Teach MemoryBuiltins and InstructionSimplify that operator new never returns NULL.
This is safe per C++11 18.6.1.1p3: [operator new returns] a non-null pointer to
suitably aligned storage (3.7.4), or else throw a bad_alloc exception. This
requirement is binding on a replacement version of this function.
Brings us a tiny bit closer to eliminating more vector push_backs.
llvm-svn: 191310
diff --git a/llvm/test/Transforms/InstSimplify/call.ll b/llvm/test/Transforms/InstSimplify/call.ll
index 3e1621c..aa3b086 100644
--- a/llvm/test/Transforms/InstSimplify/call.ll
+++ b/llvm/test/Transforms/InstSimplify/call.ll
@@ -101,3 +101,23 @@
ret float %r4
}
+
+define i8* @operator_new() {
+entry:
+ %call = tail call noalias i8* @_Znwm(i64 8)
+ %cmp = icmp eq i8* %call, null
+ br i1 %cmp, label %cast.end, label %cast.notnull
+
+cast.notnull: ; preds = %entry
+ %add.ptr = getelementptr inbounds i8* %call, i64 4
+ br label %cast.end
+
+cast.end: ; preds = %cast.notnull, %entry
+ %cast.result = phi i8* [ %add.ptr, %cast.notnull ], [ null, %entry ]
+ ret i8* %cast.result
+
+; CHECK-LABEL: @operator_new
+; CHECK: br i1 false, label %cast.end, label %cast.notnull
+}
+
+declare noalias i8* @_Znwm(i64)