Add an insertPass API to TargetPassConfig. <rdar://problem/11498613>

Besides adding the new insertPass function, this patch uses it to
enhance the existing -print-machineinstrs so that the MachineInstrs
after a specific pass can be printed.

Patch by Bin Zeng!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157655 91177308-0d34-0410-b5e6-96231b3b80d8

7 files changed, 70 insertions, 6 deletions

diff --git a/include/llvm/CodeGen/Passes.h b/include/llvm/CodeGen/Passes.h
index e76fe99257..567a9f7d7b 100644
--- a/include/llvm/CodeGen/Passes.h
+++ b/include/llvm/CodeGen/Passes.h
@@ -101,6 +101,9 @@ public:
   /// point where StadardID is expected, add TargetID in its place.
   void substitutePass(char &StandardID, char &TargetID);
 
+  /// Insert InsertedPassID pass after TargetPassID pass.
+  void insertPass(const char &TargetPassID, const char &InsertedPassID);
+
   /// Allow the target to enable a specific standard pass by default.
   void enablePass(char &ID) { substitutePass(ID, ID); }
 
@@ -342,6 +345,9 @@ namespace llvm {
   /// branches.
   extern char &BranchFolderPassID;
 
+  /// MachineFunctionPrinterPass - This pass prints out MachineInstr's.
+  extern char &MachineFunctionPrinterPassID;
+
   /// TailDuplicate - Duplicate blocks with unconditional branches
   /// into tails of their predecessors.
   extern char &TailDuplicateID;
diff --git a/include/llvm/InitializePasses.h b/include/llvm/InitializePasses.h
index df696b1814..3b9b59fe9e 100644
--- a/include/llvm/InitializePasses.h
+++ b/include/llvm/InitializePasses.h
@@ -252,6 +252,7 @@ void initializeInstSimplifierPass(PassRegistry&);
 void initializeUnpackMachineBundlesPass(PassRegistry&);
 void initializeFinalizeMachineBundlesPass(PassRegistry&);
 void initializeBBVectorizePass(PassRegistry&);
+void initializeMachineFunctionPrinterPassPass(PassRegistry&);
 }
 
 #endif
diff --git a/lib/CodeGen/CodeGen.cpp b/lib/CodeGen/CodeGen.cpp
index a81bb5cc55..65487136e8 100644
--- a/lib/CodeGen/CodeGen.cpp
+++ b/lib/CodeGen/CodeGen.cpp
@@ -66,6 +66,7 @@ void llvm::initializeCodeGen(PassRegistry &Registry) {
   initializeUnreachableMachineBlockElimPass(Registry);
   initializeVirtRegMapPass(Registry);
   initializeLowerIntrinsicsPass(Registry);
+  initializeMachineFunctionPrinterPassPass(Registry);
 }
 
 void LLVMInitializeCodeGen(LLVMPassRegistryRef R) {
diff --git a/lib/CodeGen/MachineFunctionPrinterPass.cpp b/lib/CodeGen/MachineFunctionPrinterPass.cpp
index 2aaa798a02..dbda93e4fd 100644
--- a/lib/CodeGen/MachineFunctionPrinterPass.cpp
+++ b/lib/CodeGen/MachineFunctionPrinterPass.cpp
@@ -15,6 +15,7 @@
 #include "llvm/CodeGen/MachineFunctionPass.h"
 #include "llvm/CodeGen/MachineFunction.h"
 #include "llvm/Support/raw_ostream.h"
+#include "llvm/Support/Debug.h"
 
 using namespace llvm;
 
@@ -28,6 +29,7 @@ struct MachineFunctionPrinterPass : public MachineFunctionPass {
   raw_ostream &OS;
   const std::string Banner;
 
+  MachineFunctionPrinterPass() : MachineFunctionPass(ID), OS(dbgs()) { }
   MachineFunctionPrinterPass(raw_ostream &os, const std::string &banner) 
       : MachineFunctionPass(ID), OS(os), Banner(banner) {}
 
@@ -48,6 +50,10 @@ struct MachineFunctionPrinterPass : public MachineFunctionPass {
 char MachineFunctionPrinterPass::ID = 0;
 }
 
+char &MachineFunctionPrinterPassID = MachineFunctionPrinterPass::ID;
+INITIALIZE_PASS(MachineFunctionPrinterPass, "print-machineinstrs",
+                "Machine Function Printer", false, false)
+
 namespace llvm {
 /// Returns a newly-created MachineFunction Printer pass. The
 /// default banner is empty.
diff --git a/lib/CodeGen/Passes.cpp b/lib/CodeGen/Passes.cpp
index 490547bbb8..feac061ffd 100644
--- a/lib/CodeGen/Passes.cpp
+++ b/lib/CodeGen/Passes.cpp
@@ -80,6 +80,10 @@ static cl::opt<bool> PrintGCInfo("print-gc", cl::Hidden,
 static cl::opt<bool> VerifyMachineCode("verify-machineinstrs", cl::Hidden,
     cl::desc("Verify generated machine code"),
     cl::init(getenv("LLVM_VERIFY_MACHINEINSTRS")!=NULL));
+static cl::opt<std::string>
+PrintMachineInstrs("print-machineinstrs", cl::ValueOptional,
+                   cl::desc("Print machine instrs"),
+                   cl::value_desc("pass-name"), cl::init("option-unspecified"));
 
 /// Allow standard passes to be disabled by command line options. This supports
 /// simple binary flags that either suppress the pass or do nothing.
@@ -196,6 +200,10 @@ public:
   // default by substituting NoPass, and the user may still enable that standard
   // pass with an explicit command line option.
   DenseMap<AnalysisID,AnalysisID> TargetPasses;
+
+  /// Store the pairs of <AnalysisID, AnalysisID> of which the second pass
+  /// is inserted after each instance of the first one.
+  SmallVector<std::pair<AnalysisID, AnalysisID>, 4> InsertedPasses;
 };
 } // namespace llvm
 
@@ -225,6 +233,14 @@ TargetPassConfig::TargetPassConfig(TargetMachine *tm, PassManagerBase &pm)
   substitutePass(MachineSchedulerID, NoPassID);
 }
 
+/// Insert InsertedPassID pass after TargetPassID.
+void TargetPassConfig::insertPass(const char &TargetPassID,
+                                  const char &InsertedPassID) {
+  assert(&TargetPassID != &InsertedPassID && "Insert a pass after itself!");
+  std::pair<AnalysisID, AnalysisID> P(&TargetPassID, &InsertedPassID);
+  Impl->InsertedPasses.push_back(P);
+}
+
 /// createPassConfig - Create a pass configuration object to be used by
 /// addPassToEmitX methods for generating a pipeline of CodeGen passes.
 ///
@@ -270,6 +286,17 @@ AnalysisID TargetPassConfig::addPass(char &ID) {
   if (!P)
     llvm_unreachable("Pass ID not registered");
   PM->add(P);
+  // Add the passes after the pass P if there is any.
+  for (SmallVector<std::pair<AnalysisID, AnalysisID>, 4>::iterator
+         I = Impl->InsertedPasses.begin(), E = Impl->InsertedPasses.end();
+       I != E; ++I) {
+    if ((*I).first == &ID) {
+      assert((*I).second && "Illegal Pass ID!");
+      Pass *NP = Pass::createPass((*I).second);
+      assert(NP && "Pass ID not registered");
+      PM->add(NP);
+    }
+  }
   return FinalID;
 }
 
@@ -352,6 +379,21 @@ void TargetPassConfig::addMachinePasses() {
   // Print the instruction selected machine code...
   printAndVerify("After Instruction Selection");
 
+  // Insert a machine instr printer pass after the specified pass.
+  // If -print-machineinstrs specified, print machineinstrs after all passes.
+  if (StringRef(PrintMachineInstrs.getValue()).equals(""))
+    TM->Options.PrintMachineCode = true;
+  else if (!StringRef(PrintMachineInstrs.getValue())
+           .equals("option-unspecified")) {
+    const PassRegistry *PR = PassRegistry::getPassRegistry();
+    const PassInfo *TPI = PR->getPassInfo(PrintMachineInstrs.getValue());
+    const PassInfo *IPI = PR->getPassInfo(StringRef("print-machineinstrs"));
+    assert (TPI && IPI && "Pass ID not registered!");
+    const char *TID = (char *)(TPI->getTypeInfo());
+    const char *IID = (char *)(IPI->getTypeInfo());
+    insertPass(*TID, *IID);
+  }
+
   // Expand pseudo-instructions emitted by ISel.
   addPass(ExpandISelPseudosID);
 
diff --git a/test/CodeGen/Generic/print-machineinstrs.ll b/test/CodeGen/Generic/print-machineinstrs.ll
new file mode 100644
index 0000000000..75b4cd14ff
--- /dev/null
+++ b/test/CodeGen/Generic/print-machineinstrs.ll
@@ -0,0 +1,14 @@
+; RUN: llc < %s -O3 -debug-pass=Structure -print-machineinstrs=branch-folder -o /dev/null |& FileCheck %s
+; RUN: llc < %s -O3 -debug-pass=Structure -print-machineinstrs -o /dev/null |& FileCheck %s
+; RUN: llc < %s -O3 -debug-pass=Structure -print-machineinstrs= -o /dev/null |& FileCheck %s
+
+define i64 @foo(i64 %a, i64 %b) nounwind {
+; CHECK: -branch-folder -print-machineinstrs
+; CHECK: Control Flow Optimizer
+; CHECK-NEXT: MachineFunction Printer
+; CHECK: Machine code for function foo:
+  %c = add i64 %a, %b
+  %d = trunc i64 %c to i32
+  %e = zext i32 %d to i64
+  ret i64 %e
+}
diff --git a/tools/llc/llc.cpp b/tools/llc/llc.cpp
index 9f4ab70ba7..35275d7918 100644
--- a/tools/llc/llc.cpp
+++ b/tools/llc/llc.cpp
@@ -146,11 +146,6 @@ EnableFPMAD("enable-fp-mad",
   cl::init(false));
 
 static cl::opt<bool>
-PrintCode("print-machineinstrs",
-  cl::desc("Print generated machine code"),
-  cl::init(false));
-
-static cl::opt<bool>
 DisableFPElim("disable-fp-elim",
   cl::desc("Disable frame pointer elimination optimization"),
   cl::init(false));
@@ -403,7 +398,6 @@ int main(int argc, char **argv) {
 
   TargetOptions Options;
   Options.LessPreciseFPMADOption = EnableFPMAD;
-  Options.PrintMachineCode = PrintCode;
   Options.NoFramePointerElim = DisableFPElim;
   Options.NoFramePointerElimNonLeaf = DisableFPElimNonLeaf;
   Options.NoExcessFPPrecision = DisableExcessPrecision;