Add PNaClSjLjEH pass to implement C++ exception handling using setjmp()+longjmp()

There are two parts to this:

 * PNaClSjLjEH.cpp expands out the "invoke", "landingpad" and "resume"
   instructions, modifying the control flow to use setjmp().

 * ExceptionInfoWriter.cpp lowers landingpads' clause lists to data
   that PNaCl's C++ runtime library will interpret.  This part will be
   reused when we drop the SjLj part and create a stable ABI for
   zero-cost EH.

This pass isn't enabled in PNaClABISimplify yet: I'll do that in a
separate change.

BUG=https://code.google.com/p/nativeclient/issues/detail?id=3696
TEST=*.ll tests (also tested end-to-end: plumbing for this will follow later)

Review URL: https://codereview.chromium.org/24777002

2 files changed, 2 insertions, 0 deletions

diff --git a/include/llvm/InitializePasses.h b/include/llvm/InitializePasses.h
index fd59d14b54..f471c55cd9 100644
--- a/include/llvm/InitializePasses.h
+++ b/include/llvm/InitializePasses.h
@@ -293,6 +293,7 @@ void initializeInsertDivideCheckPass(PassRegistry&);
 void initializeNaClCcRewritePass(PassRegistry&);
 void initializePNaClABIVerifyFunctionsPass(PassRegistry&);
 void initializePNaClABIVerifyModulePass(PassRegistry&);
+void initializePNaClSjLjEHPass(PassRegistry&);
 void initializePromoteI1OpsPass(PassRegistry&);
 void initializePromoteIntegersPass(PassRegistry&);
 void initializeRemoveAsmMemoryPass(PassRegistry&);
diff --git a/include/llvm/Transforms/NaCl.h b/include/llvm/Transforms/NaCl.h
index e1be3cf85b..ba85c592f5 100644
--- a/include/llvm/Transforms/NaCl.h
+++ b/include/llvm/Transforms/NaCl.h
@@ -41,6 +41,7 @@ ModulePass *createExpandTlsPass();
 ModulePass *createExpandVarArgsPass();
 ModulePass *createFlattenGlobalsPass();
 ModulePass *createGlobalCleanupPass();
+ModulePass *createPNaClSjLjEHPass();
 ModulePass *createReplacePtrsWithIntsPass();
 ModulePass *createResolveAliasesPass();
 ModulePass *createRewriteAtomicsPass();