PNaCl: Add support for GCC/LLVM vector extensions

lib/Transforms/NaCl/PNaClABISimplify.cpp

 //===-- PNaClABISimplify.cpp - Lists PNaCl ABI simplification passes ------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This file implements the meta-passes "-pnacl-abi-simplify-preopt"
@@ skipping 74 matching lines @@
   PM.add(createExpandByValPass());
 
   // We place ExpandSmallArguments after optimization passes because
   // some optimizations undo its changes.  Note that
   // ExpandSmallArguments requires that ExpandVarArgs has already been
   // run.
   PM.add(createExpandSmallArgumentsPass());
 
   PM.add(createPromoteI1OpsPass());
 
+  // Vector simplifications.
+  // TODO(jfb) Remove duplicate constant vector values using
+  //           ConstantMerge after the GlobalizeConstantVectors pass?
+  PM.add(createGlobalizeConstantVectorsPass());
+  // The following pass inserts GEPs, it must precede
+  // ExpandGetElementPtr. It also creates vector loads and stores, the
+  // subsequent pass cleans them up to fix their alignment.
+  PM.add(createConstantInsertExtractElementIndexPass());
+  PM.add(createFixVectorLoadStoreAlignmentPass());
+
   // Optimization passes and ExpandByVal introduce
   // memset/memcpy/memmove intrinsics with a 64-bit size argument.
   // This pass converts those arguments to 32-bit.
   PM.add(createCanonicalizeMemIntrinsicsPass());
 
   // We place StripMetadata after optimization passes because
   // optimizations depend on the metadata.
   PM.add(createStripMetadataPass());
 
   // FlattenGlobals introduces ConstantExpr bitcasts of globals which
@@ skipping 28 matching lines @@
   // Strip dead prototytes to appease the intrinsic ABI checks.
   // ExpandVarArgs leaves around vararg intrinsics, and
   // ReplacePtrsWithInts leaves the lifetime.start/end intrinsics.
   PM.add(createStripDeadPrototypesPass());
 
   // Eliminate simple dead code that the post-opt passes could have
   // created.
   PM.add(createDeadInstEliminationPass());
   PM.add(createDeadCodeEliminationPass());
 }