Extend TargetPassConfig to allow running only a subset of the normal passes.

This is still a work in progress but I believe it is currently good enough
to fix PR13122 "Need unit test driver for codegen IR passes".  For example,
you can run llc with -stop-after=loop-reduce to have it dump out the IR after
running LSR.  Serializing machine-level IR is not yet supported but we have
some patches in progress for that.

The plan is to serialize the IR to a YAML file, containing separate sections
for the LLVM IR, machine-level IR, and whatever other info is needed.  Chad
suggested that we stash the stop-after pass in the YAML file and use that
instead of the start-after option to figure out where to restart the
compilation.  I think that's a great idea, but since it's not implemented yet
I put the -start-after option into this patch for testing purposes.

llvm-svn: 159570

1 files changed, 3 insertions, 1 deletions

diff --git a/llvm/lib/Target/CppBackend/CPPBackend.cpp b/llvm/lib/Target/CppBackend/CPPBackend.cpp
index 0ea2a299dd8..c8e757becc7 100644
--- a/llvm/lib/Target/CppBackend/CPPBackend.cpp
+++ b/llvm/lib/Target/CppBackend/CPPBackend.cpp
@@ -2101,7 +2101,9 @@ char CppWriter::ID = 0;
 bool CPPTargetMachine::addPassesToEmitFile(PassManagerBase &PM,
                                            formatted_raw_ostream &o,
                                            CodeGenFileType FileType,
-                                           bool DisableVerify) {
+                                           bool DisableVerify,
+                                           AnalysisID StartAfter,
+                                           AnalysisID StopAfter) {
   if (FileType != TargetMachine::CGFT_AssemblyFile) return true;
   PM.add(new CppWriter(o));
   return false;