SROA: Avoid struct and array types early to avoid creating an overly large integer...

Fixes PR14465.

Differential Revision: http://llvm-reviews.chandlerc.com/D148

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169084 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Transforms/Scalar/SROA.cpp b/lib/Transforms/Scalar/SROA.cpp
index e850e618198546e90160daf248e4d67af67b3196..68d5d3f01a05f15ae394bd89df0102e795da36d6 100644 (file)
--- a/lib/Transforms/Scalar/SROA.cpp
+++ b/lib/Transforms/Scalar/SROA.cpp
@@ -2164,6 +2164,9 @@ static bool isIntegerWideningViable(const DataLayout &TD,
                                     AllocaPartitioning::const_use_iterator I,
                                     AllocaPartitioning::const_use_iterator E) {
   uint64_t SizeInBits = TD.getTypeSizeInBits(AllocaTy);
+  // Don't create integer types larger than the maximum bitwidth.
+  if (SizeInBits > IntegerType::MAX_INT_BITS)
+    return false;
 
   // Don't try to handle allocas with bit-padding.
   if (SizeInBits != TD.getTypeStoreSizeInBits(AllocaTy))

diff --git a/test/Transforms/SROA/basictest.ll b/test/Transforms/SROA/basictest.ll
index b363eefb3f9d9ca1e320b40d686009e2329e951d..a291c39b33f21d3bf5c4d104acadfe51cddf349e 100644 (file)
--- a/test/Transforms/SROA/basictest.ll
+++ b/test/Transforms/SROA/basictest.ll
@@ -1134,3 +1134,16 @@ entry:
   ret void
 ; CHECK: ret
 }
+
+define void @PR14465() {
+; Ensure that we don't crash when analyzing a alloca larger than the maximum
+; integer type width (MAX_INT_BITS) supported by llvm (1048576*32 > (1<<23)-1).
+; CHECK: @PR14465
+
+  %stack = alloca [1048576 x i32], align 16
+; CHECK: alloca [1048576 x i32]
+  %cast = bitcast [1048576 x i32]* %stack to i8*
+  call void @llvm.memset.p0i8.i64(i8* %cast, i8 -2, i64 4194304, i32 16, i1 false)
+  ret void
+; CHECK: ret
+}