Add the new @llvm.nacl.atomic.fence.all intrinsic

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 12 matching lines @@
 
 void llvm::PNaClABISimplifyAddPreOptPasses(PassManager &PM) {
   // Internalize all symbols in the module except _start, which is the only
   // symbol a stable PNaCl pexe is allowed to export.
   const char *SymbolsToPreserve[] = { "_start" };
   PM.add(createInternalizePass(SymbolsToPreserve));
 
   // LowerExpect converts Intrinsic::expect into branch weights,
   // which can then be removed after BlockPlacement.
   PM.add(createLowerExpectIntrinsicPass());
-  // Rewrite unsupported intrinsics and inline assembly directives to
-  // simpler and portable constructs.
+  // Rewrite unsupported intrinsics to simpler and portable constructs.
   PM.add(createRewriteLLVMIntrinsicsPass());
-  PM.add(createRewriteAsmDirectivesPass());
   // LowerInvoke prevents use of C++ exception handling, which is not
   // yet supported in the PNaCl ABI.
   PM.add(createLowerInvokePass());
   // Remove landingpad blocks made unreachable by LowerInvoke.
   PM.add(createCFGSimplificationPass());
 
   // Expand out some uses of struct types.
   PM.add(createExpandArithWithOverflowPass());
   // ExpandStructRegs must be run after ExpandArithWithOverflow to
   // expand out the insertvalue instructions that
@@ skipping 44 matching lines @@
   // because they might reintroduce ConstantExprs.
   PM.add(createExpandConstantExprPass());
   // PromoteIntegersPass does not handle constexprs and creates GEPs,
   // so it goes between those passes.
   PM.add(createPromoteIntegersPass());
   // ExpandGetElementPtr must follow ExpandConstantExpr to expand the
   // getelementptr instructions it creates.
   PM.add(createExpandGetElementPtrPass());
   // Rewrite atomic and volatile instructions with intrinsic calls.
   PM.add(createRewriteAtomicsPass());
+  // Remove ``asm("":::"memory")``. This must occur after rewriting
+  // atomics: a ``fence seq_cst`` surrounded by ``asm("":::"memory")``
+  // has special meaning and is translated differently.
+  PM.add(createRemoveAsmMemoryPass());
   // ReplacePtrsWithInts assumes that getelementptr instructions and
   // ConstantExprs have already been expanded out.
   PM.add(createReplacePtrsWithIntsPass());
 
   // We place StripAttributes after optimization passes because many
   // analyses add attributes to reflect their results.
   // StripAttributes must come after ExpandByVal and
   // ExpandSmallArguments.
   PM.add(createStripAttributesPass());
 
   // 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());
 }