
+  /// \brief Return the number of elements in the array, vector, or struct.
+  unsigned getNumElements() const;
+
   /// Methods for support type inquiry through isa, cast, and dyn_cast:
   ///
   static bool classof(const Value *V) {
@@ -1196,6 +1199,9 @@ public:
   /// index.
   UndefValue *getElementValue(unsigned Idx) const;
 
+  /// \brief Return the number of elements in the array, vector, or struct.
+  unsigned getNumElements() const;
+
   void destroyConstant() override;
 
   /// Methods for support type inquiry through isa, cast, and dyn_cast:

Modified: llvm/branches/release_36/lib/IR/Constants.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/branches/release_36/lib/IR/Constants.cpp?rev=229588&r1=229587&r2=229588&view=diff
==============================================================================
--- llvm/branches/release_36/lib/IR/Constants.cpp (original)
+++ llvm/branches/release_36/lib/IR/Constants.cpp Tue Feb 17 17:40:20 2015
@@ -257,11 +257,11 @@ Constant *Constant::getAggregateElement(
   if (const ConstantVector *CV = dyn_cast<ConstantVector>(this))
     return Elt < CV->getNumOperands() ? CV->getOperand(Elt) : nullptr;
 
-  if (const ConstantAggregateZero *CAZ =dyn_cast<ConstantAggregateZero>(this))
-    return CAZ->getElementValue(Elt);
+  if (const ConstantAggregateZero *CAZ = dyn_cast<ConstantAggregateZero>(this))
+    return Elt < CAZ->getNumElements() ? CAZ->getElementValue(Elt) : nullptr;
 
   if (const UndefValue *UV = dyn_cast<UndefValue>(this))
-    return UV->getElementValue(Elt);
+    return Elt < UV->getNumElements() ? UV->getElementValue(Elt) : nullptr;
 
   if (const ConstantDataSequential *CDS =dyn_cast<ConstantDataSequential>(this))
     return Elt < CDS->getNumElements() ? CDS->getElementAsConstant(Elt)
@@ -764,6 +764,14 @@ Constant *ConstantAggregateZero::getElem
   return getStructElement(Idx);
 }
 
+unsigned ConstantAggregateZero::getNumElements() const {
+  const Type *Ty = getType();
+  if (const auto *AT = dyn_cast<ArrayType>(Ty))
+    return AT->getNumElements();
+  if (const auto *VT = dyn_cast<VectorType>(Ty))
+    return VT->getNumElements();
+  return Ty->getStructNumElements();
+}
 
 //===----------------------------------------------------------------------===//
 //                         UndefValue Implementation
@@ -797,7 +805,14 @@ UndefValue *UndefValue::getElementValue(
   return getStructElement(Idx);
 }
 
-
+unsigned UndefValue::getNumElements() const {
+  const Type *Ty = getType();
+  if (const auto *AT = dyn_cast<ArrayType>(Ty))
+    return AT->getNumElements();
+  if (const auto *VT = dyn_cast<VectorType>(Ty))
+    return VT->getNumElements();
+  return Ty->getStructNumElements();
+}
 
 //===----------------------------------------------------------------------===//
 //                            ConstantXXX Classes