[llvm] r365864 - Return Undef from isBytewiseValue for empty arrays or structs

[Vitaly Buka via llvm-commits]

Author: vitalybuka
Date: Thu Jul 11 19:23:07 2019
New Revision: 365864

URL: http://llvm.org/viewvc/llvm-project?rev=365864&view=rev
Log:
Return Undef from isBytewiseValue for empty arrays or structs

Reviewers: pcc, eugenis

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D64052

Modified:
    llvm/trunk/lib/Analysis/ValueTracking.cpp
    llvm/trunk/unittests/Analysis/ValueTrackingTest.cpp

Modified: llvm/trunk/lib/Analysis/ValueTracking.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/ValueTracking.cpp?rev=365864&r1=365863&r2=365864&view=diff
==============================================================================
--- llvm/trunk/lib/Analysis/ValueTracking.cpp (original)
+++ llvm/trunk/lib/Analysis/ValueTracking.cpp Thu Jul 11 19:23:07 2019
@@ -3178,6 +3178,10 @@ Value *llvm::isBytewiseValue(Value *V, c
   if (isa<UndefValue>(V))
     return UndefInt8;
 
+  const uint64_t Size = DL.getTypeStoreSize(V->getType());
+  if (!Size)
+    return UndefInt8;
+
   Constant *C = dyn_cast<Constant>(V);
   if (!C) {
     // Conceptually, we could handle things like:

Modified: llvm/trunk/unittests/Analysis/ValueTrackingTest.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/unittests/Analysis/ValueTrackingTest.cpp?rev=365864&r1=365863&r2=365864&view=diff
==============================================================================
--- llvm/trunk/unittests/Analysis/ValueTrackingTest.cpp (original)
+++ llvm/trunk/unittests/Analysis/ValueTrackingTest.cpp Thu Jul 11 19:23:07 2019
@@ -810,7 +810,7 @@ const std::pair<const char *, const char
         "i16* inttoptr (i96 -1 to i16*)",
     },
     {
-        "i8 0",
+        "i8 undef",
         "[0 x i8] zeroinitializer",
     },
     {
@@ -818,7 +818,7 @@ const std::pair<const char *, const char
         "[0 x i8] undef",
     },
     {
-        "i8 0",
+        "i8 undef",
         "[5 x [0 x i8]] zeroinitializer",
     },
     {
@@ -900,7 +900,7 @@ const std::pair<const char *, const char
         "[2 x i16] [i16 -21836, i16 -21846]]",
     },
     {
-        "i8 0",
+        "i8 undef",
         "{ } zeroinitializer",
     },
     {
@@ -908,7 +908,7 @@ const std::pair<const char *, const char
         "{ } undef",
     },
     {
-        "i8 0",
+        "i8 undef",
         "{ {}, {} } zeroinitializer",
     },
     {