[PM] Add a new-PM-style CGSCC pass manager using the newly added

LazyCallGraph analysis framework. Wire it up all the way through the opt
driver and add some very basic testing that we can build pass pipelines
including these components. Still a lot more to do in terms of testing
that all of this works, but the basic pieces are here.

There is a *lot* of boiler plate here. It's something I'm going to
actively look at reducing, but I don't have any immediate ideas that
don't end up making the code terribly complex in order to fold away the
boilerplate. Until I figure out something to minimize the boilerplate,
almost all of this is based on the code for the existing pass managers,
copied and heavily adjusted to suit the needs of the CGSCC pass
management layer.

The actual CG management still has a bunch of FIXMEs in it. Notably, we
don't do *any* updating of the CG as it is potentially invalidated.
I wanted to get this in place to motivate the new analysis, and add
update APIs to the analysis and the pass management layers in concert to
make sure that the *right* APIs are present.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206745 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 114 insertions, 0 deletions

diff --git a/tools/opt/Passes.cpp b/tools/opt/Passes.cpp
index e4791b8ac8..a171f42691 100644
--- a/tools/opt/Passes.cpp
+++ b/tools/opt/Passes.cpp
@@ -15,6 +15,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "Passes.h"
+#include "llvm/Analysis/CGSCCPassManager.h"
 #include "llvm/Analysis/LazyCallGraph.h"
 #include "llvm/IR/IRPrintingPasses.h"
 #include "llvm/IR/PassManager.h"
@@ -31,6 +32,14 @@ struct NoOpModulePass {
   static StringRef name() { return "NoOpModulePass"; }
 };
 
+/// \brief No-op CGSCC pass which does nothing.
+struct NoOpCGSCCPass {
+  PreservedAnalyses run(LazyCallGraph::SCC *C) {
+    return PreservedAnalyses::all();
+  }
+  static StringRef name() { return "NoOpCGSCCPass"; }
+};
+
 /// \brief No-op function pass which does nothing.
 struct NoOpFunctionPass {
   PreservedAnalyses run(Function *F) { return PreservedAnalyses::all(); }
@@ -48,6 +57,15 @@ static bool isModulePassName(StringRef Name) {
   return false;
 }
 
+static bool isCGSCCPassName(StringRef Name) {
+  if (Name == "no-op-cgscc") return true;
+
+#define CGSCC_PASS(NAME, CREATE_PASS) if (Name == NAME) return true;
+#include "PassRegistry.def"
+
+  return false;
+}
+
 static bool isFunctionPassName(StringRef Name) {
   if (Name == "no-op-function") return true;
 
@@ -73,6 +91,22 @@ static bool parseModulePassName(ModulePassManager &MPM, StringRef Name) {
   return false;
 }
 
+static bool parseCGSCCPassName(CGSCCPassManager &CGPM, StringRef Name) {
+  if (Name == "no-op-cgscc") {
+    CGPM.addPass(NoOpCGSCCPass());
+    return true;
+  }
+
+#define CGSCC_PASS(NAME, CREATE_PASS)                                          \
+  if (Name == NAME) {                                                          \
+    CGPM.addPass(CREATE_PASS);                                                 \
+    return true;                                                               \
+  }
+#include "PassRegistry.def"
+
+  return false;
+}
+
 static bool parseFunctionPassName(FunctionPassManager &FPM, StringRef Name) {
   if (Name == "no-op-function") {
     FPM.addPass(NoOpFunctionPass());
@@ -126,6 +160,55 @@ static bool parseFunctionPassPipeline(FunctionPassManager &FPM,
   }
 }
 
+static bool parseCGSCCPassPipeline(CGSCCPassManager &CGPM,
+                                      StringRef &PipelineText,
+                                      bool VerifyEachPass) {
+  for (;;) {
+    // Parse nested pass managers by recursing.
+    if (PipelineText.startswith("cgscc(")) {
+      CGSCCPassManager NestedCGPM;
+
+      // Parse the inner pipeline into the nested manager.
+      PipelineText = PipelineText.substr(strlen("cgscc("));
+      if (!parseCGSCCPassPipeline(NestedCGPM, PipelineText, VerifyEachPass) ||
+          PipelineText.empty())
+        return false;
+      assert(PipelineText[0] == ')');
+      PipelineText = PipelineText.substr(1);
+
+      // Add the nested pass manager with the appropriate adaptor.
+      CGPM.addPass(std::move(NestedCGPM));
+    } else if (PipelineText.startswith("function(")) {
+      FunctionPassManager NestedFPM;
+
+      // Parse the inner pipeline inte the nested manager.
+      PipelineText = PipelineText.substr(strlen("function("));
+      if (!parseFunctionPassPipeline(NestedFPM, PipelineText, VerifyEachPass) ||
+          PipelineText.empty())
+        return false;
+      assert(PipelineText[0] == ')');
+      PipelineText = PipelineText.substr(1);
+
+      // Add the nested pass manager with the appropriate adaptor.
+      CGPM.addPass(createCGSCCToFunctionPassAdaptor(std::move(NestedFPM)));
+    } else {
+      // Otherwise try to parse a pass name.
+      size_t End = PipelineText.find_first_of(",)");
+      if (!parseCGSCCPassName(CGPM, PipelineText.substr(0, End)))
+        return false;
+      // FIXME: No verifier support for CGSCC passes!
+
+      PipelineText = PipelineText.substr(End);
+    }
+
+    if (PipelineText.empty() || PipelineText[0] == ')')
+      return true;
+
+    assert(PipelineText[0] == ',');
+    PipelineText = PipelineText.substr(1);
+  }
+}
+
 static bool parseModulePassPipeline(ModulePassManager &MPM,
                                     StringRef &PipelineText,
                                     bool VerifyEachPass) {
@@ -144,6 +227,20 @@ static bool parseModulePassPipeline(ModulePassManager &MPM,
 
       // Now add the nested manager as a module pass.
       MPM.addPass(std::move(NestedMPM));
+    } else if (PipelineText.startswith("cgscc(")) {
+      CGSCCPassManager NestedCGPM;
+
+      // Parse the inner pipeline inte the nested manager.
+      PipelineText = PipelineText.substr(strlen("cgscc("));
+      if (!parseCGSCCPassPipeline(NestedCGPM, PipelineText, VerifyEachPass) ||
+          PipelineText.empty())
+        return false;
+      assert(PipelineText[0] == ')');
+      PipelineText = PipelineText.substr(1);
+
+      // Add the nested pass manager with the appropriate adaptor.
+      MPM.addPass(
+          createModuleToPostOrderCGSCCPassAdaptor(std::move(NestedCGPM)));
     } else if (PipelineText.startswith("function(")) {
       FunctionPassManager NestedFPM;
 
@@ -185,6 +282,14 @@ bool llvm::parsePassPipeline(ModulePassManager &MPM, StringRef PipelineText,
   if (PipelineText.startswith("module("))
     return parseModulePassPipeline(MPM, PipelineText, VerifyEachPass) &&
            PipelineText.empty();
+  if (PipelineText.startswith("cgscc(")) {
+    CGSCCPassManager CGPM;
+    if (!parseCGSCCPassPipeline(CGPM, PipelineText, VerifyEachPass) ||
+        !PipelineText.empty())
+      return false;
+    MPM.addPass(createModuleToPostOrderCGSCCPassAdaptor(std::move(CGPM)));
+    return true;
+  }
   if (PipelineText.startswith("function(")) {
     FunctionPassManager FPM;
     if (!parseFunctionPassPipeline(FPM, PipelineText, VerifyEachPass) ||
@@ -201,6 +306,15 @@ bool llvm::parsePassPipeline(ModulePassManager &MPM, StringRef PipelineText,
     return parseModulePassPipeline(MPM, PipelineText, VerifyEachPass) &&
            PipelineText.empty();
 
+  if (isCGSCCPassName(FirstName)) {
+    CGSCCPassManager CGPM;
+    if (!parseCGSCCPassPipeline(CGPM, PipelineText, VerifyEachPass) ||
+        !PipelineText.empty())
+      return false;
+    MPM.addPass(createModuleToPostOrderCGSCCPassAdaptor(std::move(CGPM)));
+    return true;
+  }
+
   if (isFunctionPassName(FirstName)) {
     FunctionPassManager FPM;
     if (!parseFunctionPassPipeline(FPM, PipelineText, VerifyEachPass) ||