diff --git a/cbackend.cpp b/cbackend.cpp
index 5262a2d3..be324934 100644
--- a/cbackend.cpp
+++ b/cbackend.cpp
@@ -4418,10 +4418,16 @@ void CWriter::visitShuffleVectorInst(llvm::ShuffleVectorInst &SVI) {
       }
       else {
         // Do an extractelement of this value from the appropriate input.
-        Out << "((";
-        printType(Out, llvm::PointerType::getUnqual(EltTy));
-        Out << ")(&" << GetValueName(Op)
-            << "))[" << SrcVal << "]";
+        if (OpElts != 1) { // all __vec16_* have overloaded operator []
+          Out << "(" << GetValueName(Op)
+              << ")[" << SrcVal << "]";
+        }
+        else { // but __vec1_* don't have it
+          Out << "((";
+          printType(Out, llvm::PointerType::getUnqual(EltTy));
+          Out << ")(&" << GetValueName(Op)
+              << "))[" << SrcVal << "]";
+        }
       }
     }
   }
diff --git a/fail_db.txt b/fail_db.txt
index 63c05d4d..a90772e0 100644
--- a/fail_db.txt
+++ b/fail_db.txt
@@ -552,11 +552,8 @@
 ./tests/gather-int8-2.ispc runfail  x86-64            knc   Linux LLVM 3.5   icpc13.1 -O2 *
 ./tests/gather-int8-4.ispc runfail  x86-64            knc   Linux LLVM 3.5   icpc15.0 -O2 *
 ./tests/gather-int8-4.ispc runfail  x86-64            knc   Linux LLVM 3.5   icpc13.1 -O2 *
-./tests/ptr-diff-3.ispc runfail  x86-64            knc   Linux LLVM 3.5   icpc15.0 -O2 *
 ./tests/ptr-diff-3.ispc runfail  x86-64            knc   Linux LLVM 3.5   icpc13.1 -O2 *
-./tests/ptr-diff-5.ispc runfail  x86-64            knc   Linux LLVM 3.5   icpc15.0 -O2 *
 ./tests/ptr-diff-5.ispc runfail  x86-64            knc   Linux LLVM 3.5   icpc13.1 -O2 *
-./tests/ptr-diff-6.ispc runfail  x86-64            knc   Linux LLVM 3.5   icpc15.0 -O2 *
 ./tests/ptr-diff-6.ispc runfail  x86-64            knc   Linux LLVM 3.5   icpc13.1 -O2 *
 ./tests/aossoa-1.ispc compfail  x86-64            knc   Linux LLVM 3.5   icpc13.1 -O2 *
 ./tests/aossoa-2.ispc compfail  x86-64            knc   Linux LLVM 3.5   icpc13.1 -O2 *
@@ -727,11 +724,8 @@
 ./tests/gather-int8-2.ispc runfail  x86-64            knc   Linux LLVM 3.6   icpc13.1 -O2 *
 ./tests/gather-int8-4.ispc runfail  x86-64            knc   Linux LLVM 3.6   icpc15.0 -O2 *
 ./tests/gather-int8-4.ispc runfail  x86-64            knc   Linux LLVM 3.6   icpc13.1 -O2 *
-./tests/ptr-diff-3.ispc runfail  x86-64            knc   Linux LLVM 3.6   icpc15.0 -O2 *
 ./tests/ptr-diff-3.ispc runfail  x86-64            knc   Linux LLVM 3.6   icpc13.1 -O2 *
-./tests/ptr-diff-5.ispc runfail  x86-64            knc   Linux LLVM 3.6   icpc15.0 -O2 *
 ./tests/ptr-diff-5.ispc runfail  x86-64            knc   Linux LLVM 3.6   icpc13.1 -O2 *
-./tests/ptr-diff-6.ispc runfail  x86-64            knc   Linux LLVM 3.6   icpc15.0 -O2 *
 ./tests/ptr-diff-6.ispc runfail  x86-64            knc   Linux LLVM 3.6   icpc13.1 -O2 *
 ./tests/aossoa-1.ispc compfail  x86-64            knc   Linux LLVM 3.6   icpc13.1 -O2 *
 ./tests/aossoa-2.ispc compfail  x86-64            knc   Linux LLVM 3.6   icpc13.1 -O2 *
@@ -896,11 +890,8 @@
 ./tests/soa-19.ispc compfail  x86-64            knc   Linux LLVM 3.6   icpc13.1 -O0 *
 ./tests/soa-22.ispc compfail  x86-64            knc   Linux LLVM 3.6   icpc13.1 -O0 *
 ./tests/struct-nested-5.ispc compfail  x86-64            knc   Linux LLVM 3.6   icpc13.1 -O0 *
-./tests/reduce-equal-10.ispc runfail  x86-64            knc   Linux LLVM 3.4   icpc15.0 -O2 *
 ./tests/reduce-equal-10.ispc runfail  x86-64            knc   Linux LLVM 3.4   icpc13.1 -O2 *
-./tests/reduce-equal-10.ispc runfail  x86-64            knc   Linux LLVM 3.5   icpc15.0 -O2 *
 ./tests/reduce-equal-10.ispc runfail  x86-64            knc   Linux LLVM 3.5   icpc13.1 -O2 *
-./tests/reduce-equal-10.ispc runfail  x86-64            knc   Linux LLVM 3.6   icpc15.0 -O2 *
 ./tests/reduce-equal-10.ispc runfail  x86-64            knc   Linux LLVM 3.6   icpc13.1 -O2 *
 ./tests/pmuls_vi64.ispc runfail  x86-64            knc   Linux LLVM 3.4   icpc13.1 -O2 *
 
@@ -909,11 +900,9 @@
 ./tests/soa-18.ispc runfail  x86-64            knc   Linux LLVM 3.4   icpc15.0 -O0 *
 ./tests/funcptr-varying-7.ispc runfail  x86-64            knc   Linux LLVM 3.5   icpc15.0 -O2 *
 ./tests/funcptr-varying-8.ispc runfail  x86-64            knc   Linux LLVM 3.5   icpc15.0 -O2 *
-./tests/pmulus_vi64.ispc runfail  x86-64            knc   Linux LLVM 3.5   icpc15.0 -O2 *
 ./tests/soa-18.ispc runfail  x86-64            knc   Linux LLVM 3.5   icpc15.0 -O0 *
 ./tests/funcptr-varying-7.ispc runfail  x86-64            knc   Linux LLVM 3.6   icpc15.0 -O2 *
 ./tests/funcptr-varying-8.ispc runfail  x86-64            knc   Linux LLVM 3.6   icpc15.0 -O2 *
-./tests/pmulus_vi64.ispc runfail  x86-64            knc   Linux LLVM 3.6   icpc15.0 -O2 *
 ./tests/soa-18.ispc runfail  x86-64            knc   Linux LLVM 3.6   icpc15.0 -O0 *
 ./tests/exclusive-scan-add-1.ispc compfail  x86-64     generic-16   Linux LLVM 3.6 clang++3.4 -O2 *
 ./tests/exclusive-scan-add-10.ispc compfail  x86-64     generic-16   Linux LLVM 3.6 clang++3.4 -O2 *
@@ -1033,11 +1022,6 @@
 ./tests/funcptr-varying-8.ispc runfail  x86-64            knc   Linux LLVM 3.7   icpc15.0 -O2 *
 ./tests/gather-int8-2.ispc runfail  x86-64            knc   Linux LLVM 3.7   icpc15.0 -O2 *
 ./tests/gather-int8-4.ispc runfail  x86-64            knc   Linux LLVM 3.7   icpc15.0 -O2 *
-./tests/pmulus_vi64.ispc runfail  x86-64            knc   Linux LLVM 3.7   icpc15.0 -O2 *
-./tests/ptr-diff-3.ispc runfail  x86-64            knc   Linux LLVM 3.7   icpc15.0 -O2 *
-./tests/ptr-diff-5.ispc runfail  x86-64            knc   Linux LLVM 3.7   icpc15.0 -O2 *
-./tests/ptr-diff-6.ispc runfail  x86-64            knc   Linux LLVM 3.7   icpc15.0 -O2 *
-./tests/reduce-equal-10.ispc runfail  x86-64            knc   Linux LLVM 3.7   icpc15.0 -O2 *
 ./tests/atomics-6.ispc compfail  x86-64            knc   Linux LLVM 3.7   icpc15.0 -O2 *
 ./tests/atomics-uniform-8.ispc compfail  x86-64            knc   Linux LLVM 3.7   icpc15.0 -O2 *
 ./tests/atomics-uniform-9.ispc compfail  x86-64            knc   Linux LLVM 3.7   icpc15.0 -O2 *